Vesicle Enlargement Research Articles

Involvement of mTOR pathway in neurodegeneration in NSF-related developmental and epileptic encephalopathy.

Membrane fusion is mediated by soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins. During neurotransmitter exocytosis, SNARE proteins on a synaptic vesicle and the target membrane form a complex, resulting in neurotransmitter release. N-ethylmaleimide-sensitive factor (NSF), a homohexameric ATPase, disassembles the complex, allowing individual SNARE proteins to be recycled. Recently, the association between pathogenic NSF variants and developmental and epileptic encephalopathy (DEE) was reported; however, the molecular pathomechanism of NSF-related DEE remains unclear. Here, three patients with de novo heterozygous NSF variants were presented, of which two were associated with DEE and one with a very mild phenotype. One of the DEE patients also had hypocalcemia from parathyroid hormone deficiency and neuromuscular junction impairment. Using PC12 cells, a neurosecretion model, we show that NSF with DEE-associated variants impaired the recycling of vesicular membrane proteins and vesicle enlargement in response to exocytotic stimulation. In addition, DEE-associated variants caused neurodegenerative change and defective autophagy through overactivation of the mammalian/mechanistic target of rapamycin (mTOR) pathway. Treatment with rapamycin, an mTOR inhibitor or overexpression of wild-type NSF ameliorated these phenotypes. Furthermore, neurons differentiated from patient-derived induced pluripotent stem cells showed neurite degeneration, which was also alleviated by rapamycin treatment or gene correction using genome editing. Protein structure analysis of NSF revealed that DEE-associated variants might disrupt the transmission of the conformational change of NSF monomers and consequently halt the rotation of ATP hydrolysis, indicating a dominant negative mechanism. In conclusion, this study elucidates the pathomechanism underlying NSF-related DEE and identifies a potential therapeutic approach.

A Recurrent Gain-of-Function Mutation in CLCN6, Encoding the ClC-6 Cl−/H+-Exchanger, Causes Early-Onset Neurodegeneration

Dysfunction of the endolysosomal system is often associated with neurodegenerative disease because postmitotic neurons are particularly reliant on the elimination of intracellular aggregates. Adequate function of endosomes and lysosomes requires finely tuned luminal ion homeostasis and transmembrane ion fluxes. Endolysosomal CLC Cl-/H+ exchangers function as electric shunts for proton pumping and in luminal Cl- accumulation. We now report three unrelated children with severe neurodegenerative disease, who carry the same de novo c.1658A>G (p.Tyr553Cys) mutation in CLCN6, encoding the late endosomal Cl-/H+-exchanger ClC-6. Whereas Clcn6-/- mice have only mild neuronal lysosomal storage abnormalities, the affected individuals displayed severe developmental delay with pronounced generalized hypotonia, respiratory insufficiency, and variable neurodegeneration and diffusion restriction in cerebral peduncles, midbrain, and/or brainstem in MRI scans. The p.Tyr553Cys amino acid substitution strongly slowed ClC-6 gating and increased current amplitudes, particularly at the acidic pH of late endosomes. Transfection of ClC-6Tyr553Cys, but not ClC-6WT, generated giant LAMP1-positive vacuoles that were poorly acidified. Their generation strictly required ClC-6 ion transport, as shown by transport-deficient double mutants, and depended on Cl-/H+ exchange, as revealed by combination with the uncoupling p.Glu200Ala substitution. Transfection of either ClC-6Tyr553Cys/Glu200Ala or ClC-6Glu200Ala generated slightly enlarged vesicles, suggesting that p.Glu200Ala, previously associated with infantile spasms and microcephaly, is also pathogenic. Bafilomycin treatment abrogated vacuole generation, indicating that H+-driven Cl- accumulation osmotically drives vesicle enlargement. Our work establishes mutations in CLCN6 associated with neurological diseases, whose spectrum of clinical features depends on the differential impact of the allele on ClC-6 function.

A Prospective Study to Evaluate Sexual Dysfunction and Enlargement of Seminal Vesicles in Sexually Active Men Treated for Benign Prostatic Hyperplasia by Alpha-blockers

To evaluate sexual dysfunction and enlargement of seminal vesicles in sexually active men who were treated by α1-blockers for benign prostatic hyperplasia and its possible clinical application. This is a prospective cohort study from January 2015 to December 2016. We enrolled sexually active men above the age of 40 years having moderate to severe lower urinary tract symptoms (LUTS). We excluded patients with a history of prostate surgery, suspicious digital rectal examination findings, a serum prostate-specific antigen of >4 ng/dL, and a history of medication with anticholinergic, cholinergic, and diuretic agents. Patients were divided into groups A, B, and C based on the prescription of silodosin 8 mg, tamsulosin 0.4 mg, or alfuzosin 10 mg orally once for LUTS and at 4 and 12 weeks. The mean age was 54.8 years (41-68 years). Twelve weeks of treatment with silodosin, tamsulosin, and alfuzosin resulted in a significant improvement in the total International Prostate Symptom Score and the quality of life score (P <.001). The baseline erectile function scores were 26.4, 27.6, and 28.1, and the baseline overall satisfaction (OS) (International Index of Erectile Function [IIEF]-OS) scores were 7.1, 8.3, and 8.6 among groups A, B, and C, respectively. After 12 weeks of α1-blockers, the IIEF-erectile function scores were 24.0, 24.7, and 26.2, and the IIEF-OS scores were 6.4, 7.8, and 7.9. All 3 groups demonstrated a statistically significant enlargement of seminal vesicles after 12 weeks' treatment, most significant in group A patients (7.65-14.11 cc, P <.001). Alpha-blockers as silodosin, tamsulosin, and alfuzosin are a safe and effective tool in benign prostatic hyperplasia for improving LUTS and the quality of life. Loss of seminal emission with alpha-blockers appears as the cause of seminal vesicle enlargement. The exact mechanism of these findings needs further clinical and experimental research.

Suppressive effects of the antiandrogen agent, chlormadinone acetate and the 5α-reductase inhibitor, dutasteride on prostate weight and intraprostatic androgen levels in rats

The objectives of this study were to investigate whether chlormadinone acetate (CMA, Prostal, CAS 302-22-7) more markedly decreased ventral prostate and seminal vesicle weights and exerted more beneficial effects on intraprostatic androgen levels than dutasteride (DUT, CAS 164656-23-9) in rats. Dose-dependent inhibiting effects on prostate and seminal vesicle enlargement were observed after the 14-day administration of CMA (30, 100 mg/kg/day) and DUT (0.3, 1 mg/kg/day). The prostate atrophy rates calculated as the percentages relative to the vehicle-treated group were 50.5 and 67.9% with 30 and 100 mg/kg CMA and 34.9 and 37.0% with 0.3 and 1 mg/kg DUT, respectively, and the atrophying effect of CMA was significantly greater than that of DUT (p < 0.05). The results of 7-day administration were similar to those of 14-day administration. While CMA dose-dependently and significantly (p < 0.05) reduced the testosterone (T) and dihydrotestosterone (DHT) concentrations in prostate, DUT reduced the DHT concentration but markedly increased the T concentration (20-40 times). Even though it was carried out in rats, this study revealed for the first time that the antiandrogen CMA showed a stronger atrophying effect than the 5alpha-reductase inhibitor DUT on direct comparison. The difference between the atrophying effects of CMA and DUT is considered to be attributed to the present results that CMA reduced the concentrations of both androgens (T and DHT) in prostate but DUT did not, and the fact that CMA has a potent androgen receptor-blocking action but DUT does not.

Photoinduced Increase in Vesicle Size and Role of Photoresponsive Malachite Green Leuconitrile Derivative in Vesicle Fusion

The influence of photoirradiation on vesicles containing a Malachite Green leuconitrile derivative carrying a long alkyl chain, affording photogenerated amphiphilicity, was investigated. The photoresponsive Malachite Green leuconitrile derivative was embedded in the vesicle bilayer of two single-tailed amphiphiles with oppositely charged head groups consisting of cetyltrimethylammonium chloride (CTAC) and sodium octyl sulfate (SOS). Transmission electron microscopy, which was used for observing photoinduced structural change in the vesicles, demonstrated that photoirradiation of the vesicles containing the Malachite Green leuconitrile derivative increased the average size of the vesicle diameter from 116 to 243 nm in the [CTAC]/[SOS] = 0.48 system. The mechanism for vesicle enlargement was studied with fluorescent probe molecules. The photoinduced change in the vesicle size can be explained by the destabilization of the vesicle bilayer, which is perturbed by photogenerated amphiphilicity. In addition, it was shown that the fusion process arising from the destabilized bilayer contributed to the increase in vesicle size.

Case Report: Endoscopic Laser Lithotripsy of Seminal-Vesicle Stones

A 25-year-old man presented with painful ejaculation, an ejaculate volume of 0.75, and complaints of passing "granules" in the semen. Transrectal ultrasonography showed bilateral seminal vesicle enlargement. The patient underwent transurethral resection of the ejaculatory duct. The entry point of duct was resected using pure cutting current, resulting in the passage of multiple proteinaceous-appearing stones. Approximately 10 months later, the patient reported recurrent painful ejaculation and passage of granules in his semen. At cystoscopy, the ejaculatory duct openings were intubated with a cone-tipped catheter to perform bilateral seminal vesiculograms, which showed numerous mobile filling defects and a Steinstrasse appearance at the ejaculatory ducts. A 7F semirigid ureteroscope entered the lumen without difficulty over a guidewire, and the stones were fragmented with a 270-microm holmium laser fiber. The ejaculatory ducts were balloon dilated to 18F. To our knowledge, this is the first reported case where a ureteroscope was utilized to treat seminal-vesicle stones. The seminal vesiculogram proved to be extremely valuable in the diagnosis.

Coarse-Grained Transmembrane Proteins: Hydrophobic Matching, Aggregation, and Their Effect on Fusion

Molecular transport between organelles is predominantly governed by vesicle fission and fusion. Unlike experimental vesicles, the fused vesicles in molecular dynamics simulations do not become spherical readily, because the lipid and water distribution is inappropriate for the fused state and spontaneous amendment is slow. Here, we study the hypothesis that enhanced transport across the membrane of water, lipids, or both is required to produce spherical vesicles. This is done by adding several kinds of model proteins to fusing vesicles. The results show that equilibration of both water and lipid content is a requirement for spherical vesicles. In addition, the effect of these transmembrane proteins is studied in bilayers and vesicles, including investigations into hydrophobic matching and aggregation. Our simulations show that the level of aggregation does not only depend on hydrophobic mismatch, but also on protein shape. Additionally, one of the proteins promotes fusion by inducing pore formation. Incorporation of these proteins allows even flat membranes to fuse spontaneously. Moreover, we encountered a novel spontaneous vesicle enlargement mechanism we call the engulfing lobe, which may explain how lipids added to a vesicle solution are quickly incorporated into the inner monolayer.

ATP‐Dependent and drug‐inhibited vesicle enlargement reconstituted using synthetic lipids and recombinant proteins

A recombinant ECTO-NOX (tNOX) and a recombinant plasma membrane associated AAA-ATPase (ATPase Associated with Different Cellular Activities) were combined in stoichiometric proportions into liposomes together with albumin as a source of protein thiols. Large lamellar vesicles were formed from phosphatidylcholine, cholesterol and dicetyl phosphate in a molar ratio of 50:45:5, where the phosphatidylcholine was a 2:1 mixture of synthetic dimyristoyl and dipalmitoyl phosphatidylcholines. The lipids were dried to a film and reconstituted into vesicles by resuspension in buffer containing the recombinant proteins in equimolar ratios of 0.04 nmoles/mg lipid. In the presence of ATP, these vesicles enlarged in an ATP-dependent manner based on light-scattering measurements. Because the drug-inhibited ECTO-NOX protein, tNOX was utilized, the enlargement was inhibited by capsaicin, a quinone site tNOX inhibitor specific for tNOX. With the lipid vesicle systems, the recombinant ECTO-NOX, the recombinant AAA-ATPase, a source of protein thiols and ATP all were required. In control experiments, no ATP-dependent vesicle enlargement was observed with the AAA-ATPase or the ECTO-NOX protein alone. Also addition of ATP was without any effect when only the single proteins were incorporated into the lipid vesicles. A model has been developed whereby the plasma membrane AAA-ATPase is linked via disulfide bonds, formed and broken by the ECTO-NOX protein, to membrane structural proteins. Binding of ATP and subsequent hydrolysis and release of ADP would advance the ATPase hexamer ratchet thereby both thinning the membrane and increasing the vesicle surface.

ATP‐ and growth substance‐dependent cell‐free enlargement of plasma membrane vesicles from soybean

Growth hormone-responsive and nucleoside triphosphate-dependent enlargement of inside-out vesicles of plasma membranes from soybeans prepared by aqueous two-phase partition and everted by freezing and thawing has been achieved in a cell-free system. In the presence of 100 microM ATP in 40 mM HEPES buffer, pH 7, enlargement of isolated plasma membrane vesicles was accelerated by the synthetic plant growth factor, 2,4-dichlorophenoxyacetic acid (2,4-D), compared to ATP alone, 2,4-D alone or no additions. After 20 min with 1 microM 2,4-D, vesicles increased in diameter, 20% on average. Although vesicle diameters in the presence or absence of 2,4-D overlapped, the means were clearly separated. The 20% increases in diameter corresponded to a doubling of vesicle volume. Both 100 microM ATP and 1 microM 2,4-D were necessary to stimulate the cell-free vesicle enlargement. In the presence of 1 microM 2,4-D, enlargement observed with 100 microM ATP was greater than with either 10 microM ATP or 500 microM ATP alone. In the presence of 100 microM ATP, vesicle enlargement was proportional to the logarithm of 2,4-D concentration. With the growth-inactive 2,4-D analog, 2,3-D, no vesicle enlargement was observed either alone or in the presence of 100 microM ATP. Right side-out vesicles did not enlarge in response to either ATP, 2,4-D or the two in combination suggesting that the responsible ATP site was on the inside of the cell.

Wortmannin alters the intracellular trafficking of the bradykinin B2 receptor: role of phosphoinositide 3-kinase and Rab5.

Wortmannin reportedly induces the formation of enlarged cytoplasmic endosomes. Such vesicles were observed in a definite time window after wortmannin treatment (250 nM) in HEK-293 cells stably expressing a B2R (B2 receptor)--green fluorescent protein conjugate and other cell types. The alternative PI3K (phosphoinositide 3-kinase) inhibitor LY 294002 (100 microM) and a dominant-negative form of the enzyme (p85alpha DeltaiSH2) induce a more modest vesicle enlargement. PI3K inhibition by drugs did not affect agonist-induced [3H]arachidonate release. The wortmannin-induced formation of giant endosomes also involves Rab5 activity, since a dominant-negative form of this GTPase (Rab5 S34N) partially inhibits the wortmannin effect and a constitutively active form of Rab5 (Rab5 Q79L) induces the formation of enlarged endosomes. Moreover, agonist stimulation targeted B2R-green fluorescent protein towards the periphery of the giant vesicles and led to partial receptor degradation only in wortmannin-treated cells. Receptor degradation was decreased by protease inhibitors and by bafilomycin A1, a drug that inhibits lysosome function. Accumulation of fluorescent material inside the enlarged endosomes was observed in cells treated with bafilomycin A1, wortmannin and an agonist. [3H]Bradykinin binding was decreased in HEK-293 cells treated with both wortmannin and the agonist, but not with either separately. Furthermore, a wortmannin-induced functional down-regulation of B2R was observed in rabbit jugular veins after repeated agonist stimulation (contractility assay). This is the first report of a G-protein-coupled receptor down-regulation induced by an alteration of its usual routing in the cell. These results suggest that both PI3K and Rab5 influence B2R intracellular trafficking.

Phospholipid vesicle fusion induced by saposin C

Saposin C is a small Trp-free, multifunctional glycoprotein that enhances the hydrolytic activity of acid β-glucosidase in lysosomes. Saposin C’s functions have been shown to include neuritogenic/neuroprotection effects and membrane fusion induction. Here, the mechanism and kinetics of saposin C’s fusogenic activity were evaluated by fluorescence spectroscopic methods including dequenching, fluorescence resonance energy transfer, and stopped-flow analyses. Trp or dansyl groups were introduced as fluorescence reporters into selected sites of saposin C to serve as topological probes for protein–protein and protein–membrane interactions. Saposin C induction of liposomal vesicle enlargement was dependent upon anionic phospholipids and acidic pH. The initial fusion burst was completed in the timeframe of a few seconds to minutes and was dependent upon the unsaturated anionic phospholipid content. Two events were associated with saposin C–membrane interaction: membrane insertion of the saposin C terminal helices and reorientation of its central helical region. The latter conformational change likely exposed a binding site for saposins anchored on vesicles. Addition of selected saposin C peptides prior to intact saposin C in reaction mixtures abolished the liposomal fusion. These results indicated that saposin–membrane and saposin–saposin interactions are needed for the fusion process.

Amiloidosis localizada de vesículas seminales

Amyloidosis of the seminal vesicles is a common finding in autopsies, with increased incidence in older population. It is usually asymptomatic. We report a case of symptomatic localized amyloidosis of the seminal vesicles, with hemospermia and suprapubic pain. Diagnosis was achieved through ultrasound-guided transrectal biopsy. Systemic amyloidosis must be ruled out through proper evaluation. Seminal vesicle enlargement secondary to amyloid deposit may be misdiagnosed as carcinomatous invasion.

Visualization of actin dynamics during macropinocytosis and exocytosis.

Macropinocytosis of newly formed resides and exocytosis of post-lysosomes have been visualized using a green fluorescent protein probe that binds specifically to F-actin filaments. F-actin association with macropinocytosis begins as a V-shaped infolding of the membrane. Vesicle enlargement occurs through an inward movement of the proximal point of the V as well as an outward protrusion at the tip of the V to form an elongated invagination. The protrusion eventually closes at its distal margin to become a vesicle and is moved centripetally while recovering its circular shape. The vesicle loses its actin coat within 1 min after internalization. One hour later, post-lysosomal vesicles became weakly surrounded by actin while still cytoplasmic. Some of these vesicles moved to the plasma membrane, docked, and then expelled their contents. Slightly before the vesicle content began to disappear, an increase in F-actin association with the vesicle was observed. This was followed by rapid contraction of the vesicle and then disappearance of the actin signal once the internal content was released. These results show that dynamic changes in actin filament association with the vesicle membrane accompany both endocytosis and exocytosis.

Is transrectal ultrasonography a reliable diagnostic approach in ejaculatory duct sub-obstruction?

We studied the diagnostic predictive power of transrectal ultrasonography (TRUS) coupled with semen volume in cases of distal seminal tract sub-obstruction. As a gold standard for diagnosis we used seminal tract washout (STW). Non-azoospermic subjects (n = 112) were submitted to transrectal ultrasonography because of suspected excretory infertility or other andrological pathologies, before performing STW. STW indicated ejaculatory duct sub-obstruction in 36.6% of the patients. Seminal vesicle enlargement (anterior-posterior diameter > or = 15 mm) and seminal vesicle roundish anechoic areas (stasis) were the ultrasonographic anomalies more often associated with ejaculatory duct sub-obstruction. Stepwise logistic regression (SLR) analysis revealed that the ultrasonographic evidence of stasis was highly diagnostic only in the presence of a low semen volume (< or = 1.5 ml) and that ejaculatory duct sub-obstructions may be present but with no evidence of ultrasonographic anomalies. Therefore, TRUS is a useful approach for the treatment of suspected ejaculatory duct sub-obstruction, but is not a reliable diagnostic tool and, before performing transurethral surgery, STW should be mandatory.

Isopropanol vapor inhalation oncogenicity study in Fischer 344 rats and CD-1 mice.

The potential oncogenic effects of isopropanol, a widely used solvent, were investigated. Four groups of animals, each consisting of 75 CD-1 mice/sex and 75 Fischer 344 rats/sex, were exposed to isopropanol vapor (CAS No. 67-63-0) at target concentrations of 0 (filtered air control), 500, 2500, or 5000 ppm. Animals assigned to the core group (55 mice/sex/group and 65 rats/sex/group) were exposed for 6 hr/day, 5 consecutive days/week for at least 78 weeks for the mice or 104 weeks for the rats. Ten mice/sex/group and 10 rats/sex/group were assigned to an interim euthanasia group and were terminated during Weeks 54 and 73, respectively. In addition, 10 mice/sex/group were assigned to a recovery group and did not receive any further exposure following Week 53 but were retained until the core group of animals was euthanized. Transient signs of narcosis were observed for both mice and rats during exposure to 2500 and 5000 ppm and following exposure for mice from the 5000-ppm group. Increased mortality (100% versus 82% for controls) and a decreased mean survival time (577 days versus 631 days for controls) were noted for male rats from the 5000-ppm group. Increases in body weight and/or body weight gain were typically observed for both sexes of mice and rats from the 2500- and 5000-ppm groups throughout the study. Urinalysis and urine chemistry changes indicative of impaired kidney function (i.e., decreased osmolality and increased total protein, volume, and glucose) were noted for male rats from the 2500-ppm group as well as for male and female rats from the 5000-ppm group. At the interim euthanasia, a concentration-related increase in testes weight (absolute and relative as a percentage of body and brain weight) was observed for male rats. Concentration-related increases in absolute and relative liver weight (as a percentage of body weight) were observed for male and female mice. In addition, increased absolute and/or relative (as a percentage of body and brain weight) liver and kidney weights were observed for male and/or female rats from the 2500- and 5000-ppm groups. At necropsy, an increased incidence of seminal vesicle enlargement was observed grossly for male mice from the 2500- and 5000-ppm groups. Microscopically, some of the nonneoplastic lesions noted for mice included an increased incidence of ectasia of the seminal vesicles for male mice from the 2500- and 5000-ppm groups, minimal renal tubular proteinosis for male and female mice from all isopropanol groups, and renal tubular dilation for female mice from the 5000-ppm group. A number of nonneoplastic lesions were observed for male and female rats from the 2500- and 5000-ppm groups, with the most significant lesions being observed in the kidney and associated with chronic renal disease. The lesions noted with increased severity and/or frequency included mineralization, tubular dilation, glomerulosclerosis, interstitial nephritis, interstitial fibrosis, hydronephrosis, and transitional cell hyperplasia. The only tumor type increased in incidence during the study was interstitial cell adenomas of the testes in male rats. However, the increase in these adenomas was not believed to be exposure-related due to an unusually low incidence observed for the control group. There were no increased frequencies of neoplastic lesions noted for male or female mice or for female rats from any isopropanol exposure group. Chronic renal disease was attributed to be the main cause of death for male and female rats from the 5000-ppm group and was also considered to account for much of the mortality observed for male rats from the 2500-ppm group. In conclusion, the no-observed-effect level (NOEL) for toxic effects for both rats and mice was 500 ppm. The NOEL for oncogenicity effects for both mice and rats was determined to be greater than 5000 ppm.

Isopropanol Vapor Inhalation Oncogenicity Study in Fischer 344 Rats and CD-1 Mice

The potential oncogenic effects of isopropanol, a widely used solvent, were investigated. Four groups of animals, each consisting of 75 CD-1 mice/sex and 75 Fischer 344 rats/sex, were exposed to isopropanol vapor (CAS No. 67-63-0) at target concentrations of 0 (filtered air control), 500, 2500, or 5000 ppm. Animals assigned to the core group (55 mice/sex/group and 65 rats/sex/group) were exposed for 6 hr/day, 5 consecutive days/week for at least 78 weeks for the mice or 104 weeks for the rats. Ten mice/sex/group and 10 rats/sex/group were assigned to an interim euthanasia group and were terminated during Weeks 54 and 73, respectively. In addition, 10 mice/sex/group were assigned to a recovery group and did not receive any further exposure following Week 53 but were retained until the core group of animals was euthanized. Transient signs of narcosis were observed for both mice and rats during exposure to 2500 and 5000 ppm and following exposure for mice from the 5000-ppm group. Increased mortality (100% versus 82% for controls) and a decreased mean survival time (577 days versus 631 days for controls) were noted for male rats from the 5000-ppm group. Increases in body weight and/or body weight gain were typically observed for both sexes of mice and rats from the 2500- and 5000-ppm groups throughout the study. Urinalysis and urine chemistry changes indicative of impaired kidney function (i.e., decreased osmolality and increased total protein, volume, and glucose) were noted for male rats from the 2500-ppm group as well as for male and female rats from the 5000-ppm group. At the interim euthanasia, a concentration-related increase in testes weight (absolute and relative as a percentage of body and brain weight) was observed for male rats. Concentration-related increases in absolute and relative liver weight (as a percentage of body weight) were observed for male and female mice. In addition, increased absolute and/or relative (as a percentage of body and brain weight) liver and kidney weights were observed for male and/or female rats from the 2500- and 5000-ppm groups. At necropsy, an increased incidence of seminal vesicle enlargement was observed grossly for male mice from the 2500- and 5000-ppm groups. Microscopically, some of the nonneoplastic lesions noted for mice included an increased incidence of ectasia of the seminal vesicles for male mice from the 2500- and 5000-ppm groups, minimal renal tubular proteinosis for male and female mice from all isopropanol groups, and renal tubular dilation for female mice from the 5000-ppm group. A number of nonneoplastic lesions were observed for male and female rats from the 2500- and 5000-ppm groups, with the most significant lesions being observed in the kidney and associated with chronic renal disease. The lesions noted with increased severity and/or frequency included mineralization, tubular dilation, glomerulosclerosis, interstitial nephritis, interstitial fibrosis, hydronephrosis, and transitional cell hyperplasia. The only tumor type increased in incidence during the study was interstitial cell adenomas of the testes in male rats. However, the increase in these adenomas was not believed to be exposure-related due to an unusually low incidence observed for the control group. There were no increased frequencies of neoplastic lesions noted for male or female mice or for female rats from any isopropanol exposure group. Chronic renal disease was attributed to be the main cause of death for male and female rats from the 5000-ppm group and was also considered to account for much of the mortality observed for male rats from the 2500-ppm group. In conclusion, the no-observed-effect level (NOEL) for toxic effects for both rats and mice was 500 ppm. The NOEL for oncogenicity effects for both mice and rats was determined to be greater than 5000 ppm.

Establishment and Characterization of Testicular Cell Lines from MT-PVLT-10 Transgenic Mice

Males of the MT-PVLT-10 transgenic mouse line, which expresses the polyomavirus large T-antigen under the control of the metallothionein promoter, develop testicular adenomas and display seminal vesicle enlargement. Histological analysis of adenomatous testis indicates a predominance of Leydig cells, with few normal Sertoli cells or seminiferous tubules remaining. Primary cell cultures established from the testes of control nontransgenic animals (all ages) and young MT-PVLT-10 animals (before the appearance of any phenotype) quickly entered crisis and died. In contrast, permanent cell lines could be derived from pre- and postadenomatous testes from older MT-PVLT-10 mice. All primary cultures and cell lines expressed large T-antigen. A primary culture (D-37) derived from an MT-PVLT-10 male with normal testes but enlarged seminal vesicles has been maintained for over 2 years and experiments indicate that the D-37 culture is unable to form tumors in nude mice. In contrast, a primary culture (D-4) derived from adenomatous testes of an MT-PVLT-10 mouse is also immortal, but injection of this culture into nude mice consistently resulted in tumor formation. Cloning of the D-4 culture resulted in pure Sertoli or Leydig cell clones, neither of which could form tumor upon injection into nude mice. Injection of a mixture of both cell types did result in tumor formation, suggesting a dynamic interaction between these cell types in MT-PVLT-10-induced tumorigenesis.

Significance of ct-scan-detected seminal vesicle enlargement in prostate cancer A pilot study

The significance of CT-scan-detected seminal vesicle enlagement was investigated by correlating preoperative CT scans and pathologic findings for 25 patients undergoing radical prostatectomy. Seminal vesicle size was found to be a poor predictor of pathologic involvement when compared with tumor differentiation and obliteration of seminal vesicle angle.

The olivary pretectal nucleus: experimental anatomical studies in the rat.

The olivary pretectal nucleus: experimental anatomical studies in the rat.

Annual fish oogenesis: II. Formation of the secondary egg envelope

Elaborate surface ornamentation of the secondary egg envelope of the annual fishes, Cynolebias melanotaenia and C. ladigesi, is comprised of 250-Å components which are synthesized in the follicle cells during Stage 5 and are secreted during Stage 6. Tubules, due to their structure and electron density, act as naturally occurring tracers which can be used to localize their site of synthesis and path of intracellular transport. At Stage 5, follicle cells acquire the morphological features of a protein synthesizing-secreting cell. Appearance of a well-developed granular endoplasmic reticulum coincides with the initial appearance of tubular material. Tubular precursors first appear in the cisternae of the RER. These regions become dilated and seem to bud off to form vesicles. Vesicle enlargement occurs through continued synthesis or by fusion with other vesicles. Vesicles contain partially assembled tubules in a loose aggregation of disks and short rods. The limiting membrane of vesicles, even up to half the size of the nucleus, is uniformly studded with ribosomes. Late in Stage 5, the contents of the vesicles coalesce into compact granules in which 250-Å tubules have assembled. During Stage 6, shortly before fusing with the plasma membrane, the RER-derived vesicles appear to shed their ribosomes. Upon fusion, the vesicle discharges a discrete granule. The RER-derived vesicles transport tubular components directly from the site of synthesis to the exterior of the cell. Morphological evidence indicates that the pathway of intracellular transport and secretion bypasses the Golgi complex. Hexagonal close packing of the follicle cells seems to determine the spatial distribution of pattern in the secondary envelope. Generation of elaborate structures within the overall pattern results from the morphogenetic activity of individual cells. On the basis of structure, the secondary envelope constitutes a chorionic respiratory system similar to insect eggs. It probably functions as a “plastron” or physical gill.