Decoding bladder state from pudendal intraneural signals in pigs.

Neuroprosthetic devices used for the treatment of lower urinary tract dysfunction, such as incontinence or urinary retention, apply a pre-set continuous, open-loop stimulation paradigm, which can cause voiding dysfunctions due to neural adaptation. In the literature, conditional, closed-loop stimulation paradigms have been shown to increase bladder capacity and voiding efficacy compared to continuous stimulation. Current limitations to the implementation of the closed-loop stimulation paradigm include the lack of robust and real-time decoding strategies for the bladder fullness state. We recorded intraneural pudendal nerve signals in five anesthetized pigs. Three bladder-filling states, corresponding to empty, full, and micturition, were decoded using the Random Forest classifier. The decoding algorithm showed a mean balanced accuracy above 86.67% among the three classes for all five animals. Our approach could represent an important step toward the implementation of an adaptive real-time closed-loop stimulation protocol for pudendal nerve modulation, paving the way for the design of an assisted-as-needed neuroprosthesis.

Treatments for erectile dysfunction in spinal cord patients: alternatives to phosphodiesterase type 5 inhibitors? A review study.

STUDY DESIGN: Review study. OBJECTIVES: Alternative treatments to oral phosphodiesterase type 5 inhibitors (PDE5Is) in individuals with spinal cord lesions (SCLs) and erectile dysfunction (ED). SETTING: Italy. METHODS: Research clinical trials (1999-2014). RESULTS: Twelve studies were selected. One article documented that 76% of subjects reached satisfactory sexual intercourse (SI) using intracavernosal injection of vasoactive medications (papaverine and prostaglandin E1). One study regarding perineal training showed a significant increase (P<0.05) in penile tumescence in 10 individuals with preserved sacral segment. Two studies reported contrasting results on erectile function (EF) using various dosages of oral fampridine (25-40 mg). Furthermore, 95.1% of patients on fampridine 25 mg experienced drawbacks. Disappointing findings were found with intraurethral alprostadil (125-1000 µg) and sublingual apomorphine 3 mg. Two studies concerning penile prosthesis reported valid SI more than 75% of the time with a mean follow-up of 11 years, although around 15% of individuals showed side effects. As for surgical treatments, 88% of males submitted to Brindley sacral anterior root stimulator after sacral dorsal rhizotomy achieved valid erection up to 8 years following the procedure. Three studies documented the impact of definitive sacral neuromodulation implant (Medtronic, Minneapolis, MN, USA) also on EF. After surgery, 20-37.5% of patients with ED recovered normal EF. CONCLUSIONS: Data are scant on the efficacy of ED treatments for SCL subjects who did not respond to PDE5Is. Further research should investigate the effects of any SCL treatments even when they are not strictly used for neurogenic sexual dysfunction.

Sacral neuromodulation for neurogenic non-obstructive urinary retention in incomplete spinal cord patients: a ten-year follow-up single-centre experience.

OBJECTIVE: To determine the success rate of percutaneous first stage of sacral neuromodulation (SNM) and the efficacy and safety of permanent SNM for incomplete spinal cord lesion (SCL) patients suffering from chronic neurogenic non-obstructive urinary retention (N-NOR). METHOD: From January 2003 to December 2012, 85 individuals underwent the percutaneous first stage of SNM. Subsequently, only responders who reached a concomitant reduction by at least 50% of volume per catheterization and in the number of catheterizations per day comparing their 7-day voiding diaries at baseline underwent permanent SNM. Final follow-up was conducted by April 2013. RESULTS: Thirty-six individuals responded to percutaneous first stage of SNM. Post-surgery urodynamics documented all patients experiencing first sensation of bladder filling. A statistically significant increase in Qmax ml per sec and decrease in post-voiding residual urine per ml were documented. (P<0.01). First sensation of bladder filling at baseline represented a statistically significant parameter for the success of the first stage SNM (P<0.05). Eleven out of 34 patients at follow-ups were 'inconstant responders' because they returned to similar baseline voiding symptoms, but responded again with an implant on the controlateral S3 sacral root. Two failed twice and responded once again after an S4 sacral root implant. All but one failure occurred more than 3 years after the previous implant. Other drawbacks were resolved telemetrically. CONCLUSIONS: Research is needed to increase the success rate of the first stage SNM on incomplete SCL patients with N-NOR. Permanent SNM is highly efficacious in the medium follow-up.

A retrospective study on female urological surgeries over the 10 years following spinal cord lesion.

OBJECTIVES: To evaluate the efficacy and safety over a 10-year period of any urological operations required by female patients with spinal cord lesions (SCLs). METHODS: Retrospective study of urological surgeries from our database performed on females with SCLs from 2001 to 2002. Surgery efficacy for neurogenic lower urinary tract dysfunctions (N-LUTDs) was evaluated by comparing 7-day voiding diaries pre- and post-surgeries, while individual investigations were done pre- and post-surgery to evaluate urological complications. Drawbacks were assessed. RESULTS: Thirty-eight out of 69 patients underwent one or more urological procedures. Twenty-one out of 42 patients with suprasacral lesions underwent interventions for N-LUTD. The main surgical treatment was endoscopic detrusor infiltration of botulinum-A (Botox 300 UI or Dysport 750 UI) performed 107 times on 15 subjects using aseptic intermittent catheterizations for neurogenic overactive bladder. Mean efficacy duration was 9.2 months. Six females with infrasacral lesions underwent at least one intervention for N-LUTD. Two females in each group underwent tension-free vaginal tape for stress urinary incontinence (SUI), reducing episodes per week of SUI by >90% after 5 years. The most serious urological complication was active vesico-ureteral reflux (VUR) in three patients, treated endoscopically with submucosal injection of Macroplastique. No VUR recurrence was detected during a 6-year follow-up. All bladder stones (five cases) and renal calculi (five cases) were treated with endoscopic transurethrally electrohydraulic lithotripsy and extracorporeal shock-wave lithotripsy, respectively. Overall, no serious drawbacks were observed. CONCLUSIONS: Mini-invasive surgeries were exclusively used to address urological issues in chronic SCL patients.

Intravesical electrostimulation versus sacral neuromodulation for incomplete spinal cord patients suffering from neurogenic non-obstructive urinary retention.

OBJECTIVES: To compare the efficacy of intravesical electrostimulation (IVES) versus sacral neuromodulation (SNM) in patients with incomplete spinal cord lesions (SCL) and neurogenic non-obstructive urinary retention (N-NOR). METHODS: In this retrospective study, 77 N-NOR patients underwent IVES (minimum 28 sessions), then after returning to voiding baseline symptoms, percutaneous first stage of SNM (lasting for minimum 4 weeks). After the two neuromodulation treatments, responders were categorized as patients experiencing both a 50% reduction of volume per catheterization per ml and a 50% reduction in number of catheterizations per day when comparing the 7-day voiding diaries at the end of both procedures to baselines. New urodynamics were performed subsequently. Responders to first stage of SNM underwent permanent SNM. RESULTS: Forty-eight patients responded to neither of the treatments, whereas 29 responded to both IVES and first-stage SNM. No significant statistical differences (P>0.05) were detected in the voiding diaries. Following the two procedures, the first sensation of bladder filling was either maintained or recovered by all responders, whereas the same 11 patients reached a bladder contractility index of >100. The 29 IVES responders lost their clinical benefits in a mean follow-up of 9.6 months. Only 10 out of the 29 patients became nonresponsive to permanent SNM, in a mean follow-up of 54 months. CONCLUSION: A strict correlation in terms of clinical and urodynamic patterns was demonstrated in patients with incomplete SCL and N-NOR, following IVES and first stage of SNM. However, voiding improvement through IVES was short-term when compared with the effects of permanent SNM.

Genomic organization of a new candidate tumor suppressor gene, LRP1B.

LRP1B is a novel candidate tumor suppressor gene that is inactivated by genetic and transcript alterations in nearly 50% of non-small-cell lung cancer cell lines. The gene-encoded protein is highly homologous to the gigantic lipoprotein receptor-related protein 1 (LRP1) that belongs to the family of low-density lipoprotein receptors. Using a combination of PCR-based genome walking and long-distance interexon PCR, we have determined the genomic organization of LRP1B and built a contiguous array of BAC clones spanning this gene. A total of 91 exons, varying in size from 77 bases (exon 87) to 1899 bases (exon 91), were identified in the more than 500-kb-long gene sequence. Comparative analysis of the genomic structures of LRP1B and the homologous LRP1 gene revealed a striking similarity in the location and sizes of their exons.

LRP-DIT, a putative endocytic receptor gene, is frequently inactivated in non-small cell lung cancer cell lines.

A variety of studies suggest that allelic losses at chromosome 2q are associated with aggressive behavior of various forms of human neoplasia. Using a probe to detect homozygous deletions on chromosome 2q21.2 in kidney and bladder cancer cell lines, we identified a new candidate tumor suppressor gene, lipoprotein receptor-related protein-deleted in tumors (LRP-DIT). The predicted LRP-DIT product of 4599 amino acids has extensive homology to a gigantic receptor, LRP1, which mediates endocytosis of multiple proteins from the cell surface. Homozygous deletions in LRP-DIT were detected in 17% (4 of 23) of non-small cell lung cancer (NSCLC) cell lines. The expression of only abnormal transcripts missing portions of the LRP-DIT sequence was demonstrated in an additional 30% (11 of 36) of NSCLC lines. Finally, a missense mutation at codon 3157 was detected in one of four NSCLC lines tested for the large open reading frame. In contrast, no LRP-DIT alterations were identified in a major fraction of SCLC cell lines, indicating that this gene is preferentially inactivated in one histological type of lung cancer. Our data suggest that inactivation of LRP-DIT occurs in at least 40% of NSCLC lines and thus may play an important role in tumorigenesis of NSCLCs.

The gene encoding the mitogen-responsive phosphoprotein Dab2 is differentially regulated by GATA-6 and GATA-4 in the visceral endoderm.

Gene targeting studies have demonstrated that the zinc finger transcription factor GATA-6 lies upstream in a transcriptional cascade that controls differentiation of the visceral endoderm. To understand the function of GATA-6 in the visceral endoderm and to identify genes regulated by GATA-6 in this tissue, subtractive hybridization was performed using template cDNAs derived from differentiated wild-type embryonic stem (ES) cells and GATA-6(-/-) ES cells, respectively. These analyses revealed that the gene encoding Dab2, a mitogen-responsive phosphoprotein, is differentially expressed in wild-type and GATA-6-deficient ES cells. Consistent with these findings, Dab2 is expressed in the visceral endoderm of wild-type embryos but not in the visceral endoderm of GATA-6-deficient embryos. Cotransfection experiments demonstrate that the human Dab2 promoter can be transactivated by forced expression of GATA-6 in NIH-3T3 cells. In contrast, forced expression of GATA-4 does not transactivate the human Dab2 promoter and Dab2 is expressed in the visceral endoderm of GATA-4 null embryos. Surprisingly, the specificity of GATA-6-induced transactivation of the Dab2 promoter is not mediated through its zinc finger DNA-binding domain. Taken together, these data demonstrate that the mitogen-responsive phosphoprotein Dab2 is a downstream target of GATA-6 in the visceral endoderm. Moreover, these data demonstrate that molecular mechanisms have evolved that direct, and distinguish, the functional specificity of GATA family members when they are developmentally coexpressed.

Cloning and expression of the programmed cell death regulator Bad in the rat brain.

The Bcl-2 family of proteins consists of both antagonists (e.g. Bcl-2) and agonists (e.g. Bax) that regulate apoptosis and compete through dimerization. In the present study we cloned the cDNA encoding the rat brain BAD, a distant member of the Bcl-2 family that was shown to promote cell death. The cloned cDNA encoded a protein of 205 amino acids, containing three putative Bcl-2 homology domains (BH1, BH2 and BH3) and no C-terminal signal-anchor sequence. The predicted amino acid sequence was identical to the Bad-cDNA recently cloned from the rat ovary with the exception of a stretch of six amino acids, thus indicating the existence of two Bad alternative splice variants or a sequence artifact in the rat ovary Bad-cDNA. Immunohistochemical analysis in the rat brain revealed the exclusive expression of Bad in the epithelial cells of the choroid plexus, a result which is consistent with a very specialized function of Bad in the brain.

Late memory-related genes in the hippocampus revealed by RNA fingerprinting.

Although long-term memory is thought to require a cellular program of gene expression and increased protein synthesis, the identity of proteins critical for associative memory is largely unknown. We used RNA fingerprinting to identify candidate memory-related genes (MRGs), which were up-regulated in the hippocampus of water maze-trained rats, a brain area that is critically involved in spatial learning. Two of the original 10 candidate genes implicated by RNA fingerprinting, the rat homolog of the ryanodine receptor type-2 and glutamate dehydrogenase (EC 1.4.1.3), were further investigated by Northern blot analysis, reverse transcription-PCR, and in situ hybridization and confirmed as MRGs with distinct temporal and regional expression. Successive RNA screening as illustrated here may help to reveal a spectrum of MRGs as they appear in distinct domains of memory storage.

Pituitary adenylate cyclase activating polypeptide prevents apoptosis in cultured cerebellar granule neurons.

The two forms of pituitary adenylate cyclase-activating polypeptide, PACAP27 and PACAP38, are two neuropeptide hormones related to the vasoactive intestinal peptide/secretin/ glucagon family of peptides. PACAP receptors that are positively coupled to adenylyl cyclase and phospholipase C have been identified in cultured cerebellar granule cells. Using the reverse transcription-polymerase chain reaction methodology, we demonstrated the expression of the PACAP-R and PACAP-R-hop mRNAs in cultured granule cells. When grown in the absence of serum or in low K+ concentrations, these neurons underwent apoptosis, a naturally occurring process characterized by cell shrinkage and internucleosomal DNA cleavage. We used these models of programmed cell death to study the relationship between PACAP receptor activation and neuronal apoptosis. Treatment with PACAP27 and PACAP38 reduced the development of apoptosis in a dose-dependent manner. The neuroprotective activity of PACAP was mimicked by high concentrations of vasoactive intestinal peptide or forskolin but not by carbamylcholine. Thus, we suggest that the activation of type I PACAP receptors may contribute to the survival of cerebellar granule neurons.

Behavioral and neurochemical alterations induced by reversible conductive hearing loss in aged male rats.

Eighteen months old male rats of the Sprague-Dawley strain were subjected to a reversible conductive hearing loss (HL) or a sham operation. A series of behavioral tests performed 3 months after surgery, revealed a sustained deficit in learning and memory capacity and a marked depressive attitude of rats with HL. At this time, a group of these animals were allowed to recover from HL for 1 month and were again tested behaviorally compared to those with persistent auditory deficit. A better performance at the active and passive avoidance tests and normal responsiveness to the despair test was found in animals with recovered hearing capacity as compared to those with persistent HL. A biochemical analysis revealed a decrease of dopamine and homovanillic acid content and of choline-acetyltransferase and acetylcholinesterase activity in the striatum and hippocampus of animals with persistent HL as compared to those with recovered auditory deficit. These data suggest that persistent auditory deafferentation affects cognitive mechanism in old rats in a reversible manner.