Receptorial characterization of adrenergic neuroregulation of micturition, ejaculation and erection. An up-to-date review

In the dynamics of the lower urinary tract, further knowledge has been gained above all concerning distribution and characterization of the adrenoceptors. Moreover recent results of both experimental and clinical research have focused attention on the role of the peripheral adrenoceptors in seminal ejaculation and related disorders. On the other hand, norepinephrine has been accepted as the principal neurotransmitter in the control of penile detumescence and flaccidity. The rationale of applying such knowledge to minctional, erective and ejaculative disorders is discussed on the basis of a literature review as well as of our own studies on the topic.

Organization of the human CD40L gene: implications for molecular defects in X chromosome-linked hyper-IgM syndrome and prenatal diagnosis

Recently, CD40L has been identified as the gene responsible for X chromosome-linked hyper-IgM syndrome (HIGM1). CD40L on activated T cells from HIGM1 patients fails to bind B-cell CD40 molecules, and subsequent analysis of CD40L transcripts by reverse transcription PCR demonstrated coding region mutations in these patients. This approach, however, is of limited use for prenatal diagnosis of HIGM1 in the early-gestation fetus. In this report, we have defined the genomic structure of the CD40L gene, which is composed of five exons and four intervening introns. With this information, we have defined at the genomic level the CD40L gene abnormalities for three previously described HIGM1 patients who demonstrated clustered deletions in the CD40L coding region. These different deletions arose from three distinct mechanisms, including (i) a splice donor mutation with exon skipping, (ii) a splice acceptor mutation with utilization of a cryptic splice site, and (iii) a deletion/insertion event with the creation of a new splice acceptor site. In addition, we have performed prenatal evaluation of an 11-week-old fetus at risk for HIGM1. CD40L genomic clones provide a starting point for further studies of the genetic elements that control CD40L expression. Our knowledge of the CD40L gene structure will prove useful for the identification of additional mutations in HIGM1 and for performing genetic counseling about this disease.

[Calyceal diverticula: notes on endourological technique]

Percutaneous approach to complicated small caliceal diverticula is the first choice therapy. Generally, the open surgery is used large diverticula with renal parenchymal damage but, in selected cases, a percutaneous (PCN) treatment may be an effective alternative. The Authors report a case of inferior caliceal diverticulum associated to a parenchymal damage successfully treated using directed PCN management (electrical fulguration) and consequent injection of human fibrin glue.

ZNF75: isolation of a cDNA clone of the KRAB zinc finger gene subfamily mapped in YACs 1 Mb telomeric of HPRT

We have previously mapped a zinc finger genomic motif (ZNF75) to the Xq26 cytogenetic band by using a hybrid panel. Here, we report the isolation of the transcribed counterpart in a cDNA clone and its further localization. The cDNA clone, from a lung fibroblast library, is assembled from three exons, including a 289 amino acid (AA) long open reading frame containing a recently described motif, the Kruppel-associated box, 42 AA long, in exon 2. By comparison with other reported members of the subfamily, the exon-intron boundaries also appear to be very well conserved. Further analysis allowed us to map this gene 1 Mb downstream from the HPRT gene in the published YAC contig that extends across Xq26. Two other motifs, 87 and 78% homologous to ZNF75 at the amino acid level, were identified by PCR on total human DNA, but map outside Xq24-qter.

Type 2 vasopressin receptor gene, the gene responsible nephrogenic diabetes insipidus, maps to Xq28 close to the LICAM gene

Although long contigs have been assembled in Xq28, the interval between the anonymous probe St14 and the color vision locus is still incompletely defined. We report here that the recently cloned gene for type 2 vasopressin receptor (V2R) is physically linked to L1CAM using YACs and cosmids across about 180 kb of the region. Since it is known that L1CAM maps near the color pigment genes, this finding locates V2R in Xq28 in the area where nephrogenic diabetes insipidus (NDI) has been mapped by linkage analysis. The PFGE analysis of the clones positions V2R about 40 kb from the L1CAM gene in a region that appears to contain other unknown genes, since at least four putative CpG islands were identified by restriction analysis with rare cutter enzymes.

Mapping of two genes encoding isoforms of the actin binding protein ABP-280, a dystrophin like protein, to Xq28 and to chromosome 7

ABP-280 is a ubiquitous actin binding protein present in the cytoskeleton of many different cell types. ABP-280 was mapped to distal Xq28, 50-60 kb downstream of the Green Colour Pigment (GCP) genes. To establish if ABP-280 may be a candidate for one of the muscle disease localized by linkage analysis to distal Xq28 we looked for alternative forms of ABP-280 mRNA. Several different ABP-280 mRNAs were indeed identified: two are X-linked and are produced by alternative splicing of a small exon of 24 nucleotides. At least one additional gene encoding a RNA more than 70% identical to ABP-280 in the 1700 bp sequenced has also been found. It was mapped to chromosome 7. While both forms of the X-linked ABP-280 are ubiquitous, the gene on chromosome 7 is highly expressed only in skeletal muscle and heart. The two genes were therefore excellent candidates for the X-linked and for the autosomal dominant form of the Emery-Dreifuss Muscular Dystrophy (EDMD) both of which have been described. So far, however we were unable to demonstrate mutations in the coding region or affecting the alternative splicing of the X-linked form of ABP-280, in several patients studied, and we think that it is quite unlikely that this is the gene responsible for EDMD.

[Role of nitric oxide in the erectile mechanism]

Nitric oxide has been identified as an Endothelium-Derived Relaxing Factor (EDRF). Non adrenergic-non cholinergic nerves synthesise and release nitric oxide, thus modulating the arterial tone. Nitric oxide synthase exists either as a constitutive enzyme in many cell types and as an inducible form expressed under immunological stimulation. Nitric oxide is also involved in the non adrenergic-non cholinergic neurotransmission that leads to smooth muscle relaxation in the corpus cavernosum. Similarly nitric oxide induces reduction of cytosolic free Ca++ as a result of activation of the soluble form of guanylyl cyclase. VIP and nitric oxide may function as co-transmitters. Relaxation of the corpus cavernosum is blocked by methylene blue which inhibits cyclic GMP synthesis; so, high flow priapism refractory to medical and surgical treatments can be managed successfully by intracavernous methylene blue. Moreover it is suggested that enhanced alpha 1-adrenergic mediated constrictor tone and penile flaccidity in diabetic men may respond to exogenous generators of nitric oxide. We postulate that relaxation of the corpus cavernosum, started by nitric oxide in response to non adrenergic-non cholinergic neurotransmission, could be amplified and maintained by nitric oxide production as a result of platelet trapping in the corpus cavernosum during the first phase of the penile erection.

[Urothelial tumors and the extracellular matrix]

The network of both intra- and intercellular, either physical (bioconductive connectional system) and/or chemical signals, plays a significant role in the maintenance of tissue architecture and integrity of epithelial cell layers. The basement membrane is not only a static barrier but a dynamic regulator of the urothelium. Any change in the basement membrane can lead, by the extracellular matrix-cytoskeleton-nuclear matrix interaction, to altered gene regulation of the urothelial cells. Abnormal production and deposition or proteolytic degradation of the extracellular matrix components correlate with tumour stage and progression. In some experimental models, tissue inhibitors of metalloproteinases or anti-proteinase antibodies can abrogate the proteolytic activity of those matrix metalloproteinase enzymes (collagenase IV, cathepsin, stromelysin, etc.) which promote tumour invasion. Finally, the current researches investigating the use of biologic protein (e.g., TIMP-1 e-2; agents that affect angiogenesis and spread of neoplasias) are aimed at offer new therapeutic opportunities in oncology.

Isolation of a zinc finger motif (ZNF75) mapping on chromosome Xq26

We report here the partial characterization of a new human zinc finger (ZNF75) gene of the Kruppel type mapping to the long arm of the X chromosome. A cosmid clone was isolated from a library specific to the Xq24-qter region by hybridization to a degenerate oligonucleotide representing the link between two contigous fingers of the C2H2 type. The sequence of the pertinent cosmid fragments demonstrated five consecutive zinc finger motifs, all pertaining to the Kruppel family. A reading frame starting at least 75 amino acids before the first zinc finger and ending 11 amino acids after the last one was identified; comparison with other ZF genes suggests that this genomic fragment represents the carboxy-terminal exon of the gene. Homology of approximately 55% in the zinc finger region was detected with many zinc finger genes including mouse Zfp-35 and human ZFN7 cDNA clones. Mapping using a panel of sematic cell hybrids and chromosomal in situ hybridization localized the gene to Xq26, in a region not previously known to contain zinc finger genes.

A Case of Gonadal Stromal Tumour

Gonadal stromal tumor is a rare neoplasm of the testis. 10% of these tumors are malignant, but malignant histological criteria are not established. The principal therapy is orchidofuniculectomy while lynphadenectomy is for uncertain malignant neoplasm. Radiotherapy and antiblastic therapy sensitivity is poor.

Fidelity of a YAC clone in the region of human MCF-2 gene

A cosmid library was constructed from a YAC clone (XY311) carrying an insert of 650 kb from the F IX/mcf-2 region on human X chromosome. A contig of 200 kb that includes the mcf-2 gene and the genomic region downstream was assembled. Eighty kb of this contig represents a chromosome fragment already cloned and analyzed in detail with conventional restriction enzymes: comparison with this published map suggests that this region was correctly maintained during the procedure of YAC cloning. A discrepancy between the published map and the cloned YAC material was identified, but it resulted to be an EcoRI polymorphism present in the X3000.11 from which the YAC library was derived. The 3' portion of this contig, representing the telomeric end of the YAC XY311, provides new cosmid material for further analysis of the region downstream of the mcf 2 locus.

Secretion of alpha-subunit and intact gonadotropins after surgical and chemical castration

In order to investigate the regulatory mechanisms involved in the secretion of glycoprotein hormones, we studied the secretory patterns of LH, FSH and alpha-subunit in hypogonadal men. Three groups of patients with carcinoma of the prostate were studied both before and 15 days after orchiectomy, or the initiation of ketoconazole or LHRH analog therapy. There were significant increases (P less than 0.01) in LH and alpha-subunit levels in the patients treated with orchiectomy and ketoconazole, but FSH levels increased only in the orchiectomized patients. After LHRH analog treatment, LH levels were significantly decreased when assayed with an immunoradiometric assay method which does not cross-react with alpha-subunit. FSH values were significantly lower than pretreatment levels, while alpha-subunit levels remained significantly elevated throughout the study period. These results demonstrate that after both chemical (ketoconazole) and surgical castration, the secretion of alpha subunit follows a pattern which is tightly correlated with that of LH but not of FSH. However, after LHRH analog treatment, alpha-subunit appears to be the sole secretory product of the gonadotroph.