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Biomedical subjects

G Morelli

Publications and source records attributed to G Morelli.

At least 73 records · Page 4Linked to original sources
PubMed1996

The Arabidopsis Athb-10 (GLABRA2) is an HD-Zip protein required for regulation of root hair development.

Homeodomain-leucine zipper (HD-Zip) proteins are putative transcription factors identified only in plants. Related Arabidopsis homeobox genes, isolated by virtue of sequence conservation within the helix-3 region of the homeodomain, fall into four families based on sequence similarity. This paper reports the characterization of Athb-10, a 747 amino acid protein belonging to the fourth HD-ZIP family. The studies indicate that, although less conserved, the leucine zipper of Athb-10 can functionally replace that of Athb-2 in an in vitro DNA-binding assay. Gene mapping experiments and sequence comparison analysis revealed that Athb-10 corresponds to GLABRA2, a homeodomain protein involved in trichome development. The mRNA expression analysis revealed that Athb-10/GLABRA2 is expressed not only in trichome-bearing organs, but also in the root. The analysis of wild-type and mutant plants showed that the Athb-10/GLABRA2 gene expression in the aerial part of the plant and in the root is affected by mutations at the TTG locus. Morphological analysis of the g/2-1 mutant revealed that the gene is necessary not only for local outgrowth of the trichome, but also for the regulation of root hair development in a subset of epidermal cells. Interestingly, the development of root hair cells in a position normally occupied by non-hair cells is dependent upon the ethylene regime in which the gl2-1 plants are grown. Sequence analysis of the gl2-1 allele revealed that the mutant gene encodes a truncated protein that might still retain a partial activity responsible for the formation of aborted trichomes and for the ethylene-dependent regulation of root hair formation.

Amino Acid Sequence↗
PubMed1996

Long-term intracavernous self-injection with prostaglandin E1 for the treatment of erectile dysfunction.

Intracavernous self-injection with vasoactive drugs has become a widely accepted treatment for erectile dysfunctions (ED). Sixty-eight patients affected by ED have been followed during long-term (at least 1 year) treatment with intracavernous prostaglandin E1. Each patient underwent a penile dynamic ultrasound examination using a high-definition probe (13 MHz) before and during the treatment. The drop-out rate was 8.8%. An improvement in spontaneous erections was reported by 13% of patients. The onset of fibrotic nodules occurred in three (4.4%) patients. In one of the latter cases the occurrence of nodules could be related to the frequency and dose of the drug administered, whereas in the other two cases no such correlation could be hypothesized. These findings draw attention to this possible side-effect of long-term treatment with PGE1.

Adult↗
PubMed1996

Transperineal biopsy leads to the diagnosis of genitourinary neurofibromatosis in association with a congenital malformation of the urinary tract.

OBJECTIVE: A case of genitourinary fibromatosis with associated anomalies is presented. METHODS: Clinical evaluation included ultrasonography, urography, CT scan and MR image. Ultrasonography-guided perineal biopsy was performed with a 14-gauge Tru-cut needle. RESULTS: Rectal examination revealed a very hard prostatic mass in the 22-year-old patient. The histological result and clinical data indicated the diagnosis of genitourinary von Recklinghausen disease. CONCLUSION: We report a very rare case of genitourinary neurofibromatosis associated with congenital anomalies of the urinary tract. The diagnosis was obtained with US-guided transperineal biopsy.

Adult↗
PubMed1996

Urodynamic evaluation of urinary incontinence following radical prostatectomy: our experience.

Thirty-four patients after retropubic radical prostatectomy, were evaluated with urodynamic studies. Patients were divided in three groups depending on the degree of urinary continence. A statistically significant difference was found between different groups for the mean functional profile length and maximal urethral closure pressure. Detrusor instability was detected in 11 patients with moderate incontinence and in 1 patient with severe incontinence. Neither differences of age, previous prostatic surgery, tumour extension, nor preservation of the neurovascular bundles had any significant influence on recovery of continence.

Aged↗
PubMed1995

Light induction of the clock-controlled gene ccg-1 is not transduced through the circadian clock in Neurospora crassa.

Ambient light and the circadian clock have been shown to be capable of acting either independently or in an interrelated fashion to regulate the expression of conidiation in the ascomycete fungus Neurospora crassa. Recently several molecular correlates of the circadian clock have been identified in the form of the morning-specific clock-controlled genes ccg-1 and ccg-2. In this paper we report studies on the regulation of ccg-1, an abundantly expressed gene displaying complex regulation. Consistent with an emerging consensus for clock-controlled genes and conidiation genes in Neurospora, we report that ccg-1 expression is induced by light, and show that this induction is independent of the direct effects of light on the circadian clock. Although circadian regulation of the gene is lost in strains lacking a functional clock, expression of ccg-1 is still not constitutive, but rather fluctuates in concert with changes in developmental potential seen in such strains. Light induction of ccg-1 requires the products of the Neurospora wc-1 and wc-2 genes, but surprisingly the requirement for wc-2 is suppressed in conditional mutants of cot-1, a gene that encodes, a cAMP-dependent protein kinase. These data provide insight into a complex regulatory web, involving at least circadian clock control, light control, metabolic control, and very probably developmental regulation, that governs the expression of ccg-1.

Blotting, Northern↗
PubMed1995

A cDNA encoding Arabidopsis thaliana cytoplasmic ribosomal protein L18.

A cDNA encoding ribosomal (r) protein L18 of Arabidopsis thaliana (At) was isolated and characterized. The nucleotide sequence contains a 563-bp open reading frame that encodes a 20.9-kDa basic protein. Amino-acid comparison indicated that the predicted L18 r-protein of At has a high degree of homology with L18 of distantly related organisms such as yeast, Xenopus laevis and rat. Genomic DNA analysis suggested that L18 is encoded by a single locus in At. An mRNA of approx. 0.9 kb is detected in all the tissues and developmental stages analyzed.

Arabidopsis↗
PubMed1995

Design of metal ion binding peptides.

Two cyclic and branched peptides (PLA and AZU) were synthesized with the aim of reproducing the active site of the blue copper proteins plastocyanin and azurin. Both peptides, designed on the basis of the x-ray structures of Poplar plastocyanin and Alcaligenes denitrificans azurin, contain the same coordinating residues of the parent native proteins. The visible spectra of PLA in the presence of equimolar amount of Cu(II) strongly support the interaction between the peptide and copper(II) ion. The CD titration of AZU with the Hg(II) ion indicates for the formation of two species, [AZUHg]+ and [AZUHg2]3+ having binding constants (Keq) of 3.10(6) and 2.10(4) M-1, respectively.

Amino Acid Sequence↗
PubMed1995

Assessment of normal testis growth by quantitative texture analysis of 2-D echo images.

Six phases summarize the evolution of the healthy male gonad. Qualitative examination of two-dimensional echograms detects tonal differences at different ages of the testes. However, routine qualitative evaluation of the echograms is too subjective and dependent upon the scanner controls; on the other hand, simple morphology reports are not sufficient to establish the correct histologic and physiologic evolution. So far computer-assisted quantitative analysis of ultrasonic images has been successful in the characterization of tissues based on their echographic properties; thus this approach could be suitable for an accurate identification of the age of healthy testis. Sixty-two normal subjects, ranked in six groups according to age, underwent echographic examination in standard conditions. Echograms were digitized and analysed by means of well-established algorithms for first and second order statistics. Significant differences in tonal features were found able to discriminate among different ages, in agreement with the qualitative analysis and the histologic reports. Furthermore, some second order analysis features exhibit statistically significant alterations of the micro-structural organisation of the echo patterns consequent to changes of the configuration of the ultrasonic targets, that is, of the gonad's histology. In conclusion, quantitative analysis of echograms can provide a tool for a better assessment of normal testis evolution than the qualitative approach.

Adult↗
PubMed1995

Symptomatic adrenal myelolipoma: therapeutic considerations.

Four cases of symptomatic myelolipoma of the adrenal gland are presented. Three were treated at laparotomy and one with a laparoscopic approach. On the basis of these four cases we discuss the aetiology, pathogenesis, clinical manifestations, diagnosis and treatment of this rare disease. We also report the follow-up of a patient with bilateral myelolipoma, who underwent monolateral excision. We conclude that myelolipoma, if correctly diagnosed, can be treated conservatively with careful follow-up, limiting surgery to symptomatic cases.

Adrenal Gland Neoplasms↗
PubMed1995

Ectopic expression of the Arabidopsis transcriptional activator Athb-1 alters leaf cell fate in tobacco.

The Arabidopsis thaliana Athb-1 is a homeobox gene of unknown function. By analogy with homeobox genes of other organisms, its gene product, Athb-1, is most likely a transcription factor involved in developmental processes. We constructed a series of Athb-1-derived genes to examine the roles of Athb-1 in transcriptional regulation and plant development. Athb-1 was found to transactivate a promoter linked to a specific DNA binding site by transient expression assays. In transgenic tobacco plants, overexpression of Athb-1 or its chimeric derivatives with heterologous transactivating domains of the yeast transcription factor GAL4 or herpes simplex virus transcription factor VP16 conferred deetiolated phenotypes in the dark, including cotyledon expansion, true leaf development, and an inhibition of hypocotyl elongation. Expression of Athb-1 or the two chimeric derivatives also affected the development of palisade parenchyma under normal growth conditions, resulting in light green sectors in leaves and cotyledons, whereas other organs in the transgenic plants remained normal. Both developmental phenotypes were induced by glucocorticoid in transgenic plants expressing a chimeric transcription factor comprising the Athb-1 DNA binding domain, the VP16 transactivating domain, and the glucocorticoid receptor domain. Plants with severe inducible phenotypes showed additional abnormality in cotyledon expansion. Our results suggest that Athb-1 is a transcription activator involved in leaf development.

Arabidopsis↗
PubMed1995

The expression of the Athb-8 homeobox gene is restricted to provascular cells in Arabidopsis thaliana.

We have characterized an Arabidopsis homeobox gene coding for a putative DNA binding protein that represents an early marker for vascular development. The full-length cDNA encodes a protein of 833 amino acids that we have designated Athb-8; it contains the conserved DNA binding domain that characterizes the HD-Zip family of transcription factors. RNA analysis showed that the Athb-8 gene is expressed during the vegetative and the reproductive phases of plant growth. A higher steady-state level of the Athb-8 mRNA was found in flowering stem and root. In situ mRNA analysis of Arabidopsis plants demonstrated that Athb-8 expression is restricted to the procambial cells of embryo and developing organs. Moreover, Athb-8-GUS expression was found in single parenchyma cells which are differentiating into tracheary elements in wounded tobacco transgenic plants. Finally, we showed that the auxin, indole-3-acetic acid, which is involved in vascular development and differentiation, modulates the expression of the gene. Taken together, these results suggest that Athb-8 might be a regulator of vascular development in Arabidopsis thaliana.

Amino Acid Sequence↗
PubMed1995

Sarcoidosis: single bulky mesenteric lymph node mimicking a lymphoma.

A previously healthy man presented with acute abdominal pain that extended from the left lumbar area to the left iliac fossa and to the omolateral testicular region. Abdominal ultrasonography and CT scan showed a bulky mesenteric mass and mesenteric, paraaortic, and paracaval lymph nodes. Biopsy specimens of the mass revealed non caseating granulomas. Chest CT scan and 67Gallium thoracic scan demonstrated lymph node and parenchymal pulmonary involvement. Bronchoalveolar lavage (BAL) confirmed the presence of a low intensity alveolitis. Serum angiotensin converting enzyme (SACE) level was elevated. Two years after steroid therapy, markers of disease activity and abdominal ultrasonography are in the normal range.

Adult↗
PubMed1994

Immunogenicity and evolutionary variability of epitopes within IgA1 protease from serogroup A Neisseria meningitidis.

Five murine epitopes were defined and mapped within IgA1 protease produced by Neisseria meningitidis. Epitopes 1 and 2 were present in IgA1 protease from all strains, and from Neisseria gonorrhoeae. Epitopes 3 through to 5 varied between subgroups of serogroup A meningococci, but have remained constant over decades within the subgroups, except for epitope 4, which changed between 1983 and 1987 during the spread of subgroup III meningococci from Asia to Africa. Binding of monoclonal antibodies to epitopes 1, 4 and 5 neutralized enzymatic function. Human sera containing antibodies to IgA1 protease as a result of natural infection inhibited binding of monoclonal antibodies to epitope 4 but not to the other epitopes.

Animals↗
PubMed1994

Molecular characterization of upstream regulatory sequences controlling the photoinduced expression of the albino-3 gene of Neurospora crassa.

In the filamentous fungus Neurospora crassa the biosynthesis of carotenoids is regulated by blue light, principally through transcriptional activation of some key genes in the carotenogenic enzymatic pathway. Here we report the characterization of the photoinducible promoter of the albino-3 (al-3) gene, encoding GGPP synthase. We have modified the 5' non-coding sequence of the cloned al-3 gene by deletion and site-directed mutagenesis, and we have tested the residual photoinducibility of the different constructs by transformation and subsequent analysis of gene expression in dark-grown and light-induced mycelia. The results indicate that a promoter region between positions -226 and -55 contains all the necessary information for blue light photoinduction. Multiple regulatory elements are involved in the regulated expression of the al-3 gene. One (termed the APE element) is important for the light-induction switch on of the gene and a second belongs to the CCAAT boxes family. The putative APE element is also found in the promoter of other N. crassa photoinducible genes.

Alkyl and Aryl Transferases↗
PubMed1994

The porA gene in serogroup A meningococci: evolutionary stability and mechanism of genetic variation.

Molecular analyses were applied to the genes encoding variants of the serosubtyping antigen, the class 1 outer membrane protein (PorA), from 55 serogroup A Neisseria meningitidis strains. These genes were evolutionarily stable and exhibited a limited range of genetic variation, primarily generated by recombination. Translation of the gene sequences revealed a total of 19 distinct amino acid sequences in the variable regions of the protein, 6 of which were not recognized by currently available serosubtyping monoclonal antibodies. Knowledge of these amino acid sequences permitted a rational re-assignment of serosubtype names. Comparison of the complete genes with porA gene sequences from serogroup B and C meningococci showed that serogroup A possessed a limited number of the possible porA genes from a globally distributed gene pool. Each serogroup A subgroup was characterized by one of four porA gene types, probably acquired upon subgroup divergence, which was stable over periods of decades and during epidemiological spread. Comparison with other variable genes (pil and iga) indicated that the three alleles were independently assorted within the subgroup, suggesting that their gene types were older than the subgroups in which they occurred.

Alleles↗
PubMed1994

[Echo-color Doppler in acute scrotum].

The Authors report their experience about the use of color doppler US in the diagnosis of acute scrotal pain. Their data show the importance and the central role of color Doppler US to distinguish between phlogosis and ischemia.

Acute Disease↗
PubMed1993

The Athb-1 and -2 HD-Zip domains homodimerize forming complexes of different DNA binding specificities.

The Arabidopsis Athb-1 and -2 proteins are characterized by the presence of a homeodomain (HD) with a closely linked leucine zipper motif (Zip). We have suggested that the HD-Zip motif could, via dimerization of the leucine zippers, recognize dyad-symmetric DNA sequences. Here we report an analysis of the DNA binding properties of the Athb-1 homeodomain-leucine zipper (HD-Zip-1) domain in vitro. DNA binding analysis performed using random-sequence DNA templates showed that the HD-Zip-1 domain, but not the Athb-1 HD alone, binds to DNA. The HD-Zip-1 domain recognizes a 9 bp dyad-symmetric sequence [CAAT(A/T)ATTG], as determined by selecting high-affinity binding sites from random-sequence DNA. Gel retardation assays demonstrated that the HD-Zip-1 domain binds to DNA as a dimer. Moreover, the analysis of the DNA binding activity of Athb-1 derivatives indicated that a correct spatial relationship between the HD and the Zip is essential for DNA binding. Finally, we determined that the Athb-2 HD-Zip domain recognizes a distinct 9 bp dyad-symmetric sequence [CAAT(G/C)ATTG]. A model of DNA binding by the HD-Zip proteins is proposed.

Amino Acid Sequence↗