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Biomedical subjects

G Cusumano

Publications and source records attributed to G Cusumano.

At least 19 recordsLinked to original sources

FokI polymorphism of the vitamin D receptor gene correlates with parameters of bone mass and turnover in a female population of the Italian island of Lampedusa.

One of the most promising genetic approaches to dissecting a multifactorial disease is represented by genetically isolated population studies. We studied a genetic marker in a cohort of women living on the Mediterranean island of Lampedusa, a geographically isolated population. Lampedusa, located between the African coast and Sicily, consists of a young genetic isolate (<20 generations) with an exponential growth in the last generations. We analyzed the association between the FokI vitamin D receptor (VDR) gene polymorphism, previously proposed as a predictor of bone mass, with parameters of bone mass and turnover in a cohort of pre- and postmenopausal women living on Lampedusa. In 424 women (277 postmenopausal and 147 premenopausal), allelic frequencies were 49% for the F allele and 51% for the f allele. Using analysis of covariance, we found that subjects with ff genotype exhibited a significantly (P < 0.001) lower lumbar spine bone mass, by dual-energy X-ray absorptiometry, and lower values of bone ultrasonographic parameters (speed of sound and broadband ultrasound attenuation) relative to those with Ff and FF genotypes. Conversely, osteocalcin and serum cross-laps were significantly higher in ff and Ff compared to FF genotype. Our data suggest that FokI VDR polymorphism may contribute to the determination of bone mass and turnover in both pre- and postmenopausal women in this geographically isolated population.

Bone Density↗

The association of GRB 060218 with a supernova and the evolution of the shock wave.

Although the link between long gamma-ray bursts (GRBs) and supernovae has been established, hitherto there have been no observations of the beginning of a supernova explosion and its intimate link to a GRB. In particular, we do not know how the jet that defines a gamma-ray burst emerges from the star's surface, nor how a GRB progenitor explodes. Here we report observations of the relatively nearby GRB 060218 (ref. 5) and its connection to supernova SN 2006aj (ref. 6). In addition to the classical non-thermal emission, GRB 060218 shows a thermal component in its X-ray spectrum, which cools and shifts into the optical/ultraviolet band as time passes. We interpret these features as arising from the break-out of a shock wave driven by a mildly relativistic shell into the dense wind surrounding the progenitor. We have caught a supernova in the act of exploding, directly observing the shock break-out, which indicates that the GRB progenitor was a Wolf-Rayet star.

Journal Article↗

Gamma-ray bursts: huge explosion in the early Universe.

Long gamma-ray bursts (GRBs) are bright flashes of high-energy photons that can last for tens of minutes; they are generally associated with galaxies that have a high rate of star formation and probably arise from the collapsing cores of massive stars, which produce highly relativistic jets (collapsar model). Here we describe gamma- and X-ray observations of the most distant GRB ever observed (GRB 050904): its redshift (z) of 6.29 means that this explosion happened 12.8 billion years ago, corresponding to a time when the Universe was just 890 million years old, close to the reionization era. This means that not only did stars form in this short period of time after the Big Bang, but also that enough time had elapsed for them to evolve and collapse into black holes.

Journal Article↗

A short gamma-ray burst apparently associated with an elliptical galaxy at redshift z = 0.225.

Gamma-ray bursts (GRBs) come in two classes: long (> 2 s), soft-spectrum bursts and short, hard events. Most progress has been made on understanding the long GRBs, which are typically observed at high redshift (z approximately 1) and found in subluminous star-forming host galaxies. They are likely to be produced in core-collapse explosions of massive stars. In contrast, no short GRB had been accurately (< 10'') and rapidly (minutes) located. Here we report the detection of the X-ray afterglow from--and the localization of--the short burst GRB 050509B. Its position on the sky is near a luminous, non-star-forming elliptical galaxy at a redshift of 0.225, which is the location one would expect if the origin of this GRB is through the merger of neutron-star or black-hole binaries. The X-ray afterglow was weak and faded below the detection limit within a few hours; no optical afterglow was detected to stringent limits, explaining the past difficulty in localizing short GRBs.

Journal Article↗

An unexpectedly rapid decline in the X-ray afterglow emission of long gamma-ray bursts.

'Long' gamma-ray bursts (GRBs) are commonly accepted to originate in the explosion of particularly massive stars, which give rise to highly relativistic jets. Inhomogeneities in the expanding flow result in internal shock waves that are believed to produce the gamma-rays we see. As the jet travels further outward into the surrounding circumstellar medium, 'external' shocks create the afterglow emission seen in the X-ray, optical and radio bands. Here we report observations of the early phases of the X-ray emission of five GRBs. Their X-ray light curves are characterised by a surprisingly rapid fall-off for the first few hundred seconds, followed by a less rapid decline lasting several hours. This steep decline, together with detailed spectral properties of two particular bursts, shows that violent shock interactions take place in the early jet outflows.

Journal Article↗

Bright x-ray flares in gamma-ray burst afterglows.

Gamma-ray burst (GRB) afterglows have provided important clues to the nature of these massive explosive events, providing direct information on the nearby environment and indirect information on the central engine that powers the burst. We report the discovery of two bright x-ray flares in GRB afterglows, including a giant flare comparable in total energy to the burst itself, each peaking minutes after the burst. These strong, rapid x-ray flares imply that the central engines of the bursts have long periods of activity, with strong internal shocks continuing for hundreds of seconds after the gamma-ray emission has ended.

Journal Article↗

Excitotoxin-induced changes in transglutaminase during differentiation of cerebellar granule cells.

Excitotoxicity induced by NMDA receptor stimulation is able to increase the activity of many enzymes involved in neuronal cell death. Primary cultures of rat cerebellar granule cells were used to elucidate the role of transglutaminase reaction in the excitotoxic cell response, and to evaluate the role of glutamate receptors in cell survival and degeneration. Granule neurons, maintained in vitro for two weeks, were exposed to NMDA at different stages of differentiation. Following NMDA receptor activation, increases in transglutaminase activity were observed in cell cultures. The levels of enzyme activity were higher in cells at 5 days in vitro than in those at 8-9 or 13-14 days in vitro. Moreover, NMDA exposure up-regulated tTG expression in neurons as young as 5 days in vitro. These cultures also exhibited morphological changes with clear apoptotic features. Results obtained demonstrate that susceptibility of granule cells to excitotoxicity depends on the developmental stage of neurons.

Animals↗

Effects of mud-pack treatment on plasma cytokine and soluble adhesion molecule levels in healthy volunteers.

BACKGROUND: The suggested hypothesis of a direct anti-inflammatory property of mud-pack treatment has led us to speculate that its action on the cytokine network might counteract the heat-stress-related effects on platelet and endothelial cell function often reported following hot-spring baths. Therefore, the present study was designed to investigate the effects of a cycle of 12 daily mud-pack treatments on bio-humoral markers of inflammation, as well as on markers of in vivo platelet and/or endothelial cell activation, in plasma samples obtained from healthy volunteers. METHODS: Blood samples were obtained before (T(0)), at the end of the first treatment (T(1)) and after a cycle of 12 daily mud-pack treatments (T(2)). Plasma cytokines (TNF-alpha IL-1beta, and IL-6) and adhesion molecules (sP-selectin, sE-selectin and sVCAM) levels, as well as hematocrit and complete and differential blood cell counts were determined at every time point. RESULTS: Plasma sP-selectin levels were not modified during treatment, as were not sE-selectin or sVCAM. Similarly, IL-1beta and TNF-alpha levels were unchanged through a 12 daily mud-pack treatment. Conversely, plasma IL-6 levels were significantly lowered at the end of a 20-min 47 degrees C mud-pack treatment (p<0.01). CONCLUSIONS: The lack of effects on in vivo platelet and/or endothelial cell activation suggests that hot mud-pack treatment might be used as a relatively safe procedure in patients with atherothrombotic disorders.

Adult↗

Detection of 33.8 Millisecond X-Ray Pulsations in SAX J0635+0533.

We revisited the BeppoSAX observation of SAX J0635+0533, which was suggested as a possible counterpart to the gamma-ray source 2EG J0635+0521. We have discovered a 33.8 ms pulsation from the source and derived an improved position, consistent with the location of the Be star proposed as a binary companion. We interpret the periodicity as the spin period of a neutron star in a binary system with a Be companion.

Journal Article↗

Ureteral anastomosis in the orthotopic ileal neobladder: comparison of 2 techniques.

PURPOSE: The functional results and complications of 2 different ureteroileal anastomoses were evaluated in patients with bladder cancer undergoing radical cystectomy and orthotopic ileal bladder substitution. MATERIALS AND METHODS: Between 1989 and 1995, 102 patients underwent creation of a low pressure neobladder. In the first 50 cases the ureteroileal anastomosis was created with a split-cuff nipple technique as an additional antireflux mechanism. In the next 52 cases the ureteroileal anastomoses were constructed via the direct end-to-side technique counting on the antireflux protection of the afferent tubular limb. RESULTS: Stenosis occurred in 7 of the 100 ureters (6 patients) treated with the split-cuff nipple technique and 7 of 104 treated with a direct end-to-side anastomosis. This complication occurred more commonly in the left ureter (11 of 14 patients). Reflux was noted at cystography in 10 cases with the split-cuff nipple method and 12 with end-to-side anastomoses, and was symptomatic in only 3 patients. Four ureteral strictures were treated successfully with primary open repair. Percutaneous dilation and stenting were performed for 8 ureteral strictures: 2 cases were successful, 3 failed and 3 are unresolved. CONCLUSIONS: We observed no differences between the antireflux split-cuff and end-to-side anastomoses with regard to stricture formation or ureteral reflux. Therefore, we do not believe that there is a need to create antireflux ureteral anastomoses due to the tubular afferent ileal segment and given that the reflux is asymptomatic in most patients. Strictures may be treated with percutaneous balloon dilation and stenting but open repair appeared to be more effective.

Anastomosis, Surgical↗

Local immunotherapy of superficial bladder cancer by intravesical instillation of recombinant interleukin-2.

Local immunotherapy of superficial bladder cancer by endovesical administration of recombinant interleukin-2 (rIL-2) was investigated in a phase I-II study. Twenty-five patients with Ta-T1, N0, M0, G1-G2 transitional cell carcinoma of the bladder received an induction course of rIL-2 (10 daily instillations) with the tumor in place using an interpatient dose escalation scheme from 3 to 18 x 10(6) IU/day. Seven to fourteen days after the end of the induction course, the objective clinical response was evaluated and transurethral resection of the bladder tumor was carried out. Four maintenance courses (10 daily instillations) were started 1 month after surgery and carried out every 4 months at a dose of 6 x 10(6) IU/day in all patients. Follow-up visits were scheduled bimonthly during treatment and then every 6 months. No evidence of laboratory, local or systemic toxicity was observed even at the highest rIL-2 dosages. Induction of a local inflammatory response could be demonstrated at the tumor site after intravesical rIL-2 treatment. The significant reduction in tumor diameters observed in some patients may be interpreted as a sign of the biological activity of this rIL-2 regimen. Further exploratory work is required to evaluate the clinical efficacy of this immunotherapeutic approach.

Administration, Intravesical↗

Colpocystodefecography.

PURPOSE: To assess, in one single procedure, a complete study of the female pelvis, including the Douglas pouch. METHODS: Colpocystodefecography (CCD) combines vaginal opacification, voiding cystography, and defecography. Three hundred examinations are reviewed. RESULTS: Thanks to the simultaneous visualization of the pelvic structures, CCD proved to be more useful than clinical evaluation to diagnose prolapses and particularly Douglas pouch hernias (enteroceles), the clinical diagnosis of which was missed in 93 of 111 cases. Moreover, in addition to morphologic and functional information, CCD brings about a new insight in the study of pelvic organs reciprocal influences, should they be positive (supporting function) or negative (external compression). Finally, significative pelvic surgery and particularly hysterectomy enhances greatly the risk of enteroceles. CONCLUSION: CCD is helpful in the preoperative staging, especially in the selection of the surgical procedure that will least likely predispose to possible late postoperative complications such as vaginal prolapses or enteroceles.

Adult↗

[Nerve-sparing cystectomy and ileal bladder substitution].

Nerve-sparing techniques and bladder substitution following radical cystectomy allow today to obviate functional sequelae once registered in this type of surgery. Intraoperative identification of the pelvic plexus, which provides autonomic innervation to the corpora cavernosa, is necessary to preserve sexual function. Ileal orthotopic bladder substitution with preservation of the distal urethral sphincter assures a micturition per urethram and the urinary continence. The Authors report their experience with the Studer and Zingg procedure (ileal orthotopic bladder reservoir) performed in 26 cases. Results, technique, complications, and long-term evaluation are stressed.

Aged↗

[Value of the measurement of SP1 protein in the early diagnosis of pregnancy induced with Pregnyl].

Successive dilutions of Pregnyl have been submitted to a radioimmunoassay of SP1. We have observed that Pregnyl cross-reacts with SP1. Chromatography of Pregnyl demonstrates that the contaminating substance is different from native SP1. As its concentration is low, it is however not detected in the serum of patients after the administration of exogenous Pregnyl. SP1 measurement can be helpful in detecting early pregnancies after hCG induction of ovulation.

Adult↗

CT diagnosis of Budd-Chiari syndrome.

The computed tomographic (CT) findings in Budd-Chiari syndrome are described. With repeated injections of contrast medium, using an angio-CT technique, the authors consistently obtained a good and homogeneous enhancement of the liver parenchyma and vascular structures. The portal and hepatic veins were routinely seen. In Budd-Chiari syndrome, the authors found patchy enhancement of the involved section of the liver and absence of visualization of the hepatic veins. The latter is considered characteristic of hepatic vein obstruction and should not be misinterpreted as a consequence of neoplastic lesion.

Adult↗