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Biomedical subjects

M Grande

Publications and source records attributed to M Grande.

At least 19 recordsLinked to original sources
PubMed2006

Plasma acceleration above martian magnetic anomalies.

Auroras are caused by accelerated charged particles precipitating along magnetic field lines into a planetary atmosphere, the auroral brightness being roughly proportional to the precipitating particle energy flux. The Analyzer of Space Plasma and Energetic Atoms experiment on the Mars Express spacecraft has made a detailed study of acceleration processes on the nightside of Mars. We observed accelerated electrons and ions in the deep nightside high-altitude region of Mars that map geographically to interface/cleft regions associated with martian crustal magnetization regions. By integrating electron and ion acceleration energy down to the upper atmosphere, we saw energy fluxes in the range of 1 to 50 milliwatts per square meter per second. These conditions are similar to those producing bright discrete auroras above Earth. Discrete auroras at Mars are therefore expected to be associated with plasma acceleration in diverging magnetic flux tubes above crustal magnetization regions, the auroras being distributed geographically in a complex pattern by the many multipole magnetic field lines extending into space.

Journal Article↗
PubMed2006

Can Phyllanthus niruri affect the efficacy of extracorporeal shock wave lithotripsy for renal stones? A randomized, prospective, long-term study.

PURPOSE: Phyllanthus niruri is a plant used in Brazilian folk medicine for the treatment of urolithiasis. We assessed the efficacy of P. niruri after extracorporeal shock wave lithotripsy for renal stones. MATERIALS AND METHODS: We prospectively evaluated 150 patients with renal stones that were as large as 25 mm and composed of calcium oxalate. All patients received 1 to 3 extracorporeal shock wave lithotripsy sessions by Dornier Lithotriptor S. After treatment 78 of 150 patients (52%) underwent therapy with Uriston, a P. niruri extract (2 gm daily) for at least 3 months (group 1). Otherwise 72 of 150 patients (48%) were used as a control group (group 2). No significant difference in stone size between the 2 groups was found. Stone clearance was assessed after 30, 60, 90 and 180 days by abdominal x-ray and ultrasound scan. RESULTS: Stone-free rate (stone-free defined as the absence of any stone or residual fragments less than 3 mm) was 93.5% in group 1 and 83.3% in group 2 (p = 0.48) at the end point of the followup (180 days). For lower caliceal stones (56 patients) the stone-free rate was 93.7% in the treatment group and 70.8% in the control group (p = 0.01). Re-treatment need for group 1 was 39.7% and for group 2 it was 43.3% (p = 0.2). No side effects were recorded with extracorporeal shock wave lithotripsy or P. niruri therapy. CONCLUSIONS: Regular self-administration of P. niruri after extracorporeal shock wave lithotripsy for renal stones results in an increased stone-free rate that appears statistically significant for lower caliceal location. Its efficacy and the absolute lack of side effects make this therapy suitable to improve overall outcomes after extracorporeal shock wave lithotripsy for lower pole stones.

Adult↗
PubMed2006

Medical therapy of urolithiasis.

Nephrolithiasis treatment has become easier and less invasive with the development of extracorporeal shockwave lithotripsy (SWL) and endourologic techniques. However, medical therapy represents a well-established and complementary approach that can improve the efficacy of SWL and endourology. During recent decades, pharmacologic intervention has become more effective in stone disease: drugs can control the pain of renal colic, interfere at various levels in lithogenesis, and contribute to the expulsion of stones. It is well known that lithogenesis is a multifactorial process influenced by environmental-nutritional factors (low urinary volume, diet rich in animal protein, etc) and metabolic alterations; i.e., hypercalciuria, hyperuricosuria, and deficiency of stone-inhibiting factors (citrate, magnesium, glycosaminoglycans [GAGs]). Specific drugs such as citrate, allopurinol, and thiazide represent highly effective treatments for the promoting factors. Furthermore, recent findings suggest an interesting role for a phytotherapeutic agent, Phillantus niruri, and its inhibitory action on calcium oxalate crystallization related to the higher incorporation of GAGs into the calculi. Another step forward in medical management of stone disease is expulsive therapy. Many studies have proven the efficacy of medical expulsive therapy with nifedipine and alpha-blockers: their specific action on ureteral smooth muscle in association with anti-edema drugs accounts for their efficacy in expelling ureteral stones. In this paper, we provide an update on the medical treatment of stone disease, focusing our attention on what is known and what is new in renal colic and litholithic and expulsive medical therapy.

Colic↗
PubMed2005

Laparoscopic telementored adrenalectomy: the Italian experience.

BACKGROUND: Laparoscopy is widely accepted as the gold standard for adrenalectomy. Telementoring has been developed to reduce the complications associated with surgeon inexperience. We report our preliminary experience with laparoscopic telementored adrenalectomy. METHODS: From July 2002 to May 2003, eight laparoscopic telementored adrenalectomies were performed between two separate operating sites 430 km apart. Six of these procedures were monolateral laparoscopic adrenalectomies, and one was bilateral. All cases were performed by an expert open surgeon who was skilled in laparoscopic procedure but who had no experience in laparascopic adrenalectomy RESULTS: All the procedures were successfully performed in a telementored fashion. The mean operative times, blood loss, and postoperative morbidity results were comparable to those for standard laparoscopic adrenalectomies reported in the literature. CONCLUSIONS: This preliminary experience has demonstrated the feasibility of national telementoring. It is a viable method that can potentially add to surgical education and decrease the likelihood of complications due to inexperience with new techniques.

Adolescent↗
PubMed2005

Composition and dynamics of plasma in Saturn's magnetosphere.

During Cassini's initial orbit, we observed a dynamic magnetosphere composed primarily of a complex mixture of water-derived atomic and molecular ions. We have identified four distinct regions characterized by differences in both bulk plasma properties and ion composition. Protons are the dominant species outside about 9 RS (where RS is the radial distance from the center of Saturn), whereas inside, the plasma consists primarily of a corotating comet-like mix of water-derived ions with approximately 3% N+. Over the A and B rings, we found an ionosphere in which O2+ and O+ are dominant, which suggests the possible existence of a layer of O2 gas similar to the atmospheres of Europa and Ganymede.

Atmosphere↗
PubMed2005

Laparoscopic adrenal surgery: new frontiers.

After about 10 years of experience, laparoscopic adrenalectomy has become the gold standard for the treatment of adrenal lesions. Here, we describe the presenting features, imaging methods, and current surgical approaches to diseases of the adrenal gland. There is general agreement on the suitability of the laparoscopic approach for benign adrenal lesions, but controversy exists about using laparoscopy for suspected adrenal malignancy, metastasis, and partial adrenalectomy. This article reviews the literature on laparoscopic adrenalectomy. In particular, we focus our attention on the new surgical approaches to the gland. We evaluate the indications, operative techniques, and tools for partial adrenalectomy, and we discuss new surgical strategies such as cryosurgery and radiofrequency ablation.

Adrenal Cortex Neoplasms↗
PubMed2004

Solar wind-induced atmospheric erosion at Mars: first results from ASPERA-3 on Mars Express.

The Analyzer of Space Plasma and Energetic Atoms (ASPERA) on board the Mars Express spacecraft found that solar wind plasma and accelerated ionospheric ions may be observed all the way down to the Mars Express pericenter of 270 kilometers above the dayside planetary surface. This is very deep in the ionosphere, implying direct exposure of the martian topside atmosphere to solar wind plasma forcing. The low-altitude penetration of solar wind plasma and the energization of ionospheric plasma may be due to solar wind irregularities or perturbations, to magnetic anomalies at Mars, or both.

Journal Article↗
PubMed2002

Different Kv2.1/Kv9.3 heteromer expression during brain and lung post-natal development in the rat.

The Kv2.1/Kv9.3 heteromer generates an O2 sensitive potassium channel and induces a slow deactivation that has important consequences for brain and lung physiology. We examined the developmental regulation of Kv2.1 and Kv9.3 mRNAs in brain and lung. Both genes followed parallel expression patterns in brain, increasing progressively through post-natal life. In lung, however, the expression of the two genes followed opposite trends: Kv2.1 transcripts decreased, while Kv9.3 mRNA increased. The Kv9.3/Kv2.1 ratio shows that while in brain the expression of both genes followed a similar pattern, the relative abundance of Kv9.3 increased steadily through post-natal life in lung. Furthermore, there is selective regulation of gene expression during the suckling-weaning transition. Our results suggest that different Kv9.3/Kv2.1 ratios could have physiological implications in both organs during post-natal development, and that diet composition and selective tissue-specific insulin regulation modulate the expression of Kv2.1 and Kv9.3.

Animals↗
PubMed2002

One-step reverse transcription polymerase chain reaction for semiquantitative analysis of mRNA expression.

Analysis of mRNA expression is one of the main targets of scientific research. However, its quantification can be difficult, especially when dealing with low-expression mRNAs (ionic channels, carriers, receptors, etc.) or when only small samples are available (human biopsies). Here we suggest an easy, rapid and reliable method to assess semiquantitative changes in mRNA that combines several technical improvements: i) one-step reverse transcription polymerase chain reaction (RT-PCR) from total RNA; ii) addition of ethidium bromide to the gel, which provides a more homogeneous binding to DNA; iii) direct capture of the gel image using a charged-coupled device camera and then saving the image on computer before quantification, which increases resolution and thus improves and shortens the analysis; and iv) the use of 18S rRNA as a control, which is especially useful when samples from activation, differentiation and proliferation models are used. The technique was validated by checking the system conditions of image capturing and quantification. This was corroborated by a study of Kvl.3 ion channel expression in the brain. In these conditions, the wide range of PCR cycles and total RNA allows us to correlate relative gene expression and direct input of the target gene.

Animals↗
PubMed2001

Systemic acute-phase response after laparoscopic and open cholecystectomy.

BACKGROUND: Cytokines are the main mediators of inflammation and the response to trauma. The purpose of this study was to compare variations in cytokine levels following laparoscopic cholecystectomy (LC) and mini-laparotomy cholecystectomy (OC), since these two types of operations were considered to be a unique model for examining the role of local tissue injury in postoperative inflammatory reactions. METHODS: A total of 40 patients were studied. Eighteen of them underwent LC; the remaining 22 were operated on using the open technique. Systemic concentrations of interleukin-6 (IL-6), interleukin-1 (IL-1), tumor necrosis factor (TNF), and C-reactive protein (CRP) were measured before and after the operation. In addition, we compared pre- and postoperative white blood cell (WBC) counts, postoperative body temperature, and length of postoperative hospitalization. RESULTS: There was no difference between the two groups in IL-1 and TNF response. The rise in plasma IL-6 levels (18.86 +/- 9.61 vs 5.00 +/- 0.0 pg/ml, p < 0.0001) and CRP (8.40 +/- 5.81 vs 1.43 +/- 1.30 mg/dl, p < 0.001) were more marked after open cholecystectomy than after the laparoscopic procedure. There was no correlation between serum CRP concentrations and the other postoperative parameters. CONCLUSION: The magnitude of the acute-phase response was less pronounced following laparoscopic cholecystectomy, consistent with a reduction in tissue trauma.

Acute-Phase Reaction↗
PubMed2001

Abdominal aortic aneurysm in normotensive patients: association with angiotensin-converting enzyme gene polymorphism.

OBJECTIVE AND DESIGN: to assess if deletion of the angiotensin-converting enzyme (ACE) gene is a risk factor for abdominal aortic aneurysms (AAAs) in normotensive patients. MATERIALS AND METHODS: ACE gene polymorphism was examined by polymerase chain reaction in 124 subjects with AAA and in 112 control subjects. AAA normotensive patients (group A, n=56) were compared to normotensive control subjects (group B, n =112) and to AAA hypertensive patients (group C, n =68). All subjects enrolled in this study were Caucasian and from central and southern Italy. RESULTS: the distribution of ACE genotypes was: normotensive patients with AAAs (group A): 3 II, 14 ID, 39 DD; normotensive control subjects (group B): 36 II, 48 ID, 28 DD; hypertensive patients with AAAs (group C): 14 II, 32 ID, 22 DD. The DD genotype was more common in group A than in control groups (A vs B p<0.001; A vs C p <0.001). The ID genotype was more common in group A as well (A vs B p <0.05; A vs C p <0.005). CONCLUSIONS: our data suggest a role for ACE I/D gene polymorphism in the pathogenesis of AAA in normotensive patients.

Aged↗
PubMed2000

Tissue concentrations of tissue polypeptide antigen (TPA) and prostatic specific antigen (PSA) in 42 patients with prostatic carcinoma.

BACKGROUND: Following development of methods to quantitate biochemical markers in aspiration biopsies we showed that tissue concentration of prostate specific antigen (T-PSA) decreased with increasing malignancy while serum PSA increased. We also found that T-PSA predicts the clinical outcome better than earlier used prognostic markers. METHODS: In order to further study biochemical markers in prostatic cancer a membrane protein, tissue polypeptide antigen (TPA), which is a complex of polypeptide fragments of cytokeratins 8, 18, and 19, was quantitated in 42 patients with newly diagnosed carcinoma of the prostate. The samples had previously been analyzed for T-PSA. RESULTS: Correlation to TGM classification showed that higher malignancy is correlated to lower tissue TPA values. There is a significant positive correlation (r(s) = 0.49, P < 0.01) between T-TPA and T-PSA. Pretreatment values of T-PSA, but not T-TPA, had association to time to progression or time to death. CONCLUSIONS: Increasing prostatic malignancy is correlated to decreasing values of T-TPA. This indicates that the concentrations of membrane and secretory proteins are changed in the same direction in tissue during cancer development. Tissue TPA seem to have no prognostic value in endocrine treatment of prostatic carcinoma.

Aged↗
PubMed2000

Estrogens increase the endothelial nitric oxide synthase (ecNOS) mRNA level in LNCaP human prostate carcinoma cells.

BACKGROUND: The endothelial cell-specific form of nitric oxide synthases (ecNOS) may play an important role in vascular development, maintenance of vascular tone, and tumor growth in human prostate cancer. Estrogens have been shown to upregulate ecNOS expression in different human cell culture systems. Estrone sulfate (E1S) is the most abundant circulating estrogen, and may serve as a prehormone for the terminal biologically active estrogen estradiol-17beta (E2) in men. METHODS: The effects of E1S and E2 on mRNA expression of ecNOS were studied in the androgen-sensitive LNCaP-FGC cell line and its androgen-resistant derivative, LNCaP-r. The cells were grown in steroid-depleted medium and incubated for 2-4 or 48 hr with 0-100 nM of E1S and E2, respectively. ecNOS mRNA levels were determined using RT-PCR and are expressed as arbitrary units after correction for control HGPRT gene mRNA levels. RESULTS: Treatment for 48 hr with 10 and 100 nM E1S significantly (P<0.05) increased ecNOS mRNA levels in LNCaP-FGC cells. Significantly higher (P<0.05) ecNOS mRNA levels also were found in LNCaP-FGC cells treated with E2 for 2-4 hr, irrespective of E2 concentration. The level of ecNOS mRNA was significantly lower (P<0.05) in untreated LNCaP-r than in LNCaP-FGC. LNCaP-r cells incubated with 100 nM E2 for 48 hr had a significantly higher (P<0.05) level of ecNOS mRNA than control LNCaP-r cells. CONCLUSIONS: The results indicate that ecNOS mRNA expression in LNCaP-FGC can be induced by E2, but also by its prehormone E1S, probably after conversion to E2. However, the different stimulation patterns observed for E2 and E1S in LNCaP-FGC and LNCaP-r cells also could indicate stimulatory as well as inhibitory effects of estrogens in this model system, and this could depend on time of exposure and the concentration of active estrogen.

Endothelium↗
PubMed2000

Coumarins from Ferulago capillaris and F. brachyloba.

Four new coumarins, (+)-senecioylprangol, (-)-3'-senecioyloxymarmesin, (+)-3'-hydroxyprantschimgin and (+)-2"-senecioyloxymarmesin, besides 12 known coumarins have been isolated from two Ferulago species. Their structures have been established by spectroscopic methods and partial synthesis. New synthetic 3'-oxocoumarins are also described. There is a remarkable difference in the contents of the most abundant coumarins found in the roots of both species: osthol and aurapten are specific to F. capillaris and F. brachyloba, respectively.

Apiaceae↗
PubMed2000

Prognostic significance of tissue prostate-specific antigen in endocrine-treated prostate carcinomas.

Fine-needle aspiration biopsy is a minimally invasive technique for obtaining sample material suitable not only for cytological grading but also for flow cytometry and for biochemical analyses. The prognostic value of tissue prostate-specific antigen (T-PSA) from fine-needle aspiration biopsies was compared with serum total and free prostate-specific antigen, the ratio of free:total serum prostate-specific antigen, tumor stage, cytological grade, and DNA ploidy in 179 patients with stage T2-T4 prostate cancer (CAP). The patients, who were free from bone metastases at the time of diagnosis, were treated by either orchidectomy or medical castration with GnRH analogues or high-dose parenteral depot estrogens. They were followed for at least for 71 months or until death, and the different variables were correlated to time to progression and time to death from CAP. Using Cox univariate analysis, T-PSA was shown to be the most important factor in predicting time to progression and time to death. When the patients were divided into three groups with respect to T-PSA, 56 of 60 (93%) of the patients with low T-PSA levels developed progressive disease, and 52 of 60 (87%) died of CAP. For patients with intermediate T-PSA levels, the corresponding figures were 9 of 60 (15%) and 6 of 60 (10%). None of the 59 patients with high T-PSA values developed progressive disease. Similar but less pronounced relationships were found between tumor progress and CAP-specific death on the one hand and clinical stage, cytological grade, and DNA ploidy on the other. In a Cox multivariate stepwise analysis, T-PSA was the only important factor for time to progression and death. This was also true for the subgroup of patients with stages T2 and T3 disease only. The study shows that T-PSA is superior to other hitherto routinely used markers for the prediction of outcome of hormone-treated patients with newly diagnosed CAP.

Aged↗