Biomedical subjects

A Carpi

Publications and source records attributed to A Carpi.

At least 55 records · Page 3Linked to original sources

PubMed2004

Osteoporosis and biomaterial osteointegration.

Biomaterial osteointegration depends not only on the properties of the implanted material but also on the characteristics and regenerative capability of the host bone. For this reason, researchers involved in biomaterial evaluation now place great importance on the various pathologies often present in orthopaedic patients which can negatively affect the success of surgical implants. Osteoporosis is undoubtedly one of the most frequently encountered of such diseases. Models reproducing the osteoporotic condition can be useful to understand the influence of the pathology on cell behaviour, bone regeneration and osteointegration processes, thus increasing our basic knowledge and allowing the development of surgical techniques and implant biomaterials more suitable for use in the surgical treatment of fractures in osteoporotic patients. The present paper is a literature review and, after a short description of how the presence of osteoporosis could influence bone regenerative processes, the results of the main studies on biomaterial biocompatibility and osteointegration both in vitro and in vivo in the presence of osteoporotic condition are reported. Both cell cultures and animal models are able to demonstrate the different response of bone to biomaterials by comparing healthy and pathological conditions. The use of pathological bone-derived cells and pathological animals is therefore recommended to test candidate orthopaedic materials.

Animals↗

PubMed2004

Different diagnostic techniques for the assessment of cortical bone on osteoporotic animals.

The aim of this study was to assess the capability of ultrasonography and densitometry to predict the mechanical competence of cortical bone in healthy and osteopenic rats, respectively. Thirty 10-month-old Sprague-Dawley retired breeder female rats were used and randomized into three groups of 10 animals each. A group underwent bilateral ovariectomy by dorsal approach (Ovx), another group underwent a simulated ovariectomy (Sham-Ovx), and the last group served as a sham-aged control group (Control). Sixteen weeks after surgery, the animals were euthanized and the femurs of each rat excised for ultrasonographic and densitometric measurements, and mechanical analyses. The Ovx Group had a significantly decreased amplitude dependent speed of sound (AD-SoS-about 7-8%) when compared to the other groups (p<0.0005). For Ovx animals compared with Sham-Ovx and Control rats, significant decreases in densitometric data were observed (6-13%), as well as significant decreases in femoral Max. Load (about 18%) and flexural rigidity (about 30%). The best correlation (R2=0.55, p<0.0005) found was between SoS and femoral shaft bone mineral density (SBMD). The regression coefficient R2 increased when power-law fits were used, particularly from 0.34 (p<0.001) to 0.36 (p<0.0005) in the correlation between SoS and Max. Load and from 0.21 (p<0.05) to 0.25 (p<0.01) in the correlation between SBMD and Max. Load. The ability of QUS or DXA to accurately predict the actual mechanical characteristics of bone, and in particular bone elasticity, remained relatively poor and the improvement of the power-law model did not describe exhaustively the relationships between the variables tested. The DXA and QUS capability to discriminate between ovariectomized and non-ovariectomized rats did not improve when tested together.

Absorptiometry, Photon↗

PubMed2004

Spectral analysis of skin laser Doppler blood perfusion signal during cutaneous hyperemia in response to acetylcholine iontophoresis and ischemia in normal subjects.

Spectral analysis of skin laser Doppler (LD) signal was performed using Fourier transformation in twelve healthy subjects in order to compare post-ischemic hyperemia and acetylcholine (ACh) iontophoresis tests for the exploration of cutaneous microcirculatory endothelial function. Within the frequency range studied of 0.009-1.6 Hz, five different frequency intervals were considered, arising from local (endothelial and myogenic) and central (neural, respiratory and cardiac) regulatory mechanisms. The power density (PD) for each of the five frequency intervals considered was measured in perfusion units (PU)/Hz, in each subject, before and in response to ischemia and to ACh iontophoresis, using a dedicated software. The relative contribution of each frequency interval was calculated as per cent rate between each PD and the sum of the PD of the five frequency interval considered. PD of LD signals in response to ischemia and Ach iontophoresis significantly increased for all the five frequency intervals considered. A significant increase (from 25.0+/-6.3 to 48.3+/-17.8; p<0.01) in the relative contribution of 0.009-0.02 frequency interval, referred to endothelium activity, was observed only in response to ACh iontophoresis. No significant increase in the relative power contribution was observed in response to ischemia for any of the five frequency intervals considered. These data suggest that ACh iontophoresis test is more adequate than post-ischemic hyperemia test in exploring the skin microcirculatory endothelial function in normal subjects.

Acetylcholine↗

PubMed2003

Advanced breast cancer: an update and controversies on diagnosis and therapy.

This review on advanced breast cancer considered important differences in the actual definition of this condition. Advanced breast cancer includes locally advanced, locoregionally recurrent and metastatic disease, which have different diagnosis, prognosis and therapy; their actual definitions are relatively uncertain. Differently from the common opinion that metastatic breast cancer (MBC) is a very severe incurable disease, recently it has been reported that a small but not irrelevant fraction of MBC patients can be cured or remain in long-term survival with complete remission. The type of metastases of the population studied in these reports was analysed and the authors hypothesised that the particularly high DFS reported mainly was attributable to the high proportion of patients with locoregional metastases only. Furthermore, the options and associations of the drug therapy available for treatment of advanced breast cancer have been reviewed.

Breast Neoplasms↗

PubMed2003

Comparative interspecies investigation on osteoblast cultures: data on cell viability and synthetic activity.

The aim of the present study was to evaluate and compare the most common parameters that characterize the expression of primary osteoblast cultures from different origin (human, rat, sheep), and of the human osteosarcoma cell line MG-63 before and after stimulation with vitamin 1,25(OH)(2)D(3). Cell viability was quite similar for primary osteoblast cultures (MTT: 1.64-2.11 OD); a significant (P < 0.005) difference was found between sheep osteoblasts and MG-63 (DeltaMTT: 0.52 +/- 0.20 OD). Osteocalcin synthesis ranged from 15.18 to 27.00 pg/ml in primary osteoblast cultures, while it was significantly (P < 0.01) lower in MG-63 (OC: 6.67 +/- 0.52 pg/ml) when compared with primary human osteoblasts. Alkaline phosphatase, C-terminal procollagen type I, and interleukin-6 were significantly (P < 0.005) lower in rat osteoblasts when compared with primary human osteoblasts, and similarly transforming growth factor-beta1 was significantly (P < 0.05) lower in rat and sheep osteoblasts when compared with primary human osteoblasts and MG-63. Nitric oxide synthesis did not show any significant difference either before or after vitamin 1,25(OH)(2)D(3) stimulation. In conclusion, the current findings confirm the presence of interspecies differences between the selected osteoblast lineages before and after stimulation with vitamin 1,25(OH)(2)D(3). Above all, the culture of sheep osteoblasts was seen to behave more similarly to that of primary human cells, mainly in terms of cell viability, osteocalcin, interleukin-6 and transforming growth factor-beta1 production.

Animals↗

PubMed2003

Cytokine secretion in nasal mucus of normal subjects and patients with allergic rhinitis.

Allergic rhinitis is regulated by the local production and release of several cytokines. The levels of Th2 cytokines IL-4, IL-6, IL-10 and the Th1 cytokine IFN-gamma were studied in nasal mucus from 30 subjects with allergic rhinitis and 45 non-atopic healthy controls. In this study a sampling technique for collecting nasal mucus, well tolerated by the subjects and with a minimal stimulation of the mucosa, was performed. The cytokine concentrations in nasal mucus samples were detected and quantitated by a new paramagnetic particle-based immunofluorescent assay system more sensitive than the conventional ELISA techniques. The new technique showed reliable values of the measured parameters. The nasal mucus from allergic patients contained significantly higher concentrations of IL-4 (25.5 +/- 3.6 pg/ml; P < 0.001) and IL-10 (1300 +/- 190 pg/ml; P < 0.05) compared to the nasal mucus from control subjects (15.2 +/- 2.3 and 532 +/- 28 pg/ml, respectively, for IL-4 and IL-10). No significant modification in IFN-gamma levels of allergic patients was found when compared to control group (respectively, 19.9 +/- 3.3 vs. 25.7 +/- 5.1 pg/ml; P > 0.05). Moreover, the allergic patients showed lower levels of IL-6 concentrations in the nasal mucus compared to control subjects (64.8 +/- 9.1 vs. 129.0 +/- 18.1 pg/ml; P = 0.0099). These data can be interpreted by the hypothesis that in response to environmental allergens there is a preferential Th2 polarity by activated CD4+ T cells and that the cytokines IL-6 and IL-10 have, respectively, an important anti-inflammatory and counterregulatory action in the pathogenesis of allergic rhinitis.

Adolescent↗

PubMed2002

Phalangeal ultrasonography in forearm fracture discrimination.

Over the last decade, the use of ultrasounds has been developed into an effective tool for investigating bone tissue and predicting the risk of fracture in osteoporosis. Studies have focused on hip and vertebral fractures while no information is available on the use of phalangeal ultrasonography to identify patients with forearm fractures. Thus, the current authors decided to compare 50 postmenopausal women with low energy forearm fractures (Fractured Group) with a control age-matched group of 94 women (Control Group). Measurements were taken at the distal metaphysis of the proximal phalanxes of the hand of the non-fractured arm using the DBM Sonic Bone Profiler. The reproducibility of the method was assessed by amplitude-dependent speed of sound (AD-SoS) CV% = 0.64 and by Ultrasound Bone Profiler Index (UBPI) CV% = 2.38. In the Control Group, the AD-SoS and UBPI mean values and standard deviations were significantly higher compared to the group with fractures (P < 0.0005). The receiver operating characteristic (ROC) curves were calculated and the areas under the curve (AUC) were 0.78 +/- 0.04 for AD-SoS and 0.77 +/- 0.05 for UBPI, respectively. Logistic regression analysis adjusted to age revealed that both AD-SoS (78.2%, ORAD-SoS = 12.03, P < 0.0005) and UBPI (76.0%, ORAD-SoS = 7.39, P < 0.0005) parameters discriminated correctly between fractured and non-fractured control women whereas the association of both parameters could not allow better discrimination. The present results showed that ultrasound investigation at the phalanxes is reproducible and efficiently discriminates between subjects with forearm fractures and those in the control subjects.

Aged↗

PubMed2002

Atherosclerosis and cancer: common pathways on the vascular endothelium.

This article reviews experimental and clinical data on atherosclerosis and cancer showing common pathogenic mechanisms. It is suggested that common pathways follow dysfunction of the vascular endothelium. The activation of the haemostatic system and the overexpression of cytokines and adhesion molecules by the endothelial cells represent important features of this dysfunction. These mechanisms can be responsible for progression of both diseases and explain the higher incidence of thromboembolic events in cancer patients, the occurrence of similar laboratory findings and the effect of many drugs on the course of the two diseases. Our article confirms that atherosclerosis and cancer share common mechanisms, and we hope it will stimulate further clinical trials on the use of drugs active on the haemostatic system in cancer patients.

Animals↗

PubMed2002

Long-term monitoring of cell-mediated immunity in disease-free breast cancer patients: a preliminary retrospective study.

In 102 N- and 44 N+ disease-free breast cancer patients, lymphocytic populations and skin reaction of delayed hypersensitivity (SRDH) were monitored up to 266 months after mastectomy to find out whether they were similar or different from control values. In two selected groups of 34 N- and 11 N+ breast cancer patients, the whole 10 year follow-up was divided into three subintervals, each of them lasting 40 months and the time course of lymphocytic populations was evaluated. In the 102 N- patients, mean CD4+, CD8+, CD3+ values were lower (P < 0.01, P < 0.001, P < 0.01, respectively) while CD4+/CD8+ ratio was higher (P < 0.05) than in controls. Fifteen N- breast cancer patients (16%) were anergic compared to 30(32%) of controls (P < 0.05). In the 34 selected N- breast cancer patients soon after mastectomy the mean value of CD4+, CD8+, CD3+ T subpopulations was lower (P < 0.01, P < 0.001, P < 0.01, respectively) than in controls. Successively their mean value increased so that in the last subinterval they were not or were only slightly lower (P n.s., P < 0.05, P < 0.05, respectively) than in controls. In the 44 N+ patients, mean CD4+, CD8+, CD3+ values were lower (P < 0.001, v < 0.05, P < 0.01, respectively) and CD19+ lymphocytes higher (P < 0.001) than in controls. Five N+ breast cancer patients (13%) were anergic compared to 32% of controls (P < 0.05). In the 11 selected N+ breast cancer patients soon after mastectomy, the mean value of CD4+, CD8+ T subpopulations and CD16+56+ cells was significantly lower (P < 0.001, P < 0.001, P < 0.01, respectively) than in controls. Successively their mean value constantly increased so that in the last subinterval, no or slight (P n.s., P < 0.05, P n.s., respectively) significant difference compared to controls occurred. The mean CD4+/CD8+ ratio value of N- patients was significantly higher than in controls. However in the last subinterval, the significance was lower than in the first one (P < 0.05 and P < 0.01, respectively). In the N+ patients, the mean value of CD4+/CD8+ ratio was constant, although not significantly, lower than in controls; however it progressively increased from the first to the last subinterval. Therefore the significance of the difference of the mean CD4+/CD8+ ratio between N- and N+ patients strongly decreased from the first to the last subinterval (P < 0.001 and P < 0.05, respectively). These data indicate that in breast cancer patients, following mastectomy, a significant activation of memory and CD4+ T cells and long-term decrease of the circulating immunocompetent CD4+, CD8+ and CD16+56+ cells occurs. The prolonged disease-free interval observed in the 34 N- and 11 N+ breast cancer patients can be correlated with the restoration of the normal state of cell-mediated immunity.

Adult↗

PubMed2002

L-arginine and L-lysine stimulation on cultured human osteoblasts.

Essential amino acids, such as L-Arginine (Arg) and L-Lysine (Lys), are involved in bone metabolism and growth. Our previous studies analyzed the effect of these amino acids on rat osteoblast cultures and in experimental animals. In this study, we evaluated the effect of L-Arg and L-Lys on cultured human osteoblasts. Primary human osteoblast cultures were divided into four groups: the Arg Group received 0.625 mg/ml per day of Arg, the Lys Group 0.587 mg/ml per day of Lys, the Arg-Lys Group received both amino acids, whereas the Control Group was sham-treated. After 7 days, the following parameters were tested in all groups: alkaline phosphatase (ALP), nitric oxide (NO), calcium (Ca), phosphorus (P), osteocalcin (OC), type I collagen (PICP), interleukin-6 (IL-6), transforming growth factor-beta 1 (TGF-beta 1) on culture supernatant, platelet derived growth factor (PDGF), insulin-like growth factor-I (IGF-I), and MTT proliferation test on cells. Arg administration significantly increased ALP, NO, PICP and IGF-I production and reduced the level of IL-6. Lys administration over the same time interval mainly affected cell proliferation, as evidenced by the MTT test and immunostaining for PDGF. The same positive effects evidenced by the single administrations of the two amino acids resulted from their simultaneous administration. However, synergism could be demonstrated only for the decrease in the level of IL-6. Arg and Lys show a positive effect on human osteoblasts, which is related partly to the production of those factors required for matrix synthesis, and partly to the direct or mediated activation of cell proliferation.

Arginine↗

PubMed2001

Gaseous elemental mercury as an indoor air pollutant.

Mercury is not commonly considered a household air pollutant; however, a number of potential sources of the metal exist in residential settings. Eleven of 12 indoor sites sampled in this study showed levels of airborne mercury that were significantly elevated over outdoor concentrations (range 6.5-523 ng m(-3)). In addition, this and other published research suggest that up to 10% of households may have levels of airborne mercury above the U.S. EPA reference concentration (300 ng m(-3)) due to historic accidents with mercury containing devices. Exposure to mercury via indoor air is seen as second only to fish consumption as a source of mercury in the general population. Large seasonal changes in indoor mercury levels were identified in this study suggesting that short-term monitoring of mercury-contaminated sites is not sufficient to adequately assess the potential health risks and effectiveness of remediation strategies.

Air Pollutants↗

PubMed2001

Laser biostimulation of cartilage: in vitro evaluation.

An in vitro study was performed to evaluate the laser biostimulation effect on cartilage using a new gallium-aluminium-arsenic diode laser. Chondrocyte cultures were derived from rabbit and human cartilage. These cells were exposed to laser treatment for 5 days, using the following parameters: 300 joules, 1 watt, 100 (treatment A) or 300 (treatment B) hertz, pulsating emission for 10 minutes, under a sterile laminar flow. Control cultures (no treatment) received the same treatment with the laser device off. Cell viability was measured by MTT assay at the end of the laser treatment and then after 5 days. Neither rabbit nor human cultured chondrocytes showed any damage under a light microscope and immunostaining control following laser treatment. The MTT test results indicated a positive biostimulation effect on cell proliferation with respect to the control group. The increase in viability of irradiated chondrocytes was maintained for five days following the end of the laser treatment. The results obtained with the Ga-Al-As diode laser using the above tested parameters for in vitro biostimulation of cartilage tissues provide a basis for a rational approach to the experimental and clinical use of this device.

Analysis of Variance↗

PubMed2001

Effect of L-lysine and L-arginine on primary osteoblast cultures from normal and osteopenic rats.

A therapeutic role of amino acids L-lysine (Lys) and L-arginine (Arg) in osteoporosis and fracture healing was demonstrated previously by in vivo studies. In the present study, primary cultures of osteoblasts were used to investigate the effect of amino acids on gene expression (alkaline phosphatase activity, ALP; osteocalcin, OC; type I collagen), nitric oxide production (NO) and proliferation (MTT) of cells. Cells were isolated from the distal femurs of normal and osteopenic rats. Normal and osteopenic bone-derived cells were divided into four groups: control, Lys (0.587 mg/mL/d), Arg (0.625 mg/mL/d), and Lys + Arg (0.587 + 0.625 mg/mL/d). No evidence of differences between normal and osteopenic bone-derived cultures in basal conditions was observed. A significant (P = 0.002) increase of 10.4% in NO production was observed in normal bone-derived osteoblasts treated with Lys + Arg when compared to the control group at 7 days. At the same time, normal bone-derived osteoblasts treated with Arg and Lys + Arg showed significant increases in type I collagen synthesis of 25.3% and 28.4%, respectively, when compared to the control group. Osteopenic bone-derived osteoblasts showed significant (P = 0.002) increases of 27.6% in MTT and 28.7% in cell count at 48 hours when treated with Lys + Arg in comparison with the control group. At 7 days, NO production and type I collagen synthesis increased significantly (P< 0.005) both in osteopenic bone-derived osteoblasts treated with Arg (NO: 18.5%; type I collagen: 34.4%) and Lys + Arg (NO: 23.7%; type I collagen: 20.9%) compared to the control group. Finally, a significant (P = 0.025) decrease of 5.8% in OC level was observed in osteopenic bone-derived osteoblasts treated with Arg. Results suggest that the potential therapeutic effect of Lys and Arg on bone could be related, at least in part, to an improvement of NO production and type I collagen synthesis by osteoblasts both in normal and in osteopenic bone. In osteopenic bone-derived osteoblasts this synthetic phase is preceded by an initial increase of cell proliferation.

Animals↗

PubMed2001

Comparison of calcitonin, alendronate and fluorophosphate effects on ovariectomized rat bone.

The effects of calcitonin, alendronate and fluorophosphate preventive treatment on ovariectomized rat femur were studied by comparing densitometric, mechanical, mineralogical and histomorphometric data. Sixty retired breeder female Sprague-Dawley rats, aged 10 months, were randomly divided into six groups. A group (baseline) was euthanized at the beginning of the study as a baseline group; four groups were ovariectomized and one was sham-operated (sham) and considered as a sham-aged group. A group of ovariectomized rats was used as a sham-therapy control (OVX) and received only deionized drinking water, while the other three received: a) salmon calcitonin (SCN) at a dose of 2 IU/kg/d s.c. (OVX + SCN); b) alendronate sodium salt (ALN) at a dose of 6 microg/kg/d administered by gavage (OVX + ALN); and c) L-glutamine monofluorophosphate (G-MFP) and calcium at a rate of 1:30 F/Ca at a dose of 0.21 mg F/6.30 mg Ca per kg/d by gavage (OVX + MFP). Significant increases (P < 0.05) of about 15 and 27% in femoral proximal epiphysis bone mineral density (BMD) of the OVX + ALN group were observed versus healthy groups and the OVX group, respectively. The OVX + ALN group also showed significant increases in femoral mid-diaphysis BMD when compared to OVX (18%, P < 0.001), OVX + SCN (14%, P < 0.05) and OVX + MFP (18%, P < 0.001) groups. In the OVX + MFP group, the three-point bending test demonstrated significant increases (P < 0.05) in maximal load of 21 and 22% when compared to the OVX and OVX + SCN groups, respectively. Also, stiffness data showed significant increases of the OVX + MFP (17%) and sham (14%) groups in comparison with the OVX group. A decrease in Mg (42%, P < 0.05), and increases in Ca (15%, P < 0.0001) and PO4 (8%, P < 0.005) content were found by comparing OVX + MFP and OVX groups. Trabecular bone volume results showed significant increases by comparing OVX + ALN and OVX groups (12.20%, P < 0.0005), as well as control groups. Tested agents were able to reduce the bone loss due to estrogen deficiency, but this did not always produce an increase in strength of the treated bone. Alendronate treatment prevented a decrease in bone mineral density and maintained bone mechanical properties after ovariectomy without impairment of bone mineralization in aged rats.

Absorptiometry, Photon↗

PubMed2001

Capecitabine and oxaliplatin in advanced colorectal cancer: a dose-finding study.

PURPOSE: Capecitabine and oxaliplatin are both active anticancer agents in the treatment of patients with advanced colorectal cancer (ACRC). The aim of this dose-finding trial was to determine the maximum-tolerated dose (MTD), the dose-limiting toxicities (DLTs) and the activity of the combination in patients with advanced colorectal cancer. PATIENTS AND METHODS: Twenty-five chemotherapy-pretreated patients received the combination of capecitabine and oxaliplatin. Capecitabine was administered orally twice a day continuously for 14 days in doses ranging from 1,650 to 2,500 mg/m2/d, and oxaliplatin was administered as a two-hour infusion on day 1 using dose, ranges from 100 to 130 mg/m2 repeated every three weeks. RESULTS: Twenty-five patients were assessable for toxicity, and DLTs were diarrhea (grade > or = 3: 27%) and stomatitis (grade > or = 3: 9%) at dose level VI. Dose level V (capecitabine 2500 mg/m2 and oxaliplatin 120 mg/m2) was found to be the MTD. Hematological toxicity was minimal, overall neurotoxicity (grade 1-4) was 27% with 1% grade 3-4. A global response rate was 17% (95% confidence interval (95% CI): 2%-32%) and the median overall survival was 12 months. CONCLUSION: The recommended dose for further phase II studies is capecitabine 2,500 mg/m2/d with intermittent schedule and oxaliplatin 120 mg/m2 every three weeks. The toxicities were mainly gastrointestinal: diarrhea, stomatitis and vomiting. This combination should be studied in phase II trials in advanced colorectal.

Adenocarcinoma↗

PubMed2000

Von Willebrand's factor mediates the adherence of human tumoral cells to human endothelial cells and ticlopidine interferes with this effect.

The aim of this study was to explore whether von Willebrand's factor (vWF) plays a role in the adhesion of human colon tumor cells to human endothelial cells in our coculture system. Cell colony density was evaluated basally (endothelial plus colon tumor cells) and following the addition of: purified vWF, vWF plus vWF-blocking antibodies, antibodies against various integrins and adhesion molecules (alpha2 b integrin, beta1 integrin, beta3 integrin, intercellular adhesion molecule-I, intercellular adhesion molecule-II, vitronectin receptor CD61 CD51, laminin alpha6/beta4 receptor), and various drugs inhibiting the hemostatic system (ticlopidine, heparin, acetyl salicylic acid [ASA], defibrotide, indobuphen, dipyridamole, sulfinpyrazone). Furthermore, vWF concentration was measured in the supernatant fluid of the coculture system basally and following the addition of the above-listed drugs. Cell colony density (as measured by light absorption) increased by 33% following the addition of vWF and returned to a value similar to the basal level with antibodies against vWF, while it did not change significantly following the addition of antibodies against the other integrins or adhesion molecules tested. The same parameter was reduced by 35% following the addition of ticlopidine, while it showed a smaller or no change with the other drugs tested. Similarly, vWF concentration in the cell coculture supernatant showed the greatest reduction (from 0.22 to 0.11 mg/mL) following the addition of ticlopidine. These data suggest that vWF mediates the adherence of human tumor cells to human endothelial cells and that ticlopidine interferes with this effect.

Cell Adhesion↗

PubMed2000

The management of idiopathic thrombotic microangiopathy. Changing trends.

Thrombotic microangiopathy, including the two related syndromes thrombotic thrombocytopenic purpura and hemolytic-uremic syndrome, is a rare and severe multisystem disorder, due to widespread deposition of intravascular microthrombi consisting mainly of platelets, with subsequent consumption thrombocytopenia, microangiopathic hemolytic anemia, renal abnormalities, and neurologic disturbances. The epidemic, verotoxin-induced hemolytic-uremic syndrome, typically associated with prodromal diarrhea, mainly affects young children in small outbreaks. By contrast, idiopathic thrombotic microangiopathy generally affects adults in a sporadic form; it has a more devastating course and a less favourable outcome. Over 90% of the reported cases in the adult, when untreated, have progressed to death within three months of diagnosis. Since the introduction of plasma exchange, a dramatic change in the prognosis of the disease has taken place, although the mortality rate still remains considerable. Indeed, improved survival is the most striking feature of adult thrombotic microangiopathy compared to some decades ago. In the present article we will focus on the evolving concepts able to exert a considerable impact in the management of the adult idiopathic form of thrombotic microangiopathy.

Adult↗

PubMed2000

Nuclear medicine imaging procedures in differentiated thyroid carcinoma patients with negative iodine scan.

Radioiodine treatment following surgery is an effective therapy in differentiated thyroid carcinoma (DTC) patients. However, in DTC patients with metastases characterized by very low or absent iodine uptake, total thyroidectomy and radical loco-regional lymphoadenectomy is the only effective therapeutic approach. In the present article, we have discussed the most recently available nuclear medicine techniques utilized for the detection of DTC metastases that have lost the capacity to trap radioiodine. A review of the data published in the literature has been presented, and a comparative analysis made of the results obtained by other imaging modalities such as high resolution neck ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI). In our experience, the most sensitive and accurate imaging procedure is represented by the combination of neck US and whole body 99mTc-methoxy-isobutylisonitrile (99mTc-MIBI) scintigraphy; this combination might be proposed as a first-line diagnostic approach in DTC patients with increased serum thyroglobulin (Tg) levels and negative high dose 131I scans.

Fluorodeoxyglucose F18↗