Biomedical subjects

G Taddei

Publications and source records attributed to G Taddei.

At least 19 recordsLinked to original sources

PubMed2006

Lymphatic microsurgery for the treatment of lymphedema.

One of the main problems of microsurgery for lymphedema consists of the discrepancy between the excellent technical possibilities and the subsequently insufficient reduction of the lymphoedematous tissue fibrosis and sclerosis. Appropriate treatment based on pathologic study and surgical outcome have not been adequately documented. Over the past 25 years, more than 1000 patients with peripheral lymphedema have been treated with microsurgical techniques. Derivative lymphatic micro-vascular procedures has today its most exemplary application in multiple lymphatic-venous anastomoses (LVA). For those cases where a venous disease is associated to more or less latent or manifest lymphostatic pathology of such severity to contraindicate a lymphatic-venous shunt, reconstructive lymphatic microsurgery techniques have been developed (autologous venous grafts or lymphatic-venous-Iymphatic-plasty - LVLA). Objective assessment was undertaken by water volumetry and lymphoscintigraphy. Subjective improvement was noted in 87% of patients. Objectively, volume changes showed a significant improvement in 83%, with an average reduction of 67% of the excess volume. Of those patients followed-up, 85% have been able to discontinue the use of conservative measures, with an average follow-up of more than 7 years and average reduction in excess volume of 69%. There was a 87% reduction in the incidence of cellulitis after microsurgery. Microsurgical lymphatic-venous anastomoses have a place in the treatment of peripheral lymphedema and should be the therapy of choice in patients who are not sufficiently responsive to nonsurgical treatment. Improved results can be expected with operations performed earlier at the very first stages of lymphedema.

Adolescent↗

PubMed2006

Is there a role for microsurgery in the prevention of arm lymphedema secondary to breast cancer treatment?

The secondary lymphedema of the upper limb (post-mastectomy lymphedema) has an incidence, in patients who underwent axillary lymphadenectomy for breast cancer, between 5 to 25%, up to 40% after radiotherapic treatment. We studied 50 patients treated for breast cancer. The patients were divided in two groups of 25 each, comparable for age, sex, pathology and treatment and followed up to 5 years after operation for breast. One group of 25 patients was controlled only clinically (physical examination, water volumetry) at 1-3-6 months and 1-3-5 years from breast cancer treatment. The other group of 25 patients was followed also by lymphatic scintigraphy performed pre-operatively and after 1-3-6 months and 1-3-5 years from operation. In the first group, followed only clinically, lymphedema appeared in 9 patients after a period variable from 1 week to 2 years, with highest incidence between 3 and 6 months. In the second group of 25 patients, the preventive therapeutic protocol allowed to have a clinically evident arm lymphedema only in 2 patients. The comparison of the two groups of 25 patients proved a statistically significant difference in the appearance of arm secondary lymphedema (p = 0.01, using Fisher's exact test). The diagnostic and therapeutic preventive procedures allow to reduce the incidence rate of lymphedema significantly, in comparison with patients who did not undergo this protocol of prevention.

Adenocarcinoma↗

PubMed2006

Prevalence of oedema of the lower limbs in multiple sclerosis patients: a vascular and lymphoscintigraphic study.

The aim of the study was to evaluate the frequency of oedema of the lower limbs in multiple sclerosis (MS) patients utilizing a multidisciplinary approach. A total of 205 patients with definite MS were included in the study. Seventy-five were male and 130 female, with a mean age of 50.53, mean Expanded Disability Status Scale (EDSS) score of 5.27 and mean disease duration of 16.6 years. Seventy-one patients had a relapsing-remitting (RR) disease course, 85 were secondary progressive (SP) and 49 were primary progressive (PP). Ninety-three patients (45%) showed oedema at the examination. EDSS, disease duration and disease course, but not gender, were statistically different between oedema and non-oedema patients. Out of 93 patients with oedema, 69 agreed to undergo a vascular examination. Of 69 patients, 45 (65.2%) had a CEAP score (specific rating scale for oedema) of 3 (presence of oedema) and 24 (34.8%) had a score of 4 (presence of a trophic disorder). Out of 69 subjects, 33 agreed to undergo a lymphoscintigraphy, which was normal in only 29 extremities out of 66. Lower limb oedema is common in MS patients, especially in those with reduced mobility. Early screening is advised in patients with an elevated EDSS.

Adult↗

PubMed2005

Diagnostic protocol for lymphoscintigraphy in newborns.

The purpose of this methods paper is to offer pediatricians and nuclear medicine physicians a diagnostic protocol for performing lymphoscintigraphy in newborns that may be useful for enhancing diagnosis and management of newborns with congenital lymphatic abnormalities. Indications for lymphoscintigraphy, choice of tracer, optimal dose, routes of administration, methods of data acquisition, timing, and interpretation of results for newborns are presented and discussed.

Diagnosis, Differential↗

PubMed2005

Pulmonary lymphangiectasia.

Congenital pulmonary lymphangiectasia (PL) is a rare developmental disorder involving the lung and is characterized by pulmonary subpleural, interlobar, perivascular, and peribronchial lymphatic dilatation. Both frequency and etiology are unknown. PL presents at birth with severe respiratory distress, tachypnea, and cyanosis, with a very high mortality rate at or within a few hours of birth. At birth, mechanical ventilation and pleural drainage are nearly always necessary to obtain a favorable outcome of respiratory distress. Home supplemental oxygen therapy and symptomatic treatment of recurrent cough and wheeze are often necessary during childhood, sometimes associated to prolonged pleural drainage. Recent advances in intensive neonatal care have changed the previously nearly fatal outcome of PL at birth. Patients affected by PL who survive infancy present medical problems which are characteristic of chronic lung disease.

Diagnosis, Differential↗

PubMed2004

Multimodal imaging in the congenital pulmonary lymphangiectasia-congenital chylothorax-hydrops fetalis continuum.

We report on three infants with congenital chylothorax (CC) and congenital pulmonary lymphangiectasia (CPL). CPL appears to be a characteristic pathological finding in CC. Through the use of lymphoscintigraphy and computed tomography, this study suggests that CC and CPL are strongly correlated entities and that the dysplasia of the lymphatic system results in a pulmonary lymphatic obstruction sequence. The initial microscopic dilatation of the lymph channels may lead to progressive weeping of lymphatics and, consequently, to pleural effusion. Non-Immune Hydrops Fetalis (NIHF) may be the final consequence of impaired systemic venous return and may help to explain pleural-pulmonary involvement in this generalized lymph-vessel malformation syndrome.

Abnormalities, Multiple↗

PubMed2001

Contribution of NK3 tachykinin receptors to propulsion in the rabbit isolated distal colon.

The role of NK3 receptors in rabbit colonic propulsion has been investigated in vitro with the selective agonist, senktide, and two selective antagonists, SR142801 and SB222200. Peristalsis was elicited by distending a rubber balloon with 0.3 and 1.0 mL of water leading to a velocity of 2.2 and 2.8 mm s-1, respectively. At concentrations of 1 nM, senktide inhibited propulsion evoked by both distensions (range 25-40%), whereas at 6 and 60 nmol L-1 facilitated 'submaximal' propulsion by 30%. In the presence of Nomega-nitro-L-arginine (L-NNA, 200 micromol L-1), which per se caused a slight prokinetic effect, 1 nmol L-1 senktide markedly accelerated propulsion (range 35-50%). Hexamethonium (200 micromol L-1) had minor effects on propulsion. In its presence, 60 nmol L-1 senktide significantly inhibited propulsion induced by both stimuli (range 20-50%). SR142801 (0.3, 3 nmol L-1) and SB222200 (30, 300 nmol L-1) facilitated 'submaximal' propulsion (range 20-40%). Conversely, higher antagonist concentrations (SR142801: 30, 300 nM; SB222200: 1, 10 micromol L-1) inhibited propulsion to both distensions by 20%. A combination of SR142801 (300 nmol L-1) plus hexamethonium (200 micromol L-1) induced an approximately four-fold greater inhibition of propulsion than that induced by SR142801 alone. In conclusion, in the rabbit-isolated distal colon, a subset of NK3 receptors located on descending pathways mediates an inhibitory effect on propulsion by activating a NO-dependent mechanism. Another subset of NK3 receptors, located on ascending pathways mediates a facilitative effect involving a synergistic interaction with cholinergic nicotinic receptors.

Animals↗

PubMed2001

Ageing of the human oviduct: lectin histochemistry.

The aim of the present research was to investigate the changes of the sugar residues in the oviduct in the course of ageing in postmenopausal women vs normally menstruating women, by means of lectin histochemistry. Twenty asymptomatic postmenopausal women (48-83 years old) were recruited among patients who underwent a vaginal hysterectomy. Eight normally menstruating women were recruited as controls. Fragments of Fallopian tubes (pars ampullaris) were fixed in 10% formalin and routinely processed. The sections were labelled with HRP-lectins (PNA, SBA, DBA, WGA, Con A, LTA, UEAI). Some sections were pre-treated with neuraminidase prior to staining with HRP-lectins. Among the postmenopausal patients, our histochemical data showed that there was no difference in the localization and distribution of sugar residues of glycoconjugates as detected by various HRP-lectins. Moreover, our results demonstrated that the oviductal epithelium is characterized by apical reactivity in both ciliated and non-ciliated cells. In the course of ageing, the ciliated cells changed their morphology from bathyprismatic to large and rounded shape. ConA lectin reacted intensely with such highly degenerating ciliated cells and could be considered a marker of these cells. The degenerating ciliated cells are also characterized by the absence of sialic acid. In comparison with the sugar residues present in the control group, the oviductal epithelium of postmenopausal women is characterized by the loss of reactivity with DBA, WGA and ConA. Moreover, PNA reactive material was present at the free border of the ciliated and non-ciliated cells. The latter findings were statistically confirmed and could be considered strictly related to the ageing process.

Aged↗

PubMed2000

Hippocampal perfusion in mild Alzheimer's disease.

Perfusion and metabolic studies in patients with Alzheimer's disease (AD) have so far yielded conflicting results on the functional status of the hippocampal region, whose deep location in the brain makes it critical to optimize the image-reconstruction technique employed in emission tomography. We used a brain-dedicated device (CERASPECT) to perform single photon emission computed tomography (SPECT) studies with 99mTc-hexamethylpropylene-amine-oxime in 22 consecutive patients (mean age: 74+/-6.5 years) with mild [mini-mental status examination (MMSE) score > or =15, mean 20.8+/-3.2], probable AD. The control subjects were 11 healthy elderly people (mean age: 70.5+/-6.5 years). In patients, the total score on the selective reminding test (SRT) was used as an index of memory function. Counts from a hippocampal and a temporoparietal region of interest in each hemisphere were referred to the average thalamic counts. To optimize SPECT images, we used conventional filtered back-projection (FBP) reconstruction and a new iterative method of conjugate gradients (CG), which takes into account the geometrical and physical characteristics of the gamma-camera. Hippocampal perfusion in the two hemispheres was significantly lower in patients than in control subjects, regardless of which reconstruction method was used, and correlated with the MMSE score. The correlation between hippocampal perfusion and the SRT score was significantly (bootstrap procedure) higher with the CG method than with the FBP method (CG: r=0.52 and 0.54; FBP: r=0.39 and 0.47, for the right and left hemisphere, respectively). These results show hippocampal hypoperfusion in patients with mild AD, a correlation between hippocampal perfusion and the severity of cognitive impairment, and enhanced identification of these subtle perfusional changes with the use of an alternative image-reconstruction method that improves the spatial resolution of SPECT images.

Aged↗

PubMed2000

Inhibitory effect of luteinising hormone-releasing hormone analogues on human endometrial cancer in vitro.

We studied the effects of luteinising hormone-releasing hormone (LHRH) agonist leuproreline (1 microM for 96 h) and LHRH antagonist cetrorelix on the cell growth of primary cultures from nine human endometrial cancers using the sulphorhodamine colorimetric test. Histological examinations and reverse transcription and polymerase chain reaction amplification (RT-PCR) for LHRH receptors were also performed. The endometrial cancers examined had a medium to high degree of proliferative activity and a low degree of apoptotic power; furthermore, they expressed the LHRH receptor RNA variably, detectable in 71% of cases. The addition of leuproreline or cetrorelix to cell cultures inhibited growth in a statistically significant way compared to untreated control cells; nevertheless, the percentage of cell growth inhibition obtained was very variable. These data suggest that LHRH analogues can exert differential inhibitory effects on the growth of endometrial cancer, which seems to be independent of the expression of specific LHRH receptors.

Aged↗

PubMed2000

Giant pelvic retroperitoneal liposarcoma.

BACKGROUND: Pelvic retroperitoneal liposarcomas are rare in young women (under 30 years old). We present a case of a giant well-differentiated liposarcoma of the retroperitoneum in a young woman. CASE: A 27-year-old nulligravida presented with rapid abdominal enlargement. Pelvic examination found a huge mass extending from the left adnexa to the epigastric region. At surgery, the pelvic organs were displaced to the right side by a retroperitoneal mass that marginally involved the left fallopian tube. The left ovary, uterus, and right adnexa were not involved and were not removed. No adjuvant irradiation was given. The patient was alive and well 2 years after the operation and was 23 weeks pregnant. CONCLUSION: Gynecologists should be familiar with pelvic retroperitoneal liposarcomas and their treatment.

Adult↗

PubMed2000

Contribution of NK(2) tachykinin receptors to propulsion in the rabbit distal colon.

The role of the tachykinin neurokinin (NK)(2) receptors on rabbit distal colon propulsion was investigated by using two selective NK(2)-receptor antagonists, MEN-10627 and SR-48968. Experiments on colonic circular muscle strips showed that contractile responses to [beta-Ala(8)]NKA-(4-10) (1 nM-1 microM), a selective NK(2)-receptor agonist, were competitively antagonized by MEN-10627 (1-100 nM), whereas SR-48968 (0.1-10 nM) caused an insurmountable antagonism, thus confirming the difference in the mode of action of the two compounds. Colonic propulsion was elicited by distending a mobile rubber balloon with 0.3 ml (submaximal stimulus) or 1.0 ml (maximal stimulus) of water. The velocity of anal displacement of the balloon (mm/s) was considered the main propulsion parameter. At low concentrations (1.0-100 nM and 0.1-10 nM, respectively), MEN-10627 and SR-48968 facilitated the velocity of propulsion, whereas at high concentrations (100 nM and 1 microM, respectively) they decelerated propulsion. The excitatory and inhibitory effects of both antagonists were observed only with submaximal stimulus. We focused on the hypothesis that the facilitatory effect on propulsion may result from blockade of neuronal NK(2) receptors and the inhibitory effect from suppression of the excitatory transmission mediated by NK(2) receptors on smooth muscle cells. In the presence of N(G)-nitro-L-arginine (300 microM), a nitric oxide synthase inhibitor, MEN-10627, at a concentration (10 nM) that was found to accelerate propulsion in control experiments inhibited the velocity of propulsion. In the presence of threshold (1-10 nM) or full (1 microM) concentration of atropine, which inhibited to a great extent the velocity of propulsion, the inhibitory effect of MEN-10627 (1 microM) was markedly increased. In conclusion, in the rabbit distal colon NK(2) receptors may decelerate propulsion by activating a nitric oxide-dependent neuronal mechanism and may accelerate it by a postjunctional synergistic interaction with cholinergic muscarinic receptors.

Animals↗

PubMed1999

Dextran sulfate sodium (DSS) colitis in rats: clinical, structural, and ultrastructural aspects.

Aim of this study was to assess the structural, ultrastructural, immunohistochemical, and clinical aspects in Sprague-Dawley rats with dextrane sulfate sodium (DSS)-induced colitis. Colitis was induced in Sprague-Dawley rats by seven days of DSS oral administration followed by seven days of tap water only (for one, two and three cycles). Controls were fed with water only. Segments of proximal, mid-, and distal colon of each animal were adequately prepared for light and scanning electron microscope observations. The severity of the lesions was scored histologically. For immunohistochemical study, a cocktail of S-100, NSE, and antineurofilament antibodies was used. Symptoms such as weight, feces consistency, diarrhea, hematochezia were recorded daily. From a clinical point of view symptoms appeared significantly later after the first cycle than after the second and third cycles and lasted significantly longer in the second and third cycles. Treated rats showed a slower weight gain rate by 20% compared to controls, and the whole colon length appeared to be significantly shorter after colitis induction compared to controls. Structural observations by light microscopy showed prominent involvement of the distal colon. Immunohistochemical study of both submucosal and myoenteric nerve plexuses was similar to controls. Scanning electron microscope observations of the colonic mucosal surface in colitis rats showed a complete subversion of its architecture, characterized by dilatations of gland crypt openings, dropout of goblet cells, and inhomogeneous distribution or lack of microvilli. These were most evident after the third cycle. In conclusion, experimental DSS colitis in SD rats appeared to be highly reproducible and shared most features with human UC, not only from a structural and clinical but also from an ultrastructural point of view.

Animals↗

PubMed1999

99mTc-HMPAO regional cerebral blood flow and quantitative electroencephalography in Alzheimer's disease: a correlative study.

UNLABELLED: In this study the neuropsychological status of patients with Alzheimer's disease (AD) was correlated with quantitative electroencephalography (qEEG) and regional cerebral blood flow (rCBF) both in the cortex and in deep gray matter structures. METHODS: Forty-three outpatients (mean age 72.4 +/- 7.5 y) with probable AD underwent 99mTc-hexamethyl propyleneamine oxime SPECT with a brain-dedicated gamma camera and qEEG (relative values) within 1 mo. Preliminary factorial analysis with promax rotation identified four qEEG bands (2-5.5, 6-7.5, 8-11.5 and 12-22.5 Hz, with no distinction as to topography) and six SPECT regions (the two thalami together, the two parietal cortices together, the right temporal cortex, the right hippocampus, the left hippocampus and the remaining cortical areas together) as the variables with highest statistical power. All these variables and the Mini-Mental Status Examination score (MMSE, a sensitive marker of neuropsychological deficit) were processed by a final factorial analysis and multivariate analysis of variance. RESULTS: Both the 2-5.5 Hz and the 8-11.5 Hz powers were correlated with the perfusion level in the parietal regions of interest (ROls) (P = 0.0009), whereas the 2-5.5 Hz power was correlated with the right hippocampal perfusion level (P = 0.007). The MMSE score was significantly correlated with the perfusion level, both in the right (P = 0.006) and in the left (P = 0.004) hippocampal ROls and in the parietal ROls (P = 0.01); moreover, it was correlated with both the 2-5.5 Hz (P = 0.0005) and the 8-11.5 Hz (P = 0.004) power. CONCLUSION: rCBF (bilateral parietal perfusion) and qEEG (especially the slowest frequencies, i.e., 2-5.5 Hz) are confirmed to be good descriptors of AD severity. It is especially noteworthy that bilateral hippocampal CBF was the perfusional index best correlated with the MMSE as well as being significantly correlated to qEEG. Hippocampal SPECT imaging appears to be a promising index to improve characterization of AD in respect to other forms of primary degenerative dementia and may be proposed as a marker for evaluating the effects of pharmacotherapy of AD at the neuronal level.

Aged↗

PubMed1999

"Crohn's disease activity index" is inaccurate to detect the post-operative recurrence in Crohn's disease. A GISC study. Gruppo Italiano per lo Studio del Colon e del Retto.

BACKGROUND: Even though endoscopy is considered to be the gold standard for the detection of post-operative recurrence in Crohn's disease, the Crohn's disease activity index continues to be used for this purpose. AIM: The aim of this study was, therefore, to assess the accuracy of Crohn's disease activity index to detect post-operative recurrence in Crohn's disease in comparison to endoscopy. PATIENTS AND METHODS: The study was performed in 110 patients submitted to intestinal resection for Crohn's disease of the terminal ileum. Crohn's disease activity index score was assessed at 6, 12, 24 and 36 months after surgery. At the same intervals colon-ileoscopy was performed in all patients. The Receiver Operating Characteristic analysis was used to assess the accuracy of the Crohn's disease activity index score. Some routine laboratory variables were also analyzed. RESULTS: Crohn's disease activity index was able to discriminate patients with and without recurrence in 65% of the cases. Considering 150 the standard cut-off value of Crohn's disease activity index, this figure corresponds to a specificity of 89% and a sensitivity of 30%. Out of the laboratory variables erythrocyte sedimentation rate, chloraemia and serum albumin, globally considered in a discriminant function, showed a predictive ability significantly better than Crohn's disease activity index (z = 1.97; two tailed p-value = 0.04). These variables were able to discriminate patients with and without recurrence in 88% of the cases, and at the same value of specificity for the Crohn's disease activity index reached double value of sensitivity (65%). Positive and negative predictive values of laboratory variables (80% and 78%, respectively) were better than the corresponding values of the Crohn's disease activity index score (71% and 56%, respectively). CONCLUSIONS: These results indicate that the Crohn's disease activity index alone is inadequate for detection of post-operative recurrence in Crohn's disease.

Blood Cell Count↗

PubMed1999

Regulatory role of tachykinins on intestinal propulsive activity.

The role of NK1, NK2, NK3 tachykinin receptors in subserving intestinal peristalsis has been reviewed referring mainly to the latest advances in this field. The most interesting and intriguing notion emerging from recent and ongoing studies is that tachykinins present in enteric neurons may modulate propulsive activity in an opposite manner, by enhancing or inhibiting peristalsis via each of the three distinct tachykinin receptors. These studies unveiled the complexity of tachykinergic control of the intestinal motility which is due to interaction of endogenous tachykinins with receptors located on ascending excitatory and descending inhibitory pathways and on smooth muscle cells. In fact, the type of tachykinergic modulation may depend on the amount of released peptides, on the site of the bulk of peptide release along the enteric motor pattern and, consequently, on the cellular location of the activated receptor, i.e. muscular or neuronal cells. Furthermore, in the case of activation of neuronally located tachykinin receptors, the effect of tachykinins may depend on the relatively functional predominance of excitatory or inhibitory neural circuits subserving peristalsis in different intestinal tracts. Our findings obtained in a simple isolated model represent a promising start for the understanding of the complex tachykinergic modulatory role of intestinal motility even though the function of tachykinins studied "in vivo" is certainly more complex than that studied "in vitro".

Animals↗

PubMed1998

Feasibility in the clinical setting of perfusion brain SPECT imaging employing a brain-dedicated gamma camera and the conjugate gradients with modified matrix reconstruction method.

In the present study, we compared Tc-99m HMPAO single photon emission computed tomography (SPECT) brain images obtained using the conventional filtered backprojection (FBP) reconstruction method with the new reconstruction method of conjugate gradients with modified matrix (CGMM). The two methods were employed to generate SPECT images of a brain perfusion study in a 41-year-old patient who had suffered from multiple embolisation of the right hemisphere. Marked improvement in spatial resolution was achieved by CGMM reconstruction as compared to FBP reconstruction; this considerably helped in defining grey matter structures and low-uptake white-matter areas, both in the normal cerebral areas and in the hemisphere that had been affected by stroke. Although the relatively long time still required by the CGMM procedure might be considered as a significant drawback to date, with the increasing diffusion of the new computer facilities the CGMM method can be proposed as a valuable alternative to the standard FBP technique in order to better recognise cerebral areas with different tracer uptake.

Adult↗

PubMed1998

A theoretical four-compartment model to evaluate separate kidney technetium-99m-MAG3 kinetics in humans.

BACKGROUND: Pharmacokinetic modeling based on compartmentalization has provided a valuable tool to assess the clearance patterns of various glomerular and tubular agents. However, no models have been proposed thus far that combine vascular data and imaging data in order to gain a deeper knowledge on renal pathophysiology, and to obtain more diagnostic information of clinical relevance. To this aim, we propose a four-pool model for the evaluation of separate renal function. METHODS: In a group of ten normal volunteers and twenty patients with various renal diseases, we tested the four-pool model based on the identification of the two kidneys as two distinct pools. This approach made it possible to integrate the separate kidney contributions deriving from in vivo imaging data, and allows the researcher to quantitate many parameters specific to each kidney. RESULTS: The parameters TERR, TERL, MRTR, MRTL, vR, vL, k3R-1, K3L-1 permit the normal from abnormal states of renal function to be differentiated, as well as monolateral from bilateral renal disease to be separated within the abnormal function group. CONCLUSIONS: The proposed approach combines the advantages of plasma clearance methods with those derived by gamma-camera imaging, and makes it possible to quantitate the differential renal function. This feature may be clinically relevant in renal transplant donors, where full knowledge of renal pathophysiology could guide the procedure.

Adult↗