Biomedical subjects

G Madeddu

Publications and source records attributed to G Madeddu.

At least 19 recordsLinked to original sources

PubMed2005

[99mTc]sestamibi and [99mTc]tetrofosmin in oncology: SPET and fusion imaging in lung cancer, malignant lymphomas and brain tumors.

[(99m)TC]sestamibi and [(99m)TC]tetrofosmin are two lipophilic cationic complexes which were originally employed in myocardial perfusion imaging and then later applied as tumor-seeking agents in the evaluation of diverse human malignancies. Despite the wider use of fluorine-18-labeled fluorodeoxyglucose positron emission tomography (FDG-PET) in cancer imaging, the two cationic lipophilic agents still play a useful clinical role in oncology when single-photon emission computed tomography (SPET) instead of planar is used as the acquisition method. This review summarizes the results of studies on the use of these radiopharmaceuticals in lung cancer, malignant lymphomas and brain tumors. Their performance in the diagnosis and staging of the primary tumor, the prediction of cancer response to therapy, the monitoring of treatment and the detection of recurrence during follow-up is also compared. Numerous studies have shown that SPET procedures are highly sensitive and accurate in tumor patient management. However, the main limitation to both SPET and planar imaging alike is that under some conditions the images do not give a clear structural delineation of the pathologic processes detected with these procedures. This sometimes makes SPET images difficult to interpret and so reduces its diagnostic performance. Recently available hybrid SPET/CT devices appear to overcome this problem by providing both functional and anatomical data. Preliminary reports on SPET/CT in tumor imaging have demonstrated that SPET/CT can provide more clinical information than SPET or CT alone in some cases. The possible role of integrated dual-modality images using SPET with SM or TF is also briefly discussed.

Brain Neoplasms↗

PubMed2005

99mTc labelled cationic lipophilic complexes in malignant and benign tumors: the role of SPET and pinhole-SPET in breast cancer, differentiated thyroid carcinoma and hyperparathyroidism.

Single photon emission tomography (SPET) represents an indispensable diagnostic tool in nuclear medicine. Due to better contrast resolution, cross sectional and 3D images, SPET plays a useful complementary tool to bidimensional planar scintigraphy in certain clinical conditions, while representing the procedure of choice in others. However, high resolution SPET with pinhole collimator (P-SPET) can improve conventional SPET sensitivity with parallel hole collimators. This review summarizes data on the employment of conventional SPET and P-SPET in breast cancer, differentiated thyroid cancer (DTC) and hyperparathyroidism patients, using the cationic lipophilic complexes [(99m)Tc]metoxy isobutyl isonitrile (sestaMIBI) and [(99m)Tc]tetrofosmin as oncotropic radiotracers. In breast cancer patients, SPET with these radiotracers can play an important complementary role to planar scintimammography in detecting primary tumors, especially when non palpable and small in size, whereas SPET and particularly P-SPET represents the procedure of choice in preoperative axillary lymph node status evaluation in which planar is almost always irrelevant. In DTC follow-up patients, SPET and P-SPET with cationic lipophilic radiotracers are indicated in both locoregional and distant metastasis detection, especially in patients with high Tg serum levels and negative radioiodine scanning in whom these procedures represent a reliable alternative to diagnostic (131)I scanning. Moreover, the combined use of [(99m)Tc]tetrofosmin P-SPET and US can identify recurrences and lymph node metastases in the neck, both fixing and non fixing iodine, downstaged or negative at (131)I scanning. SPET can also be a useful complementary tool to planar parathyroid scintigraphy in the detection and localization of small and ectopic parathyroid adenomas in the neck or mediastinum, while neck P-SPET seems to also significantly increase planar sensitivity in hyperplastic glands. SPET and P-SPET are indicated in persistent and recurrent hyperparathyroidism including from carcinoma.

Breast Neoplasms↗

PubMed2004

Oxidative and genotoxic damage after radio-iodine therapy of Graves' hyperthyroidism.

PURPOSE: To evaluate genetic damage and oxidative stress following a single therapeutic dose of 131I in Graves' disease patients monitored up to 180 days after treatment. MATERIALS AND METHODS: Genetic damage induction was estimated as the increase in micronuclei in peripheral lymphocytes of patients. As indicators of radiogenic oxidative stress, vitamin E and lipoperoxide levels were assessed in the plasma of patients, as well as the release of plasmic clastogenic factors measured by the induction of micronuclei in vitro in peripheral lymphocytes of a healthy donor. RESULTS: Vitamin E depletion lasted at least 3 days and the basal level was restored within 7 days. No statistically significant variations were observed in lipoperoxide plasma levels. A sharp increase of micronuclei in the peripheral lymphocytes of patients was correlated (p < 0.001) with the release of clastogenic factor in the plasma. The highest micronucleus value was negatively correlated (p < 0.03) with the lowest vitamin E level observed in each patient. CONCLUSIONS: Micronuclei induction was the direct consequence not only of the energy deposition of 131I on the genetic material, but also of oxidative stress, likely via the release of clastogenic factor.

Adult↗

PubMed2003

The usefulness of 99mTc tetrofosmin scintigraphy in patients with breast cancer recurrences.

To verify the usefulness of 99mTc tetrofosmin scintigraphy in the follow-up of breast cancer patients, we studied 72 surgically treated breast cancer patients with suspected local recurrences (20 cases) or distant metastases (52 cases) at clinical examination and/or at conventional imaging procedures (CIPs). In all patients, a whole-body scan followed by planar and single photon emission tomography (SPET) images of selected sites were acquired 10 min after the intravenous injection of 740 MBq of 99mTc tetrofosmin, using a rectangular dual-head gamma camera equipped with high-resolution parallel-hole collimators. Loco-regional recurrences were diagnosed in 19 patients and distant metastases in 44 cases, while benign lesions were ascertained in nine cases. 99mTc tetrofosmin SPET showed higher sensitivity, specificity and accuracy per patient than did CIP (96.8% vs 85%, 77.7% vs 55.5% and 94.4% vs 81.1%, respectively) with statistical significance for accuracy (P <0.05). The combined use of SPET and CIP achieved 100% sensitivity and 98.6% accuracy. Planar imaging did not give additional information in respect of either SPET or CIP, showing significantly lower sensitivity and accuracy values (47.6% and 52.8%, respectively). Our data seem to suggest that 99mTc tetrofosmin SPET, but not planar, may be useful in the follow-up for the detection of loco-regional and distant recurrences in patients with breast cancer. The technique can play a complementary role to conventional diagnostic imaging procedures in selected patients.

Adult↗

PubMed2003

Usefulness of 99mTc-tetrofosmin scintigraphy in different variants of Kaposi's sarcoma.

We investigated (99m)Tc-tetrofosmin scintigraphy in 27 patients with Kaposi's sarcoma: 20 had classic (CK), 5 AIDS-associated (AK) and 2 transplantation-associated (TK) variants. Twenty-three patients had clinically evident cutaneous and/or mucosal lesions, 9 of them with associated sarcomatous lymphadenopathy; 2 TK patients had only lymph nodes or other extracutaneous Kaposi sites. Both planar and SPECT (99m)Tc-tetrofosmin scintigraphies were performed in all cases and neck pinhole (P)-SPECT in selected patients. (99m)Tc-tetrofosmin uptake was observed in 88% of patients with clinically evident cutaneous and/or extracutaneous Kaposi lesions. Scintigraphy gave additional information on cutaneous lesion extent, particularly SPECT regarding deep invasion and subclinical sites in some cases. However, scintigraphy was less sensitive in the detection of small, isolated and scattered lesions. SPECT/P-SPECT were positive in 8/8 patients with sarcomatous lymph nodes, planar imaging in 5/8, ultrasonography in 7/8, while all procedures were negative in 6 other patients with reactive or HIV infection lymph nodes. SPECT demonstrated lymphadenopathy remission in 1 TK patient after immunosuppressive therapy modification and, like planar imaging, ascertained an associated lymphoma with (67)Ga-citrate combined. (99m)Tc-tetrofosmin scintigraphy, especially SPECT, can be useful both in the detection and staging of Kaposi sarcoma lesions as a complementary tool to clinical and other conventional diagnostic methods.

Aged↗

PubMed2003

The role of (99m)Tc-tetrofosmin pinhole-SPECT in breast cancer non palpable axillary lymph node metastases detection.

AIM: We evaluated the usefulness of (99m)Tc-tetrofosmin axillary pinhole (P)-SPECT in breast cancer (BC) non palpable axillary lymph node metastasis detection compared with conventional planar and SPECT scintimammography. METHODS: We studied prospectively 188 consecutive patients with suspected primary BC, negative at axillary clinical examination. Ten minutes after 740 MBq (99m)Tc-tetrofosmin injection, planar and SPECT scintimammography were acquired, followed by axillary P-SPECT imaging. RESULTS: At histology, 12 patients had benign mammary lesions and 176 had BC. Axillary lymph node dissection (ALND) was performed in all BC patients, bilaterally in 3 cases: 74/179 axillae had metastases. P-SPECT showed a significantly higher overall sensitivity than SPECT and planar (93.2% vs 85.1% and 36.5%, respectively; p<0.05 and p<0.0005, respectively) and was false negative in 5 patients with 1 metastatic node each, micrometastatic in 4/5 cases; SPECT and planar were also false negative in these 5 cases and in 6 and in 42 further cases, respectively. P-SPECT added important prognostic information by distinguishing single from multiple and pound 3 from >3 nodes; only P-SPECT defined the exact number of nodes in 15/25 patients with 2-4 nodes. P-SPECT showed the highest accuracy and NPV: 92.7% and 95%, respectively (SPECT 90.5% and 90%, respectively; planar 73.2% and 68.9%, respectively). CONCLUSION: (99m)Tc-tetrofosmin axillary P-SPECT appears highly accurate in BC non palpable axillary lymph node metastasis detection and significantly more sensitive than both planar and SPECT, its few false negative results predominantly concerning micrometastases; moreover, only P-SPECT gave additional important prognostic information. Given its very high NPV, P-SPECT could also be used to better select patients who might avoid ALND.

Adult↗

PubMed2001

(99)mTc-tetrofosmin SPET in the detection of both primary breast cancer and axillary lymph node metastasis.

The aim of this study was to evaluate the usefulness of (99m)Tc-tetrofosmin single-photon emission tomography (SPET) in the detection of both primary breast cancer and axillary lymph node metastasis. We studied 192 consecutive patients in whom primary breast cancer was suspected on the basis of mammography and/or physical examination. After intravenous injection of 740 MBq (99m)Tc-tetrofosmin, both planar and SPET scintimammography was performed in all patients using a rectangular dual-head gamma camera equipped with low-energy, high-resolution, parallel-hole collimators. In 175 patients with breast cancer at histology, the per-lesion overall sensitivity of SPET and planar imaging for the detection of breast cancer was 95.8% and 75.9% (P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 96.5% and 79.5% in palpable (P<0.0005) and 90% and 45% in non-palpable lesions (P<0.01). With regard to lesion size, the sensitivity of SPET and planar imaging was, respectively, 90.5% and 45.2% in lesions < or =10 mm ( P<0.0005), 95.3% and 81.4% in lesions of 11-20 mm (P<0.005), 100% and 84.6% in lesions of 21-30 mm (P<0.05) and 100% and 95.8% in lesions >30 mm (P>0.05). In the remaining 17 patients with benign mammary lesions at histology, per-lesion overall specificity of SPET and planar imaging was 76.2% and 85.7% (P>0.05), respectively. Neither SPET nor planar imaging showed false-positive results in non-palpable lesions or in those < or =10 mm. In 173 breast cancer patients submitted to axillary lymph node dissection (ALND), per-axilla overall sensitivity of SPET and planar imaging in the detection of axillary lymph node metastasis was 93% and 52.3% ( P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 100% and 82.6% in palpable nodes (P>0.05), 90.5% and 41.3% in non-palpable nodes (P<0.0005), 92.8% and 35.7% in the presence of < or =3 nodes ( P<0.0005) and 93.2% and 68.2% in the presence of >3 nodes (P<0.005). The specificity of SPET and planar imaging was 91% and 100% (P<0.05), respectively. (99m)Tc-tetrofosmin SPET appears to be a reliable method for the detection of both primary BC and axillary lymph node metastasis, and its diagnostic accuracy exceeds that of (99m)Tc-tetrofosmin planar scintimammography. The use of SPET is particularly important in the identification of small non-palpable primary carcinomas and metastatic axillae with < or =3 non-palpable lymph nodes. More extensive use of SPET appears warranted in the management of breast cancer patients.

Axilla↗

PubMed2001

Impact of early pelvic floor rehabilitation after transurethral resection of the prostate.

We examined the results of teaching pelvic floor muscle exercises (PME) on micturition parameters, urinary incontinence, post-micturition dribbling, and quality of life in patients after transurethral prostatectomy (TURP). Fifty-eight consecutive patients who were selected to undergo TURP for benign prostatic hyperplasia (BPH) were admitted into the study: 28 were randomly assigned to a control group (A), 30 formed the investigational group (B) during an initial visit conducted before surgery. In group B patients, perineal exercises were demonstrated in detail, and tested for their correct use via simultaneous rectal and abdominal examination. After the removal of the urethral catheter, these patients were instructed to perform pelvic floor muscle exercises at home and were evaluated before the exercises and at weekly intervals postoperatively. The American Urological Association Symptom Score improved significantly after TURP in both groups. The average quality of life score improved more significantly in group B after TURP, from 5.5 to 1.5 (P < 0.001). The grade of muscle contraction strength after 4 weeks of PME increased from 2.8 to 3.8 in group B (P < 0.01); it was unchanged in the group A. The number of patients with incontinence episodes and post-micturition dribbling was significantly lower in the group B at weeks 1, 2, and 3 (P < 0.01). Our results show that pelvic floor muscle re-education produces a quicker improvement of urinary symptoms and of quality of life in patients after TURP. Its early practice reduces urinary incontinence and post-micturition dribbling in the first postoperative weeks. The exercises are simple and easy to perform in the clinical setting and at home, and therefore should be recommended to all cooperative patients after TURP.

Aged↗

PubMed2001

99mTc-Tetrofosmin pinhole-SPECT (P-SPECT) and radioguided sentinel node (SN) biopsy and in breast cancer axillary lymph node staging.

We compared 99mTc-Tetrofosmin P-SPECT with radioguided SN biopsy in 101 T1/T2 BC pts to predict axillary lymph node status. The day before surgery all pts underwent lymphoscintigraphy (LS) to mark the SN, following subdermal injection of 99mTc-colloidal sulphur surrounding the breast lesion. LS was combined with pre and intraoperative gamma probe. Previously, all pts had also undergone P-SPECT. ALND was performed in all cases. The SN(s) was detected in 97/101 cases (96%) by LS and gamma probe; in the 4 missed cases P-SPECT predicted lymph node status. In the 97 comparable cases, radioguided SN biopsy showed a slightly higher accuracy than P-SPECT (94.8% vs 93.8%), but a higher false-negative rate (14.3% vs 8.6%); P-SPECT had a higher NPV (95.2% vs 92.5%). The two procedures when combined achieved 100% accuracy. Radioguided SN biopsy alone had 100% accuracy only in pts with BC < 15 mm. P-SPECT had 3 false negative cases, 2 of which were micrometastatic SNs, and 3 false positives. P-SPECT identified 81.2% of cases with a single node, determined the exact number of nodes in 82.6% of cases with 1 to 3 node and correctly classified 93.7% of pts as having < or = 3 or > 3 metastatic nodes. Radioguided SN biopsy seems indicated in selected, early stage, small BC pts, while P-SPECT shows a high sensitivity independent of primary tumor size, giving additional important preoperative prognostic information. The two procedures combined provided a better axillary lymph node status prediction in T1/T2 carcinomas, and could thus improve ALND pt selection.

Adult↗

PubMed2000

The role of 99mTc-tetrofosmin Pinhole-SPECT in breast cancer axillary lymph node staging.

The number of metastatic axillary nodes represents one of the most important prognostic factors in preoperative breast cancer patients. 99mTc-Tetrofosmin high resolution Pinhole (P)-SPECT was employed in 112 patients, 100 with breast cancer and 12 with benign mammary lesions, to ascertain axillary lymph node involvement. Axillary P-SPECT images were acquired utilizing specific software connected to a circular high resolution, single-head gamma camera equipped with a pinhole collimator with aperture size of 4.45 mm, rotating 180 degrees around the involved axilla. At the same time, patients also underwent conventional SPECT and planar acquisitions. Per-patient sensitivity and specificity were 100% and 93.6% for P-SPECT, 96.2% and 93.6% for SPECT and 56.6% and 100% for planar imaging, respectively. Moreover, P-SPECT detected more than 51% of lesions ascertained by histology, whereas SPECT and planar detected 32.6% and 20.3%, respectively. Only P-SPECT succeeded in identifying the exact number of metastatic axillary lesions in patients with multiple nodes; this procedure was able to correctly differentiate 88.67% of patients with 3 or less nodes from those with more than 3, thus giving important prognostic information. These data suggest 99mTc-Tetrofosmin P-SPECT is a reliable imaging method both for staging and prognostic purposes in breast cancer, and its routine use is recommended.

Adult↗

PubMed2000

Clinical evaluation of percent free prostate-specific antigen using the AxSYM system in the best analytical scenario.

OBJECTIVE: Percent free prostate-specific antigen (PSA) is a promising tool for prostate cancer (CaP) diagnosis. However, its diagnostic performances have not yet been established. The present study was carried out with the aim of evaluating percent free PSA in the most favourable analytical conditions. MATERIALS AND METHODS: Eighty-eight patients affected by newly diagnosed, untreated, primary CaP, and 169 cases with biopsy-confirmed, untreated, benign prostatic hypertrophy (BPH) were prospectively enrolled. Abbott AxSYM total and free PSA were measured by the same technician using the same instrument and the same reagent batch. RESULTS: Percent free PSA was more effective than total PSA in differential diagnosis between CaP and BPH in every evaluated dose range of total PSA. In cases with total PSA >4 microg/l, percent free PSA could have reduced by about 50% the rate of unnecessary biopsies with a probably still acceptable 93% cancer detection rate. The likelihood of CaP after the determination of percent free PSA was in fact higher than 50% using cut-off points which provide low sensitivity values (i.e. 58% in men aged 50-59 years). CONCLUSIONS: Percent free PSA is superior to total PSA in distinguishing primary CaP from BPH in patients with total PSA between 2 and 30 microg/l and in reducing the rate of unnecessary biopsies in men with total PSA higher than 4 microg/l. However, percent free PSA should be cautiously interpreted in decision making in individual patients since post-test probability is relatively low in men aged 50-70 years.

Aged↗

PubMed2000

Tension-free vaginal mesh repair for anterior vaginal wall prolapse.

OBJECTIVES: We determined the efficacy of the use of a tension free prolene mesh to correct a grade III anterior vaginal wall prolapse recurrence. METHODS: Twelve women (mean age 65.6 years) with stress urinary incontinence (SUI) (4 type II and 1 type III) and bladder prolapse entered the study. After vaginal incision a pretailored polypropylene mesh was fixed to its four angles by absorbable sutures to the urethropelvic ligaments and pubocervical fascia anteriorly and to the cardinal ligaments and pubocervical fascia posteriorly. When present, a posterior descensus was corrected during the same procedure. SUI was treated with the tension-free vaginal tape procedure (TVT) through a separate vaginal incision over the mid-urethra. RESULTS: All patients were available for postoperative pelvic examination at 3-month intervals, for a mean follow-up of 20.5 months (range 15-32). Nine patients were considered cured (no cystocele recurrence) while in 3 patients a grade 1 asymptomatic cystocele was present postoperatively (asymptomatic). No significant postoperative pain was reported by the patients. CONCLUSIONS: This study confirms that in patients with moderate cystocele a tension-free mesh to support bladder base and neck effectively treats the cystocele. It is particularly recommended in the treatment of previous failure with traditional techniques and when the quality of suspending tissue is poor or defective. A long-term study on a large number of patients is still warranted to confirm and validate its clinical use.

Aged↗

PubMed1999

Evaluation of morbidity of multi-channel pressure-flow studies.

This prospective study was carried out to evaluate the morbidity and complication rate of invasive urodynamics of the lower urinary tract after receiving oral antibiotic prophylactic treatment. A total of 105 patients, 55 men and 50 women, were included in the study and underwent pressure flow study (PFS) as part of the diagnostic assessment. Clinical diagnosis was prostatic obstruction from benign prostatic hyperplasia (BPH) in men and stress urinary incontinence or voiding dysfunction in women. Urine was screened for infection both before and after testing, and the incidence of urinary tract infections (UTI), dysuria, and other complications were assessed at 1-week follow-up to evaluate post-investigation morbidity. Dysuria of mild degree was experienced by 33% of patients, with no significant difference between male and female patients. Post-investigational UTI and fever were reported in 3.6% of men and 4% of women. Six patients had macroscopic hematuria of mild degree. No patient had urinary retention or severe complaints after the investigation and no patient required hospitalization. Post-void residual volume was higher in men with BPH obstruction compared to women; a significant difference between post-investigational UTI and residual volume could not be demonstrated (P = 0.8). We conclude that the objective morbidity rate of invasive urodynamic investigation is low. Mild dysuria is common, while severe complications, fever, and hematuria are seldom reported, and the risk of developing UTIs is low with antibiotic prophylaxis, with no significant difference between men and women. Neurourol. Urodynam. 18:647-652, 1999.

Adult↗

PubMed1999

Urodynamic analysis of voiding dysfunction in orthotopic ileal neobladder.

We examined the urodynamics, particularly voiding dysfunction, in patients with a neobladder. Free uroflowmetry, pressure-flow study, and voiding cystourethrography were performed in 22 patients (mean age 65 years) at a mean of 21 months after ileal neobladder substitution. The results of free uroflowmetry were used to divide patients into two groups: the good voiders and the poor. Daytime continence was achieved in all patients, while 10 (45%) had nighttime continence. To void 250 ml urine the good voiders strained 2 +/- 1.5 times, and the poor voiders 6 +/- 5 times. The neobladder neck was at the most caudal portion of the reservoir in good voiders, and there was wide funneling. In the group with poor emptying ability, the outlet was not located at the most dependent position. The principal factors for ensuring good voiding function in neobladder patients are the ability to perform effective straining and the location of the neobladder neck.

Adult↗

PubMed1998

Percent free prostate-specific antigen in assessing the probability of prostate cancer under optimal analytical conditions.

Although general consensus exists that percent free prostate-specific antigen (PSA) is superior to total immunoreactive PSA for prostate cancer (CaP) detection, its diagnostic performance is not yet well established. Analytical problems may account for difficulties in evaluating percent free PSA because the free PSA concentration is substantially lower than that of total PSA. The aim of the present study was to establish the diagnostic performances of the IMMULITE percent free PSA assay from Diagnostics Products Corp. under experimental conditions optimized to minimize analytical variability. Eighty-five patients with untreated primary CaP and 261 with untreated benign prostate hypertrophy (BPH) were prospectively enrolled. The Diagnostics Products IMMULITE total (Third Generation) and free PSA were measured by the same technician, using the same instrument and the same reagent batch. We calculated the post-test probability to express how the likelihood of the diagnosis of CaP changed after the percent free PSA was determined. Areas under the ROC curves of percent free PSA were better than those of total PSA in every evaluated range of total PSA. The percent free PSA could have reduced the rate of unnecessary biopsies by 47% in patients with total PSA >/=4 microg/L with only 3.8% false-negative results. The post-test probability of percent free PSA was, however, <50% in men 50-70 years of age, using cutoff points providing sensitivity from 99% to 80%. Percent free PSA is superior to total PSA in distinguishing primary CaP from BPH in patients with total PSA between 2 and 30 microg/L. In men with low total PSA, the diagnostic performance of the percent free PSA assay may be optimized by controlling methodological variability. The percent free PSA assay is effective in reducing the rate of unnecessary biopsies in men with total PSA >4 microg/L. However, the post-test probability provided by percent free PSA is relatively low in asymptomatic patients 50-70 years of age.

Aged↗

PubMed1997

Beta-endorphin and cortisol levels in plasma and CSF following acute experimental spinal traumas.

beta-endorphin and cortisol were measured in cerebrospinal fluid (CSF) and plasma by radioimmunological method (RIA) in two groups of rabbits with spinal cord traumatic injuries at cervical and lumbar levels, respectively with and without concomitant spinal shock and arterial hypotension, and in a group of sham operated animals as controls. The two groups with spinal lesions displayed a significant beta-endorphin increase in CSF, whereas the cortisol level remained unchanged both in the spinal traumatized rabbits and in controls. Both the opioid and the cortisol concentration rose significantly in plasma in all three groups and in particular resulted significantly higher in the cervical traumatized group where spinal trauma was associated with spinal shock and hypotension. However, no significant difference was found when beta-endorphin concentrations in plasma were compared between the sham operated animals and the spinal lumbar traumatized animals without concomitant spinal shock. The results seem to suggest that the beta-endorphin increase in CSF is related to the nervous tissue lesion, while its increase in plasma, like that of cortisol, is due to surgery or other stress factors inherent in the experiment. This independent behaviour of beta-endorphin in plasma and in CSF suggests its different origin in these two compartments.

Animals↗

PubMed1995

Cerebral and cerebellar diaschisis following carbamazepine therapy.

1. The regional cerebral blood flow was studied by SPECT in patients with partial epilepsy before and after 30 days of monotherapy with carbamazepine (CBZ). 2. Both a qualitative visual interpretation and a semiquantitative analysis of SPECT was performed. All patients underwent EEG, CT scan, and MRI studies. The CBZ serum concentrations were assayed. 3. After therapy, in three patients with focal epilepsy, both a crossed cerebral and cerebellar diaschisis were observed, with respect to the side of the epileptic focus in the opposite hemisphere. No morphologic changes were detected at MRI in the cerebral or cerebellar remote hypometabolic areas found at SPECT. 4. CBZ may have a depressant action on the corticopontocerebellar pathways and on the corticocallosal connections.

Adolescent↗

PubMed1995

How alternative are immunoassay systems employing non-radioisotopic labels? A comparative appraisal of their main analytical characteristics.

The immunoassay is one of the most sensitive and reliable analytical techniques available in the clinical laboratory. The original label for immunoassays was radioisotopes, and these methods, radioimmunoassay (RIA) and immunoradiometric assay (IRMA) are still the reference methods, because of invulnerability of the radioactive emission with respect to environmental interference. Labels other than radioisotopes have been tested for use in immunoassay to improve the sensitivity and reliability and to avoid some of the disadvantages of radioisotopic techniques. New labels have continued to be developed (Horseradish peroxidase-HPR-, pyrophosphatase, luciferases, pyrodopirazines, europium cryptates, porphirins, phosphors) and new label detection methods have been set up (e.g. chemiluminescence assay, thermometric assay, NADP+ and FADP- based coupled assay). New immunoassay strategies such as simultaneous multianalyte automated test have been developed and the reliability of the assays has in some cases caused division among researchers about the choice between the radioisotopic immunoassay or the non-radioisotopic immunoassay, as considerable effort and investment had been devoted to the search for more sensitive and practicable tests than the classic RIA-IRMA methods. The evolution of immunoassays (Monoclonal Antibodies, non-radioactive tracers, automation) has produced systems which allow a large number of laboratories to determine a great number of analytes with very good practicability. The availability of fully automated systems has generated the opinion that analytical performance of immunoassays can be considered similar to that of many traditional parameters of clinical chemistry. This conclusion seems however too optimistic, in fact data collected from interlaboratory studies demonstrate that problems concerning the analytical reliability of the measurements still remain not completely solved. In the authors' opinion, this opposition between immunological assay based on isotopic or non-isotopic labels is misleading, because each assay (whether it uses isotopic, enzymatic, fluorimetric or luminescent labels) has its own analytical characteristics and performance. For this reason the term "alternative", used to indicate all non-isotopic assays as a unique class of tests, should be abandoned. From a theoretical point of view the choice should not be between isotopic and non isotopic techniques. For each analyte to be tested, it is advisable to use the immunological assay that suits the requirements of the laboratory, irrespective of type of label. From a practical point of view, the choice should be based on the analytical performance and on the characteristics of each assay, on its cost and the type of instrumentation available in the laboratory, and on the experience and the knowledge of the laboratory personnel.

Costs and Cost Analysis↗