A pilot study evaluating 99mTc-anti-TNF-alpha scintigraphy in graves' ophtalmopathy patients with different clinical activity score.

The present study describes the preliminary results of the use of 99mTc-anti-TNF-α scintigraphy as a new diagnostic approach to evaluate patients presenting with Graves' ophthalmopathy (GO). Patients (n=25) presenting at different inflammatory stages of GO and 10 healthy volunteers underwent 99mTc-anti-TNF-α scintigraphy. Images were obtained 15 min after the intravenous injection of 370 MBq (10 mCi) 99mTc-anti-TNF-α. Planar images were obtained in a 256×256 matrix (each lasting 5 min) and single photon emission computed tomography (SPECT) scan lasting 13 min. Regions of interest (ROI) were drawn on the orbit and cerebral hemispheres. The uptake of 99m Tc-anti-TNF-α in these regions was compared and positive scintigraphy established when the ROI was >2.5. In addition, uptake for each positive exam was scored as either slight (2.6-5.1), moderate (5.2-7.6), or high (>7.6). In this pilot study, 69 orbits were evaluated (1 patient had only 1 eye), and 27 had a positive CAS (≥3/7). Scintigraphies were positive in 38 orbits. Comparing the results of the exams with CAS, a high sensitivity and negative predictive values were determined for scintigraphy (96.3% and 96.7%, respectively). However, the specificity and the positive predictive values were 71.4% and 68.4%, respectively, with an accuracy of 81.2%. The exclusion of examinations that were slightly positive from the analysis resulted in an improvement in test accuracy (95.5%). The preliminary results suggest that 99mTc-anti-TNF-α scintigraphy is a promising procedure for the evaluation of active orbital inflammation in GO.

Radioactive synovectomy with (90) yttrium and (153) samarium hydroxyapatite in haemophilic joints: preliminary study on radiation safety.

Most countries still do not achieve 1 IU of factor VIII/capita sufficient for survival. Although primary prophylaxis prevents synovitis, is not universally used. Chronic synovitis is treated with arthroscopy at expense of considerable amount of coagulation factors, and specialized surgeons. Radioactive synovectomy (RS) is a minimally invasive and cost effective alternative to arthroscopy, often considered first the option for persistent synovitis. Even without established causation with cancer, RS is avoided by some, due to this concern. We aim contributing to the understanding of RS safety regarding malignancy, presenting a large number of treated patients, and a single case of cancer. Three centres in Brazil applied RS with (90) Yttrium Citrate, (90) Yttrium hydroxyapatite or (153) Samarium hydroxyapatite in haemophilic joints and performed a survey addressing cancer in these patients. Four hundred and eighty eight patients (ages 3-51) received 1-3 RS (total 842) and follow-up was 6 months to 9 years. One patient aged 14 years presented Ewing sarcoma, 11 months after RS. The tumour was treated successfully with surgery and chemotherapy. Causality of cancer by RS is improbable in this case. Accordingly, latency here is far below minimum 5-10 years for radio-induction of solid tumours. Moreover, ES is not a typically radio-induced tumour, even at high doses. In agreement with others, though recognizing limitations, this study suggests RS is safe regarding cancer induction. Synovitis is a known burden for patients. The decision of making reasonable usage of RS should be outweighed with the risks of leaving synovitis untreated.

Protocatechuic acid alkyl esters: hydrophobicity as a determinant factor for inhibition of NADPH oxidase.

This study presents the increased efficiency of NADPH oxidase inhibition produced by esterification of protocatechuic acid (P0). Alkyl esters bearing chain lengths of 4 (P4), 7 (P7) and 10 (P10) carbons were synthesized and their oxidation potential, hydrophobicity, antiradical activity, inhibition of superoxide anion (O2°(-)), and the abilities to affect hypochlorous acid (HOCl) production by leukocytes and inhibit myeloperoxidase (MPO) chlorinating activity were studied. The increased hydrophobicity (logP, 0.81-4.82) of the esters was not correlated with a significant alteration in their oxidation potential (0.222-0.298 V). However, except for P10, the esters were ~ 2-fold more effective than the acid precursor for the scavenging of DPPH and peroxyl radicals. The esters were strong inhibitors of O2°(-) released by activated neutrophils (PMNs) and peripheral blood mononuclear cells (PBMCs). A correlation was found between the carbon chain length and the relative inhibitory potency. P7, the most active ester, was ~ 10-fold more efficient as NADPH oxidase inhibitor than apocynin. The esters strongly inhibited the release of HOCl by PMNs, which was a consequence of the inhibition of NADPH oxidase activity in these cells. In conclusion, as effective inhibitors of NADPH oxidase, the esters of protocatechuic acid are promising drugs for treatment of chronic inflammatory diseases. Moreover, this is the first demonstration that, besides the redox active moiety, the hydrophobicity can also be a determinant factor for the design of NADPH oxidase inhibitors.

9°Yttrium-hydroxyapatite: a new therapeutic option for radioactive synovectomy in haemophilic synovitis.

Recurrent haemarthroses often lead to chronic synovitis in patients with haemophilia and von Willebrand disease. Radioactive synovectomy with yttrium-90 (9°Y) citrate is frequently used to treat this complication, usually with good results. Since 2006, the Nuclear Energy Research Institute (IPEN, Sao Paulo, Brazil) has produced hydroxyapatite particles labelled with 9°Y for radioactive synovectomy. The aim of this study was to compare the results achieved by both forms of 9°Y in the treatment of haemophilic synovitis. We included 221 joints from 136 patients (age range: 6-20 years), treated by one of the two radiopharmaceuticals, at the Hemocenter of Mato Grosso, Brazil. The outcomes analysed were the annual frequency of haemarthrosis, articular pain and joint range of motion before and 1 year after RS. Similar results were achieved regardless of whether 9°Y hydroxyapatite or 9°Y citrate was used, and results were independent of the joint type, age, gender, radiologic stage and presence of inhibitors. 9°Y hydroxyapatite appears to be equivalent to the reference product 9°Y citrate in the treatment of chronic synovitis associated with bleeding disorders.

Bone marrow cell transplant does not prevent or reverse murine liver cirrhosis.

We tested the effect of bone marrow cell (BMC) transplantation in either preventing or reversing cirrhosis on an experimental model of chronic liver disease. Female Wistar rats were fed a liquid alcohol diet and received intraperitoneal injections of carbon tetrachloride (CCl4) over 15 weeks. Ten animals (cell-treated group) received five injections of BMCs during the cirrhosis induction protocol (on the 4th, 6th, 8th, 10th, and 12th weeks) and four animals received the cells after liver injury was established through tail vein. Nine animals (nontreated group) were submitted to the previously described protocols; however, they received vehicle injections. Analyses were performed to verify whether the infusion of cells was effective in preventing the development of cirrhosis in our model of induction, and if the cells could reverse cirrhosis once it was established. Hepatic architecture and fibrotic septa were analyzed in liver slices stained with hematoxilin & eosin and Sirius red, respectively. Fibrosis quantification was measured by Sirius red histomorphometry. Indirect immunofluorescence was performed to detect the amount of tissue transglutaminase 2. Blood analyses were performed to assess liver injury and function by the assessment of alanine aminotransferase and albumin. Ultrasound was performed to analyze the portal vein caliber and presence of ascitis. Cirrhosis features (regenerative nodules and fibrous septa) were observed in histopathology after 15 weeks of continuous hepatic injury in nontreated and cell-treated groups. Collagen content, immunofluorescence analysis, and biochemical and ultrasound parameters were similar in nontreated and cell-treated groups; however, both groups showed significant differences compared to a normal control group. Cell infusions with bone marrow-derived cells seem to be ineffective in improving morphofunctional parameters of the liver when applied to chronic cases either during or after establishment of the hepatic lesion.

Monitoring rheumatoid arthritis synovitis with 99mTc-anti-CD3.

The aim of this study was to investigate the feasibility of using a monoclonal antibody (OKT3) labelled with technetium-99m (99mTc) to monitor disease activity in patients with rheumatoid arthritis. We evaluated 38 patients who were diagnosed with rheumatoid arthritis and classified as Classes II and III after functional assessment (according to the revised criteria specified by the American College of Rheumatology). Two sets of planar anterior images of the patients' wrists, metacarpophalangeal and interphalangeal joints, elbows, shoulders and knees joints were obtained 1 h and 3 h after the injection of 99mTc-OKT3. The scintigraphic findings showed significant correlation (p<0.05) between the radiopharmaceutical accumulation of 99mTc-OKT3 and swollen joints, tender joints and the visual analogue scale. They were able to differentiate patients in remission from patients with active synovitis, according to DAS 28. In contrast, there was no correlation between the radiopharmaceutical accumulation and the patients' age, gender, duration of disease or erythrocyte sedimentation rate. A relatively high disease activity score of 28 joints (4.08+/-1.74) was found in the majority of patients. In conclusion, 99mTc-OKT3 scintigraphy is a reliable and objective method for detecting synovial activity, and can be used to observe disease prognosis.

Radioguided occult lesion localization (ROLL) and excision of breast lesions using technetium-99m-macroaggregate albumin and air injection control.

The aim of this study was to assess the efficiency of the radioguided localization and excision technique using radiopharmaceuticals injected directly or close to occult breast lesions. We studied thirty-two consecutive patients with thirty-six occult breast lesions detected mammographically or ultrasonically categorized as BI-RADS 3, 4 or 5. Macroaggregate Albumin (MAA) labeled with (99m)Tc was administered directly or close to the lesion, guided by mammography or ultrasound, followed by an air injection for radiological control. The excision biopsy was carried out with the aid of a hand-held gamma detecting probe and the entire removal of the lesion was verified by X-ray of the surgical specimens or by intraoperatory frozen section examination. Breast cancer was found in 8.3% of BI-RADS 3 lesions, in 33.3% of the BI-RADS 4 lesions and in 66.6% of the BI-RADS 5 lesions. The radiotracer was correctly positioned in 97.2% of the specimens (35/36) allowing the removal of 97.2%. Xray confirmed the entire removal in 27 lesions (75%), intraoperatory frozen section study in 19.4% (7/36) and by both methods in 5.5% (2/36). Radioguided surgery turned out to be an important tool in the removal of non-palpable breast lesions, as a simple, fast and feasible method that can be implemented in the clinical routine of patients with non-palpable breast lesions.

Failure predictors of the sentinel lymph node in patients with breast cancer using Tc-99m sulfur colloid and periareolar injection.

AIM: As sentinel lymph node (SLN) experience rises, it is important to identify factors that can limit lymphoscintigraphic mapping. METHODS: A prospective study was conducted with breast cancer patients that were submitted to sentinel node mapping by lymphoscintigraphy between October 2003 and January 2005. The analyzed factors were: patients' age, body mass index, tumor size, previous breast surgeries, time between a previous biopsy and the radiotracer injection and their impact on preoperative SLN identification. RESULTS: Two hundred and three breast cancer patients were injected with (99m)Technetium-sulfur colloid and submitted to lymphoscintigraphy scan for SLN biopsy. One hundred and eighty-four of these patients (90.64%) had a successfully identified SLN and 19 (9.36%) had a mapping failure. The median age of the successful group was 55.6 years and in the failure group was 57.1 years (P=0.002). The median body mass index was 25.3 and 27.6, respectively (P=0.024). The tumor size did not show any significant difference between the patients with successful mapping and failure (P=0.07). Previous breast surgery was an important limiting factor for SLN mapping (P=0.017). The mean time from biopsy to SLN detection was 23.6 days on the successfully marked patients and 17.4 days in the failure group (P<0.0001). All the 184 successfully mapped patients had the SLN identified. Only one patient of the failure group had the SLN identified using blue dye. CONCLUSION: Advanced age, elevated body mass index, previous breast surgery and a shorter period of time after a breast biopsy are causes for SLN identification failure. The tumor size was not a limiting factor.

Sentinel node identification by scintigraphic methods in cutaneous melanoma.

In melanoma patients lymph node metastasis is an important prognostic factor that indicates the need for therapeutic lymph node dissection. Preoperative lymphoscintigraphy mapping associated with radioguided sentinel lymph node biopsy has become a well established procedure for cutaneous melanoma patients without clinically detectable lymph node metastases (stage I, II). This technique is a versatile way of characterizing the lymphatic basin at risk for metastases and identifying involved lymph nodes. The purpose of the present study was to examine the reproducibility of lymphoscintigraphy and sentinel lymph node biopsy in detecting micro metastases in cutaneous melanoma. The study was a single-institution prospective analysis of 74 melanoma patients, with primary tumors having Breslow thickness > 0.7 mm, who underwent lymphoscintigraphies between May 2002 and September 2003. Technetium-99m sulfur colloid was injected intradermally at the primary tumor site and dynamic images were obtained for 40 minutes. Two observers evaluated the images. One to two weeks after the first lymphoscintigraphy, radioguided lymph node biopsy was performed. For the biopsy, technetium-99m sulfer colloid was injected intradermally in the same manner as performed before. Lymph nodes were identified and removed with the aid of a gamma ray detecting probe (GDP), and were submitted to histopathological analysis. The histopathological analysis of the sentinel lymph nodes collected during surgery was performed in a sequential manner. First, frozen sections were analyzed during surgery. The lymph nodes considered negative by frozen section were analyzed by H&E staining. Subsequently, the slides considered negative with H&E were sent for immunohistochemical analysis. Lymphoscintigraphy identified at least one sentinel lymph node in all patients. Sentinel node biopsy detected metastases in 20 patients (27.2%). In all cases the lymph node basins identified during lymphoscintigraphy were found to have at least one sentinel lymph node during surgery. Frozen section analysis of the lymph node was only able to identify the disease in 35% of the patients eventually found to have micrometastases with H&E and immunohistochemistry. Two lymph nodes were negative with H&E and positive with immunohistochemical analysis. In conclusion, lymphoscintigraphy is a simple procedure that is well tolerated by patients. It is useful in locating sentinel lymph nodes in patients with melanoma and is an important tool in the clinical practice of oncology. We recommend performing H&E, and if necessary, immunohistochemical analysis of all sentinel lymph nodes because of the high rate of false negative results with frozen sections alone.

Identification of sentinel node in breast cancer: comparison between peritumoral and periareolar injection of the radiopharmaceutical contrast medium.

Axillary node status is the most important prognostic factor for patients with primary breast carcinoma. The sentinel node biopsy (SN) technique has received much attention as a possible alternative to axillary lymph node dissection. The aim of this study is to identify the sentinel node by periareolar and subdermal injection of the radiopharmaceutical in four points, independent of tumor topography and the presence of biopsies and/or previous surgery. The peritumoral injection technique was carried out for comparison purposes. This study was performed on 115 patients, divided into 2 groups: Group A (25 patients, peritumoral injection) and Group B (90 patients, injection in four points). All the SN biopsies were studied by both imprint cytology and H&E staining. Control axillary lymph-node dissection was followed in all patients from Group A and in these positive cases from Group B. Twenty-two out of the twenty-five (88%) SNs were identified in Group A. There was no false negative; the sensitivity and specificity were 100%. Eighty-two of the ninety (91.1%) SNs were identified in Group B. Lymphoscintigraphy showed radiopharmaceutical migration to axilla in 93.7% of the cases. Hotspot area was 10 to 100 times the intensity of the background radiation. Among the 92 cases with negative sentinel nodes at intraoperative examination (TP), the SN histopathology confirmed the absence of cancer cells in 89 patients, whereas 3 were positive for metastatic cells. This study shows that periareolar injection in four points seems to be a good lymphatic mapping method for SN identification. We suggest standardizing this site of injection to identify the SNs. More studies to confirm these findings are ongoing.

Diagnosis of renal allograft rejection and acute tubular necrosis by 99mTc-mononuclear leukocyte imaging.

One hundred kidney transplant recipients were evaluated on the first and fifth days after transplantation by Tc-99m mononuclear cell scintigraphy. We have developed a quantitative method to diagnose rejection and acute tubular necrosis (ATN) by comparing regions of interest drawn on allograft scintigraphs at different times after endovenous administration of the labeled cells. We suggest that the use of Tc-99m-WBC may be useful for the early diagnosis of rejection and the differential diagnosis of ATN.

Identification of sentinel node in breast cancer.

Axillary lymphadenectomy is a very important procedure in the staging of breast cancer patients. However, it is associated with a significant morbidity rate. On the other hand, using early diagnosis we can see a high number of cases where the lymph nodes are negatives. With the intention of avoiding unnecessary axillary dissection, the possibility of evaluating a single node has been studied. This lymph node, defined as "sentinel node", would be the first to receive tumoral lymphatic drainage. The aim of this study is to evaluate: (i) the efficacy of the methods to identify the sentinel nodes, (ii) estimate the predictability of the histological examination of the sentinel node in comparison to other nodes of the axilla, (iii) compare the efficacy of the frozen section regarding the definitive histological examination of the same node. This study was performed in 29 patients, and the sentinel node was identified in all of them. It was metastatic in 7 (24.1%). Out of the 22 patients where the node was negative, 15 were submitted to complete dissection. Out of these 15, there was one case (6.7%) where one lymph node of the first level was positive. All 7 patients with the positive sentinel node were submitted to axillary dissection. When comparing the histological examination of the sentinel node with other nodes, we got a sensitivity of 87.5%, specificity of 100%, predictive positive value of 100%, predictive negative value of 93% and efficacy of 95%. The intra-operative examination was made in 24/29 cases (82.7%). The correlation between both examinations was 95.8%. This study shows that the technique of the sentinel node will be a reliable method to avoid radical axillary dissection in breast cancer patients with early diagnosis.

Selective activity of butyrylcholinesterase in serum by a chemiluminescent assay.

In a previous study, we showed that purified commercial esterase activity can be detected in a chemiluminescent assay based on the hydrolysis of 2-methyl-1-propenylbenzoate (MPB) to 2-methyl-1-propenol, which is subsequently oxidized by the horseradish peroxidase (HRP)-H(2)O(2) system. The purpose of this study was to verify the applicability of this assay to human serum. The existence of an esterase activity capable of hydrolysing MPB is indicated by the fact that the MPB-serum-HRP-H(2)O(2) system consumes oxygen and emits light. Both signals were abolished by prior serum heat inactivation and were preserved when serum was stored at < or =4 degrees C. Addition of aliesterase inhibitors, such as fluoride ion and trichlorfon or the cholinesterase inhibitor eserine, totally prevents light emission. The butyrylcholinesterase-specific substrate benzoylcholine causes a delay in both O(2) uptake and light emission, while the specific acetylcholinesterase substrate, acetyl-beta-methylcholine, had practically no effect. Purified butyrylcholinesterase, but not acetylcholinesterase, triggered light emission. The finding that butyrylcholinesterase is responsible for the hydrolysis of MPB in serum should serve as the basis for the development of a specific chemiluminescent assay for this enzyme.

Tc-99m-leukocytes--is it an intracellular labelling?

Radiolabeled leukocytes have a potential for clinical use in detecting sites of inflammation. The increasing interest in the use of Tc-99m-labeled white blood cells (WBC) encourages exploration into the site(s) of binding of Tc-99m to the WBC components. Here we present the differential centrifugation study of the labeled leukocytes using a simple and low cost technique (SnTec). The results show most part of radioactivity bound to cytosol. We concluded that this is an intracellular labeling procedure that has the citoplasm, ribosomes unbound to membrane and soluble molecules as targets.

Chemiluminescent determination of esterases in monocytes.

Esterase from monocytes promotes the hydrolysis of 2-methyl-1-propenylbenzoate (MPB) yielding 2-methyl-1-propenol, which is oxidized by horseradish peroxidase/H2O2 producing triplet acetone. The chemiluminescence of this reaction can be enhanced by the addition of 9,10-dibromoanthracene-2-sulphonate. The non-specific esterase present in monocytes is responsible for MPB hydrolysis, since (a) the chemiluminescence of the reaction was inhibited by fluoride, and (b) cells that do not contain a significant amount of non-specific esterases, e.g. lymphocytes and neutrophils, did not trigger light emission. The analytical application of this reaction is considered.

Influence of tobacco on the labelling of red blood cells and plasma proteins with technetium-99m.

Technetium-99m-labelled red blood cells (RBC) have been used as radiopharmaceutical in nuclear medicine. The influence of drug interaction in this labelling process has been described along with the biological effects of tobacco on the labelling of blood elements with technetium-99m. The labelling of RBC and plasma proteins can be decreased in presence of tobacco. This can be due to either a direct or indirect effect (reactive oxygen species) of tobacco by (i) oxidation of the stannous ion, (ii) possible damages caused in plasma membrane and/or (iii) possible chelating action on the stannous and/or pertechnetate ions.

Evaluation of 99mtechnetium-radiopharmaceutical binding to blood elements using different trichloroacetic acid concentrations.

Secure determination of the binding of 99mTc-radiopharmaceuticals to plasma (P) and blood cell (BC) constituents can help to understand the biodistribution of radiophamaceuticals. The reported precipitation studies of blood with radiopharmaceuticals have shown that the results can not be easily compared between studies. We decided to determine the "gold standard" concentration of trichloroacetic acid (TCA) to evaluate the binding to blood elements for several radiopharmaceuticals used in routine nuclear medicine. We have studied phytic (99mTc-PHY), diethylenetriaminepentaacetic (99mTc-DTPA), glucoheptonic (99mTc-GHA) and dimercaptosuccinic (99mTc-DMSA) acids. Blood was incubated with radiopharmaceuticals, centrifuged and P and BC separated. Samples of P and BC were also precipitated with TCA concentrations (20.0, 10.0, 5.0, 1.0, 0.5 and 0.1 percent) and soluble (SF) and insoluble fractions (IF) were isolated. The percent radioactivity (percent rad) in IF-P depends on TCA concentration. It varied from 36.4 to 65.0 (99mTc-PHY), from 17.9 to 32.0 (99mTc-DTPA), from 11.5 to 38.8 (99mTc-GHA) and from 52.8 to 66.2 (99mTc-DMSA). The results for the binding of 99mTc-PHY to IF-P show that there was no differences in the percent rad when TCA concentrations of 0.1 to 1.0 percent were used. For 99mTc-DTPA, 5.0 percent is the best TCA concentration. For 99mTc-GHA, low values of percent rad bound to IF-P is found with TCA concentrations of 0.1, 0.5 and 1.0. Interestingly, with 99mTc-DMSA, high values of bound radioactivity are not dependent on TCA concentrations (0.1 to 10.0). Radioactivity in IF-BC depends on TCA concentration and it varied for 99mTc-PHY (80.1 to 54.1) and for 99mTc-GHA (85.5 to 61.7). With 99mTc-DTPA and with 99mTc-DMSA the percent rad in IF-BC seems independent of TCA concentration. We suggest that the evaluation of the binding of the various 99mTc-radiopharmaceuticals to blood constituents, using only one TCA concentration, should be avoided.

Effect of cyclophosphamide on the binding of 99mTcO-4 and 99mTc-MDP to blood cells and plasma proteins.

Since the introduction of technetium-99m (99mTc) and its rapid acceptance as a tool in nuclear medicine, very little information is available about its biological action as 99mTc-radiopharmaceuticals. We have determined if cyclophosphamide, an alkylating agent, used in oncology as a chemotherapeutic drug, modifies the binding of 99mTcO-4 and 99mTc-MDP (99mTc-methylenediphosphonic acid) to blood cells and to plasma proteins. The radiopharmaceuticals were injected intravenously (iv) into SW-55 mice (male and female, weight 25 g) and samples of plasma and blood cells were separated. Cyclophosphamide (50 micrograms) was injected iv 1 h before the radiopharmaceuticals. Samples of plasma and blood cells were also precipitated with 5% trichloroacetic acid and soluble and insoluble fractions were isolated. The following results were obtained: 1) cyclophosphamide did not alter (0.25 to 8 h) percent radioactivity of 99mTcO-4 in plasma or blood cells but increased the binding of 99mTc-MDP to blood cells; 2) cyclophosphamide did not alter (0.25 to 8 h) the binding of 99mTcO-4 in insoluble fraction of plasma and decreased (1 to 4 h) percent radioactivity of 99mTc-MDP in the insoluble fraction of plasma; 3) cyclophosphamide increased (0.25 to 4 h) percent radioactivity of 99mTcO-4 in the insoluble fraction of blood cells but did not alter the binding of 99mTc-MDP. Cyclophosphamide and/or its metabolites modified the effective half-life of these radiopharmaceuticals (to 99mTcO-4 was increased 2.3 to 3.4 h and to 99mTc-MDP was decreased 3.3 to 2.1 h) and possibly increased the permeability of blood cells to 99mTcO-4.

Characterization of myeloid or lymphoid acute leukemia by a chemiluminescence assay. Comparison with immunocytochemistry using an antimyeloperoxidase antibody.

A simple and sensitive chemiluminescence assay for the demonstration of the activity of intracellular myeloperoxidase (MPO) is described, which is useful for the distinction between myeloid and lymphoid commitment in blasts from acute leukemia patients. When the cut-off point was settled at 13 mV of chemiluminescence all cases of acute myeloid leukemia (AML) were distinguished from those of acute lymphoid leukemia. In addition, this technique was able to demonstrate MPO activity in AML poorly differentiated (FAB-M0) which usually does not stain for MPO in classical cytochemistry preparations and could be negative also by immunocytochemistry with anti-MPO monoclonal antibody. Therefore the method here described presented a higher sensitivity than the immunocytochemistry procedure with anti-MPO.

[Dynamic scintigraphy of the esophagus--a method for esophageal dysfunction]. / Cintilografia dinâmica do esôfago--um método para disfunção esofagiana.

The authors present their experience with radionuclide transit in the study of esophageal motility using a very simple and easy technique. They have established a normal pattern and analyse their findings in achalasia and probable diffuse esophageal spasm. They review the literature and submit the method as a very important tool for the diagnosis of esophageal motor disorders.