Comparison of protocols with respiratory-gated (4D) motion compensation in PET/CT: open-source package for quantification of phantom image quality

BACKGROUND

Patient's breathing affects the quality of chest images acquired with positron emission tomography/computed tomography (PET/CT) studies. Movement correction is required to optimize PET quantification in clinical settings. We present a reproducible methodology to compare the impact of different movement compensation protocols on PET image quality. Static phantom images were set as reference values, and recovery coefficients (RCs) were calculated from motion compensated images for the phantoms in respiratory movement. Image quality was evaluated in terms of: (1) volume accuracy (VA) with the NEMA phantom; (2) concentration accuracy (CA) by six refillable inserts within the electron density CIRS phantom; and (3) spatial resolution (R) with the Jaszczak phantom. Three different respiratory patterns were applied to the phantoms. We developed an open-source package to automatically analyze VA, CA and R. We compared 10 different movement compensation protocols available in the Philips Gemini TF-64 PET/CT (4-, 6-, 8- and 10-time bins, 20%-, 30%-, 40%-window width in Inhale and Exhale).

RESULTS

The homemade package provided RC values for VA, CA and R of 102 PET images in less than 5 min. Results of the comparison of the 10 different protocols demonstrated the feasibility of the proposed method for quantifying the variations observed qualitatively. Overall, prospective protocols showed better motion compensation than retrospective. The best performance was obtained for the protocol Exhale 30% (0.3 s after maximum Exhale position and window width of 30%) with RC[Formula: see text], RC[Formula: see text] and RC[Formula: see text]. Among retrospective protocols, 8 Phase protocol showed the best performance.

CONCLUSION

We provided an open-source package able to automatically evaluate the impact of motion compensation methods on PET image quality. A setup based on commonly available experimental phantoms is recommended. Its application for the comparison of 10 time-based approaches showed that Exhale 30% protocol had the best performance. The proposed framework is not specific to the phantoms and protocols presented on this study.

Ultrastaging protocol in sentinel lymph node for apparent early stage ovarian cancer

OBJECTIVE

The objective of the present study is to determine the role of sentinel lymph node (SLN) ultrastaging in apparent early-stage ovarian cancer.

METHODS

We previously demonstrated the feasibility of SLN in early-stage ovarian cancer in a pilot study and in a clinical trial (NCT03452982). The SLN of the 30 patients involved in both were processed following an ultrastaging protocol. The cost of ultrastaging processing was also reported.

RESULTS

A SLN was detected in up to 91.3% and 90% in the pelvic and para-aortic region, respectively. In all cases, a SLN was detected at least in one field, pelvic or para-aortic. The mean time from injection to SLN resection was 53.3 ± 20.3 min. Two of 30 (6.6%) patients had a contralateral SLN in the para-aortic field, but no patients had contralateral SLN within the pelvic field after injection. The mean number of harvested SLN was 2.1 ± 1.4 (range: 0-5) and 2.7 ± 1.5 (range: 0-7) in the pelvic and para-aortic region, respectively. Two patients were upgraded to stage IIIA1 because of lymph node metastasis. In the first case, based on single sections and haematoxylin and eosin (H&E) examination, a pelvic SLN micrometastasis (1 mm) was found on the first H&E section. By using the ultrastaging protocol, the size of the metastasis was increased to 2.1 mm (macrometastasis). In the same patient, the ultrastaging study of the inframesenteric para-cava SLNs found isolated tumour cells in the subcapsular and interfollicular lymph nodes sinus in one of the two SLN harvested (in one of the sections at the fourth and fifth ultrastage levels). The other upstaged case was a para-aortic macrometastasis in a patient in whom the SLN was not identified in the para-aortic field because of the absence of migration from the infundibulo-pelvic stump injection. The cost of ultrastaging in each patient depended on the total number of SLN retrieved, averaging 96.8 € (range: 0-230.5) and 124.5 € (range: 0-322.7€) for pelvic and para-aortic SLN, respectively.

CONCLUSIONS

A uniform protocol for ultrastaging is essential for lower-volume metastasis detection and to provide reproducible information between upcoming studies, as evidence about SLN in ovarian cancer is growing.

Prevention and Management of Hormonal Crisis during Theragnosis with LU-DOTA-TATE in Neuroendocrine Tumors. A Systematic Review and Approach Proposal

Neuroendocrine tumors (NETs) frequently overexpress somatostatin receptors (SSTR) on their cell surface. The first-line pharmacological treatment for inoperable metastatic functioning well-differentiated NETs are somatostatin analogs. On second line, Lu-DOTA-TATE (177Lu-DOTA0 Tyr 3 octreotate) has shown stabilization of the disease and an increase in progression free survival, as well as effectiveness in controlling symptoms and increasing quality of life. The management of functional NETs before and during LU-DOTA-TATE treatment is specially challenging, as several complications such as severe carcinoid and catecholamine crisis have been described. The aim of this review is to establish practical guidance for the management and prevention of the most common hormonal crises during radionuclide treatment with Lu-DOTA-TATE: carcinoid syndrome (CS) and catecholamine hypersecretion, as well as to provide a brief commentary on other infrequent metabolic complications. To establish a practical approach, a systematic review was performed. This systematic review was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and conducted using MEDLINE (accessed from PubMed), Google Scholar and ClinicalTrials.gov. Literature searches found 449 citations, and finally nine were considered for this systematic review.

Pilot performance of a dedicated prostate PET suitable for diagnosis and biopsy guidance

Background

Prostate cancer (PCa) represents one of the most common types of cancers facing the male population. Nowadays, to confirm PCa, systematic or multiparametric MRI-targeted transrectal or transperineal biopsies of the prostate are required. However, due to the lack of an accurate imaging technique capable to precisely locate cancerous cells in the prostate, ultrasound biopsies sample random parts of the prostate and, therefore, it is possible to miss regions where those cancerous cells are present. In spite of the improvement with multiparametric MRI, the low reproducibility of its reading undermines the specificity of the method. Recent development of prostate-specific radiotracers has grown the interest on using positron emission tomography (PET) scanners for this purpose, but technological improvements are still required (current scanners have resolutions in the range of 4–5 mm).

Results

The main goal of this work is to improve state-of-the-art PCa imaging and diagnosis. We have focused our efforts on the design of a novel prostate-dedicated PET scanner, named ProsPET. This system has small scanner dimensions defined by a ring of just 41 cm inner diameter. In this work, we report the design, implementation, and evaluation (both through simulations and real data) of the ProsPET scanner. We have been able to achieve < 2 mm resolution in reconstructed images and high sensitivity. In addition, we have included a comparison with the Philips Gemini-TF scanner, which is used for routine imaging of PCa patients. The ProsPET exhibits better contrast, especially for rod sizes as small as 4.5 mm in diameter. Finally, we also show the first reconstructed image of a PCa patient acquired with the ProsPET.

Conclusions

We have designed and built a prostate specific PET system, with a small footprint and improved spatial resolution when compared to conventional whole-body PET scanners. The gamma ray impact within each detector block includes accurate DOI determination, correcting for the parallax error. The potential role of combined organ-dedicated prostate-specific membrane antigen (PSMA) PET and ultrasound devices, as a prebiopsy diagnostic tool, could be used to guide sampling of the most aggressive sites in the prostate.

Sentinel lymph node technique in early-stage ovarian cancer (SENTOV): a phase II clinical trial

Objective

Early-stage ovarian cancer might represent an ideal disease scenario for sentinel lymph node application. Nevertheless, the published experience seems to be limited. Our objective was to assess the feasibility and safety concerns of sentinel lymph node biopsy in patients with clinical stage I–II ovarian cancer.

Methods

We conducted a prospective cohort study of 20 patients with histologically confirmed ovarian cancer. ^99mTc and indocyanine green were injected into both the utero-ovarian and infundibulopelvic ligament stump, if they were present, during surgical staging. An intraoperative gamma probe and near-infrared fluorescence imaging were used to detect the sentinel lymph nodes. Inclusion criteria included: >18 years of age, suspicious adnexal mass (unilateral or bilateral) at ultrasound and CT imaging or confirmed ovarian tumor after previous surgery (unilateral or bilateral salpingo-oophorectomy with or without hysterectomy). Adverse events were recorded through postoperative day 30. The primary trial end point was to report adverse events related to the technique, including the use of ^99mTc and ICG intraperitoneally, as well as the feasibility of the technique.

Results

A total of 20 patients were included in the analysis. Sentinel lymph nodes were detected in 14/15 (93%) pelvic and all 20 (100%) para-aortic regions. Five patients did not have utero-ovarian injection because of prior hysterectomy. The mean time from injection to sentinel lymph node resection was 53±15 min (range; 30–80). The mean number of harvested sentinel lymph nodes was 2.2±1.5 (range; 0–5) lymph nodes in the pelvis and 3.3±1.8 (range; 1–7) lymph nodes in the para-aortic region. There were no adverse intraoperative events, nor any within the 30 days of follow-up related with the technique.

Conclusion

Sentinel lymph node mapping in early-stage ovarian cancer is feasible without major intraoperative or < 30 days safety concerns. (NCT03452982).

Trial registration number

ClinicalTrials.gov, NCT03452982.

Sentinel Lymph Node Technique in Apparent Early Ovarian Cancer: Laparoscopic Technique

STUDY OBJECTIVE

To demonstrate the feasibility of laparoscopic sentinel lymph node technique in presumed early-stage ovarian cancer.

DESIGN

Video illustrating the laparoscopic performance of the sentinel lymph node technique in ovarian cancer.

SETTING

The Oncologic Gynecology Department at the University Hospital La Fe.

PATIENTS

Candidates for the technique presented an apparent early stage ovarian cancer. The technique was performed in the context of a clinical trial called SENTOV (NCT03452982).

INTERVENTIONS

To date, lymphadenectomy is recommended after the diagnosis of apparent early-stage ovarian cancer as part of the surgical staging. Minimally invasive surgery can be considered for the purpose of restaging [1]. Up to 14% of the patients are upstaged because of positive lymph nodes after pelvic and para-aortic lymphadenectomy [2]. Regarding low-grade tumors, a lower rate of lymph node involvement has been reported [3]. Sentinel lymph node technique has been reported to be feasible in a recent pilot study [4]. Two clinical trials (Sentinel Lymph Node in Early Ovarian Cancer and Sentine Lymph Node in Early Ovarian Cancer) are currently ongoing to clarify the use of sentinel lymph node technique in early ovarian cancer. The injection points were at the infundibulopelvic and ovarian ligament stumps. Two hundred microliters of saline solution containing 37 MBq of technetium-99m nanocolloid followed by 0.5 mL of indocyanine green (ICG) was injected subperitoneally. We used a 27 G needle at each injection point. Immediately after injection and also at 15 and 30 minutes after injection, the operative field was checked guided by the acoustic signal of the gamma probe and the near-infrared camera. We performed a minimum dissection looking for the sentinel lymph node or nodes in the pelvic and para-aortic region. Any lymph node with a remarkable radioactivity count as high as 10 times the background and/or dyed with ICG was considered a sentinel lymph node and was harvested separately. A systematic surgical staging was performed after the sentinel lymph node procedure was completed. Because of its small size, the ICG molecule is not caught in the lymph node valve system and keeps migrating when performing lymphography. An exhaustive direct view of the dye path is required to avoid misleading detection of the real sentinel lymph node. This theoretical problem is resolved by the use of the 99mTC-nanocolloid. This tracer gets trapped into the lymph node valve system because of its molecular size and does not keep migrating as does ICG. As such, a combination of both methods is proposed.

CONCLUSION

Laparoscopic performance of sentinel lymph node technique in ovarian cancer seems to achievable. Between 2017 and 2019, this procedure was performed in 30 patients (13 laparoscopic), in the context of our pilot experience [4] and the Sentinel Lymph Node in Early Ovarian Cancer clinical trial (NCT03452982).

Clinical application of the sentinel lymph node technique in early ovarian cancer: a pilot study

Introduction

There is limited evidence favoring the use of the sentinel lymph node technique in ovarian cancer, and no standardized approach has been studied. The objective of the present pilot study is to determine the feasibility of the sentinel lymph node technique by applying a clinical algorithm.

Methods

Patients with confirmed ovarian cancer were included. 99mTc and indocyanine green were injected into the ovarian and infundubulo-pelvic ligament stump. A gamma probe and near-infrared fluorescence imaging were used for sentinel lymph node detection.

Results

The sentinel lymph node technique was performed in ten patients with a detection rate in the pelvic and/or para-aortic region of 100%. The tracer distribution rates of sentinel lymph nodes in the pelvic and para-aortic regions were 87.5% and 70%, respectively.

Conclusion

The detection of sentinel lymph nodes in early-stage ovarian cancer appears to be achievable. Based on these results, a clinical trial entitled SENTOV (SENtinel lymph node Technique in OVarian cancer) will be performed.

Successful Second-Line Metronomic Temozolomide in Metastatic Paraganglioma: Case Reports and Review of the Literature

Metastatic pheochromocytoma and paraganglioma (mPHEO/PGL) are frequently associated with succinate dehydrogenase B (SDHB) mutations. Cyclophosphamide-dacarbazine-vincristine (CVD) regimen is recommended as standard chemotherapy for advanced mPHEO/PGL. There is limited evidence to support the role of metronomic schemes (MS) of chemotherapy in mPHEO/PGL treatment. We report 2 patients with SDHB-related mPGL who received a regimen consisting of MS temozolomide (TMZ) and high-dose lanreotide after progression on both CVD chemotherapy and high-dose lanreotide. Molecular profiling of the tumor tissue from both patients revealed hypermethylation of the O6-methylguanine-DNA-methyltransferase (MGMT) promoter. In one patient, progression-free survival was 13 months and the second patient remained under treatment after 27 months of stabilization of metabolic response of his disease. Treatment was well tolerated, and adverse effects were virtually absent. A modification in the scheme of TMZ from standard schemes to MS is safe and feasible and can be considered in patients with progressive mPHEO/PGL refractory to dacarbazine in standard doses.

177Lu-DOTATATE treatment in neuroendocrine tumours. A preliminary study

Therapy with radiolabelled somatostatin analogue peptides is a promising new therapy to treat neuroendocrine tumours. The aim of this preliminary study is to present our experience with ¹⁷⁷Lu-DOTATATE therapy, and evaluate tolerability and short-term efficacy in patients with tumours expressing somatostatin receptors. A total of 7 patients with metastatic neuroendocrine tumours were treated, each with 4 doses of ¹⁷⁷Lu-DOTATATE. The treatment response was evaluated in the form of biochemical response (tumour markers), imaging methods (somatostatin receptor scintigraphy, computed tomography, and magnetic resonance), and functional and quality of life responses using the Karnofsky performance status scale. Treatment toxicity was also evaluated. The results obtained were as follows: Biochemical response: 60% of patients showed tumour marker levels returning to normal, while they decreased significantly in the remaining 40%. Imaging response: 85.7% had a partial response, while 14.3% showed stable disease. All (100%) patients showed a significant improvement in quality of life, with increased Karnofsky scale scores. No patient had acute or chronic toxicity, and subacute transient haematological toxicity was observed in 42.8% of patients. Despite being a preliminary study, it was found that treatment with ¹⁷⁷Lu-DOTATATE is a safe treatment with few side effects, and an objective response was achieved in most patients.

Individualised dosimetry in patients with differentiated thyroid cancer based on external dose-rate. Optimisation of the number of measurements

OBJECTIVES

To compare the results of individual dosimetry in differentiated thyroid cancer patients treated with (131)I at our centre with the established limits and dosimetry results of published studies. Analysis of the optimal number of measurements necessary to reduce the impact of dosimetry for the comfort of the patient and, secondly, on the workload of health workers.

MATERIAL AND METHODS

Dosimetry was performed in the Nuclear Medicine Department of the University and Polytechnic Hospital La Fe, on 29 patients suffering from differentiated thyroid cancer and treated with activities between 1.02 and 5.51 GBq (mean 2.68 GBq) of (131)I. The Spanish Society of Medical Physics (SEFM) protocol was used, based on measurements of external dose rate adjusted to a bi-exponential curve according to a two compartment model. Different dosimetries were performed on each patient, taking different selections of the available measurements in order to find the optimal number.

RESULTS

Results are well below the dosimetry limits, and are consistent with those obtained in other centres. The number of measurements can be reduced from 5, as proposed in the SEFM protocol, to 4 without significant loss of accuracy. Further reducing measures may be justified in individual cases.

CONCLUSIONS

The values obtained for the dosimetry quantities are significantly below the established limits. A reduction in measurements can be assumed at the cost of a moderate increase in uncertainty, benefiting the patient.

Hemoperfusion in diabetic coma

Hemoperfusion on ionic exchange resins in the therapy of diabetic keto-acidosis (DKA) coma is proposed. Resins used are strong anionic resins in mixed form able to release bicarbonates and to trap ketoanions and organic anions in a stoichiometric manner. A series of trials in open circuit are performed in order to search for a suitable mixture of resins and to establish the amounts of HCO3- and ketoanions respectively released or entrapped. Therefore, ten simulated hemoperfusions in closed circuit systems were performed, utilizing cartridges containing 1,700 g of mixed resin (9% HCO3- form and 91% Cl- form). The results indicate that all side effects of bicarbonate i.v. therapy of DKA coma are avoided because of the smooth HCO3- administration to the patient. Furthermore, a good removal of ketoanions and organic acids is obtained without changing the blood osmolality.

Advantages of one step nucleic acid amplification (OSNA) whole node assay in sentinel lymph node (SLN) analysis in breast cancer

BACKGROUND

The purpose of this study is to present our first results of sentinel node analysis (SLN) by one step nucleic acid amplification (OSNA) in routine clinical practice in our centre and compare them with the results of classic histopathological analysis in a historical cohort from our same institution.

METHODS

407 patients (total study population) with early breast cancer and no clinical nodal involvement underwent SLN biopsy in our institution. The SLN was analysed by OSNA in 164 biopsies. OSNA results were compared with the conventional histopathology study of 244 patients who had undergone SLN biopsy previously. The characteristics of the patients in both groups were evaluated and a comparison was made of the rate of metastases detected by both methods and of the surgical procedures needed in each group. We also investigated the state of non-sentinel lymph nodes if micrometastases where found in SLN.

RESULTS

SLN biopsy result was considered as positive in 45 patients (28%) in the OSNA group and in 58 in the historical group (24%). There was no difference in the rate of macrometastases (16,5% for OSNA, 20% for HE) but we found differences in the rate of micrometastases (11% for OSNA and 3,6% for HE p = 0.0007). Axillary lymphadenectomy (ALND) was performed in 43/45 cases in the OSNA group and in 51/58 of the historical group. In all patients diagnosed by OSNA, ALND was performed during the initial surgical procedure. In the historical cohort ALND was performed during the initial surgical procedure in 41 patients and in a second surgical procedure in 10 patients. Patients from both groups with micrometastases in the SLN had no metastases in other nodes when the ALND was performed.

CONCLUSIONS

OSNA analysis allows the detection of SLN metastases as precisely as conventional pathology with an increased detection of micrometastases. The OSNA method can reduce the need of a deferred lymphadenectomy.

405. Isolation and preliminary characterisation of putative sheep embryonic stem cells

The establishment of true, fully characterised embryonic stem (ES) cells from livestock, (eg sheep) has yet to be reported. Such cells could make a significant impact on assisted reproductive technologies, vaccine delivery, and animal health and well being in the livestock industries. To date in sheep, there is a single report of putative ES cells which were maintained in an undifferentiated state for only 2 passages. Here we report the isolation and culture of pluripotent ES-like cells from in vivo derived, vitrified, sheep blastocysts. The inner cell mass of blastocysts were isolated by immunosurgery, cultured in Stem Cell Sciences' (SCS) novel inhibitor-based media, on a feeder layer of mouse embryonic fibroblasts (MEFs), resulting in putative ovine ES cells proliferating to at least passage 5. One cell line, BMCOV002, was established out of four thaw-recovered embryos. The colonies formed compact, near homogenous, small cell, multilayered, and well defined dome shaped masses that were morphologically similar to both mouse and human ES cell colonies. A peripheral halo of filamentous differentiated cells was detected in selected colonies from passage 3 to passage 5. The putative ovine ES-like cells were passaged by mechanical excision between days 6–7, and these colonies stained positive for alkaline phosphatase at both passage 3 and passage 5. Expression levels of genes encoding the pluripotent transcription factors OCT4, SOX2, REX1 and NANOG are shown using RT PCR in cells from passage 3. An important first step in studying the properties of ovine ES-like cells is the ability shown here to isolate and culture cells. Our attention now is focussed on maintaining these cells for some months in an undifferentiated state, and on being able to successfully cryopreserve and regenerate these cell lines.

Integrated pollution prevention and control for heavy ceramic industry in Galicia (NW Spain)

The heavy ceramic industry (building materials and refractory products manufacture) is an important source of pollutants to the environment. For this reason these industrial sub-sectors are included in prevention and control pollution policies, specifically those of the European Union. The IPPC Directive pays particular attention to the mineral industries, not least to the ceramic industry (epigraph 3.5, Annex I). In this paper, a methodology which is being applied to support IPPC installations and the competent administrative authority in Galicia (NW Spain) is presented. For that, the Galician heavy ceramic industry is analysed, as also are the ways to study the Best Available Techniques (BAT) with a view to establishing the emission limit values (ELV) for each specific case. Hence, a technological state of the art has been carried out for both sub-sectors, from the point of view of implementation of the IPPC in Galicia. Following this, the processes are described briefly and an analysis of the consumption and emission levels of the main pollutants is made. An inventory that includes the best environmental practices and the preventive and abatement candidate techniques as BAT was elaborated for both considered sub-sectors. An information data sheet for each candidate BAT is presented as a method to help both the industries and the competent authority to identify a candidate technique of the inventory as BAT. Three illustrative examples of the application of this procedure are presented for different emissions to environmental media for Galician installations.

Ventricular natriuretic peptide (BNP) in heart transplantation: BNP correlation with endomyocardial biopsy, laboratory and hemodynamic measures

A prospective study of 81 heart transplant (HT) patients was carried out in order to evaluate the evolution of brain natriuretic peptide (BNP) levels in HT patients and compare them with the degree of rejection as determined by endomyocardial biopsy. All patients were subjected to endomyocardial biopsy (532), and determination of BNP and creatinine levels as well as hemodynamic parameters. A control group of 36 volunteers was included. BNP values were significantly greater in HT patients than in healthy volunteers. In the first 3 months, BNP levels in patients with treatable rejection were significantly greater than in patients without graft rejection, although evident overlapping was observed in both distributions and discriminatory potential was low. After the third month, BNP values were similar in patients with and without rejection. Creatinine levels were observed to increase over time after transplantation, but no correlation was observed between the creatinine and BNP levels. A significant positive correlation was observed between BNP and right ventricle and pulmonary arterial pressures.

[Bone scintigraphy and somatostatin receptor scintigraphy in pediatric patients with bone involvement in Langerhans cell histiocytosis]

Langerhans cell histiocytosis (LCH) is a granulomatous disease which can involve multiples sites of the body. Diagnostic imaging is of utmost importance in the management of these patients. Up to now radiographic skeletal survey and bone scintigraphy (BS) have been used to assess bone involvement (both with low specificity). Magnetic resonance imaging (MRI) and CT have been used to assess visceral involvement but with the limitation that they cannot give information about the functional status. Recently somatostatin receptor scintigraphy (SSRS) has been proposed to detect active lesions and to monitor response to treatment. The aim of this study is to assess bone and somatostatin receptor scintigraphy in the detection of bone involvement in LCH in children. Twenty scintigraphies (12 SSRS and 8 BS) were performed in seven patients (3 girls and 4 boys) aged at diagnosis: 18 month-12 years (mean age 6 years). The findings obtained in the scintigraphies were compared with clinical evolution and other imaging techniques. Bone scintigraphy detected all the LCH bone lesions, and discovered one unknown lesion. SSRS scintigraphy visualised the active lesions in 3 patients (clinical and other imaging techniques were also positive). SSRS was negative in one patient classified as disease free and another in clinical remission. SSRS detected 2 new unknown bone lesions, but could not detect LCH bone lesions confirmed in other imaging techniques in 2 patients. Somatostatin receptor and Bone scintigraphy can be used to detect active LCH bone lesions in children and can help to monitor response to treatment. Further studies with more patients are needed to confirm the diagnostic usefulness of these techniques.

Radioimmunometric assay of B-type natriuretic peptide (BNP) in heart transplantation: correlation between BNP determinations and biopsy grading of rejection

The aim of this study was to determine whether elevated brain natriuretic peptide (BNP) levels after heart transplantation are correlated with the severity of rejection by using endomyocardial biopsy (EMB) and echocardiographic parameters indicative of ventricular function of the transplanted heart. This was an observational study of 80 orthotopic heart transplant recipients (11 women and 69 men; mean age 53+/-11 years). BNP determinations were performed within 48 h of endomyocardial biopsy. The echocardiographic study and BNP determination were also performed in a group of healthy volunteers. We found significantly higher BNP mean levels in heart transplant patients than in healthy volunteers (volunteers, 16.7+/-16.2 pg.ml-1; transplant, 213.4+/-268.6 pg.ml-1; P<0.001). Transplant recipients with rejection grades 2, 3 and 4 on EMB had significantly higher BNP levels than those with rejection grades 0 and 1 (higher rejection grade, 162.5+/-168.4 pg.ml-1; lower rejection grade, 292+/-361.8 pg.ml-1; P<0.01). BNP values of patients with good left ventricular function (LVF) were significantly lower than in patients with mildly and moderately impaired LVF and patients with severely impaired LVF (good function, 199.76+/-233.6 pg.ml-1; mildly/moderately impaired LVF, 937+/-644.5 pg.ml-1; severely impaired LVF, 1038+/-491.2 pg.ml-1; P<0.001). It is concluded that BNP plasma levels are elevated in heart transplant patients compared to the normal population. The distribution of BNP levels in heart transplanted patients show a wide range. BNP elevation is greater in patients with higher rejection grades on EMB and greater impairment of left ventricular function.

Hodgkin's disease. Prognostic value of Gallium-67 scintigraphy

AIM

The aim of this study is to assess the clinical impact of gallium-67 scintigraphy, before and after treatment, in patients with Hodgkin's disease, and to compare the overall survival between the patients whose gallium studies after treatment were negative and those whose studies remained positive.

METHODS

We have studied 75 patients (40 women, 35 men) with Hodgkin's disease. All the patients underwent (67)Ga scintigraphy at the moment of the diagnosis (basal study) and in the case that basal study was positive (abnormal hyper-uptake focus) we performed follow-up studies after the treatment. We have calculated the overall survival among patients whose studies after treatment were negative (1(st) group) and those whose studies remained positive (2(nd) group) and between patients whose studies were negative at diagnosis (3(rd) group).

RESULTS

Gallium scintigraphy was positive at diagnosis in 47 patients (62.6%). In 39 of them we were able to perform the follow-up study after treatment. The follow-up study was negative in 31 patients while in 8 patients the gallium scintigraphy remained positive. The overall survival was significantly higher (p<0.001) in the 1(st) group compared with the 2(nd) group. The overall survival was higher in the 1(st) group compared with the 3(rd) but statistic significance level was not reached.

CONCLUSION

Our data suggest that: 1) in Hodgkin's disease (67)Ga scintigraphy is useful to establish the diagnosis of complete remission; 2) if the gallium scan remains positive after treatment, the prognosis of patients is worse than the prognosis of patients with a negative scan.

[Intestinal duplications. A survey of 18 cases]

OBJECTIVE

The present study analyses the experience of two centers in the management of intestinal duplications in children.

MATERIAL AND METHODS

We retrospectively reviewed the medical records of a series of 18 children with intestinal duplication (January 1993 to December 1999). The median age was 11 months (range: 9 days to 12 years). The variables analysed were: clinical presentation, diagnosis, localization, anatomic type, treatment, and complications. The relationship between age and clinical presentation was also analysed.

RESULTS

Most cases were located in the ileum (n 14; 78 %) and presented with rectal bleeding (36 %) or intussusception (36 %). Most symptomatic cases in the first year of life presented with intussusception (n 5/6). All duplications, except one located in the ascending colon, were cystic. 99mTc-pertechnate abdominal scan was positive in three out of five patients. One case was diagnosed by prenatal ultrasonography. Diagnosis was confirmed by laparoscopy in three patients and by laparotomy in the remaining patients. In one patient, cystic esophageal duplication presented in the neonatal period as respiratory distress. Diagnosis as well as excision was performed by thoracoscopy. Of the two gastric duplications, one was diagnosed by prenatal ultrasonography and the other by laparotomy. Treatment consisted of segmental enterectomy (n 14) or excision of the lesion without enterectomy (n 4). No complications were found during a mean follow-up of 3 years.

CONCLUSIONS

The onset of intestinal duplication may be late. The lesions were most commonly located in the ileum and were cystic. Clinical presentation was related to age. Minimally invasive surgery plays an important role in the management of these lesions.

Radioimmunometric assay of natriuretic peptide type-B (BNP) in heart failure

The aim of this study was to assess the value of the radioimmunometric determination of natriuretic peptide type-B (brain natriuretic peptide, BNP) in the diagnosis and prognosis of heart failure, and to study the association between BNP and the clinical, analytical and echocardiographic variables associated with the evolution of heart failure. The study group included 169 patients (74 women and 95 men; mean, 66 years) with heart failure of different causes, admitted consecutively to our hospital. BNP levels were measured with a radioimmunometric assay (Shionora BNP Cis ) after day 3 of admission. Patients were also studied by echocardiography. A significant association between the cause of heart failure and the BNP concentration was found (patients with ischaemic disease had the highest BNP values). Systolic function was worse in patients with ischaemic disease or dilated cardiomyopathy. High BNP values were also associated with advanced functional class and male sex. Plasma creatinine correlated positively with plasma BNP. However, we found no significant association with the other clinical variables evaluated. Of the echocardiographic variables analysed, BNP correlated positively with the ventricular diameter and pulmonary artery systolic pressure, and inversely with the shortening fraction; patients with severely impaired systolic function had the highest BNP values. It can be concluded that BNP levels (by radioimmunometric assay) are increased in patients with heart failure, and increase in relation to left ventricular dysfunction and the severity of heart failure. The strong independent association of plasma BNP with the left ventricular ejection fraction, its stability and the low cost of measurement suggest that plasma BNP assay could become a routine test. BNP assay could be included as an important factor in clinical and therapeutic decision making, as it complements the information provided by other variables used in the diagnosis of heart failure.

A protein-protein interaction map of the Caenorhabditis elegans 26S proteasome

The ubiquitin-proteasome proteolytic pathway is pivotal in most biological processes. Despite a great level of information available for the eukaryotic 26S proteasome-the protease responsible for the degradation of ubiquitylated proteins-several structural and functional questions remain unanswered. To gain more insight into the assembly and function of the metazoan 26S proteasome, a two-hybrid-based protein interaction map was generated using 30 Caenorhabditis elegans proteasome subunits. The results recapitulate interactions reported for other organisms and reveal new potential interactions both within the 19S regulatory complex and between the 19S and 20S subcomplexes. Moreover, novel potential proteasome interactors were identified, including an E3 ubiquitin ligase, transcription factors, chaperone proteins and other proteins not yet functionally annotated. By providing a wealth of novel biological hypotheses, this interaction map constitutes a framework for further analysis of the ubiquitin-proteasome pathway in a multicellular organism amenable to both classical genetics and functional genomics.

Is the depth correction using the geometric mean really necessary in a 99Tcm-DMSA scan in the paediatric population?

Determination of the left to right dimercaptosuccinic acid (DMSA) uptake ratio is theoretically one of the easiest quantitative procedures in nuclear medicine. The quantification can be performed on the posterior view, with or without the lateral view for correction of kidney depth. The geometric mean can also be determined using both the anterior and the posterior views. The aim of this study was to evaluate the occurrence of remarkable differences in the results from quantification of the relative renal function using the geometric mean and those obtained using the posterior counts only. Moreover, we evaluated to what extent the patient age influenced these differences. We reviewed 328 99Tcm-DMSA scans. The difference between the relative renal function obtained using the posterior view and that obtained using the geometric mean was calculated and analysed statistically. For the purpose of evaluating the value of performing the geometric mean calculation in patients of different ages, patients were divided into four age groups (group I, < or =2 years; group II, 3-9 years; group III, 10-18 years; group IV, >18 years). Using the Student's t test, no statistical differences were found in the relative renal function obtained by the two methods (posterior projection and geometric mean) in groups I (t = 0.01, P = 0.992) and II (t = 1.43, P = 0.155), which consisted of patients younger than 10 years (77% of the patients). In groups III and IV statistical differences were found (t = 2.27, P = 0.028 and t = 2.170, P = 0.038), respectively. We conclude that for children under 10 years it is unnecessary to perform depth correction using the geometric mean except in rare cases of major malformations and position anomalies.

Microvascularized fibular graft for mandibular reconstruction: detection of viability by bone scintigraphy and SPECT

Bone allografts are often used in reconstructive mandibular surgery, generally after extensive oncologic resection, post-traumatic pseudoarthrosis, or osteomyelitis. Vascularized fibular bone grafts have advantages compared with other bone grafts in the restoration of the contour and function of defective mandibles. Bone scintigraphy is often used to assess bone revascularization, because positive uptake of Tc-99m hydroxy methylene diphosphonate (HDP) reflects patent anastomoses and viability of the grafted bone. Mandibular reconstruction with a free fibular flap was performed in 11 patients. Bone scintigraphy and SPECT were applied in the follow-up of eight patients. The grafts were assessed semi-quantitatively using a six-grade scoring system based on a comparison of tracer uptake in the graft and in the calvarium. Complications were observed in one graft. Planar scintigrams showed a tracer uptake greater than grade 5 in grafts with an uncomplicated course. SPECT was performed in addition to planar imaging in two patients who had greater graft uptake. A lack of tracer uptake was observed in the failed graft. Bone scintigraphy performed within the first week after the mandibular reconstruction is a useful tool to monitor the viability and early complications of microvascularized fibular grafts and plays an important role in the decision-making process during repeated surgical exploration. SPECT is more sensitive than planar imaging for assessing graft viability.

Slap negatively regulates Src mitogenic function but does not revert Src-induced cell morphology changes

Src-like adapter protein (Slap) is a recently identified protein that negatively regulates mitogenesis in murine fibroblasts (S. Roche, G. Alonso, A. Kazlausakas, V. M. Dixit, S. A. Courtneidge, and A. Pandey, Curr. Biol. 8:975-978, 1998) and comprises an SH3 and SH2 domain with striking identity to the corresponding Src domains. In light of this, we sought to investigate whether Slap could be an antagonist of all Src functions. Like Src, Slap was found to be myristylated in vivo and largely colocalized with Src when coexpressed in Cos7 cells. Microinjection of a Slap-expressing construct into quiescent NIH 3T3 cells inhibited platelet-derived growth factor (PDGF)-induced DNA synthesis, and the inhibition was rescued by the transcription factor c-Myc but not by c-Jun/c-Fos expression. Fyn (or Src) overexpression overrides the G(1)/S block induced by both SrcK- and a Slap mutant with a deletion of its C terminus (SlapDeltaC), but not the block induced by Slap or SlapDeltaSH3, implying that the C terminus is a noncompetitive inhibitor of Src mitogenic function. Furthermore, a chimeric adapter comprising SrcDeltaK fused to the Slap C terminus (Src/SlapC) also inhibited Src function during the PDGF response in a noncompetitive manner, as Src coexpression could not rescue PDGF signaling. Slap, however, did not reverse deregulated Src-induced cell transformation, as it was unable to inhibit depolymerization of actin stress fibers while still being able to inhibit SrcY527F-induced DNA synthesis. This was attributed to a distinct Slap SH3 binding specificity, since the chimeric Slap/SrcSH3 molecule, in which the Slap SH3 was replaced by the Src SH3 sequence, substantially restored stress fiber formation. Indeed, three amino acids important for ligand binding in Src SH3 were replaced in the Slap SH3 sequence; Slap SH3 did not bind to the Src SH3 partners p85alpha, Shc, and Sam68 in vitro, and the chimeric tyrosine kinase Slap/SrcK, composed of SlapDeltaC fused to the SH2 linker kinase sequence of Src, was not regulated in vivo. Furthermore, the Src SH3 domain is required for signaling during mitogenesis and since Slap/SrcK behaved as a dominant negative in the PDGF mitogenic response when microinjected into quiescent fibroblasts. We conclude that Slap is a negative regulator of Src during mitogenesis involving both the SH2 and the C terminus domains in a noncompetitive manner, but it does not regulate all Src function due to specific SH3 binding substrates.

[Myocardial damage following neonatal severe asphyxia]

Sixteen newborn infants with severe asphyxia were prospectively studied for evidence of secondary myocardial damage and, in that case, their clinical findings. Myocardial damage was diagnosed in three term newborn infants of adequate weight for gestational age (18.7%) by means of serial electrocardiograms taken in the first 72 hours of life. Two of them showed evidence of diffuse subendocardial ischemia and a third one showed electrocardiographic signs suggesting necrosis of the left ventricular posteroinferior wall. Neither creatine-phosphokinase serum activity nor its muscle brain MB isoenzyme were useful in the identification of myocardial damage. All three affected neonates developed respiratory distress syndrome without signs of cardiac failure and one of them died. The histopathological study of this late one showed localized hemorrhage of the papillary muscles and interventricular septum. These finding underscore the need for serial electrocardiographic recordings in newborns with severe asphyxia, since cardiac dysfunction may inadvertently occur under the appearance of respiratory distress syndrome.

Further studies on the realization of a cold carbon portable artificial kidney

Optimal conditions have been determined for the realization of a closed-loop, cold carbon, portable artificial kidney to depurate the dialysate of urea and other catabolites. It has been noticed that a dialysate flow rate of about 250 ml/min represents an optimal compromise between urea mass transfer through the dialytic membrane and its mass adsorption on cold carbon. Under this condition, the use of a 2-kg carbon column to remove urea is satisfactory for a routine dialysis treatment. Our experiments have been performed on simulated dialysis. A portable cold carbon artificial kidney requires a cooling unit and a heat exchanger to recover the power necessary to produce the 0 degrees C temperature. A flat heat exchanger, consisting of three superposed plates, with a heat exchange surface of about 0.09 m2 and a total coefficient of thermal exchange Ht, of 380 Kcal/m2-degrees C-hour has been chosen. With heat recovery, the cooling power required is 1/3 hp to allow for parasitic cold losses and the power necessary to reach a steady state. All mechanical parts necessary for heating and cooling weigh about 12 kg.

[Bacteriocins as cytotoxic agents in experimental neoplasms: considerations on the role of possible contaminants]

In most recent papers some Authors have demonstrated that several bacteriocins are able to markedly inhibit the division of various neoplastic mammalian cell lines; also in vivo the inhibition of tumor growth or even regression relative to controls are statistically significant. Since such preparations are "crude" and it's possible that contaminating agents may represent a possible source of variability in the results, mostly in vivo; we have examined a preparation of Pyocin employed in this study for the possible endotoxin contamination using the Limulus assay. Such test was positive in triplicate and semiquantitative determination has shown and endotoxin amount of 5 to 10 microgram/ml. This level is, in vitro, not anough to give cytotoxic effect, but in vivo is able to influence experimental results. In addition, since some bacteriocins and enterotoxins are produced under exactly identical conditions, there is this a possibility that the enterotoxin are coproduced in these preparations and are causing some of the cytotoxic effects on experimental tumors. A more complete separation and purification of preparations will be required before definitive comments.

Cold carbon apparatus for hemodialysis

A prototype of artificial kidney with regeneration of the dialysis fluid in active carbon at low temperature is presented. The data obtained through a series of simulated dialysis show that carbon adsorbs, besides creatinine and other compounds, urea in satisfactory quantities. Furthermore, the possibility of completely regenerating carbon with tap water washing makes the routine use of an artificial kidney based on a cold operating carbon depurator extremely practical.