Rapid systematic review of interventions to improve antenatal screening rates for syphilis, hepatitis B, and HIV in low- and middle-income countries

BACKGROUND

Infectious diseases including syphilis, HIV, and hepatitis B are major contributors to maternal and neonatal morbidity and mortality worldwide, especially in low- and middle-income countries (LMICs). The World Health Organization has prioritized elimination of vertical transmission of these three diseases.

OBJECTIVES

To rapidly assess the impact of interventions designed to improve antenatal screening rates for syphilis, HIV, and hepatitis B in LMICs and to identify areas for future implementation research.

SEARCH STRATEGY

A comprehensive search was conducted across PubMed, Embase, and EconLit, targeting articles published between January 1, 2013, and June 27, 2023.

SELECTION CRITERIA

We included quantitative interventional studies in English, involving pregnant adults (15 years or older) from LMICs. Exclusions were studies based in high-income countries, qualitative studies, or those investigating accuracy of diagnostic methods.

DATA COLLECTION AND ANALYSIS

From an initial 5549 potential studies, 27 were finalized for review after various screening stages. Data extraction covered aspects such as study design, intervention details, and outcomes. Findings were qualitatively synthesized within a systems thinking framework.

MAIN RESULTS

The interventions assessed varied in terms of geographic locations, health care system levels, and modalities. The review highlighted the effectiveness of interventions such as community health interventions, service quality improvements, and financial incentives.

CONCLUSIONS

The study underscores the potential of specific interventions in enhancing antenatal screening rates in LMICs. However, there is a discernible research gap concerning hepatitis B. The findings emphasize the importance of capacity building and health systems strengthening in public health interventions.

Effect of preoperative chemotherapy on the histopathological classification of gastric cancer

BACKGROUND

In the era of individualized gastric cancer (GC) treatment, accurate determination of histological subtype becomes increasingly relevant. As yet, it is unclear whether preoperative chemotherapy may affect the histological subtype. The aim of this study was to assess concordance in histological subtype between pretreatment biopsies and surgical resection specimens before and after the introduction of perioperative treatment.

METHODS

Histological subtype was centrally determined in paired GC biopsies and surgical resection specimens of patients treated with either surgery alone (SA) in the Dutch D1/D2 study or with preoperative chemotherapy (CT) in the CRITICS trial. The histological subtype as determined in the resection specimen was considered the gold standard. Concordance rates and sensitivity and specificity of intestinal, diffuse, mixed, and "other" subtypes of GC were analyzed.

RESULTS

In total, 105 and 515 pairs of GC biopsies and resection specimens of patients treated in the SA and CT cohorts, respectively, were included. Overall concordance in the histological subtype was 72% in the SA and 74% in the CT cohort and substantially higher in the diffuse subtype (83% and 86%) compared to the intestinal (70% and 74%), mixed (21% and 33%) and "other" subtypes (54% and 54%). In the SA cohort, sensitivities and specificities were 0.88 and 0.71 in the intestinal, 0.67 and 0.93 in the diffuse, 0.20 and 0.98 in the mixed, and 0.50 and 0.93 in the "other" subtypes, respectively.

CONCLUSION

Our results suggest that accurate determination of histological subtype on gastric cancer biopsies is suboptimal but that the impact of preoperative chemotherapy on histological subtype is negligible.

Adjuvant chemotherapy is superior to chemoradiation after D2 surgery for gastric cancer in the per-protocol analysis of the randomized CRITICS trial

BACKGROUND

The Intergroup 0116 and the MAGIC trials changed clinical practice for resectable gastric cancer in the Western world. In these trials, overall survival improved with post-operative chemoradiotherapy (CRT) and perioperative chemotherapy (CT). Intention-to-treat analysis in the CRITICS trial of post-operative CT or post-operative CRT did not show a survival difference. The current study reports on the per-protocol (PP) analysis of the CRITICS trial.

PATIENTS AND METHODS

The CRITICS trial was a randomized, controlled trial in which 788 patients with stage Ib-Iva resectable gastric or esophagogastric adenocarcinoma were included. Before start of preoperative CT, patients from the Netherlands, Sweden and Denmark were randomly assigned to receive post-operative CT or CRT. For the current analysis, only patients who started their allocated post-operative treatment were included. Since it is uncertain that the two treatment arms are balanced in such PP analysis, adjusted proportional hazards regression analysis and inverse probability weighted analysis were used to minimize the risk of selection bias and to estimate and compare overall and event-free survival.

RESULTS

Of the 788 patients, 478 started post-operative treatment according to protocol, 233 (59%) patients in the CT group and 245 (62%) patients in the CRT group. Patient and tumor characteristics between the groups before start of the post-operative treatment were not different. After a median follow-up of 6.7 years since the start of post-operative treatment, the 5-year overall survival was 57.9% (95% confidence interval: 51.4% to 64.3%) in the CT group versus 45.5% (95% confidence interval: 39.2% to 51.8%) in the CRT group (adjusted hazard ratio CRT versus CT: 1.62 (1.24-2.12), P = 0.0004). Inverse probability weighted analysis resulted in similar hazard ratios.

CONCLUSION

After adjustment for all known confounding factors, the PP analysis of patients who started the allocated post-operative treatment in the CRITICS trial showed that the CT group had a significantly better 5-year overall survival than the CRT group (NCT00407186).

Plattenepithelkarzinom der Schilddrüse ausgehend von einer Ductus thyreoglossus Zyste

Es wird über eine 73jährige Patientin mit dem sehr seltenen Fall eines Karzinoms berichtet, das sich in einer Ductus thyreoglossus-Zyste innerhalb einer Struma diffusa et nodosa entwickelt hatte. Zusätzlich bestand eine Immunthyreopathie Typ Basedow. Sonographische, röntgenologische, szintigraphische und histologische Befunde werden vorgestellt.

3,5,3’-Triiodothyroacetic Acid (TRIAC) Effects on Pituitary Thyroid Regulation and on Peripheral Tissue Parameters

The effects of TRIAC on peripheral thyroid hormones, TSH incretion and peripheral tissue parameters were investigated in 13 mildly obese patients (group I) and 10 volunteers of normal body weight (group II). TRIAC was administered 3x1 mg daily over a period of 8 days to both groups. In group I (on a 400 kcal low caloric diet) bTSH and fT4 decreased significantly whereas TT4 decreased only insignificantly. TT3 and fT3 rose significantly due to the cross-reactivity of the employed antibody. The peripheral tissue parameters cholesterol, ankle jerk and systolic time interval did not reveal any changes suggesting an increase in metabolic rate. The increase in heart frequency was not significant either. The significant rise in sex-hormone binding globulin was most probably associated with the weight reduction of 3.1 ± 1.2 kg per week. In group II (on normal diet) bTSH and fT4 decreased significantly whereas TT4 decreased only insignificantly. As in group I, TT3 and fT3 rose significantly. Also in group II TRIAC did not cause alterations in the peripheral tissue parameters. In contrast to the obese group the volunteers in group II showed no significant rise in sex-hormone binding globulin and no reduction of body weight. Side effects such as nervousness, tremor or palpitations were not observed. Thus, TRIAC does not induce an increase in peripheral metabolic rate, not even under a TSH-suppressive dose as high as 3 x 1 mg per day.

Schilddrüsenvolumina und Jodversorgung 6- bis 17jähriger Schüler

In Österreich wurde 1963 eine gesetzlich vorgeschriebene Speisesalzjodierung mit 10 mg KJ/kg eingeführt. Dennoch zeigten Untersuchungen zur Jodversorgung zwischen 1982 und 84 nach wie vor einen Jodmangel Grad I bis II. Dies führte 1990 zur Anhebung der Speisesalzjodierung auf 20 mg KJ/kg Vollsalz. Ziel der Untersuchung war es, die Jodversorgung und die Schilddrüsenvolumina von Schülern 3 Jahre nach Einführung der erhöhten Jodsalzprophlyaxe zu überprüfen. Durchgeführt wurde eine stichprobenartige Untersuchung an 734 Schülern der 1. bis 12. Schulstufe. Der Mittelwert der Harnjodidausscheidung betrug 121 ug/g Kr; dies bedeutet gebenüber den Voruntersuchungen von 1984 einen deutlichen Anstieg der Jodversorgung. Gegenüber den Vergleichsdaten zeigten die entsprechenden Altersgruppen geringere mittlere Schilddrüsenvolumina.

201TI Myocardial SPECT and ß-Endorphin Levels in Patients with Suspected Silent Ischemia

Today silent myocardial ischemia (SMI) is a well-recognized phenomenon. However, in the absence of clinical signs suggesting coronary artery disease (CAD), a streamlined diagnostic approach for precise clarification has proved to be difficult. Sensitivity and specificity of ergometric results are rather poor in symptom-free patients. Thus the question arises, whether the necessity of coronary angiography can be established more precisely by 201TI myocardial SPECT in these patients. Treadmill exercise according to the Bruce protocol, 201TI myocardial SPECT and coronary angiography were performed in a total of 106 patients with suspected SMI. In group I (high probability of ischemia; n = 46), reversible defects detected by SPECT correlated well with significant stenoses and irreversible defects with subtotal stenoses or complete occlusions. SPECT sensitivity in the detection of ischemia was 91 %, its specificity 96%. In group II (low probability of ischemia; n = 60), SPECT sensitivity was as high as in group I (94%) but due to a high number of false-positive results (e. g. cardiomyopathy) specificity was only 75%. However, SPECT was superior to exercise ECG (sensitivity 70%; specificity 56%) in the detection of SMI. In addition, ß-endorphin levels were determined in 180 healthy subjects, 37 patients with symptomatic CAD and in 34 patients with SMI before and during maximum exercise. Exercise values in patients with SMI were significantly higher than in healthy subjects or in patients with symptomatic CAD.

Preoperative Scintigraphic and Intraoperative Scintimetric Localization of Parathyroid Adenoma with Cationic Tc-99m Complexes and a Hand-Held Gamma-Probe

Aim: The aim of our study was to evaluate the possibility of intraoperative scintimetric detection of parathyroid adenomas with Tc-99m labelled tracers for its usefulness in dystopic or ectopic adenomas. Methods: 12 women with biochemically confirmed hyperparathyroidism were included in our study. After injection of 370 MBq Tc-99m tetrofosmin e.g. sestamibi, preoperative scintigraphy (double phase study and SPECT) was performed and T/NT ratios were evaluated for early, delayed and SPECT images. Surgery was performed using a handheld gamma-probe after preoperative injection of 555-925 MBq Tc-99m tetrofosmin e.g. sestamibi. Count rates (cts/10 sec) were measured and used for calculating in situ - and ex situ - T/NT ratios. Results: In 9 out of 12 patients, adenoma could be detected on static images. Mean T/NT ratios for Tc-99m tetrofosmin were 1.29 for early and 1.23 for delayed images, respectively 1.39 and 1.23 for early and delayed Tc-99m sestamibi scan. Three cases could only be detected with SPECT reconstruction. 11 of 12 parathyroid adenomas could be confirmed intra-operatively. Conclusion: SPECT with Tc-99m labelled cationic complexes showed advantages in detection, precise localization and contrast over static scintigraphy and should therefore be performed at least in cases with poor or no uptake on static images to avoid failures in detection of deeply sited, dislocated glands or adenomas with low uptake. Intraoperative localization and confirmation of parathyroid adenoma with Tc-99m-labelled cationic complexes and a gamma probe is possible and may be useful in case of dys- or ectopic adenoma by influencing surgical approach and operating time.

99mTc-markierte Anti-CEA-Antikörper in der intraoperativen Diagnostik kolorektaler Karzinome

Eine stadiengerechte Therapie kolorektaler Malignóme setzt die exakte Kenntnis des Tumorstadiums voraus. Intraoperativ ist dies für die Beurteilung der Operationsradikalität und die Planung weiterführender adjuvanter oder palliativer Behandlungsmodalitäten unerläßlich. In einer kontrollierten prospektiven Studie, an der 20 Patienten teilnahmen, wurde versucht, den Stellenwert nuklearmedizinischer Untersuchungen unter diesem Aspekt zu evaluieren. Mit 99mTc markierte Antikörper gegen zelluläre CEA-Epitope wurden zur intraoperativen Szintimetrie eingesetzt. Die Meßergebnisse wurden mit jenen der etablierten Verfahren verglichen und histopathologisch überprüft. Die intraoperative Szintimetrie erlaubt die exakte Lokalisation metastatischer Absiedelungen. Die Radikalität der Operation kann zuverlässig festgestellt werden. Die Immunszintimetrie ermöglicht somit eine exakte Stadienzuordnung zu einem frühen und therapeutisch relevanten Zeitpunkt.

Diagnose einer Achalasie durch 99mTc-Pertechnetat-Szintigraphie

Eine 73jährige Patientin zeigte bei der 99mTc-Schilddrüsenszintigraphie eine von der Schilddrüse abgesetzte deutliche fokale Speicherung links kaudal der Schilddrüse. Die weitere diagnostische Abklärung mittels Sonographie, CT, Ösophagoskopie und videoassistiertem Kontrastmittelschluckakt ergab als Ursache der 99mTc-Speicherung eine Achalasie. Die Erklärung einer 99mTc-Speicherung in der Speiseröhre wäre die unspezifische 99mTc-Aufnahme in den Speicheldrüsen mit nachfolgender Tracerelimination über den Speichel. Depotbildungen von Speichel bei Erkrankungen der Speiseröhre, die mit einer Transportstörung des Speichels verbunden sind, können dadurch Schilddrüsengewebe vortäuschen.

Diagnostik der SDAT mittels HMPAO-SPECT und Serumvitamin-B12-Spiegel

Die alleinige klinische Abklärung dementieller Zustandsbilder, so auch der senilen Demenz vom Alzheimertyp (SDAT), ist schwierig. Durch die Kombination von 99mTc-HMPAO-Gehirn-SPECT und Serumvitamin-B12-Bestimmung erwarteten wir eine Beschleunigung und Verbesserung der Diagnostik der SDAT. Von 116 Patienten, die in 4 Gruppen, entsprechend ihrem 99mTc-HMPAO-Verteilungsmuster eingeteilt worden waren, konnten bei 17 klinisch sehr wahrscheinlichen SDAT-Patienten bei 15 Auffälligkeiten mit Hinweis auf SDAT im Gehirn SPECT gefunden werden. Ein Teil der Patienten wies einen niedrig-normalen bzw. pathologisch niedrigen Vitamin-B12-Spiegel auf. Andere Untersuchungen würden durch die Kombination von Gehirn-SPECT und Serumvitamin-B12-Bestimmung nicht überflüssig werden, obwohl beide Untersuchungen Informationen lieferten, die die Zuordnung zur Diagnose SDAT erleichterten. Die zusätzliche Serumvitamin-B12-Bestimmung stellt keinen wesentlichen Mehraufwand dar.

Schilddrüsenhemiagenesie mit Immunthyreopathie

Die Hemiagenesie der Schilddrüse stellt eine seltene angeborene Veränderung dar. Diese angeborene Variante der Schilddrüsenanlage wird in den meisten Fällen durch Auffälligkeiten der Funktion oder der Größe des vorhandenen Schilddrüsenlappens zufällig gefunden. Der Fall einer 57jährigen Frau mit einer Schilddrüsenhemiagenesie in Kombination mit einer Immunthyreopathie Basedow wird vorgestellt. Die Zuweisung der Patientin zur Untersuchung erfolgte wegen einer Schilddrüsenüberfunktion. Die erforderlichen diagnostischen Schritte zur Erstellung dieser beiden Schilddrüsenveränderungen waren ein 99m-Tc-Schilddrüsenszintigramm, Ultraschall und Laborparameter der Schilddrüse (fT4, TT3, bTSH, TAK, TPO, TRAK).

Tc-99m-Tetrofosmin Scintigraphy: An Alternative Scintigraphic Method for Following up Differentiated Thyroid Carcinoma

Aim: The usefulness of the myocardial perfusion agent, Tc-99m-tetrofosmin (Myoview®) in the follow-up of differentiated thyroid carcinoma was evaluated in a clinical study of 15 patients, primary treated with thyroidectomy and high-dose I-131-therapy (2960-3700 MBq), 12 with suspected recurrence and metastases and three patients without any suspicion and compared with other non-specific tracers like TI-201 and Tc-99m-sestamibi. Method: Twelve patients with elevated thyroglobulin (Tg) levels of more than 10 ng/ml (group A), four of these had negative I-131 scans, and three patients with Tg levels less than 10 ng/ml (group B) were examined under TSH suppressive L-Thyroxine treatment. Whole body scans were taken with TI-201 (74 MBq; 20 min post injection), Tc-99m-sestamibi (370 MBq; 20-60 min post injection) and Tc-99m-tetrofosmin (370 MBq; 20-60 min post injection). Tumor/background ratios and optional time/activity analyses (up to 150 min post injection) were evaluated using the region of interest approach. Results: Compared with TI-201 (T/BG: 1.59, ± 0.396), Tc-99m-tetrofosmin showed slightly but not significant better T/BG ratios and detection rates (T/BG: 1.76, ± 0.345).Tc-99m-sestamibi (1.51, ± 0.31 p = 0.05) showea significantly lower values than Tc-99m-tetrofosmin. Conclusion: In the light of these results, scintigraphy with Tc-99m-tetrofosmin seems to be a possibly sensitive imaging modality in the follow-up of DTC with possible advantages concerning T/Bg ratio, background clearance, detection rate and dosimetry compared with TI-201 and Tc-99m-sestamibi, especially in patients with elevated Tg level and no iodine uptake , but further investigations are needed to confirm our preliminary results.

Tc-99m-Tetrofosmin Scintimammography: A Prospective Study in Primary Breast Lesions

Despite low specificity routine mammography is the method of choice to screen women for breast cancer. In addition high frequency ultrasonography (US) or magnetic resonance imaging (MRI) can improve breast cancer diagnosis. However there is a lack of conventional imaging to improve the high rate of false positive results that make biopsy or surgery necessary. Aim: The purpose of our study was to evaluate prospectively the sensitivity, specificity, PPV and NPV of scintimammography with a new cationic complex Tc-99m-tetrofosmin. Methods: Fourtyeight patients in whom mammography and/or high resolution ultrasonography (10MHz) revealed suspicious breast lesions were studied with Tc-99m-tetrofosmin scintimammography. In thirtyfour of them biopsy and/or surgery was performed for histological evaluation. After intravenous injection of 555 MBq Tc-99m-tetrofosmin dynamic images over three minutes (1 frame/10 sec.) planar images in anterior and lateral projections (5 min. p.i.) and SPECT imaging including 3-D-reconstruction (20 min. p.i.) were performed. Scintimammography was evaluated as negative, equivocal (+), probably (++) or definitely (+++) positive. Results: Scintimammography with Tc-99m-tetrofosmin was negative in 18 patients (17 t.n.; 1 f.n.) and positive in 16 patients (10 t.p., 6 f.p.). The false negative scintimammography was observed in a patient with infiltrating ductal carcinoma pT1, the false positive result in a patient with fibrocystic disease; all of the five fibroadenomas were also “false” positive. Sensitivity of Tc-99m-tetrofosmin scintimammography in this prospective study was 91 %, specificity 74%, PPV 63% and NPV 94%. Scintimammographic results in patients with suspicious breast lesion show, that Tc-99m-tetrofosmin accumulates in breast cancer as well as in fibroadenoma. However the high NPV of 94 % excludes breast cancer in suspicious mammographie lesions in a very high degree and therefore reduces the need of biopsy and/or surgery in most of these patients. Conclusion: Our first results show that scintimammography with Tc-99m-tetrofosmin might play a role as further diagnostic step before surgery for women in whom mammography and/or ultrasonography show suspicious lesions.

Tc-99m ciprofloxacin in clinically selected patients suspected for peripherial osteomyelitis, spondylodiscitis and fever of unknown origin: preliminary results

Aim: Retrospective evaluation of Tc-99m ciprofloxacin (infecton) scintigraphy consecutively performed in a series of patients clinically suspected for peripheral osteomyelitis (OM), spondylodiscitis (SD) and fever of unknown origin (FUO). Methods: A total of 20 patients clinically suspected for OM (n = 12), SD (n = 3) and FUO (n = 5) were included in our retrospective analysis. The additional criterion was a positive 3-phase bone scan for OM, or a 2-phase bone scan in case of SD. Planar whole body scans and static acquisitions were performed 1 and 4 h after application of 370 MBq Tc-99m ciprofloxacin. In 10 patients with suspected OM, additional immunoscintigraphy using Tc-99m labelled monoclonal antibodies (Mab BW 250/183) was performed and the correlation of infecton to bloodpool and antigranulocyte scintigraphy was analysed. Results: OM: Bacterial infection was confirmed in 8 of 15 lesions. Infecton demonstrated true positive (TP) results in 7 of 8, true negative (TN) results in 2 of 7, false positive (FP) results in 5 of 7 patients and one false negative (FN) result. A strong correlation could be demonstrated between T/NT ratios of infecton and bloodpool Tc-99m medronate imaging (r = 0.84, 0.88) and between infecton and BW 250/183 (r = 0.92, 0.90). Using a threshold of 2.0 for T/NT ratio, only TP results could be observed whereas a T/NT in the range of 1.0-2.0 could not discriminate between septic and aseptic inflammation. Concordant results with Mab BW 250/183 could only be observed in 5 of 10 patients (4 TP, 1 TN) by showing 4 FP and 1 FN lesions with IF. Conclusion: Non-specific uptake of infecton can be observed in a variety of clinical situations with moderate uptake, by showing a strong correlation with blood-pool imaging. Nevertheless, intense uptake may be specific for septic inflammation.

Results of preoperative ultrasound guided fine needle aspiration biopsy of solitary thyroid nodules as compared with the histology

Aim: The goal of this study was to assess the accuracy and limitations of ultrasound guided fine-needle aspiration biopsy (ug-FNAB) of solitary thyroid nodules. Methods: The ug-FNAB results of 538 patients with solitary thyroid nodules, who afterwards underwent thyroid surgery, were compared retrospectively with the histology. Patients with multinodular goiter were excluded from the study. Ug-FNAB was performed on growing and/or hypoechoic and/or hypofunctional nodules. The ug-FNAB results were grouped as follows: group 1: malignant (n = 44); group 2: malignancy cannot be ruled out (n = 173); group 3: non-malignant (n = 296), group 4: inadequate (n = 25). Results: When the cytological results of group 1 and group 2 were interpreted os being malignant and those of group 3 as being benign, sensitivity, specificity and accuracy of ug-FNAB were 96.7%, 65.8% and 69.5% respectively. The 62 thyroid carcinomas (TO biopsied presented in 59 cases a suspicious or malignant cytology (95.2%). The smallest TC diagnosed by ug-FNAB had a diameter of 0.5cm and 36.4% of all papillary TC ≤ 1 cm displayed stage pT4. The histology verified a TC in 18 cases out of the 173 ug-FNABs in group 2. Non-malignant ug-FNABs were confirmed by histology in 294 patients (99.3%) in group 3. In 4.65% of the ug-FNABs inadequate material was aspirated. Conclusion: Nodules with non-suspicious ug-FNAB results can be safely followed-up by sonography, as the cytological diagnoses were verified in more than 99% by histology. Papillary TC can be diagnosed with ug-FNAB very accurately. As stage pT4 was present in more than one third of patients with papillary TC ≤ T cm, ug-FNAB is also recommended for thyroid nodules 0.5-1 cm in diameter located adjacent to the thyroid capsule. However, microfollicular proliferations remain the limitation of ug-FNAB, as the cytology cannot distinguish between benign adenoma and follicular TC.

Is there a role for scintigraphic imaging of bone manifestations in Gaucher disease?

Gaucher disease is the most prevalent inherited, lysosomal storage disease and is caused by deficient activity of the enzyme β-glucocerebrosidase. Bone and bone marrow alterations are frequent in the most prevalent non-neuronopathic form of Gaucher disease. Imaging of bone manifestations in Gaucher disease is performed by a variety of imaging methods, conventional X-ray and MRI as the most frequently and most important ones. However, different modalities of scintigraphic imaging have also been used. This article gives an overview on scintigraphic imaging with respect to bone manifestations in Gaucher disease discussing the advantages and limitations of scintigraphic imaging in comparison to other imaging methods.

Promoting learning and innovation in organizations through complexity leadership theory

Purpose

Current organizations face a complex competitive landscape driven by globalization and technology that puts them in the course of a new economic age. This complexity stresses learning and innovation as fundamental mechanisms for organizational survival. This paper aims to propose that how learning and innovation emerge and affect organizational performance can be better understood through the complexity leadership theory.

Design/methodology/approach

The authors review literature on complexity leadership theory, learning and innovation in complex bureaucratic environments and then present reflections regarding how learning and innovation can be achieved through the interaction of three complexity leadership functions: adaptive, administrative and enabling. This conceptual framework suggests that individuals are in constant interaction, exchange information, influence each other and collectively produce emergent properties that promote effective learning and innovation.

Findings

We propose that learning and innovation can be better achieved in organizations if the complexity leadership theory is applied as an alternative to centralized forms of influence and control.

Originality/value

This paper presents a reflection on the benefits of the complexity leadership theory as an alternative framework to understand organizational leadership. Furthermore, this paper proposes that the complexity leadership theory is more adequate to generate learning and innovation in complex, fast-changing work environments.

Inhibition of SIV and HIV-2 Replication in Cynomolgus Monkeys by (-)9-[4-Hydroxy-2-(Hydroxymethyl)-Butyl]Guanine (H2G)

The antiherpes compound (-)9-[4-hydroxy-2-(hydroxymethyl)butyl]guanine (H2G) has been found to suppress the multiplication of SIVsm and HIV-2 in cynomolgus monkeys. This was seen as a delay in the appearance of viral antigen in serum during the primary infection at drug concentrations of 3×10 mg kg−1 day−1 and higher, when H2G was given subcutaneously. These effects of H2G on SIVsm and HIV-2 replication in monkeys were similar to those observed using the same dose of 3′-azidothymidine (AZT). A complete prevention of HIV-2 infection was observed in one of four animals treated with 3×10 mg kg−1 day−1 of H2G. The enantiomeric mixture (+)H2G at 3×25 mg kg−1 day−1 also delayed the appearance of SIVsm antigen but the (+)enantiomer of H2G at 3×10 mg kg−1 day−1 had no effect on primary SIVsm infection in monkeys, indicating that only the (−)enantiomer (H2G) was inhibitory and that this effect was not influenced by the presence of the (+)enantiomer. No adverse effects on blood chemistry or haematology were observed in monkeys given 25 mg kg−1 day−1 of H2G for 9 weeks or 3×25 mg kg−1 day−1 for 10 days.

A randomized clinical trial of neoadjuvant chemotherapy versus neoadjuvant chemoradiotherapy for cancer of the oesophagus or gastro-oesophageal junction

BACKGROUND

Neoadjuvant therapy improves long-term survival after oesophagectomy, treating oesophageal cancer, but the evidence to date is insufficient to determine which of the two main neoadjuvant therapy types, chemotherapy (nCT) or chemoradiotherapy (nCRT), is more beneficial. We aimed to compare the effects of nCT with those of nCRT.

PATIENTS AND METHODS

This multicentre trial, which was conducted in Sweden and Norway, recruited 181 patients with carcinoma of the oesophagus or the gastro-oesophageal junction who were candidates for curative-intended treatment. The primary end point was histological complete response after neoadjuvant treatment, which has been shown to be correlated with increased long-term survival. Study participants were randomized to nCT or nCRT, followed by surgery with two-field lymphadenectomy. Three cycles of platin/5-fluorouracil were administered in both arms, whereas 40 Gy of concomitant radiotherapy was added in the nCRT arm.

RESULTS

The trial met the primary end point, histological complete response being achieved in 28% after nCRT versus 9% after nCT (P = 0.002). Lymph-node metastases were observed in 62% in the nCT group versus 35% in the nCRT group (P = 0.001). The R0 resection rate was 87% after nCRT and 74% after nCT (P = 0.04). There was no difference in overall survival between the treatment arms.

CONCLUSION

The addition of radiotherapy to neoadjuvant chemotherapy results in higher histological complete response rate, higher R0 resection rate, and a lower frequency of lymph-node metastases, without significantly affecting survival.

CLINICALTRIALSGOV

NCT01362127 (https://clinicaltrials.gov; The full study protocol was registered in the Clinical Trials Database).

[Treatment of patients with radioiodine refractory, differentiated thyroid carcinoma. A Consensus Statement]

There is no clear standard therapy for patients with radioactive iodine (131I)-refractory locally advanced or metastatic differentiated thyroid cancer. The therapeutic options for this indication have expanded with the recently approved multiple kinase inhibitor sorafenib. Recommendations for the definition and the management of iodine refractory patients were worked up by an interdisciplinary expert panel, consisting of endocrine surgeons, medical oncologists and nuclear medicine specialists.

Abstract P5-18-18: Lapatinib versus trastuzumab, or both, added to preoperative chemotherapy for breast cancer: A meta-analysis of randomized evidence

Purpose: We compared the efficacy and safety of the addition of lapatinib versus trastuzumab, or the combination, to neoadjuvant chemotherapy in HER2-positive breast cancer.

Methods: Potentially eligible trials were identified through PubMed and Cochrane Library searches and abstracts of major international conferences. The endpoints that we assessed were pathologic complete response (pCR) rate and toxicity. Pooled relative risks (RR) were estimated for each endpoint with fixed or random effects models, depending on between-studies heterogeneity.

Results: Six trials were identified with 1494 eligible patients. The probability to achieve pCR was higher for the trastuzumab plus chemotherapy arm than lapatinib plus chemotherapy (RR 1.25, 95% Confidence Interval (CI): 1.08–1.43; p-value = 0.003) (6 trials; 1494 patients). Furthermore, the probability for pCR was significantly higher in the group given both lapatinib and trastuzumab than in the group given trastuzumab alone (RR 1.39, 95% CI: 1.20–1.63; p-value < 0.001) (4 trials; 779 patients). Diarrhea and dermatologic toxicities were statistically more frequent in patients receiving lapatinib than trastuzumab. The combination was associated with a higher rate of diarrhea than trastuzumab alone. No differences were observed regarding cardiac adverse events among patients receiving trastuzumab, lapatinib, or the combination.

Conclusion: These data support the superiority of a dual-HER2 inhibition for the treatment of HER2-positive breast cancer in the neoadjuvant setting. The direct comparison of trastuzumab and lapatinib demonstrated that lapatinib is inferior in terms of pCR and toxicity.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-18-18.

P3-07-34: Occult Metastasis in Sentinel Node: Should This Affect the Clinical Decision Making? A Systematic Review and Meta-Analysis

Background: The role of occult metastases (micrometastasis or isolated tumor cells [ITC]) in sentinel lymph nodes (SLN) remains a field of debate and speculation. The purpose of this systematic review and meta-analysis was to investigate the prognostic relevance of occult metastases in SLN.

Methods: We searched PubMed, without year or language restriction through June 2011, for studies on patients with invasive breast cancer with micrometastasis or ITC in the SLN and presented Hazard Ratios (HR) on Overall Survival (OS) / Disease-Free Survival (DFS) or enough data for HR-calculation. We used fixed- or random-effects meta-analyses, as appropriate, to calculate pooled estimates of HR. Results: Fifteen studies were considered eligible. Of those, 3 studies were excluded due to the lack of data for HR-calculation. Both the presence of ITC (5 studies; 1264 patients with ITC) and micrometastasis (10 studies; 1093 patients with micrometastasis) were associated with worse DFS (pooled HR 1.29, 95% Confidence Interval [CI]: 1.09−1.52, P-value = 0.002 for ITC, pooled HR 1.45, 95% CI: 1.28−1.64, P-value < 0.001 for micrometastasis). No significant differences were observed regarding OS neither for the presence of ITC (5 studies; 877 patients with ITC; pooled HR 1.20, 95% CI 0.98−1.46) nor for micrometastasis (8 studies; 1094 patients with micrometastasis; pooled HR 1.36, 95% CI: 0.98−1.88).

Conclusion: Based on the current evidence, it seems that the presence of occult metastasis in SLN is of prognostic significance in regard to DFS. However, the clinical significance of this difference is questioned since it cannot be translated into differences in OS. In anticipation of randomized trials aimed to evaluating the optimal management of each category of tumor burden within SLN, current evidence suggest a limited clinical significance of occult metastases in SLN.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-07-34.

Localization of disease-related PrP in Danish patients with different subtypes of prion disease

OBJECTIVE

The transmissible spongiform encephalopathies are characterized by vacuolization, neuronal loss, gliosis and deposition of a misfolded and Proteinase K resistant isoform of the prion protein (PrP(Sc)) in the central nervous system. METHODS MATERIALS AND PATIENTS: Paraffin-embedded tissue blot (PET-blot), immunohistochemistry (IHC) and Western blotting (WB) were combined to study the morphology and localization of disease related PrP in Danish patients with different subtypes of sporadic Creutzfeldt-Jakob disease, familiar Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker disease.

RESULTS AND CONCLUSION

There was a good morphological and anatomical concordance between what was found with PET-blot and IHC in all patients. In some specific cases, the PET-blot was superior to IHC in sensitivity. To our knowledge, this is the first report where PET-blot analysis is applied to hereditary forms of human transmissible spongiform encephalopathies and compared with sporadic cases of Creutzfeldt-Jakob disease.

Posttherapeutic (131)I SPECT-CT offers high diagnostic accuracy when the findings on conventional planar imaging are inconclusive and allows a tailored patient treatment regimen

PURPOSE

The purpose of this prospective study was to determine the diagnostic impact and influence on patient treatment of posttherapeutic (131)I SPECT-CT when the findings on planar posttherapeutic whole-body scintigraphy (ptWBS) were inconclusive.

MATERIALS AND METHODS

A total of 53 SPECT-CT scans were performed in 41 patients with thyroid cancer after high-dose (131)I therapy (2.944 to 7.526 GBq (131)I) because of diagnostic uncertainty on ptWBS. Physiological uptake in the salivary glands, gastric mucosa, gut, nasal mucosa, urinary tract and liver were considered to be normal. Any other foci of increased (131)I uptake, except iodine uptake clearly located in the thyroid bed, were considered to be abnormal. The data were evaluated on a lesion and a patient basis.

RESULTS

Regarding neck lesions, SPECT-CT provided a diagnostic impact in 26/90 lesions (28.9%) and confirmed the diagnosis in 64/90 lesions (71.1%). On a patient basis, SPECT-CT changed N status in 12/33 patients (36.4%), provided a diagnostic impact in 21/33 patients (63.6%) and led to a treatment change in 8/33 patients (24.2%). Regarding lesions distant from the neck, SPECT-CT confirmed the diagnosis in 62/71 lesions (87.3%) and had a diagnostic impact in 9/71 lesions (12.7%). On a patient basis, SPECT-CT changed M status in 4/19 patients (21.1%), had a diagnostic impact in 14/19 patients (73.7%) and led to a treatment change in 2/19 patients (10.5%). Considering all patients, SPECT-CT led to a treatment change in 10/41 patients (24.4%).

CONCLUSION

Integrated SPECT-CT is a useful tool, especially in cases of diagnostic uncertainty and helps to individualize patient management.

Guidelines for radioiodine therapy of differentiated thyroid cancer

INTRODUCTION

The purpose of the present guidelines on the radioiodine therapy (RAIT) of differentiated thyroid cancer (DTC) formulated by the European Association of Nuclear Medicine (EANM) Therapy Committee is to provide advice to nuclear medicine clinicians and other members of the DTC-treating community on how to ablate thyroid remnant or treat inoperable advanced DTC or both employing large 131-iodine ((131)I) activities.

DISCUSSION

For this purpose, recommendations have been formulated based on recent literature and expert opinion regarding the rationale, indications and contraindications for these procedures, as well as the radioiodine activities and the administration and patient preparation techniques to be used. Recommendations also are provided on pre-RAIT history and examinations, patient counselling and precautions that should be associated with (131)I iodine ablation and treatment. Furthermore, potential side effects of radioiodine therapy and alternate or additional treatments to this modality are reviewed. Appendices furnish information on dosimetry and post-therapy scintigraphy.

Is there a role for scintigraphic imaging of bone manifestations in Gaucher disease? A review of the literature

Gaucher disease is the most prevalent inherited, lysosomal storage disease and is caused by deficient activity of the enzyme beta-glucocerebrosidase. Bone and bone marrow alterations are frequent in the most prevalent non-neuronopathic form of Gaucher disease. Imaging of bone manifestations in Gaucher disease is performed by a variety of imaging methods, conventional X-ray and MRI as the most frequently and most important ones. However, different modalities of scintigraphic imaging have also been used. This article gives an overview on scintigraphic imaging with respect to bone manifestations in Gaucher disease discussing the advantages and limitations of scintigraphic imaging in comparison to other imaging methods.

Sentinel node SPECT-CT in breast cancer. Can we expect any additional and clinically relevant information?

The AIM of this study was to determine the additional value of SPECT/CT in sentinel node scintigraphy in breast cancer. Furthermore, it was our question to determine, whether the low-dose computed tomography component (LD-CT) can be used for axillary lymph node staging of clinically negative patients.

PATIENTS, METHODS

51 patients with invasive breast cancer <3 cm in diameter were included in our prospective investigation. SPECT/CT was performed on a dedicated scanner 30 minutes after subareolar injection of (99m)Tc-Nanocoll. Axillary staging with CT(LD) was performed using standard CT-criteria. SLN were allocated to an axillary level using SPECT alone and SPECT/CT. Additionally, the number of SLN on CT(LD) corresponding to the scintigraphic hot node was notified for each patient and compared to the number of SLN found with the gamma probe.

RESULTS

In 45/51 evaluable patients SLN could be localised in level I in 43 patients and in level II in two patients (all positive) using SPECT-CT, whereas a clear allocation could not be obtained by SPECT alone. The number of SLN was discrepant between SPECT and CT(LD) in 13/45 patients. The number of SLN detected with the gamma probe (n = 68) not significantly differed from the number of SLN detected by CT(LD) (n = 65) but was significantly higher than with SPECT (n = 51). CT(LD) yielded a sensitivity of 35.7%, a specificity of 83.9%, a positive predictive value (PPT) of 50%, a negative predictive value (NPV) of 74.3% and a diagnostic accuracy of 68.9% for axillary staging with CT(LD).

CONCLUSION

The additional information of SPECT/CT allows a more accurate characterization of the SN concerning size, depth and anatomical location. CT(LD) when performed during (99m)Tc-Nanocoll sentinel-SPECT/CT is not suitable for axillary staging in breast cancer patients with clinical negative axilla due to its low sensitivity and moderate specificity. Therefore, it does not influence the decision for SNB or ALND. The limited resolution of SPECT leads to an underestimation of the number of SLN compared to CT(LD) and the gamma probe.

Use of IgG avidity ELISA to differentiate acute from persistent infection with Salmonella Dublin in cattle

AIMS

To investigate whether an immunoglobulin (Ig)G avidity ELISA can be used to differentiate between acute and persistent infection with Salmonella (S.) Dublin in cattle. To determine whether the IgG isotype, IgG(1) and IgG(2) responses in acute and persistent infections differ.

METHODS AND RESULTS

Animals were selected from two herds with long-term infection (years) and two herds recently infected (<3 months). Forty-seven animals were categorized into groups based on the persistence of their antibody level in milk. Based on titre from two serial dilutions the avidity index (AI) was calculated for IgG (IgG-AI), IgG(1) (IgG(1)-AI) and IgG(2) (IgG(2)-AI). The mean IgG-AI for suspected carrier animals with either persistently high (group 1) or persistently high to medium high (group 2) antibody levels was significantly (P = 0.003) higher (32.1% and 38.4%) than for acutely infected animals (21.7% and 22.3%). The probability of being a suspect carrier was associated with IgG-AI, antibody level in the sample and age. However, the effect of age could be the result of a biased sample selection. Specificities and sensitivities were calculated at a range of cut-off values for IgG-AI and IgG(1)-AI. Overall, IgG(2)-AI was high compared with IgG(1)-AI, and there was no difference in IgG(2)-AI between infection groups. There was no difference in the ratio IgG(2):IgG(1) for acute and persistent infection groups.

CONCLUSIONS

Assuming that a persistently high antibody response is indicative of persistent infection with S. Dublin in cattle, it can be concluded that the IgG-AI can aid in differentiating between acute and long-term infection on herd level. However, for the test to be useful as an alternative tool to repeated sampling over time for detection of persistently infected carriers during control strategies in cattle herds, the test needs to be optimized and studied further in a larger sample of well-characterized infections in cattle. The affinity of IgG(2) is higher than IgG(1) early in the S. Dublin infection. There appears to be no difference in the IgG(2)-AI between the acute and chronic infection stages.

SIGNIFICANCE AND IMPACT OF THE STUDY

For decades the strategies for detection of persistently infected cattle in S. Dublin infected herds have involved repeated bacteriological culture of faecal samples or repeated antibody measurements over several months. Both methods are time consuming and costly, leaving a new method for detection of carrier animals based on a single sampling highly desirable. This study illustrates a tool, IgG-AI, which may prove useful, although more validation of the method is required before it is used in practice.

Receptor activator of nuclear factor kappaB ligand and osteoprotegerin in men with thyroid cancer

BACKGROUND

Suppressive thyroid hormone therapy is generally a lifelong treatment for patients with differentiated thyroid cancer (DTC). However, long-standing thyrotropin (TSH) suppression is a risk factor for osteoporosis. Osteoprotegerin (OPG) and receptor activator of nuclear factor kappaB ligand (RANKL) are central regulators of bone turnover. The aim was to analyze the effects of a suppressive thyroid hormone therapy in males with DTC on the OPG/RANKL system and on bone metabolism.

PATIENTS AND METHODS

The OPG and soluble RANKL (sRANKL) were determined in 40 men (mean age, 53.2 years) with DTC on suppressive thyroid hormone therapy (TSH; 0.053 +/- 0.037 mU L(-1), duration 5.7 +/- 4.4 years) and 120 healthy controls matched for age. The markers of bone metabolism were C-terminal telopeptide of type I collagen in serum (sCTx) and osteocalcin (OC).

RESULTS

The control group had OPG values (mean +/- SD) of 1.9 +/- 1.0 pmol L(-1) and sRANKL values of 0.40 +/- 0.62 pmol L(-1). In patients with DTC, results for OPG were 3.03 +/- 1.04 pmol L(-1) (P < 0.05) and for sRANKL were 0.13 +/- 0.16 pmol L(-1) (P < 0.05). The control group presented values for sCTx of 2669 +/- 1132 pmol L(-1) and for OC of 17.89 +/- 6.5 ng mL(-1). Patients with DTC on suppressive thyroid hormone therapy had increased sCTx values of 3810 +/- 2020 pmol L(-1) (P = 0.03) but comparable OC values of 19.21 +/- 7.67 ng mL(-1) (NS).

CONCLUSIONS

Suppressive thyroid hormone therapy in men with DTC increased bone degradation and induced significant changes in the OPG/RANKL system. These changes include, besides the risk of osteoporosis, possible negative effects on the vascular function and an increased risk of cardiovascular disease.

Seroprevalence of Toxoplasma gondii infection in goats and sheep in Zimbabwe

Seroprevalence rates of Toxoplasma gondii anti-antibodies in adult goats and sheep from different parts of Zimbabwe were determined. A total of 225 (67.9%) of the 335 serum samples tested were positive for anti-T. gondii IgG antibodies with the indirect fluorescent antibody test. There were differences in antibody seroprevalences among communal land goats from the different agro-ecological zones (Natural regions llb and III: 80 and 96.7%, respectively; Natural region IV: 65.9%; Natural region V: 45%; and Natural region III had a significantly higher seroprevalence than IV and V. The highest seroprevalences found in Natural regions II b and Ill are likely to be linked to the existence of more households and hence the possibility of a higher concentration of domestic cats that increases the chances of environmental contamination with their faeces harbouring T. gondii oocysts. The seroprevalence rate in sheep from a large commercial farm (10%) was significantly lower than that of sheep reared under the communal grazing system (80%). Overall, significantly higher proportions of seropositive animals had antibody titres of 1:50 (34.2% of 225) and 1:100 (44% of 225) as compared to the 9.8% and 12% with antibody titres of 1:200 and > or =1:400, respectively.

Cancer chemotherapy administered via hemodialysis fistulas

End-stage renal failure (ESRF) patients can develop cancer before or after kidney disease occurs. Cancer chemotherapy often needs to be administered via the sort of central venous catheter that is normally avoided in ESRF care. Three cases are presented in which ESRF patients received chemotherapy for cancer via existing hemodialysis fistulas, and the consequences of central venous access in a fourth patient are discussed.

Short-term Study of the Uptake of PrPSc by the Peyer's Patches in Hamsters after Oral Exposure to Scrapie

The disease-associated prion protein (PrP(Sc)) has been detected in the ileal Peyer's patches of lambs as early as one week after oral exposure to scrapie. In hamsters, the earliest reported time of PrP(Sc) detection in the Peyer's patches after oral exposure to scrapie is 69 days post-infection. To evaluate the acute uptake of inoculum and to investigate whether the Peyer's patches constitute the primary site of entry for scrapie after oral exposure, hamsters were each exposed orally to 1 ml of a 10% brain homogenate from hamsters in the terminal stage of infection with the 263 K strain of the scrapie agent. PrP(Sc) was demonstrated in the Peyer's patches only a few days after exposure, i.e., much earlier than previously reported. This study supports the view that the Peyer's patches constitute at least one of the primary entry sites of PrP(Sc) after oral exposure to scrapie.

Seroprevalence of Toxoplasma gondii infection in domestic pigs reared under different management systems in Zimbabwe

Serum samples from 474 domestic pigs (Sus scrofa) from Zimbabwe were tested for anti-Toxoplasma gondii IgG antibodies using the indirect fluorescent antibody test. The results showed that T. gondii infection is widespread in Zimbabwean pigs. Seroprevalence was lowest in fattening pigs from large and small-scale commercial farms that practise good hygiene (19.75% of 238) and highest in backyard scavenging pigs (35.71% of 70). Only 11.7% (11) of the 127 positive samples had titres of > or = 1:400 and nine (81.82%) of these 11 originated from pigs reared under poor hygienic conditions. A prevalence of 3.51% was found in the same group of fattening pigs using an indirect IgG enzyme-linked immunosorbent assay at the single serum dilution of 1:400. The serosurvey shows the importance of modern intensive husbandry systems in reducing the prevalences of T. gondii infection in domestic pigs.

Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis

CONTEXT

Plasma fibrinogen levels may be associated with the risk of coronary heart disease (CHD) and stroke.

OBJECTIVE

To assess the relationships of fibrinogen levels with risk of major vascular and with risk of nonvascular outcomes based on individual participant data.

DATA SOURCES

Relevant studies were identified by computer-assisted searches, hand searches of reference lists, and personal communication with relevant investigators.

STUDY SELECTION

All identified prospective studies were included with information available on baseline fibrinogen levels and details of subsequent major vascular morbidity and/or cause-specific mortality during at least 1 year of follow-up. Studies were excluded if they recruited participants on the basis of having had a previous history of cardiovascular disease; participants with known preexisting CHD or stroke were excluded.

DATA EXTRACTION

Individual records were provided on each of 154,211 participants in 31 prospective studies. During 1.38 million person-years of follow-up, there were 6944 first nonfatal myocardial infarctions or stroke events and 13,210 deaths. Cause-specific mortality was generally available. Analyses involved proportional hazards modeling with adjustment for confounding by known cardiovascular risk factors and for regression dilution bias.

DATA SYNTHESIS

Within each age group considered (40-59, 60-69, and > or =70 years), there was an approximately log-linear association with usual fibrinogen level for the risk of any CHD, any stroke, other vascular (eg, non-CHD, nonstroke) mortality, and nonvascular mortality. There was no evidence of a threshold within the range of usual fibrinogen level studied at any age. The age- and sex- adjusted hazard ratio per 1-g/L increase in usual fibrinogen level for CHD was 2.42 (95% confidence interval [CI], 2.24-2.60); stroke, 2.06 (95% CI, 1.83-2.33); other vascular mortality, 2.76 (95% CI, 2.28-3.35); and nonvascular mortality, 2.03 (95% CI, 1.90-2.18). The hazard ratios for CHD and stroke were reduced to about 1.8 after further adjustment for measured values of several established vascular risk factors. In a subset of 7011 participants with available C-reactive protein values, the findings for CHD were essentially unchanged following additional adjustment for C-reactive protein. The associations of fibrinogen level with CHD or stroke did not differ substantially according to sex, smoking, blood pressure, blood lipid levels, or several features of study design.

CONCLUSIONS

In this large individual participant meta-analysis, moderately strong associations were found between usual plasma fibrinogen level and the risks of CHD, stroke, other vascular mortality, and nonvascular mortality in a wide range of circumstances in healthy middle-aged adults. Assessment of any causal relevance of elevated fibrinogen levels to disease requires additional research.

Seroprevalence of Toxoplasma gondii infection in goats and sheep in Zimbabwe

Seroprevalence rates of Toxoplasma gondii anti-antibodies in adult goats and sheep from different parts of Zimbabwe were determined. A total of 225 (67.9 %) of the 335 serum samples tested were positive for anti-T. gondii IgG antibodies with the indirect fluorescent antibody test. There were differences in antibody seroprevalences among communal land goats from the different agro-ecological zones (Natural regions IIb and III: 80 and 96.7 %, respectively; Natural region IV: 65.9 %; Natural region V: 45 %; and Natural region III had a significantly higher seroprevalence than IV and V. The highest seroprevalences found in Natural regions II b and III are likely to be linked to the existence of more households and hence the possibility of a higher concentration of domestic cats that increases the chances of environmental contamination with their faeces harbouring T. gondii oocysts. The seroprevalence rate in sheep from a large commercial farm (10 %) was significantly lower than that of sheep reared under the communal grazing system (80 %). Overall, significantly higher proportions of seropositive animals had antibody titres of 1:50 (34.2 % of 225) and 1:100 (44 % of 225) as compared to the 9.8 % and 12 % with antibody titres of 1:200 and > 1:400, respectively.

Preliminary characterisation of Toxoplasma gondii isolates from Zimbabwe, with stage-specific monoclonal antibodies

Cell-culture-derived clones of eight Toxoplasma gondii isolates from Zimbabwe were characterised in IFAT with a panel of five monoclonal antibodies (mAb). Each clone had been established from a single murine brain cyst. The antibodies were bradyzoite-specific (4.3), tachyzoite-specific (4.25, 5.1 and anti-P(30)), or tachyzoite- and bradyzoite-specific (5.15). Their strong reactivity with the bradyzoite-specific mAb 4.3 and their weaker reactivity with the tachyzoite-specific 4.25, 5.1 and anti-P(30) indicated that all the isolates are probably of genetic type II. Each of the isolates reacted in the IFAT in a similar way to the Danish reference strain of T. gondii, SSI-119.

Longitudinal study of interferon-gamma, serum antibody and milk antibody responses in cattle infected with Mycobacterium avium subsp. paratuberculosis

During a 2-year study period, 252 animals from dairy herds infected with Mycobacterium avium subsp. paratuberculosis, and 119 animals from non-infected herds were subjected to repeated blood and faecal sampling. Animals were retrospectively grouped by infection status as infected, exposed (culture negative animals from infected herds), or non-infected animals, and by age, 12-23 months (1+ year), 24-35 months (2+ years), or 36 months and older (3+ years). Samples were collected for culture of faeces, assessment of interferon-gamma (IFN-gamma) secreted by M. paratuberculosis antigen stimulated whole-blood lymphocytes (IFN-gamma test), and measurement of antibody responses against M. paratuberculosis in serum and milk by an in-house absorbed ELISA. The IFN-gamma test diagnosed higher proportions of infected and exposed animals than the antibody ELISAs. The highest sensitivity of IFN-gamma test was in infected cattle of 2+ years of age. Receiver-operating characteristic (ROC) analyses supported the assumption that the IFN-gamma test had a better performance than antibody tests of animals of 1+ and 2+ years of age. However, for animals of 3+ years all tests performed equally well. Application of single sampling compared with repeated samplings showed better performance of the IFN-gamma test by repeated samplings, and the milk antibody ELISA in animals of 3+ years of age performed significantly better with repeated sampling compared with single sampling. In conclusion, the IFN-gamma test may be applied for screening of cattle of 1 and 2 years of age for exposure to M. paratuberculosis and the antibody ELISAs from 3 years of age.

Clinical Experience with a Commercially Available Negative Oral Contrast Medium in PET/CT

PURPOSE

To evaluate a commercially available negative oral contrast material for PET/CT.

MATERIAL AND METHODS

In a prospective series of 49 patients, Mukofalk, which is a vegetarian-based substance, was used as a negative oral contrast medium in whole body PET/CT studies. Mukofalk was administered during a time period of 1.5 hours before the examination. Quality of small bowl distension and eventual pathological tracer uptake in the intestine were evaluated.

RESULTS

Distension of the small bowel was excellent or good in 41 (85 %) and poor in 8 (15 %) patients. Mild tracer uptake in the small bowel was observed in 5 patients (10.2 %) and moderate uptake in another 2 patients (4 %). In none of these patients did the F-18 FDG uptake interfere with image interpretation.

CONCLUSION

Mukofalk can be used as a negative oral contrast medium in PET/CT studies.

Cross-sectional survey in pig breeding farms in Hesse, Germany: seroprevalence and risk factors of infections with Toxoplasma gondii, Sarcocystis spp. and Neospora caninum in sows

A cross-sectional survey was performed to estimate the prevalences of antibodies to Toxoplasma gondii (ELISA, IFAT), Sarcocystis spp. (ELISA, using S. miescheriana as antigen) and Neospora caninum (ELISA, immunoblotting) in sows from breeding farms in southern Hesse, Germany. A total of 2041 plasma samples of sows from 94 randomly selected farms was examined. Data on farm profiles, husbandry management and sows were collected by a questionnaire and exploratively analysed. For T. gondii the ELISA results agreed well with the results obtained by IFAT (kappa=0.71). Antibodies to T. gondii were detected by ELISA in 19% of the sows. Sixty-nine percent of the farms had at least one seropositive sow, and a within-farm seroprevalence of >or=50% was observed in 14% of all farms. The prevalence of anti-T. gondii antibodies was positively correlated with the age of sows. The within-herd seroprevalence was significantly higher in farms with reproductive disorders than in those without such problems. On the farm level, the farm type 'piglet production' (versus 'pedigree breeding' or 'farrow-to-finish') was the only risk factor associated with the presence of T. gondii-seropositive sows. Antibodies to Sarcocystis spp. were found in 29% of the sows. Seventy-two percent of the farms harboured at least one seropositive sow, and a within-farm seroprevalence of >or=50% was detected in 23% of all farms. The seroprevalence increased significantly with the age of sows. On the farm level, only the farm type 'piglet production' (versus 'pedigree breeding') and the replacement of sows by purchasing (versus raising on the own farm) were identified as risk factors for seropositivity. Antibodies to N. caninum were detected in one sow using both the screening ELISA and the confirmatory immunoblotting technique. This may indicate the first natural N. caninum infection in pigs.

The effect of colostrum on pigs pre-natally or post-natally exposed toSchistosoma japonicum

Pre-natal infection ofSchistosoma japonicumin pigs may prove to be a useful model in shedding light on human pre-natal schistosomiasis. This study describes the effects of immune colostrum on worm burdens, tissue egg counts, liver pathology and crude worm or egg antigen-specific IgG and IgA responses, in groups of pigs pre-natally, pre-natally+post-natally or post-natally exposed toS. japonicum. Results suggest that pre-natal exposure and immune colostrum did not affect the establishment of a post-natal challenge infection. However, immune colostrum seemed to increase the levels of septal fibrosis in pre-natally exposed pigs. These findings indicate that further investigations will prove valuable, elucidating the influence of the parasitological and immunological status of the sow, on pre-natally exposed pigs, and on the ability of these pigs to develop resistance againstS. japonicumlater in life.