The efficacy of sacituzumab govitecan and trastuzumab deruxtecan on stable and active brain metastases in metastatic breast cancer patients-a multicenter real-world analysis

BACKGROUND

Fifteen to thirty percent of all patients with metastatic breast cancer (MBC) develop brain metastases (BCBMs). Recently, the antibody-drug conjugates (ADCs) sacituzumab govitecan (SG) and trastuzumab deruxtecan (T-DXd) have shown to be highly effective in the treatment of MBC. However, there are only limited data whether these macromolecules are also effective in patients with BCBMs. We therefore aimed to examine the efficacy of SG and T-DXd in patients with stable and active BCBMs in a multicenter real-world analysis.

PATIENTS AND METHODS

Female patients with stable or active BCBMs who were treated with either SG or T-DXd at three breast centers in Germany before 30 June 2023 were included. As per local clinical praxis, chemotherapy efficacy was evaluated by whole-body computed tomography and cranial magnetic resonance imaging at baseline and at least every 3 months according to local standards. Growth dynamics of BCBMs were assessed by board-certified neuroradiologists.

RESULTS

Of 26 patients, with a median of 2.5 prior therapy lines in the metastatic setting (range 2-15), 12 (43%) and 16 (57%) patients received SG and T-DXd, respectively. Out of the 12 patients who received SG, 2 (17%) were subsequently treated with T-DXd. Five out of 12 (42%) and 5 out of 16 (31%) patients treated with SG and T-DXd, respectively, had active BCBMs at treatment initiation. The intracranial disease control rate was 42% [95% confidence interval (CI) 13% to 71%] for patients treated with SG and 88% (95% CI 72% to 100%) for patients treated with T-DXd. After a median follow-up of 12.7 months, median intracranial progression-free survival was 2.7 months (95% CI 1.6-10.5 months) for SG and 11.2 months (95% CI 7.5-23.7 months) for T-DXd.

CONCLUSIONS

SG and T-DXd showed promising clinical activity in both stable and active BCBMs. Further prospective clinical studies designed to investigate the efficacy of modern ADCs on active and stable BCBMs are urgently needed.

Mid-Term Outcomes of a Hybrid Approach Involving Open Surgery Plus TEVAR of the Descending Aorta in the Treatment of Complex Type A Dissection

OBJECTIVES

Type A aortic dissection with true lumen collapse and malperfusion downstream is associated with a devastating prognosis. This study compares the clinical outcomes of two operative strategies for this disease: hybrid approach of ascending aorta (and hemiarch replacement) supplemented with retrograde stenting of the descending aorta (thoracic endovascular aortic repair [TEVAR]) and standard ascending aorta (and hemiarch) replacement without stent placement.

METHODS

From January 1, 2016 to December 31, 2019, 81 patients with type A aortic dissection were studied. The hybrid technique was applied in 30 patients (group 1), while 51 patients received standard surgical repair (group 2). Patient demographics, clinical and operative findings, postoperative outcome, follow-up interventions, and mid-term survival were analyzed.

RESULTS

Baseline characteristics were similar among the groups, except that more preoperative malperfusion was evident in group 1. The postoperative incidence of visceral malperfusion (0 vs. 15.7%, p = 0.02) and low cardiac output syndrome requiring extracorporeal membrane oxygenation support (3.3 vs. 19.6%, p = 0.04) was significantly less in group 1. In-hospital mortality was also significantly lower in group 1 as in group 2 (13.3 vs. 33.3%, p = 0.04). At follow-up, the need for secondary endovascular stenting (3.3 vs. 7.8%, p = 0.65) and surgical aortic reintervention (6.7 vs. 2.0%, p = 0.55) was comparable. One-year, 2-year, and 3-year survival rates were 83.3, 83.3, and 62.5% in group 1, and 58.7, 58.7, and 52.6% in group 2 (p = 0.05), respectively.

CONCLUSION

The combination of open surgical replacement of the ascending aorta (and hemiarch) with TEVAR of the descending aorta for true lumen compromise is a feasible treatment option for patients with type A aortic dissection and is associated with a better perioperative outcome and improved mid-term survival rate.

Treatment of end-stage peripheral artery disease by Neuromodulation

BACKGROUND: Neuromodulation is a therapeutic option to improve limb salvage in end-stage peripheral arterial disease (PAD), but there is no consensus on indication for spinal cord stimulation (SCS) in PAD patients. OBJECTIVE: The aim of this study was to present end-stage PAD patient outcomes treated with SCS. METHODS: This study is a retrospective analysis based on a local prospective registry. Neuromodulation was performed there was: [1] no revascularisation option, [2) no septicaemia, [3) Rutherford stage 4–6. The primary endpoint of the study was limb salvage. Secondary endpoints were improvement in pain symptoms (assessed using a visual anlog scale/VAS) and improvement in walking distance. RESULTS: Limb salvage was reached in 30/34 patients (88%). Patients reported a significant reduction in pain on the 10-point VAS scale from baseline (median = 7.5, IQR = 7–8) to follow-up at 2 years (median = 0, IQR 0–2.75), p <  0.001. Walking distance also improved from preoperative (median = 50 m, IQR = 20–50 m) to follow-up at 2 years (median = 150 m, IQR 50–272 m), p <  0.001. RESULTS: SCS implantation in patients with end-stage PAD can enable limb salvage in a high percentage of cases and increase mobility due to pain reduction. The role of microcirculation in these improvements needs to be investigated in further studies.

Role of aorto(bi)femoral bypass in treatment of patients with critical limb threatening ischemia

PURPOSE

To analyse the long-term outcome of open aortic procedures in patients with critical limb threatening ischemia.

METHODS

Retrospective analysis of all patients with aortoiliac TransAtlantic Inter-Society Consensus II (TASC II), type D (TASC D) lesions extending to the femoral artery who underwent aortic bypass procedures for critical limb threatening ischemia (CLTI) or intermittent claudication (IC).

RESULTS

Over a period of 10 years, 87 patients with IC and 45 patients with CLTI received a total of 56 aortounifemoral and 76 aorto-bi-femoral bypass procedures. After 7 years, overall primary patency (82.2% [CLTI] vs. 80.5% [IC], p = .918) and overall secondary patency (88.9% [CLTI] vs. 88.5% [IC], p = .851) were similar between patients with CLTI and those with IC. Long-term-survival (66.7% vs. 71.3%, p = .356) as well as limb salvage (86.7% vs. 94.3%, p = .104) was considerably lower in the CLTI-group, but the difference was not statistically significant. In the subgroup analysis, patients with CLTI and ischemic lesions (Rutherford class 5-6) had the poorest outcome after 84 months, in terms of secondary patency (92.1% vs. 73.7%, p = .015), limb salvage (97.4% vs. 73.7%, p = .000), and long-term survival (75.0% vs. 26.3%, p = .000) compared to patients with IC. Multivariate analysis revealed significant associations for patients with Rutherford class 5-6 in terms of secondary patency (p = .037) and limb salvage (p = .015). There was a significant difference in primary patency between graft limbs with superficial femoral artery occlusion and graft limbs with patent superficial femoral artery (84.6% vs. 93.0%, p = .017).

CONCLUSIONS

Aortic bypass procedures can be used in the treatment of patients with CLTI. Moreover, results are satisfactory in patients with ischemic rest pain. However, less invasive treatments should be considered for patients with ischemic lesions.

Biosynthetic vascular graft: a valuable alternative to traditional replacement materials for treatment of prosthetic aortic graft infection?

Background and Aims:

To report the experience of a tertiary vascular surgery center using Omniflow II® biosynthetic vascular grafts for treatment of prosthetic aortic graft infection.

Materials and methods:

Retrospective analysis of all patients with prosthetic graft infections who underwent in situ aortic reconstruction using Omniflow II® grafts or other conduits between March 2015 and May 2017. Early and late mortality, perioperative complications, and reinfection rate were analyzed.

Results:

Sixteen patients (14 males, median age 68.5, range 57–89) with prosthetic aortic graft infection were treated at our center. Eight patients received an Omniflow II® biosynthetic graft, two patients silver-triclosan coated grafts, three patients bovine pericardial tube grafts, and three patients composite bovine pericardial tube grafts with Omniflow II® graft extensions. Perioperative complications occurred in seven patients (43.8%). Early mortality rate was 18.7% (n = 3). In addition, four patients died during follow-up after a median of 11 months (range 0–34 months). We did not observe any reinfections. Bypass grafts were patent in all patients. No major limb amputations were performed during follow-up.

Conclusion:

Treatment of prosthetic aortic graft infection with Omniflow II® vascular grafts is feasible. Graft material seems to have an excellent resistance to infection and might be a valuable alternative to traditional replacement materials. Especially long-term durability has to be continuously monitored and documented.

Equine parasite control and the role of national legislation - A multinational questionnaire survey

Experts recommend a change in the control of equine parasites across the world in order to adopt a surveillance-based approach utilizing parasite faecal egg counts (FEC). Several European countries have implemented prescription-only restrictions of anthelmintic usage by law, which is in stark contrast to US, where all anthelmintic products continue to be available over the counter. This study aimed to describe and compare equine parasite control strategies employed in Germany, Austria, the Netherlands, US, and Denmark. An invitation to participate in an online questionnaire survey was published on a large equine news website in each of the participating countries. The main focus of the study was on usage of FEC and anthelmintic treatment intensity in three different equine age groups; foals, 1-3 year-olds and >3 years old. A total of 3092 respondents participated in the study. Danish respondents used significantly more faecal analyses in their parasite control strategies than participants from the other four countries (p < 0.0001). Similarly, Danish participants administered significantly fewer anthelmintic treatments per horse per year (p < 0.0001) independent of the age of the horse, and had been using a selective treatment strategy for a significantly longer time period than their counterparts in other countries (p < 0.0001). Only minor differences were found between respondents from the other four countries. This is remarkable as both Austria and Germany have had prescription-only restrictions for 3-4 decades. Yet, their parasite control strategies were more similar to those employed by American respondents. The Netherlands had only recently introduced prescription-only restrictions by the time this survey was conducted which can explain why Dutch respondents were also similar to their American counterparts. Taken together, this study illustrates substantially different worm control strategies practiced in Denmark, and this difference cannot be explained by legislation alone.

Erhebungen zum Befall mit Ektoparasiten bei Neuweltkameliden

Ziel der vorliegenden Untersuchung war, die bei Neuweltkameliden vorkommenden Ektoparasiten auf einer breiten Basis zu erfassen. Material und Methoden: Von März 2008 bis Februar 2009 wurden 326 Lamas und Alpakas aus 13 Beständen im Zweimonats-Rhythmus adspektorisch sowie mittels verschiedener parasitologischer Nachweismethoden auf das Vorkommen von Ektoparasiten untersucht. Hierzu wurden 254 Ohrtupferproben, 254 Tesaabklatschpräparate und 27 Hautgeschabsel entnommen und ausgewertet. Ergebnisse: Es konnten Zecken (Ixodes ricinus), Kriebelmücken, Herbstgrasmilben (Trombicula autumnalis), Läuse (Microthoracicus sp.), Haarlinge (Bovicola sp.) sowie Haarbalg- und Räudemilben (Demodex sp., Sarcoptes scabiei, Chorioptes sp.) nachgewiesen werden. Schlussfolgerung und klinische Relevanz: Es ließ sich ein breites Spektrum von Ektoparasiten nachweisen. Dies ist insbesondere bei der Planung und Durchführung von Quarantänemaßnahmen zu berücksichtigen, um eine Einschleppung dieser Parasiten in den Bestand zu vermeiden.

Tick-borne fever caused by Anaplasma phagocytophilum in Germany

Four cows from North-West Germany have been diagnosed with tickborne fever (TBF) based on the demonstration of morulae in neutrophilic granulocytes in their blood smears, positive signals in real-time PCR specific for Anaplasma phagocytophilum using DNA extracted from their buffy coats, and demonstration of specific antibodies in their sera using a commercially available immunofluorescence assay. Clinical findings included high fever, decreased milk production, lower limb edema with stiff walking, eye and nasal discharge, and depression. These signs developed about a week after the animals had been brought to the pasture for the first time in their life. All cows recovered after 5–15 days, although DNA of A. phagocytophilum could be detected by real-time PCR up to 6 weeks after onset of the disease. Considering the known prevalences of A. phagocytophilum in ticks in Germany and its detection in dogs and horses, we think that underdiagnosing of TBE in cattle is highly likely. Therefore TBF should be taken into account as differential diagnosis in case of high fever and/or a sudden decrease in milk production in pastured animals.

Diagnostik und Therapie von Reisekrankheiten beim Hund

Durch die Mitnahme von Hunden in den Urlaub, bevorzugt in Länder des Mittelmeerraumes, nach Portugal oder auf die Kanarischen Inseln, und den Import von Tieren aus diesen Regionen werden Tierärzte in Deutschland immer häufiger mit den Reisekrankheiten Leishmaniose, Babesiose, Ehrlichiose und Dirofilariose konfrontiert. Dieser Artikel gibt einen Überblick über Diagnosemöglichkeiten und Therapie dieser Reisekrankheiten anhand von aktuellen Literaturangaben.

Für die Diagnostik von Reisekrankheiten ist die Erhebung eines gründlichen Vorberichtes eine entscheidende Hilfe. Neben einer sorgfältigen klinischen Untersuchung des Patienten stützt sich die Diagnose zwingend auf einen indirekten und/oder direkten Erregernachweis, der gegebenfalls mittels molekularbiologischer Nachweismethoden zu bestätigen ist. Die Identifikation noch am Tier vorhandener oder vom Tierbesitzer abgesammelter Zecken oder anderer Vektoren liefert einen wertvollen diagnostischen Hinweis. Folgende Wirkstoffe (Präparate) werden zur Therapie von Reisekrankheiten eingesetzt:

Leishmaniose: N-Methylglucamin-Antimoniat (Glucantime®, Merial) und/oder Allopurinol (Allopurinol ratiopharm®, Ratiopharm)

Babesia-canis-Infektionen: Imidocarbdiproprionat (Imizol®, Carbesia®, Schering-Plough Animal Health)

Ehrlichiose: Doxycyclin (Ronaxan®, Merial) und Imidocarbdiproprionat (Imizol®, Carbesia®, Schering-Plough Animal Health)

Dirofilariose

Melarsomindihydrochlorid (Immiticide®, Merial) zur Abtötung der Adultwürmer; Selamectin (Stronghold®, Pfizer) oder Milbemycinoxim und Praziquantel (Milbemax®, Novartis) oder Milbemycinoxim und Lufenuron (Program Plus®, Novartis) zur Beseitigung der Mikrofilarien Die häufigste durch Zecken übertragene Infektion bei Haustieren stellt in Deutschland die Lyme-Borreliose dar. Sie wird deshalb differenzialdiagnostisch mit einbezogen.

Vorläufige Ergebnisse von Tankmilch-Untersuchungen zum Fasciola-hepatica-Befall in bayerischen Milchviehherden

Gegenstand und Ziel: Da der koprologische Nachweis der Fasziolose beim Rind wenig sensitiv und sehr zeitaufwendig ist, wird sie diagnostisch oft nicht erfasst. Ziel der Studie ist, einen für Milchproben entwickelten ELISA-Test einzuführen, mit dem anhand von Tankmilchproben die Fasziolose auf Bestandsebene diagnostiziert und die flächenhafte Verbreitung von Fasciola hepatica in Bayern erfasst werden kann. Material und Methoden: Aus allen 80 Landkreisen Bayerns werden nach dem statistischen Zufallsprinzip je 80 Betriebe selektioniert. Die zwischen November und Mai entnommenen Tankmilchproben wurden mittels ELISA getestet. Ergebnisse: Die Verbreitung und Prävalenz der Fasziolose in den sechs bisher überprüften Landkreisen variiert sehr stark. Die voralpinen Regionen sind mit Prävalenzen zwischen 50 und 75% sehr stark betroffen, während im Flachland die Fasziolose ein sehr geringes Aufkommen (< 10%) zeigt. Der Hauptgrund scheint in der unterschiedlichen Haltungsform zu liegen. Schlussfolgerungen: Der Nachweis von F.-hepatica-Antikörpern in Tankmilchproben mittels ELISA lässt sich methodisch sehr gut realisieren. Dank seiner hohen Spezifität und Sensitivität ist der Test ein einfaches Hilfsmittel bei der gezielten Leberegelbekämpfung auf Bestandsebene oder für großflächige Bekämpfungs- oder Überwachungsprogramme. Klinische Relevanz: Die serologische Untersuchung ist für die klinische Beurteilung empfehlenswert und kann in Zukunft vermehrt für die Diagnostik angefordert werden.

Granulocytic anaplasmosis in 63 dogs: clinical signs, laboratory results, therapy and course of disease

OBJECTIVES

To describe the clinical signs, laboratory results, therapy and course of disease in dogs with canine granulocytic anaplasmosis in which co-infections had been excluded.

METHODS

Medical records of dogs naturally infected with Anaplasma phagocytophilum were retrospectively evaluated with regard to clinical signs and laboratory abnormalities at the time of presentation, therapy and course of disease.

RESULTS

Nine hundred and seventy-four dogs with clinical signs suspicious for canine granulocytic anaplasmosis were tested for A. phagocytophilum DNA by modified real-time PCR; 72 dogs had a positive result. Nine of the positive dogs were excluded from further evaluation due to other diseases or lack of data. The most common clinical signs in the 63 A. phagocytophilum-positive dogs included in the study were lethargy and reduced activity (83%), fever (67%) and inappetence (63%). Thrombocytopenia was the most common laboratory abnormality (86%), followed by increased liver enzyme activities and hyperbilirubinaemia (77%), anaemia (70%), hypoalbuminaemia (62%) and leucocytosis (27%). Of 36 thrombocytopenic dogs tested for platelet-bound antibodies, 44% were positive. Of the 63 infected dogs, 59 (97%) recovered, two dogs died (epileptic seizures and immune-mediated haemolytic anaemia) and two were lost to follow-up.

CLINICAL SIGNIFICANCE

In areas where it is endemic, canine granulocytic anaplasmosis should be considered as a potential cause of acute nonspecific clinical signs or immune-mediated disease if tick exposure cannot be excluded.

Trends in health surveillance and joint service delivery for pastoralists in West and Central Africa

In most sub-Saharan African countries, pastoralism represents an important economic resource and contributes significantly to national growth; however, challenges remain, particularly in providing social services to pastoralists (especially health and education) and in avoiding conflict with local sedentary communities and local authorities. All of this takes place while pastoralists try to maintain their mobile lifestyle within a rapidly changing ecosystem. Transdisciplinary approaches, such as 'One Health', which covers both human and animal health, have proven effective in delivering services and reaching mobile pastoralists in remote areas. The pastoralist way of life could be described as being linked to both their livestock and their environment, which makes social science an important element when researching the delivery and adaptation of social services to pastoralists. Early or pre-diagnostic detection of emerging and endemic infectious disease remains a vital aspect of health surveillance targeted at preventing further transmission and spread. Community-based syndromic surveillance, coupled with visual mobile phone technology, adapted to the high levels of illiteracy among nomads, could offer an alternative to existing health surveillance systems. Such an approach could contribute to accelerated reporting, which could in turn lead to targeted intervention among mobile pastoralists in sub-Saharan Africa. Although considerable efforts have been made towards integrating mobile pastoralists into social services, obstacles remain to the adoption of a clear, specific and sustainable policy on pastoralism in sub-Saharan Africa.

Inhibition of prenylated KRAS in a lipid environment

RAS mutations lead to a constitutively active oncogenic protein that signals through multiple effector pathways. In this chemical biology study, we describe a novel coupled biochemical assay that measures activation of the effector BRAF by prenylated KRAS^G12V in a lipid-dependent manner. Using this assay, we discovered compounds that block biochemical and cellular functions of KRAS^G12V with low single-digit micromolar potency. We characterized the structural basis for inhibition using NMR methods and showed that the compounds stabilized the inactive conformation of KRAS^G12V. Determination of the biophysical affinity of binding using biolayer interferometry demonstrated that the potency of inhibition matches the affinity of binding only when KRAS is in its native state, namely post-translationally modified and in a lipid environment. The assays we describe here provide a first-time alignment across biochemical, biophysical, and cellular KRAS assays through incorporation of key physiological factors regulating RAS biology, namely a negatively charged lipid environment and prenylation, into the in vitro assays. These assays and the ligands we discovered are valuable tools for further study of KRAS inhibition and drug discovery.

Detection of Strongylus vulgaris in equine faecal samples by real-time PCR and larval culture - method comparison and occurrence assessment

Background

Strongylus vulgaris has become a rare parasite in Germany during the past 50 years due to the practice of frequent prophylactic anthelmintic therapy. To date, the emerging development of resistance in Cyathostominae and Parascaris spp. to numerous equine anthelmintics has changed deworming management and the frequency of anthelmintic usage. In this regard, reliable detection of parasitic infections, especially of the highly pathogenic S. vulgaris is essential. In the current study, two diagnostic methods for the detection of infections with S. vulgaris were compared and information on the occurrence of this parasite in German horses was gained. For this purpose, faecal samples of 501 horses were screened for S. vulgaris with real-time PCR and an additional larval culture was performed in samples of 278 horses. A subset of 26 horses underwent multiple follow-up examinations with both methods in order to evaluate both the persistence of S. vulgaris infections and the reproducibility of each diagnostic method.

Results

The real-time PCR revealed S. vulgaris-DNA in ten of 501 investigated equine samples (1.9%). The larval culture demonstrated larvae of S. vulgaris in three of the 278 samples (1.1%). A direct comparison of the two methods was possible in 321 samples including 43 follow-up examinations with the result of 11 S. vulgaris-positive samples by real-time PCR and 4 S. vulgaris-positive samples by larval culture. The McNemar’s test (p-value = 0.016) revealed a significant difference and the kappa values (0.525) showed a moderate agreement between real-time PCR and larval culture.

Conclusions

The real-time PCR detected a significantly higher proportion of positives of S. vulgaris compared to larval culture and should thus be considered as a routine diagnostic method for the detection of S. vulgaris in equine samples.

Azaindoles as Zinc-Binding Small-Molecule Inhibitors of the JAMM Protease CSN5

CSN5 is the zinc metalloprotease subunit of the COP9 signalosome (CSN), which is an important regulator of cullin-RING E3 ubiquitin ligases (CRLs). CSN5 is responsible for the cleavage of NEDD8 from CRLs, and blocking deconjugation of NEDD8 traps the CRLs in a hyperactive state, thereby leading to auto-ubiquitination and ultimately degradation of the substrate recognition subunits. Herein, we describe the discovery of azaindoles as a new class of CSN5 inhibitors, which interact with the active-site zinc ion of CSN5 through an unprecedented binding mode. The best compounds inhibited CSN5 with nanomolar potency, led to degradation of the substrate recognition subunit Skp2 in cells, and reduced the viability of HCT116 cells.

The Influence of Preoperative Aneurysmal Thrombus Quantity and Distribution on the Development of Type II Endoleaks with Aneurysm Sac Enlargement After EVAR of AAA

PURPOSE

To determine the influence of preoperative aneurysmal thrombus quantity and distribution on the development of type II endoleak with aneurysm sac enlargement after endovascular aneurysm repair (EVAR).

MATERIALS AND METHODS

We retrospectively analyzed the pre- and postoperatively performed CT scans of 118 patients who had follow-up imaging for at least 1 year after EVAR available. We assessed preoperative thrombus perimeter (T Peri), diameter (T Dia), cross-sectional area (T CSA), and volume (T Vol). The preoperative thrombus distribution was classified into no thrombus, semilunar-shaped (anterior, right side, left side, posterior) thrombus, and circumferential type thrombus. The number of preoperative patent aortic side branches (ASB) was identified. Endpoint was type II endoleak with aneurysm volume (A Vol) increase of ≥5 % during follow-up.

RESULTS

During follow-up (2 years, range 1-9 years), 17 patients with type II endoleak had significant A Vol increase. Less preoperative T Peri, T Dia, T CSA, and T Vol were associated with A Vol increase. A circumferential thrombus distribution significantly protected against aneurysm enlargement (p = 0.028). The variables with the strongest significance for A Vol increase were preoperative T Vol/A Vol ratio (OR 0.95; p = 0.037) and number of patent ASB (OR 3.52; p < 0.001).

CONCLUSION

A low preoperative T Vol/A Vol ratio and a high number of patent ASB were associated with aneurysm sac enlargement after EVAR.

Ultrasound diagnostics of renal artery stenosis: Stenosis criteria, CEUS and recurrent in-stent stenosis

Background and purpose

As a non-invasive, side effect-free and cost-effective method, ultrasonography represents the method of choice for the diagnosis of renal artery stenosis. Four different criteria in total, including two direct criteria in peak systolic velocity (PSV) and renal aortic ratio (RAR) and two indirect criteria in resistance index (RI) and acceleration time (AT) for the measurement of relevant renal artery stenosis are described, each demonstrating highly variable accuracy in studies. Furthermore, there is controversy over the degree beyond which stenosis becomes therapeutically relevant and which ultrasound PSV is diagnostically relevant in terms of stenosis grading.

Material and methods

This article gives a critical review based on a selective literature search on measurement methodology and the validity of ultrasound in renal artery stenosis. A critical evaluation of methods and a presentation of measurement principles to establish the most precise measurement method possible compared with the gold standard angiography, as well as an evaluation of the importance of computed tomography angiography (CTA) and magnetic resonance angiography (MRA).

Results and conclusions

The PSV provides high sensitivity and specificity as a direct measurement method in stenosis detection and grading. Most studies found sensitivities and specificities of 85–90 % for > 50 % stenosis at a PSV > 180–200 cm/s in ROC curve analysis. Other methods, such as the ratio of the PSV in the aorta to the PSV in the renal artery (RAR) or indirect criteria, such as side to side differences in RI (dRI) or AT can be additionally used to improve accuracy. Contrast-enhanced ultrasound improves accuracy by means of echo contrast enhancement. Although in the past only high-grade stenosis was considered relevant for treatment, a drop in pressure of > 20 mmHg in > 50 % stenosis (PSV 180 cm/s) is classified as relevant for increased renin secretion. Stenosis in fibromuscular dysplasia can be reliably graded according to the continuity equation. Although the available studies on the grading of in-stent restenosis are the subject of controversy, there is a tendency to assume higher cut-off values for PSV and RAR. Whilst MRA and CTA demonstrate an accuracy of > 90 %, this is at the cost of possible side effects for patients, particularly in the case of pre-existing renal parenchymal damage.

Additional online material

This article includes two additional video sequences on visualizing renal artery stenosis. This supplemental material can be found under: dx.doi.org/10.1007/s00772-015-0060-3

Ultrasound diagnostics of the abdominal aorta: English version

BACKGROUND AND OBJECTIVES

The ideal method for screening investigations is one which is as free as possible from side effects, is easily learnt, and can therefore be broadly used to detect abdominal aortic aneurysms (AAA) with a high degree of certainty. Although ultrasonography fulfils these criteria, the measurement method is not standardized. Different measurement methods are used in ultrasonography as well as in computed tomography (CT) studies and the measurement method is actually described sufficiently in only 57 % of cases.

METHODS

This article provides a critical review of the current literature on measurement methods and the validity of ultrasonography for the determination of aortic diameter, particularly in AAA, and presents the measurement principles for making measurements as precisely as possible.

RESULTS AND CONCLUSION

The most precise determination of aortic diameter is carried out by electrocardiogram (ECG) gating according to the leading-edge method with orthogonal slicing. Within the framework of screening investigations, sufficient measurement precision can be achieved by adherence to orthogonal slicing. Using these standardized measurement methods, ultrasonography shows valid and reproducible results even compared with CT and is the method of choice in screening investigations for AAA.

Abstract B38: Inhibiting mutated KRAS, a broken switch of effector pathways

Mutated forms of KRAS are no longer able to switch effectors between “on” and “off” states. It is known that the function of KRAS is controlled by key parts in the C-terminus, including six consecutive lysines, a terminal prenyl moiety and a terminal carboxymethyl functional group. We set out to discover compounds which would inhibit the function of mutated KRAS as an activator for effectors. This campaign yielded several compounds that blocked biochemical and cellular functions of KRAS with low micromolar activity while not affecting markers outside of KRAS pathways in cells. In order to understand the mode of binding of these compounds to KRAS, we generated different forms of the protein, including unprenylated truncated and fully processed full-length protein. NMR studies with truncated protein (amino acids 1-169) identified a site at which compound binding stabilized the inactive conformation of KRAS. This site is located adjacent to switch-II and is similar to sites described by others. The Kd determined for this binding event is almost 3 orders of magnitude higher than the IC50 and EC50 values measured in biochemical and cellular assays. In order to understand this difference, we developed a biophysical assay using the Fortebio system which enabled binding studies in a system with full-length prenylated protein in the presence of lipids, to match the context of the biochemical and cellular assays. Micromolar binding to the full-length prenylated KRAS protein was observed in the Fortebio assay and binding was not observed in the absence of prenylation, consistent with the near millimolar Kd observed by NMR for truncated KRAS. Curiously, similar micromolar binding was seen to a peptide derived from the C-terminus of KRAS (amino acids 168-185) with and without prenyl modification while related compounds that do not bind to the full-length prenylated KRAS also do not bind to these peptides. It is still unclear whether binding to the terminal peptide in lipid context is related to the binding site adjacent to switch-II. From a drug discovery perspective, it remains to be confirmed whether current inhibitors can be optimized.

Citation Format: Johanna Jansen, Wolfgang Jahnke, Susan Fong, Laura Tandeske, Charles Wartchow, Keith Pfister, Tatiana Zavorotinskaya, Anke Blechschmidt, Dirksen Bussiere, Yumin Dai, Jeff Dove, Eric Fang, David Farley, Jean-Michel Florent, John Fuller, Simona Gokhin, Alvar Gossert, Mohammad Hekmat-Nejad, Chrystèle Henry, Julia Klopp, Bill Lenahan, Andreas Lingel, Arndt Meyer, Jamie Narberes, Gwynn Pardee, C Gregory Paris, Savithri Ramurthy, Paul Renhowe, Sebastien Rieffel, Kevin Shoemaker, Sharadha Subramanian, Tiffany Tsang, Stephania Widger, Armin Widmer, Isabel Zaror, Stephen Hardy. Inhibiting mutated KRAS, a broken switch of effector pathways. [abstract]. In: Proceedings of the AACR Special Conference on RAS Oncogenes: From Biology to Therapy; Feb 24-27, 2014; Lake Buena Vista, FL. Philadelphia (PA): AACR; Mol Cancer Res 2014;12(12 Suppl):Abstract nr B38. doi: 10.1158/1557-3125.RASONC14-B38

Ocular color-coded sonography - a promising tool for neurologists and intensive care physicians

Ocular color-coded duplex sonography (OCCS), when performed within the safety limits of diagnostic ultrasonography, is an easy noninvasive technique with high potential for diagnosis and therapy in diseases with raised intracranial pressure and vascular diseases affecting the eye. Despite the capabilities of modern ultrasound systems and its scientific validation, OCCS has not gained widespread use in neurological practice. In this review, the authors describe the technique and main parameter settings of OCCS systems to reduce potential risks as thermal or cavitational effects for sensitive orbital structures. Applications of OCCS are the determination of intracranial pressure in emergency medicine, and follow-up evaluations of idiopathic intracranial hypertension and ventricular shunting by measuring the optic nerve sheath diameter. A diameter of 5.7 - 6.0 mm corresponds well with symptomatically increased intracranial pressure (> 20 cmH2O). OCCS also helps to discriminate between different etiologies of central retinal artery occlusion - by visualization of a "spot sign" and Doppler flow analysis of the central retinal artery - and aids the differential diagnosis of papilledema. At the end perspectives are illustrated that combine established ultrasound methods such as transcranial color-coded sonography with OCCS.

Outcomes of fenestrated/branched endografting in post-dissection thoracoabdominal aortic aneurysms

OBJECTIVES

Fenestrated/branched thoracic endovascular repair (F/Br-TEVAR) is increasingly applied for atherosclerotic thoracoabdominal aortic aneurysm (TAAA); however, use in post-dissection TAAAs is still very limited. Experience with F/Br-TEVAR in the treatment of post-dissection TAAA is presented.

METHODS

Data were analysed from prospectively maintained databases including all patients with post-dissection TAAAs that underwent F/Br-TEVAR within the period January 2010 to July 2013 in two vascular institutions. Evaluated outcomes included initial technical success, operative mortality and morbidity, late survival, endoleak, aneurysm diameter regression, renal function, and reintervention during follow-up (FU).

RESULTS

A total of 31 patients (25 male, mean age 65 ± 11.4 years) were treated. Technical success was 93.5% and 30-day mortality 9.6%. Temporary spinal cord ischaemia occurred in four (12.6%) patients, with no case of permanent paraplegia. Mean FU was 17.0 ± 10 months. There were seven late deaths, all aneurysm unrelated. Estimated overall survival rates were 83.9 ± 6.7, 76.4 ± 7.9 and 71.6 ± 8.7% at 6, 12, and 18 months, respectively. Impairment of renal function occurred in two (6.4%) patients. Endoleaks were diagnosed in 12 patients during FU, including six type IB endoleaks and six type II endoleaks. Reintervention was required in seven (22.5%) patients. Mean aneurysm sac regression was 9.3 ± 8.7 mm, with a false lumen thrombosis rate of 66.7% and 88.2% for patients with a FU longer than 6 and 12 months respectively.

CONCLUSIONS

F/Br-EVAR is feasible for patients with a post-dissection TAAA. Although associated with additional technical challenges, and a significant need for reintervention, it leads to favourable aneurysm morphologic changes, and may play a more prominent role in the future for this type of pathology if long-term results confirm the good initial outcome.

Inhibition of Photosystem II by UV-B-Radiation

The effect of UV-B-radiation on PSII activity of spinach chloroplasts was analyzed by measuring the integrity of the herbicide-binding protein (HBP 32), by measurement of fluorescence induction in the presence of Diuron (DCMU), and by mathematical analysis of the fluorescence induction curves. It was shown that UV-B inactivates the PSII α-centers but not PSII β-centers. However, the possibility cannot be excluded that in addition the donor site of PSII near the reaction center is attacked by UV-B-radiation.

Cross-protection between geographically distinct Anaplasma marginale isolates appears to be constrained by limited antibody responses

The rickettsia Anaplasma marginale causes the haemolytic disease bovine anaplasmosis, an economic problem in tropical and subtropical areas worldwide. The closely related but less pathogenic Anaplasma centrale is commonly used as a live vaccine to prevent anaplasmosis, but it can only be produced from infected blood. UFMG1 is a low pathogenic Brazilian strain of A. marginale, which has been shown to protect cattle against a high pathogenic Brazilian isolate. As UFMG1 can be grown in tick cells, the strain was proposed as a possible cell culture-derived vaccine. We have evaluated whether UFMG1 could protect cattle against a geographically distant heterologous strain, using A. centrale vaccination as a standard for comparison. Trial calves were infected with UFMG1, A. centrale or PBS. UFMG1-infected animals were more symptomatic than those infected with A. centrale, but none required treatment. All calves were then challenged with the Israeli A. marginale Gonen strain (one of the most prevalent strain in Israel). The A. centrale group had the mildest symptoms, while UFMG1 and control groups both had a more severe response. Nevertheless, the challenge did not cause life-threatening disease in any group. Animals infected with A. centrale had a significantly higher IgG response than UFMG1, when measured in an ELISA against initial bodies from their homologous strain or Gonen. The level of cross-reactivity of the response to initial infection correlated significantly with reduced symptoms after challenge. In conclusion, UFMG1 had limited effect in preventing disease by the geographically distant heterologous Gonen strain. While the low pathogenicity of the Gonen strain in this trial makes it impossible to conclusively state that UFMG1 would have given no protective effect against more serious disease, the comparatively low IgG response to UFMG1 suggests it would not have been as effective as A. centrale.

[Control of bovine hypodermosis in Switzerland; looking back]

For many years, hypodermosis control - which started in the 1920's - was unsatisfactory, partly due to a lack of efficacy or a too high toxicity of the available products. An improved control became possible with the introduction (1957) of the organophosphate Metrifonate (Neguvon®, Bayer AG). Subsequent large-scale campaigns according to the Federal Ordinance on epizootic diseases (1967) quite reduced hypodermosis in Switzerland. However, due to a limited use of the product (only young and alpine-grazing cattle were allowed to be treated, administratively indicated maximum dose, side-effects) and its incomplete efficacy, a full control was not possible. The decision to maintain hypodermosis as a "notifiable" disease then allowed further epidemiological studies. In 2000/2001 a concerted action in close cooperation with the cantonal veterinarians allowed a consequent and systematic treatment of all cattle in all endemic areas by the large-scale use of Eprinomectin (Eprinex®, Merial Inc.) for dairy cattle and of Ivermectin (Merial Inc.) as microdose "off-label" for young cattle has led to a rapid and sustainable success.

[The significance of contrast-enhanced ultrasound in vascular surgery]

BACKGROUND

Vascular contrast-enhanced ultrasound (CEUS) is a special ultrasound application without the harmful side effects of nephrotoxicity and radiation exposure. CEUS can be used for advanced diagnosis of carotid stenosis and follow-up checks of endovascular repair of abdominal aortic aneurysms (EVAR). Low-flow phenomenon in peripheral vascular disease can easily be detected by enhanced colour-coded duplex sonography (CCDS).

METHODS

The technical requirements of CEUS are explained here for the aorta, carotid, and peripheral arteries. The benefits and risks compared to computed tomography (CT), magnetic resonance (MR) and angiography are evaluated. Based on a selective review of the literature and the authors' personal experiences, CEUS is recommended for routine surveillance after EVAR.

RESULTS

CEUS is a safe method using SonoVue® (Bracco) as the only approved agent for vascular examination. Special equipment and training is necessary. In prospective studies and meta-analyses the detection and characterisation of endoleaks is comparable to that of CT imaging. Neovascularisation as a sign of carotid plaques at risk can be seen without the need for invasive treatment. Imaging of crural vessels with enhanced CCDS is a promising but rarely needed option in diabetic and renally insufficient patients.

CONCLUSION

CEUS in vascular medicine should be performed prior to other methods to avoid nephrotoxic contrast agents for the patients, especially in follow-up checks after EVAR. The time and effort required are still limiting its practical breakthrough.