Anatomically constrained tractography facilitates biologically plausible fiber reconstruction of the optic radiation in multiple sclerosis

Diffusion-weighted magnetic resonance imaging (dMRI) enables the microstructural characterization and reconstruction of white matter pathways in vivo non-invasively. However, dMRI only provides information on the orientation of potential fibers but not on their anatomical plausibility. To that end, recent methodological advances facilitate the effective use of anatomical priors in the process of fiber reconstruction, thus improving the accuracy of the results. Here, we investigated the potential of anatomically constrained tracking (ACT), a modular addition to the tractography software package MRtrix3, to accurately reconstruct the optic radiation, a commonly affected pathway in multiple sclerosis (MS). Diffusion MRI data were acquired from 28 MS patients and 22 age- and sex-matched healthy controls. For each participant, the optic radiation was segmented based on the fiber reconstruction obtained using ACT. When implementing ACT in MS, it proved essential to incorporate lesion maps to avoid incorrect reconstructions due to tissue-type misclassifications in lesional areas. The ACT-based results were compared with those obtained using two commonly used probabilistic fiber tracking procedures, based on FSL (FMRIB Software Library) and MRtrix3 without ACT. All three procedures enabled a reliable localization of the optic radiation in both MS patients and controls. However, for FSL and MRtrix3 without ACT it was necessary to place an additional waypoint halfway between the lateral geniculate nucleus and the primary visual cortex to filter out anatomically implausible tracks. In the case of ACT, the results with and without an additional waypoint were virtually identical, presumably because the employed anatomical constraints already prevented the occurrence of the most implausible tracks. Irrespective of the employed tractography procedure, increased diffusivity and decreased anisotropy were found in the optic radiation of the MS patients compared to the controls.

•

Anatomical constraints improve tractography of the optic radiation in MS.

•

In MS, lesion mapping is essential to implement sensible anatomical constraints.

•

Patients showed increased diffusivity and decreased anisotropy in the OR.

Gut microbiota of the European Brown Hare (Lepus europaeus)

Diseases of the gastrointestinal tract due to changes in the bacterial flora have been described with increasing incidence in the European brown hare. Despite extensive demographic and phylogeographic research, little is known about the composition of its gut microbiota and how it might vary based on potential environmental or host factors. We analysed the intestinal and faecal microbiota of 3 hare populations by Illumina MiSeq 16S rRNA gene amplicon sequencing. The phyla and OTU abundance composition differed significantly between intestinal and faecal samples (PERMANOVA: P = 0.002 and P = 0.031, respectively), but in both sample types Firmicutes and Bacteroidetes dominated the microbial community composition (45.51% and 19.30% relative abundance). Intestinal samples contained an enrichment of Proteobacteria compared with faecal samples (15.71-fold change, P < 0.001). At OTU level, a significant enrichment with best BLAST hits to the Escherichia-Shigella group, Eubacterium limosum, Sphingomonas kyeonggiensis, Flintibacter butyricus and Blautia faecis were detected in intestinal samples (P < 0.05). In our statistical model, geographic location and possibly associated environmental factors had a greater impact on the microbiota composition than host factors. Population had a significant effect on the composition of abundant intestinal and faecal OTUs, and on the abundance of potential pathogenic bacteria of the family Enterobacteriaceae, regularly associated with intestinal dysbiosis in hares, in faecal samples. Our study is the first to describe the microbiota in brown hares and provides a foundation to generate hypothesis aiming to test the role of gut health in population fluctuations of the species.

Abstract P1-17-07: Cancer management and outcome of very young non-pregnant patients with breast cancer diagnosed at 40 years or younger– GBG 29

Introduction

Breast cancer diagnosed in young women who are 40 years (yrs) or younger is a relatively rare disease. However, it represents the most common cause of cancer-related deaths in this age-group. Furthermore, young age at diagnosis is associated with an increased risk of recurrence and worse survival. To date, general concepts concerning oncological cancer management should be driven by clinicopathological tumor characteristics and should adhere to standardized protocols for patients in general, but little is known about the oncological cancer treatment and outcome of this very young women in today's clinical practice.

Patients and Methods

The breast cancer in pregnancy registry study (BCP/GBG29/BIG 03-02) is a multicenter, international, observational study. BCP was established to investigate the oncological management and outcome of breast cancer in pregnancy. Since 2014 non-pregnant patients who are 40 yrs or younger are eligible if diagnosed with histological confirmed invasive breast cancer, independent of the type of treatment as control cohort. All patients received oncological treatment according to local standards. In this study the following endpoints will be analyzed descriptively for the young non-pregnant women cohort: breast cancer staging at diagnosis, biological characteristics of breast cancer at diagnosis, diagnostic procedures, treatment modalities, toxicity, pathological complete response after neoadjuvant chemotherapy, disease-free survival and overall survival.

Results

From February 2014 until June 2018, 969 non-pregnant patients ≤40 yrs have been registered. The median age at diagnosis was 35 yrs (range 19-40). Overall, 90.1% of patients had a stage T1-2 at diagnosis and 67.1% of patients had negative lymph nodes. 86.7% of tumors were invasive ductal carcinomas and 4.1% lobular carcinomas. Grading (G) 3 was reported in 55.5%. 26.6% of tumors were luminal A-like (ER- and/or PgR-positive, HER2-negative, G1-2), 40.0% luminal B-like (ER- and/or PgR-positive, HER2-negative, G3 or ER- and/or PgR-positive, HER2-positive, any G), 7.7% HER2 positive non-luminal-like, and 25.7% triple negative breast cancers. 3.8% of young non-pregnant patients had metastatic disease at primary diagnosis.

Conclusion

This registry comprises a large cohort of young non-pregnant patients with breast cancer diagnosed at the age of 40 yrs or younger and provides important data about a modern breast cancer treatment as well as oncological outcome in this setting of young women. Further results including oncological management, toxicity, and survival will be presented at the meeting.

Citation Format: Seiler S, Schmatloch S, Reinisch M, Neunhöffer T, Schmidt M, Bechtner C, Marmé F, Wagner M, Möbus V, Reimer T, Kleine-Tebbe A, Sinn B, Stickeler E, Untch M, Janni W, Seither F, Loibl S. Cancer management and outcome of very young non-pregnant patients with breast cancer diagnosed at 40 years or younger– GBG 29 [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-17-07.

Investigations on potential methods for the long-term monitoring of the state of fuel elements in dry storage casks

Extended dry storage of spent nuclear fuel is a relevant issue in many countries operating nuclear power plants. Beside regulatory and security aspects there are questions with respect to the long-term integrity of the spent fuel as this is of relevance for final transportation and reloading to final waste repository casks. Within the frame of the BMWi project DCS-MONITOR, we investigate the potentials of different methods for non-intrusive monitoring of dry cask storage containers with spent nuclear fuel. These are thermography, radiation-based methods, and acoustic methods. For all of them we study the sensitivity and cross-sensitivity with respect to defined changes in the nuclear fuel distribution inside the containers. The analyses are mainly based on numerical simulations but also include some dedicated experimental studies.

The neuropsychiatric phenotype in CACNA1A mutations: a retrospective single center study and review of the literature

BACKGROUND AND PURPOSE

CACNA1A encodes the α1 subunit of the neuronal calcium channel P/Q. CACNA1A mutations underlie three allelic disorders: familial hemiplegic migraine type 1 (FHM1), episodic ataxia type 2 (EA2) and spinocerebellar ataxia type 6 (SCA6). A clear-cut genotype-phenotype correlation is often lacking since clinical manifestations may overlap. Several case reports have described cognitive and behavioral features in CACNA1A disorders, but studies in larger case series are lacking.

METHODS

Genetically confirmed CACNA1A cases were retrieved from the database of the ataxia outpatient clinic of the Department of Neurology at Innsbruck Medical University. Clinical charts and neuropsychological test results were retrospectively analyzed. In addition, a review of the literature including only genetically confirmed cases was performed.

RESULTS

Forty-four CACNA1A cases were identified in our database. Delayed psychomotor milestones and poor school performance were described in seven (four FHM1, three EA2) and eight (three FHM1, five EA2) patients, respectively. Psychiatric comorbidities were diagnosed in eight patients (two FHM1, six EA2). Neuropsychological testing was available for 23 patients (11 FHM1, 10 EA2, two SCA6). Various cognitive deficits were documented in 21 cases (all patients except one SCA6). Impairments were predominantly seen in figural memory, visuoconstructive abilities and verbal fluency. In the literature, an early psychomotor delay is described in several children with EA2 and FHM1, whilst reports of cognitive and psychiatric findings from adult cases are scarce.

CONCLUSIONS

Neuropsychiatric manifestations are common in episodic CACNA1A disorders. In the case of otherwise unexplained developmental delay and a positive family history, CACNA1A mutations should be considered in the differential diagnosis.

Improving aeration systems in saline water: measurement of local bubble size and volumetric mass transfer coefficient of conventional membrane diffusers

In this study, for the first time, the influence of the design of conventional membrane diffusers on the volumetric mass transfer coefficient (k_La) and bubble size in tap water (TW) and saline water (SW) was investigated (up to 15 g/L NaCl). By using a new analytical approach, k_La and the bubble size along the ascent of the bubble swarm were measured simultaneously and in real time. The results show that in TW, after collision bubbles merge into larger bubbles by coalescence. In SW, coalescence is inhibited by salt. Due to the smaller bubble size, k_La increases to more than double compared to TW. The results show that in SW, membrane diffusers with dense slit patterns and smaller slit lengths are to be recommended in order to enable improved utilization of oxygen in saline water.

[Rebiopsy for Patients with Lung Cancer - Joint Opinion from both the Endoscopic and Thoracic Oncology Sections of the German Society of Pneumology (DGP)]

Performing rebiopsies for primary lung cancer and/or their metastases is becoming more and more prominent in daily practice, as the therapeutical spectrum increases and some newer strategies are dependent on immunohistochemical and/or molecular factors. In general, nearly all recurrent lesions or metastases can be reached. However, frequently invasive procedures are necessary with the need to carefully weigh risks and benefits of rebiopsies for the patient in each case. In this review indications for recurrent and progressive disease as well as risks are discussed and alternatives to rebiopsies are shown. This work is the joint opinion from both the endoscopic and thoracic oncology sections of the German Society of Pneumology (DGP).

Changes in Plasminogen Activator Activity and Plasmin Inhibition in the Pig During Experimental Hypovolaemia

A markedly decreased plasminogen activator activity (PAA) was seen in lung, heart and kidney after experimental hypovolemia in the pig. In 2 of 12 cases, an increased PAA was found in liver and spleen. In skeletal muscle, skin, sciatic nerve and in 10 of 12 cases in liver and spleen PAA was unchanged. A slightly increased plasmin inhibition was noted only in the lung. These changes in tissue PAA were reflected by an increase in the PAA of euglobulin fractions concomitant with a decrease in antiplasmin activity in the blood samples obtained during the bleeding experiments.

Characterisation of a major phytoplankton bloom in the River Thames (UK) using flow cytometry and high performance liquid chromatography

Recent river studies have observed rapid phytoplankton dynamics, driven by diurnal cycling and short-term responses to storm events, highlighting the need to adopt new high-frequency characterisation methods to understand these complex ecological systems. This study utilised two such analytical methods; pigment analysis by high performance liquid chromatography (HPLC) and cell counting by flow cytometry (FCM), alongside traditional chlorophyll spectrophotometry and light microscopy screening, to characterise the major phytoplankton bloom of 2015 in the River Thames, UK. All analytical techniques observed a rapid increase in chlorophyll a concentration and cell abundances from March to early June, caused primarily by a diatom bloom. Light microscopy identified a shift from pennate to centric diatoms during this period. The initial diatom bloom coincided with increased HPLC peridinin concentrations, indicating the presence of dinoflagellates which were likely to be consuming the diatom population. The diatom bloom declined rapidly in early June, coinciding with a storm event. There were low chlorophyll a concentrations (by both HPLC and spectrophotometric methods) throughout July and August, implying low biomass and phytoplankton activity. However, FCM revealed high abundances of pico-chlorophytes and cyanobacteria through July and August, showing that phytoplankton communities remain active and abundant throughout the summer period. In combination, these techniques are able to simultaneously characterise a wider range of phytoplankton groups, with greater certainty, and provide improved understanding of phytoplankton functioning (e.g. production of UV inhibiting pigments by cyanobacteria in response to high light levels) and ecological status (through examination of pigment degradation products). Combined HPLC and FCM analyses offer rapid and cost-effective characterisation of phytoplankton communities at appropriate timescales. This will allow a more-targeted use of light microscopy to capture phytoplankton peaks or to investigate periods of rapid community succession. This will lead to greater system understanding of phytoplankton succession in response to biogeochemical drivers.

Extent of Microstructural Tissue Damage Correlates with Hemodynamic Failure in High-Grade Carotid Occlusive Disease: An MRI Study Using Quantitative T2 and DSC Perfusion

BACKGROUND AND PURPOSE

Chronic hemodynamic impairment in high-grade carotid occlusive disease is thought to cause microstructural abnormalities that might be subclinical or lead to subtle symptoms including cognitive impairment. Quantitative MR imaging allows assessing pathologic structural changes beyond macroscopically visible tissue damage. In this study, high-resolution quantitative T2 mapping combined with DSC-based PWI was used to investigate quantitative T2 changes as a potential marker of microstructural damage in relation to hemodynamic impairment in patients with unilateral high-grade carotid occlusive disease.

MATERIALS AND METHODS

Eighteen patients with unilateral high-grade ICA or MCA stenosis/occlusion were included in the study. T2 values and deconvolved perfusion parameters, including relative CBF, relative CBV, and the relative CBF/relative CBV ratio as a potential indicator of local cerebral perfusion pressure, were determined within areas with delayed TTP and compared with values from contralateral unaffected areas after segmentation of normal-appearing hypoperfused WM and cortical regions. Hemispheric asymmetry indices were calculated for all parameters.

RESULTS

Quantitative T2 was significantly prolonged (P < .01) in hypoperfused tissue and correlated significantly (P < .01) with TTP delay and relative CBF/relative CBV reduction in WM. Significant correlations (P < .001) between TTP delay and the relative CBF/relative CBV ratio were found both in WM and in cortical areas.

CONCLUSIONS

Quantitative T2 can be used as a marker of microstructural tissue damage even in normal-appearing GM and WM within a vascular territory affected by high-grade carotid occlusive disease. Furthermore, the extent of damage correlates with the degree of hemodynamic failure measured by DSC perfusion parameters.

[Informal care for dementia according to type of service]

BACKGROUND

Dementia is a major challenge for society and its impact will grow in the future. Informal care is an essential part of dementia care. Previous studies considered informal care as a whole and not by its components.

OBJECTIVE

We aimed to assess the degree of association between specific informal care services and dementia.

MATERIAL AND METHODS

This analysis is based on data from the seventh wave of the AgeCoDe/AgeQualiDe study. Dementia was diagnosed based on the DSM-IV criteria. Severity of dementia was assessed and categorized by means of the Clinical Dementia Rating and eight individual informal care services were considered. Logistic regression models were used to assess associations.

RESULTS

Of the 864 participants 18% suffered from dementia (very mild: 4%; mild: 6%; moderate: 5%; severe: 3%). All informal care services were significantly associated with dementia, with an emphasis on "supervision", "regulation of financial matters" and "assistance in the intake of medication". Considering different degrees of dementia severity, similar results arose from the analyses. All three aforementioned services showed a pronounced association with all degrees of dementia severity, except for supervision and very mild dementia.

CONCLUSION

The provision of all types of informal care services is associated with dementia. The association is pronounced for services that can be more easily integrated into the daily routines of the informal caregiver. Policy makers who plan to integrate informal care into the general care arrangements for dementia should consider this.

Long-term survival of kidney grafts in lupus nephritis: a Mexican cohort

Kidney transplant for patients with lupus nephritis (LN) has satisfactory outcomes in studies with short-term or mid-term follow up. Nevertheless, information about long-term outcomes is scarce. We performed a retrospective matched-pair cohort study in 74 LN recipients compared with 148 non-LN controls matched by age, sex, immunosuppressive treatment, human leukocyte antigen (HLA) matches, and transplant period in order to evaluate long-term outcomes of kidney transplant in LN recipients. Matched pairs were predominantly females (83%), median age at transplant surgery of 32 years (interquartile range 23–38 years), and 66% received a graft from a living related donor. Among LN recipients, 5-, 10-, 15-, and 20-year graft survival was 81%, 79%, 57% and 51%, respectively, and it was similar to that observed in controls (89%, 78%, 64%, and 56%, respectively). Graft loss (27% vs. 21%, p = 0.24) and overall survival ( p = 0.15) were not different between LN recipients and controls. Also, there was no difference in episodes of immunological rejection, thrombosis, or infection. Only six LN recipients had biopsy-proven lupus recurrence and three of them had graft loss. In a cohort with a long follow up of kidney transplant recipients, LN recipients had similar long-term graft survival and overall outcomes compared with non-lupus recipients when predictors are matched between groups.

Biomechanical in vitro comparison of suture anchors for thumb UCL repair

Different types of intraosseous suture anchors can be used for thumb ulnar collateral ligament (UCL) repair surgery. Some of them have already been tested biomechanically in intact bone; however, there exists little knowledge of their stability when implanted in avulsion fracture. In this biomechanical in vitro study, three anchor types (hard, soft and novel BoneWelding) were tested on 24 fresh frozen human thumbs from 12 body donors. After the repair of an iatrogenic ligamentous UCL rupture, the thumbs were cyclically loaded. A new set of anchors was implanted at the contralateral radial side of the same specimen into an iatrogenic avulsion fracture and pulled out of the bone. The most common mode of failure in ligamentous UCL repairs was the suture-ligament interface, especially when using soft anchors. In avulsion fractures, the novel anchor withstood significantly higher pullout forces than the hard or soft anchor (65 N vs. 42 N vs. 27 N; p = .006). The BW anchor provides sufficient anchorage in trabecular bone for UCL repair in case of avulsion fractures.

[Laparoscopic versus open rectal cancer resection: oncologically equal?]

The oncological equivalence of laparoscopic and open rectal cancer resection was evaluated in four multicenter randomized controlled trials. The COLOR II and the COREAN trials demonstrated oncological equivalence; however, the ACOSOG and the ALaCaRT studies came to a different conclusion. In the latter two studies a composite endpoint that assessed the quality of the mesorectal specimen, the completeness of tumor-free circumferential and distal resection margins was chosen. In both trials a higher success rate for open surgery was shown; nevertheless, the validity of this composite endpoint has not been proven and no conclusions on solid oncological endpoints can be drawn. The COLOR II and the COREAN trial therefore remain the only available studies which investigated solid oncological endpoints, such as local recurrence and disease-free survival over an adequate follow-up time period of 3 years; however, the comparability of the study groups at least of the COLOR II trial needs to be called into question as only the experience of the laparoscopic surgeons was assessed. With a local recurrence rate of 5 % in both groups the oncological quality seems nevertheless to be good; therefore, a systematically inadequate control group should not be assumed. At this point it can be concluded that a good oncological outcome can be achieved with laparoscopic rectal resection in the hands of experts. For a final assessment the long-term results of the on-going trials needs to be awaited. If the promising results for laparoscopic surgery of the COLOR II trial are confirmed laparoscopic rectal resection should be preferred to open resection in the future. This conclusion is based on the generally known perioperative benefits of minimally invasive surgery.