Suction-induced habitat selection in sand bubbler crabs.
ABSTRACT: We show that a decapod crustacean, the sand bubbler crab (SBC) Scopimera globosa, uses suction, which is the tension of moisture in the sediment, to select habitats at normal times and at the time of disaster events, through a range of controlled laboratory experiments and field observations at various sandflats in Japan. When SBCs are released on fields with no spatial suction gradient, their direction of movement is random. However, the situation clearly changes with increasing suction gradients, in which case the SBCs move to suitable zones for burrowing. Predictions based on suction-burrowing relationships coupled with the knowledge of geophysical state changes induced by suction dynamics are consistent with the observed formation of habitats throughout the seasons. Such suction-induced habitat selection in SBCs manifests itself in a robust way even following sudden events such as typhoons, where erosion and deposition processes distinctly alter the geomorphological profiles, as well as the states of suction, yet consistently yielding habitats at the newly formed, suitable suction environments. Repeated battles were observed in a suitable suction environment over burrows, with the competition rate more than seven times as high as that in a critical suction environment for burrowing.
Project description:We examined the clinical/pathologic features of ipsilateral second breast cancers (IP-SBCs) following breast-conserving surgery (BCS) for DCIS among community-treated patients and ascertained the degree of correlation between the features of index DCIS and IP-SBC events. From a Cancer Research Network cohort of DCIS patients diagnosed 1990-2001 and treated with BCS, we identified women who subsequently developed an ipsilateral DCIS or invasive breast cancer. All index DCIS tumors underwent expert pathology review. Pathologic characteristics of IP-SBCs were abstracted from available medical records. Logistic regression was used to examine associations between pathologic characteristics and identify factors associated with invasive versus non-invasive IP-SBC. Of 1969 DCIS patients, 182 developed an IP-SBC within a median of 38 months (range 6-160). IP-SBCs were slightly more commonly non-invasive (53 %) versus invasive (47 %). Of invasive IP-SBCs, 31 % were high grade, 67 % were <20 mm, 74 % were estrogen receptor positive, 7 % were HER2 positive, and 16 % were node positive. Of non-invasive IP-SBCs, 33 % were high grade. Comparing index DCIS and IP-SBC specimens, there was moderate-high correlation for HR status and grade. Among patients with IP-SBCs, those who were younger and whose index DCIS tumors were HR negative had shorter intervals (within 3 years) between index and IP-SBC diagnoses. No index DCIS feature was statistically significantly associated with an IP-SBC that was invasive versus non-invasive. Understanding the characteristics of SBCs and identifying correlations between these and index DCIS events could influence treatment choices for DCIS, and may help patients and providers develop treatment paradigms for SBCs.
Project description:The spatial boundary condition (SBC) arising from the surrounding microenvironment imposes specific geometry and spatial constraints that affect organogenesis and tissue homeostasis. Mesenchymal stromal cells (MSCs) sensitively respond to alterations of mechanical cues generated from the SBC. However, mechanical cues provided by a three-dimensional (3D) environment are deprived in a reductionist 2D culture system. This study investigates how SBC affects osteogenic differentiation of MSCs using 3D scaffolds with monodispersed pores and homogenous spherical geometries. MSCs cultured under SBCs with diameters of 100 and 150??m possessed the greatest capability of osteogenic differentiation. This phenomenon was strongly correlated with MSC morphology, organization of actin cytoskeleton, and distribution of focal adhesion involving ?2 and ?5 integrins. Further silencing either ?2 or ?5 integrin significantly reduced the above mentioned mechanosensitivity, indicating that the ?2 and ?5 integrins as mechano-sensitive molecules mediate MSCs' ability to provide enhanced osteogenic differentiation in response to different spherical SBCs. Taken together, the findings provide new insights regarding how MSCs respond to mechanical cues from the surrounding microenvironment in a spherical SBC, and such biophysical stimuli should be taken into consideration in tissue engineering and regenerative medicine in conjunction with biochemical cues.
Project description:In this study, we aim to develop a narrow-diameter and long-bore device for minimally invasive surgery that achieves the simultaneous cutting and suction of body tissue such as the diseased part of an organ. In this paper, we propose a screw made of a thin metal plate, and we developed a prototype device using this screw. For smooth operation, the suction performance must be superior to the cutting performance. Therefore, we performed experiments and evaluated the suction performance of the developed device assuming the crushed tissue pieces correspond to a highly viscous fluid. From the results, we confirmed that the suction volume is almost proportional to the rotation speed of the screw in the low speed range, and the device has an upper limit of suction volume at a certain rotation speed. Considering practical use, its proportional speed range is suitable for the device controllability of cutting and suction volume, and the size of the device tip needs to be 1 mm or more. Based on these conditions, we are planning to examine the shape of the cutting edge for realizing efficient cutting and suction and we will complete the device.
Project description:Purpose: Celiac disease (CD) is a risk factor for developing Small Bowel Carcinoma (SBC) with a 14 folds higher risk than that of the general population. As SBCs associated with CD (CD-SBCs) are extremely rare, very few molecular data are currently available about their pathogenesis and information about CD-SBC transcriptomic profiling is completely lacking. Patients and Methods: We generated RNA-seq data on 13 CD-SBCs selected from the largest and well-characterized series of CD-SBCs published so far that was collected by the Small Bowel Cancer Italian Consortium. In all cases we compared the CD-SBC transcriptional signatures with the four consensus molecular subtypes (CMS) of colorectal carcinoma (CRC) applying the ‘CMS classifier’. CpG Island Methylator Phenotype (CIMP+) was evaluated in all cases using methylation-sensitive multiple ligation-dependent probe amplification. Results: RNA-based signatures of CD-SBCs exhibited strong similarities with CRCs. Twelve of 13 CD-SBCs (92%) fell within the two main subtypes exhibiting high immune and inflammatory signatures, i.e. CMS1 and CMS4. CMS1 CD-SBCs (62% of cases) were commonly MSI/CIMP+ tumors and showed increased expression of genes associated with a diffuse TH1 and cytotoxic T immune infiltrate, up-regulation of apoptosis, cell cycle progression and proteasome pathways. CMS4 CD-SBCs (31% of cases) showed prominent TGF-β activation and were characterized by complement-associated inflammation, matrix remodeling, stromal invasion and angiogenesis Conclusions: RNA-based signatures of CD-SBCs strongly recapitulate CMS classification of CRC, give a promising tool to improve our knowledge of this rare entity and provide clinically useful information using the wealth of data available for CRC.
Project description:Interneurons play a key role in cortical function and dysfunction, yet organization of cortical interneuronal circuitry remains poorly understood. Cortical Layer 1 (L1) contains 2 general GABAergic interneuron groups, namely single bouquet cells (SBCs) and elongated neurogliaform cells (ENGCs). SBCs predominantly make unidirectional inhibitory connections (SBC?) with L2/3 interneurons, whereas ENGCs frequently form reciprocal inhibitory and electric connections (ENGC?) with L2/3 interneurons. Here, we describe a systematic investigation of the pyramidal neuron targets of L1 neuron-led interneuronal circuits in the rat barrel cortex with simultaneous octuple whole-cell recordings and report a simple organizational scheme of the interneuronal circuits. Both SBCs? and ENGC ? L2/3 interneuronal circuits connect to L2/3 and L5, but not L6, pyramidal neurons. SBC ? L2/3 interneuronal circuits primarily inhibit the entire dendritic-somato-axonal axis of a few L2/3 and L5 pyramidal neurons located within the same column. In contrast, ENGC ? L2/3 interneuronal circuits generally inhibit the distal apical dendrite of many L2/3 and L5 pyramidal neurons across multiple columns. Finally, L1 interneuron-led circuits target distinct subcellular compartments of L2/3 and L5 pyramidal neurons in a L2/3 interneuron type-dependent manner. These results suggest that L1 neurons form canonical interneuronal circuits to control information processes in both supra- and infragranular cortical layers.
Project description:OBJECTIVE: There is increasing interest in patients with metachronous (MBC) and synchronous breast cancer (SBC). The objective of this study was to evaluate the occurrence and outcome of MBCs and SBCs. METHODS: A retrospective study on women operated in our department for breast cancer between 2002 and 2005 was carried out. Patients were divided into three groups: women with MBC, SBC, and unilateral breast cancer (UBC). Moreover, we performed a meta-analysis of the English literature about multiple breast cancers between 2000 and 2011 taking into consideration their prevalence and overall survival (OS). RESULTS: We identified 584 breast cancer patients: 16 women (3%) presented SBC and 40 MBC (7%, second cancer after 72-month follow-up IQR 40-145). Although the meta-analysis showed significant OS differences between MBC or SBC and UBC, we did not observe any significant OS difference among the three groups of our population. Anyway, we found a significant worse disease-free survival in MBC than UBC and a significant higher prevalence of radical surgery in MBC and SBC than UBC. CONCLUSIONS: Despite the low prevalence of MBC and SBC, the presence of a long time risk of MBC confirms the crucial role of ipsi- and contralateral mammographies in the postoperative follow-up.
Project description:Neuronal inhibition is crucial for temporally precise and reproducible signaling in the auditory brainstem. Previously we showed that for various synthetic stimuli, spherical bushy cell (SBC) activity in the Mongolian gerbil is rendered sparser and more reliable by subtractive inhibition (Keine et al., 2016). Here, employing environmental stimuli, we demonstrate that the inhibitory gain control becomes even more effective, keeping stimulated response rates equal to spontaneous ones. However, what are the costs of this modulation? We performed dynamic stimulus reconstructions based on neural population responses for auditory nerve (ANF) input and SBC output to assess the influence of inhibition on acoustic signal representation. Compared to ANFs, reconstructions of natural stimuli based on SBC responses were temporally more precise, but the match between acoustic and represented signal decreased. Hence, for natural sounds, inhibition at SBCs plays an even stronger role in achieving sparse and reproducible neuronal activity, while compromising general signal representation.
Project description:Background Development of the flexible CO2 fiber has presented new opportunities for the use of precision laser cutting in cranial procedures. The efficacy of the CO2 scalpel is further enhanced by combining it with a fluid removal suction capability. Objectives We report our experience with a novel CO2 laser-suction device. Methods The novel laser-suction device was designed in conjunction with OmniGuide Inc. (Cambridge, Massachusetts, USA). We performed a case review of its use in firm tumors that were resistant to resection by bipolar, suction, and ultrasonic aspirator. Results The laser-suction device was applied in three tumors where resection with ultrasonic aspiration failed. Tumor resection using the laser-suction device was successful in all three cases. There were no complications related to the laser-suction device. There were no instances of intraoperative device malfunction. Discussion The CO2 laser combined with suction is a useful instrument for resection of firm tumors that prove to be resistant to ultrasonic aspiration. We also find it to be useful in settings where precise tissue incisions are desired with minimal manipulation. In our experience, the surgical efficiency of the CO2 laser is improved by the laser-suction device. This device allows the surgeon to utilize a suction device and laser in a single hand and enables concurrent use of bipolar electrocautery without repeated instrument changes.
Project description:Ongoing anatomical development typically results in a gradual maturation of the feeding movements from larval to adult fishes. Adult seahorses are known to capture prey by rotating their long-snouted head extremely quickly towards prey, followed by powerful suction. This type of suction is powered by elastic recoil and requires very precise coordination of the movements of the associated feeding structures, making it an all-or-none phenomenon. Here, we show that newborn Hippocampus reidi are able to successfully feed using an extremely rapid and powerful snout rotation combined with a high-volume suction, surpassing that observed in adult seahorses. An inverse dynamic analysis shows that an elastic recoil mechanism is also used to power head rotation in newborn H. reidi. This illustrates how extreme levels of performance in highly complex musculoskeletal systems can be present at birth given a delayed birth and rapid development of functionally important structures. The fact that the head skeleton of newborn seahorses is still largely cartilaginous may not be problematic because the hydrodynamic stress on the rotating snout appeared considerably lower than in adult syngnathids.
Project description:It has been shown experimentally that cratered surfaces may have better adhesion properties than flat ones. However, the suction effect produced by the craters, which may be chiefly responsible for the improved adhesion, has not been properly modelled. This paper combines experimental, numerical simulation and analytical approaches towards developing a framework for quantifying the suction effect produced by isolated craters and cratered surfaces. The modelling approach emphasizes the essential role of large elastic deformation, while the airflow dynamics, microscopic mechanisms, like surface tension and air permeation, and rate-dependence are neglected. This approach is validated using experimental data for isolated hemi-spherical craters. The modelling approach is further applied to spherical cap (not necessarily hemi-spherical) craters with the objective of identifying optimal geometric and material properties, as well as the minimum preload necessary for attaining the maximum suction force. It is determined that stiff polymers with deep craters are capable of producing large suction forces. For soft materials, central to biomedical applications, large suction forces can be attained by reinforcing deep craters with thin stiff layers. Parametric optimization studies of reinforced craters reveal that some of them perform beyond common expectations. However, those high-performance reinforced craters are prone to surface instabilities, and therefore the practical use of such craters may be problematic.