Oscillatory Neural Network-Based Ising Machine Using 2D Memristors

Neural networks are increasingly used to solve optimization problems in various fields, including operations research, design automation, and gene sequencing. However, these networks face challenges due to the nondeterministic polynomial time (NP)-hard issue, which results in exponentially increasing computational complexity as the problem size grows. Conventional digital hardware struggles with the von Neumann bottleneck, the slowdown of Moore's law, and the complexity arising from heterogeneous system design. Two-dimensional (2D) memristors offer a potential solution to these hardware challenges, with their in-memory computing, decent scalability, and rich dynamic behaviors. In this study, we explore the use of nonvolatile 2D memristors to emulate synapses in a discrete-time Hopfield neural network, enabling the network to solve continuous optimization problems, like finding the minimum value of a quadratic polynomial, and tackle combinatorial optimization problems like Max-Cut. Additionally, we coupled volatile memristor-based oscillators with nonvolatile memristor synapses to create an oscillatory neural network-based Ising machine, a continuous-time analog dynamic system capable of solving combinatorial optimization problems including Max-Cut and map coloring through phase synchronization. Our findings demonstrate that 2D memristors have the potential to significantly enhance the efficiency, compactness, and homogeneity of integrated Ising machines, which is useful for future advances in neural networks for optimization problems.

Orbital Gating Driven by Giant Stark Effect in Tunneling Phototransistors

Conventional gating in transistors uses electric fields through external dielectrics that require complex fabrication processes. Various optoelectronic devices deploy photogating by electric fields from trapped charges in neighbor nanoparticles or dielectrics under light illumination. Orbital gating driven by giant Stark effect is demonstrated in tunneling phototransistors based on 2H-MoTe₂ without using external gating bias or slow charge trapping dynamics in photogating. The original self-gating by light illumination modulates the interlayer potential gradient by switching on and off the giant Stark effect where the d_z 2-orbitals of molybdenum atoms play the dominant role. The orbital gating shifts the electronic bands of the top atomic layer of the MoTe₂ by up to 100 meV, which is equivalent to modulation of a carrier density of 7.3 × 10¹¹ cm^-2 by electrical gating. Suppressing conventional photoconductivity, the orbital gating in tunneling phototransistors achieves low dark current, practical photoresponsivity (3357 AW^-1 ), and fast switching time (0.5 ms) simultaneously.

Collaborative health systems ECHO: The use of a tele-education platform to facilitate communication and collaboration with recipients of state targeted response funds in Pennsylvania

Background: The opioid epidemic continues to erode communities across Pennsylvania (PA). Federal and PA state programs developed grants to establish Hub and Spoke programs for the expansion of medications for opioid use disorders (MOUD). Employing the telementoring platform Project ECHO (Extension for Community Health Outcomes), Penn State Health engaged the other seven grant awardees in a Collaborative Health Systems (CHS) ECHO. We conducted key informant interviews to better understand impact of the CHS ECHO on health systems collaboration and opioid crisis efforts. Methods: For eight one-hour sessions, each awardee presented their unique strategies, challenges, and opportunities. Using REDCap, program characteristics, such as number of waivered prescribers and number of patients served were collected at baseline. After completion of the sessions, key informant interviews were conducted to assess the impact of CHS ECHO on awardee's programs. Results: Analysis of key informant interviews revealed important themes to address opioid crisis efforts, including the need for strategic and proactive program reevaluation and the convenience of collaborative peer learning networks. Participants expressed benefits of the CHS ECHO including allowing space for discussion of challenges and best practices and facilitating conversation on collaborative targeted advocacy and systems-level improvements. Participants further reported bolstered motivation and confidence. Conclusions: Utilizing Project ECHO provided a bidirectional platform of learning and support that created important connections between institutions working to combat the opioid epidemic. CHS ECHO was a unique opportunity for productive and convenient peer learning across external partners. Open dialogue developed during CHS ECHO can continue to direct systems-levels improvements that benefit individual and population outcomes.

Cross-Kingdom Cell-to-Cell Interactions in Cariogenic Biofilm Initiation

Candida albicans is known to form polymicrobial biofilms with various Streptococcus spp., including mitis and mutans group streptococci. Streptococcus gordonii (mitis group) has been shown to bind avidly to C. albicans hyphae via direct cell-to-cell interaction, while the cariogenic pathogen Streptococcus mutans (mutans group) interacts with the fungal cells via extracellular glucans. However, the biophysical properties of these cross-kingdom interactions at the single-cell level during the early stage of biofilm formation remain understudied. Here, we examined the binding forces between S. mutans (or S. gordonii) and C. albicans in the presence and absence of in situ glucans on the fungal surface using single-cell atomic force microscopy and their influence on biofilm initiation and subsequent development under cariogenic conditions. The data show that S. gordonii binding force to the C. albicans surface is significantly higher than that ofS. mutans to the fungal surface (~2-fold). However, S. mutans binding forces are dramatically enhanced when the C. albicans cell surface is locally coated with extracellular glucans (~6-fold vs. uncoated C. albicans), which vastly exceeds the forces between S. gordonii andC. albicans. The enhanced binding affinity of S. mutans to glucan-coated C. albicans resulted in a larger structure during early biofilm initiation compared to S. gordonii-C. albicans biofilms. Ultimately, this resulted in S. mutans dominance composition in the 3-species biofilm model under cariogenic conditions. This study provides a novel biophysical aspect of Candida-streptococcal interaction whereby extracellular glucans may selectively favor S. mutans binding interactions with C. albicans during cariogenic biofilm development.

3D micro fractal pipettes for capillary based robotic liquid handling

Miniaturized and mobile liquid handling devices are essential elements to biological or clinical applications. This will innovate the conventional liquid handling methods such as manual or automated pipetting systems. Here, we propose the micro fractal pipette as the candidate device for this objective. It is made of epoxy polymer and printed by innovative 3D nanoprinting technology based on two-photon absorption polymerization with sub-micrometer resolution. We demonstrated the efficient liquid handling performance by using the micro fractal pipette between the source droplet and the target hydrogel substrate. This is due to the high porosity (78%) and the 8.5 times larger cavity surface area compared to the full pyramid. The biomimetic inner cavity microchannel networks contribute to the low pressure drop. The proposed micro fractal pipette could also innovate the versatile and miniaturized liquid handling system, promising to various biological or clinical applications.

The Healthy Champions program in Pennsylvania schools: Assessment, awareness, and improvement of school wellness

Schools are important environments for promotion of healthy behaviors to reduce childhood obesity; however, many barriers prevent schools from sustaining wellness programs. The goal of the Healthy Champions program was to assist schools with identifying areas for improvement through a nutrition and activity-focused assessment, and delivery of a customized score report and welcome kit with materials to promote healthful behavior change. In this study, we aimed to describe participation and assessment results for this program across a five-year period. Enrollment in the Healthy Champions program was open to private and public K-12 schools across Pennsylvania beginning in 2013. School staff completed an assessment that scored aspects of the wellness environment and was used to enroll schools in the program. Schools were awarded star status (0–5) based upon responses and provided a tailored response to improve ratings, and with re-enrollment, became a simple way for schools to track progress. From 2013 to 2018, 592 schools enrolled for at least one year, representing 58 out of 67 counties (87%) in Pennsylvania. Mean star status at baseline was 2.89 out of 5; however, schools enrolled for multiple years (51%) saw significant improvement in star status, independent of school size and rural/urban status.

Convergence in disability policies in the welfare states Denmark, Sweden, the UK and Australia?

Background

A state’s relation to citizens who are not able to support themselves due to illness is one of the cornerstones of welfare states. However, rising numbers of people on disability benefits is a challenge in many welfare states. The first aim is to investigate how policies around eligibility to disability benefits articulate a concept of ’incapacity to work’ across social democratic (Denmark and Sweden) and liberal welfare states (Australia and the UK). Secondly, we wish to explore how the conceptualisation of capacity and incapacity to work shapes prevailing constructions of disability.

Methods

In this study, we analyse official policy documents from governments, legislation, scientific and grey literature on disability benefit reforms in the selected countries. The analytical framework introduces the notion of decommodification of labour for people with disability and the ’social model of disability’ in relation to the constructions of disability in current disability benefit reforms.

Results (preliminary)

Restricting access to disability benefits has been a key feature of the recent reforms across all different types of welfare states. Liberal welfare states are more pervasive in reassessment of previously granted benefits compared to social democratic welfare states. The construction of disability in recent reforms is at odds with the social model of disability.

Conclusions (preliminary)

Across both liberal and social democratic welfare states eligibility for disability benefits is articulated around notions of incapacity to work. Retrenchment of benefits is, overall, most pervasive in liberal welfare states.

Key messages

The convergence in social policies across both social democratic and liberal welfare states speaks to the pervasiveness of neo-liberal notions in current social policy. The tightening of eligibility criteria for disability benefits poses great financial and health risks to people with illness struggling to support themselves.

Dual-Targeting Approach Degrades Biofilm Matrix and Enhances Bacterial Killing

Biofilm formation is a key virulence factor responsible for a wide range of infectious diseases, including dental caries. Cariogenic biofilms are structured microbial communities embedded in an extracellular matrix that affords bacterial adhesion-cohesion and drug tolerance, making them difficult to treat using conventional antimicrobial monotherapy. Here, we investigated a multitargeted approach combining exopolysaccharide (EPS) matrix-degrading glucanohydrolases with a clinically used essential oils-based antimicrobial to potentiate antibiofilm efficacy. Our data showed that dextranase and mutanase can synergistically break down the EPS glucan matrix in preformed cariogenic biofilms, markedly enhancing bacterial killing by the antimicrobial agent (3-log increase versus antimicrobial alone). Further analyses revealed that an EPS-degrading/antimicrobial (EDA) approach disassembles the matrix scaffold, exposing the bacterial cells for efficient killing while concurrently causing cellular dispersion and "physical collapse" of the bacterial clusters. Unexpectedly, we found that the EDA approach can also selectively target the EPS-producing cariogenic bacteria Streptococcus mutans with higher killing specificity (versus other species) within mixed biofilms, disrupting their accumulation and promoting dominance of commensal bacteria. Together, these results demonstrate a dual-targeting approach that can enhance antibiofilm efficacy and precision by dismantling the EPS matrix and its protective microenvironment, amplifying the killing of pathogenic bacteria within.

Therapeutic Strategies Targeting Cariogenic Biofilm Microenvironment

Cariogenic biofilms are highly structured microbial communities embedded in an extracellular matrix, a multifunctional scaffold that is essential for the existence of the biofilm lifestyle and full expression of virulence. The extracellular matrix provides the physical and biological properties that enhance biofilm adhesion and cohesion, as well as create a diffusion-modulating milieu, protecting the resident microbes and facilitating the formation of localized acidic pH niches. These biochemical properties pose significant challenges for the development of effective antibiofilm therapeutics to control dental caries. Conventional approaches focusing solely on antimicrobial activity or enhancing remineralization may not achieve maximal efficacy within the complex biofilm microenvironment. Recent approaches disrupting the biofilm microbial community and the microenvironment have emerged, including specific targeting of cariogenic pathogens, modulation of biofilm pH, and synergistic combination of bacterial killing and matrix degradation. Furthermore, new "smart" nanotechnologies that trigger drug release or activation in response to acidic pH are being developed that could enhance the efficacy of current and prospective chemical modalities. Therapeutic strategies that can locally disrupt the pathogenic niche by targeting the biofilm structure and its microenvironment to eliminate the embedded microorganism and facilitate the action of remineralizing agents may lead to enhanced and precise anticaries approaches.

Depletion of SMC5/6 sensitizes male germ cells to DNA damage

The structural maintenance of chromosomes complex SMC5/6 is thought to be essential for DNA repair and chromosome segregation during mitosis and meiosis. To determine the requirements of the SMC5/6 complex during mouse spermatogenesis we combined a conditional knockout allele for Smc5, with four germ cell–specific Cre-recombinase transgenes, Ddx4-Cre, Stra8-Cre, Spo11-Cre, and Hspa2-Cre, to mutate Smc5 in spermatogonia, in spermatocytes before meiotic entry, during early meiotic stages, and during midmeiotic stages, respectively. Conditional mutation of Smc5 resulted in destabilization of the SMC5/6 complex. Despite this, we observed only mild defects in spermatogenesis. Mutation of Smc5 mediated by Ddx4-Cre and Stra8-Cre resulted in partial loss of preleptotene spermatocytes; however, spermatogenesis progresses and mice are fertile. Mutation of Smc5 via Spo11-Cre or Hspa2-Cre did not result in detectable defects of spermatogenesis. Upon exposure to gamma irradiation or etoposide treatment, each conditional Smc5 mutant demonstrated an increase in the number of enlarged round spermatids with multiple acrosomes and supernumerary chromosome content. We propose that the SMC5/6 complex is not acutely required for premeiotic DNA replication and meiotic progression during mouse spermatogenesis; however, when germ cells are challenged by exogenous DNA damage, the SMC5/6 complex ensures genome integrity, and thus, fertility.

Synaptic Computation Enabled by Joule Heating of Single-Layered Semiconductors for Sound Localization

Synaptic computation, which is vital for information processing and decision making in neural networks, has remained technically challenging to be demonstrated without using numerous transistors and capacitors, though significant efforts have been made to emulate the biological synaptic transmission such as short-term and long-term plasticity and memory. Here, we report synaptic computation based on Joule heating and versatile doping induced metal-insulator transition in a scalable monolayer-molybdenum disulfide (MoS₂) device with a biologically comparable energy consumption (∼10 fJ). A circuit with our tunable excitatory and inhibitory synaptic devices demonstrates a key function for realizing the most precise temporal computation in the human brain, sound localization: detecting an interaural time difference by suppressing sound intensity- or frequency-dependent synaptic connectivity. This Letter opens a way to implement synaptic computing in neuromorphic applications, overcoming the limitation of scalability and power consumption in conventional CMOS-based neuromorphic devices.

Prophylactic Antiplatelet Medication in Endovascular Treatment of Intracranial Aneurysms: Low-Dose Prasugrel versus Clopidogrel

BACKGROUND AND PURPOSE

Prophylactic antiplatelet medication is beneficial in decreasing thromboembolic complications during endovascular treatment of unruptured intracranial aneurysms. The efficacy may be limited by variability of individual response to antiplatelet medication, especially clopidogrel. We compared the efficacy of 2 antiplatelet medications, low-dose prasugrel and clopidogrel, in patients undergoing endovascular treatment of unruptured aneurysms.

MATERIALS AND METHODS

From November 2014 to July 2015, 194 patients with a total of 222 unruptured aneurysms underwent endovascular treatment at a single institution. Laboratory and clinical data from the prospectively maintained registry were used in this study. Antiplatelet medication was given the day before endovascular treatment (prasugrel 20 mg or 30 mg or clopidogrel 300 mg). Response to the antiplatelet medication was measured by the VerifyNow system. Periprocedural adverse event rates between the 2 groups were compared.

RESULTS

There were no significant differences in the baseline characteristics of patients and aneurysms between the 2 groups. The P2Y12 reaction unit values were lower (clopidogrel group versus prasugrel group, 242.7 ± 69.8 vs 125.7 ± 79.4; P < .0001) and percentage inhibition values were higher (22.1% ± 19.7% vs 60.2 ± 24.7%; P < .0001) in the prasugrel group. There were no thromboembolic events, but there was 1 procedural bleed in each group, without any clinical consequences.

CONCLUSIONS

The prasugrel group showed more effective and consistent platelet inhibition. We may omit the antiplatelet response assay with the low-dose prasugrel premedication before the endovascular treatment of patients with unruptured aneurysms. Further study is required to determine whether there is benefit of this strategy regarding clinical outcome.

Note: On-chip multifunctional fluorescent-magnetic Janus helical microswimmers

Microswimmers integrated into microfluidic devices that are capable of self-illumination through fluorescence could revolutionize many aspects of technology, especially for biological applications. Few illumination and propulsion techniques of helical microswimmers inside microfluidic channels have been demonstrated. This paper presents the fabrication, detachment, and magnetic propulsions of multifunctional fluorescent-magnetic helical microswimmers integrated inside microfluidics. The fabrication process is based on two-photon laser lithography to pattern 3-D nanostructures from fluorescent photoresist coupled with conventional microfabrication techniques for magnetic thin film deposition by shadowing. After direct integration inside a microfluidic device, injected gas bubble allows gentle detachment of the integrated helical microswimmers whose magnetic propulsion can then be directly applied inside the microfluidic channel using external electromagnetic coil setup. With their small scale, fluorescence, excellent resistance to liquid/gas surface tension, and robust propulsion capability inside the microfluidic channel, the microswimmers can be used as high-resolution and large-range mobile micromanipulators inside microfluidic channels.

The burrowing behavior of the nematode Caenorhabditis elegans: a new assay for the study of neuromuscular disorders

The nematode Caenorhabditis elegans has been a powerful model system for the study of key muscle genes relevant to human neuromuscular function and disorders. The behavioral robustness of C. elegans, however, has hindered its use in the study of certain neuromuscular disorders because many worm models of human disease show only subtle phenotypes while crawling. By contrast, in their natural habitat, C. elegans likely spends much of the time burrowing through the soil matrix. We developed a burrowing assay to challenge motor output by placing worms in agar-filled pipettes of increasing densities. We find that burrowing involves distinct kinematics and turning strategies from crawling that vary with the properties of the substrate. We show that mutants mimicking Duchenne muscular dystrophy by lacking a functional ortholog of the dystrophin protein, DYS-1, crawl normally but are severely impaired in burrowing. Muscular degeneration in the dys-1 mutant is hastened and exacerbated by burrowing, while wild type shows no such damage. To test whether neuromuscular integrity might be compensated genetically in the dys-1 mutant, we performed a genetic screen and isolated several suppressor mutants with proficient burrowing in a dys-1 mutant background. Further study of burrowing in C. elegans will enhance the study of diseases affecting neuromuscular integrity, and will provide insights into the natural behavior of this and other nematodes.

Binding Force Dynamics of Streptococcus mutans-glucosyltransferase B to Candida albicans

Candida albicans cells are often detected with Streptococcus mutans in plaque biofilms from children affected with early childhood caries. The coadhesion between these 2 organisms appears to be largely mediated by the S. mutans-derived exoenzyme glucosyltransferase B (GtfB); GtfB readily binds to C. albicans cells in an active form, producing glucans locally that provide enhanced binding sites for S. mutans. However, knowledge is limited about the mechanisms by which the bacterial exoenzyme binds to and functions on the fungal surface to promote this unique cross-kingdom interaction. In this study, we use atomic force microscopy to understand the strength and binding dynamics modulating GtfB-C. albicans adhesive interactions in situ. Single-molecule force spectroscopy with GtfB-functionalized atomic force microscopy tips demonstrated that the enzyme binds with remarkable strength to the C. albicans cell surface (~2 nN) and showed a low dissociation rate, suggesting a highly stable bond. Strikingly, the binding strength of GtfB to the C. albicans surface was ~2.5-fold higher and the binding stability, ~20 times higher, as compared with the enzyme adhesion to S. mutans. Furthermore, adhesion force maps showed an intriguing pattern of GtfB binding. GtfB adhered heterogeneously on the surface of C. albicans, showing a higher frequency of adhesion failure but large sections of remarkably strong binding forces, suggesting the presence of GtfB binding domains unevenly distributed on the fungal surface. In contrast, GtfB bound uniformly across the S. mutans cell surface with less adhesion failure and a narrower range of binding forces (vs. the C. albicans surface). The data provide the first insights into the mechanisms underlying the adhesive and mechanical properties governing GtfB interactions with C. albicans. The strong and highly stable GtfB binding to C. albicans could explain, at least in part, why this bacterially derived exoenzyme effectively modulates this virulent cross-kingdom interaction.

Note: Resistance spot welding using a microgripper

Interest in thin-film nanostructures as building blocks for nanoelectronics and nanoelectromechanical systems (NEMS) is increasing. Resistance spot welding (RSW) on a nano or micro scale can play a significant role; similar to that of its macro counterpart for forming connections in device assembly processes. This Note presents a novel micron scale RSW technique using a microgripper as mobile spot welding electrodes to assemble ultra-thin film nanostructures. As an example, assembly of three-dimensional helical nanobelt (HNB) based device was successfully demonstrated using the proposed system. The spot-welding process was fully monitored by the built-in capacitive micro force sensor of the microgripper. Experiments show that RSW, using the microgripper, provides a stable electrical contact with sufficient mechanical strength for the construction of devices such as HNB based devices demonstrated here.

Note: helical nanobelt force sensors

We present the fabrication and characterization of helical nanobelt force sensors. These self-sensing force sensors are based on the giant piezoresistivity of helical nanobelts. The three-dimensional helical nanobelts are self-formed from 27 nm-thick n-type InGaAs/GaAs bilayers using rolled-up techniques, and assembled onto electrodes on a micropipette using nanorobotic manipulations. The helical nanobelt force sensors can be calibrated using a calibrated atomic force microscope cantilever system under scanning electron microscope. Thanks to their giant piezoresistance coefficient (515 × 10(-10) Pa(-1)), low stiffness (0.03125 N/m), large-displacement capability (~10 μm), and good fatigue resistance, they are well suited to function as stand-alone, compact (~20 μm without the plug-in support), light (~5 g including the plug-in support), versatile and large range (~μN) and high resolution (~nN) force sensors.

The characteristics and risk factors of headache development after the coil embolization of an unruptured aneurysm

BACKGROUND AND PURPOSE

Development of a headache after aneurysm coil embolization is not uncommon but has received little attention. The authors prospectively analyze the characteristics and risk factors of a headache after coiling in patients treated for an unruptured cerebral aneurysm.

MATERIALS AND METHODS

Ninety patients treated for an unruptured cerebral aneurysm over a period of 1 year, and without a headache history within a month before coiling, were enrolled in this study. All coilings were successfully performed without neurologic complications. After coiling, headache development and intensities were recorded.

RESULTS

Fifty (55.6%) patients experienced a headache (VAS score, 4.5 ± 2.02) at 7.9 (range, 0-72) hours, on average, after coiling, and all headaches resolved within an average of 73.0 (range, 3-312) hours. Univariate analysis showed that the following were significantly associated with the development of a headache: age ≤ 50 years (OR 4.636, 95% CI, 1.414-15.198), hypertension (OR 0.232, 95% CI, 0.095-0.571), a packing attenuation of >25% (OR 3.619, 95% CI, 1.428-9.174), and a previous headache history (OR 2.769, 95% CI, 1.120-6.849). However, binary logistic regression showed that only a packing attenuation of >25% (P = .013, adjusted OR 3.774, 95% CI, 1.320-10.790) and no history of hypertension (P = .019, adjusted OR 3.515, 95% CI, 1.233-10.021) were independently associated with the development of a headache.

CONCLUSIONS

A headache frequently developed after the coiling of unruptured aneurysms. However, headaches were relatively benign and resolved within several days. The present study shows that no hypertension history and a packing attenuation of >25% are risk factors of headache development.

Comparison of 2-year angiographic outcomes of stent- and nonstent-assisted coil embolization in unruptured aneurysms with an unfavorable configuration for coiling

BACKGROUND AND PURPOSE

Stents are known to have hemodynamic and biologic effects in addition to their mechanical scaffold effect. To determine whether stents affect long-term outcomes after coiling of unruptured aneurysms, we compared angiographic outcomes at 2 years postembolization for stent- and nonstent-assisted coiled unruptured aneurysms.

MATERIALS AND METHODS

Stent-assisted coiling was used in unruptured aneurysms unfavorable for simple coiling (neck size >4 mm and dome-to-neck ratio <1.5) in our practice. Therefore, 126 coiled unruptured aneurysms in total (40 [31.7%] stent group and 86 [68.3%] nonstent group) with these conditions were selected for this study. The nonstent group aneurysms were treated with multiple microcatheter technique (53 cases) or balloon-assisted technique (33 cases). Self-expandable stents were used for coiling in stent group aneurysms. No significant difference in aneurysmal characteristics (aneurysm type [sidewall/bifurcation], diameter, neck size, and dome-to-neck ratio) or angiographic outcome at embolization (packing attenuation, obliteration grade, and contrast filling) were observed between the 2 study groups.

RESULTS

At 2-year follow-up visits, rates of progressive occlusion (stent group, 17/40 [42.5%] versus nonstent group, 34/86 [39.5%]) and recanalization (7/40 [17.5%] versus 18/86 [21.0%]) did not show a statistically significant difference between the 2 groups (P = .895).

CONCLUSIONS

The present study did not show that additional hemodynamic and biologic effects of stents designed for neck remodeling were enough to enhance progressive occlusion and prevent the recanalization of unruptured aneurysms. Our finding suggests that stent placement provides no better long-term angiographic outcomes for unruptured aneurysms with an unfavorable configuration for coiling.

Green tea consumption, abdominal obesity as related factors of lacunar infarction in Korean women

OBJECTIVES

Our purpose was to evaluate interaction of green tea consumption and abdominal obesity as related factors for lacunar infarction in Korean women.

DESIGN

A hospital-based, incident case-control study.

SETTINGS

The Prevention and Managements of Stroke in Women study.

PARTICIPANTS

Cases (n=233) of first incident lacunar infarction were enrolled and matched by age to stroke-free hospital controls (n=204).

MEASUREMENTS

The data were collected through face-to-face interviews by well trained research assistants to assess demographic, medical, lifestyle, marital status, religions status, green tea consumptions, family history of stroke, smoking status, alcohol consumption, meat and vegetable intake frequency, and past history of hypertension. Biochemical analysis, fasting blood specimens for lipid, glucose, and cholesterol level were acquired.

RESULTS

Compared with the non green tea consumer and obese women group, only the green tea consumption and non obese women group had a protective effect of lacunar infarction when adjusted for age, and age plus diet factors (OR, 0.23; 95% CI, 0.09, 0.59; OR, 0.21; 95% CI, 0.08, 0.56 respectively), but lost their significance after adjustment for age, diet factors, vascular risk factors and full model included atherogenic index factors (OR, 0.32; 95% CI, 0.09 to 1.01; OR, 0.49; 95% CI, 0.12, 1.89 respectively).

CONCLUSIONS

The interaction of green tea consumption and non obesity have reduced risk of lacunar infarction, but not after adjustment for age, diet factors, vascular risk factors and atherogenic index. Also individually green tea consumption and abdominal obesity have failed to find an independent relationship with lacunar infarction after adjustment by all risk factors. Green tea consumption and green tea consumption with non obese group seemed to have a protective effect for lacunar infarction. In the results of our study, these results still remain controversial, and then we need further and larger study to get at the root of real causal effect of both relationships.

Endovascular treatment for unruptured intracranial aneurysms in elderly patients: single-center report

BACKGROUND AND PURPOSE

The optimal management of patients with unruptured intracranial aneurysms remains controversial in elderly populations. The aim of this study was to evaluate technical results and clinical outcomes in a single center of consecutive elderly patients with unruptured intracranial aneurysms treated with endovascular embolization.

MATERIALS AND METHODS

Between May 2003 and February 2010, 96 patients older than 70 years (men, 16 patients; women, 80 patients; mean age, 73 years) with 122 saccular unruptured intracranial aneurysms were treated in our hospital with an endovascular approach. The endovascular procedures and technique, angiographic follow-up, and complications were evaluated.

RESULTS

Successful embolizations without complications were completed in 95.9%. Five patients had procedure-related events, including thromboembolism in 1 patient, aneurysm perforation during the procedure in 1, and 3 postoperative transient minor symptoms (headache, otalgia, and trigeminal pain) in 3. The degree of occlusion of the treated aneurysm was complete in 46.7%; there was a small neck remnant in 40.9% and residual filling in 12.2%. Imaging (MR angiography) follow-up was performed in 68.7% of the patients. The mean follow-up duration was 19.4 months (range, 5-57 months). Fifty-five patients (93.9%) showed no interval change of the residual neck. Four (6%) demonstrated recanalizations, all of which were successfully recoiled.

CONCLUSIONS

Endovascular treatment of unruptured intracranial aneurysms in patients older than 70 years of age appears to be safe. Favorable outcomes with low morbidities may replace surgery or conservative treatment as an active management alternative.

Two-year follow-up of contrast stasis within the sac in unruptured aneurysm coil embolization: progressive thrombosis or enlargement?

BACKGROUND AND PURPOSE

The fate of contrast stasis within an aneurysmal sac after coiling has not been established. We followed and evaluated the potential risks of recanalization of unruptured aneurysms embolized with BPCs for 2 years.

MATERIALS AND METHODS

A total of 301 unruptured aneurysms in 252 patients were treated with BPCs. Contrast stasis was observed on initial postembolization angiograms in 104 (34.6%) of these aneurysms. For follow-up, skull images by an angiographic unit (at 3, 9, 15, and 21 months), CE-MRA including TOF source images (at 6, 12, and 18 months), and DSA (at 24 months) were used.

RESULTS

In 89 (85.6%) of the 104 aneurysms with contrast stasis, the stasis disappeared on 6-month MRAs and occlusions remained unchanged without recanalization for 2 years. In the remaining 15 (14.4%), recanalization occurred during follow-up. The presence of contrast stasis was not found to be associated with the obliteration rate (P = .641) or packing attenuation (aneurysms without contrast stasis 30.7% ± 11.18 versus aneurysms with contrast stasis 33.0% ± 12.11, P = .113). Contrast stasis was not found to be a risk factor for recanalization (15/104 [14.4%] versus 29/197 [14.7%], P = 1.000).

CONCLUSIONS

Contrast stasis is a benign angiographic finding that can disappear within 6 months on follow-up MRA. In addition, contrast stasis was not found to be associated with a low obliteration rate or packing attenuation or to be a risk factor for recanalization. The present study shows that aneurysms with contrast stasis on initial postembolization angiograms are no more likely to recanalize than aneurysms without contrast stasis.

Isolation and characterization of microsatellite loci from rock shell, Thais clavigera

Imposex (superimposition of male genital organs on female phenotype) of the rock shell or whelk, Thais clavigera, shows typical evidence of endocrine disruption by organotin compounds within inter-tidal zones polluted by such compounds. It will be informative to see how low fertility caused by imposex of this species finally affects the genetic diversity of polluted populations. For future use in population genetic research of the rock shell, we report the isolation and characteristics of 11 highly polymorphic microsatellite markers with a mean of 11.7 alleles per locus. We observed heterozygosities of these sequences ranging from 0.43 to 0.95. These markers will be useful for future ecological genetic studies of rock shell.