Recruitment of hippocampal and thalamic pathways to the central amygdala in the control of feeding behavior under novelty

It is adaptive to restrict eating under uncertainty, such as during habituation to novel foods and unfamiliar environments. However, sustained restrictive eating can become maladaptive. Currently, the neural substrates of restrictive eating are poorly understood. Using a model of feeding avoidance under novelty, our recent study identified forebrain activation patterns and found evidence that the central nucleus of the amygdala (CEA) is a core integrating node. The current study analyzed the activity of CEA inputs in male and female rats to determine if specific pathways are recruited during feeding under novelty. Recruitment of direct inputs from the paraventricular nucleus of the thalamus (PVT), the infralimbic cortex (ILA), the agranular insular cortex (AI), the hippocampal ventral field CA1, and the bed nucleus of the stria terminals (BST) was assessed with combined retrograde tract tracing and Fos induction analysis. The study found that during consumption of a novel food in a novel environment, larger number of neurons within the PVTp and the CA1 that send monosynaptic inputs to the CEA were recruited compared to controls that consumed familiar food in a familiar environment. The ILA, AI, and BST inputs to the CEA were similarly recruited across conditions. There were no sex differences in activation of any of the pathways analyzed. These results suggest that the PVTp-CEA and CA1-CEA pathways underlie feeding inhibition during novelty and could be potential sites of malfunction in excessive food avoidance.

The Accuracy of Intraoral Registration for Dynamic Surgical Navigation in the Edentulous Maxilla

PURPOSE

Despite the high clinical accuracy of dynamic navigation, inherent sources of error exist. The purpose of this study was to improve the accuracy of dynamic navigated surgical procedures in the edentulous maxilla by identifying the optimal configuration of intra-oral points that results in the lowest possible registration error for direct clinical implementation.

MATERIALS AND METHODS

Six different 4-area configurations were tested by 3 operators against positive and negative controls (8-areas and 3-areas, respectively) using a skull model. The two dynamic navigation systems (X-Guide® and NaviDent®) and the two registration methods (bone surface tracing and fiducial markers) produced four registration groups. The accuracy of the registration was checked at the frontal process of the zygoma. Intra- and inter- operator reliability for each registration group were reported. Multiple comparisons were conducted to find the best configuration with the minimum registration error.

RESULTS

Ranking revealed one configuration in the tracing groups (Conf.3) and two configurations in the fiducial groups (Conf.3 and Conf.5) that had the best accuracy. When the inferior surfaces of the zygomatic buttress were excluded, fiducial registration produced better accuracy with both systems (p 0.006 and <0.0001). However, tracing 1 cm areas at these surfaces bilaterally resulted in similar registration accuracy as placing fiducial markers there (p 0.430 and 0.237). NaviDent® performed generally better (p 0.049, 0.001 and 0.002) albeit having a wider margin of uncertainty in the obtained values. Changing the distribution of the 4 tracing areas or fiducial markers had a less pronounced effect with X-Guide® than with the NaviDent® system.

CONCLUSION

For edentulous maxillary surgeries, 4 fiducial markers placed according to configuration 3 or 5 result in the lowest registration error. Where implants are being placed bilaterally, an additional 2 sites may reduce the error further. For bilateral zygomatic implant placement, it is optimal to place 2 fiducials on the inferior surfaces of the maxillary tuberosities, other 2 on their buccal surfaces, and 2 on the anterior labial surface of the alveolar bone. Utilising the inferior zygomatic buttress is recommended over the inferior maxillary tuberosities in other types of maxillary surgeries.

Unraveling the chemical fingerprint of the Miami River sources: Insights from high-resolution mass spectrometry and nontarget analysis

This study investigated the chemical composition of waters in the heavily urbanized and historically polluted Miami River, Florida. The goal was to assess the different water sources and anthropogenic influence in this managed area using nontarget analysis (NTA) combined with high-resolution mass spectrometry (HRMS). Surface water samples were collected from 10 sites during five sampling events in the wet season of 2021 and 2022. The HRMS data was processed using Compound Discoverer™ version 3.3, and the results were analyzed using techniques including Principal Component Analysis and Kendrick Mass Defect plots. Results showed a gradient change in the chemical composition from the Everglades to Biscayne Bay endmembers. The Seybold Canal, an adjacent canal, was consistently identified as a unique source of contaminants, contributing its own specific set of tracers. Increased presence and intensity of organic contaminants along the waterway was observed, indicating significant anthropogenic influence in the area. The NTA and post-processing were evaluated for reproducibility, demonstrating robustness with a 71.2% average reproducibility for compounds detected in 3 out of 5 sampling trips. A detection frequency of 80% (4 out of 5) was the set criterion for detected compounds suggested as tracers. To prioritize samples, hierarchical cluster analysis was employed, and potential tracers for each water source were determined. Tracers included natural products and agricultural herbicides and insecticides for the Everglades, anthropogenic contaminants for the Seybold Canal, and a lack of unique tracers for Biscayne Bay. Additionally, urban-influenced contaminants such as flame retardants, insect repellents, pharmaceuticals, and non-agricultural herbicides were identified along the river. This study highlights the impact of human activities on the Miami River and demonstrates the effectiveness of NTA in differentiating and tracking water sources. The results emphasize the importance of reproducibility in NTA and provide guidance on implementing monitoring strategies by prioritizing samples based on chemical compositions.

Altered Metabolism During the Dark Period in Drosophila Short Sleep Mutants

Sleep is an almost universally required state in biology. Disrupted sleep has been associated with adverse health risks including metabolic perturbations. Sleep is in part regulated via circadian mechanisms, however, metabolic dysfunction at different times of day arising from sleep disruption is unclear. We used targeted liquid chromatography-mass spectrometry to probe metabolic alterations using high-resolution temporal sampling of two Drosophila short sleep mutants, fumin and sleepless, across a circadian day. Discriminant analyses revealed overall distinct metabolic profiles for mutants when compared to a wild type dataset. Altered levels of metabolites involved in nicotinate/nicotinamide, alanine, aspartate, and glutamate, glyoxylate and dicarboxylate metabolism, and the TCA cycle were observed in mutants suggesting increased energetic demands. Furthermore, rhythmicity analyses revealed fewer 24 hr rhythmic metabolites in both mutants. Interestingly, mutants displayed two major peaks in phases while wild type displayed phases that were less concerted. In contrast to 24 hr rhythmic metabolites, an increase in the number of 12 hr rhythmic metabolites was observed in fumin while sleepless displayed a decrease. These results support that decreased sleep alters the overall metabolic profile with short sleep mutants displaying altered metabolite levels associated with a number of pathways in addition to altered neurotransmitter levels.

Subserosal Indocyanine Green Plus Submucosal Carbon Nanoparticle Navigated Laparoscopic Gastrectomy (DANCE-01): a Cohort Study

BACKGROUND

Indocyanine green (ICG) and carbon nanoparticle (CN) have been widely used for radical gastrectomy. However, synchronous application of ICG and CN in gastrectomy has not been tried yet. For the first time, we herein reported a novel strategy using dual tracers in laparoscopic radical gastrectomy.

METHODS

This is a single-center, single-armed, prospective study. For each qualified patient, submucosal CN was injected the day before surgery, and subserosal ICG was injected immediately before surgery. Standard D2 laparoscopic gastrectomy and lymph node examination were subsequently performed. Demographics, lymph nodes (LNs) and postoperative outcome were collected for analysis. To analyze the safety and efficacy of this novel strategy, two contemporary historic control groups using single tracer were established.

RESULTS

A total of 60 patients underwent dual tracer laparoscopic gastrectomy and were divided into distal (n = 41) and total (n = 19) groups. An average of 53.3 and 62.2 LNs was harvested from two groups, respectively. The average operation duration was 213.3 and 250.0 min, and intra-operative blood loss was 100.2 ml and 94.7 ml. None received combined organ resection. Margin negativity and R0 resection were achieved in all patients. Three (7.3%) complications occurred in distal group. None required second operation or deceased. Postoperative hospitalization was 9.7 and 9.6 days, respectively. Compared to single tracer, more LNs (p < 0.01), shorter operation time (p < 0.01), less blood lost (p < 0.01) and accelerated postoperative recovery (p < 0.01) were observed in dual tracer group.

CONCLUSIONS

We propose a novel, feasible and safe tracing strategy for laparoscopic gastrectomy.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2100051309).

Tracing the transmission of mpox through wastewater surveillance in Southeast Asia

High population density and tourism in Southeast Asia increase the risk of mpox due to frequent interpersonal contacts. Our wastewater surveillance in six Southeast Asian countries revealed positive signals for Monkeypox virus (MPXV) DNA, indicating local transmission. This alerts clinicians and helps allocate resources like testing, vaccines and therapeutics in resource-limited countries.

Tracing and tracking filamentous structures across scales: A systematic review

Filamentous structures are ubiquitous in nature, are studied in diverse scientific fields, and span vastly different spatial scales. Filamentous structures in biological systems fulfill different functions and often form dynamic networks that respond to perturbations. Therefore, characterizing the properties of filamentous structures and the networks they form is important to gain better understanding of systems level functions and dynamics. Filamentous structures are captured by various imaging technologies, and analysis of the resulting imaging data addresses two problems: (i) identification (tracing) of filamentous structures in a single snapshot and (ii) characterizing the dynamics (i.e., tracking) of filamentous structures over time. Therefore, considerable research efforts have been made in developing automated methods for tracing and tracking of filamentous structures. Here, we provide a systematic review in which we present, categorize, and discuss the state-of-the-art methods for tracing and tracking of filamentous structures in sparse and dense networks. We highlight the mathematical approaches, assumptions, and constraints particular for each method, allowing us to pinpoint outstanding challenges and offer perspectives for future research aimed at gaining better understanding of filamentous structures in biological systems.

Self-transfers and factors associated with successful tracing among persons lost to follow-up from HIV care, Sheema District, Southwestern Uganda: retrospective medical records review, 2017-2021

BACKGROUND

Due to improved coverage and scale-up of antiretroviral therapy (ART), patients are increasingly transferring between ART-providing sites. Self-transfers may constitute a high proportion of patients considered lost to follow-up (LTFU), and if overlooked when reporting patients who have dropped out of HIV care, may result in an incorrect estimation of retention. We determined the prevalence of self-transfers, and successful tracing, and identified associated factors among people living with HIV (PLHIV) LTFU from care at public health facilities in Sheema District, Southwestern Uganda.

METHODS

We conducted a cross-sectional retrospective medical records review during February and March 2022. We included records of all PLHIV who were LTFU from 2017 to 2021, and who were registered at government-owned ART clinics in Sheema District. LTFU was considered for those who were not taking ART refills for a period of ≥ 3 months. We abstracted demographic and clinical data from medical records at the selected clinics. Participants were traced via phone calls or in-person to ascertain the outcomes of LTFU. We performed multivariate modified Poisson regression to identify factors associated with self-transfer, and successful tracing.

RESULTS

Overall, 740 patients were identified as LTFU from three ART-providing clinics; of these, 560 (76%) were self-transfers. The mean age was 30 (SD ± 10) years, and most (69%, n = 514) were female; the majority (87%, 641/740) were successfully traced. Age (adjusted prevalence ratio [aPR] = 1.13, 95% CI 1.01-1.25, P = 0.026 for those aged 18-30 years compared to > 30 years), female sex (aPR = 1.18, 95% CI 1.11-1.25, P < 0.001), and having WHO clinical stage 1-2 (aPR = 2.34, 95% CI 1.89-3.91, P < 0.001) were significantly associated with self-transfer. Presence of a phone contact in the patient's file (aPR = 1.10, 95% CI 1.01-1.90, P = 0.026) was associated with successful tracing of the patients considered LTFU.

CONCLUSION

Self-transfers accounted for the majority of patients recorded as LTFU, highlighting the need to account for self-transfers among patients considered LTFU, to accurately estimate retention in care. ART-providing facilities should regularly update contact information for PLHIV to enable successful tracing, in the event that the patients are LTFU. This calls for a health-tracking system that easily identifies self-transfers across ART-providing clinics using unique patient identifiers.

SARS-CoV-2 viral load is associated with risk of transmission to household and community contacts

Background

Factors that lead to successful SARS-CoV-2 transmission are still not well described. We investigated the association between a case’s viral load and the risk of transmission to contacts in the context of other exposure-related factors.

Methods

Data were generated through routine testing and contact tracing at a large university. Case viral loads were obtained from cycle threshold values associated with a positive polymerase chain reaction test result from October 1, 2020 to April 15, 2021. Cases were included if they had at least one contact who tested 3–14 days after the exposure. Case-contact pairs were formed by linking index cases with contacts. Chi-square tests were used to evaluate differences in proportions of contacts testing positive. Generalized estimating equation models with a log link were used to evaluate whether viral load and other exposure-related factors were associated with a contact testing positive.

Results

Median viral load among the 212 cases included in the study was 5.6 (1.8–10.4) log₁₀ RNA copies per mL of saliva. Among 365 contacts, 70 (19%) tested positive following their exposure; 36 (51%) were exposed to a case that was asymptomatic or pre-symptomatic on the day of exposure. The proportion of contacts that tested positive increased monotonically with index case viral load (12%, 23% and 25% corresponding to < 5, 5–8 and > 8 log₁₀ copies per mL, respectively; X² = 7.18, df = 2, p = 0.03). Adjusting for cough, time between test and exposure, and physical contact, the risk of transmission to a close contact was significantly associated with viral load (RR = 1.27, 95% CI 1.22–1.32).

Conclusions

Further research is needed to understand whether these relationships persist for newer variants. For those variants whose transmission advantage is mediated through a high viral load, public health measures could be scaled accordingly. Index cases with higher viral loads could be prioritized for contact tracing and recommendations to quarantine contacts could be made according to the likelihood of transmission based on risk factors such as viral load.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07663-1.

Cerebellar Transcranial Direct Current Stimulation Reconfigures Brain Networks Involved in Motor Execution and Mental Imagery

Transcranial direct current stimulation (tDCS) is growingly applied to the cerebellum to modulate the activity of cerebellar circuitry, affecting both motor and cognitive performances in a polarity-specific manner. The remote effects of tDCS are mediated in particular via the dentato-thalamo-cortical pathway. We showed recently that tDCS of the cerebellum exerts dynamic effects on resting state networks. We tested the neural hypothesis that tDCS reconfigurates brain networks involved in motor execution (ME) and motor mental imagery (MMI). We combined tDCS applied over the right cerebellum and fMRI to investigate tDCS-induced reconfiguration of ME- and MMI-related networks using a randomized, sham-controlled design in 21 right-handed healthy volunteers. Subjects were instructed to draw circles at comfortable speed and to imagine drawing circles with their right hand. fMRI data were recorded after real anodal stimulation (1.5 mA, 20 min) or sham tDCS. Real tDCS compared with SHAM specifically reconfigurated the functional links between the main intrinsic connected networks, especially the central executive network, in relation with lobule VII, and the salience network. The right cerebellum mainly influenced prefrontal and anterior cingulate areas in both tasks, and improved the overt motor performance. During MMI, the cerebellum also modulated the default-mode network and associative visual areas. These results demonstrate that tDCS of the cerebellum represents a novel tool to modulate cognitive brain networks controlling motor execution and mental imagery, tuning the activity of remote cortical regions. This approach opens novel doors for the non-invasive neuromodulation of disorders involving cerebello-thalamo-cortical paths.

biPACT: A method for three-dimensional visualization of mouse spinal cord circuits of long segments with high resolution

BACKGROUND

The spatial complexity of neuronal circuits in the central nervous system is a hurdle in understanding and treating brain and spinal cord injury (SCI). Although several methods have recently been developed to render the spinal cord transparent and label specific neural circuits, three-dimensional visualization of long segments of spinal cord with high resolution remains challenging for SCI researchers.

NEW METHOD

We present a method that combines tissue staining of neuronal tracts traced with biotinylated dextran amine (BDA) and a modified passive clarity clearing protocol to describe individual fibers in long segments of mouse spinal cord.

RESULTS

Corticospinal tract was traced with BDA with a mouse model of thoracic spinal cord injury. The spinal cord was stained and cleared in two weeks with four solutions: staining solution, hydrogel solution, clearing solution, and observation solution. The samples were observed with a light-sheet microscope, and three-dimensional reconstruction was performed with ImageJ software. High resolution-images comparable with tissue sections were obtained continuously and circumferentially. By tiling, it was possible to obtain high-resolution images of long segments of the spinal cord. The tissue could be easily re-stained in case of fading.

COMPARISON WITH EXISTING METHODS

The present method does not require special equipment such as vacuum devices, can label specific circuits without genetic technology, and re-staining rounds can be easily implemented.

CONCLUSIONS

By using simple neural staining and clearing methods, it was possible to acquire a wide range of high-resolution three-dimensional images of the spinal cord.

Challenges in tracing treatment non-adherent persons with mental illness: Experiences from a rural community mental health center, India

Identification, enrollment, and retention in treatment are challenging processes in mental health care. The present paper highlights the challenges in tracing and reenrolling non-adherent persons with mental illness for treatment in a rural community mental health center. Unclear address, phone numbers not in use, relocation from the given address, no further contact details etc. are the barriers to trace and make the home visits. A detailed review of the medical record, having a network with the village informal health care workers and groups, utilizing peer group support, etc., are the facilitators for tracing the treatment non-adherent persons in the community.

Enjoy your observability: an industrial survey of microservice tracing and analysis

Microservice systems are often deployed in complex cloud-based environments and may involve a large number of service instances being dynamically created and destroyed. It is thus essential to ensure observability to understand these microservice systems' behaviors and troubleshoot their problems. As an important means to achieve the observability, distributed tracing and analysis is known to be challenging. While many companies have started implementing distributed tracing and analysis for microservice systems, it is not clear whether existing approaches fulfill the required observability. In this article, we present our industrial survey on microservice tracing and analysis through interviewing developers and operation engineers of microservice systems from ten companies. Our survey results offer a number of findings. For example, large microservice systems commonly adopt a tracing and analysis pipeline, and the implementations of the pipeline in different companies reflect different tradeoffs among a variety of concerns. Visualization and statistic-based metrics are the most common means for trace analysis, while more advanced analysis techniques such as machine learning and data mining are seldom used. Microservice tracing and analysis is a new big data problem for software engineering, and its practices breed new challenges and opportunities.

Diffusion MRI and anatomic tracing in the same brain reveal common failure modes of tractography

Anatomic tracing is recognized as a critical source of knowledge on brain circuitry that can be used to assess the accuracy of diffusion MRI (dMRI) tractography. However, most prior studies that have performed such assessments have used dMRI and tracer data from different brains and/or have been limited in the scope of dMRI analysis methods allowed by the data. In this work, we perform a quantitative, voxel-wise comparison of dMRI tractography and anatomic tracing data in the same macaque brain. An ex vivo dMRI acquisition with high angular resolution and high maximum b-value allows us to compare a range of q-space sampling, orientation reconstruction, and tractography strategies. The availability of tracing in the same brain allows us to localize the sources of tractography errors and to identify axonal configurations that lead to such errors consistently, across dMRI acquisition and analysis strategies. We find that these common failure modes involve geometries such as branching or turning, which cannot be modeled well by crossing fibers. We also find that the default thresholds that are commonly used in tractography correspond to rather conservative, low-sensitivity operating points. While deterministic tractography tends to have higher sensitivity than probabilistic tractography in that very conservative threshold regime, the latter outperforms the former as the threshold is relaxed to avoid missing true anatomical connections. On the other hand, the q-space sampling scheme and maximum b-value have less of an impact on accuracy. Finally, using scans from a set of additional macaque brains, we show that there is enough inter-individual variability to warrant caution when dMRI and tracer data come from different animals, as is often the case in the tractography validation literature. Taken together, our results provide insights on the limitations of current tractography methods and on the critical role that anatomic tracing can play in identifying potential avenues for improvement.

Student returnees from China's COVID-19 epicenter: Spatio-temporal movement and impact of tracing

At the initial stage of COVID-19 outbreak, tracing returnees from Wuhan – the epicenter of the disease – is a major strategy in each province of China to contain its spread. However, scholars are yet to assess the impact of tracing on individuals. Drawing upon a large-scale survey with students from four major universities in Wuhan, we investigate individual experiences with tracing activities at government and community levels and the impacts on students’ socio-psychological wellbeing. Findings indicate that tracing is likely to increase the risks of privacy infringement, verbal slur, and warning at residence; and students experience moderate-to-high levels of anxiety and fear. Improved public health measures are therefore necessary to balance the twin goals of containing disease and alleviating unintended consequences of tracing.

Tracing people living with HIV who are lost to follow-up at ART programs in Southern Africa: A sampling-based cohort study in six countries

BACKGROUND

Attrition threatens the success of antiretroviral therapy (ART). In this cohort study, we examined outcomes of people living with HIV (PLHIV) lost to follow-up (LTFU) 2014-2017 at ART programs in Southern Africa.

METHODS

We confirmed LTFU (missed appointment for ≥60 or ≥90 days, according to local guidelines) by checking medical records and used a standardized protocol to trace a weighted random sample of PLHIV who were LTFU in eight ART programs in Lesotho, Malawi, Mozambique, South Africa, Zambia and Zimbabwe, 2017-2019. We ascertained vital status and identified predictors of mortality using logistic regression, adjusted for sex, age, time on ART, time since LTFU, travel time, and urban or rural setting.

RESULTS

Among 3,256 PLHIV, 385 (12%) were wrongly categorized as LTFU and 577 (17%) had missing contact details. We traced 2,294 PLHIV (71%) by phone calls, home visits or both: 768 (34% of 2,294) were alive and in care, including 385 (17%) silent transfers to another clinic; 528 (23%) were alive without care or unknown care; 252 (11%) had died. Overall, the status of 1,323 (41% of 3,256) PLHIV remained unknown. Mortality was higher in men than women, higher in children than in young people or adults, higher in PLHIV who had been on ART <1 year or lost >1 year, living further from the clinic or in rural areas. Results were heterogeneous across sites.

CONCLUSIONS

Our study highlights the urgent need for better medical record systems at HIV clinics and rapid tracing of PLHIV who are LTFU.

A hover view over effectual approaches on pandemic management for sustainable cities - The endowment of prospective technologies with revitalization strategies

The COVID-19 pandemic affects all of society and hinders day-to-day activities from a straightforward perspective. The pandemic has an influential impact on almost everything and the characteristics of the pandemic remain unclear. This ultimately leads to ineffective strategic planning to manage the pandemic. This study aims to elucidate the typical pandemic characteristics in line with various temporal phases and its associated measures that proved effective in controlling the pandemic. Besides, an insight into diverse country's approaches towards pandemic and their consequences is provided in brief. Understanding the role of technologies in supporting humanity gives new perspectives to effectively manage the pandemic. Such role of technologies is expressed from the viewpoint of seamless connectivity, rapid communication, mobility, technological influence in healthcare, digitalization influence, surveillance and security, Artificial Intelligence (AI), and Internet of Things (IoT). Furthermore, some insightful scenarios are framed where the full-fledged implementation of technologies is assumed, and the reflected pandemic impacts in such scenarios are analyzed. The framed scenarios revolve around the digitalized energy sector, an enhanced supply chain system with effective customer-retailer relationships to support the city during the pandemic scenario, and an advanced tracking system for containing virus spread. The study is further extended to frame revitalization strategies to highlight the expertise where significant attention needs to be provided in the post-pandemic period as well as to nurture sustainable development. Finally, the current pandemic scenario is analyzed in terms of occurred changes and is mapped into SWOT factors. Using Fuzzy Technique for Order of Preference by Similarity to Ideal Solution based Multi-Criteria Decision Analysis, these SWOT factors are analyzed to determine where prioritized efforts are needed to focus so as to traverse towards sustainable cities. The results indicate that the enhanced crisis management ability and situational need to restructure the economic model emerges to be the most-significant SWOT factor that can ultimately support humanity for making the cities sustainable.

Circle drawing and tracing dataset for evaluation of fine motor control

We introduce a motion dataset from healthy human subjects (n = 125) performing two fine motor control tasks on a graphic tablet, namely circle drawing and circle tracing. The article reports the methods and materials used to capture the motion data. The method for data acquisition is the same as the one used to investigate some aspects of fine motor control in healthy subjects in the paper by Cohen et al. (2018) “Precision in drawing and tracing tasks: Different measures for different aspects of fine motor control” (https://doi.org/10.1016/j.humov.2018.08.004) [1]. The dataset shared here contains new raw files of the two-dimensional motion data, as well information on the participants (gender, age, laterality index). These data could be instrumental for assessing other aspects of fine motor control, such as speed-accuracy tradeoff, speed-curvature power law, etc., and/or test machine learning algorithms for e.g., task classification.

Dorsal prefrontal and premotor cortex of the ferret as defined by distinctive patterns of thalamo-cortical projections

Recent studies of the neurobiology of the dorsal frontal cortex (FC) of the ferret have illuminated its key role in the attention network, top-down cognitive control of sensory processing, and goal directed behavior. To elucidate the neuroanatomical regions of the dorsal FC, and delineate the boundary between premotor cortex (PMC) and dorsal prefrontal cortex (dPFC), we placed retrograde tracers in adult ferret dorsal FC anterior to primary motor cortex and analyzed thalamo-cortical connectivity. Cyto- and myeloarchitectural differences across dorsal FC and the distinctive projection patterns from thalamic nuclei, especially from the subnuclei of the medial dorsal (MD) nucleus and the ventral thalamic nuclear group, make it possible to clearly differentiate three separate dorsal FC fields anterior to primary motor cortex: polar dPFC (dPFCpol), dPFC, and PMC. Based on the thalamic connectivity, there is a striking similarity of the ferret's dorsal FC fields with other species. This possible homology opens up new questions for future comparative neuroanatomical and functional studies.

[Laboratory testing and tracing analysis of a typhoid epidemic in Jiangyin city, Jiangsu Province]

To conduct outbreak identification and transmission factor analysis of typhoid epidemic occurred in Xinqiao town, Jiangyin city from June to September 2016. A total of 14 strains of Salmonella typhi isolated from confirmed cases were collected, and 65 external environment samples and 13 food samples related to the outbreak were taken. Real-time PCR was used to detect specific gene of Salmonella typhi in the samples. Conventional method was used to isolate strains. The strains isolated from both the samples and patients in the epidemic were subjected to antimicrobial susceptibility testing and PFGE molecular characteristics. Salmonella typhi strain was isolated from one external sample (well water of a deli processing plant). The results of drug susceptibility showed that 15 strains were resistant to nalidixic acid. A total of 15 strains of Salmonella typhi were divided into 2 molecular patterns by pulsed field gel electrophoresis. The fingerprints of PFGE from the 13 patients and the environmental isolate were completely consistent, and there was one band difference from the other patient isolate. Combined with the epidemiological investigation and laboratory test results, it was determined that the outbreak was caused by genetic clone of the same Salmonella typhi. Food processing plant should be one of the key links.

Basal forebrain subcortical projections

The basal forebrain (BF) contains at least three distinct populations of neurons (cholinergic, glutamatergic, and GABA-ergic) across its different regions (medial septum, diagonal band, magnocellular preoptic area, and substantia innominata). Much attention has focused on the BF's ascending projections to cortex, but less is known about descending projections to subcortical regions. Given the neurochemical and anatomical heterogeneity of the BF, we used conditional anterograde tracing to map the patterns of subcortical projections from multiple BF regions and neurochemical cell types using mice that express Cre recombinase only in cholinergic, glutamatergic, or GABAergic neurons. We confirmed that different BF regions innervate distinct subcortical targets, with more subcortical projections arising from neurons in the caudal and lateral BF (substantia innominata and magnocellular preoptic area). Additionally, glutamatergic and GABAergic BF neurons have distinct patterns of descending projections, while cholinergic descending projections are sparse. Considering the intensity of glutamatergic and GABAergic descending projections, the BF likely acts through subcortical targets to promote arousal, motivation, and other behaviors.

Cortical bone is an extraneuronal site of norepinephrine uptake in adult mice

The sympathetic nervous system is a major efferent pathway through which the central nervous system controls the function of peripheral organs. Genetic and pharmacologic evidence in mice indicated that stimulation of the β2 adrenergic receptor (β2AR) in osteoblasts promotes bone loss, leading to the paradigm that high sympathetic nervous activity is deleterious to bone mass. However, considerably less data exist to understand the putative impact of endogenous norepinephrine (NE), released by sympathetic nerves, on bone homeostasis. In this study, we investigated the in vivo expression and activity of the norepinephrine transporter (NET), a membrane pump known to actively uptake NE from the extracellular space in presynaptic neurons. Consistent with previously published in vitro data showing NET uptake activity in differentiated osteoblasts, we were able to detect active NET-specific NE uptake in the mouse cortical bone compartment in vivo. This uptake was the highest in young mice and accordingly with an age-related reduction in NET uptake, NE bone content increased whereas Net RNA and protein expression decreased with age. Histologically, NET expression in adult mouse bones was detected in osteocytes via immunofluorescence. Lastly, taking advantage of tissue-specific fluorescent reporter mice, we used CLARITY imaging and light sheet microscopy to visualize the 3D distribution of sympathetic fibers in whole mount preparations of bone tissues. These analyses allowed us to detect tyrosine hydroxylase (TH)-positive sympathetic nerve fibers penetrating the cortical bone, where NET+ osteocytes reside. Together, these in vitro results support the existence of an age-dependent extraneuronal and osteocytic function of NET with potential to buffer the bone catabolic action of endogenous NE released by sympathetic nerves in vivo.

She knows that she will not come back: tracing patients and new thresholds of collective surveillance in PMTCT Option B

BACKGROUND

Malawi, Uganda, and Zimbabwe have recently adopted a universal 'test-and-treat' approach to the prevention of mother-to-child transmission of HIV (Option B+). Amongst a largely asymptomatic population of women tested for HIV and immediately started on antiretroviral treatment (ART), a relatively high number are not retained in care; they are labelled 'defaulters' or 'lost-to-follow-up' patients.

METHODS

We draw on data collected as part of a study looking at ART decentralization (Lablite) to reflect on the spaces created through the instrumentalization of community health workers (CHWs) for the purpose of bringing women who default from Option B+ back into care. Data were collected through semi-structured interviews with CHWs who are designated to trace Option B+ patients in Uganda, Malawi and Zimbabwe.

FINDINGS

Lost to follow up women give a range of reasons for not coming back to health facilities and often implicitly choose not to be traced by providing a false address at enrolment. New strategies have sought to utilize CHWs' liminal positionality - situated between the experience of living with HIV, having established local social ties, and being a caretaker - in order to track 'defaulters'. CHWs are often deployed without adequate guidance or training to protect confidentiality and respect patients' choice.

CONCLUSIONS

CHWs provide essential linkages between health services and patients; they embody the role of 'extension workers', a bridge between a novel health policy and 'non-compliant patients'. Option B+ offers a powerful narrative of the construction of a unilateral 'moral economy', which requires the full compliance of patients newly initiated on treatment.

Tracing GFP-labeled WJMSCs in vivo using a chronic salpingitis model: an animal experiment

Background

The present study was conducted to evaluate the distribution of Wharton’s jelly-derived mesenchymal stem cells (WJMSCs) and their repairing function on the oviduct.

Methods

WJMSCs were transfected with the LV3-GFP-PURO lentivirus. Female New Zealand rabbits (n = 24) were divided randomly into control A and B groups and experimental C and D groups to establish inflammation models. Sterile saline solution or WJMSCs were injected into rabbits via ear veins and/or genital tract perfusion once weekly for 3 weeks. All rabbits were humanely sacrificed 1 week after the last perfusion to collect the oviduct, uterus, liver, and bladder for examination. Green fluorescent protein (GFP) and cytokeratin 7 (CK7) were imaged using a Leica Qwin Plus V3 fluorescence confocal microscope and analyzed as mean optical densities in an Image-Pro Plus analysis system.

Results

We found that lentivirus expressing the GFP gene produced an efficient transfection. The mean optical density values of GFP and CK7 in the oviducts were higher in the experimental D group than those in the control A and experimental C groups. No GFP fluorescence deposits occurred in the bladder of the control A group or experimental C group. Colocalization of CK7 and WJMSCs was observed in the oviducts in all groups.

Conclusions

WJMSCs exhibited homing characteristics and migrated to the injured oviduct to promote epithelial cell growth. Additionally, local treatment resulted in higher efficiency.

Updating vital status by tracking in the community among patients with epidemic Kaposi sarcoma who are lost to follow-up in sub-Saharan Africa

BACKGROUND

Throughout most of sub-Saharan Africa (and, indeed, most resource-limited areas), lack of death registries prohibits linkage of cancer diagnoses and precludes the most expeditious approach to determining cancer survival. Instead, estimation of cancer survival often uses clinical records, which have some mortality data but are replete with patients who are lost to follow-up (LTFU), some of which may be caused by undocumented death. The end result is that accurate estimation of cancer survival is rarely performed. A prominent example of a common cancer in Africa for which survival data are needed but for which frequent LTFU has precluded accurate estimation is Kaposi sarcoma (KS).

METHODS

Using electronic records, we identified all newly diagnosed KS among HIV-infected adults at 33 primary care clinics in Kenya, Uganda, Nigeria, and Malawi from 2009 to 2012. We determined those patients who were apparently LTFU, defined as absent from clinic for ≥90 days at database closure and unknown to be dead or transferred. Using standardized protocols which included manual chart review, telephone calls, and physical tracking in the community, we attempted to update vital status amongst patients who were LTFU.

RESULTS

We identified 1222 patients with KS, of whom 440 were LTFU according to electronic records. Manual chart review revealed that 18 (4.1%) were classified as LFTU due to clerical error, leaving 422 as truly LTFU. Of these 422, we updated vital status in 78%; manual chart review was responsible for updating in 5.7%, telephone calls in 26%, and physical tracking in 46%. Among 378 patients who consented at clinic enrollment to be tracked if they became LTFU and who had sufficient geographic contact/locator information, we updated vital status in 88%. Duration of LTFU was not associated with success of tracking, but tracking success was better in Kenya than the other sites.

CONCLUSION

It is feasible to update vital status in a large fraction of patients with HIV-associated KS in sub-Saharan Africa who have become LTFU from clinical care. This finding likely applies to other cancers as well. Updating vital status amongst lost patients paves the way towards accurate determination of cancer survival.

Assessment of motor skill task performance with a task progress-weighted error measure

A quantitative measure has been developed for the assessment and skill ordering of target-cued motor control and coordination task performances. It is similar to the classical root mean square error (RMSE) measure but modified with task progress weighting that attenuates with target proximity to its destination and amplifies as data sampling occurrences accumulate prior to task completion. The measure has the same mathematical form whether the task design is of the tracing type or of the tracking type, and thus can be used in cross task type comparisons. The new measure is applied to a few simple hypothetical task performances in order to illustrate some of its properties, and then applied to actual experimental data from a tracing task and a tracking task to demonstrate its use.

The impact of catchment source group classification on the accuracy of sediment fingerprinting outputs

The objective classification of sediment source groups is at present an under-investigated aspect of source tracing studies, which has the potential to statistically improve discrimination between sediment sources and reduce uncertainty. This paper investigates this potential using three different source group classification schemes. The first classification scheme was simple surface and subsurface groupings (Scheme 1). The tracer signatures were then used in a two-step cluster analysis to identify the sediment source groupings naturally defined by the tracer signatures (Scheme 2). The cluster source groups were then modified by splitting each one into a surface and subsurface component to suit catchment management goals (Scheme 3). The schemes were tested using artificial mixtures of sediment source samples. Controlled corruptions were made to some of the mixtures to mimic the potential causes of tracer non-conservatism present when using tracers in natural fluvial environments. It was determined how accurately the known proportions of sediment sources in the mixtures were identified after unmixing modelling using the three classification schemes. The cluster analysis derived source groups (2) significantly increased tracer variability ratios (inter-/intra-source group variability) (up to 2122%, median 194%) compared to the surface and subsurface groupings (1). As a result, the composition of the artificial mixtures was identified an average of 9.8% more accurately on the 0-100% contribution scale. It was found that the cluster groups could be reclassified into a surface and subsurface component (3) with no significant increase in composite uncertainty (a 0.1% increase over Scheme 2). The far smaller effects of simulated tracer non-conservatism for the cluster analysis based schemes (2 and 3) was primarily attributed to the increased inter-group variability producing a far larger sediment source signal that the non-conservatism noise (1). Modified cluster analysis based classification methods have the potential to reduce composite uncertainty significantly in future source tracing studies.

GAIN: A graphical method to automatically analyze individual neurite outgrowth

BACKGROUND

Neurite outgrowth is a metric widely used to assess the success of in vitro neural stem cell differentiation or neuron reprogramming protocols and to evaluate high-content screening assays for neural regenerative drug discovery. However, neurite measurements are tedious to perform manually, and there is a paucity of freely available, fully automated software to determine neurite measurements and neuron counting. To provide such a tool to the neurobiology, stem cell, cell engineering, and neuroregenerative communities, we developed an algorithm for performing high-throughput neurite analysis in immunofluorescent images.

NEW METHOD

Given an input of paired neuronal nuclear and cytoskeletal microscopy images, the GAIN algorithm calculates neurite length statistics linked to individual cells or clusters of cells. It also provides an estimate of the number of nuclei in clusters of overlapping cells, thereby increasing the accuracy of neurite length statistics for higher confluency cultures. GAIN combines image processing for neuronal cell bodies and neurites with an algorithm for resolving neurite junctions.

RESULTS

GAIN produces a table of neurite lengths from cell body to neurite tip per cell cluster in an image along with a count of cells per cluster.

COMPARISON WITH EXISTING METHODS

GAIN's performance compares favorably with the popular ImageJ plugin NeuriteTracer for counting neurons, and provides the added benefit of assigning neurites to their respective cell bodies.

CONCLUSIONS

In summary, GAIN provides a new tool to improve the robust assessment of neural cells by image-based analysis.

The oxygen isotopic composition of phosphate in river water and its potential sources in the Upper River Taw catchment, UK

The need to reduce both point and diffuse phosphorus pollution to aquatic ecosystems is widely recognised and in order to achieve this, identification of the different pollutant sources is essential. Recently, a stable isotope approach using oxygen isotopes within phosphate (δ¹⁸O_PO4) has been used in phosphorus source tracing studies. This approach was applied in a one-off survey in September 2013 to the River Taw catchment in south-west England where elevated levels of phosphate have been reported. River water δ¹⁸O_PO4 along the main channel varied little, ranging from +17.1 to +18.8‰. This was no >0.3‰ different to that of the isotopic equilibrium with water (Eδ¹⁸O_PO4). The δ¹⁸O_PO4 in the tributaries was more variable (+17.1 to +18.8‰), but only deviated from Eδ¹⁸O_PO4 by between 0.4 and 0.9‰. Several potential phosphate sources within the catchment were sampled and most had a narrow range of δ¹⁸O_PO4 values similar to that of river Eδ¹⁸O_PO4. Discharge from two waste water treatment plants had different and distinct δ¹⁸O_PO4 from one another ranging between +16.4 and +19.6‰ and similar values to that of a dairy factory final effluent (+16.5 to +17.8‰), mains tap water (+17.8 to +18.4‰), and that of the phosphate extracted from river channel bed sediment (+16.7 to +17.6‰). Inorganic fertilizers had a wide range of values (+13.3 to +25.9‰) while stored animal wastes were consistently lower (+12.0 to +15.0‰) than most other sources and Eδ¹⁸O_PO4. The distinct signals from the waste water treatment plants were lost within the river over a short distance suggesting that rapid microbial cycling of phosphate was occurring, because microbial cycling shifts the isotopic signal towards Eδ¹⁸O_PO4. This study has added to the global inventory of phosphate source δ¹⁸O_PO4 values, but also demonstrated the limitations of this approach to identifying phosphate sources, especially at times when microbial cycling is high.

Effect of reduced visual acuity on precision of two-dimensional tracing movements

PURPOSE

We intended to assess consequences of reduced visual acuity for performance in a natural simple motor task (tracing) using objective kinematic performance measures. Specifically, we intended to elucidate the kind of relationship between the task performance and best corrected binocular visual acuity and to determine the threshold of visual acuity when task performance starts to deteriorate.

METHODS

Ninety-five individuals with different best corrected visual acuity participated in the study (age 49±12 years, mean±SD, 27 men and 68 women). The participants manually traced maze-like visual patterns of different spatial complexity presented on the screen of a portable notebook computer using Clinical Kinematic Assessment Tool software. Tracing error was computed as performance measure in each trial with a spatial pattern matching technique - rigid point set registration method.

RESULTS

The segmented linear regression analysis showed that the relation between visual acuity and tracing errors was best described with a regression function having a break point between two data segments. Tracing performance was unaffected by values of visual acuity below 0.2 on logMAR scale, but when logMAR values increased above this critical limit (i.e. when visual acuity is further reduced), tracing errors linearly increased. The rate of the increase of the tracing error correlated with the complexity of visual stimulus shape.

CONCLUSION

Testing of fine motor functions with objective kinematic measures during visuomotor tasks may help differentiating between actual effects of reduced visual acuity on eye-hand coordination in individuals with similar levels of impairment of visual acuity.

Analysis of Fatty Acid Metabolism Using Stable Isotope Tracers and Mass Spectrometry

Cells can synthesize fatty acids by ligating multiple acetyl units from acetyl-CoA. This is followed by desaturation and elongation reactions to produce a variety of fatty acids required for proper cellular functioning. Alternatively, exogenous lipid sources can contribute to cellular fatty acid pools. Here, we present a method based on incorporation of (13)C-carbon from labeled substrates into fatty acids and subsequent mass spectrometry analysis. The resulting labeling patterns can be used to determine (1) (13)C-enrichment of lipogenic acetyl-CoA, (2) the relative contributions of synthesis and uptake, and (3) absolute fatty acid fluxes. We begin by providing a background and general principles regarding the use of stable isotopes to study fatty acid metabolism. We then proceed with detailing procedures for sample preparation and both GC-MS and LC-MS analysis of isotope incorporation. Finally, we discuss the interpretation of the resulting fatty acid-labeling patterns.

Retino-retinal projection in juvenile and young adult rats and mice

Identification of retino-retinal projecting RGCs (ret-ret RGCs) has been accomplished by tracing RGCs in one retina after intravitreal injection of different tracers in the other eye. In mammals, rabbit and rat, ret-ret RGCs are scarce and more abundant in newborn than in adult animals. To our knowledge, ret-ret RGCs have not been studied in mice. Here we purpose to revisit the presence of ret-ret RGCs in juvenile and young adult rats and mice by using retrograde tracers applied to the contralateral optic nerve instead of intravitreally. In P20 (juvenile) and P60 (young adult) animals, the left optic nerve was intraorbitally transected and Fluorogold (rats) or its analogue OHSt (mice) were applied onto its distal stump. P20 animals were sacrificed 3 (mice) or 5 (rats) days later and adult animals at 5 (mice) or 7 (rats) days. Right retinas were dissected as flat-mounts and double immunodetected for Brn3a and melanopsin. Ret-ret RGCs were those with tracer accumulation in their somas. Out of them some expressed Brn3a and/or melanopsin, while other were negative for both markers. In young adult rats, we found 2 ret-ret RGCs displaced to the inner nuclear layer. In both species, ret-ret RGCs are quite scarce and found predominantly in the nasal retina. In juvenile animals there are significantly more ret-ret RGCs (9 ± 3, rats, 13 ± 3 mice) than in young adult ones (5 ± 6 rats, 7 ± 3 mice). Finally, juvenile and young adult mice have more ret-ret RGCs than rats.

Double labelling of human umbilical cord mesenchymal stem cells with Gd-DTPA and PKH26 and the influence on biological characteristics of hUCMSCs

The aim of this study was to determine whether double labelling of human umbilical cord mesenchymal stem cells (hUCMSCs) with gadolinium-diethylene triamine penta-acetic acid (Gd-DTPA) and PKH26 influences their biological characteristics. A tissue adherence technique was used to separate and purify the hUCMSCs and flow cytometry was performed to detect the surface markers expressed on them. Gd-DTPA and PKH26 were used to label the stem cells and MRI and fluorescence microscopy were used to detect the double-labelled hUCMSCs. A MTT assay was used to delineate the growth curve. Transmission electron microscopy (TEM) and atomic force microscopy were used to demonstrate the ultrastructural features of the hUCMSCs. Flow cytometry showed that hUCMSCs highly expressed CD29, CD90, CD44 and CD105. No expression of CD31, CD34 and CD45 was detected. Very low expression of HLA-DR and CD40 was detected. Atomic force microscopy showed these cells were long, spindle shaped, and the cytoplasm and nucleus had clear boundaries. After double labelling, TEM showed Gd particles aggregated in the cytoplasm in a cluster pattern. The proliferation activity, cell cycle, apoptosis and differentiation of the stem cells were not influenced by double labelling. Thus a tissue adherence technique is helpful to separate and purify hUCMSCs effectively; and Gd-DTPA and PKH26 are promising tracers in the investigation of migration and distribution of hUCMSCs in vivo.

Measuring abutment convergence angles using stereovision dental image processing system

PURPOSE

The purpose of this study was to develop a dental image processing system using a three-dimensional (3D) camera and stereovision technology. The reliability of the system for measuring axial wall convergence angles was evaluated.

MATERIALS AND METHODS

The new system predicted 3D coordinate points from 2D images and calculated distances and angles between points. Two examiners measured axial wall convergence angles for seven artificial abutments using a traditional tracing-based method (TBM) and the stereovision-based method (SVBM). Five wax abutment models of simplified abutment forms were made and axial wall convergence angles of wax models were measured by both methods. The data were statistically analyzed at the level of significance, 0.05.

RESULTS

Intraclass correlation coefficients showed excellent intra-examiner and inter-examiner reliabilities for both methods. Bland-Altman plots and paired t-tests showed significant differences between measurements and true values using TBM; differences were not significant with SVBM.

CONCLUSION

This study found that the SVBM reflected true angle values more accurately than a TMB and illustrated an example of 3D computer science applied to clinical dentistry.

BH-CIFOL: Case-Intensional First Order Logic: (II) Branching Histories

This paper follows Part I of our essay on case-intensional first-order logic (CIFOL; Belnap and Müller (2013)). We introduce a framework of branching histories to take account of indeterminism. Our system BH-CIFOL adds structure to the cases, which in Part I formed just a set: a case in BH-CIFOL is a moment/history pair, specifying both an element of a partial ordering of moments and one of the total courses of events (extending all the way into the future) that that moment is part of. This framework allows us to define the familiar Ockhamist temporal/modal connectives, most notably for past, future, and settledness. The novelty of our framework becomes visible in our discussion of substances in branching histories, i.e., in its first-order part. That discussion shows how the basic idea of tracing an individual thing from case to case via an absolute property is applicable in a branching histories framework. We stress the importance of keeping apart extensionality and moment-definiteness, and give a formal account of how the specification of natural sortals and natural qualities turns out to be a coordination task in BH-CIFOL. We also provide a detailed answer to Lewis's well-known argument against branching histories, exposing the fallacy in that argument.