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1.
Article in English | MEDLINE | ID: mdl-38858280

ABSTRACT

Colorectal cancer remains a major cause of cancer death and morbidity worldwide. Surgery is a major treatment modality for primary and, increasingly, secondary curative therapy. However, with more patients being diagnosed with early stage and premalignant disease manifesting as large polyps, greater accuracy in diagnostic and therapeutic precision is needed right from the time of first endoscopic encounter. Rapid advancements in the field of artificial intelligence (AI), coupled with widespread availability of near infrared imaging (currently based around indocyanine green (ICG)) can enable colonoscopic tissue classification and prognostic stratification for significant polyps, in a similar manner to contemporary dynamic radiological perfusion imaging but with the advantage of being able to do so directly within interventional procedural time frames. It can provide an explainable method for immediate digital biopsies that could guide or even replace traditional forceps biopsies and provide guidance re margins (both areas where current practice is only approximately 80% accurate prior to definitive excision). Here, we discuss the concept and practice of AI enhanced ICG perfusion analysis for rectal cancer surgery while highlighting recent and essential near-future advancements. These include breakthrough developments in computer vision and time series analysis that allow for real-time quantification and classification of fluorescent perfusion signals of rectal cancer tissue intraoperatively that accurately distinguish between normal, benign, and malignant tissues in situ endoscopically, which are now undergoing international prospective validation (the Horizon Europe CLASSICA study). Next stage advancements may include detailed digital characterisation of small rectal malignancy based on intraoperative assessment of specific intratumoral fluorescent signal pattern. This could include T staging and intratumoral molecular process profiling (e.g. regarding angiogenesis, differentiation, inflammatory component, and tumour to stroma ratio) with the potential to accurately predict the microscopic local response to nonsurgical treatment enabling personalised therapy via decision support tools. Such advancements are also applicable to the next generation fluorophores and imaging agents currently emerging from clinical trials. In addition, by providing an understandable, applicable method for detailed tissue characterisation visually, such technology paves the way for acceptance of other AI methodology during surgery including, potentially, deep learning methods based on whole screen/video detailing.

2.
Colorectal Dis ; 25(12): 2392-2402, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37932915

ABSTRACT

AIM: Treatment pathways for significant rectal polyps differ depending on the underlying pathology, but pre-excision profiling is imperfect. It has been demonstrated that differences in fluorescence perfusion signals following injection of indocyanine green (ICG) can be analysed mathematically and, with the assistance of artificial intelligence (AI), used to classify tumours endoscopically as benign or malignant. This study aims to validate this method of characterization across multiple clinical sites regarding its generalizability, usability and accuracy while developing clinical-grade software to enable it to become a useful method. METHODS: The CLASSICA study is a prospective, unblinded multicentre European observational study aimed to validate the use of AI analysis of ICG fluorescence for intra-operative tissue characterization. Six hundred patients undergoing transanal endoscopic evaluation of significant rectal polyps and tumours will be enrolled in at least five clinical sites across the European Union over a 4-year period. Video recordings will be analysed regarding dynamic fluorescence patterns centrally as software is developed to enable analysis with automatic classification to happen locally. AI-based classification and subsequently guided intervention will be compared with the current standard of care including biopsies, final specimen pathology and patient outcomes. DISCUSSION: CLASSICA will validate the use of AI in the analysis of ICG fluorescence for the purposes of classifying significant rectal polyps and tumours endoscopically. Follow-on studies will compare AI-guided targeted biopsy or, indeed, AI characterization alone with traditional biopsy and AI-guided local excision versus traditional excision with regard to marginal clearance and recurrence.


Subject(s)
Polyps , Rectal Neoplasms , Humans , Artificial Intelligence , Biopsy , Indocyanine Green , Prospective Studies , Rectal Neoplasms/surgery , Rectal Neoplasms/pathology
3.
Public Health ; 219: 22-30, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37087859

ABSTRACT

OBJECTIVE: We analyze the dynamics of the mental well-being of the Chilean population in response to the progress of the vaccination strategy implemented by the government. STUDY DESIGN: This study aims at investigating the possibility of using Google Trends as an instrument for tracking mental well-being of the Chilean population. METHODS: We use the volume of searches for keywords in Google Trends (GT) related to Anguish, Anxiety, Depression, and Stress as a proxy for population well-being. Using event study methods, we analyze social attention reactions to news about the vaccination program. We implement a Difference-in-Difference-in-Differences estimation to estimate changes in population welfare by socio-economic status induced by the progress of inoculation. RESULTS: We show that social attention to mental health problems is sensitive to news about the vaccination program. Moreover, and most importantly, we find that mental well-being responds positively to the percentage of inoculated people. This phenomenon appear to be permanent and affected by socio-economic status, with the wealthier population experiencing greater improvements than the less wealthy. CONCLUSIONS: During the COVID-19 vaccination program in Chile, social attention to mental health problems appears to be sensitive to news about the vaccination program. There is also strong evidence of socio-economic status-induced heterogeneity in population responses to program implementation. The above phenomena appears to be permanent and cannot be attributed to either socio-economic segregation in access to vaccines or to the highly stratified schedule of the vaccination program.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , Chile/epidemiology , Search Engine , COVID-19/epidemiology , COVID-19/prevention & control , Vaccination/psychology
4.
Tech Coloproctol ; 28(1): 15, 2023 12 14.
Article in English | MEDLINE | ID: mdl-38095756

ABSTRACT

BACKGROUND: Postoperative ileus (POI) remains a common phenomenon following loop ileostomy closure. Our aim was to determine whether preoperative physiological stimulation (PPS) of the efferent limb reduced POI incidence. METHODS: A PRISMA-compliant meta-analysis searching PubMed, EMBASE and CENTRAL databases was performed. The last search was carried out on 30 January 2023. All randomized studies comparing PPS versus no stimulation were included. The primary endpoint was POI incidence. Secondary endpoints included the time to first passage of flatus/stool, time to resume oral diet, need for nasogastric tube (NGT) placement postoperatively, length of stay (LOS) and other complications. Random effects models were used to calculate pooled effect size estimates. Trial sequential analyses (TSA) were also performed. RESULTS: Three randomized studies capturing 235 patients (116 PPS, 119 no stimulation) were included. On random effects analysis, PPS was associated with a quicker time to resume oral diet (MD - 1.47 days, 95% CI - 2.75 to - 0.19, p = 0.02), shorter LOS (MD - 1.47 days, 95% CI - 2.47 to - 0.46, p = 0.004) (MD - 1.41 days, 95% CI - 2.32 to - 0.50, p = 0.002, I2 = 56%) and fewer other complications (OR 0.42, 95% CI 0.18 to 1.01, p = 0.05). However, there was no difference in POI incidence (OR 0.35, 95% CI 0.10 to 1.21, p = 0.10), the requirement for NGT placement (OR 0.50, 95% CI 0.21 to 1.20, p = 0.12) or time to first passage of flatus/stool (MD - 0.60 days, 95% CI - 1.95 to 0.76, p = 0.39). TSA revealed imprecise estimates for all outcomes (except LOS) and further studies are warranted to meet the required information threshold. CONCLUSIONS: PPS prior to stoma closure may reduce LOS and postoperative complications albeit without a demonstrable beneficial effect on POI. Further high-powered studies are required to confirm or refute these findings.


Subject(s)
Ileostomy , Ileus , Humans , Ileostomy/adverse effects , Flatulence/complications , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Ileus/etiology
5.
Vasc Med ; 27(4): 323-332, 2022 08.
Article in English | MEDLINE | ID: mdl-35387516

ABSTRACT

BACKGROUND: Peripheral artery disease (PAD) is associated with modifiable atherosclerotic risk factors like hypertension, diabetes, hyperlipidemia, and smoking. However, the effect of risk factor control on outcomes and disparities in achieving control is less well understood. METHODS: All patients in an integrated, regional health system with PAD-related encounters, fee-for-service Medicare, and clinical risk factor control data were identified. Component risk factors were dichotomized into controlled and uncontrolled categories (control defined as low-density lipoprotein < 100 mg/dL, hemoglobin A1c < 7.0%, SBP < 140 mmHg, and current nonsmoker) and composite categories (none, 1, ⩾ 2 uncontrolled RFs) created. The primary outcome was major adverse vascular events (MAVE, a composite of all-cause mortality, myocardial infarction, stroke, and lower-extremity revascularization and amputation). RESULTS: The cohort included 781 patients with PAD, average age 72.5 ± 9.8 years, of whom 30.1% were Black, and 19.1% were Medicaid dual-enrolled. In this cohort, 260 (33.3%) had no uncontrolled risk factors and 200 (25.6%) had two or more uncontrolled risk factors. Patients with the poorest risk factor control were more likely to be Black (p < 0.001), Medicaid dual-enrolled (p < 0.001), and have chronic limb-threatening ischemia (p = 0.009). Significant differences in MAVE by degree of risk factor control were observed at 30 days (none uncontrolled: 5.8%, 1 uncontrolled: 11.5%, ⩾ 2 uncontrolled: 13.6%; p = 0.01) but not at 1 year (p = 0.08). risk factor control was not associated with outcomes at 1 year after adjustment for patient and PAD-specific characteristics. CONCLUSIONS: risk factor control is poor among patients with PAD. Significant disparities in achieving optimal risk factor control represent a potential target for reducing inequities in outcomes.


Subject(s)
Medicare , Peripheral Arterial Disease , Aged , Aged, 80 and over , Amputation, Surgical , Humans , Lower Extremity/blood supply , Middle Aged , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/therapy , Risk Factors , Treatment Outcome , United States/epidemiology
6.
Am Heart J ; 239: 135-146, 2021 09.
Article in English | MEDLINE | ID: mdl-34052213

ABSTRACT

BACKGROUND: PAD increases the risk of cardiovascular mortality and limb loss, and disparities in treatment and outcomes have been described. However, the association of patient-specific characteristics with variation in outcomes is less well known. METHODS: Patients with PAD from Duke University Health System (DUHS) between January 1, 2015 and March 31, 2016 were identified. PAD status was confirmed through ground truth adjudication and predictive modeling using diagnosis codes, procedure codes, and other administrative data. Symptom severity, lower extremity imaging, and ankle-brachial index (ABI) were manually abstracted from the electronic health record (EHR). Data was linked to Centers for Medicare and Medicaid Services data to provide longitudinal follow up. Primary outcome was major adverse vascular events (MAVE), a composite of all-cause mortality, myocardial infarction (MI), stroke, lower extremity revascularization and amputation. RESULTS: Of 1,768 patients with PAD, 31.6% were asymptomatic, 41.2% had intermittent claudication (IC), and 27.3% had chronic limb-threatening ischemia (CLTI). At 1 year, patients with CLTI had higher rates of MAVE compared with asymptomatic or IC patients. CLTI and Medicaid dual eligibility were independent predictors of mortality. CLTI and Black race were associated with amputation. CONCLUSIONS: Rates of MAVE were highest in patients with CLTI, but patients with IC or asymptomatic disease also had high rates of adverse events. Black and Medicaid dual-eligible patients were disproportionately present in the CLTI subgroup and were at higher risk of amputation and mortality, respectively. Future studies must focus on early identification of high-risk patient groups to improve outcomes in patients with PAD.


Subject(s)
Amputation, Surgical/statistics & numerical data , Healthcare Disparities/organization & administration , Lower Extremity , Myocardial Infarction/epidemiology , Peripheral Arterial Disease , Stroke/epidemiology , Vascular Surgical Procedures , Asymptomatic Diseases/epidemiology , Black People/statistics & numerical data , Female , Health Services Needs and Demand , Humans , Lower Extremity/blood supply , Lower Extremity/surgery , Male , Medicaid/statistics & numerical data , Middle Aged , Mortality , Peripheral Arterial Disease/complications , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/physiopathology , Risk Factors , United States/epidemiology , Vascular Surgical Procedures/methods , Vascular Surgical Procedures/statistics & numerical data
7.
J Card Fail ; 27(8): 826-836, 2021 08.
Article in English | MEDLINE | ID: mdl-34364659

ABSTRACT

BACKGROUND: We investigated associations between timing of sacubitril/valsartan initiation and postdischarge adherence among patients hospitalized for heart failure with reduced ejection fraction (HFrEF). Clinical trials support initiation of sacubitril/valsartan among patients hospitalized with HFrEF. The association between timing of initiation and postdischarge adherence is unknown. METHODS AND RESULTS: We analyzed patients hospitalized for HFrEF (EF of ≤40%) within the Get With The Guidelines Heart Failure registry linked with Medicare claims between October 2015 and September 2017 who were eligible for sacubitril/valsartan. Follow-up was through December 2018. Patients were grouped by timing of sacubitril/valsartan initiation. Sacubitril/valsartan adherence at 90 and 365 days after discharge was assessed by calculating proportion of days covered (PDC) using medication fills. Among 4666 patients, 108 (2.3%) were continued on sacubitril/valsartan (on sacubitril/valsartan at admission and discharge), 191 (4.1%) were initiated as inpatients, 130 (2.8%) were initiated at discharge, and 4237 (90.1%) were discharged without sacubitril/valsartan. Median (25th, 75th) proportion of days covered through 90 days among those continued, initiated as inpatients, and initiated at discharge was 0.9 (0.6-0.1), 0.3 (0.0-0.7), and 0.0 (0.0-0.7), respectively (P < .001). Patients discharged without sacubitril/valsartan had very low rates of any sacubitril/valsartan fills within 90 and 365 days of discharge (2.1% and 7.7% of surviving patients, respectively). CONCLUSIONS: In 2015-2017 US clinical practice, more than 90% of eligible patients hospitalized for HFrEF were discharged without sacubitril/valsartan. Patients initiated as inpatients had a higher postdischarge proportion of days covered than patients initiated at discharge. Patients discharged without sacubitril/valsartan were unlikely to receive it during follow-up. These findings highlight the importance of initiating sacubitril/valsartan during hospitalization to improve the quality of care.


Subject(s)
Heart Failure , Patient Discharge , Aftercare , Aged , Aminobutyrates/therapeutic use , Angiotensin Receptor Antagonists/therapeutic use , Biphenyl Compounds , Drug Combinations , Heart Failure/drug therapy , Heart Failure/epidemiology , Humans , Medicare , Stroke Volume , Tetrazoles/therapeutic use , United States/epidemiology , Valsartan
8.
Br J Surg ; 108(9): 1022-1025, 2021 Sep 27.
Article in English | MEDLINE | ID: mdl-33829231

ABSTRACT

Laparoscopic surgery has been undermined throughout the COVID-19 pandemic by concerns that it may generate an infectious risk to the operating team through aerosolization of peritoneal particles. There is anyway a need for increased awareness and understanding of the occupational hazard for surgical teams regarding unfiltered escape of pollutants generated by surgical smoke and other microbials. Here, the aerosol-generating nature of this access modality was confirmed through repeatable real-time methodology both qualitatively and quantitively to inform best practice and additional engineering solutions to optimize the operating room environment.


Laparoscopic surgery has been undermined throughout the COVID-19 pandemic by concerns that it may generate an infectious risk to the operating team through aerosolization of peritoneal particles. There is anyway a need for increased awareness and understanding of the occupational hazard for surgical teams regarding unfiltered escape of pollutants generated by surgical smoke and other microbials. Here, the aerosol-generating nature of this access modality was confirmed through repeatable real-time methodology both qualitatively and quantitively to inform best practice and additional engineering solutions to optimize the operating room environment.


Subject(s)
Air Pollutants, Occupational/analysis , Air Pollution, Indoor/analysis , Infection Control/methods , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Laparoscopy/methods , Ventilation , Aerosols , Air Pollutants, Occupational/adverse effects , Air Pollution, Indoor/adverse effects , Air Pollution, Indoor/prevention & control , Humans , Infection Control/instrumentation , Laparoscopy/instrumentation , Operating Rooms , Smoke/analysis
9.
J Dairy Sci ; 104(5): 6124-6133, 2021 May.
Article in English | MEDLINE | ID: mdl-33663823

ABSTRACT

Feeding calves a high-quality and antibody-rich colostrum is an important management practice for supporting calf health and productivity. Colostrum quality and antibody concentrations are highly variable between cows and among quarters within a cow. Intramammary infections often occur during the time of colostrum formation; however, it is unknown if these infections ultimately affect colostrum quality and antibody concentrations. The objective of this study was to determine if antibody concentrations and Brix percentage in colostrum from infected mammary glands (quarters) differed from uninfected. In 2 cross-sectional studies, colostrum samples were aseptically collected at first milking from 110 Holstein and 89 Jersey cows at 3 Holstein and 4 Jersey commercial dairy farms in Ohio. A total of 771 quarter samples were collected, underwent bacteriological culture, and were measured for Brix percentage with a digital refractometer. When 1 infected and 1 uninfected quarter existed among the fore or rear quarters within a cow, IgG1, IgG2, IgA, and IgM antibody concentrations were determined via ELISA for the paired quarters (n = 82). Overall, for Holstein cows, Brix percentages were greater in multiparous than primiparous cows (30.5 vs. 23.7 ± 2.1 SEM), but an opposite pattern was observed for Jersey cows (24.3 vs. 27.2 ± 1.2 SEM). Uninfected quarters in both Holstein and Jersey multiparous cows had greater Brix percentage than colostrum from infected quarters; this pattern was absent for Holstein and Jersey primiparous cows. For Holstein cows, concentrations of IgG1, IgG2, and IgA were greater in multiparous cows than primiparous cows; quarter-infection status did not significantly influence antibody concentrations. For Jersey samples, antibody concentrations did not differ between primiparous and multiparous cows and were not significantly affected by quarter-infection status. The results of these works indicate that infection status at parturition does not markedly affect colostrum antibody concentrations and quality, and that other factors at the local level of the mammary gland more greatly influence colostrogenesis and antibody transport into the mammary gland during colostrogenesis.


Subject(s)
Colostrum , Parturition , Animals , Cattle , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Ohio , Pregnancy
10.
J Dairy Sci ; 104(5): 6200-6211, 2021 May.
Article in English | MEDLINE | ID: mdl-33663842

ABSTRACT

Mammary blood flow is central to mammary growth, development, and productivity, but the development of the vasculature network is poorly understood. The objective of this study was to determine how the vascular system adapts to mammary growth by inducing different levels of mammary growth and examining 2 regions of mammary parenchymal tissue. Holstein heifer calves (n = 12) received daily injections on the days immediately preceding euthanasia at 82 d of age. Treatments were control (CON), short-term estradiol (STE), and long-term estradiol (LTE). The CON calves received corn oil injections, the STE calves received 9 injections of corn oil followed by 3 injections of estradiol, and the LTE calves received 12 estradiol injections. Mammary tissues were collected from the center and edge parenchymal regions of all right rear mammary glands to quantify the tissue area of various tissue structures, the percentage of proliferating epithelial cells, and the number and form of blood vessels. Results showed that LTE calves had a greater tissue area occupied by epithelium than CON and STE calves, and the epithelial area in CON and STE calves was similar. Edge parenchyma had a greater percentage of proliferating epithelial cells than center parenchyma across all treatment groups. In the edge region, LTE calves had the greatest percentage of proliferating epithelial cells, coinciding with greater epithelial area. The number of blood vessels per unit of tissue area was greater in center than in edge parenchyma; the corresponding vessel surface area per unit of tissue area followed the same pattern. Mammary blood vessel measures were not markedly influenced by estradiol treatment. These results highlight the marked difference in the number and organization of blood vessels in different mammary parenchyma regions but indicate that the effects of estradiol on stimulating mammary epithelial proliferation does not directly translate to increasing numbers of blood vessels.


Subject(s)
Estradiol , Mammary Glands, Animal , Animals , Cattle , Cell Count/veterinary , Diet , Epithelial Cells , Estradiol/pharmacology , Estrogens , Female
11.
J Dairy Sci ; 102(9): 8502-8512, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31279552

ABSTRACT

Diet is known to affect rumen growth and development. Calves fed an all-liquid diet have smaller and less developed rumens and a decreased ability to absorb volatile fatty acids (VFA) compared to calves fed both liquid and dry feed. However, it is unknown how rumens respond when challenged with a defined concentration of VFA. The objective of this study was to assess the effects of 2 different feeding programs on VFA absorption in preweaned calves. Neonatal Holstein bull calves were individually housed and randomly assigned to 1 of 2 diets. The diets were milk replacer only (MRO; n = 5) or milk replacer with starter (MRS; n = 6). Diets were isoenergetic (3.87 ± 0.06 Mcal of metabolizable energy per day) and isonitrogenous (0.17 ± 0.003 kg/d of apparent digestible protein). Milk replacer was 22% crude protein, 21.5% fat (dry matter basis). The textured calf starter was 21.5% crude protein (dry matter basis). Feed and ad libitum water intakes were recorded daily. Calves were exposed to a defined concentration of VFA buffer (acetate 143 mM, propionate 100 mM, butyrate 40.5 mM) 6 h before euthanasia on d 43 ± 1. Rumen fluid samples were obtained every 15 to 30 min for 6 h to measure the rate of VFA absorption. Rumen tissues were obtained from the ventral sac region and processed for morphological and immunohistochemical analyses of the VFA transporters monocarboxylate transporter 1 (MCT1) and 4 (MCT4). Body growth did not differ between diets, but empty reticulorumens were heavier in MRS than MRO calves (0.67 vs. 0.39 ± 0.04 kg) and MRS calves had larger papillae areas (0.76 vs. 15 ± 0.08 mm2). We observed no differences between diets in terms of the abundance of MCT1 and MCT4 per unit area. These results indicate that the extrapolated increase in total abundance of MCT1 or MCT4 in MRS calves was not due to increased transporter density per unit area. Modeled VFA absorption metrics (flux, mmol/h, or 6 h absorbed VFA in mmol) were not different across diets. These results demonstrate that the form of calfhood diet, whether solely MR or MR and starter, does not alter VFA absorption capacity when the rumen is exposed to a defined concentration of VFA at 6 wk of age.


Subject(s)
Cattle/metabolism , Diet/veterinary , Fatty Acids, Volatile/metabolism , Rumen/metabolism , Animal Feed/analysis , Animals , Cattle/growth & development , Male , Milk Substitutes , Rumen/growth & development , Weaning
12.
J Dairy Sci ; 102(9): 8486-8501, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31279553

ABSTRACT

Preweaning diet is known to affect rumen tissue appearance at the gross level. The objectives of this experiment were to investigate effects of different preweaning diets on the growth and development of the rumen epithelium and on putative rumen epithelial stem and progenitor cell measurements at the gene and cell levels. Neonatal Holstein bull calves (n = 11) were individually housed and randomly assigned to 1 of 2 diets. The diets were milk replacer only (MRO; n = 5) or milk replacer with starter (MRS; n = 6). Diets were isoenergetic (3.87 ± 0.06 Mcal of metabolizable energy per day) and isonitrogenous (0.17 ± 0.003 kg/d of apparent digestible protein). Milk replacer was 22% crude protein, 21.5% fat (dry matter basis). The textured calf starter was 21.5% crude protein (dry matter basis). Water was available ad libitum and feed and water intake were recorded daily. Putative stem and progenitor cells were labeled by administering a thymidine analog (5-bromo-2'-deoxyuridine, BrdU; 5 mg/kg of body weight in sterile saline) for 5 consecutive days and allowed a 25-d washout period. Calves were killed at 43 ± 1 d after a 6 h exposure to a defined concentration of volatile fatty acids. We obtained rumen tissue from the ventral sac and used it for immunohistochemical analyses of BrdU (putative stem and progenitor cells) and Ki67 (cell proliferation), gene expression analysis, and morphological measurements via hematoxylin and eosin staining. Epithelial stem and progenitor cell gene markers of interest, analyzed by real-time quantitative PCR, were ß1-integrin, keratin-14, notch-1, tumor protein p63, and leucine-rich repeat-containing G protein-coupled receptor 5. Body growth did not differ by diet, but empty reticulorumens were heavier in MRS calves (MRS: 0.67 ± 0.04 kg; MRO: 0.39 ± 0.04 kg). The percentage of label-retaining BrdU basale cells was higher in MRO calves than in MRS calves (2.0 ± 0.3% vs. 0.3 ± 0.2%, respectively). We observed a higher percentage of basale cells undergoing proliferation in MRS calves than in MRO calves (18.4 ± 2.6% vs. 10.8 ± 2.8%, respectively). Rumen epithelial gene expression was not affected by diet, but the submucosa was thicker in MRO calves and the epithelium and corneum/keratin layers were thicker in MRS calves. Presumptive stem and progenitor cells in the rumen epithelium were identifiable by their ability to retain labeled DNA in the long term, changed proliferative status in response to diet, and likely contributed to observed treatment differences in rumen tissue thickness.


Subject(s)
Cattle/growth & development , Diet/veterinary , Rumen/growth & development , Animals , Cattle/physiology , Cell Proliferation , Epithelial Cells/physiology , Male , Rumen/cytology , Stem Cells/physiology , Weaning
13.
Am Heart J ; 200: 134-140, 2018 06.
Article in English | MEDLINE | ID: mdl-29898842

ABSTRACT

BACKGROUND: On May 20, 2016, US professional organizations in cardiology published joint treatment guidelines recommending the use of angiotensin-receptor neprilysin inhibitor (ARNI) for eligible patients with heart failure with reduced ejection fraction (HFrEF). Using data from the Get With The Guidelines-Heart Failure registry, we evaluated the early impact of this update on temporal trends in ARNI prescription. METHODS: We analyzed patients with HFrEF who were eligible for ARNI prescription (EF ≤40%, no contraindications) and hospitalized from February 20, 2016, through August 19, 2016-allowing for 13weeks before and after guideline publication. We quantified trends in ARNI use associated with guidelines publication with an interrupted time-series design using logistic regression and accounting for correlations within hospitals using general estimating equation methods. RESULTS: Of 7,200 eligible patient hospitalizations, 51.9% were discharged in the period directly preceding publication of the guidelines, and 48.1% were discharged after. Odds ratios of ARNI prescription at discharge were significantly higher in the postguideline period compared with the preguideline period in adjusted models (adjusted odds ratio 1.29, 95% CI 1.06-1.57, P=.01). However, there was no significant interaction between observed and expected ARNI use after guideline publication (Pinteraction=.14). Results were consistent using a 6-month before and after time frame. CONCLUSIONS: The model suggested a small increase in ARNI use in HF patients being discharged from the hospital immediately after guideline release. However, the publication of national guidelines recommending ARNI use seemed to have little influence on the adoption of this evidence-based medication in the first 3 to 6months.


Subject(s)
Angiotensin Receptor Antagonists/therapeutic use , Heart Failure/drug therapy , Practice Guidelines as Topic , Practice Patterns, Physicians'/statistics & numerical data , Publishing , Aged , Female , Heart Failure/diagnosis , Heart Failure/epidemiology , Heart Failure/metabolism , Humans , Information Dissemination/methods , Male , Neprilysin/antagonists & inhibitors , Patient Selection , Stroke Volume/drug effects , Surveys and Questionnaires , Time Factors , United States
14.
Neural Comput ; 30(2): 378-396, 2018 02.
Article in English | MEDLINE | ID: mdl-29162002

ABSTRACT

Brain activity evolves through time, creating trajectories of activity that underlie sensorimotor processing, behavior, and learning and memory. Therefore, understanding the temporal nature of neural dynamics is essential to understanding brain function and behavior. In vivo studies have demonstrated that sequential transient activation of neurons can encode time. However, it remains unclear whether these patterns emerge from feedforward network architectures or from recurrent networks and, furthermore, what role network structure plays in timing. We address these issues using a recurrent neural network (RNN) model with distinct populations of excitatory and inhibitory units. Consistent with experimental data, a single RNN could autonomously produce multiple functionally feedforward trajectories, thus potentially encoding multiple timed motor patterns lasting up to several seconds. Importantly, the model accounted for Weber's law, a hallmark of timing behavior. Analysis of network connectivity revealed that efficiency-a measure of network interconnectedness-decreased as the number of stored trajectories increased. Additionally, the balance of excitation (E) and inhibition (I) shifted toward excitation during each unit's activation time, generating the prediction that observed sequential activity relies on dynamic control of the E/I balance. Our results establish for the first time that the same RNN can generate multiple functionally feedforward patterns of activity as a result of dynamic shifts in the E/I balance imposed by the connectome of the RNN. We conclude that recurrent network architectures account for sequential neural activity, as well as for a fundamental signature of timing behavior: Weber's law.


Subject(s)
Models, Neurological , Neurons/physiology , Animals , Behavior/physiology , Brain/physiology , Neural Inhibition/physiology , Neural Pathways/physiology , Synapses/physiology , Time Factors
15.
J Microsc ; 266(2): 126-140, 2017 05.
Article in English | MEDLINE | ID: mdl-28165142

ABSTRACT

Filamentous fungi have a complex morphology that induces fermentation process development issues, as a consequence of viscosity increase and diffusion limitations. In order to better understand the relationship between viscosity changes and fungus morphology during fermentations of Trichoderma reesei, an accurate image analysis method has been developed to provide quantitative and representative data for morphological analysis. This method consisted of a new algorithm called FACE that allowed sharp images to be created at all positions, segmentation of fungus, and morphological analysis using skeleton and topological approaches. It was applied and validated by characterizing samples of an industrial strain of Trichoderma reesei that had or had not been exposed to an extreme shear stress. This method allowed many morphological characteristics to be identified, among which nine relevant criteria were extracted, regarding the impact of shear stress on the fungus and on the viscosity of the fermentation medium.


Subject(s)
Fungi/cytology , Image Processing, Computer-Assisted/methods , Microscopy/methods , Trichoderma/cytology , Fermentation , Fungi/metabolism , Industrial Microbiology/methods , Trichoderma/metabolism
16.
Am Heart J ; 173: 172-8, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26920611

ABSTRACT

BACKGROUND: Elevated heart rate of ≥70 beats/min despite ß-blocker use may represent a new treatment target in patients in sinus rhythm with heart failure with reduced ejection fraction. However, little is known about the proportion of patients with elevated heart rate despite ß-blocker therapy. METHODS: We analyzed data from a large clinical registry to describe discharge heart rate as a function of ß-blocker use and dose. We included patients with left ventricular ejection fraction <40% who were admitted with acute heart failure in 2003 and 2004; we excluded patients with a history of atrial arrhythmia or with a pacemaker or cardiac resynchronization therapy. We considered the ß-blockers carvedilol, metoprolol succinate, bisoprolol, atenolol, and metoprolol tartrate and described discharge dose as a percentage of target dose (ie, <25%, 25%-49%, 50%-99%, and ≥100%). RESULTS: Among 10,696 patients, median discharge heart rate was 76 beats/min (interquartile range [IQR] 66-86 beats/min). Of these, 7,826 (73%) were discharged on a ß-blocker. For patients not on a ß-blocker, median discharge heart rate was 80 beats/min (IQR 70-89 beats/min), compared with 78 beats/min (IQR 69-88 beats/min) on <25% of target dose, 75 beats/min (IQR 66-85 beats/min) on 25% to 49% of target dose, 74 beats/min (IQR 66-82 beats/min) on 50% to 99% of target dose, and 72 beats/min (IQR 65% to 80%) on 100% of target dose or greater (P < .001). Most patients, 7,647 (71%), had a discharge heart rate of ≥70 beats/min, including 1,460 (63%) of 2,301 patients discharged on 50% of target dose or greater. CONCLUSIONS: Despite treatment with ß-blockers, a substantial proportion of patients hospitalized with heart failure with reduced ejection fraction have elevated heart rate at discharge.


Subject(s)
Adrenergic beta-Antagonists/administration & dosage , Heart Failure/physiopathology , Heart Rate/physiology , Patient Discharge , Registries , Aged , Dose-Response Relationship, Drug , Female , Follow-Up Studies , Heart Failure/drug therapy , Heart Rate/drug effects , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
17.
J Card Fail ; 22(10): 781-8, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26687985

ABSTRACT

BACKGROUND: Heart failure (HF) with preserved ejection fraction (HFpEF) is more common in women than in men; data characterizing sex differences in the management and outcomes of HFpEF patients presenting to the emergency department (ED) are limited. METHODS AND RESULTS: Using Acute Decompensated Heart Failure National Registry Emergency Module data linked to Medicare claims, we conducted a retrospective analysis of acute HF patients in the ED, identifying HFpEF (ejection fraction [EF] ≥40%) patients and stratifying by sex to compare baseline characteristics, ED therapies, hospital length of stay (LOS), in-hospital mortality, and post-discharge outcomes. Of 4161 HFpEF patients, 2808 (67%) were women, who were more likely to be older and hypertensive, but less likely to be diabetic or smokers (all P < .01). Women more often presented with systolic blood pressure >140 mm Hg (62.5% vs 56.4%; P = .0001) and higher EF. There were no sex differences in ED therapies, adjusted 30- and 180-day all-cause mortality, in-hospital mortality, or 30- and 180-day readmissions. After adjustment, women had longer LOS (0.40 days, 95% confidence interval [CI] 0.10-0.70; P = .008). CONCLUSIONS: Women with HFpEF presenting to the ED were more likely to have elevated systolic blood pressure, but overall ED management strategies were similar to those in men. We observed adjusted differences in hospital LOS, but no differences in 30- and 180-day outcomes.


Subject(s)
Heart Failure/diagnostic imaging , Heart Failure/mortality , Hospital Mortality , Stroke Volume/physiology , Acute Disease , Aged , Aged, 80 and over , Cause of Death , Cohort Studies , Emergency Service, Hospital/statistics & numerical data , Female , Heart Failure/therapy , Humans , Kaplan-Meier Estimate , Male , Prognosis , Registries , Retrospective Studies , Risk Assessment , Sex Factors , Survival Analysis , Treatment Outcome
19.
Epidemiology ; 26(6): 815-20, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26133022

ABSTRACT

BACKGROUND: This study describes the availability and characteristics of databases in Asian-Pacific countries and assesses the feasibility of a distributed network approach in the region. METHODS: A web-based survey was conducted among investigators using healthcare databases in the Asia-Pacific countries. Potential survey participants were identified through the Asian Pharmacoepidemiology Network. RESULTS: Investigators from a total of 11 databases participated in the survey. Database sources included four nationwide claims databases from Japan, South Korea, and Taiwan; two nationwide electronic health records from Hong Kong and Singapore; a regional electronic health record from western China; two electronic health records from Thailand; and cancer and stroke registries from Taiwan. CONCLUSIONS: We identified 11 databases with capabilities for distributed network approaches. Many country-specific coding systems and terminologies have been already converted to international coding systems. The harmonization of health expenditure data is a major obstacle for future investigations attempting to evaluate issues related to medical costs.


Subject(s)
Databases, Factual , Electronic Health Records , Information Dissemination/methods , Insurance, Health , Registries , China , Clinical Coding , Computer Communication Networks , Feasibility Studies , Health Expenditures , Hong Kong , Humans , Japan , Neoplasms , Pharmacoepidemiology , Republic of Korea , Singapore , Stroke , Taiwan , Thailand
20.
J Evol Biol ; 28(1): 105-16, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25382409

ABSTRACT

Extraordinarily high rates of recombination have been observed in some eusocial species. The most popular explanation is that increased recombination increases genetic variation among workers, which in turn increases colony performance, for example by increasing parasite resistance. However, support for the generality of higher recombination rates among eusocial organisms remains weak, due to low sample size and a lack of phylogenetic independence of observations. Recombination rate, although difficult to measure directly, is correlated with chromosome number. As predicted, several authors have noted that chromosome numbers are higher among the eusocial species of Hymenoptera (ants, bees and wasps). Here, we present a formal comparative analysis of karyotype data from 1567 species of Hymenoptera. Contrary to earlier studies, we find no evidence for an absolute difference between chromosome number in eusocial and solitary species of Hymenoptera. However, we find support for an increased rate of chromosome number change in eusocial taxa. We show that among eusocial taxa colony size is able to explain some of the variation in chromosome number: intermediate-sized colonies have more chromosomes than those that are either very small or very large. However, we were unable to detect effects of a number of other colony characteristics predicted to affect recombination rate - including colony relatedness and caste number. Taken together, our results support the view that a eusocial lifestyle has led to variable selection pressure for increased recombination rates, but that identifying the factors contributing to this variable selection will require further theoretical and empirical effort.


Subject(s)
Chromosomes, Insect , Hymenoptera/genetics , Recombination, Genetic , Social Behavior , Animals , Biological Evolution , Female , Hymenoptera/physiology , Male , Phylogeny , Phylogeography , Population Density
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