Graduate Student Literature Review: System, plant, and animal factors controlling dietary pasture inclusion and their impact on ration formulation for dairy cows

Diet formulation in a pasture-based dairy system is a challenge as the quality and quantity of available pasture, which generally constitutes the base diet, is constantly changing. The objective of this paper is to cover a more in-depth review of the nutritional characteristics of pasture-based diets, identifying potential system, plant, and animal factors that condition pasture dietary inclusion in dairy cows. In practice, there is a wide diversity of pasture-based systems with predominant to minimal use of pasture requiring a more specific classification that potentially considers the amount and time of access to pasture, access to housing, length of grazing season, seasonality of calving, and level and method of supplementation. There are important differences in the nutritional quality between pasture species and even cultivars. However, under management practices that promote maintenance of pasture in a vegetative state as well as controlling the availability of pasture, it is possible to achieve high dry matter intakes (∼2.9%-3.4% of live weight) of pasture with moderate to high diet energy density, protein supply, and digestibility. The amount of pasture to include in the diet will depend on several factors, such as the type of production system, the cost of supplementary feeds, and the farmer's objectives, but inclusions of ∼40% to 50% of the diet seem to potentially reduce costs while apparently not limiting voluntary feed intake. Considering that there seems to be a continuum of intermediate management systems, a better understanding of the factors inherent to the feed ingredients used, as well as the use of nutrients by cows, and potential interactions between animal × system should be addressed in greater depth. This requires a meta-analysis approach, but given the diversity of the pasture-based system in practice, the existing information is highly fragmented. A clear definition of "subsystems" is necessary to direct the future research and development of mechanistic models.

Sub-Bandgap Sensitization of Perovskite Semiconductors via Colloidal Quantum Dots Incorporation

By taking advantage of the outstanding intrinsic optoelectronic properties of perovskite-based photovoltaic materials, together with the strong near-infrared (NIR) absorption and electronic confinement in PbS quantum dots (QDs), sub-bandgap photocurrent generation is possible, opening the way for solar cell efficiencies surpassing the classical limits. The present study shows an effective methodology for the inclusion of high densities of colloidal PbS QDs in a MAPbI3 (methylammonium lead iodide) perovskite matrix as a means to enhance the spectral window of photon absorption of the perovskite host film and allow photocurrent production below its bandgap. The QDs were introduced in the perovskite matrix in different sizes and concentrations to study the formation of quantum-confined levels within the host bandgap and the potential formation of a delocalized intermediate mini-band (IB). Pronounced sub-bandgap (in NIR) absorption was optically confirmed with the introduction of QDs in the perovskite. The consequent photocurrent generation was demonstrated via photoconductivity measurements, which indicated IB establishment in the films. Despite verifying the reduced crystallinity of the MAPbI3 matrix with a higher concentration and size of the embedded QDs, the nanostructured films showed pronounced enhancement (above 10-fold) in NIR absorption and consequent photocurrent generation at photon energies below the perovskite bandgap.

Evaluation of walking activity data during pregnancy as an indicator of pregnancy loss in dairy cattle

A pregnancy loss or abortion can be assumed when a dairy cow that has been previously diagnosed pregnant shows signs of estrus. In herds using leg-based pedometers as a tool to detect cows in estrus, a sudden increase in walking activity (hereafter, activity peaks) relative to a certain threshold activity triggers an estrous alert that can be confused with a pregnancy loss. The objective of this study was to determine whether pregnant cows can show activity peaks as measured by pedometers. We used data from a dairy herd of 250 milking cows using pedometers as a means of measuring walking activity to detect cows in estrus. Two databases were used in this study, which included the walking activity of the entire herd recorded by the pedometers from January 1, 2018, to December 31, 2021 (database 1), and the calving dates, the insemination dates, the dates when a pregnancy diagnosis was declared pregnant, the dates when a pregnancy diagnosis was declared not pregnant or open, and the abortion dates (database 2). Activity peaks were identified within an experimental unit, which was defined as pregnant cows showing an insemination event followed by a confirmed pregnancy and subsequent calving. The activity peaks were identified using the peak searching algorithm that compares the step count on a given day with the step counts of its adjacent days. The candidate peaks were characterized for their magnitudes by the prominence metric. A chi-squared test was performed to test the specificity of the system. From the 4-yr database, 537 pregnancies or experimental units were identified, and 77 pregnancies showed 1 or more peaks, which means that 14.4% of the pregnancies showed activity peaks. Within the pregnancies showing peaks (n = 77), the median equaled 1 peak/pregnancy, the average equaled 1.53 peaks/pregnancy, and the maximum equaled 13 peaks/pregnancy. In conclusion, activity peaks can be observed for pregnant cows using pedometers. These peaks could generate false estrous alerts during the pregnancy period when using pedometers, and these false alerts should not be interpreted as pregnancy losses.

The HFFI, a new frailty index for assessing long-term outcomes in heart failure

Introduction

Patients hospitalized due to heart failure (HF) compose a heterogeneous population whose prognosis is difficult to forecast. Frailty is a well-recognized prognostic marker in multiple chronic diseases, including HF; however, frailty evaluation is often subjective and standardized and objective prediction models are lacking. We aimed to evaluate if an objective and simple index – Heart Failure Frailty Index (HFFI)– can predict long-term outcomes in this population.

Methods

A retrospective analysis of 258 patients admitted to a Cardiology ward due to HF was performed. The variables albumin, C-reactive protein levels, age and body mass index (BMI) were selected for frailty assessment. After attributing points for each variable, according to odds ratio on univariate analysis, the HFFI was calculated (range 0–8), resulting from the sum of the points attributed to each variable. Kaplan-Meyer and Cox-regression analysis were performed to evaluate HFFI association with 24-month mortality (24MM) and 24-month composite endpoint of rehospitalization or death (24MH).

Results

Mean patient age was 75 (±11) years; 51% were men. 45.7% had atrial fibrillation, 15.9% hat history of acute myocardial infarction, 67.8% had hypertension. Mean LVEF was 47% (±17). A LVEF <40% was present in 40% of patients. 24MM was 11.5% and 24 MH was 58%. Patients were considered frail if they had an HFFI ≥3. Kaplan-Meyer curve analysis revealed a significantly lower median time to 24MM in frail patients, as assessed by HFFI, comparing to non-frail patients (585±33 days vs 697±12 days, mortality rate: 25.4% vs 5.7%, χ2=18.156, p<0.001). There was also a significantly lower median time to 24MH in frail patients (336±34 days vs 449±24 days, combined endpoint rate: 76.1% vs 50.3%, χ2=10.884, p=0.001). Cox regression analysis demonstrated that HFFI independently predicts 24MM (HR: 1.364, p=0.002) and 24MH (HR: 1.106, p=0.035), even after adjustment for other prognostic markers, such as history of atrial fibrillation, previous myocardial infarction, diabetes and natriuretic peptides serum level at index event.

Conclusion

HFFI is a simple and objective frailty index correlated with 24MM and 24MH, being an independent prognostic marker in this population. Its use may help to identify patients with a high risk of mortality or readmission, in need of specialized care.

Funding Acknowledgement

Type of funding sources: None.

Artificial intelligence as a precision tool for predicting risk of in-hospital death after aortic valve replacement

Background/Introduction

The prediction of risk of in-hospital death associated with cardiac surgery still has important gaps. In this scenario, the computational tools and mathematical techniques, the pillars of artificial intelligence, can represent an effective solution to this problem.

Purpose

To develop an in-hospital death prediction model for isolated aortic valve replacement (AVR) based on an artificial intelligence constituted by an artificial neural network (ANN).

Methods

352 patients consecutively submitted to isolated AVR between 2010 and 2020 were included. Altogether, 30 baseline variables were evaluated. Initially, the Extra Tree Classifier machine learning algorithm was used to select the attributes with the highest association with death. With the application of the algorithm, it was possible to identify the 11 variables with the greatest weight associated with in-hospital death. After selecting the variables and dividing the dataset into training (70%) and testing (30%), a risk prediction model was structured through an ANN with multiple layers. The ReLU activation function was used in the hidden layers and the SoftMax activation function was used in the output layer. As an optimizing function of the ANN, the Nadam function was used. In addition, a thousand cycles of propagation and data return (Epochs) were performed to induce machine learning based on the cyclic adjustment of the weights of each of the independent variables included in the model. Accuracy assessments were performed using the ROC curve in the test dataset. The model was developed using the Python programming language.

Results

A predictive accuracy of 93,6% (AUC 0,936) was observed for the occurrence of in-hospital death in the test dataset to the ANN. When comparing the performance of traditional risk scores, also tested only in the test dataset, we found that the ANN-based model was significantly superior to the scores (EuroScore I = 84,0% (AUC 0,840); EuroScore II = 84,4% (AUC 0,844), STS Score = 74,0% (AUC 0,740). The area under the curve of the model based on the ANN was significantly higher when compared to the areas of the scores using the DeLong test (p<0.05). When applying the same model only to patients aged 75 and over, the results were as follows: ANN AUC 0,877; ES1 AUC 0,652; ES2 AUC 0,590; STS AUC 0,663 (p<0,05).

Conclusion

The application of artificial intelligence modelling is feasible for the creation of prediction models in the health area. In this study, the accuracy of the ANN was significantly higher than that of the other traditional risk scores in the general sample and for patients with more advanced age. These findings demonstrate the great potential that representative datasets have when accessed through artificial intelligence techniques. The demand for massive volumes of information is mitigated when well-structured datasets with extreme data quality is used.

Funding Acknowledgement

Type of funding sources: None.

Artificial intelligence as a precision tool for predicting risk of in-hospital death after coronary artery bypass graft surgery

Background/Introduction

The prediction of risk of in-hospital death associated with cardiac surgery still has important gaps. In this scenario, the computational tools and mathematical techniques that constitute data science and provide machine learning, pillars of artificial intelligence, can represent an effective solution to this problem.

Purpose

To develop an in-hospital death prediction model for isolated CABG based on an artificial intelligence constituted by an artificial neural network (ANN).

Methods

3,124 patients consecutively submitted to isolated CABG between 2010 and 2020 were included. Altogether, 30 baseline and operative variables were evaluated. Initially, the Extra Tree Classifier machine learning algorithm was used to select the attributes with the highest association with death. With the application of the algorithm, it was possible to identify the 13 variables with the greatest weight associated with hospital death. After selecting the variables and dividing the dataset into training (70%) and testing (30%), a risk prediction model was structured through an ANN with multiple layers. The ReLU activation function was used in the hidden layers and the SoftMax activation function was used in the output layer to extract the specific probability of death and survival. As an optimizing function of the ANN, the Nadam function was used. In addition, a thousand cycles of propagation and data return (Epochs) were performed to induce machine learning based on the cyclic adjustment of the weights of each of the independent variables included in the model. Accuracy assessments were performed using the ROC curve in the test dataset. The model was developed using the Python programming language.

Results

After consolidating machine learning based on the training dataset with 70% of the general sample, it was possible to observe that through the artificial intelligence technique, a predictive accuracy of 83.86% (AUC 0.8386) was obtained for the occurrence of in-hospital death in the test dataset. When comparing the performance of traditional risk scores, also tested only in the test dataset, we found that the ANN-based model was significantly superior to the scores (EuroScore I = 71.4% (AUC 0.714); EuroScore II = 71.9% (AUC 0.719), STS Score = 71.1% (AUC 0.714). The area under the curve of the model based on the ANN was significantly higher when compared to the areas of the scores using the DeLong test (p<0.05)

Conclusion

The application of artificial intelligence modelling is feasible for the creation of prediction models in the health area. In this study, the accuracy of the ANN was significantly higher than that of the other traditional risk scores. These findings demonstrate the great potential that representative datasets have when accessed through artificial intelligence techniques. The demand for massive volumes of information is mitigated when well-structured datasets with extreme data quality is used.

Funding Acknowledgement

Type of funding sources: None.

Impact of atrial fibrillation on in-hospital outcomes of coronary artery bypass graft surgery: an analysis by propensity score matching

Background/Introduction

Many patients referred for coronary artery bypass graft (CABG) surgery have persistent or permanent atrial fibrillation (AF). Despite the significant occurrence, the impact of this arrythmia on surgical outcomes remains uncertain.

Purpose

To assess the impact of persistent or permanent AF on post-CABG in-hospital outcomes.

Methods

A cohort of 3,124 patients undergoing to isolated CABG between 2010 and 2020 was evaluated. A propensity score pairing was applied, considering persistent or permanent AF as a dependent variable and another 19 baseline characteristics as independent variables in the regression model used to build the propensity score. Pairing was performed at a ratio of 3:1 – Group 1: 324 patients without persistent or permanent AF; Group 2: 108 patients with the documented diagnosis of persistent or permanent AF. The statistical plan also included normality analyses, descriptive and univariate analyses, binary logistic regression, ROC curves and DeLong test to compare de curves. The significance level adopted was 5%. The analyses were performed by the programming language Python.

Results

None of the baseline characteristics evaluated showed a significant difference between the groups, including the EuroScore II (Group 1: 1.54±1.45 vs Group 2: 1.49±1.59; p=0.990). Likewise, none of the analysed surgical characteristics showed a significant difference, indicating a very approximate pattern of complexity of the surgeries. The absence of differences demonstrated a high degree of homogeneity between the groups. The use of pairing by propensity score aimed to form two extremely similar study groups, which differed only in relation to the diagnosis of the arrhythmia under study. Among the outcomes evaluated, AMI (1.5 vs 6.5; p=0.013), MACCE (7.1% vs 14.8%; p=0.015) and death (1.5% vs 6.5%; p=0.013) had significantly higher incidences in Group 2, formed by patients with persistent or permanent AF. From the multivariate analysis, it can be identified that permanent AF was an independent risk predictor for the occurrence of in-hospital death (OR: 5.009; 95% CI 1.433–17.507; p=0.012). Finally, it was also possible to verify that the association of EuroScore II with persistent or permanent AF showed higher predictive accuracy than EuroScore II alone (ESII+FA = AUC 0.852 vs ESII alone = AUC 0.775, p<0,05).

Conclusion(s)

Patients with persistent or permanent AF had significantly higher incidences of AMI, MACCE and in-hospital death. Persistent or permanent AF was characterized as an independent predictor for the occurrence of death and the association with the EuroScore II resulted in a 9.9% increase in the predictive accuracy of the surgical risk score.

Funding Acknowledgement

Type of funding sources: None.

POS1285 IMMUNOGENICITY AND SAFETY OF THE CHADOX 1 COVID-19 VACCINE IN PATIENTS WITH AUTOIMMUNE DISEASES AND HEALTHY CONTROLS: DATA FROM SAFER STUDY

Background

Patients with autoimmune inflammatory diseases (AID) have been prioritized for urgent vaccination to mitigate COVID-19 risk. However, few studies in the literature assessed the immunogenicity and safety of the COVID-19 vaccine in patients with AID.

Objectives

In this context, the present study aims to evaluate the immunogenicity and safety of the vaccine against COVID-19 in patients with AID.

Methods

These data are from “Safety and efficacy on COVID-19 Vaccine in Rheumatic Disease” - SAFER study, a Brazilian multicentric prospective phase IV study to evaluate COVID-19 Vaccine in AID, in the real-life, in Brazil. Immunogenicity and adverse events (AE) from a single center were assessed, after 2 doses of ChAdOx1 (Oxford/AstraZeneca), 8 weeks of interval, in patients with AID and healthy controls (HC). Inclusion criteria were age ≥ 18 years and fulfilling criteria according to international classification for AID. Exclusion criteria: pregnancy, previous severe AE to any vaccine, other immunosuppression causes. Stratification of post-vaccination AE was performed using a diary, filled out daily and returned at the end of 28 days for each dose. Participants were followed up through blood collection for measurement of IgG antibodies against SARS-CoV-2 spike receptor-binding domain by chemiluminescence (SARS-CoV-2 IgG II Quant assay, Abbott Laboratories, Abbott Park, IL, USA) at baseline and 28 days after the second dose. The seropositivity was defined for titers ≥50 AU/mL. Quantitative analyses were presented as observed frequency, percentage, central tendency, and variability measurements. The sample’s normal distribution was verified through the Shapiro-Wilk test. The Kruskal-Wallis test and the post-hoc Dwass-Steel-Critchlow-Fligner pairwise comparisons test were used to compare the IgG-S titers between the groups through the evaluation period. Categorical data were addressed using the Fisher´s exact or Chi-squared (χ2) test. An alpha level of 5% significance was used in all analyses.

Results

A total of 377 volunteers with AID and 50 HC were included in the study. Patients with spondyloarthritis (N=64), systemic lupus erythematosus (N=63), rheumatoid arthritis (N=61), primary Sjögren’s syndrome (N=61), vasculitis (N=31), systemic sclerosis (N=14), inflammatory myopathy (N=9), Crohn´s disease (N=49), ulcerative colitis (N=11) and other systemics AID (N=12) were evaluated. Both groups had female predominance (73.5% vs. 74.0%, p=0.937) and were homogeneous for age (43.5 vs. 41.7,p=0.308). The seroconversion among those not reactive (IgG-S negative at baseline) (46 HC and 191 AID), 28 days after second dose was 97.1% for spondyloarthritis (p=0.425), systemic lupus erythematosus 88.2% (0.006), rheumatoid arthritis 93.5% (0.158), primary Sjögren’s syndrome 92.6% (0.133), systemic sclerosis or inflammatory myopathy 47.1% (0.001), inflammatory bowel disease 100% (0.999) and vasculitis 80% (0.006), while in healthy control was 100%. In comparison with HC, there was a statistically significant difference in IgG-S titles only in systemic sclerosis or inflammatory myopathy (1.694 AU/ml vs. 3.719 AU/ml; p=0.006). Both groups only presented mild AE. Pain at the injection (85.7% vs. 78.4%, p=0.239), headache (67.3% vs. 53.8, p=0.074) and fatigue (59.2% Vs. 46.2%, p=0.089) were more common in HC than AID. Overall, reactions like arthralgia (52.6 vs. 22.4%, p<0.001), hematoma (14.1 vs. 4.1%, p=0.05), cutaneous rash (9.5 vs. 0%, p=0.024) were more frequent in AID. Most participants related that they felt safer after receiving a COVID-19 vaccination, and 52.4% did not reported a worse patient global assessment (PGA) index.

Conclusion

In conclusion, our data indicated that ChAdOx1 vaccine is safe and induced high titers and seroconversion rate in AID. More severe AID, such as vasculitis, systemic lupus erythematosous, and systemic sclerosis and myositis showed a lower seroconversion rate. Further analysis will explore the association between immunossupressant and reactivity, and booster dose.

Acknowledgements

Acknowledgements to DECIT/MS and ICEPI/SESA for supporting the study.

Disclosure of Interests

None declared

Somatic homozygous loss of SH2B3, and a non-Robertsonian translocation t(15;21)(q25.3;q22.1) with NTRK3 rearrangement, in an adolescent with progenitor B-cell acute lymphoblastic leukemia with the iAMP21

Intrachromosomal amplification of chromosome 21 (iAMP21) occurs in ∼2% of B-cell acute lymphoblastic leukemia (ALL) and is considered to confer a poor prognosis. The relapse risk is associated with therapy intensity, suggesting that other somatic mutations may influence iAMP21-ALL prognosis. This abnormality is characterized by multiple copies of the RUNX1 gene in chromosome 21 and appears to arise through multiple breakage-fusion bridge cycles and chromothripsis. Rob(15;21) or a ring chromosome 21 have been associated with an increased risk for iAMP21-ALL, suggesting that constitutional genetic abnormalities may also drive leukemogenesis. Here we describe homozygous deletion of the SH2B3 gene, chromothripsis of chromosome 21, and a non-Robertsonian somatic t(15;21)(q25.3;q22.1) with NTRK3 gene rearrangement in an adolescent with iAMP21-B-ALL. Molecular cytogenetic studies detected iAMP21 with aCGH analysis revealing further genomic imbalances. The RT-qPCR analysis detected elevated expression levels of RUNX1 (68-fold) and reduced expression of CDK6 (0.057-fold). Studies with constitutive cells collected from mouth swabs showed that SH2B3 biallelic deletion was a somatic alteration occurring during clonal evolution. The identification of novel secondary genetic changes was valuable to discuss sporadic iAMP21 leukemogenic mechanisms. For the first time, we show a t(15;21)(q25.3;q22.1) with NTRK3 rearrangement in an adolescent with iAMP21-ALL.

A new ratio with PaO2/FiO2 and pulmonary arterial systolic pressure in the prognosis of intermediate high risk pulmonary embolism

Background

Intermediate high (IH) risk pulmonary embolism (PE) defines a category of patients (P) at increased risk of haemodynamic decompensation. Therefore, it is important to develop tools to identify P who will have an unfavourable outcome. The ratio between arterial oxygen partial pressure (PaO2) to fractional inspired oxygen (FiO2) – P/F ratio - is associated with in-hospital mortality (IHM) in PE. Pulmonary arterial systolic pressure (PASP) is another prognostic factor, related with right ventricular (RV) pressure overload. This study evaluates the usefulness of a new ratio with P/F divided by PASP (P/F:PASP), reflecting both severity of respiratory failure and pressure overload, in the prognosis of P with IH risk PE.

Methods

All P admitted for IH risk PE in an Intensive Cardiac Care Unit (ICCU) for 10 years were included. P/F ratio was calculated with admission blood gas analysis and PASP was obtained with echocardiography at admission in ICCU. P/F:PASP ratio was considered low if inferior to its median. Need for fibrinolysis and IHM were assessed. Follow-up (FU) of 2 years for all-cause mortality was done. Statistical analysis used chi-square and Mann-Whitney U tests, binary logistic regressions and Kaplan-Meier curves.

Results

101 P were studied (mean age 63±17 years; 35.6% male). Mean P/F, PASP and P/F:PSAP were 264±68, 45±15 mmHg and 6.7±3.3, respectively. P/F:PASP was considered low if inferior to 5.9.

There was no difference in age, gender, comorbidities or Pulmonary Embolism Severity Index (PESI) between P with low or high P/F:PASP. However, low P/F:PASP ratio was associated with tachypnea at admission (p=0.034), higher BNP level (p=0.011), right precordial leads T-wave inversion (p=0.029), presence of echocardiographic right ventricle dilation (p=0.002) and lower TAPSE (p=0.002).

Among P who underwent fibrinolysis, 60.4% had low P/F:PASP and 39.6% had high P/F:PASP ratio (χ2=3.32, p=0.05). P/F:PASP ratio was a predictor of fibrinolysis (OR 0.83, 95% CI 0.72–0.96, p=0.011), with lower ratio increasing the probability of fibrinolysis. This result was independent from PESI (OR 0.84, 95% CI 0.72–0.97, p=0.015). P/F:PASP ratio was also a predictor of IHM (OR 0.62, 95% CI 0.38–1, p=0.05).

During FU, there was no difference in mortality between P with low or high P/F:PASP ratio (8.5% vs. 10.4%, respectively; Kaplan-Meier χ2=0.095; p=0.758).

Conclusions

In IH risk PE, low P/F:PASP ratio was associated with analytical, electrocardiographic and echocardiographic risk features. In this study, P/F:PASP ratio was a predictor of short term prognosis, allowing identification of P at higher risk of fibrinolysis and IHM, but it was not useful for long term prognosis, as 2-year mortality was similar between the groups. Therefore, this ratio, as a measure of both respiratory failure and pressure overload, might allow refinement in risk stratification of P with IH risk PE.

Funding Acknowledgement

Type of funding sources: None.

Prognostic value of relative wall thickness in heart failure with preserved ejection fraction: what is the best method for its calculation?

Background

The HFA-PEFF diagnostic algorithm is a recently published tool to help in the diagnosis of heart failure with preserved ejection fraction (HFpEF). One of the echocardiographic diagnostic criteria is left ventricular (LV) relative wall thickness (RWT), an index of LV concentricity. LV wall thickness can be measured by echocardiography at the posterior wall (PW) and/or the interventricular septum (IVS) in parasternal long axis view. There are three methods of RWT calculation: RWTPW= 2xPW/LV dimension at end diastole (LVDd) – the most used method, RWTIVS = 2 x IVS / LVDd and RWTPW + IVS = (PW + IVS) / LVDd. This study compares the prognostic value of these 3 methods of calculation in patients with acute HFpEF.

Methods

All patients admitted with acute HFpEF in a Cardiology Department during 7 years were included. RWT was considered elevated if superior to its median and was calculated with the 3 formulas. In-hospital mortality (IHM) was evaluated. The primary endpoint (EP) was a composite of all-cause mortality or hospitalization for HF during follow-up of 24 months. Statistical analysis used chi-square and Mann-Whitney U tests, binary logistic regressions, and Kaplan-Meier curves.

Results

478 patients were studied (61.3% female, mean age 79.4±8.3 years). Mean RWTPW, RWTIVS and RWTPW+IVS were 0.46±0.16, 0.50±0.17 and 0.48±0.16, respectively. IHM was 3.4% and primary EP occurred in 57.8%.

High RWTPW was associated with higher LV ejection fraction (LVEF) (p&lt;0.001). Patients with high RWTIVS were older (p=0.044). High RWTPW+IVS was associated with higher left atrial area (p=0.037) and higher LVEF (p=0.002).

There was no statistically significant difference between patients with high and low RWT, calculated using the 3 formulas, in other indices that are commonly used to assess diastolic function, namely in e' and E/e'.

None of the 3 methods of RWT calculation was a predictor of IHM.

Survival analysis showed that patients with high RWTPW had higher incidence of the primary EP (43.2% vs. 16.8%, Kaplan-Meier χ2=5.99; p=0.014), but not patients with high RWTIVS (Kaplan-Meier χ2=0.23; p=0.631) or RWTPW+IVS (Kaplan-Meier χ2=1.92; p=0.166).

RWTPW was a predictor of primary EP (OR 1.81; 95% CI 1.15–2.85; p=0.011) and this result was independent from e' and E/e' (OR 2.96; 95% CI 1.08–8.10; p=0.035).

Conclusion

In this study comparing 3 formulas for calculation of RWT, RWTPW had better risk prediction during follow-up than RWTIVS or RWTPW+IVS. RWTPW was a predictor of all-cause mortality and hospitalization for HF, and was independent from e' and E/e', indexes that are also recommended in HFA-PEFF diagnostic algorithm. Therefore, the formula incorporating PW should be preferred in the evaluation of patients with suspected or diagnosed HFpEF.

Funding Acknowledgement

Type of funding sources: None.

Comparison of the GRACE score, TIMI score and a New Laboratorial Score to predict adverse outcomes in acute coronary syndrome

Introduction

Acute coronary syndrome (ACS) is a clinical entity which includes a heterogeneous group of patients with different outcomes. Risk scores are in this setting a resourceful tool to identify the subset of patients with a worse prognosis, in order to plan therapeutic and surveillance strategies.

Aim

To create a risk score – Laboratory Risk Score (LRS) – which exclusively includes analytical and echocardiographic parameters, as a predictor of adverse outcomes (in-hospital mortality and 1-year mortality), and compare it with other well-known scores: GRACE Score (GS) and TIMI-score (TS).

Methods

A retrospective cohort study was conducted, which included patients admitted in the Cardiology Department with the diagnosis of ACS. In order to calculate the new LRS, the authors attributed the value of 1 to each of the satisfied condition from the following: leucocytes &gt;11,7g/L, hemoglobin &lt;13.3g/dL, red cell distribution width &gt;14%, prothrombinemia &lt;90%, glycaemia at admission &gt;143mg/dL, urea &gt;53.5mg/dL, creatinine &gt;1.16mg/dL, reactive C-protein &gt;1.0mg/dL, maximum troponin &gt;35.0ng/dL, natriuretic brain peptide &gt;416 pg/dL and left ventricular ejection fraction &lt;40%. LRS resulted from the sum of the satisfied conditions.

ROC curves for LRS, GS and TS to predict in-hospital mortality and to predict 1-year mortality were constructed. The statistical analysis was performed in SPSS and Medcalc. p value &lt;0.05 was considered statistically significant.

Results

1714 patients (70.4% male, average age 69±13 years-old) were included in this study. Intra-hospital mortality rate was 6.8% and 1-year mortality rate after de discharge was 4.8%.

The areas under the ROC curves for predicting in-hospital mortality were the following: 0,790 (LRS, p&lt;0,001), 0,793 (GS, p&lt;0.01), 0.817 (TS, p&lt;0.001). For predicting 1-year mortality, the areas under the ROC curves were: 0,715 (LRS, p&lt;0,001), 0,761 (GS, p&lt;0,001), 0.742 (TS, p&lt;0.001). Pairwise comparison of ROC curves showed no significant differences between the scores.

Conclusion

The above-mentioned risk scores, including the new LRS, are obtained with non-invasive and widely available parameters and displayed a good performance in predicting in-hospital and 1-year mortality. Pairwise comparison of ROC curves demonstrated that the new laboratorial score was not inferior predicting adverse outcomes. The SRL is an easily obtained score, that shows a statistical significance in predicting mortality, especially the prediction of in-hospital mortality.

Funding Acknowledgement

Type of funding sources: None.

Left ventricular noncompaction and EcoScore: prognostic value of a new echographic risk score

Introduction

Left Ventricular Non-Compaction (LVNC) is a rare and underdiagnosed cardiomyopathy, characterized by hypertrabeculation of the left ventricle. This disease is associated with high rates of morbidity and mortality; however, its main adverse prognostic factors are not well established.

Aim

To create a risk score for LVNC based on echocardiographic criteria (EcoScore) to predict the occurrence of adverse events.

Methods

The authors included patients with the diagnosis of LVNC, according to the Jenni Criteria. Clinical and echocardiographic data were evaluated and the occurrence of the following adverse events was reported: hospitalizations due to supraventricular or ventricular tachyarrythmias and heart failure, acute myocardial infarction, stroke, heart transplant and death. The follow-up time was 24 months. ROC curves to predict the occurrence of at least one adverse event were constructed for each echocardiographic parameter. The optimal cut-off obtained from each ROC curve was then used to attribute points (1 point per parameter). The EcoScore resulted from the sum of the obtained points. The authors finally created a ROC curve to predict the occurrence of any adverse event for the EcoScore. The statistical analysis was performed in SPSS. p value &lt;0.05 was considered statistically significant.

Results

33 patients (48.5% male, age at diagnosis 45.9±21 years) were included in this study. The optimal cut-offs for each parameter obtained from the ROC curves were the following: left ventricle dyastolic diameter &gt;55mm, left atrial diameter &gt;40mm, pulmonary artery systolic pressure &gt;22mmHg and left ventricle ejection fraction &lt;40%. The area under the curve for the EcoScore to predict any adverse event was 0.850 (p=0.017) and an EcoScore &gt;1 had a sensibility of 85.7% and a specificity of 70%.

Conclusion

The EcoScore accurately predicted the occurrence of at least one adverse event in this population. Thus, it could be a good tool in the daily practice to select patients who may benefit from a more aggressive surveillance and treatment.

Funding Acknowledgement

Type of funding sources: None.

Semiquantitative analysis of interim 18F-FDG PET is superior in predicting outcome in Hodgkin lymphoma patients compared to visual analysis

PURPOSE

To investigate the prognostic value of interim PET (PETi) in adult HL patients, comparing visual with semiquantitative analysis.

MATERIAL AND METHODS

Retrospective analysis of Hodgkin's lymphoma (HL) patients diagnosed between 2012 and 2016 in the Onco-hematology Department of Instituto Português de Oncologia - Porto (median follow-up: 46.5 months [2.6-66.4]). Fifty-eight patients with available PET at diagnosis (PET0) and PETi data were included. PETi scans were analyzed according to Deauville 5-point scale (5-PS), and cut-off values for changes in maximum standardized uptake value [SUVmax], peak SUV [SUVpeak], metabolic tumour volume [MTV] and total lesion glycolysis index [TLG] between PETi and PET0 were computed using ROC analysis. Visual and semiquantitative data were compared with each other in the prediction of patient outcomes.

RESULTS

Semiquantitative analysis obtained a higher sensitivity for persistent/relapsed disease compared to the 5-PS (70% vs. 10%, respectively), but lower specificity. It also demonstrated better predictive performance for response to first-line therapy (negative predictive value >92%). The positive predictive value was similar for all five measurements. At 60 months of follow-up, there was a significant difference between the progression free survival (PFS) curves of patients with positive and negative PETi according to ΔSUVmax (56.9% vs. 88.0%, p<0.05), ΔSUVpeak (55.9% vs. 88.1%, p<0.05), ΔMTV (35.3% vs. 88.7%, p<0.05), and ΔTLG (42.4% vs. 88.1%, p<0.05). Statistical significance was not reached when considering 5-PS results.

DISCUSSION

PETi interpretation according to a semiquantitative approach appears to discriminate HL patients better than the visual 5-PS analysis. This could allow better detection of persistent or early relapsed disease, while a negative PETi result could support de-escalating therapy intensity.

Awareness on the coronary heart disease patient - a case series

Funding Acknowledgements

Type of funding sources: None.

Background

Each year cardiovascular disease (CVD) causes 3.9 million deaths in Europe, accounting for 45% of all deaths. CVD are especially relevant not only due to the high mortality rate related to them, but also due to the disability associated with them. In Portugal, one of the specific skills of the medical-surgical nurse is to take care of the person and family / caregivers experiencing complex medical processes (such as acute coronary syndrome - ACS), resulting from chronic disease (such as coronary heart disease - CHD). The medium-range theory of transitions, by Meleis and collaborators, helps to frame the theoretical aspects in nursing practice. Nursing approaches to the person with CHD, are often focused on transmitting knowledge and teaching abilities, regardless of the perception the person may have of the need to pursue changes in his/her life.

Purpose

This study aimed at gathering information on how a person perceives, has knowledge, and recognises an acute coronary event as a moment of transition. It is intended to evaluate the level of awareness the person has of his/her situation in this health-illness transition, as to incorporate an approach based upon the transition’s theory.

Methods

The study was conducted on a Cardiology ward and Intensive Care Unit of a tertiary hospital in Northern Portugal, on the second half of September 2020. All patients admitted with an ACS were eligible. A qualitative research framework was adopted, using the semi-structured interview. When phrasing some questions, the phenomenological approach was adopted.

Results

Four patients were included. Their interviews showed a wide variability of knowledge about the motive for admission or what caused it; there was an uneven perception of the severity of the event; in general, they did not recognize the need to make changes in their lives or externalized the responsibilities for it. This study was limited by a reduced number of interviews conducted, limiting the generalization of the findings and conclusions, though it was not the purpose of this exercise. Also, the interviews were performed in different moments after admission, so some of the patients had already been approached by the nursing staff in moments of health education, which may lead to information bias.

Conclusions

The traditional health education approach based on teaching the patients a set number of items needed to achieve a healthier lifestyle after an ACS, seem to produce very variable effects on how the person recognizes, perceives, and knows about his/her condition. The transition theory framework may be useful to engage patients in the process and, considering the reduced length of stay in the hospital, it is necessary the transition of care to the community. Awareness is a central concept in the patient"s adaptive process and, therefore, a major theme for nursing practice. Considering the apparent scarcity of evidence about it, it reveals to be an area of future investment.

AB0848 PARTICIPATION OF UNDERGRADUATE MEDICAL STUDENTS AS INVESTIGATORS IN A RHEUMATOLOGIC COHORT: IMPACT ON DEPRESSION, ANXIETY & STRESS SCALE

Background:

Mental health was widely affected during the new coronavirus pandemic. In addition, some measures adopted by most countries in order to contain the virus spread, such as isolation and social distancing, leading to the interruption of routine activities, including partial or complete interruption of face-to-face classes may be associated with increased stress, depression and anxiety among undergraduate medical students (1). From March to September, 2020, the Brazilian Society of Rheumatology carried out the Mario Pinotti II Project (MPII), a prospective, multicenter, observational cohort study designed to monitor the COVID-19 in patients with rheumatic disease on hydroxychloroquine, using periodic telephone calls performed by undergraduate medical students (2).

Objectives:

To compare the mental health status of medical students who were participating from the MPII with theirs colleagues not involved in this project.

Methods:

A web-based survey via google forms platform was developed by a panel composed of undergraduate medical students, rheumatologists, medical school professors, and a psychology professor. It included details on demographic and life habits data and domains regarding depression, anxiety and stress, using the DASS-21 (Depression, Anxiety & Stress Scale), Brazilian version. Data collection occurred from July 20th to August 31st, 2020. Statistical analysis was performed using the SPSS version 20.0. Univariate and multivariate linear regression analysis were performed to verify associations with the DASS-21, defined as dependent variable. A p-value < 0.05 was deemed as significant. This study was approved by the Institutional Research Ethics Committee.

Results:

A total of 684 undergraduate medical students were included in this study, of whom 228 as MPII volunteers (VG) and 456 as control group (CG). Median age was 23 years (IQ 21-24) and the CG was older than the VG (p<0.03). Most of them were white (68.8%) and women (63%). There were no significant differences regarding comorbidities, ethnicity, smoking status, alcohol intake and physical activity. Older age, male gender, participation of MPII study, absence of a worsening in sleep pattern during the pandemic and a lower number of prior comorbidities were associated with lower DASS21 scores, suggesting a better mental health (Table 1).

Conclusion:

Several aspects may be involved with mental health, including increased emotional maturity, gender and sleep pattern. Although with marginal independent association, medical students with participation in the MPII study had better mental health than their student colleagues not engaged with this research. Our data pointed out that voluntary participation in a research project which foresees interaction by telephone contact with rheumatic patients, professors, rheumatologists, and colleagues is associated with better mental health.

References:

[1]Meo SA, Abukhalaf AA, Alomar AA, Sattar K, Klonoff DC. Covid-19 pandemic: Impact of quarantine on medical students’ mental wellbeing and learning behaviors. Pakistan J Med Sci 2020;36(COVID19-S4):S43–8.

[2]Gomides A, Ferreira G, Kakehas A, Lacerda M, Marques C, Paiva E et al. Impact of chronic use of antimalarials on SARS-COV-2 infection in patients with immune-mediated rheumatic diseases: protocol design for a multicentric observational cohort in Brazil. JMIR Research Protocols, 2020.Preprint

Table 1.

Univariate and multivariate analysis of predictors associated to the DASS-21 in undergraduate medical students during the COVID-19 pandemic

Univariate analysisMultivariate analysisVariableB95%CIp-ValueB95%CIp-ValueAge-0.32-0.61 to -0.030.03-0.47-0.81 to -0.130.008Female gender4.883.021 to 6.76<0.001---Stable love relationship-2.49-4.35 to -0.640.008-2.5-4.4 to -0.590.01Number of previous comorbidities reported4.693.71 to 5.68<0.0014.823.73 to 5.92<0.001MP-II volunteering-2.81-4.74 to -0.860.005---Worsening in sleep pattern6.414.62 to 8.20<0.0015.013.07 to 6.96<0.001

Disclosure of Interests:

None declared

POS1252 COVID-19 IN PATIENTS WITH RHEUMATIC DISEASES ON CHRONIC USE OF HYDROXYCHLOROQUINE IN A LARGE BRAZILIAN COHORT – A 24-WEEK PROSPECTIVE STUDY

Background:

The role of chronic use of hydroxychloroquine (HCQ) in rheumatic disease (RD) patients during the SARS-CoV-2 pandemic is still subject of discussion.

Objectives:

To compare the occurrence of COVID-19 and its outcomes between RD patients on HCQ use with individuals from the same household not taking the drug during community viral transmission in an observational prospective multicenter study in Brazil.

Methods:

Participants were enrolled and monitored through 24-week (From March 29th to Sep 30th, 2020) regularly scheduled phone calls performed by trained medical professionals. Epidemiological and demographic data, as well as RD disease activity status and current treatment data, specific information about COVID-19, hospitalization, need for intensive care, and death was recorded in both groups and stored in the Research Electronic Data Capture (REDCap) database. COVID-19 was defined according to the Brazilian Ministry of Health (BMH) criteria. The statistical analysis was performed using IBM-SPSS v.20.0 software. Group comparisons were made using the Man-Whitney, Chi-Square and Fisher Exact Test, as well as multivariate regression models adjusted to confounders. Survival curves were performed using Kaplan-Meier analysis.

Results:

A total of 10,427 participants mean age (SD) of 44.04 (14.98) years were enrolled, including 6004 (57.6%) rheumatic disease patients, of whom 70.8% had systemic lupus erythematosus (SLE), 6.7% rheumatoid arthritis (RA), 4% primary Sjögren’s syndrome (pSS), 1.8% mixed connective tissue disease (DMTC), 1% systemic sclerosis (SSc) and others (15.9), including overlap syndromes. In total, 1,132 (10.8%) participants fulfilled criteria for COVID-19, being 6.7% RD patients and 4.1% controls (p=0.002). A recent influenza vaccination had a protective role (p<0.001). Moderate and severe COVID-19 included the need for hospitalization, intensive care, mechanical ventilation or death. Infection severity was not different between groups (p=0.391) (Table 1). After adjustments for multiple confounders, the main risk factors significantly associated with COVID-19 were higher education level (OR=1.29 95%CI 1.05-1.59), being healthcare professionals (OR=1.91; 95%CI 1.45-2.53), presence of two comorbidities (OR=1.31; 95%CI 1.01-1.66) and three or more comorbidities associated (OR=1.69; 95%CI 1.23-2.32). Interestingly, age >=65 years (OR=0.20; 95%CI 0.11-0.34) was negatively associated. Regarding RD, the risk factors associated with COVID-19 diagnosys were SLE (OR= 2.37; 95%CI 1.92-293), SSc (OR=2.25; 95%CI 1.05-4.83) and rituximab use (OR=1.92; 95%CI 1.13-3.26). In addition, age >=65 years (OR=5.47; 95%CI 1.7-19.4) and heart disease (OR=2.60; 95%CI 1.06-6.38) were associated with hospitalization. Seven female RD patients died, six with SLE and one with pSS, and the presence of two or more comorbidities were associated with higher mortality rate.

Conclusion:

Chronic HCQ use did not prevent COVID-19 in RD compared to their household cohabitants. Health care profession, presence of comorbidities LES, SSc and rituximab were identified as main risk factors for COVID-19 and aging and heart disease as higher risk for hospitalization. Our data suggest these outcomes could be considered to manage them in clinical practice.

Table 1.

Frequency and severity of COVID-19 in patients with rheumatic diseases on chronic use of hydroxychloroquine compared to their household controls

COVID-19 outcomesTotal(%)GroupsPPatients(%)Controls (%)DiagnosisNo9256 (89.1)5300 (88.3)3956 (90.2)0.002Yes1132 (10.9)704 (11.7)428 (9.8)SeverityMild1059 (93.6)662 (94.0)397 (92.8)0.391Moderate52 (4.6)32 (4.5)20 (4.7)Severe21 (1.9)10 (1.4)11 (2.6)

HCQ: hydroxychloroquine.

Moderate and severe COVID-19 included the need for any of the following: hospitalization, intensive care, mechanical ventilation or death.

Acknowledgements:

To the Brazilian Society of Rheumatology for technical support and rapid nationwide mobilization.

To all the 395 interviewers (medical students and physicians) who collaborated in the study and the participants

To CNPq (Number 403442/2020-6)

Disclosure of Interests:

None declared

NISAR-F SCORE: a simple risk stratification tool for patients implanted with cardiac resynchronization therapy

Funding Acknowledgements

Type of funding sources: None.

Introduction

Individualized estimation of prognosis after cardiac resynchronization therapy (CRT) remains challenging. Outcomes in this group of patients are influenced by multiple factors and a comprehensive and customized approach to estimate prognosis after CRT is lacking

Aims

To develop and validate a simple prognostic score for patients implanted with CRT (NISAR-F score), based on readily available clinical and echocardiographic variables to predict the combined endpoints of death or hospitalization in 24 months.

Methods

A single-centre retrospective study was conducted with inclusion of all consecutive patients who underwent CRT implantation between 2012 and 2019. Follow-up started after CRT implantation and ended upon death, hospitalization or 24 months after study entry. Survival analysis was performed using a multivariate Cox regression model, in order to analyze the effect on survival /hospitalization in 24 months of the following factors: age, gender, NYHA Class III-IV, ischemic heart failure, type 2 diabetes, arterial hypertension, dyslipidemia and ejection fraction &lt; 21%. According to the analysis, points were attributed to each factor. Afterwards, the NISAR-F score was calculated for each patient, summing the points of each variable. The authors finally created ROC curves for the NISAR-F score to predict the occurrence of the combined endpoint in 2 groups of patients: CRT responders (ejection fraction increase of at least 10% after CRT implantation) and CRT non-responders. The statistical analysis was performed in SPSS.

Results

102 patients were included in the study (75.4% male, mean age 68 ± 10.46 years). 10(9.8%) of the patients were re-hospitalized and 8 (7.8%) died during the 24-month follow-up.  After calculating NISAR-F score for each patient, area under ROC curves were obtained. The analysis of the ROC curves allows us to confirm the good performance of the score created [responders group (AUC 0.812) vs non-responders (AUC 0.721)].

Conclusion The NISAR-F score is a useful tool to predict the combined endpoint (mortality and hospitalization in 24 months) after CRT implantation, in both responders and non-responders, revealing good performance of this new and simple score based only on clinical and echocardiographic variables.

Identification of Streptococcus pneumoniae in hospital-acquired pneumonia in adults

Hospital-acquired pneumonia (HAP) is often more severe and life-threatening than community-acquired pneumonia (CAP). The role of Streptococcus pneumoniae in CAP is well-understood, but its role in HAP is unclear. The objective of this study was to summarize the available literature on the prevalence of S. pneumoniae in HAP episodes. We searched MEDLINE for peer-reviewed articles on the microbiology of HAP in individuals aged ≥18 years, published between 2008 and 2018. We calculated pooled estimates of the prevalence of S. pneumoniae in episodes of HAP using a random-effects, inverse-variance-weighted meta-analysis. Forty-seven of 1908 articles met the inclusion criteria. Bacterial specimen isolation techniques for microbiologically defined HAP episodes included bronchoalveolar lavage, protective specimen brush, tracheobronchial aspirate and sputum, as well as blood culture. Culture was performed in all studies; five studies also used urine antigen detection (5/47; 10.6%). S. pneumoniae was identified in 5.1% (95% confidence interval (CI): 3.8-6.6%) of microbiologically defined HAP episodes (N = 20), with 5.4% (95% CI: 4.3-6.7%, N = 29) in ventilator-associated HAP and 6.0% (95% CI: 4.1-8.8%, N = 6) in non-ventilator-associated HAP. S. pneumoniae was identified in 5.3% (95% CI: 4.5-6.3%) of HAP occurring in the intensive care unit (ICU, N = 41) and in 5.6% (95% CI: 3.3-9.5%, N = 5) outside the ICU. A higher proportion of early-onset HAP (10.3%; 95% CI: 8.3-12.8%, N = 16) identified S. pneumoniae as compared with late-onset HAP (3.3%; 95% CI: 2.5-4.4%, N = 16). In conclusion, S. pneumoniae was identified by culture in 5.1% of microbiologically defined HAP episodes. The importance of HAP as part of the disease burden caused by S. pneumoniae merits further research.

Interrater Reliability of the Pediatric Neuromuscular Recovery Scale in Children with Spina Bifida

Purpose: The purpose of this study was to examine the interrater reliability of the Pediatric Neuromuscular Recovery Scale (Peds NRS) to classify motor capacity in children with myelomeningocele (MMC) form of spina bifida.Methods: Twenty-one children with MMC (1.5-10 years of age) were each scored on the Peds NRS three times: two live testing sessions and one video recorded session. Every child was scored by two physical therapists and one occupational therapist. Interrater reliability was analyzed using intraclass correlation coefficients (ICC) for individual items and the summary score.Results: Strong interrater reliability was determined for the overall Peds NRS score (ICC = 0.89; 95% CI, .80-.95). Eleven of 16 individual items exhibited good to excellent reliability (ICC ≥ 0.80). Pediatric clinicians were able to reliably administer and score the Peds NRS on children with MMC, representing a wide range of ages and functional levels.

Short communication: Production performance and nutrient digestibility of lactating dairy cows fed diets with and without addition of a live-yeast supplement

The objective of this study was to evaluate the use of a live-yeast product when feeding relatively high-forage diets to high-producing cows in mid lactation. Eight primiparous [607 ± 43 kg of body weight (BW) and 130 ± 16 d in milk (DIM) at the beginning of the experiment] and 16 multiparous (706 ± 63 kg of BW and 137 ± 22 DIM at the beginning of the experiment) Holstein cows were blocked by parity and DIM, and randomly assigned to 1 of 2 diets (control vs. yeast) for a 12-wk period according to a randomized complete block design. The formulated diets contained 50.4% corn silage, 10.4% alfalfa hay, and 39.2% concentrate. The yeast diet was formulated to provide approximately 5.4 × 10¹¹ cfu/d of Saccharomyces cerevisiae (BeneSacc; Global Nutritech Biotechnology LLC, Richmond, VA). Total-tract nutrient digestibility was estimated using 240-h undigested neutral detergent fiber (NDF) as an internal marker. Supplementing live yeast to lactating dairy cows did not affect dry matter intake (25.0 kg/d), milk yield (38.6 kg/d), milk fat concentration (4.78%), milk fat yield (1.83 kg/d), milk protein concentration (3.09%), milk protein yield (1.18 kg/d), milk lactose concentration (4.79%), milk lactose yield (1.84 kg/d), BW gain (-0.05 kg/d), or body condition score gain (0.16 units). The digestibility of dry matter was greater for the control treatment than for the yeast treatment (69.3 and 67.1%, respectively), but the digestibilities of crude protein (61.5%), NDF (40.5%), and starch (98.6%) were not affected by treatment. In conclusion, supplementation of live yeast did not affect production performance or nutrient digestibility of high-producing cows in mid lactation. The reasons for the lack of effect are not clear, but an evaluation of interactions between yeast and rumen buffer supplementation is warranted.

Production performance and nutrient digestibility of lactating dairy cows fed low-forage diets with and without the addition of a live-yeast supplement

We aimed to evaluate the use of a live-yeast product as a means to attenuate plausible nutritional disturbances when feeding relatively low-forage diets containing rapidly fermentable carbohydrates (i.e., wheat) to high-producing cows in early to mid lactation. Eight primiparous [mean ± SD; 569 ± 35 kg of body weight (BW) and 80 ± 29 d in milk (DIM) at the beginning of the experiment] and 16 multiparous (665 ± 67 kg of BW and 64 ± 10 DIM at the beginning of the experiment) Holstein cows were blocked by parity and DIM, and randomly assigned to 1 of 2 diets (control vs. yeast) for a 12-wk-long period according to randomized complete block design. The formulated diets contained 36.7% corn silage, 8.3% alfalfa hay, and 55% concentrate. The yeast diet was formulated to provide approximately 5.4 × 10¹¹ cfu/d of Saccharomyces cerevisiae (BeneSacc; Global Nutritech Biotechnology LLC, Richmond, VA). Total-tract nutrient digestibility was estimated using 240-h undigested neutral detergent fiber (NDF) as an internal marker. Dry matter intake, milk yield, and milk component concentrations and yields were analyzed using repeated measures. The statistical model for these variables included the effects of block, treatment, the block by treatment interaction, week, the treatment by week interaction, and the random residual error. The statistical model for analyzing BW gain, body condition score gain, and dry matter and nutrient digestibilities included the effects of block, treatment, and the random residual error. Supplementing live yeast to lactating dairy cows did not affect dry matter intake (26.0 kg/d), milk yield (48.1 kg/d), milk fat concentration (3.61%), milk fat yield (1.72 kg/d), milk protein concentration (2.96%), milk protein yield (1.43 kg/d), milk lactose concentration (4.84%), milk lactose yield (2.35 kg/d), milk urea nitrogen (7.99 mg/dL), body weight gain (0.62 kg/d), and body condition score gain (0.02 units; all averages of the 2 treatments). The digestibilities of dry matter (70.2%), crude protein (71.4%), NDF (36.4%), and starch (99.8%) were not affected by treatments. In conclusion, the supplementation of the live yeast did not affect production performance and nutrient digestibility of high-producing dairy cows. A potential interaction between live-yeast supplementation and NDF passage rate, which may have hindered the beneficial effects of live-yeast supplementation on production performance and nutrient utilization, deserves further research.

Peptide receptor radionuclide therapy with 177Lu-DOTA-TATE as a promising treatment of malignant insulinoma: a series of case reports and literature review

INTRODUCTION

Insulinomas are a rare type of pancreatic neuroendocrine tumours characterized by insulin hypersecretion. They are considered malignant when metastases are present. Traditional therapies often promote only temporarily symptomatic relief and may be associated with severe adverse effects. There is scarce experience in treating malignant insulinomas with peptide receptors radionuclide therapy (PRRNT).

PATIENTS AND METHODS

We describe PRRNT results in four patients with inoperable malignant insulinomas with poorly controllable hypoglycaemia. All patients received therapy with ¹⁷⁷Lu-DOTA-TATE after conventional therapies failed in controlling disease progression and symptoms. The activity administered per cycle was 4.8-7.4 GBq. The interval between cycles was 10-16 weeks. Haematology, liver and kidney function tests were performed before treatment initiation and 5 and 10 weeks after each cycle.

RESULTS

Patient 1 presented significant clinical benefit for 13 months after PRRNT, with imaging improvement. Patient 2 obtained reduction of the number and severity of hypoglycaemic episodes during 15 months after therapy. Patient 3 is asymptomatic since PRRNT first cycle performed 23 months ago and revealed significant imaging improvement. Patient 4 had resolution of hypoglycaemia only 3 days after PRRNT first cycle and today, 16 months after therapy, the disease seems to be in remission and the patient maintains euglycaemic state. PRRNT was well tolerated, with only hematologic grade 2 toxicity in patient 1 and mild kidney toxicity in patient 3.

CONCLUSIONS

After the start of ¹⁷⁷Lu-DOTA-TATE all patients achieved hypoglycaemia symptomatic control and had evident improvement of their quality of life. Three patients showed imagiological improvement suggesting reduced tumour load.

Production performance, nutrient digestibility, and milk fatty acid profile of lactating dairy cows fed corn silage- or sorghum silage-based diets with and without xylanase supplementation

The objective of this study was to evaluate the effects of supplementing xylanase on production performance, nutrient digestibility, and milk fatty acid profile in high-producing dairy cows consuming corn silage- or sorghum silage-based diets. Conventional corn (80,000 seeds/ha) and brown midrib forage sorghum (250,000 seeds/ha) were planted, harvested [34 and 32% of dry matter (DM), respectively], and ensiled for more than 10 mo. Four primiparous and 20 multiparous Holstein cows were randomly assigned to 1 of 4 diets in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments and 19-d periods. Treatment diets consisted of (1) corn silage-based diet without xylanase, (2) corn silage-based diet with xylanase, (3) sorghum silage-based diet without xylanase, and (4) sorghum silage-based diet with xylanase. The xylanase product was supplemented at a rate of 1.5 g of product/kg of total DM. Corn silage had higher concentrations of starch (31.2 vs. 29.2%), slightly higher concentrations of crude protein (7.1 vs. 6.8%) and fat (3.7 vs. 3.2%), and lower concentrations of neutral detergent fiber (36.4 vs. 49.0%) and lignin (2.1 vs. 5.7%) than sorghum silage. Xylanase supplementation did not affect DM intake, milk yield, milk fat percentage and yield, milk protein percentage and yield, lactose percentage and yield, and 3.5% fat-corrected milk yield. Cows consuming corn silage-based diets consumed 13% more DM (28.8 vs. 25.5 kg/d) and produced 5% more milk (51.6 vs. 48.9 kg/d) than cows consuming sorghum silage-based diets. Milk from cows consuming sorghum silage-based diets had 16% greater fat concentrations (3.84 and 3.30%) than milk from cows consuming corn silage-based diets. This resulted in 8% greater fat yields (1.81 vs. 1.68 kg/d). Silage type did not affect milk protein and lactose concentrations. Xylanase supplementation did not affect nutrient digestibility. Cows consuming corn silage-based diets showed greater DM (77.3 vs. 73.5%), crude protein (78.0 vs. 72.4), and starch (99.2 vs. 96.5%) digestibilities than cows consuming sorghum silage-based diets. In conclusion, xylanase supplementation did not improve production performance when high-producing dairy cows were fed corn silage- or sorghum silage-based diets. In addition, production performance can be sustained by feeding sorghum silage in replacement of corn silage.

Short communication: Effect of corn planting population on phosphorus concentration and uptake in corn silage

Greater utilization of nutrients reduces the potential runoff of nutrients to bodies of water. The objective of this study was to determine the concentration of P in corn biomass to estimate the removal of P from the soil when planting corn at different population levels. Whole-plant corn samples were collected during an on-farm research project conducted previously. The study included 7 different growing and harvesting conditions. In each cornfield, corn was planted in plots at a theoretical seeding rate of 55,000, 70,000, 85,000, and 100,000 seeds/ha. Each seeding rate had 4 replicates within each field. At harvesting time, 5 consecutive plants from the 2 center rows and at 2 randomly selected spots within each plot were cut by hand at 15 cm above ground. Whole plants were weighed and chopped. After mixing thoroughly, a sample of the chopped material was placed in a bag, immediately placed in a cooler with dry ice, and transferred to the laboratory for storage. After thawing and drying, samples were ground and analyzed for P concentration. Single plant biomass and the number of standing plants at harvesting were used to determine dry matter yield. Total extraction of P was estimated as the product between plant biomass and P concentration. All variables were analyzed using a statistical model that included the effects of field, planting population, planting population nested within field, and random residual error. The concentration of P in the corn plant was greatest for 55,000 and 70,000 plants/ha (0.250% dry matter) and least for 85,000 and 100,000 plants/ha (0.235% dry matter), whereas the uptake of P through the harvested biomass increased when corn planting population increased. In conclusion, increasing the planting population of corn for silage can increase P uptake from the soil, therefore reducing the potential runoff of P to bodies of water.

Nutritional composition and in vitro digestibility of grass and legume winter (cover) crops

In dairy farming systems, growing winter crops for forage is frequently limited to annual grasses grown in monoculture. The objectives of this study were to determine how cropping grasses alone or in mixtures with legumes affects the yield, nutritional composition, and in vitro digestibility of fresh and ensiled winter crops and the yield, nutritional composition, and in vitro digestibility of the subsequent summer crops. Experimental plots were planted with 15 different winter crops at 3 locations in Virginia. At each site, 4 plots of each treatment were planted in a randomized complete block design. The 15 treatments included 5 winter annual grasses [barley (BA), ryegrass (RG), rye (RY), triticale (TR), and wheat (WT)] in monoculture [i.e., no legumes (NO)] or with 1 of 2 winter annual legumes [crimson clover (CC) and hairy vetch (HV)]. After harvesting the winter crops, corn and forage sorghum were planted within the same plots perpendicular to the winter crop plantings. The nutritional composition and the in vitro digestibility of winter and summer crops were determined for fresh and ensiled samples. Growing grasses in mixtures with CC increased forage dry matter (DM) yield (2.84 Mg/ha), but the yield of mixtures with HV (2.47 Mg/ha) was similar to that of grasses grown in monoculture (2.40 Mg/ha). Growing grasses in mixtures with legumes increased the crude protein concentration of the fresh forage from 13.0% to 15.5% for CC and to 17.3% for HV. For neutral detergent fiber (NDF) concentrations, the interaction between grasses and legumes was significant for both fresh and ensiled forages. Growing BA, RY, and TR in mixtures with legumes decreased NDF concentrations, whereas growing RG and WT with legumes did not affect the NDF concentrations of either the fresh or the ensiled forages. Growing grasses in mixtures with legumes decreased the concentration of sugars of fresh forages relative to grasses grown in monoculture. Primarily, this decrease can be attributed to low concentrations of sugars of mixtures with HV (10.5%). Growing grasses in mixtures with legumes reduced the fiber digestibility of both winter crops (75.7% to 72.8% NDF). Growing grasses in mixtures with legumes did not affect estimated DM yield, nutritional composition, or digestibility of the succeeding summer crops. In conclusion, growing grasses in mixtures with legumes as winter forage crops can increase forage estimated DM yields and its nutritional quality in dairy farming sytems.