Blood glucose monitoring in critically ill adult patients: type of sample and method of analysis. Systematic review and meta-analysis.

INTRODUCTION: The clinical guideline for the management of sepsis, recommends using arterial blood samples for glycaemic control. A multicentre study in 86 Spanish intensive care units (ICU) revealed that 85.4% of ICUs used capillary puncture. OBJECTIVE: To analyse the reliability of glycaemia by comparing different blood samples (arterial, venous, capillary) and instruments (glucometers, gasometers, central laboratory). Secondarily, to estimate the effect of confounding variables and the performance of measuring instruments as determined by different quality standards. METHODOLOGY: Systematic review and meta-analysis with search in PubMed, CINAHL and Embase databases in September-2021 and September-2022, with no time or language limits. Grey literature sources: DART-Europe, OpenGrey and Google Scholar. Results summarised by qualitative (description of results, study characteristics) and quantitative (meta-analysis to assess standardised mean difference) synthesis. Methodological quality of articles assessed with Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). PROTOCOL: https://osf.io/ DOI 10.17605/OSF.IO/T8KYP. RESULTS: A total of 32 articles and 5451 patients were included. No discrepancies were obtained between arterial glucometer vs laboratory samples [bias (95%CI): 0.01 (-0.12 to 0.14) mg/dL]. In contrast, arterial samples with a gasometer did significantly overestimate [bias (95%CI): 0.12 (0.01 to 0.24) mg/dL]. The same trend is seen in capillaries with a glucometer, although not significantly [bias (95%CI): 0.07 (--0.02 to 0.15) mg/dL]. There is discrepancy between studies on the effect of haematocrit and acid-base balance. The greatest consensus is on the poor agreement of glucometer with capillary vs laboratory samples in the presence of shock and vasopressor support, renal failure or during vitamin C treatment. CONCLUSIONS: The evidence to date recommends the use of arterial blood with a blood glucose meter for better reliability of glycaemic analysis and less effect of possible confounding variables, frequently present in the critically ill adult patient.

Predictive validity of the Clinical Frailty Scale-España on the increase in dependency after hospital discharge.

INTRODUCTION: The frailty present at hospital admission and the stressors to which patients are subjected during their stay may increase dependency at hospital discharge. OBJECTIVES: To assess the predictive validity of the Clinical Frailty Scale-España (CFS-Es) on increased dependency at 3 and 12 months (m) after hospital discharge. METHODOLOGY: Multicentre cohort study in 2020-2022. Including patients with >48 h stay in intensive care units (ICU) and non-COVID-19. VARIABLES: pre-admission frailty (CFS-Es). Sex, age, days of stay (ICU and hospital), dependency on admission and at 3 m and 12 m after discharge (Barthel index), muscle weakness (Medical Research Council Scale sum score <48), hospital readmissions. STATISTICS: descriptive and multivariate analysis. RESULTS: 254 cases were included. Thirty-nine per cent were women and the median [Q1-Q3] age was 67 [56-77] years. SAPS 3 on admission (median [Q1-Q3]): 62 [51-71] points. Frail patients on admission (CFS-Es 5-9): 58 (23%). Dependency on admission (n = 254) vs. 3 m after hospital discharge (n = 171) vs. 12 m after hospital discharge (n = 118): 1) Barthel 90-100: 82% vs. 68% vs. 65%. 2) Barthel 60-85: 15% vs. 15% vs. 20%. 3) Barthel 0-55: 3% vs. 17% vs. 15%. In the multivariate analysis, adjusted for the variables recorded, we observed that frail patients on admission (CFS-Es 5-9) are 2.8 times (95%CI: 1.03-7.58; p = 0.043) more likely to increase dependency (Barthel 90-100 to <90 or Barthel 85-60 to <60) at 3 m post-discharge (with respect to admission) and 3.5 times (95%CI: 1.18-10.30; p = 0.024) more likely to increase dependency at 12 m post-discharge. Furthermore, for each additional CFS-Es point there is a 1.6-fold (95%CI: 1.01-2.23; p = 0.016) greater chance of increased dependency in the 12 m following discharge. CONCLUSIONS: CFS-Es at admission can predict increased dependency at 3 m and 12 m after hospital discharge.

Dual-energy CT in the differentiation between adrenal adenomas and metastases: Usefulness of material density maps and monochromatic images.

OBJECTIVE: To evaluate the behavior of adrenal adenomas and metastases with dual-energy CT, analyzing the attenuation coefficient in monochromatic images at three different levels of energy (45, 70, and 140 keV) and the tissue concentrations of fat, water, and iodine in material density maps, with the aim of establishing optimal cutoffs for differentiating between these lesions and comparing our results against published evidence. MATERIALS AND METHODS: This retrospective case-control study included oncologic patients diagnosed with adrenal metastases in the 6-12 months prior to the study who were followed up in our hospital between January and June 2020. For each case (patient with metastases) included in the study, we selected a control (patient with an adrenal adenoma) with a nodule of similar size. All patients were studied with a rapid-kilovoltage-switching dual-energy CT scanner, using a biphasic acquisition protocol. We analyzed the concentration of iodine in paired water-iodine images, the concentration of fat in the paired water-fat images, and the concentration of water in the paired iodine-water and fat-water images, in both the arterial and portal phases. We also analyzed the attenuation coefficient in monochromatic images (at 55, 70, and 140 keV) in the arterial and portal phases. RESULTS: In the monochromatic images, in both the arterial and portal phases, the attenuation coefficient at all energy levels was significantly higher in the group of patients with metastases than in the group of patients with adenomas. This enabled us to calculate the optimal cutoffs for classifying lesions as adenomas or metastases, except for the arterial phase at 55 KeV, where the area under the receiver operating characteristic curve (AUC) for the estimated threshold (0.68) was not considered accurate enough to classify the lesions. For the arterial phase at 70 keV, the AUC was 0.76 (95% CI: 0.663‒0.899); the optimal cutoff (42.4 HU) yielded 92% sensitivity and 60% specificity. For the arterial phase at 140 keV, the AUC was 0.94 (95% CI: 0.894‒0.999); the optimal cutoff (18.9 HU) yielded 88% sensitivity and 94% specificity). For the portal phase at 55 keV, the AUC was 0.76 (95% CI: 0.663‒0.899); the optimal cutoff (95.4 HU) yielded 68% sensitivity and 84% specificity. For the portal phase at 70 keV, the AUC was 0.82 (95% CI: 0.757‒0.955); the optimal cutoff (58.4 HU) yielded 80% sensitivity and 84% specificity. For the portal phase at 140 keV, the AUC was 0.9 (95% CI: 0.834‒0.987); the optimal cutoff (16.35 HU) yielded 96% sensitivity and 84% specificity. In the material density maps, in the arterial phase, significant differences were found only for the iodine-water pair, where the concentration of water was higher in the group with metastases (1018.8 ±â€¯7.6 mg/cm3 vs. 998.6 ±â€¯8.0 mg/cm3 for the group with adenomas, p < 0.001). The AUC was 0.97 (95% CI: 0.893‒0.999); the optimal cutoff (1012.5 mg/cm3) yielded 88% sensitivity and 96% specificity. The iodine-water pair was also significantly higher in metastases (1019.7 ±â€¯12.1 mg/cm3 vs. 998.5 ±â€¯9.1 mg/cm3 in adenomas, p < 0.001). The AUC was 0.926 (95% CI: 0.807‒0.977); the optimal cutoff (1009.5 mg/cm3) yielded 92% sensitivity and 92% specificity. Although significant results were also observed for the fat-water pair in the portal phase, the AUC was insufficient to enable a sufficiently accurate cutoff for classifying the lesions. No significant differences were found in the fat-water maps or iodine-water maps in the arterial or portal phase or in the water-fat map in the arterial phase. CONCLUSIONS: Monochromatic images show differences between the behavior of adrenal adenomas and metastases in oncologic patients studied with intravenous-contrast-enhanced CT, where the group of metastases had higher attenuation than the group of adenomas in both the arterial and portal phases; this pattern is in line with the evidence published for adenomas. Nevertheless, to our knowledge, no other publications report cutoffs for this kind of differentiation in contrast-enhanced monochromatic images obtained in rapid-kilovoltage-switching dual-energy CT scanners, and this is the first new contribution of our study. Regarding the material density maps, our results suggest that the water-iodine pair is a good tool for differentiating between adrenal adenomas and metastases, in both the arterial and portal phases. We propose cutoffs for differentiating these lesions, although to our knowledge no cutoffs have been proposed for portal-phase contrast-enhanced images obtained with rapid-kilovoltage-switching dual-energy CT scanners.

Relevance of subclinical right ventricular dysfunction measured by feature-tracking cardiac magnetic resonance in non-ischemic dilated cardiomyopathy.

BACKGROUND: Right ventricular (RV) dysfunction in patients with non-ischemic dilated cardiomyopathy (NICM) is associated with cardiovascular events. To analyze the feasibility of assessing RV myocardial deformation by feature tracking (FT)-cardiac magnetic resonance (CMR), and its usefulness as a prognostic marker. METHODS: Retrospective study of NICM patients undergoing CMR. Longitudinal FT-RV free wall (LFT-RVFW) and fractional area change (FAC) were obtained. Correlation with standard RV parameters was studied. An association with combined event (heart failure (HF), ICD implantation or cardiovascular death) was assessed using a logistic regression model. RESULTS: 98 patients (64 ± 13 years) were included. Left ventricular (LV) systolic function (LVEF 29.5 ± 9.6%, 47% with LVEF ≥ 30%) and RV (RVEF 52.2 ± 14.6%, 72% with RVEF ≥ 45%). Follow-up of 38 ± 17 months, 26.5% presented at least one admission for HF. An excellent correlation of LFT-RVFW (r = 0.82) and FAC (r = 0.83) with RVEF was evident. No association of RV-FT parameters with prognosis entire study population was found. However, in patients with LVEF ≥ 30%, admissions for HF were associated with lower LFT-RVFW (-21.6 ± 6.6% vs -31.3 ± 10%; p = 0.006) and FAC (36.6 ± 9.6% vs 50.5 ± 13.4%; p < 0.001) values. Similar differences were observed when only patients with RVEF ≥ 45% were considered. An LFT-RVFW cut-off point of -19.5% and FAC of 36.5% showed good prognostic performance. Decreased LFT-RVFW or FAC represented an independent predictor of combined event in patients with LVEF ≥ 30%. CONCLUSIONS: In NICM patients without severe LV dysfunction, decreased values of LFT-RVFW and/or FAC were associated with HF admissions, independently of RVEF.

Muscle Assessment by Ultrasonography: Agreement with Dual-Energy X-Ray Absorptiometry (DXA) and Relationship with Physical Performance.

BACKGROUND: Different methods have been proposed to study skeletal muscle mass in sarcopenia diagnosis, although all have inherent drawbacks. The aim of this study was to evaluate the utility of muscle ultrasound in muscle assessment by studying its correlation with dual-energy x-ray absorptiometry (DXA) and calf circumference (CC), cut-off values for ultrasound-based detection of low muscle mass, and the correlation with muscle performance. METHODS: Fifty-seven participants older than 70 years, underwent a muscle ultrasound study, DXA, calf circumference (CC) and functional assessment. Ultrasound measurements were taken in the femoral quadriceps (transverse plane) and in the medial gastrocnemius (transverse and longitudinal planes). Muscle function was assessed by gait speed, Short Physical Performance Battery (SPPB) and grip strength. RESULTS: Median age was 78.9 years (IQR 74.9 - 81.9), and 33 were women (57.9%). We found good correlation between muscle thickness of gastrocnemius muscle in transverse and longitudinal plane and appendicular lean mass measured by DXA (r=0.546 and r=0.689 respectively) and good correlations between muscle thickness of gastrocnemius in transverse and longitudinal plane with CC (r=0.651 and r=0.447 respectively). The thickness of gastrocnemius medialis optimal cut-off points for low muscle mass were 18,5mm in the transverse plane (Sensitivity: 77,8%, Specificity: 77,1%), and 17.3mm in the longitudinal plane (Sensitivity: 100%,Specificity: 68.8%). Muscle thickness was also significantly correlated with gait speed, SPPB and grip strength. CONCLUSIONS: Measures of gastrocnemius medialis thickness obtained by ultrasound are reliable and correlate well with DXA and CC values and muscle performance.

Frontal Fibrosing Alopecia: A Retrospective Study of 75 Patients. / Alopecia frontal fibrosante: estudio retrospectivo de 75 pacientes.

BACKGROUND AND OBJECTIVE: Frontal fibrosing alopecia is an increasingly common form of scarring alopecia. The aim of this study was to describe the demographic and clinical characteristics of patients with FFA seen at the trichology unit of a medium-sized regional hospital and to report on treatments used. MATERIAL AND METHOD: We reviewed the medical records of all patients with FFA seen at the trichology unit of Hospital Universitario Infanta Sofía in Madrid, Spain between May 2016 and May 2018. We analyzed associations between disease severity, clinical patterns, need for oral medications, and other characteristics. RESULTS: Seventy-five patients (73 women and 2 men) were studied. Diagnosis was clinical in most cases and 13 cases (17.3%) were confirmed histologically. Median (interquartile range) age at reported onset of symptoms was 61 (12) years. Involvement of the eyebrows was recorded in 70 patients (93.3%) and signs of oral and genital lichen planus in 7 (9.6%). Eleven patients (14.7%) had hypothyroidism and 15 (20.0%) had signs of rosacea. Only 5 of the patients who presented a linear pattern (21.7%) had severe hairline recession. Patients with unstable and/or symptomatic disease (n=24) were treated with oral medications (5-alpha reductase inhibitors, hydroxychloroquine, corticosteroids, and isotretinoin) or intralesional corticosteroids. Eighteen patients (75.0%) achieved disease stability. Ten of the 15 patients with signs of rosacea and 10 of those with facial papules required systemic treatment. CONCLUSION: Most of the patients in this series of FFA were postmenopausal women. The prevalence of oral and genital lichen planus was higher than that observed in the general population. Patients with a linear pattern had less severe disease. Facial papules were more common in younger patients and both facial papules and rosacea were associated with a greater need for oral treatment.

Adaptation and validation of the ICU Mobility Scale in Spain. / Adaptación y validación de la ICU Mobility Scale en España.

OBJECTIVE: To adapt the ICU Mobility Scale (IMS) to the area of intensive care units (ICU) in Spain and to evaluate the metric properties of the Spanish version of the IMS (IMS-Es). METHOD: Descriptive metric study developed in two phases. Phase 1, adaptation to Spanish of the IMS by a team of nurses and physiotherapists (translation, pilot, backtranslation and agreement). Phase 2, analysis of metric properties (convergent, divergent and predictive validity, interobserver reliability, sensitivity and minimum important difference) of the IMS-Es. Patient characteristics (Barthel, Charlson, BMI, sex), sedation/agitation level (RASS), ICU and hospital stays, survival, quality of life (SF-12), muscle weakness (MRC-SS) and mobility (IMS-Es) were recorded in the patients of the MOviPre national multicentre study. RESULTS: After obtaining the IMS-Es, it was implemented in 645 patients from 80 Spanish ICUs between April and June 2017. Convergent validity: moderate correlation between IMS-Es and MRC-SS (r=.389; P<.001) and significant comparison between groups with and without ICU-acquired weakness (P<.001). Divergent validity: no correlation between IMS-Es and BMI [r (95%CI): -.112 (-.232 to .011)], weight [r (95%CI): -.098 (-.219 to .026)], Charlson [r (95%CI): -.122 (-.242 to .001)] and Barthel [r(95%CI): -.037 (-.160 to .087)] and no differences between sexes (P=.587) or BMI categories (P=.412). Predictive validity: moderate and significant correlations with post-ICU hospital stay [r (95%CI): -.442 (-.502 to -.377)] and physical component of SF-12 (PCS) [r (95%CI): .318 (.063 to .534)]; patients without active mobilisation in ICU increased risk of hospital mortality [OR (95%CI): 3.769 (1.428 to 9.947)]. Interobserver reliability: very good concordance between nurses [CCI (95%CI): .987 (.983 to .990)] and nurse-physiotherapist [CCI (95%CI): .963 (.948 to .974)]. Sensitivity to change: small effect on discharge from ICU (d=.273) and moderate effect at 3months after hospital discharge (d=.709). Minimal important difference: 2-point difference cut-off point, 91.1% sensitivity and 100.0% specificity. CONCLUSIONS: The IMS-Es is useful, valid and reliable for implementation by ICU nurses and physiotherapists in assessing the mobility of critical patients.

Perampanel in chronic insomnia.

OBJECTIVES: Insomnia is the most prevalent sleep disorder in the general population, and one of the most frequent reasons for consultation in the Sleep Units. Perampanel is an antiepileptic also effective on the structure of sleep, and in restless legs syndrome. We describe the first study that evaluates perampanel in patients with chronic insomnia. PATIENTS AND METHODS: Observational retrospective cohorts study of 66 patients with chronic resistant insomnia, 33 exposed to perampanel, other 33 as non-exposed group. All patients attended in Neurology or Psychiatry Consultation, from November 2017 to November 2018. Patients included had been treated with more than 4 different drugs in the previous 4 years. We reviewed age, sex, insomnia etiology, years of evolution, number of previously used drugs, and the results of perampanel for insomnia after 3 months of treatment in the exposed cohort, measured by the improvement of 3 or more points in the ISI and Pittsburgh scales, as well as the average of hours of sleep gained. Non-exposed patients were matched with this variables, but never treated with perampanel. RESULTS: We have included 66 patients. In the exposed cohort: we describe 33 patients with chronic resistant insomnia, 20 women (60 %), 13 men (40 %). Average age 53.48 years, average time of evolution: 11.25 years. Main etiology: depression 13 cases (40 %). After the combination of perampanel 2-4 mg (100 %) with antidepressants (17 cases, 51.5 %) or anxiolytics (12 cases, 36.36 %) along 3 months: the total number of hours of sleep improves in 2.5 h, the scale ISI improves by 6 points (± 2.1 SD, p = 0.02), and Pittsburgh scale improves in 4 points (± 1.7, p = 0.04). In non-exposed cohort, the improvement of the ISI scale was 2.2 points (±0.8, p = 0.06), on the Pittsburgh scale was 1.6 points (± 0.5, p = 0.01). The main adverse effect was irritability in 3 patients, without withdrawal perampanel. The treatment was abandoned by 4 patients (12.12%): 1 due to persistent irritability (3%), 2 due to lack of efficacy (6 %), 1 due to pregnancy wish (3 %). CONCLUSION: The combination of Perampanel with an antidepressant, or an anxiolytic, improves the quality of sleep measured by ISI and Pittsburgh scales (statistically significant), probably due to its antagonistic action on glutamate. A clinical trial compared with placebo would be necessary to corroborate these results.

Bovine oocytes show a higher tolerance to heat shock in the warm compared with the cold season of the year.

Heat stress is especially harmful for bovine ovarian follicle development and oocyte competence. In this study, we assessed the effects of heat shock on oocyte maturation in oocytes collected during the cold (February-March; n = 114) or warm (May-June; n = 116) periods of the year. In both cases, cumulus-oocyte complexes were matured under control (38 °C) and heat shock conditions (41.5 °C, 18-21 h of maturation). For each oocyte, nuclear stage, cortical granule distribution and steroidogenic activity of cumulus cells were evaluated. Based on the odds ratio, heat-shocked oocytes were 26.83 times more likely to show an anomalous metaphase II morphology. When matured under heat shock conditions, oocytes obtained in both seasons were similarly affected in terms of nuclear maturation, whereas a seasonal effect was observed on cytoplasmic maturation. For oocytes collected during the cold season, the likelihood to show an anomalous maturation was 25.96 times higher when exposed to the heat treatment than when matured under control conditions. By contrast, oocytes collected during the warm season matured under control or heat shock did not show significant risk of showing an anomalous cytoplasmic maturation. Our findings indicate an increased rate of premature oocytes in response to heat shock as well as a higher tolerance to this stress of oocytes harvested in the warm season compared with those collected in the colder period.

Effects of twinning on the subsequent reproductive performance and productive lifespan of high-producing dairy cows.

This study was designed to determine the effects of twinning on the subsequent reproductive performance and productive lifespan of high milk-producing dairy cows. The data analyzed were taken from complete reproductive records for 4861 Holstein Friesian cows comprising a commercial herd, including data for 12 587 calving events from April 1, 2001 to March 31, 2012. The twinning rate was 5.6%, and 9.6% of the cows delivered twins at least once during their life. Conception rates before Days 90, 120, and 300 postpartum were 20.8%, 36.9%, and 74.5%, and 34.2%, 51.8%, and 85.0% for cows delivering twins and singletons, respectively. Cox regression analysis revealed that twinning reduced the chances of conception before Day 90 by a factor of 0.76. Also, the median calving to conception interval was significantly longer for cows calving twins (134 ± 4.5 days) than for cows delivering singletons (108 ± 0.8 days; P < 0.001). Moreover, in cows in which conception was successful, the risk of abortion was higher for cows that calved twins than for those calving singletons (13.7% vs. 10.3%, respectively; P = 0.01). Culling rates before Days 90, 120, and 300 postpartum were 15.6%, 16.1%, and 28.6%, and 7.6%, 8.7%, and 15.9% for cows calving twins and singletons, respectively. Cox regression analysis of the factors affecting the culling rate before Day 300 postpartum revealed a 1.41 times greater hazard ratio of culling for cows calving twins than cows calving singletons. Further, mean productive lifespan was almost 300 days shorter for primiparous twinners (N = 48, 602 ± 493 days) than for nontwinners (N = 2592; 899 ± 581 days; P < 0.01), and 200 days shorter for secundiparous twinners (N = 126, 914 ± 429 days) than for nontwinners undergoing at least two lactations (N = 1936, 1101 ± 522 days; P < 0.01). Kaplan-Meier survival curves for productive lifespan differed between primiparous twinners and non-twinners (P < 0.001), and between secundiparous twinners and nontwinners having at least two lactations (P = 0.017). Differences in culling patterns for twinners and nontwinners were not restricted to the subsequent lactation but continued as long as 800 days after first calving, strongly suggesting long-term negative effects of twinning. As an economic implication of our findings, we suggest that twin embryo reduction at the moment of pregnancy diagnosis could be a profitable strategy to cut twinning rates and abolish their detrimental effects on subsequent reproductive performance and productive lifespan.

Photoperiod length and the estrus synchronization protocol used before AI affect the twin pregnancy rate in dairy cattle.

This study addresses potential management risk factors affecting the incidence of twin pregnancies in high-producing dairy cows. Special attention was paid to the estrus synchronization protocol used before the AI resulting in pregnancy. Possible factors affecting the twin pregnancy rate were analyzed through binary logistic regression procedures on 2015 pregnant cows from July 2010 to July 2011. Twin pregnancy was recorded in 361 of the 2015 pregnancy diagnoses made (17.9%). Twin pregnancy rates differed among herds (P < 0.001) and ranged from 12.4% to 23.9%. Based on the odds ratios, the risk of twin pregnancy was reduced by factors of 0.65 or 0.71 when AI was performed during the warm season or an increasing photoperiod, respectively and increased by a factor of 1.11 for each unit increase in lactation number; by factors of 4.57 or 6.33 in cows that received a progesterone-releasing intravaginal device (PRID) plus 500 or 750 IU of equine chorionic gonadotropin (eCG) 28 days before the pregnancy AI, respectively; by a factor of 2.39 in cows with an ovarian cyst diagnosed in the 14 days prior to AI and treated with prostaglandins (PG); by factors of 1.94 or 3.91 in cows that received two PG doses during the 14 days prior to AI or cows that following failed PRID treatment had received PG started over the 28 days prior to AI, respectively; and by a factor of 2.58 in cows that had previously delivered twins compared to cows delivering singletons. Our results indicate that cow factors, such as lactation number and previous twining, as well as environmental factors, such as photoperiod and season and management related to synchronization protocols affect significantly the incidence of twin pregnancies.

Clinical implications of induced twin reduction in dairy cattle.

Embryo reduction may prevent the negative effects of twinning in dairy cattle; however, the technique may carry an additional risk of pregnancy loss. The aim of this study was to evaluate the effect on pregnancy maintenance of embryo reduction by manual amnion rupture in unilateral and bilateral twin pregnant cows. A secondary objective was to examine the dynamics of endocrine factors following the treatment. On Day 35-41 of gestation 55 cows bearing two live twin embryos (28 bilateral, 27 unilateral) were randomly assigned to a twin reduction group (n = 27; cows fitted with a progesterone releasing intra-vaginal device for 21 days after manual amnion rupture) or control group (n = 28; untreated cows). Pregnancy loss before Day 90 was recorded in nine control and eleven twin reduction cows (32.1% vs 40.7%, respectively, p = 0.508). Logistic regression models indicated that laterality was the only variable significantly affecting pregnancy loss. The pregnancy loss risk was 8.7 times higher for unilateral than for bilateral twin pregnancies (59.3% vs 14.3%, respectively, P < 0.001) yet was similar in the unilateral control and unilateral twin reduction cows (62.3% vs 53.8%, respectively, P = 0.581). In contrast, four of 14 cows with bilateral twin pregnancies undergoing twin reduction lost their pregnancies while no losses were recorded in control cows with bilateral pregnancies (P = 0.049). A rise in plasma progesterone concentration was detected on the day following treatment in the twin reduction group and concentrations remained high within the first week of treatment. Plasma pregnancy-associated glycoprotein-1 (PAG-1) concentrations fell between Day 35-41 and Day 42-48, regardless of treatment. Our findings indicate that embryo reduction by manual amnion rupture did not carry an additional risk of pregnancy loss for unilateral twin pregnancies, whereas it increased the risk of pregnancy failure in bilateral twin pregnancies. However, benefits of preventing cows from delivering twins might also be considered when assessing the success of embryo reduction in bilateral twin pregnancies.

Does heat stress provoke the loss of a continuous layer of cortical granules beneath the plasma membrane during oocyte maturation?

The objective of the present study was to evaluate the influence of heat stress on bovine oocyte maturation. Both nuclear stage and distribution of cortical granules (CG) were simultaneously evaluated in each oocyte. Oocyte overmaturation under standard conditions of culture was also evaluated. For this purpose, logistic regression procedures were used to evaluate possible effects of factors such as heat stress, overmaturation, replicate, CG distribution and metaphase II (MII) morphology on oocyte maturation. Based on the odds ratio, oocytes on heat stressed (HSO) and overmaturated (OMO) oocyte group were, respectively, 14.5 and 5.4 times more likely to show anomalous MII morphology than those matured under control conditions (CO). The likelihood for an oocyte of showing the CG distribution pattern IV (aging oocyte) was 6.3 and 9.3 times higher for HSO and OMO groups, respectively, than for the CO group. The risk of undergoing anomalous oocyte maturation, considering both nuclear stage and distribution of CG was 17.1 and 18 times greater in oocytes cultured in HSO and OMO groups, respectively, than those in the CO group. In conclusion, heat stress proved to be valuable in aging oocytes. Heat stress advanced age for nuclear and cytoplasmic processes in a similar form to that of oocyte overmaturation.