Effect of prepartum dietary energy sources on productive and reproductive performance in Nili Ravi buffaloes

Feeding of dietary energy sources has been extensively studied in dairy cows but not well described in dairy buffaloes. The objective of this study was to evaluate the effect of prepartum dietary energy sources on productive and reproductive performance in Nili Ravi buffaloes (n = 21). The buffaloes were offered isocaloric (1.55 Mcal/kg DM NE_L (net energy for lactation)) glucogenic (GD), lipogenic (LD), and mixed diet (MD) during 63 days prepartum and maintained (1.27 Mcal/kg DM NE_L) at lactation diet (LCD) during 14 weeks postpartum. Effects of dietary energy sources and week on animals were analyzed with the mixed model. The DMI, BCS, and body weights remained similar during the pre- and postpartum periods. The prepartum diets did not affect birth weight, blood metabolites, milk yield, and composition. The GD tended to early uterine involution, more follicle numbers, and early follicle formation. The prepartum feeding of dietary energy source had a similar effect on first estrus expression, days open, conception rate, pregnancy rate, and calving interval. So, it could be concluded that prepartum feeding of an isocaloric dietary energy source had a similar effect on the performance of buffaloes.

Feeding behavior in relation to ovarian cyclicity in cows with no or a short dry period

The objective of this study was to investigate relations between feeding behavior (FB) variables focusing on intake of the basal ration during 3 wk prepartum until 3 wk postpartum, and postpartum onset of luteal activity (OLA) in dairy cows subjected to no (0-d) or a short (30-d) dry period (DP). Feeding behavior of the basal ration intake (concentrate intake excluded) was continuously recorded by computerized feeders for 123 dairy cows and analyzed from 3 wk prepartum to 3 wk postpartum. Cows were subjected to a DP length: 0-d DP (n = 81), or 30-d DP (n = 42). Milk progesterone concentration was determined 3 times per week until 100 DIM to determine OLA, which was classified as early OLA (<21 DIM) and late OLA (≥21 DIM). Relations between FB and OLA class were analyzed using mixed models. During 3 wk prepartum, FB differed between parity class (parity 2 or ≥3 after calving). Cows with a 30-d DP prepartum, regardless of their OLA class, had more visits per meal, higher meal duration, total meal time, total daily feeding time, and lower feed intake and feeding rate compared with cows with 0-d DP. During the first 2 d postpartum, cows with OLA <21 had more visits per day and visits per meal compared with cows with OLA ≥21. During the first 3 wk postpartum, cows within the 30-d DP group with OLA <21 had greater meal size, feed intake, and feeding rate compared with cows with OLA ≥21 of this group. Cows within the 0-d DP group with OLA <21 had higher meal duration, total daily meal time, total daily feeding time, and meal size, but a lower feeding rate compared with cows with OLA ≥21 of this group. Concluding from the current study, cows with OLA <21 had a postpartum FB that reflected a cow with faster recovery from parturition and better adaptation to onset of lactation compared with OLA ≥21. No or a short DP affected prepartum FB, suggesting that prepartum management affects FB. This study provides evidence of different FB between cows with different timing of resumption of ovarian cyclicity.

The impact of the COVID-19 pandemic and behavioral restrictions on electricity consumption and the daily demand curve in Turkey

The rapid spread of COVID-19 has severely impacted many sectors, including the electricity sector. The reliability of the electricity sector is critical to the economy, health, and welfare of society; therefore, supply and demand need to be balanced in real-time, and the impact of unexpected factors should be analyzed. During the pandemic, behavioral restrictions such as lockdowns, closure of factories, schools, and shopping malls, and changing habits, such as shifted work and leisure hours at home, significantly affected the demand structure. In this research, the restrictions and their corresponding timing are classified and mapped with the Turkish electricity demand data to analyze the estimated impact of the restrictions on total demand and daily demand profile. A modulated Fourier Series Expansion evaluates deviations from normal conditions in the aggregate demand and the daily consumption profile. The aggregate demand shows a significant decrease in the early phase of the pandemic, during the period March-June 2020. The shape of the daily demand curve is analyzed to estimate how much demand shifted from daytime to night-time. A population-based restriction index is proposed to analyze the relationship between the strength and coverage of the restrictions and the total demand. The persistency of the changes in the daily demand curve in the post-contingency period is analyzed. These findings imply that new scheduling approaches for daily and weekly loads are required to avoid supply-demand mismatches in the future. The long-term policy implications for the energy transition and lessons learned from the COVID-19 pandemic experience are also presented.

Short communication: Variance and autocorrelation of deviations in daily milk yield are related with clinical mastitis in dairy cows

Daily milk production, and fluctuations therein, can provide information on health and resilience of dairy cows. We studied variance and autocorrelation of deviations in daily milk yield in relation to the occurrence of clinical mastitis (no, early or later in lactation). Individual lactation curves were fitted to 305-d lactations of 414 dairy cows using quantile regression. Log-transformed variance (lnVar) and autocorrelation of the quantile residuals of daily milk yield (predicted - observed) were evaluated for intervals until 30 and until 305 days in milk (DIM). Cows were classified as having no mastitis (n = 249), early mastitis that first occurred before 30 DIM (n = 29); or later mastitis (n = 136). Subsequently, linear models were used to assess effects of mastitis and parity class (primiparous or multiparous) on lnVar and autocorrelations; and logistic regression analyses were performed to predict mastitis from lnVar or autocorrelation and parity. From 10 to 30 DIM, lnVar was greater for cows with early mastitis than for cows with no or late mastitis, and autocorrelation tended to be lower for cows with early mastitis than for cows with no mastitis. The lnVar and autocorrelation from 10 to 30 DIM were not predictive of late mastitis. From 10 to 305 DIM, lnVar was greater and autocorrelation was lower for both cows with early and late mastitis than for cows with no mastitis; and both were predictive of having mastitis in the 305-d lactation. Primiparous cows had lower lnVar than multiparous cows. In cows without mastitis, autocorrelation values were positively correlated with lnVar. Results confirm that increased lnVar is associated with clinical mastitis.

Effects of extended voluntary waiting period from calving until first insemination on body condition, milk yield, and lactation persistency

A 1-yr calving interval (CInt) is usually associated with maximized milk output, due to the calving-related peak in milk yield. Extending CInt could benefit cow health and production efficiency due to fewer transition periods per unit of time. Extending CInt can affect lactation performance by fewer days dry per year, delayed pregnancy effect on milk yield, and greater milk solid yield in late lactation. This study first investigated the effects of 3 different voluntary waiting periods (VWP) from calving until first insemination on body weight, body condition, milk yield, and lactation persistency. Second, individual cow characteristics in early lactation were identified that contributed to milk yield and persistency of cows with different VWP. Holstein-Friesian dairy cows (n = 154) within 1 herd were blocked for parity, calving season, and expected milk yield. Cows were randomly assigned within the blocks to 1 of 3 VWP (50, 125, or 200 d: VWP50, VWP125, or VWP200, respectively) and monitored through 1 complete lactation and the first 6 wk of the subsequent lactation, or until culling. Minimum and mean CInt (384 vs. 452 vs. 501 d for VWP50 vs. VWP125 vs. VWP200) increased with increasing VWP, but maximum CInt was equal for the 3 VWP. Fat- and protein-corrected milk yield (FPCM) was analyzed weekly. Milk yield and FPCM were also expressed per day of CInt, to compare yields of cows with different VWP. Persistency was determined between d 100 and d 200 of the lactation, as well as between d 100 and dry-off. Values are presented as least squares means ± standard error of the mean. During the first 44 wk of lactation, VWP did not affect FPCM yield in both primiparous and multiparous cows. The VWP did not affect milk yield per day of CInt. The VWP did not affect FPCM yield per day of calving interval for primiparous cows. Multiparous cows in VWP125 had FPCM yield per day of CInt similar to that of VWP50. Multiparous cows in VWP200 had lower FPCM yield per day of CInt compared with VWP50 (27.2 vs. 30.4 kg/d). During the last 6 wk before dry-off, cows in VWP125 had lower yield compared with cows in VWP50, which could benefit their udder health in the dry period and after calving. Persistency was better for cows in VWP200 compared with cows in VWP50 (-0.05 vs. -0.07 kg/d). Body weight was not different among VWP groups. Multiparous cows in VWP200 had a higher body condition score in the last 3 mo before dry-off and the first 6 wk of the next lactation, compared with multiparous cows in VWP125 and VWP50. The VWP could be extended from 50 d to 125 d without an effect on daily yield per day of calving interval. Extending VWP until 200 d for primiparous cows did not affect their daily milk yield, but multiparous cows with a 200-d VWP had a reduced milk yield per day of calving interval and an increased body condition in late lactation and the subsequent lactation, compared with multiparous cows with a 50-d VWP.

Evaluation of customized dry-period strategies in dairy cows

Shortening or omitting the dry period to improve the energy balance in early lactation have the trade-offs of reduction in milk production and loss of opportunity for dry-cow therapy (DCT; i.e., intramammary antibiotic use at dry-off). Customized dry-period strategies (i.e., deciding upon DCT and dry-period length per cow) could mitigate negative effects of short or no dry periods on milk production and udder health and simultaneously retain benefits from improved energy balance and fertility. In this study, we evaluated 3 decision trees to customize dry-period strategies for individual cows. In the control tree (CT), all cows had a 60-d dry period, with DCT if somatic cell count (SCC) was >150,000 cells/mL before dry-off. In decision tree 1 (T1), parity 1 and parity >1 cows were assigned DCT if SCC was ≥150,000 cells/mL and SCC ≥50,000 cells/mL, respectively; whereas in decision tree 2 (T2), the threshold for DCT was SCC ≥200,000 cells/mL for all animals. In T1 and T2, cows with DCT were assigned a 60-d dry period, whereas cows without DCT were assigned a 30-d or 0-d dry period if their milk production remained >12 kg/d at 67 and 37 d before calving, respectively. Cows were monitored from 8 wk before to 14 wk after calving. Milk production and composition, SCC, body condition score, body weight, and occurrence of treatment for disease (related to calving and start of lactation) were compared between CT (n = 61 cows), T1 (n = 59 cows), and T2 (n = 63 cows). Effects of decision trees (CT, T1, T2) and of dry-period strategies (60-d dry with or without antibiotics, 30-d dry, or 0-d dry) on measured variables were analyzed separately with mixed models, effects on udder-health status with a logistic regression, and occurrence of treatment for diseases with a Pearson chi-squared test. In T1, 36% of cows qualified for 30-d and 2% for 0-d dry periods, whereas in T2 this was 51% and 30% for 30-d and 0-d dry periods, respectively. Compared with CT, cows in T1 and T2 on average produced more milk in the 8 wk before calving (0.2 vs. 3.9 vs. 7.1 kg/d in CT vs. T1 vs. T2), and less in the 14 wk after calving (40.0 vs. 37.0 vs. 35.2 kg/d in CT vs. T1 vs. T2). There was no difference in udder-health status in the transition period among decision trees. In the first 14 wk after calving, recovery of body weight was greater for T2 than CT and T1. Overall, 30-d and 0-d dry periods reduced milk revenues, but this might be financially compensated by improved cow health with customized dry-period strategies.

Fertility and milk production on commercial dairy farms with customized lactation lengths

Drying-off, calving, and start of lactation are critical transition events for a dairy cow. As a consequence, most animal health issues occur during these periods. By extending the voluntary waiting period for first insemination after calving, calving interval (CInt) can be extended, with possible positive effects for fertility and health. Some cows might be better suited for an extended CInt than others, due to differences in milk yield level, lactation persistency, or health status, which would justify a customized CInt based on individual cow characteristics. This study aims to investigate 13 farms with customized CInt, with respect to calving to first service interval (CFSI), accomplished CInt, services per conception (SC), conception rate at first artificial insemination (CR1AI), peak yield, lactation persistency, 305-d yield, and effective lactation yield. In total, 4,858 complete lactations of Holstein Friesian cows between 2014 and 2019 from the 13 farms were grouped by parity (1 or 2+) and CFSI (CFSI class; CFSI-1 < 84; 84 ≤ CFSI-2 < 140; 140 ≤ CFSI-3 < 196; 196 ≤ CFSI-4 < 252, CFSI-5 ≥ 252 d) or CInt (CInt class; CInt-1 < 364; 364 ≤ CInt-2 < 420; 420 ≤ CInt-3 < 476; 476 ≤ CInt-4 < 532, CInt-5 ≥ 532 d). Cow inseminations, available for 11 out of 13 farms (3,597 complete lactations), were grouped by parity (1 and 2+) and CFSI class or CInt class. The fertility and milk production characteristics were analyzed with generalized and general linear mixed models. The CFSI class was not associated with SC, but extended CInt class was associated with increased SC (CInt-1-5; 1.11-3.70 SC). More than 50% of cows in the CFSI class <84 d ended up in longer than expected CInt (>364 d), showing that these cows were not able to conceive for the desired CInt. More than 50% of cows in CInt classes 3 and higher (CInt ≥ 420 d) had an earlier first insemination before successful insemination (CFSI class 1; <196 d), showing that these extended CInt classes consisted of both cows with an extended waiting period for first insemination and cows that failed to conceive at earlier insemination(s). On most farms, lactation persistency was greatest in CInt class 1 (<364 d), probably related to the low peak yield in this class. When this shortest CInt class was excluded, persistency increased with extended CInt classes on most farms. Although at the majority of farms 305-d yield was greater in CInt ≥ 532 d, effective lactation yield at most farms was greatest in CInt from 364 to 531 d, especially for multiparous cows. Based on the results of this study, a CInt between 364 and 531 days seems most optimal for milk production, when high-yielding cows were selected.

Treatment and Outcome of Patients with Uterine Carcinosarcoma in a Comprehensive Cancer Network

Aim

To determine clinical characteristics, treatment modalities and survival of uterine carcinosarcoma (UCS).

Methods

Data on treatment of UCS patients in the Comprehensive Cancer Network south region in the Netherlands between 2004 and 2014 were retrospectively evaluated.

Results

Data of 62 patients with UCS were retrieved. Mean age at diagnosis was 69.2 years (45–95 years). Data of six patients were excluded because they did not receive any treatment. Of the 56 patients included in this study, 57.1% presented with early-stage (FIGO I–II) disease and 42.9% with late-stage (FIGO III–IV) disease. 46.9% of the patients with FIGO early-stage disease received only surgical treatment, whereas 9.4% received adjuvant chemotherapy and 43.8% received adjuvant radiotherapy. Median DFS in patients with early-stage disease was 47.0 months (17.5–72.0). Adjuvant therapy did not seem to alter prognosis (p = 0.261). 16.7% of the patients with late-stage disease received only surgical treatment, 12.5% received only chemotherapy, whereas 50% received adjuvant chemotherapy and 20.8% adjuvant radiotherapy after surgery. Median DFS in late-stage disease was 8.5 months (2.5–23.5). Adjuvant therapy did not seem to alter prognosis (p = 0.30).

Conclusion

UCS with both FIGO stages I–II and III–IV has a dismal prognosis. The addition of adjuvant treatment did not seem to increase survival.

New research criteria for the diagnosis of Alzheimer's disease applied in a memory clinic population

BACKGROUND

In the newly proposed research criteria for Alzheimer's disease (AD), patients are defined as having memory dysfunction in addition to either hippocampal atrophy or an abnormal cerebrospinal fluid (CSF) profile. This study applies the criteria in a memory clinic population, using clinical criteria as the reference criterion.

METHODS

138 AD patients, 145 nondemented subjects, 78 patients with other dementias and 91 patients with mild cognitive impairment (MCI) were included. Dichotomized medial temporal lobe atrophy (MTA) score on MRI and dichotomized CSF profiles (based on beta-amyloid1-42, tau and phosphorylated tau at threonine 181 levels) were used in combination with an episodic memory test to assess sensitivity, specificity and likelihood ratios (LR) of the newly proposed criteria and their components separately.

RESULTS

We found specificities of 95 and 49% for comparison with nondemented subjects and other demented patients, respectively, with a sensitivity of 86% for AD. Specificity was highest (100 and 77%, respectively, LR+ = 48) when both MTA score and CSF profile were abnormal in addition to the episodic memory test, at the cost of a low sensitivity (48%).

CONCLUSION

The newly proposed research criteria for AD yield a good specificity for comparison with nondemented subjects. When the type of dementia is clinically doubted, however, at least two supportive features should be considered (i.e. abnormal MTA score and CSF profile) in addition to memory impairment as core diagnostic criterion.

Amyloid-β(1–42), Total Tau, and Phosphorylated Tau as Cerebrospinal Fluid Biomarkers for the Diagnosis of Alzheimer Disease

Background: To improve ante mortem diagnostic accuracy of Alzheimer disease (AD), measurement of the biomarkers amyloid-β(1–42) (Aβ42), total tau (Tau), and tau phosphorylated at threonine181 (pTau) in cerebrospinal fluid (CSF) has been proposed. We have used these markers and evaluated their performance.

Methods: From January 2001 to January 2007, we assessed Aβ42, Tau, and pTau by commercial ELISAs in CSF from 248 consecutive AD patients and 131 patients with subjective memory complaints attending our outpatient memory clinic. Diagnoses were made blind to the results of the biomarker assays. We assessed sensitivity and specificity and analyzed trends over time.

Results: Interassay CVs from analysis of pools of surplus CSF specimens were mean 11.3% (SD 4.9%) for Aβ42; 9.3% (1.5%) for Tau, and 9.4% (2.5%) for pTau, respectively (n = 7–18). To achieve 85% sensitivity, cutoff values were 550 (95% CI 531–570) ng/L for Aβ42; 375 (325–405) ng/L for Tau, and 52 (48–56) ng/L for pTau. Corresponding specificities were 83% (95% CI 76%–89%) for Aβ42, 78% (70%–85%) for Tau, and 68% (60%–77%) for pTau. Logistic regression to investigate the simultaneous impact of the 3 CSF biomarkers on the diagnosis yielded a sensitivity of 93.5% and specificity of 82.7%, at a discrimination line of Aβ42 = 373 + 0.82 × Tau. The area under the ROC curves of Tau and pTau showed significant fluctuation over time.

Conclusions: CSF biomarkers Aβ42 and Tau can be used as a diagnostic aid in AD. pTau did not have additional value over these 2 markers. Cutoff values, sensitivities, specificities, and discrimination lines depend on the patient groups studied and laboratory experience.

Never injected, but hepatitis C virus-infected: a study among self-declared never-injecting drug users from the Amsterdam Cohort Studies

The aim of this study was to gain insight in transmission routes of hepatitis C virus (HCV) infection among never-injecting drug users (DU) by studying, incidence, prevalence, determinants and molecular epidemiology of HCV infection. From the Amsterdam Cohort Studies among DU, 352 never-injecting DU were longitudinally tested for HCV antibodies. Logistic regression was used to identify factors associated with antibody prevalence. Part of HCV NS5B was sequenced to determine HCV genotype and for phylogenetic analyses, in which sequences were compared with those from injecting DU. HCV antibody prevalence was 6.3% and HCV incidence was 0.49/1000 PY. HIV-positive status, female sex and starting injection drug use during follow-up (a putative marker of past injection drug use), were independently associated with HCV prevalence. The main genotypes found were genotype 3a (50%) and 1a (30%). Phylogenetic analysis revealed that HCV strains in never-injecting DU did not cluster together and did not differ from HCV strains circulating in injecting DU. We found a higher HCV prevalence in never-injecting DU than in the general population. Phylogenetic analysis shows a strong link with the injecting DU population. The increased risk could be related to underreporting of injecting drug use or to household or sexual transmission from injectors to noninjectors. Our findings stress the need for HCV testing of DU who report never injecting, especially given the potential to treat HCV infection effectively.

Interferon-beta bioactivity measurement in multiple sclerosis: feasibility for routine clinical practice

BACKGROUND

Neutralising antibodies (NAb) to interferon beta (IFN beta) are associated with a reduced bioactivity and efficacy of IFN beta in multiple sclerosis (MS). Unclear is how to apply IFN beta bioactivity measurements (quantification of Myxovirus resistance protein A (MxA) mRNA) in clinical practice.

OBJECTIVES

To evaluate value and feasibility of IFN beta bioactivity measurement with a single MxA mRNA measurement for screening and a second measurement before and after IFN beta administration for definite confirmation of IFN beta bioactivity status.

METHODS

In 79 MS patients MxA mRNA expression was determined 4 hours after IFN beta administration. If inadequate, MxA mRNA expression testing was repeated 3 months afterwards, comparing post- and pre injection samples to determine whether IFNb bioactivity was persistently lacking. MxA mRNA expression was compared to NA beta titres, determined by the cytopathic effect assay (CPE).

RESULTS

NAb titres correlated significantly with MxA mRNA expression and MxA mRNA induction. Of all screened patients, only one patient had adequate MxA mRNA expression and high NAb titres simultaneously. Of the biological non-responders at second measurement (21/55), 17 (81%) were high-titre NAb positive, 1 (5%) was low-titre NAb positive and 3 (14%) were NAb negative. Without considering the pre-injection measurement, two more NAb negative patients would have tested negative for IFN beta bioactivity, emphasizing the need of a pre-injection sample.

CONCLUSIONS

Our data suggest that for IFN beta bioactivity screening a single post-injection measurement seems reasonable. However, MxA induction measurement based on both pre- and post-IFN beta injection samples at second measurement is somewhat more precise in determining ultimate IFN beta bioactivity status.

Antibiotic treatment is associated with reduced risk of a subsequent exacerbation in obstructive lung disease: an historical population based cohort study

OBJECTIVES

The risk of a subsequent exacerbation after treatment of an exacerbation with oral corticosteroids without (OS) or with (OSA) antibiotics was evaluated in a historical population based cohort study comprising patients using maintenance medication for obstructive lung disease.

METHODS

The Pharmo database includes drug dispensing records of more than 2 million subjects in The Netherlands. Eligible were patients >or=50 years who in 2003 were dispensed >or=2 prescriptions of daily used inhaled beta(2) agonists, anticholinergics and/or corticosteroids, and experienced at least one exacerbation before 1 January 2006. Exacerbation was defined as a prescription of OS or OSA. The times to the second and third exacerbations were compared using Kaplan-Meier survival analysis. Independent determinants of new exacerbations were identified using multivariable Cox recurrent event survival analysis.

RESULTS

Of 49,599 patients using maintenance medication, 18 928 had at least one exacerbation; in 52%, antibiotics had been added. The OS and OSA groups were comparable for potential confounding factors. Median time to the second exacerbation was 321 days in the OS group and 418 days in the OSA group (p<0.001); and between the second and third exacerbation 127 vs 240 days (p<0.001). The protective effect of OSA was most pronounced during the first 3 months following treatment (hazard ratio (HR) 0.62; 99% CI 0.60 to 0.65). In the OSA group, mortality during follow-up was lower (HR 0.82; 99% CI 0.66 to 0.98).

CONCLUSION

Treatment with antibiotics in addition to oral corticosteroids was associated with a longer time to the next exacerbation, and a decreased risk of developing a new exacerbation.

CSF biomarker levels in early and late onset Alzheimer's disease

OBJECTIVE

To compare CSF levels of beta-amyloid 1-42 (Abeta(1-42)), total tau (tau) and tau phosphorylated at threonine 181 (ptau-181) between AD patients and controls according to age.

METHODS

248 AD patients (48% men) and 127 controls (51% men, 22 volunteers and 105 subjective complainers) underwent lumbar puncture. Both patients and controls were divided into a young (<65 years) and old (>or=65 years) group.

RESULTS

All three biomarkers showed main effects of diagnosis (p<0.001). There was an interaction between diagnosis and age for all three biomarkers (p<0.05), as old controls had lower Abeta(1-42) and higher (p)tau than young controls (Abeta(1-42) 699+/-250 versus 866+/-191pg/ml, tau 408+/-245 versus 243+/-102pg/ml, ptau-181 60+/-28 versus 42+/-15pg/ml), but there was no difference according to age among AD patients (Abeta(1-42) 451+/-178 versus 425+/-146pg/ml, tau 741+/-460 versus 798+/-467pg/ml, ptau-181 91+/-42 versus 91+/-41pg/ml).

CONCLUSION

We found that the older control group had lower Abeta(1-42) and higher (p)tau compared to the younger control group. This suggests that older individuals may have AD pathology, even in the absence of objective cognitive impairment.

Comparison of two consecutive fat-rich and carbohydrate-rich meals on postprandial myeloperoxidase response in women with and without type 2 diabetes mellitus

Patients with type 2 diabetes mellitus (DM2) have an increased risk of cardiovascular disease (CVD). Myeloperoxidase (MPO), expressed in leukocytes and released upon activation, is associated with CVD and endothelial dysfunction. Postprandial leukocyte recruitment and activation with subsequent MPO release may contribute to atherosclerosis and CVD. We hypothesized that MPO may increase in the postprandial state because of postprandial leukocyte recruitment and/or activation, especially in subjects with DM2. One hundred postmenopausal women, aged 50 to 65 years (66 with normal glucose metabolism [NGM] and 34 with DM2), received 2 consecutive fat-rich meals and 2 consecutive carbohydrate-rich meals on separate occasions. Blood samples were taken before (t = 0) and at 2, 4, and 8 hours after breakfast; lunch was given at t = 4. Plasma MPO concentration was measured by sandwich enzyme-linked immunosorbent assay. The number of leukocytes in fasting blood samples was higher in DM2 compared with NGM (6.1 +/- 1.4 and 5.4 +/- 1.2 x 10(9)/L, respectively; P < .05). Baseline MPO concentration did not significantly differ between NGM and DM2 (51.4 +/- 12.9 and 54.5 +/- 18.4 mug/L, respectively; P = .39). Baseline MPO was positively associated with leukocytes (r = 0.20, P < .05) and inversely associated with high-density lipoprotein cholesterol (r = -0.22, P < .05). Leukocytes increased from 5.0 +/- 1.5 to 6.1 +/- 1.5 x 10(9)/L and from 5.8 +/- 1.4 to 6.6 +/- 1.4 x 10(9)/L in NGM and DM2, respectively (both P < .01), after the fat-rich meals. In contrast to our hypothesized increase in MPO, we found a significant decrease in MPO in NGM (both meal types) and DM2 (fat-rich meals only). Our findings provide no support to our initial hypothesis that meal-induced release of MPO might be a mechanism that contributes to CVD risk.

Cognitive impairment in Alzheimer's disease is modified by APOE genotype

AIM

We examined whether impairment in specific cognitive domains in Alzheimer's disease (AD) differed according to APOE genotype and age at onset.

METHODS

Cognitive functions of 229 consecutive AD patients were assessed using Visual Association Test (VAT), Memory Impairment Screen+ (MIS+), VAT object naming, fluency test and Trail Making Test (TMT). Dementia severity was assessed using MMSE. ANOVAs were performed with APOE genotype and age at onset as independent variables and sex, education and MMSE as covariates.

RESULTS

28% of patients were APOE epsilon4-negative, 58% heterozygous and 14% homozygous. A significant association between APOE genotype and VAT and MIS+ was found when correcting for sex and education. An interaction effect between APOE genotype and age at onset on VAT and VAT object naming was found, with young carriers performing worse than young noncarriers. By contrast, when additionally correcting for MMSE, a significant association between APOE genotype and VAT object naming, TMT-A and TMT-B was found, with noncarriers performing worse than carriers.

CONCLUSION

Memory was more impaired among APOE epsilon4 carriers than among noncarriers. By contrast, naming, executive functions and mental speed were more impaired among APOE epsilon4 noncarriers. This suggests that the APOE genotype modifies the clinical phenotype in terms of cognitive impairment in AD.

[Hepatitis C in the Netherlands: sparse data on the current prevalence and the necessity for epidemiological studies and innovative methods for detecting infected individuals]

Hepatitis C is a blood-borne virus infection with an estimated 180 million infected individuals worldwide. Hepatitis C virus (HCV) infection may lead to liver failure and cancer of the liver. In 2004, in view of the improved treatment options, the Dutch Health Council again recommended that the groups at risk of HCV infection should be tracked down and informed, and that epidemiological studies should be conducted. Currently, there are few data on the prevalence of HCV infection in the Netherlands. HCV risk groups are (former) injecting drug users, haemodialysis patients and haemophiliacs, people treated with blood or blood products before 1992, people who have undergone certain invasive or medical procedures with insufficiently sterilised instruments, household contacts and partners of HCV-infected individuals and children born to HCV-infected mothers. Insight into the epidemiology of HCV infection in the Netherlands is necessary so that reliable estimates of the magnitude of hepatitis C as a public health problem can be made. Several projects for the detection of HCV infected individuals and epidemiological studies have started in 2007.

Contribution of metabolic syndrome components to cognition in older individuals

OBJECTIVE

Recent evidence suggests that the metabolic syndrome and inflammation affect cognitive decline in old age and that they reinforce each other. However, it is not known what the roles of the individual components of the metabolic syndrome on cognition are.

RESEARCH DESIGN AND METHODS

The sample consisted of 1,183 participants in the Longitudinal Aging Study Amsterdam who were aged 65-88 years. Metabolic syndrome (U.S. National Cholesterol Education Program definition) and its individual components and the inflammatory markers C-reactive protein (CRP) and alpha1-antichymotrypsin (ACT) were assessed. Cognitive assessments included general cognition (Mini-Mental State Examination), memory (verbal learning test), fluid intelligence (Raven's Matrices), and information processing speed (coding task).

RESULTS

Of the sample, 36.3% had metabolic syndrome. Metabolic syndrome was significantly associated with all cognitive measures (P < 0.05). Of the individual components, hyperglycemia was most strongly and significantly associated with cognitive function (multivariate adjusted models; B values, indicating differences in scores between both groups, ranging from -0.38 to -1.21). There was a significant interaction between metabolic syndrome and inflammation on cognition (P < 0.01-0.09). Metabolic syndrome was negatively associated with cognition in subjects with high inflammation (highest tertile for both CRP and ACT; B values ranging from -0.86 to -1.94, P < 0.05), whereas an association was absent in subjects with low inflammation (B values ranging from -0.10 to -0.70).

CONCLUSIONS

Subjects with metabolic syndrome showed poorer cognitive performance than subjects without metabolic syndrome, especially those with high levels of inflammation. Hyperglycemia was the main contributor of the association of metabolic syndrome with cognition.

Longitudinal changes of CSF biomarkers in memory clinic patients

OBJECTIVE

In Alzheimer disease (AD), longitudinal changes of beta-amyloid(1-42) (Abeta(1-42)), tau, and phosphorylated tau at threonine 181 (ptau-181) in CSF have been reported in small studies only. We evaluated the natural course of CSF biomarkers in patients with AD, subjective complaints, and mild cognitive impairment (MCI).

METHODS

One hundred five patients (50 AD, 38 MCI, 17 subjective complaints) underwent two lumbar punctures, with a mean interval of 21 +/- 9 months. CSF levels of Abeta(1-42), tau, and ptau-181 were measured.

RESULTS

CSF Abeta(1-42) and tau levels showed main effects for both diagnosis and time (all p < 0.05), with average increases of 47 +/- 72 and 49 +/- 143 pg/mL. The interaction terms were not significant, which implies a similar time effect for all diagnostic groups. CSF ptau-181 levels showed a main effect for diagnosis (p = 0.01) but not for time (p = 0.27, increase of 1.0 +/- 12 pg/mL).

CONCLUSION

Levels of CSF beta-amyloid(1-42) and tau but not phosphorylated tau at threonine 181 increased over time in this memory clinic patient cohort with comparable change in all diagnostic groups. The cross-sectional difference between diagnostic groups, however, exceeded by far the longitudinal changes within individuals, suggesting that these biomarkers are not sensitive as markers of disease progression.

fMRI evidence for both generalized and specialized components of attentional control

A central question in the study of selective attention is whether top-down attentional control mechanisms are generalized or specialized for the type of information that is to be attended. The current study examined this question using a voluntary orienting task that cued observers to attend to either one of two locations or to one of two colors. Location (spatial) and color (nonspatial) conditions were presented either randomly intermixed within the same block of trials or in separate blocks. Functional magnetic resonance imaging revealed that directing attention to a location or to a color activated a network of overlapping dorsal frontal and parietal areas, previously implicated in attentional control. The pattern of observed overlap was not affected by the intermixed versus blocked presentation of location and color conditions. Although portions of the frontal-parietal network were more active in response to location cues than to color cues, a secondary analysis also revealed that medial dorsal frontal and parietal cortex were specifically engaged in shifting visual attention regardless of the cued dimension (location or color). Together, the present results support the conclusion that attentional control is the combination of a generalized network that works in concert with subregions of the frontoparietal network that are highly specialized for directing attention based on the content of the to-be-attended information.

Stability of soluble adhesion molecules, selectins, and C-reactive protein at various temperatures: implications for epidemiological and large-scale clinical studies

BACKGROUND

We assessed the impact of sample storage conditions on soluble vascular cell adhesion molecules (sVCAM), soluble intracellular adhesion molecules (sICAM-1), soluble (s)E-selectin, C-reactive protein (CRP), and sP-selectin.

METHODS

Markers were measured by ELISA in venous blood from 10 healthy volunteers on aliquots stored as plasma or whole blood at 4, 21, or 30 degrees C for 1-5 days and after 1-5 freeze-thaw cycles. We compared results on these samples to results for samples processed immediately and stored at -80 degrees C. Statistical models assessed time-related effects and effects of postprocessing conditions.

RESULTS

Using an upper limit of 10% variation from baseline with P >0.05, we found that stability duration in plasma was 5 days for sVCAM-1 and sICAM-1 and at least 2 days for sE-selectin at 4, 21, and 30 degrees C and 5 days for CRP at 4 and 21 degrees C and 1 day at 30 degrees C. Stability duration in whole blood was 5 days for sVCAM-1 and sICAM-1 and at least 2 days for sE-selectin at 4, 21, and 30 degrees C and 5 days for CRP at 4 and 21 degrees C and 2 days at 30 degrees C. sP-selectin was not stable in plasma or whole blood. sICAM-1, sVCAM-1, CRP, and sE-selectin were stable after 5 freeze-thaw cycles.

CONCLUSIONS

sVCAM-1, sICAM-1, and CRP are stable in plasma or whole blood at 4 and 21 degrees C for at least 3 days and sE-selectin for 2 days. sP-selectin is not stable and therefore requires immediate assay.

Apolipoprotein E genotype influences presence and severity of delusions and aggressive behavior in Alzheimer disease

AIM

We investigated differences in the prevalence and severity of 10 neuropsychiatric and behavioral symptoms according to apolipoprotein E (APOE) genotype and dementia severity in Alzheimer disease (AD).

METHODS

Neuropsychiatric and behavioral symptoms of 110 AD patients were assessed using the Neuropsychatric Inventory. Dementia severity was assessed using the Mini Mental State Examination (MMSE).

RESULTS

There were 27 APOE-epsilon4-negative patients, 65 heterozygous patients and 18 homozygous patients. There was a significant association between the number of APOE epsilon4 alleles and prevalence and severity of neuropsychiatric and behavioral symptoms that was mainly attributable to delusions and agitation/aggression, which were more common and severer among homozygous APOE epsilon4 carriers. In addition, the presence of hallucinations, anxiety, apathy and aberrant motor behavior increased with deteriorating MMSE score, independently of APOE epsilon4 status.

CONCLUSIONS

The present study showed that the APOE epsilon4 genotype modifies neuropsychiatric and behavioral phenotype in AD. In particular, it was shown that delusions and agitation/aggression were more common and severer among homozygous APOE epsilon4 carriers than among heterozygous or APOE-epsilon4-negative patients.

Brain regions activated by endogenous preparatory set shifting as revealed by fMRI

An ongoing controversy concerns whether executive control mechanisms can actively reconfigure the cognitive system in preparation for switching to a new task set. To address this question, we recorded brain activity from 14 healthy participants, using event-related functional magnetic resonance imaging, while they performed a cued attention task. Critically, in any particular trial, the cued task set was either the same as that in the previous trial or switched. As was hypothesized, cue-related, switch-specific preparatory activity was observed in a network of dorsal frontal and parietal brain areas that are typically associated with cognitive control processes. Moreover, the magnitude of switch-specific preparatory activity varied with the number of possible task sets that could be presented in a given trial block. These findings provide compelling support for the existence of top-down, preparatory control processes that enable set switching. Furthermore, they demonstrate that global task structure is a critical determinant of whether switch-specific preparatory activity is observed.

Effects of stop-signal modality on the N2/P3 complex elicited in the stop-signal paradigm

The principal aim of the present study was to clarify how stop-signal modality affected the speed and efficacy of stopping, using ERP components as converging measures of stop processes. Both performance and ERP latency findings suggested faster processing of stop signals in the auditory than visual version of the stop task. The effects of successful versus unsuccessful stopping on the amplitude and topography of N2/P3 components elicited by the stop signals appeared to be largely independent of the modality of the stop signals. Stop signals elicited a fronto-central N2 that was much larger on unsuccessful than successful stop trials in stimulus-locked waveforms. N2 was followed by a P3 component that showed a fronto-central distribution on successful stop trials. P3 elicited on unsuccessful stop trials showed a posterior-parietal focus, but this topography was manifested more clearly in response-locked than stimulus-locked waveforms. A dipole source analyses confirmed these topographical differences of P3, and further showed that the location of the corresponding dipoles remained largely identical across the visual and auditory versions of the stop-signal task. Taken together, the present findings support the suggestion that ERP components in the stop task reflect endogenous aspects of stop-signal processing, such as effective inhibition of responses on successful stop trials and detection of errors on failed inhibition trials.

Dose-Finding Study of the Multitargeted Tyrosine Kinase Inhibitor SU6668 in Patients with Advanced Malignancies

PURPOSE

SU6668 is a tyrosine kinase inhibitor which targets platelet-derived growth factor receptor-beta, fibroblast growth factor receptor-1, vascular endothelial growth factor receptor-2, and KIT. We did a phase I study to define the maximum tolerated dose and to assess the pharmacokinetics of SU6668 administered orally thrice daily with food.

PATIENTS AND METHODS

Patients with histologically proven, advanced, and progressive solid tumors were included at a starting dose level of 400 mg/m2 thrice daily. The early onset of dose-limiting toxicities (DLT) required dose reductions to 100 and 200 mg/m2 thrice daily. Pharmacokinetics was done on days 1, 28, and 56.

RESULTS

Sixteen patients were included. Two of the first three patients developed DLTs, which consisted of grade 4 fatigue and grade 3 serositis-like pains. Six patients at dose level 100 mg/m2 thrice daily experienced no DLT. At dose level 200 mg/m2 thrice daily, two out of seven patients experienced DLTs consisting of grade 3 abdominal pain, grade 4 anorexia and grade 3 nausea/vomiting. Increasing doses resulted in a disproportional increase in area under the curve and C(max) (peak plasma concentration). Both variables, however, decreased significantly on days 28 and 56 compared with day 1 (P < 0.05). No objective responses were observed. Acute phase response, probably mediated by interleukin-6, was observed in serial blood samples.

CONCLUSIONS

The maximum tolerated dose of SU6668 given orally, thrice daily under fed conditions, is 100 mg/m2. Because of the low plasma levels reached at this dose level, the efficacy of SU6668 as a single agent is not to be expected.

Decrease of CD4+CD25+ T Cells in Peripheral Blood After Liver Transplantation: Association With Immunosuppression

CD25 (IL-2 receptor alpha-chain) marks a population of CD4-positive T cells with a suppressor phenotype. These CD4+CD25+ regulatory T cells can suppress both effector T cells and antigen-presenting cells and have been identified as a principle regulator of tolerance in experimental transplantation models. In the setting of human liver transplantation, however, little is known about the dynamics of these cells in relation to rejection, tolerance, and immunosuppression. In the current study we determined CD4+CD25+ T cell in blood of liver transplant recipients using flow cytometry and investigated a possible link with immunosuppressive therapies. Peripheral blood mononuclear cells (PBMC) of 27 liver transplant patients (pretransplantation and 12 months posttransplantation) and 16 healthy controls were included. We found that the percentages of CD25+ cells within the CD4 T-cell population was significantly reduced in more than two-thirds of patients 1 year after transplantation. Also the total percentage of CD4-positive T cells declined significantly within this period, making the absolute reduction of regulatory T cells after transplantation even more profound. Comparing PBMC samples of patients and healthy controls revealed an increased percentage of CD4+ T cells in the patients before transplantation, probably related to the chronic liver illness. The reduction in CD4+CD25+ T cells after transplantation was similar for different immunosuppression regiments. All patients, however, received calcineurin inhibitors, suggesting a possible suppressive effect of this therapy on regulatory T-cell levels in peripheral blood. Currently, assays for regulatory T-cell activity are used to further support this hypothesis.