Effects of homolactic bacterial inoculant on the performance of lactating dairy cows

The objective of this experiment was to determine the effect of applying a homofermentative bacterial inoculant to corn silage on the performance of dairy cows. After harvesting, corn forage was treated with nothing (CON) or with an inoculant containing a mixture of Lactococcus lactis, Lactobacillus plantarum, and Enterococcus faecium at 1.5 × 10⁵ cfu/g of fresh forage (MC; SiloSolve MC, Chr. Hansen A/S, Hørsholm, Denmark). After 186 d of storage in Ag-Bags (A Miller-St. Nazianz Inc., St. Nazianz, WI), silages were fed as part of a total mixed ration containing 55% concentrates, 10% alfalfa hay, and 35% CON or MC corn silage. Sixty early-lactation Holstein dairy cows (30 multiparous and 30 primiparous) housed in a freestall barn with Calan gates (American Calan Inc., Northwood, NH) were assigned to the dietary treatments from 20 to 100 d in milk. Silage inoculated with MC had a more homofermentative pattern evidenced by greater lactic acid concentration (3.83 vs. 4.48% of DM) and lower concentrations of acetic (2.34 vs. 1.68% of DM) and propionic (0.37 vs. 0.10% of DM) acids and ammonia (9.11 vs. 7.82% of N) for CON and MC, respectively. Dry matter intake (23.1 vs. 23.2 kg/d) did not differ among treatments, but the MC silage had greater apparent digestibility of DM (68.8 vs. 70.8%), which led to greater yields of milk (37.7 vs. 38.5 kg/d), fat-corrected milk (37.6 vs. 38.4 kg/d), milk fat (1.30 vs. 1.33 kg/d), and lactose (1.83 vs. 1.92 kg/d) for CON and MC cows, respectively. Milk from cows fed MC silage had higher lactose (4.86 vs. 4.93%), lower protein (2.93 vs. 2.83%), and similar contents of fat (3.47 vs. 3.44%) compared with CON cows. Feed efficiency (fat-corrected milk/dry matter intake) was not affected by treatment (1.69 vs. 1.72 for CON and MC, respectively). Inoculation of corn silage with the homofermentative inoculant increased digestibility of the total mixed ration and increased milk yield by lactating dairy cows.

Con-Current versus Counter-Current Dialysate Flow during CVVHD. A Comparative Study for Creatinine and Urea Removal

Background: Dialysate fluid connection to the membrane in continuous dialysis may affect solute clearance. Although circuit connections are routinely made counter-current to blood flow in intermittent dialysis, no study has assessed the effect of this dialysate fluid flow direction on removal of small solutes creatinine and urea during treatment using continuous veno-venous haemodialysis (CVVHD). Aims: To assess if dialysate flow direction during CVVHD affects small solute removal. Methods: This ethics-approved study recruited a convenience sample of 26 adult ICU patients requiring continuous dialysis to assess urea and creatinine removal for con-current vs. counter-current dialysate flow direction. The circuit was adjusted from continuous veno-venous haemodiafiltration to CVVHD 20 min prior to sampling with no fluid removal. Blood (b) and spent dialysate fluid (f) were taken in both concurrent and counter-current fluid flow at 1 (T1) and 4 (T4) hours with a new treatment. Blood flow was 200 ml/min. Dialysate flow 33 ml/min. Removal of urea and creatinine was expressed as the diafiltrate/plasma concentration ratio: Uf/b and Cf/b respectively. Data lacking normal distribution are presented as median with 25th and 75th interquartile ranges (IQR), otherwise as mean with SD and assessed with the independent t test for paired data. p < 0.5 was considered significant. Results: Fifteen male patients were included with a median (IQR) age of 67 years (52-75), and APACHE ΙΙ score 17 (14-19) with all patients meeting RIFLE criteria ‘F'. At both times, the counter-current dialysate flow was associated with higher mean (SD) diafiltrate/plasma concentration ratios: T1 0.87 (0.16) vs. 0.77 (0.10), p = 0.006; T2 0.96 (0.16) vs. 0.76 (0.09), p < 0.001 for creatinine and T1 0.98 (0.09) vs. 0.81 (0.09), p < 0.001; T2 0.99 (0.07) vs. 0.82 (0.08), p < 0.001 for urea. Conclusion: Counter-current dialysate flow during CVVHD for ICU patients is associated with an approximately 20% increase in removal of small solutes creatinine and urea. Video Journal Club ‘Cappuccino with Claudio Ronco' at http://www.karger.com/?doi=441270.

Comparison of the effects of PRKAR1A and PRKAR2B depletion on signaling pathways, cell growth, and cell cycle control of adrenocortical cells

The cyclic AMP/protein kinase A signaling cascade is one of the main pathways involved in the pathogenesis of adrenocortical tumors. The PKA R1A and R2B proteins are the most abundant regulatory subunits in endocrine tissues. Inactivating mutations of PRKAR1A are associated with Carney complex and a subset of sporadic tumors and the abundance of R2B protein is low in a subset of secreting adrenocortical adenomas. We previously showed that PRKAR1A and PRKAR2B inactivation have anti-apoptotic effects on the adrenocortical carcinoma cell line H295R. The aim of this study was to compare the effects of PRKAR1A and PRKAR2B depletion on cell proliferation, apoptosis, cell signaling pathways, and cell cycle regulation. We found that PRKAR2B depletion is compensated by an upregulation of R1A protein, whereas PRKAR1A depletion has no effect on the production of R2B. The depletion of either PRKAR1A or PRKAR2B promotes the expression of Bcl-xL and resistance to apoptosis; and is associated with a high percentage of cells in S and G2 phase, activates PKA and MEK/ERK pathways, and impairs the expression of IkB leading to activate the NF-κB pathway. However, we observed differences in the regulation of cyclins. The depletion of PRKAR1A leads to the accumulation of cyclin D1 and p27kip, whereas the depletion of PRKAR2B promotes the accumulation of cyclin A, B, cdk1, cdc2, and p21Cip. In conclusion, although the depletion of PRKAR1A and PRKAR2B in adrenocortical cells has similar effects on cell proliferation and apoptosis; loss of these PKA subunits differentially affects cyclin expression.

Comparison and Reproducibility of Techniques for Fluid Status Assessment in Chronic Hemodialysis Patients

BACKGROUND

Several methods have been developed to assess the hydration status in chronic hemodialysis (HD) patients. The aim of this study was to compare body bioimpedance spectroscopy (BIS) with ultrasound (US) lung comet score (ULCs), B-type natriuretic peptide (BNP) and inferior vena cava diameter (IVCD) by US for the estimation of dry weight before and after HD and to analyze all methods in terms of fluid status variations induced by HD. An additional aim of this study was to establish the interoperator reproducibility of these methods.

METHODS

Two nephrologists evaluated BIS, ULCs, IVCD during inspiration (min) and expiration (max), the inferior vena cava collapsibility index (IVCCI) as well as BNP before and after HD in 30 patients. The same operators measured BIS, ULCs and IVCD in 28 HD patients in a blinded fashion.

RESULTS

There was a significant reduction in BIS, ULCs, IVCD and BNP after HD (p < 0.001), but a less significant reduction in IVCCI (p = 0.13). There was a significant correlation between BIS and ULCs, BNP and indexed IVCD (IVCDi)min (p < 0.05) before and after HD, and between BIS and IVCDimax only before HD.

CONCLUSION

All methods were able to describe hyperhydration before and after HD, except for IVCCI after HD. All techniques correlated with BIS before HD. After HD, ULCs correlated better with BIS than IVCD in terms of evaluation of fluid status. It could be expected that the ULCs can give a real-time evaluation of interstitial water. The reproducibility of the measurement of BIS, IVCD and ULCs between the two operators was high.

B-type natriuretic Peptide in the critically ill with acute kidney injury

Introduction. Acute kidney injury (AKI) is common in the intensive care unit (ICU) and associated with poor outcome. Plasma B-type natriuretic peptide (BNP) is a biomarker related to myocardial overload, and is elevated in some ICU patients. There is a high prevalence of both cardiac and renal dysfunction in ICU patients. Aims. To investigate whether plasma BNP levels in the first 48 hours were associated with AKI in ICU patients. Methods. We studied a cohort of 34 consecutive ICU patients. Primary outcome was presence of AKI on presentation, or during ICU stay. Results. For patients with AKI on presentation, BNP was statistically higher at 24 and 48 hours than No-AKI patients (865 versus 148 pg/mL; 1380 versus 131 pg/mL). For patients developing AKI during 48 hours, BNP was statistically higher at 0, 24 and 48 hours than No-AKI patients (510 versus 197 pg/mL; 552 versus 124 pg/mL; 949 versus 104 pg/mL). Conclusion. Critically ill patients with AKI on presentation or during ICU stay have higher levels of the cardiac biomarker BNP relative to No-AKI patients. Elevated levels of plasma BNP may help identify patients with elevated risk of AKI in the ICU setting. The mechanism for this cardiorenal connection requires further investigation.

Body composition and heart rate variability to achieve dry weight and tolerance

Autonomic dysfunction in patients with end- stage renal disease is associated with poor prognosis. Heart rate variability (HRV), determined by the standard deviation of the normal R- R interval, has been reported to be a useful evaluation of cardiac autonomic modulation. The relationship between HRV and hydration status (HS) can be analyzed by whole body bioimpedance spectroscopy. This allows a classification of patients according the combination of HS with predialysis systolic blood pressure. Differences in HRV can be studied in patients with high over hydration, but normal or low blood pressure, with respect to fluid-overloaded/hypertensive patients and normohydrated/normotensive patients. In conclusion, the assessment of the autonomic nervous system response to the hemodialysis treatment in end- stage renal disease patients, classified according to a reliable and quantitative measurement of their fluid overload, could permit better management of both arterial blood pressure and HS.

International survey on the management of acute kidney injury in critically ill patients: year 2007

INTRODUCTION

Several aspects of acute kidney injury (AKI) management, including medical approaches to AKI patients and the optimal form of renal replacement therapy (RRT), remain a matter of debate.

SUBJECTS AND METHODS

The responses of 440 participants to a questionnaire on several points of AKI management, submitted during the 4th International Course on Critical Care Nephrology in June 2007, were analyzed.

RESULTS

The most common answer to the definition of AKI was the use of the RIFLE criteria (55%), followed by the presence of oligoanuria (24%). Responders seemed to preferentially start dialysis within a creatinine range from 2.3-3.4 mg/dl (28%) to 3.4-4.5 mg/dl (26%) and with a urine output level of 150-200 ml/12 h (43%). About 30% of responders showed that they would prescribe dialysis only in case of severe fluid overload (requiring mechanical ventilation and/or causing impaired skin integrity). Continuous RRT is used by most specialists (86%), followed by intermittent hemodialysis (65%), sustained low-efficiency dialysis (28%) and peritoneal dialysis (30%). The preferred RRT dosage was '35 ml/kg/h' (46%) but 37% of responders did not explicitly answer this critical question. Bleeding, hypotension, filter clotting, vascular access and sepsis treatment were the most frequent complications and concerns of RRT.

CONCLUSIONS

New classifications such as the RIFLE criteria did improve the well-known uncertainty about the definition of AKI. Awareness of the prescription and standardization of an adequate treatment dose seemed to have increased in recent years, even if there is still a significant level of uncertainty on this specific issue. Several concerns and RRT complications, such as bleeding and anticoagulation strategies, still need further exploration and development.

Oxidative stress and 'monocyte reprogramming' after kidney transplant: a longitudinal study

Uremia has been implicated in increased oxidative stress (OS) and decreased monocyte HLA-DR expression in chronic kidney disease (CKD) patients. Thus, one would expect normalization of these parameters after successful kidney transplant (KTx). Our aim was to describe patterns of OS and HLA-DR expression after KTx and to explore the effect of renal function and different immunosuppression regimens. 30 KTx patients (20 male; 48 +/- 11 years) were enrolled and compared with 20 healthy controls. We measured advanced oxidation protein products (AOPP) and the percentage of monocytes expressing HLA-DR (%DR+) before (preKTx) and after KTx (on days 2, 30, 90, 180 and after 1 year). Compared to controls, patients had a higher preKTx AOPP (152.6 vs. 69.3 micromol/l; p < 0.001). AOPP decreased at 48 h after KTx, achieving values similar to controls. Thereafter, it increased again and remained significantly higher compared to controls, returning to preKTx levels at 90 days. Prior to KTx there was a trend for lower %DR+ in KTx patients compared to controls (96 vs. 98%; NS). Following KTx, patients had a lower %DR+ in the 1st month; then it gradually returned to preKTx levels during the 1st year; at no time did it reach a value similar to controls. Cyclosporine (CyA)-treated patients had a significantly higher AOPP (161.5 vs. 99.5 micromol/l; p = 0.03) and a lower %DR+ (91.7 vs. 96.4; p < 0.05) at 30 days than patients on tacrolimus (FK). Patients on mycophenolate mofetil (MMF) showed a low AOPP (106.9 vs. 168.1 micromol/l; p = 0.05) and a high %DR+ (96.7 vs. 88.2%; p = 0.001) than those on everolimus. After 3 months, CyA-treated patients had a non-significant increase in AOPP levels, whereas those on FK showed a decrease (p < 0.05) as did those treated with MMF (p < 0.05). Successful KTx reduced but did not normalize AOPP, suggesting ongoing OS, perhaps due to persistent mild renal dysfunction and the effects of immunosuppression. HLA-DR expression remained low after KTx, which may be a possible contributing factor to infectious complications after transplantation. Immunosuppressive agents appear to have diverse effects on OS and HLA-DR expression.

A functional haplotype in the 5' flanking region of the factor VII gene is associated with an increased risk of coronary heart disease

AIMS

The aim of this study was to investigate associations between coronary heart disease risk and polymorphisms in the coagulation factor (F)VII gene in participants of a large prospective study.

METHODS

One thousand nine hundred and fifty-seven men were genotyped for four FVII polymorphisms, -670A-->C, -402G-->A, a 10 base pair insertion at -323 (0 > 10) in the promoter, and R353Q in the structural gene. Associations among genotypes and estimated haplotypes, plasma FVII levels, and coronary heart disease risk were evaluated, and the function of the promoter polymorphisms was assessed in reporter gene assays.

RESULTS

The -670A-->C and -402G-->A polymorphisms were in complete allelic association. The haplotype containing -670C and -402A (frequency =0.23) was associated with significantly increased plasma FVII coagulant activity and increased risk of an initial coronary event, particularly acute myocardial infarction, which remained after correction for conventional risk factors. In contrast, the -323 insertion and Q353 alleles (frequency =0.11 and 0.10, respectively) were associated with decreased plasma FVII levels, but hazard ratios for coronary events in carriers of these alleles were not significantly different from unity. In transiently transfected hepatoma cells, increased basal expression of the reporter gene was directed by a promoter fragment with rare haplotype -670C/-630G/-402A rather than by a promoter fragment with common haplotype -670A/-630A/-402G; -402A was not responsible for this effect.

CONCLUSIONS

The promoter haplotype, -670C/-630G/402A, was associated with significantly increased plasma FVII coagulant activity, risk of an initial coronary event, particularly acute myocardial infarction, and reporter gene expression.

Combined segregation and linkage analysis of fibrinogen variability in Israeli families: evidence for two quantitative-trait loci, one of which is linked to a functional variant (-58G > A) in the promoter of the alpha-fibrinogen gene

The association of alpha- and beta-fibrinogen polymorphisms with plasma fibrinogen levels was examined in a sample of 452 family members from 80 Israeli kindreds. The measured genotype analysis indicated that the beta-fibrinogen -455G > A polymorphism was not associated with fibrinogen levels, while the alpha-fibrinogen -58G > A locus showed a significant association with fibrinogen levels (chi2= 17.7; df = 3; p < 0.001), with the -58A allele being associated with higher levels. Segregation analysis in this sample suggested a recessive quantitative-trait locus (QTL) with a major effect that controlled the sex- and age-adjusted fibrinogen levels. Results from a combined segregation/linkage analysis indicated that a single QTL influencing plasma fibrinogen is in gametic equilibrium with the beta-fibrinogen -455G > A and alpha-fibrinogen -58G > A polymorphisms. An extended analysis with a two-QTL model significantly improved the fit of the model (p < or = 0.001), and gave support for linkage between the fibrinogen QTL and the alpha-fibrinogen polymorphism. In vitro analysis with a DNA fragment containing this variant, linked to a reporter gene, showed 2-fold higher expression of the A allele compared to the G allele in the liver cell line HepG2, both under basal conditions and after stimulation with interleukin 6. These results demonstrate that two QTLs are jointly involved in determining plasma fibrinogen levels in this sample of families, one of which is located close to a functional variant in the alpha-fibrinogen locus.

Oxidized low density lipoprotein suppresses expression of inducible cyclooxygenase in human macrophages

Atherogenesis involves several aspects of chronic inflammation and wound healing. Indeed, the atheroma is considered a special case of tissue response to injury. Injurious stimuli may include lipoproteins trapped within lesions where protein and lipid moieties have undergone chemical modifications. We have studied the effect of oxidized low density lipoproteins (ox-LDL) on inducible cyclooxygenase (Cox-2) in human monocyte-derived macrophages exposed to bacterial lipopolysaccharide (LPS). Levels of both Cox-2 and constitutive cyclooxygenase (Cox-1) were assessed using Western blot analysis. Prior incubation of macrophages with ox-LDL resulted in a strong inhibition of Cox-2 induced by LPS, without effect on Cox-1. The inhibitory effect was dependent on ox-LDL concentration and its onset was early in time (already detectable 1 hour after macrophage exposure to ox-LDL). Native LDL, and other forms of modified LDL, were without effect. The inhibition was dependent on endocytosis of ox-LDL and could be reproduced using the lipid extract from ox-LDL. Lysophosphatidylcholine, 7beta-hydroxycholesterol, and 7-oxocholesterol failed to mimic the inhibition, but oxidized arachidonic acid-containing phospholipids, produced by autoxidation of 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine, markedly inhibited Cox-2. The observation that ox-LDL downregulates Cox-2 in human macrophages may explain the fact that, within atheromata, the transformation of macrophages into foam cells results in attenuation of the inflammatory response, thus contributing to progression of atherogenesis.

Characterization of Bordetella pertussis strains of recent isolation

During the clinical trial conducted in Italy to evaluate the efficacy of new acellular pertussis vaccines, the most favorable conditions for the recovery and characterization of Bordetella pertussis strains, isolated from children with cough, were adopted. The nasopharyngeal aspirates were collected and sent to the laboratory in refrigerated conditions within 24 hours. Charcoal agar selective and non selective plates were used, and most of the isolates were recovered after 3-4 days of incubation. Confirmation of all suspected colonies included the use of biochemical tests and specific agglutination reaction with B. pertussis antiserum. Serotyping of fimbriae, susceptibility to erythromycin and DNA fingerprinting by Pulsed Field Gel Electrophoresis (PFGE), were performed to characterize B. pertussis isolates and to determine relatedness among different strains. Serotype 1,3 was the most represented in the bacterial population examined. A predominant pulsetype (PTA) characterized most of the isolates accounting for 71.4% of the strains examined. Eight subclones (23.5%) and three unrelated pulsetypes were also found. No resistant strains to erythromycin were detected.

Antibody kinetics and long-term sero-prevalence in the Italian clinical trial of acellular pertussis vaccines

In the Italian Pertussis Vaccine Trial, data were collected to evaluate the persistence of anti-pertussis antibodies. A sub-cohort of 1275 children was followed for this purpose until a mean age of 21 months. An additional evaluation included pooled cross-sectional analysis of serum specimens collected for analysis of cough illnesses. Antibodies to PT, FHA and PRN were measured by ELISA using a standardized technique. With both acellular vaccines in the study (the Chiron Biocine three-component and SmithKline Beecham three-component vaccines) there was a fast and steep decrease of mean geometric titres for PT, FHA and PRN in the months immediately following vaccination. Titres were close to the detection limit 15 months after the end of primary immunization. The immunogenicity of the whole-cell study vaccine (produced by Connaught Laboratories, Inc. Swiftwater, USA) was poor as determined one month after the third dose and no antibody was detected in nearly all children 15 months after the end of vaccination.

Comparison of Laparoscopic versus Conventional Treatment of Ovarian Endometrioma

An observational prospective cohort study was conducted with a historical control group and 140 infertile women with the laparoscopic diagnosis of ovarian endometrioma over 1 cm diameter. The groups were comparable regarding age, duration of infertility, and disease severity. All patients had a follow-up of 12 months after treatment, and at least one patent tube. The laparoscopic group (group A) consisted of 46 woman, 35 of whom received suppressive treatment with danazol, Gestinone, or leuprolide acetate for 4 to 6 months. In the control group (group B), 94 women underwent diagnostic laparoscopy plus 6 months of danazol or Gestinone therapy. After 3 months, microsurgery by laparotomy was performed. During the follow-up, period 24 pregnancies were achieved in group A (52%) and 58 in group B (61%, chi2 0.796). Fifteen (48%) of 31 women with cysts 1 to 3 cm in group A conceived, as did 52 (62%) of 81 in group B. Nine (60%) of the 15 with cysts over 3 cm in group A, and 7 (58%) of 12 in group B conceived. No significant difference was found among the suppressive drugs in either group. Only 4 (36%) of the 11 women in group A not receiving suppressive treatment became pregnant. No significant difference (p >0.05) was found when comparing the combined treatment group (57%). According to the revised classification of endometriosis, 18 (51%) of 35 pregnancies were achieved in women with moderate disease in group A and 41 (64%) of 64 in group B. In those with severe disease, 6 (55%) of 11 became pregnant in group A and 17 (57%) of 30 in group B. There was no significant difference between the groups when comparing global results, ovarian endometrioma size, medical treatment, and severity of endometriosis. Given comparable surgical expertise, operative laparoscopy should be the procedure of choice in the treatment of ovarian endometrioma whenever possible, due to its recognized advantages.

Adherence of Borrelia burgdorferi and Borrelia hermsii to mammalian cells in vitro

This study investigated the ability of Borrelia burgdorferi and Borrelia hermsii to attach the surface of several types of in vitro-cultured mammalian cells. Borreliae showed different adhesion efficiencies depending on cell type and temperature. Temperatures both lower and higher than 33 degrees and 37 degrees C respectively, decreased the adhesion of borreliae which preferentially adhere to human fibroblast-like cells. The adhesion process, mediated by structures exposed onto the surface of the microorganisms, also proved to be sensitive to the treatment of mammalian cells with hyaluronidase and sialidase, confirming that carbohydrate receptors are involved in the adhesion of borreliae to eukaryotic cells.

Amitriptyline-related peripheral neuropathy. Case report

Although amitriptyline is not usually regarded as toxic to the peripheral nervous system (PNS) and is even prescribed by some for neuropathic pain, there are sporadic reports of peripheral neuropathy following overdose or prolonged use of the drug. The scarcity of data leads us to report a case we have followed for 3 years clinically and electromyographically. A 54 year old man on oral amitriptyline 150 mg uninterruptedly for 2 years consulted us for lower limb paresthesias and was found on clinical examination to have reduced ankle jerks and mild distal global hypoesthesia. EMG yielded a pattern of sensorimotor neuropathy compatible with axonal disease in all four limbs. The history was unremarkable and the laboratory data were within normal limits. After discontinuation of amitriptyline therapy both the clinical and EMG pattern gradually normalized. We draw attention to the possible risk, infrequent though it is, of PNS neurotoxicity of a widely used drug reputedly harmless from this point of view.