The effects of air stress during storage and low packing density on the fermentation and aerobic stability of corn silage inoculated with Lactobacillus buchneri 40788.

We determined if a microbial inoculant could improve the fermentation and aerobic stability of corn silage subjected to various challenges during storage that included an air stress challenge and low packing density. In Experiment 1, whole-plant corn was untreated (CTR) or treated (INO, Lactobacillus buchneri 40788 and Pediococcus pentosaceus 12455. Five individually replicated 7.5-L silos, at a density of 240 kg of dry matter (DM)/m3, for each treatment were kept sealed (NAS) for 19 wk, air stressed early (ES, 3 h/wk for wk 1-9), or air stressed late during storage (LS, 3 h/wk for wk 10-19). Inoculation increased the number of agar-culturable lactic acid bacteria regardless of air stress status, but it did not affect the relative abundance of Lactobacillus. Early, but not late air stress, resulted in silages with a higher relative abundance of Acetobacter when compared with NAS. Silages treated with INO had greater concentrations of acetic acid than CTR. Numbers of yeasts were lowest for INO regardless of air stress and CTR-LS had the most yeasts among all treatments. Silages that were not air stressed had a higher relative abundance of Candida tropicalis than air stressed silages. Monascus purpureus was detected in ES and LS but not in NAS, and its relative abundance was numerically higher in CTR-ES than in INO-ES and statistically higher in CTR-LS compared with INO-LS. Early air stress numerically reduced aerobic stability compared with NAS, and there was a statistical tendency for lower stability in LS compared with NAS. Inoculation improved aerobic stability regardless of when the air stress occurred. In Experiment 2, corn silage was prepared with the same primary treatments of CTR and INO but was packed at a low (LD; 180 kg of DM/m3) or a normal (ND; 240 kg of DM/m3) density and sealed (NAS) or air stressed (AS; 24 h on d 28, 42, and 89) for 92 d of storage. The concentration of acetic acid was greater in INO compared with CTR and in AS compared with NAS. Numbers of yeasts were lower in NAS compared with AS regardless of inoculation and they were lower in INO-AS compared with CTR-AS. Treatment with INO improved aerobic stability but the improvement was better in NAS versus AS and better in ND versus LD. Overall, our experiments corroborate past findings showing that INO markedly improves the aerobic stability of corn silage but they are the first to show that improvement can be sustained even when the silage was exposed to regular air stresses and when packed at a low density.

Effects of Lactobacillus hilgardii 4785 and Lactobacillus buchneri 40788 on the bacterial community, fermentation and aerobic stability of high-moisture corn silage.

AIMS: To evaluate the capacity of Lactobacillus hilgardii and Lactobacillus buchneri on modifying the bacterial community and improving fermentation and aerobic stability of high-moisture corn (HMC). METHODS AND RESULTS: High-moisture corn was untreated (CTR), treated with L. hilgardii (LH) or L. buchneri (LB) at 600 000 CFU per gram fresh weight, or with L. hilgardii and L. buchneri at 300 000 CFU per gram fresh weight each (LHLB), and stored for 10, 30 or 92 days. Compared to CTR, inoculated silages had higher Lactobacillaceae relative abundance, lower yeasts numbers and higher aerobic stability. Treatment with LHLB resulted in a higher acetic acid concentration than LH and higher 1,2 propanediol concentration than LB, such differences were numerically greater at 10 and 30 days but statistically greater at 92 days. At 10 days, all inoculated silages were more stable than CTR, but LHLB was even more stable than LB or LH. CONCLUSIONS: The combination of L. hilgardii and L. buchneri had a synergistic effect on yeast inhibition, leading to greater improvements in aerobic stability as early as 10 days after ensiling. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus hilgardii, especially in combination with L. buchneri, can improve the aerobic stability of HMC after a very short period of ensiling.

Persistent infection with neurotropic herpes viruses and cognitive impairment.

BACKGROUND: Herpes virus infections can cause cognitive impairment during and after acute encephalitis. Although chronic, latent/persistent infection is considered to be relatively benign, some studies have documented cognitive impairment in exposed persons that is untraceable to encephalitis. These studies were conducted among schizophrenia (SZ) patients or older community dwellers, among whom it is difficult to control for the effects of co-morbid illness and medications. To determine whether the associations can be generalized to other groups, we examined a large sample of younger control individuals, SZ patients and their non-psychotic relatives (n=1852). Method Using multivariate models, cognitive performance was evaluated in relation to exposures to herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2) and cytomegalovirus (CMV), controlling for familial and diagnostic status and sociodemographic variables, including occupation and educational status. Composite cognitive measures were derived from nine cognitive domains using principal components of heritability (PCH). Exposure was indexed by antibodies to viral antigens. RESULTS: PCH1, the most heritable component of cognitive performance, declines with exposure to CMV or HSV-1 regardless of case/relative/control group status (p = 1.09 × 10-5 and 0.01 respectively), with stronger association with exposure to multiple herpes viruses (ß = -0.25, p = 7.28 × 10-10). There were no significant interactions between exposure and group status. CONCLUSIONS: Latent/persistent herpes virus infections can be associated with cognitive impairments regardless of other health status.

Heritability of functioning in families with schizophrenia in relation to neurocognition.

UNLABELLED: The role of daily functioning is an integral part of the schizophrenia (SZ) phenotype and deficits in this trait appear to be present in both affected persons and some unaffected relatives; hence we have examined its heritability in our cohort of African American schizophrenia families. There is now ample evidence that deficits in cognitive function can impact family members who are not themselves diagnosed with SZ; there is some, but less evidence that role function behaves likewise. We evaluate whether role function tends to "run in families" who were ascertained because they contain an African American proband diagnosed with SZ. METHODS: We analyzed heritability for selected traits related to daily function, employment, living situation, marital status, and Global Assessment Scale (GAS) score; modeling age, gender, along with neurocognition and diagnosis as covariates in a family based African-American sample (N=2488 individuals including 979 probands). RESULTS: Measures of role function were heritable in models including neurocognitive domains and factor analytically derived neurocognitive summary scores and demographics as covariates; the most heritable estimate was obtained from the current GAS scores (h2=0.72). Neurocognition was not a significant contributor to heritability of role function. CONCLUSIONS: Commonly assessed demographic and clinical indicators of functioning are heritable with a global rating of functioning being the most heritable. Measures of neurocognition had little impact on heritability of functioning overall. The family covariance for functioning, reflected in its heritability, supports the concept that interventions at the family level, such as evidenced-based family psychoeducation may be beneficial in schizophrenia.

Genetic risk factors for type 2 diabetes with pharmacologic intervention in African-American patients with schizophrenia or schizoaffective disorder.

An increased prevalence of type 2 diabetes (T2D) in schizophrenia (SCZ) patients has been observed. Exposure to antipsychotics (APs) has been shown to induce metabolic dysregulation in some patients but not all treated patients. We hypothesized that important candidate genes for T2D may increase risk for T2D in African-American patients with SCZ or schizoaffective disorder. The PAARTNERS study comprises African-American families with at least one proband with SCZ or schizoaffective disorder. The current study of PAARTNERS SCZ and schizoaffective disorder cases (N=820) examined single nucleotide polymorphisms (SNPs) within select T2D candidate genes including transcription factor 7-like 2 (TCF7L2), calpain 10 (CAPN10), and ectoenzyme nucleotide pyrophosphatase phosphodiesterase 1 (ENNP1) for association with prevalent T2D. We report the association of TCF7L2 (rs7903146) with T2D under both additive and recessive models for the risk allele T. Specifically, the odds ratio (OR) for having T2D was 1.4 (p=0.03) under an additive model and 2.4 (p=0.004) under a recessive model. We also report a marginally significant TCF7L2 by AP treatment interaction that should be investigated in future studies. CAPN10 (rs3792267) was marginally associated with T2D with OR=1.5 (p=0.08) when considering the model GG vs. AG/AA with risk allele G. ENPP1 (rs1044498) was not associated with T2D. We conclude TCF7L2, a risk factor for T2D in the general population, is also a risk factor for T2D in African-American patients with SCZ or schizoaffective disorder. Research is needed to determine if T2D associated polymorphisms are of interest in the pharmacogenetics and future treatment choices of antipsychotics in African-American patients.

Linkage analysis of schizophrenia in African-American families.

While many studies have sought a window into the genetics of schizophrenia, few have focused on African-American families. An exception is the Project among African-Americans to Explore Risks for Schizophrenia (PAARTNERS), which seeks to identify novel and known risk variation for schizophrenia by genetic analyses of African-American families. We report a linkage study of diagnostic status in 217 African-American families using the Illumina Linkage Panel. Due to assumed incomplete and time-dependent penetrance, we performed linkage analysis using two different treatments of diagnosis: (1) treating both affected and unaffected individuals as informative for linkage (using the program SIBPAL) and (2) treating only affected individuals as informative (using the program MERLIN). We also explore three definitions of affected status: narrowly defined schizophrenia; one broadened to include schizoaffective disorder; and another including all diagnoses indicating psychosis. Several regions show a decrease in the evidence for linkage as the definition broadens 8q22.1 (rs911, 99.26 cM; SIBPAL p-value [p] goes from 0.006 to 0.02), 16q24.3 (rs1006547, 130.48 cM; p from 0.00095 to 0.0085), and 20q13.2 (rs1022689, 81.73 cM; p from 0.00015 to 0.032). One region shows a substantial increase in evidence for linkage, 11p15.2 (rs722317, 24.27 cM; p from 0.0022 to 0.0000003); MERLIN results support the significance of the SIBPAL results (p=0.00001). Our linkage results overlap two broad, previously-reported linkage regions: 8p23.3-p12 found in studies sampling largely families of European ancestry; and 11p11.2-q22.3 reported by a study of African-American families. These results should prove quite useful for uncovering loci affecting risk for schizophrenia.

A polychaete hunchback ortholog.

We report the first characterization of a segmentation gene homologue in the basal polychaete Capitella capitata using a pan-annelid cross-species antibody to the hunchback-like gene product. In flies, the gap segmentation gene hunchback (hb) encodes a C(2)H(2) zinc-finger transcription factor that plays a pivotal role in patterning the anterior region of the fly body plan. The hb orthologue in Capitella (Cc-hb) is expressed maternally and in all micromere and macromere cells throughout cleavage. At gastrulation, nuclear Cc-hb protein is expressed in the micromere-derived surface epithelium that undergoes epiboly and in the large vegetal blastomeres that gradually become internalized. During organogenesis, Cc-hb is expressed in the developing gut epithelium, the prostomial and pygidial epithelium, and in a subset of differentiated neurons in the adult central nervous system. Cc-hb is not expressed in the segmental precursor cells in the trunk. The Cc-hb expression domains in Capitella are similar to those reported for the leech hb orthologue (LZF2), and many of the observed differences between the annelid classes correlate with changes in life history. The lack of detectable annelid hb protein in the trunk at the time of AP pattern formation in leech and in polychaete suggests that the anterior organizing function of hb in flies originated in the arthropod or insect lineage.

Clinical utility of echocardiography in the management of implantable ventricular assist devices.

BACKGROUND: The high mortality rate of congestive cardiac failure, the cost and complications of cardiac transplantation, and the waiting list mortality rate resulting from donor organ scarcity have encouraged the development of surgical techniques as bridges to transplantation or as long-term palliative therapy. Implantable left ventricular assist devices are now routinely used as such a bridge, and within the REMATCH Trial, as permanent palliative devices in nontransplant candidates. These are mechanical managements with myriad mechanical complications and pitfalls. Echocardiography has been extensively used in our institution to detect and diagnose previously documented and hitherto unencountered complications of these procedures. METHODS AND RESULTS: The role of echocardiography in these procedures, including preoperative patient selection, intraoperative transesophageal echocardiography, and postoperative troubleshooting and late follow-up, is discussed. We describe our clinical echocardiographic approach, which has developed over 91 assist-device procedures. The relative frequency and clinical impact of specific anatomic, physiologic, hemodynamic, and mechanical features are described. New techniques such as the Doppler quantification of assist device inflow obstruction are illustrated, as are the device cannula position, the detection of device valve failure, and the parameters related to the remodeling procedure. CONCLUSIONS: Echocardiography in heart failure surgery has proved to be an invaluable tool in the diagnosis and management of mechanical complications. The experience gained in our institution may serve as an aid to new surgical programs treating these critically ill patients.

Management strategies for high-risk cardiac surgery: improving outcomes in patients with heart failure.

BACKGROUND: Surgical heart failure management is the fastest growing aspect of cardio-vascular surgery. Advances in cardiac surgical techniques have changed the number and types of operations permitted physicians and thus broadened the complexity of patients recommended for operation. METHODS: Surgeons, anesthesiologists and cardiologists face hemodynamic and patho-physiological challenges that can be optimally overcome only by modifying treatment strategies. Because many treatment standards are still evolving in this rapidly advancing field, a team of cardiovascular surgeons and anesthesiologists convened to share clinical experience and impressions and discuss practical issues related to high-risk patients undergoing heart surgery. RESULTS: Heart failure pathophysiology, surgical heart failure management, including mitral reconstruction and left ventricular remodeling, cardiopulmonary bypass weaning, inotropic support, transesophageal echocardiography and acute cardiovascular collapse after cardiac surgery are discussed. CONCLUSION: This article is intended to guide clinicians to improve patient care and outcomes in this special population by providing specific guidance on the appropriate use of inotropic and mechanical support in patients undergoing high-risk procedures using innovative techniques.

The leech hunchback protein is expressed in the epithelium and CNS but not in the segmental precursor lineages.

We are interested in identifying the regulatory genes involved in segmental pattern formation in annelids. The Drosophila segmentation gene hunchback (hb) is critical for the proper anteroposterior development of the fly embryo, but its function outside the diptera is currently unknown. Here, the protein expression pattern of Leech Zinc Finger II (LZF2), a leech orthologue of hb is characterized. In early embryogenesis, LZF2 protein is expressed in a subset of micromeres and is later expressed in the micromere-derived epithelium of the provisional epithelium and prostomium. LZF2 protein is detected in the ventral nerve cord during organogenesis, first in interganglionic muscle cells and later in subsets of neurons in each neuromere of the CNS. The location of immunoreactive cells during development and the similarity of the expression pattern of LZF2 to the expression of the Caenhorhabditis elegans hb homologue hbl-1 suggests that LZF2 plays a role in the morphogenetic movements of leech gastrulation and later in CNS specification but not in anteroposterior pattern formation.

MR imaging of human brain at 3.0 T: preliminary report on transverse relaxation rates and relation to estimated iron content.

PURPOSE: To determine the transverse relaxation rates R2 and R2' from several gray matter regions and from frontal cortical white matter in healthy human brains in vivo and to determine the relationship between relaxation rates and iron concentration [Fe]. MATERIALS AND METHODS: Six healthy adults aged 19-42 years underwent thin-section gradient-echo sampling of free induction decay and echo magnetic resonance (MR) imaging at 3.0 T. Imaging covered the mesencephalon and basal ganglia. RESULTS: Relaxation rates (mean +/- SD) were highest in globus pallidus (R2 = 25.8 seconds-1 +/- 1.1, R2' = 12.0 seconds-1 +/- 2.1) and lowest in prefrontal cortex (R2 = 14.4 seconds-1 +/- 1.8, R2' = 3.4 seconds-1 +/- 1.1). Frontal white matter measurements were as follows: R2 = 18.0 seconds-1 +/- 1.2 and R2' = 3.9 seconds-1 +/- 1.2. For gray matter, both R2 and R2' showed a strong correlation (r = 0.92, P < .001 and r = 0.90, P < .001, respectively) with [Fe]. Although the slopes of the regression lines for R2' versus [Fe] and for R2 versus [Fe] were similar, the iron-independent component of R2' (2.2 seconds-1 +/- 0.6), the value when [Fe] = 0, was much less than that of R2 (12.7 seconds-1 +/- 0.7). CONCLUSION: The small iron-independent component R2', as compared with that of R2, is consistent with the hypothesis that R2' has higher iron-related specificity.

Left ventricular diastolic filling with an implantable ventricular assist device: beat to beat variability with overall improvement.

OBJECTIVES: We studied the effects of left ventricular (LV) unloading by an implantable ventricular assist device on LV diastolic filling. BACKGROUND: Although many investigators have reported reliable systemic and peripheral circulatory support with implantable LV assist devices, little is known about their effect on cardiac performance. METHODS: Peak velocities of early diastolic filling, late diastolic filling, late to early filling ratio, deceleration time of early filling, diastolic filling period and atrial filling fraction were measured by intraoperative transesophageal Doppler echocardiography before and after insertion of an LV assist device in eight patients. A numerical model was developed to simulate this situation. RESULTS: Before device insertion, all patients showed either a restrictive or a monophasic transmitral flow pattern. After device insertion, transmitral flow showed rapid beat to beat variation in each patient, from abnormal relaxation to restrictive patterns. However, when the average values obtained from 10 consecutive beats were considered, overall filling was significantly normalized from baseline, with early filling velocity falling from 87 +/- 31 to 64 +/- 26 cm/s (p < 0.01) and late filling velocity rising from 8 +/- 11 to 32 +/- 23 cm/s (p < 0.05), resulting in an increase in the late to early filling ratio from 0.13 +/- 0.18 to 0.59 +/- 0.38 (p < 0.01) and a rise in the atrial filling fraction from 8 +/- 10% to 26 +/- 17% (p < 0.01). The deceleration time (from 112 +/- 40 to 160 +/- 44 ms, p < 0.05) and the filling period corrected by the RR interval (from 39 +/- 8% to 54 +/- 10%, p < 0.005) were also significantly prolonged. In the computer model, asynchronous LV assistance produced significant beat to beat variation in filling indexes, but overall a normalization of deceleration time as well as other variables. CONCLUSIONS: With LV assistance, transmitral flow showed rapidly varying patterns beat by beat in each patient, but overall diastolic filling tended to normalize with an increase of atrial contribution to the filling. Because of the variable nature of the transmitral flow pattern with the assist device, the timing of the device cycle must be considered when inferring diastolic function from transmitral flow pattern.

Intraoperative echocardiography is indicated in high-risk coronary artery bypass grafting.

BACKGROUND: Intraoperative echocardiography is a valuable monitoring and diagnostic technology used in cardiac surgery. This reports our clinical study of the usefulness of intraoperative echocardiography to both surgeons and anesthesiologists for high-risk coronary artery bypass grafting. METHODS: From March to November 1995, 82 consecutive high-risk patients undergoing coronary artery bypass grafting were studied in a four-stage protocol to determine the efficacy of intraoperative echocardiography in management planning. Alterations in surgical and anesthetic/hemodynamic management initiated by intraoperative echocardiography findings were documented in addition to perioperative morbidity and mortality. RESULTS: Intraoperative echocardiography initiated at least one major surgical management alteration in 27 patients (33%) and at least one major anesthetic/hemodynamic change in 42 (51%). Mortality and the rate of myocardial infarction in this consecutive high-risk study population using intraoperative echocardiography and in a similar group of patients without the use of intraoperative echocardiography was 1.2% versus 3.8% (not significant) and 1.2% versus 3.5% (not significant), respectively. CONCLUSIONS: We conclude that when all of the isolated diagnostic and monitoring applications of perioperative echocardiography are routinely and systematically performed together, it is a safe and viable tool that significantly affects the decision-making process in the intraoperative care of high-risk patients undergoing primary isolated coronary artery bypass grafting and may contribute to the optimal care of these patients.

Experimental and numerically modeled effects of altered loading conditions on pulmonary venous flow and left atrial pressure in patients with mitral regurgitation.

Pulmonary venous flow measured by pulsed-wave Doppler transesophageal echocardiography reflects the effects of mitral regurgitation on left atrial pressure contour. To assess the relationship between pulmonary venous flow and left atrial pressure in patients with mitral regurgitation under altered loading conditions, we studied 25 patients with 3+ or 4+ mitral regurgitation and a control group by measuring pulmonary venous flow with transesophageal echocardiography and left atrial pressures after administering saline solution (n = 6), nitroglycerin (n = 6), phenylephrine (n = 6), or nitroprusside (n = 7). After administration, the left atrial pressure v wave increased in the group given phenylephrine, concomitant with an increased diastolic flow. In contrast, the left atrial pressure v wave decreased in the group given nitroglycerin, concomitant with a decreased diastolic flow. Changes in diastolic flow were closely related to changes in the left atrial pressure v wave under all loading conditions (r = 0.91; p < 0.0001). Numeric modeling of left atrial pressure and pulmonary venous diastolic flow corroborated the experimental findings. We conclude that changes in pulmonary venous diastolic flow are closely related to changes in the left atrial pressure v wave in mitral regurgitation, under altered loading conditions.

Prediction of right ventricular dysfunction after left ventricular assist device implantation.

BACKGROUND: Right ventricular dysfunction (RVD) significantly affects mortality and morbidity after left ventricular assist device (LVAD) implantation, and its occurrence often is unpredictable. The aim of the present study was to identify predictors of RVD after LVAD implantation. METHODS AND RESULTS: We studied right ventricular (RV) hemodynamics in 28 patients before and after LVAD implantation with a rapid-response thermistor pulmonary artery catheter. Measurements included mean right atrial pressure (RAP), mean pulmonary arterial pressure (PAP), cardiac index, transpulmonary gradient (TPG), pulmonary vascular resistance (PVR), RV end-diastolic and end-systolic volume indexes (EDVI and ESVI, respectively), and RV ejection fraction (RVEF). We regarded patients who had RAP > or = 15 mm Hg at LVAD explantation (n = 8) or who required an RV assist device (n = 3) as the RVD group (n = 11). The other patients were categorized as the RV nondysfunctional group (RVN, n = 17). Before LVAD implantation, the RVD group had larger RV volumes (200 +/- 107 versus 125 +/- 46 mL/m2 for EDVI; 177 +/- 109 versus 104 +/- 48 mL/m2 for ESVI) and higher preload (23 +/- 6 versus 17 +/- 6 mm Hg for RAP) and afterload (20 +/- 9 versus 13 +/- 6 mm Hg for TPG; 5.9 +/- 3.0 versus 3.8 +/- 2.0 Wood units for PVR) than the RVN group (P < .05 for all). RVEF and PAP did not differ significantly. LVAD implantation remarkably improved RV hemodynamics in both groups, decreasing RV volumes, preload, and afterload and increasing RVEF in all patients, but post-LVAD PAP tended to be higher in the RVD group. Multivariate logistic regression analysis revealed that RAP and TPG before LVAD implantation and an acute decrease (delta) in PAP by LVAD were significant predictors of RVD (P < .05). The sensitivity for predicting RVD by a combination of at least two of these three predictors (RAP > or = 20 mm Hg, TPG > or = 16 mm Hg, and delta PAP < or = 10 mm Hg) was 82%, and the specificity was 88%. CONCLUSIONS: Dilated right ventricle with increased RV preload and afterload predisposes to RVD after LVAD implantation. Not only baseline parameters but also the immediate hemodynamic response to the LVAD are predictive, and a combination of these parameters may be useful in predictions of the occurrence of RVD after LVAD implantation.