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The geometrically frustrated spin-1 Blume-Capel model on an infinite sawtooth chain is exactly solved by the transfer matrix method. The magnetization, ground-state phase diagram, magnetocaloric properties, and specific heat of the system are investigated. The results indicate that: (i) Magnetization plateaus appear at zero temperature. Their number depends on the sign of the crystal field D. For D≥0 there are two magnetization plateaus; however, for D<0 five plateaus exist. At a finite temperature, thermal excitation will destroy these plateaus completely. (ii) Phase transition between any two long-range-ordered ground states, whose spin configurations are given in phase diagram, is the first-order one. The macroscopic degeneracy of the ground states described by the entropy only exists at phase coexistence points. (iii) As temperature approaches zero, magnetocaloric properties and entropy change sharply near phase coexistence points. (iv) The crossovers of the specific heat from a single-peak structure to double-peak ones can signal the phase coexistence points in ground-state phase diagram.

MicroRNAs are small noncoding RNA molecules that regulate gene expression at the post-transcriptional level. Compelling evidence reveals that there is a causative link between microRNAs deregulation and lung cancer development and metastasis. The aim of present study was to explore the function of miR-140-3p in the development and metastasis of lung cancer cell. Using real-time PCR, we detected the miR-140-3p expression of lung cancer tissues and its pared non-lung cancer tissue. Then, we evaluated the role of miR-140-3p in cell proliferation, invasion and migration using MTT, colony formation assay, Transwell invasion and Transwell migration assay in lung cancer cell lines. As a result, miR-140-3p expression level was lower in lung cancer tissues compared to adjacent normal lung cancer tissue. After miR-140-3p was upregulated in A549 or H1299 cells, cell proliferation, invasion and migration was notably attenuated. Furthermore, we identified ATP6AP2, which is associated with adenosine triphosphatases (ATPases), was a directly target of miR-140-3p in lung cancer cells. In conclusion, our data suggest miR-140-3p/ATP6AP2 axis might act as a potential therapeutic biomarker for lung cancer.

Objective: To assess the effectiveness of mindfulness-based stress reduction (MBSR) for chronic insomnia and combined depressive or anxiety symptoms of older adults aged 75 years and over., Design: A randomized, controlled, single-blind clinical trial., Patients and Methods: Participants included 60 adults aged 75 years and over with chronic insomnia. Participants were randomly assigned to the eight-week MBSR group or the wait-list control group. Assessments using the Pittsburgh Sleep Quality Index (PSQI), Self-rating Anxiety Sale (SAS), and Geriatric Depression Scale (GDS) were taken at baseline and post-treatment. For each outcome measure, a repeated measures analysis of variance was used to detect changes across assessments., Results: There was a significant time × group interaction for the PSQI global score (P = .006); the MBSR group had a decrease in the PSQI global score (Cohen׳s d = 1.12), while the control group did not (Cohen׳s d = -0.06). Among the PSQI components, there was a significant time × group interaction for daytime dysfunction (P = .048); Cohen׳s d of the MBSR group was 0.76, while Cohen׳s d of control group was -0.04. There was no significant time × group interaction for the SAS score (P = .116), while for the GDS there was a significant time × group interaction (P = .039); the Cohen׳s d value for the MBSR group was 1.20, and it was 0.12 for the control group., Conclusion: This study demonstrated that the MBSR program could be a beneficial treatment for chronic insomnia in adults aged 75 years and older., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Autophagy favors cell survival under hypoxia, and increasing evidence revealed that microRNAs regulate autophagy. We report here hypoxia increased the expression of miR-96 in prostate cancer cells, and miR-96 stimulated autophagy by suppressing MTOR. We found that inhibition of miR-96 abolished hypoxia-induced autophagy. Paradoxically, ectopic over-expression of miR-96 to a certain threshold, also abolished the hypoxia-induced autophagy. Further studies have shown that high levels of miR-96 inhibited autophagy through suppressing ATG7, a key autophagy-associated gene. Importantly, the miR-96 expression level threshold was determined, and the effects of miR-96 on autophagy on either side of the threshold were opposite. These data demonstrate hypoxia-induced autophagy is at least partially regulated by miR-96; miR-96 can promote or inhibit autophagy by principally inhibiting MTOR or ATG7 depending on the expression levels of miR-96. Our observation might reveal a novel regulatory mode of autophagy by microRNAs under hypoxia.

Objective: To investigate whether understanding of glaucoma is associated with psychological disturbance and vision-related quality of life (QoL) in patients with glaucoma., Design: A prospective, hospital-based, cross-sectional study., Setting: Shanghai, China., Participants: Five hundred patients with glaucoma were included in the study. Participants were asked to complete the glaucoma comprehension questionnaire, the Hospital Anxiety and Depression Scale (HADS) questionnaire, and the 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25)., Outcome Measures: Sociodemographic data and clinical data were collected. Multivariate adjusted linear regression analyses were performed to examine factors related to psychological disorder and QoL. The relationship between understanding of glaucoma and psychological status or QoL was analysed., Results: The mean age of patients was 56.5±17.2 years, and the mean duration of glaucoma was 4.6±6.3 years. About half (54.2%) of the patients had primary open angle glaucoma, 37.2% had primary angle closure glaucoma, and 8.6% had secondary glaucoma. The total score and the subscores of knowledge of glaucoma, compliance and habits were all negatively correlated with the HADS-Depression and HADS scores. For NEI VFQ-25, the total comprehension score was positively related to general vision, near activity, distance activity, social function, colour vision and the composite score. Habits had a significant influence on both HADS-Depression and the composite score of NEI VFQ-25., Conclusions: The level of understanding about glaucoma is an independent factor negatively associated with psychological disturbance and positively associated with QoL in patients with glaucoma. However, it is a subjective factor which can be regulated, so imparting knowledge about glaucoma and establishing appropriate habits might help patients alleviate psychological disturbance and enhance their QoL., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Patients with colorectal cancer (CRC) often develop liver metastases, in which case surgery is considered the only potentially curative treatment option. However, liver surgery is associated with a risk of ischemia-reperfusion (IR) injury, which is thought to promote the growth of colorectal liver metastases. The influence of IR-induced tumor necrosis factor alpha (TNF-α) elevation in the process still is unknown. To investigate the role of TNF-α in the growth of pre-existing micrometastases in the liver following IR, we used a mouse model of colorectal liver metastases. In this model, mice received IR treatment seven days after intrasplenic injections of colorectal CT26 cells. Prior to IR treatment, either TNF-α blocker Enbrel or low-dose TNF-α, which could inhibit IR-induced TNF-α elevation, was administered by intraperitoneal injection., Results: Hepatic IR treatment significantly promoted CT26 tumor growth in the liver, but either Enbrel or low-dose TNF-α pretreatment reversed this trend. Further studies showed that the CT26 + IR group prominently increased the levels of ALT and AST, liver necrosis, inflammatory infiltration and the expressions of hepatic IL-6, MMP9 and E-selectin compared to those of CT26 group. Inhibition of TNF-α elevation remarkably attenuated the increases of these liver inflammatory damage indicators and tumor-promoting factors., Conclusion: These findings suggested that inhibition of TNF-α elevation delayed the IR-enhanced outgrowth of colorectal liver metastases by reducing IR-induced inflammatory damage and the formation of tumor-promoting microenvironments. Both Enbrel and low-dose TNF-α represented the potential therapeutic approaches for the protection of colorectal liver metastatic patients against IR injury-induced growth of liver micrometastases foci.

Our previous studies have suggested that Staphylococcus aureus L-forms are able to pass through the placental barrier of mice from the maternal side to the fetal body and affect fetal growth and development, but little is known about the direct influence of S. aureus L-forms on embryos during the critical period of organogenesis. Mouse embryos at gestational day 8.5 were cultured in vitro for 48 h with 0, 50, 100, 200 or 400 c.f.u. S. aureus L-forms ml(-1). At the end of the culture period, the mouse embryos were assessed morphologically for viability, growth and development. Bacteriological and immunohistochemical staining were used to determine the existence of S. aureus L-forms in embryonic tissues. We found that both crown-rump length and head length of mouse embryos exposed to S. aureus L-forms at a concentration of 50 c.f.u. ml(-1) were reduced. When the mouse embryos were exposed to 100, 200 or 400 c.f.u. S. aureus L-forms ml(-1), the total morphological score, number of somites, dry embryo weight, yolk sac diameter, crown-rump length and head length were significantly lower than those of the control group. With the increased concentration of S. aureus L-forms in the culture medium, there were fewer normally developed embryos and more embryos with abnormalities or retardation in growth. S. aureus L-forms detected by Gram-staining and immunohistochemical detection of antigen were found in the tissues of embryos infected by S. aureus L-forms. These data suggest that S. aureus L-forms exert a direct teratogenic effect on cultured mouse embryos in vitro.

Background: This study aimed to explore potential associations between single nucleotide polymorphisms (SNPs) of the x-ray repair cross-complementing group 1 (XRCC1) and cleft lip and palate transmembrane protein 1-like (CLPTM1L) and non-small cell lung cancer (NSCLC) susceptibility in non-smoker Chinese patients., Methods: A total of 200 NSCLC patients and 200 healthy controls with matched age and gender were recruited for genotyping of XRCC1 SNPs (rs2256507 and rs1001581) and CLPTM1L SNPs (rs401681 and rs4975616). Association of these SNPs with NSCLC risk was evaluated by computing the odds ratio (OR) and 95% confidence interval (CI) from multivariate unconditional logistic regression analyses with adjustment for gender and age., Results: The frequencies of genotype and allele in these four loci (rs2256507, rs1001581, rs401681, and rs4975616) were not significantly different between the cases and controls, or between either of the histological subgroups (adenocarcinoma and squamous cell carcinoma) and controls., Conclusions: Although these SNPs are associated with NSCLC risk in patients with a tobacco-smoking habit, this study demonstrated that XRCC1 and CLPTM1L gene SPNs are not linked with NSCLC risk in non-smoking patients, indicating that molecular mechanisms of NSCLC betwee tobacco smokers and non-smokers may be different. Future studies are needed to uncover the underlying molecular mechanisms for NSCLC in non-smokers.

Objective: To investigate the respiratory function and pulmonary hemodynamics in patients with portal hypertension (PHT)., Methods: A total of 148 patients with PHT were divided into three groups according to Child-Pugh classification. Results of blood biochemistry test, lung function test, arterial blood gas analysis, free portal pressure (FPP) and pulmonary hemodynamics measurements of the three Child-Pugh grade groups were compared with those of the control group., Results: The overall incidence of arterial hypoxemia was 27.0% in PHT patients. Arterial oxygen tension (PaO(2) ) had a significant negative correlation with FPP (r=-0.76, P<0.01) and Child-Pugh grade (r=-0.42, P<0.01), as well as a positive correlation with systemic vascular resistance (SVR, r=0.24, P=0.01). Alveolar-arterial oxygen difference (A-aDO(2) ) increased in Child-Pugh grade C group when compared with Child-Pugh grade A and B groups (P<0.05). Restrictive impairment of lung function was seen in Child-Pugh grade C group. Direct measurement of the hemodynamics in PHT patients revealed a hyperdynamic disturbance in both systemic and portal venous systems, and was illustrated in pulmonary circulation as an increase of mean pulmonary arterial pressure (MPAP) and pulmonary arterial wedged pressure (PAWP) as well as a decrease of pulmonary vascular resistance (PVR)., Conclusions:   High output and low resistance are the key characteristics of pulmonary circulation in PHT patients and the decrease of PVR can be detected even when liver function is still compensated., (© 2012 The Authors. Journal of Digestive Diseases © 2012 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Blackwell Publishing Asia Pty Ltd.)

Background: The development of abnormal involuntary movements or dyskinesia is a serious complication of L-3,4-dihydroxyphenylalanine (L-DOPA) therapy for Parkinson's disease (PD)., Objective: To evaluate the correlation between dopamine transporter (DAT) regulated by L-DOPA and the pathogenesis of dyskinesia in PD rats., Methods: Thirty rats were used to establish the PD model by injecting 6-hydroxydopamine into the right medial forebrain bundle. The sham surgery rats (n = 4) received 4 μl of physiological saline. Then, 19 rats in which PD has been successfully induced were randomly assigned to the L-DOPA (20 mg/kg/day; n = 15) or model (saline; n = 4) group. After 4 weeks of treatment, (131)I-N-(3-fluoropropyl)-2β-carbomethoxy-3 β-(4-iodophenyl)nortropane was injected into the rats, and images of DAT in the brain were acquired using a storage phosphor plate. The levels of DAT-specific radioactivity uptake in the bilateral corpora striata (left/right) were compared., Results: There was no difference in DAT-specific radioactivity uptake between the bilateral corpora striata in the sham surgery rats. The images were clear and symmetrically distributed in the corpora striata. In PD model rats, the DAT-specific radioactivity uptake decreased on the lesioned side and the ratios of uptake between the corpora striata were increased. Accumulation of the radioligand on the lesioned side was sparse. In the L-DOPA group, the average ratio values were significantly increased in dyskinetic rats and reduced in nondyskinetic rats. In addition, the differences between the bilateral corpora striata were reduced in nondyskinetic rats., Conclusion: L-DOPA was shown to downregulate DAT in some PD model rats. That process may be involved in the pathogenesis of dyskinesia., (Copyright © 2011 S. Karger AG, Basel.)

In order to overcome the low conversion and complex post-treatment, four different polymerization procedures were adopted to prepare the magnetic polymer latexes. The results clearly show that the strategy using magnetic emulsion template-dosage is the most effective and feasible. Based on the optimized procedure, various factors including the type of initiators such as oil soluble initiator, water soluble initiator, redox initiator system, crosslinking agent, functional monomers etc. were systematically studied. Magnetic polymer latex with high monomer conversion of 83% and high magnet content of 31.8% was successfully obtained. Besides, core-shell structured magnetic polymer latex with good film forming property was also prepared, which is promising for potential applications such as magnetic coatings and modification of cementitious materials with controlled polymer location., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Studies have shown that immune cells play a key role in lung cancer development. Five SNPs (rs1494555, rs7737000, rs20541, rs1057972 and rs2857261) are associated with lung cancer risk among Caucasians and/or African-Americans, but the polymorphisms may be implicated in different susceptibilities for lung cancer across different populations because of underlying genetic heterogeneity. We therefore conducted a study to examine this relationship in non-smoking Chinese. As a result , no significant associations were observed between SNPs and NSCLCs, whetehr of squamous cell or adenocarcinoma type. Results indicated polymorphisms of IL-7R, IL-13 and IL-15 are not major contributors to NSCLC susceptibility, although we can not rule out synergistic effects with cigarette smoke in NSCLC development in smoking Chinese.

Aim: To examine the contribution of vascular membrane-associated prostaglandin E2 synthase-1 (mPGES-1) to acute blood pressure homeostasis., Methods: Angiotensin II (AngII, 75 pmol·kg⁻¹·min⁻¹) was continuously infused via the jugular vein into wild-type and mPGES-1(-/-) mice for 30 min, and blood pressure was measured by carotid arterial catheterization. RT-PCR and immunohistochemistry were performed to detect the expression and localization of mPGES-1 in the mouse arterial vessels. Mesenteric arteries were dissected from mice of both genotypes to study vessel tension and measure vascular PGE2 levels., Results: Wild-type and mPGES-1(-/-) mice showed similar blood pressure levels at baseline, and the acute intravenous infusion of AngII caused a greater increase in mean arterial pressure in the mPGES-1(-/-) group, with a similar diuretic and natriuretic response in both groups. mPGES-1 was constitutively expressed in the aortic and mesenteric arteries and vascular smooth muscle cells of wild-type mice. Strong staining was detected in the smooth muscle layer of arterial vessels. Ex vivo treatment of mesenteric arteries with AngII produced more vasodilatory PGE2 in wild-type than in mPGES-1(-/-) mice. In vitro tension assays further revealed that the mesenteric arteries of mPGES-1(-/-) mice exhibited a greater vasopressor response to AngII than those arteries of wild-type mice., Conclusion: Vascular mPGES-1 acts as an important tonic vasodilator, contributing to acute blood pressure regulation.

Objective: To explore the anti-angiogenesis and tumor cell growth suppressive effects resulted from gene silencing by RNAi in BxPC-3 human pancreatic cancer cells., Methods: The designation and transfection of vascular endothelial growth factor (VEGF)-siRNA lentivirus was carried out in vitro. Real-time PCR and western blot were conducted to measure the expression levels of VEGF mRNA and protein. Flow cytometry was employed to evaluate cell apoptosis and cell death. A lactate dehydrogenase (LDH) assay was used to assess the cytotoxicity of VEGF-siRNA. A 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was used to picture the cellular growth. For the in vivo study, BxPC-3 cells were injected subcutaneously into nude mice to form xenografts. The mice were divided into three groups according to the intervention used. The control group, the negative control group and the knockdown group of mice were injected with saline, an empty lentivirus vehicle and lentivirus carrying VEGF-siRNA, respectively. None of the mice died during the study. When these mice were killed, the xenografts were collected and the tumor sizes of the different groups were compared. Finally, immunohistochemistry was used to assess the VEGF expression level and microvascular density., Results: After the transfection of VEGF-siRNA lentivirus, the cellular expression of VEGF mRNA decreased to 50% of the control and the VEGF protein in the BxPC-3 cells decreased to 30% of the control. Apoptosis and cell death increased after transfection of the VEGF-siRNA lentivirus. The LDH assay showed high cytotoxicity induced by VEGF-siRNA lentivirus transfection. The MTT assay showed slower cellular growth in the knockdown cells. Tumor growth suppression was observed in nude mice that had received the VEGF-siRNA lentivirus transfection, and the tumor sizes of the xenografts in this group were clearly smaller than those in other two groups. VEGF expression and microvascular density were significantly decreased., Conclusion: Vascular endothelial growth factor gene silencing via VEGF-siRNA can effectively inhibit the production of VEGF and exert an anti-angiogenesis and tumor cell growth suppressive effect both in vitro and in vivo.

Objective: To investigate the changes in retinal vessels, especially macular capillaries, under high IOP using the Rhesus monkey high IOP model., Methods: The trabecular meshwork of the adult Rhesus monkey was cauterized by laser to induce increased IOPs with different degrees of damage. The eyeballs were enucleated, and the optic nerves were stained with toluidine blue in semithick slices. Part of the retina was observed under electron microscope, and the rest was stained by the ADPase method. The damage levels of the optic nerve were evaluated by axon count, and the pathological appearance of the macular capillaries were observed., Results: Five mildly damaged eyes, three moderately damaged eyes and three severely damaged eyes were evaluated. Dense and intact perifoveal vascular rings were observed in all the eyes. The vessels' area percentages, as well as area, perimeter and diameter of the foveal avascular zones, were measured, and no statistically differences were found among different groups (P-values were 0.269, 0.500, 0.951, and 0.555 separately). The ultra structures of the normal capillaries showed regular tubes and intact basement membranes, while lipoid substances in capillary tubes, swollen mitochondria in endothelial cell bodies, and uneven basement membranes were found in the high IOP-damaged eyes., Conclusions: Compared with normal eyes, no obvious differences were found in macular microvessels and foveal avascular zones in the Rhesus monkey model of high IOP. However, presence of swollen mitochondria in endothelial cells and lipoid substances in capillary tubes might suggest that high IOP could damage the capillary endothelial cells.

The crystalline behaviors of PCL(poly(epsilon-caprolactone) )thin film on Si and KBr substrates have been studied in-situ using FTIR with a heat stage. In the crystalline process, due to the decrease in free volume and the increase in interaction among different molecules, the peak of C=O shifted to lower wave number and the crystalline peak of C-O-C and C-H appeared. The degree of crystallinity has been calculated through the comparison between the peaks of crystal and amorphous parts. FTIR study on the films cast from solution with different concentrations showed that the thicker the film is, the higher crystallinity it has. This may be due to the substrate effect or geometric confinement. It was also shown that under the same preparation condition, the film on KBr wafer had higher degree of crystallinity than that of film on Si wafer.

The critical dynamics of the kinetic Glauber-Ising model is studied on a family of the diamond-type hierarchical lattices with various branches. By carrying out the time-dependent real-space renormalization-group transformation to the master equation of the systems considered, the dynamic exponent is calculated. We find that the dynamic exponent depends on fractal dimension d(f) or the branch number m in a generator, and that it increases with the increase of d(f) or m. We notice that for the case of m=1 (one-dimensional spin chain, d(f)=1) our result z=2 is the same as the exact result obtained by Glauber, and for the case of m=2 (the simplest one in the diamond-type hierarchical lattices, d(f)=2) the exponent z=2.626 is higher than those of the two-dimensional regular lattice and the triangular lattice.

In this paper, we present a multispin transition mechanism, which is an extension of the Glauber one, to investigate critical dynamics. By exactly solving the master equation, the influence of the multispin transition mechanism on the dynamic critical behavior is studied for the Gaussian model with nearest-neighbor interactions on d-dimensional lattices (d=1, 2, and 3). The time evolution of magnetization is exactly calculated, and the exact results of relaxation time and dynamic critical exponent are obtained. Our models are divided into two kinds: one is the spin-cluster transition and the other is the arbitrary multispin transition. It is found that there are different relaxation times, but the same dynamical critical exponent for different kinds of multispin transitions. The results show that the dynamical critical exponents are independent of spatial dimensions and configurations of transitional spins, and that the dynamical critical exponent is the same as that of the Glauber dynamics, and thus give a strong support to the simple single-spin-transition dynamics. Finally, we give a brief discussion on the results.

The coarsening process of the droplets in a two-phase polymer blend (PP/EVAc) was studied under two-dimensional and three-dimensional conditions using a phase contrast microscope and computer image analyzer. The results showed that under three-dimensional conditions the growth of the droplet's radius with time follows r(3) approximately t(1.01), corresponding to the evaporation-condensation theory of Lifshitz-Slyozov, r(3) approximately t, while under two-dimensional conditions the growth law is r(3) approximately t(1.31). The growth rate of the droplets under two-dimensional conditions is faster than that under three-dimensional conditions. This difference is caused by an interfacial interaction (wetting effects) between the substrates and polymer blend. The existence of the interface promoted the coarsening process of the polymer blend under two-dimensional conditions. Copyright 2001 Academic Press.

Recent studies have indicated that the relaxation rate of the (1)H-(13)C multiple-quantum coherence is much slower than that of the (1)H-(13)C single-quantum coherence for non-aromatic methine sites in (13) C labeled proteins and in nucleic acids at the slow tumbling limit. Several heteronuclear experiments have been designed to use a multiple-quantum coherence transfer scheme instead of the single-quantum transfer method, thereby increasing the sensitivity and resolution of the spectra. Here, we report a constant time, gradient and sensitivity enhanced HMQC experiment (CT-g/s-HMQC) and demonstrate that it has a significant sensitivity enhancement over constant time HMQC and constant time gradient and sensitivity enhanced HSQC experiments (CT-g/s-HSQC) when applied to a (13)C and (15) N labeled calmodulin sample in D(2)O. We also apply this approach to 3D NOESY-HMQC and doubly sensitivity enhanced TOCSY-HMQC experiments, and demonstrate that they are more sensitive than their HSQC counterparts.

Previously we demonstrated a sensitivity enhancement of the original TROSY experiment by a factor of [Formula: see text] by the use of the sensitivity enhanced TROSY (en-TROSY) scheme. Here, we develop a gradient and sensitivity enhanced TROSY experiment (gs-TROSY), which is designed to select magnetization transfer pathways that suppress spectral artifacts and reduce the number of required phase cycles while having minimal loss of sensitivity. Both of these experimental methods (en-TROSY and gs- TROSY) have been combined with a water flip-back scheme which provides a further increase in sensitivity for labile NH groups by avoiding water saturation. We also apply these TROSY schemes to 3D NOESY-TROSY and 3D TOCSY-TROSY experiments.

Necrotic enteritis was reproduced in broiler chickens by mixing cultures of Clostridium perfringens in the feed. Mortality due to necrotic enteritis was higher among chickens fed rations based on wheat, rye, barley, and oat groats than among chickens fed corn-based rations. Addition of pentosanase to a wheat-based diet did not affect the level of mortality due to necrotic enteritis. Addition of pectin and guar gum to different rations severely reduced growth rate and eliminated necrotic enteritis from test birds. Addition of glucose to a corn-based diet caused a small increase in mortality due to necrotic enteritis.