Altered cognitive control network mediates the association between long-term pain and anxiety symptoms in primary dysmenorrhea

Neuroimaging studies have demonstrated the association of the cognitive control network (CCN) with the maintenance of chronic pain. However, whether and how dorsolateral prefrontal cortex (DLPFC), a key region within the CCN, is altered in menstrual pain is unclear. In this study, we aimed to investigate alterations in the DLPFC functional connectivity network in patients with primary dysmenorrhea (PDM). The study comprised 41 PDM patients and 39 matched healthy controls (HCs), all of whom underwent a resting-state functional MRI scan during the menstrual stage. All participants were instructed to complete the clinical assessment before the MRI scan. We used the DLPFC as the seed in resting-state functional connectivity (rsFC) analysis to investigate the difference between PDM patients and HCs. Compared to HCs, PDM patients showed increased right DLPFC rsFC at the bilateral lingual gyrus, dorsal anterior cingulate cortex (dACC), and middle cingulate cortex, and decreased left DLPFC rsFC at the right orbital frontal cortex. In addition, increased right DLPFC-bilateral dACC connectivity mediated the association between disease duration and the self-rating anxiety scale (SAS) scores in PDM patients. We confirmed that the DLPFC-dACC rsFC was associated with higher SAS scores, which could mediate the association between disease duration and anxiety symptoms in patients with PDM. Our findings provide central pathological evidence for an abnormal rsFC of the CCN in PDM patients, which may contribute to a better understanding of the neuropathophysiological mechanisms underlying PDM.

Research Status and Prospects of Acupuncture in Perioperative Medicine Over the Past Decade: A Bibliometric Analysis

Background

Over the past decade, acupuncture in the perioperative period has attracted great interest, and a growing number of related literature has been published.

Purpose

To analyze the general information and identify the research hotspots and trends of acupuncture in perioperative medicine in the last 10 years by bibliometric analysis.

Methods

We searched the Web of Science Core Collection for publications on acupuncture in perioperative medicine from 2013 to 2023. The articles and reviews were collected with no language restriction. CiteSpace and VOSviewer software were used for bibliometric and visual analysis of relevant literature.

Results

A total of 814 bibliographic records were retrieved. Overall, the annual number of publications showed an increasing trend. China and its institutions were in a leading position regarding the publication number. With comparatively more scientific collaboration with China, the USA ranked second. Shanghai University of Traditional Chinese Medicine was the most prolific institution. Ha, In-Hyuk had the most publications, and Han JS and Lee A were the most cited authors. Medicine was the most popular journal and Journal of Clinical Oncology had the highest impact factor. "Acupuncture", "electroacupuncture" and "postoperative pain" were the top three keywords. The most popular topics were postoperative pain, postoperative ileus, and postoperative nausea and vomiting according to the keywords and references. And the clusters of postoperative cognitive dysfunction, anxiety, and breast cancer attracted relatively more attention recently.

Conclusion

This study summarized the research status, hotspots, and trends of acupuncture in perioperative medicine in the past decade, which may aid researchers in better understanding this field. The research hotspots primarily focused on postoperative pain management and postoperative gastrointestinal function. The research of acupuncture for postoperative cognitive dysfunction, cancer-related surgery, and psychological states were the main frontiers topics and may be the focus in the future.

[Imaging findings of supratentorial embryonal tumor with multilayered rosettes in children]

We analyzed and summarized the imaging characteristics and clinical data of seven pediatric supratentorial embryonal tumors with multilayered rosettes (ETMR). There were four boys and three girls aged from two to six years old. Pediatric supratentorial ETMR often presented large cystic and solid mass, calcification, significant mass effect and mild peritumoral edema. The solid part often showed heterogeneous mild enhancement. In combination with the location of tumor and age of onset, the typical imaging manifestations of supratentorial ETMR in children are valuable for accurate diagnosis.

[Application of apparent diffusion coefficient histogram in moderate to severe neonatal hypoxic-ischemic encephalopathy]

Objective: To investigate the diagnostic value of apparent diffusion coefficient (ADC) histogram in quantifying moderate to severe neonatal hypoxic-ischemic encephalopathy (HIE). Methods: A total of 49 children with moderate to severe HIE admitted to the Children's Hospital Affiliated to Nanjing Medical University from July 2015 to September 2018 were retrospectively analyzed. Cranial magnetic resonance imaging (MRI) data of 31 full-term neonates without neurological symptoms and signs who visited the hospital during the same period were recruited as the control group. ImgJ software was used to delineate the whole brain area at the thalamus/basal ganglia level as the area of interest, and MRIcron software was used to obtain ADC histogram parameters. The differences of ADC histogram parameters between HIE group and control group were compared. The correlation between ADC histogram parameters and neonatal neurobehavioral neurological assessment (NBNA) in HIE group was analyzed. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficiency of each parameter. Results: The mean value, minimum value, maximum value, mode-value, variance, heterogeneity and 10%-90% ADC values of HIE group were all greater than those of the control group(634±65,310±36,1 683±18,711±87,66 928±921,5 907±204,477±50,513±53,542±56,568±59,591±61,625±92,661±97,709±105,811±119),the differences were statistically significant(all P<0.05), while mode-count of HIE group was smaller than that of the control group(272±22 to 395±83), and the difference was statistically significant (t=2.996,P<0.05). All the above parameters with statistical differences were correlated with NBNA score, among which mode-count was negatively correlated with NBNA score(r=-0.369,P<0.05), and the rest were positively correlated(all P<0.05). The area under the ROC curve (AUC) of variance had the highest diagnostic efficiency (0.881), followed by 90% ADC value and ADC maximum value. Conclusion: ADC histogram is helpful for the diagnosis of HIE, objectively and quantitatively reflecting the diffusion information of brain, and assessing the severity of HIE.

Wagyu-Angus cross improves meat tenderness compared to Angus cattle but unaffected by mild protein restriction during late gestation

For the spring-calving beef herds, late gestation coincides with winter and early spring, when cows are dependent on feed supplements with low quality hay, which is hard to meet their nutrient requirements. However, the effects of deficiencies of metabolizable protein intake during late gestation on offspring beef quality are unclear. Wagyu cattle have excellent marbling, and insemination with Wagyu vs Angus semen is a practical option for beef producers to improve beef quality. To test, Angus cows (621 ± 73 kg) were selected and randomly separated into two groups. Each group was inseminated with either Angus or Wagyu semen. During the last 90 days of gestation, cows in each group were further separated and received either a low protein diet (85% of the NRC metabolizable protein requirement), which was a low quality hay-based diet common in northwestern region of the U.S., or an adequate protein diet (108% NRC requirement). All progeny was managed together and harvested at a final BW of 576.5 ± 16.6 kg. Wagyu-sired offspring had higher marbling scores and quality grades than Angus (P < 0.01). Protein supplementation did not affect Slice Shear Force (SSF) in either breeds (P = 0.60). However, Wagyu-sired cattle had lower SSF than Angus-sired (P < 0.01). In addition, Wagyu-sired cattle had higher intramuscular fat (P < 0.05) and total collagen content (P < 0.05), but Angus-sired had greater mature collagen cross-links, as shown by higher contents of Pyridinoline (P < 0.01) and Ehrlich Chromogen (P < 0.01). Consistently, the mRNA expression of enzymes catalyzing collagen cross-linking was higher in Angus-sired offspring, including Plod 1 (P < 0.05), Plod 2 (P = 0.08), and P4Hα 2 (P < 0.01). In conclusion, Wagyu-sired cattle had greater tenderness and marbling score compared to Angus-sired, which was associated with lower collagen cross-links. Feeding mature grass hay-based diet with relatively low protein content during late gestation had no major effect on beef quality of subsequent cattle.

[Classification of the types of pediatric posterior fossa brain tumors based on routine MRI using wavelet transformation analysis of whole tumor]

Objective: To evaluate the classification of the types of pediatric posterior fossa brain tumors based on routine MRI (T(1)WI, T(2)WI and ADC) using wavelet transformation analysis of whole tumor. Methods: MRI images of medulloblastoma (n=59), ependymoma (n=13) and pilocytic astrocytoma (n=27) confirmed by pathology before treatments in Children's Hospital of Nanjing Medical University from January 2014 to February 2019 were enrolled in this retrospective study as well as the clinical data of age, gender and symptoms. Registration was performed among the three sequences and wavelet features of ROI were acquired. Afterwards, the top ten features were ranked and trained among groups by using random forest classifier. Finally, the results were compared and analyzed according to the classification. Results: The top ten contribution three sequences and wavelet features of ROI were acquired from the ADC sequence. The random forest classifier achieved 100% accuracy on training data and was validated best accuracy (86.8%) when combined of first and third wavelet features. The sensitivity was 100%, 94.8%, 76.9%, and the specificity was 97.6%, 88.0%, 98.8% respectively. Conclusions: Features based on wavelet transformation of ADC sequence of entire tumor can provide more quantitative information, which could provide help in the differential diagnosis of pediatric posterior fossa brain tumors. The optimum combination to distinguish three pediatric posterior fossa brain tumors is sixth and twelfth wavelet features of ADC sequence.

[Brain alteration in neonates with congenital heart disease using apparent diffusion coefficient histograms]

Objective: To evaluate the value of apparent diffusion coefficient (ADC) histogram in neonatal brain alteration with congenital heart disease (CHD). Methods: MRIs of 60 neonates with CHD confirmed by echocardiography were retrospectively analyzed in Children's Hospital of Nanjing Medical University from January 2012 to December 2016.Twenty-two MRIs of neonates with mild pneumonia or scalp hematoma who were suspicious of brain disease but normal MRI findings were enrolled as normal control.MRIcron and ImgJ softwares were used to acquire ADC histogram.The correlation between the gestational age and ADC histogram values were calculated respectively.Then t-test was used to analyze the differences of the histogram values and the diagnostic efficacy of different parameters was analyzed using the receiver operating characteristic curve. Results: The ADC values were significantly correlated with the gestational age (P<0.05). The 70th-90th ADC, skewness, kurtosis and variance were statistically significant (P<0.05). The area under the curve of the 90th ADC value was the largest at 0.698. Conclusions: The ADC histogram can quantify and objectively provide more diffusion information of brain tissue. It is a rapid and feasible quantitative method to identify brain changes in neonates with CHD.

Three-dimensional spheroid culture of adipose stromal vascular cells for studying adipogenesis in beef cattle

Protocols designed for the adipogenic differentiation of human and mouse cells are commonly used for inducing the adipogenesis of bovine stromal vascular cells. However, likely due to metabolic differences between ruminant and non-ruminant animals, these methods result in only few cells undergoing complete adipogenesis with minimal lipid droplet accumulation. Here, we discuss the development of an adipogenic differentiation protocol for bovine primary cells through a three-dimensional spheroid culture. Stromal vascular cells derived from bovine intramuscular fat were isolated and stored in liquid nitrogen before culturing. Cells were cultured in hanging drops for 3 days to allow for the formation of spherical structures. The spheroids were then transferred to cell culture plates with endothelial basal medium-2 for 3 days and in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with a standard adipogenic cocktail for 3 additional days, which were then allowed to fully differentiate for 3 days in DMEM supplemented with insulin. Compared with conventional two-dimensional culture, cells in a three-dimensional spheroid culture system had higher adipogenic gene expression and consequently contained more adipocytes with larger lipid droplets. In addition, endothelial induction of spheroids prior to adipogenic differentiation is essential for efficient induction of adipogenesis of bovine stromal vascular cells, mimicking in vivo adipose development. In summary, the newly developed three-dimensional spheroid culture method is an efficient way to induce adipogenic differentiation and study adipose development of cells derived from ruminant animals, which also can be used for studying the role of angiogenesis in adipose development.

Genomewide association studies for hematological traits and T lymphocyte subpopulations in a Duroc × Erhualian F resource population

It has been shown that hematological traits can act as important indicators of immune function in both humans and livestock. T lymphocytes are key components of the adaptive immune system, playing a critical role in immune response. To identify genomic regions affecting hematological traits and T lymphocyte subpopulations, we performed both a SNP-based genomewide association study (GWAS) and a haplotype analysis for 20 hematological traits and 8 T cell subpopulations at 3 different time points (d 20, 33, and 35) in a Duroc × Erhualian F intercross population. Bonferroni correction was used to calculate the threshold -values for suggestive and 5% genomewide significance levels. In total, for SNP-based GWAS, we detected 96 significant SNP, including 15 genomewide-significant SNP, associated with 23 hematological traits and 234 significant SNP, including 27 genomewide-significant SNP, associated with 8 T cell subpopulations. Meanwhile, we identified 563 significant SNP, including 7 genomewide-significant SNP, associated with 5 hematological traits and 2,407 significant SNP, including 1,261 genomewide-significant SNP, associated with 8 T cell subpopulations by haplotype analysis. Among the significant regions detected, we propose both the () gene and the () gene on SSC3 as plausible candidate genes associated with CD/CD T lymphocytes at d 20. The findings provide insights into the basis of molecular mechanisms that are involved with immune response in the domestic pig and would aid further identification of causative mutations.

Phonon-Assisted Resonant Tunneling of Electrons in Graphene-Boron Nitride Transistors

We observe a series of sharp resonant features in the differential conductance of graphene-hexagonal boron nitride-graphene tunnel transistors over a wide range of bias voltages between 10 and 200 mV. We attribute them to electron tunneling assisted by the emission of phonons of well-defined energy. The bias voltages at which they occur are insensitive to the applied gate voltage and hence independent of the carrier densities in the graphene electrodes, so plasmonic effects can be ruled out. The phonon energies corresponding to the resonances are compared with the lattice dispersion curves of graphene-boron nitride heterostructures and are close to peaks in the single phonon density of states.

Enhanced mitogenesis in stromal vascular cells derived from subcutaneous adipose tissue of Wagyu compared with those of Angus cattle

Japanese Wagyu cattle are well known for their extremely high marbling and lower subcutaneous adipose tissue compared with Angus cattle. However, mechanisms for differences in adipose deposition are unknown. The objective of this paper was to evaluate breed differences in the structure of subcutaneous adipose tissue, adipogenesis, and mitogenesis of stromal vascular (SV) cells between Wagyu and Angus cattle. Subcutaneous biopsy samples were obtained from 5 Wagyu (BW = 302 ± 9 kg) and 5 Angus (BW = 398 ± 12 kg) heifers at 12 mo of age, and samples were divided into 3 pieces for histological examination, biochemical analysis, and harvest of SV cells. Adipogenesis of SV cells was assessed by the expression of adipogenic markers and Oil Red-O staining, while mitogenesis was evaluated by an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium dromide) test, phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (PKB; AKT). Based on histological analysis, Wagyu had larger adipocytes compared with Angus. At the tissue level, protein expression of peroxisome proliferator-activated receptor γ (PPARG) in Wagyu was much lower compared with that of Angus. Similarly, a lower mRNA expression of PPARG was found in Wagyu SV cells. No significant difference was observed for the zinc finger protein 423 (ZNF423) expression between Wagyu and Angus. As assessed by Oil Red-O staining, Wagyu SV cells possessed a notable trend of lower adipogenic capability. Interestingly, higher mitogenic ability was discovered in Wagyu SV cells, which was associated with an elevated phosphorylation of ERK1/2. There was no difference in AKT phosphorylation of SV cells between Wagyu and Angus. Moreover, exogenous fibroblast growth factor 2 (FGF2) enhanced mitogenesis and ERK1/2 phosphorylation of SV cells to a greater degree in Angus compared with that in Wagyu. Expression of transforming growth factor β 3 (TGFB3) and bone morphogenetic protein 2 (BMP2) in Wagyu SV cells was lower than that of Angus, providing potential clues for breed differences on proliferation of SV cells in these two cattle breeds. The results of this study suggest that subcutaneous adipose-derived SV cells of Wagyu possess a lower trend of adipogenesis but higher mitogenesis compared with those of Angus.

Twist-controlled resonant tunnelling in graphene/boron nitride/graphene heterostructures

Recent developments in the technology of van der Waals heterostructures made from two-dimensional atomic crystals have already led to the observation of new physical phenomena, such as the metal-insulator transition and Coulomb drag, and to the realization of functional devices, such as tunnel diodes, tunnel transistors and photovoltaic sensors. An unprecedented degree of control of the electronic properties is available not only by means of the selection of materials in the stack, but also through the additional fine-tuning achievable by adjusting the built-in strain and relative orientation of the component layers. Here we demonstrate how careful alignment of the crystallographic orientation of two graphene electrodes separated by a layer of hexagonal boron nitride in a transistor device can achieve resonant tunnelling with conservation of electron energy, momentum and, potentially, chirality. We show how the resonance peak and negative differential conductance in the device characteristics induce a tunable radiofrequency oscillatory current that has potential for future high-frequency technology.

CELL BIOLOGY SYMPOSIUM: Impacts of maternal obesity on placental and gut inflammation and health

Obesity in pregnant women is a growing public health concern that negatively affects fetal development and has long-term impacts on offspring health. The placenta plays an essential role in nutrient transport to the fetus and supports fetal growth and development. Maternal obesity (MO) induces an exacerbated proinflammatory milieu in the placenta providing an inflammatory environment for fetuses. The gut is one of the largest immune organs and mainly develops during the fetal stage. Maternal obesity and the corresponding inflammatory uteroplacental environment affect gut development, incurring inflammatory responses in the fetal intestine that further prime or program the offspring gut to enhance inflammation and impair intestinal barrier integrity. This review summarizes the impact of MO on inflammatory responses in placenta and fetal intestine and the long-term effects on offspring intestinal health. Because "leaky gut" is one of the main etiological factors for a number of common diseases, including inflammatory bowel diseases, type I diabetes, and related autoimmune diseases, the adverse effect of MO on the overall health of progeny is further discussed.

Maternal obesity upregulates fatty acid and glucose transporters and increases expression of enzymes mediating fatty acid biosynthesis in fetal adipose tissue depots

Maternal nutrient restriction leads to alteration in fetal adipose tissue, and offspring from obese mothers have an increased risk of developing obesity. We hypothesized that maternal obesity increases fetal adipogenesis. Multiparous ewes (Columbia/Rambouillet cross 3 to 5 yr of age) carrying twins were assigned to a diet of 100% (Control; CON; n = 4) or 150% (Obese; OB, n = 7) of NRC maintenance requirements from 60 d before conception until necropsy on d 135 of gestation. Maternal and fetal plasma were collected and stored at -80°C for glucose and hormone analyses. Fetal measurements were made at necropsy, and perirenal, pericardial, and subcutaneous adipose tissues were collected from 7 male twin fetuses per group and snap frozen at -80°C. Protein and mRNA expression of fatty acid translocase [cluster of differentiation (CD) 36], fatty acid transport proteins (FATP) 1 and 4, insulin-sensitive glucose transporter (GLUT-4), fatty acid synthase (FASN), and acetyl-coA carboxylase (ACC) was evaluated. Fetal weight was similar, but fetal carcass weight (FCW) was reduced (P < 0.05) in OB versus CON fetuses. Pericardial and perirenal adipose tissue weights were increased (P < 0.05) as a percentage of FCW in OB versus CON fetuses, as was subcutaneous fat thickness (P < 0.001). Average adipocyte diameter was greater (P < 0.01) in the perirenal fat and the pericardial fat (P = 0.06) in OB fetuses compared with CON fetuses. Maternal plasma showed no difference (P > 0.05) in glucose or other hormones, fetal plasma glucose was similar (P = 0.42), and cortisol, IGF-1, and thyroxine were reduced (P ≤ 0.05) in OB fetuses compared with CON fetuses. Protein and mRNA expression of CD 36, FATP 1 and 4, and GLUT-4 were increased (P ≤ 0.05) in all fetal adipose depots in OB versus CON fetuses. The mRNA expression of FASN and ACC was increased (P < 0.05) in OB vs. CON fetuses in all 3 fetal adipose tissue depots. Fatty acid concentrations were increased (P = 0.01) in the perirenal depot of OB versus CON fetuses, and specific fatty acid concentrations were altered (P < 0.05) in subcutaneous and pericardial adipose tissue because of maternal obesity. In conclusion, maternal obesity was associated with increased fetal adiposity, increased fatty acid and glucose transporters, and increased expression of enzymes mediating fatty acid biosynthesis in adipose depots. These alterations, if maintained into the postnatal period, could predispose the offspring to later obesity and metabolic disease.

Application of standard addition for the determination of carboxypeptidase activity in Actinomucor elegans bran koji

Leucine carboxypeptidase (EC 3.4.16) activity in Actinomucor elegans bran koji was investigated via absorbance at 507 nm after stained by Cd-nihydrin solution, with calibration curve A, which was made by a set of known concentration standard leucine, calibration B, which was made by three sets of known concentration standard leucine solutions with the addition of three concentrations inactive crude enzyme extract, and calibration C, which was made by three sets of known concentration standard leucine solutions with the addition of three concentrations crude enzyme extract. The results indicated that application of pure amino acid standard curve was not a suitable way to determine carboxypeptidase in complicate mixture, and it probably led to overestimated carboxypeptidase activity. It was found that addition of crude exact into pure amino acid standard curve had a significant difference from pure amino acid standard curve method (p < 0.05). There was no significant enzyme activity difference (p > 0.05) between addition of active crude exact and addition of inactive crude kind, when the proper dilute multiple was used. It was concluded that the addition of crude enzyme extract to the calibration was needed to eliminate the interference of free amino acids and related compounds presented in crude enzyme extract.

Metformin mitigates the impaired development of skeletal muscle in the offspring of obese mice

Background: Maternal obesity is linked with offspring obesity and type 2 diabetes. Skeletal muscle (SM) insulin resistance is central to the development of diabetes. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is inhibited in SM of fetuses born to obese mothers.

Objective: The aim of this study was to evaluate the effect of maternal metformin administration on AMPK activity and reversion of adverse changes in offspring SM of obese mice.

Design: Female weanling C57BL/6J mice received either control diet (CON, 6 mice) or high-fat diet (HFD; OB, 12 mice) for 8 weeks before mating. After mating, mice continued receiving their respective CON or OB diets. In addition, 6 of those 12 mice fed with fat diet also received metformin administration (2 mg per ml in drinking water) throughout gestation and lactation (MET). After weaning at postnatal 21 days, offspring were fed a HFD to mimic a postnatal obesogenic environment until necropsy.

Results: Mothers receiving the fat diet developed obesity. OB offspring showed higher adiposity than CON and MET offspring. AMPK phosphorylation was lower in SM of OB offspring. β-Catenin and myogenic regulatory factors, MyoD and myogenin, were downregulated in OB muscle, whereas the adipogenic marker, peroxisome proliferator-activated receptor-γ, was upregulated compared with CON muscle. Metformin administration prevented these changes in OB offspring SM. OB but not MET offspring demonstrated glucose intolerance. Mitochondrial content decreased, and activities of citrate synthase and β-hydroxyacyl-CoA dehydrogenase also decreased in OB offspring SM, whereas they were recovered in MET offspring SM.

Conclusion: Maternal metformin administration improves SM development in OB offspring.

Upregulation of growth signaling and nutrient transporters in cotyledons of early to mid-gestational nutrient restricted ewes

Multiparous ewes received 100% (control, C, n = 13) or 50% (nutrient restricted, NR, n = 14) of NRC dietary requirements from d28-d78 of gestation. On d78, 5 C and 6 NR ewes were necropsied. The remaining 8 C and 8 NR ewes were fed to 100% of NRC from d78-d135 and necropsied. Maternal blood was collected at both necropsies and at weekly intervals for assay of glucose, insulin and leptin. Fetal blood was collected at d78 and d135 necropsies for assay of glucose and lipids. Cotyledonary (COT) tissue was evaluated for protein and mRNA expression [fatty acid transporter (FATP)1, FATP4, CD36, glucose transporter (GLUT)1 and GLUT3], mRNA expression only [placenta fatty acid binding protein (FABPpm) and lipoprotein lipase (LPL)], or expression of phosphorylated and total protein forms [AMP kinase (AMPK)α, acetyl-CoA carboxylase (ACC), extracellular signal-regulated kinase (Erk)1/2, mammalian target of rapamycin (mTOR) and protein kinase B (Akt)]. On d78, but not d135, placental and fetal weights were reduced (P < 0.05) in NR vs. C ewes. Maternal circulating glucose, insulin and leptin levels were decreased in NR vs. C ewes on d78 (P < 0.05) but similar at d135. Fetal blood glucose and triglyceride levels were lower in NR vs. C ewes (P < 0.05) on d78, but similar on d135. On d78, GLUT1, FATP4, CD36 mRNA and protein expression levels, FABPpm mRNA level, and leptin protein level were all increased (P < 0.05) in COT of NR vs. C ewes. AMPK, ACC, and Erk1/2 activities were also increased (P < 0.05) in NR vs. C COT on d78. In contrast, only FATP4 was increased (P < 0.05) at both the mRNA and protein levels in COT of NR realimented vs. C ewes on d135. These data demonstrate placental adaptation to maternal NR through increasing nutrient transporter production and growth signaling activity.

Fetal muscle development, mesenchymal multipotent cell differentiation, and associated signaling pathways

Enhancing muscle growth while reducing fat accumulation improves the efficiency of animal production. The fetal stage is crucial for skeletal muscle development. Fetal muscle development involves myogenesis, adipogenesis, and fibrogenesis from mesenchymal multipotent cells (MC), which are negatively affected by maternal nutrient deficiencies. Enhancing myogenesis increases the lean-to-fat ratio of animals, enhancing intramuscular adipogenesis increases intramuscular fat that is indispensible for the superior eating properties of meat because fat is the major contributor to meat flavor. The promotion of fibrogenesis leads to the accumulation of connective tissue, which contributes to the background toughness of meat and is undesirable. Thus, it is essential to regulate MC differentiation to enhance lean growth and improve meat quality. To date, our understanding of mechanisms regulating the lineage commitment of MC is limited. In this review, we first discuss the impact of maternal nutrient deficiency on fetal development, offspring body composition, and meat quality. Because maternal nutrition affects fetal muscle through altering MC differentiation, we then review several important extracellular morphogens regulating MC differentiation, including hedgehog, Wingless and Int (Wnt), and bone morphogenic proteins. Possible involvement of epigenetic modifications associated with histone deacetylases class IIa and histone acetyltransferase, p300, in MC differentiation is also discussed.

Increased tau phosphorylation and beta amyloid in the hipocampus of mouse pups by early life lead exposure

The aim of this study was to investigate the effects of maternal lead exposure on the learning and memory ability and expression of tau protein phosphorylation (P-tau) and beta amyloid protein (Abeta) in hippocampus of mice offspring. Pb exposure initiated from beginning of gestation to weaning. Pb acetate administered in drinking solutions was dissolved in distilled deionized water at the concentrations of 0.1%, 0.5% and 1% groups. On the 21 th of postnatal day, the learning and memory ability of the mouse pups was tested by Water Maze test and the Pb levels in blood and hippocampus of the offspring were also determined. The expression of P-tau and Abeta in hippocampus was measured by immunohistochemistry and Western blotting. The Pb levels in blood and hippocampus of all exposure groups were significantly higher than that of the control group ( P < 0.05). In Water Maze test, the performances of 0.5% and 1% groups were worse than that of the control group ( P < 0.05). The expression of P-tau and Abeta was increased in Pb exposed groups than that of the control group ( P < 0.05). Tau hyper-phosphorylation and Abeta increase in the hippocampus of pups may contribute to the impairment of learning and memory associated with maternal Pb exposure.

Maternal obesity up-regulates inflammatory signaling pathways and enhances cytokine expression in the mid-gestation sheep placenta

Obesity in pregnant women is a growing public health concern. The placenta is a source of cytokines which can induce maternal gestational insulin resistance and alter nutrient transport to the fetus. Obesity induces placental inflammation at term, but the impact of obesity on placental inflammation earlier in pregnancy has not been defined. Using sheep as an experimental model, we hypothesized that maternal obesity (MO) would induce inflammation in the cotyledonary (COT) tissue of the placentome by mid-gestation. Nonpregnant ewes were randomly assigned to a control (C, 100% of NRC recommendations) or obese (OB, 150% of NRC) group from 60 days before conception to 75 day of gestation (dG), when ewes were necropsied and placental COT tissue collected for analyses. Free fatty acids content, triglyceride and cholesterol content were higher (P < 0.05) in the fetal plasma of OB compared to C ewes on day 75. MO increased mRNA levels of toll-like receptor (TLR) 2 (P < 0.05) and TLR4 (P = 0.06), macrophage markers cluster of differentiation (CD)11b (P = 0.06), CD14 and CD68 (P < 0.05), and proinflammatory cytokines tumor necrosis factor (TNF)alpha (P < 0.01), interleukin (IL)-6 (P < 0.05), IL-8(P < 0.01) and IL-18 (P = 0.06), in COT tissue. Inflammatory c-Jun N-terminal kinase (JNK)/c-Jun and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB) signaling pathways were up-regulated (P < 0.05) in COT of OB ewes. In conclusion, MO enhanced the placental inflammatory response in OB ewes at mid-gestation, possibly as a result of increased TLR4 and free fatty acids.

Mouse AMP-activated protein kinase gamma3 subunit R225Q mutation affecting mouse growth performance when fed a high-energy diet

The Rendement Napole (RN) genotype widely exists in Hampshire pigs. Recently, RN gene was identified as a R200Q mutation in AMP-activated protein kinase (AMPK) gamma3 subunit. The effect of RN genotype on the growth performance of animals and the underlying mechanisms remain controversial. Using transgenic mice carrying an analogous R225Q mutation, the objective of this study was to study the role of RN gene in the growth performance of animals at different energy levels. Wild-type (WT) mice and those with the RN mutation were assigned to 4 groups: 1) WT plus normal diet, 2) RN plus normal diet, 3) WT plus high-energy diet, and 4) RN plus high-energy diet. Mice were weaned at 21 d old and fed the trial diets for 1 mo and then killed for carcass measurements. The pH of postmortem muscle from RN mice was less (P < 0.01) than that from WT mice. No difference in growth performance was observed when mice were fed a normal diet. When fed a high-energy diet, RN mice showed a greater fat accumulation (WT vs. RN, 1.11 vs. 1.63 g for gonadal fat and 1.40 vs. 1.84 g for subcutaneous fat; P < 0.05). Muscle weight was also increased (WT vs. RN, 0.27 vs. 0.30 g for gastrocnemius muscle; P < 0.05). The food consumption was greater in RN compared with WT mice (2.95 vs. 2.49 g; P < 0.05). The AMPK content and its downstream target, acetyl-CoA carboxylase (ACC), content were greater in RN mice (P < 0.05). The phosphorylation of ACC at Ser 79, a site exclusively phosphorylated by AMPK, was increased (P < 0.05), showing greater AMPK activity in RN mouse muscle. No difference in muscle fiber composition and mitochondrial content was observed between WT and RN mice. High fat diet downregulates protein kinase B but upregulates extracellular signal-regulated kinase signaling. In conclusion, the R225Q mutation has no major effect on the growth performance of animals fed a normal diet; a high-energy diet increased fatness in RN mice, likely due to their greater consumption of feed compared with WT mice.

Early-life lead exposure affects the activity of TNF-alpha and expression of SNARE complex in hippocampus of mouse pups

This study aims to investigate the effects of maternal lead exposure on learning and memory ability and the protein expression of TNF-alpha and SNARE complex (SNAP-25, VAMP-2, and Syntaxin 1A) in hippocampus of mice offspring. Pb exposure was initiated from beginning of gestation to weaning. Pb acetate administered in drinking solutions was dissolved in distilled deionized water at 0.1%, 0.5%, and 1% groups, respectively. On the PND21, the learning and memory ability of mouse pups was tested by water maze test, and the Pb levels in their blood and hippocampus were also determined. The protein expression of TNF-alpha and SNARE complex in hippocampus was measured by immunohistochemistry and Western blotting. The Pb levels in blood and hippocampus of all exposure groups were significantly higher than control group (P < 0.05). In the water maze test, the performances of 0.5% and 1% groups were worse than that of control group (P < 0.05). The expression of TNF-alpha, Syntaxin 1A, and VAMP-2 was increased in Pb-exposed groups comparing control group (P < 0.05), but the expression of SNAP-25 was decreased (P < 0.05). Up-regulation of TNF-alpha and disturbance of SNARE expression in the hippocampus of pups may contribute to impairment of learning and memory ability associated with maternal Pb exposure.

Molecular characterization, expression and association analysis of the porcine CMYA4 gene with carcass traits

CMYA4 (cardiomyopathy-associated 4) gene plays an important role in thick filament assembly. In this study, we obtained the mRNA sequence including the full coding sequence and the partial 5' untranslated region of the porcine CMYA4 gene by using the rapid amplification of cDNA ends and reverse transcriptase polymerase chain reaction (RT-PCR) and the sequence was deposited in the GenBank nucleotide database (DQ_286571). The human (NM_173167) and mouse (NM_178680) homologues have a 91% and 87% identity with the porcine CMYA4 gene, respectively. The sequence contains an open reading frame encoding 930 amino acid residues, and the amino terminus of the predicted CMYA4 protein contains three tandem repeats belonging to the tetratricopeptide repeat family. Semi-quantitative RT-PCR results showed that the porcine CMYA4 gene is expressed exclusively in striated muscle tissue. An A558G single nucleotide polymorphism in the CMYA4 intron 15 detected as an MspI PCR-restriction fragment length polymorphism showed allele frequency differences among 225 unrelated pigs from six breeds. Association of the genotypes with growth and carcass traits showed that different genotypes of the CMYA4 gene were significantly associated with the backfat thickness of the area between sixth and seventh ribs (p < 0.05) and backfat thickness at the shoulder (p < 0.05).

Molecular characterization and expression pattern of the porcine STARS, a striated muscle-specific expressed gene

STARS (striated muscle activator of Rho signaling) promotes the nuclear localization of MRTFs and mediates SRF transcription, which provides a potential muscle-specific mechanism for linking changes in the actin cytoskeleton structure with muscle gene expression. In this study, the full-length cDNA of the porcine STARS was cloned. The open reading frame of this gene contains 1,155 bp and encodes a protein of 384 amino acids, which is 79, 73, and 77% identical with human, mouse, and rat STARS genes, respectively. RT-PCR revealed that STARS is specifically expressed in heart and skeletal muscles. STARS is also distinctly different in different muscle developmental stages. The result indicates that its expression increased gradually from 33 dpc (days postcoitum) to postnatal muscles, and peaked 28 days postnatal. The porcine STARS was mapped to SSC4p13 using the somatic cell hybrid panel and the radiation hybrid panel IMpRH (LOD score 11.98). The data show that STARS is closely linked to marker SW871. A T/G single nucleotide polymorphism in the coding sequence, detected as Bsh1236I PCR-RFLP, displays allele frequency differences in six pig breeds.

Investigation of Lpin1 as a candidate gene for fat deposition in pigs

Lpin1 deficiency prevents normal adipose tissue development and remarkably reduces adipose tissue mass, while overexpression of the Lpin1 gene in either skeletal muscle or adipose tissue promotes adiposity in mice. However, little is known about the porcine Lpin1 gene. In the present study, a 5,559-bp cDNA sequence of the porcine Lpin1 gene was obtained by RT-PCR and 3'RACE. The sequence consisted of a 111-bp 5'UTR, a 2,685-bp open reading frame encoding a protein of 894 amino acids and a 2,763-bp 3'UTR. Semi-quantitative RT-PCR analysis revealed that Lpin1 had a high level of expression in the liver, spleen, skeletal muscle and fat, a low level of expression in the heart, lung and kidney. The porcine Lpin1 gene was assigned to 3q21-27 by using the somatic cell hybrid panel (SCHP) and the radiation hybrid (IMpRH) panel. One C93T single nucleotide polymorphism (SNP) was identified and genotyped using the TaqI PCR-RFLP method. Association analysis between the genotypes and fat deposition traits suggested that different genotypes of the Lpin1 gene were associated with percentage of leaf fat and intramuscular fat.

AMP-activated protein kinase and adipogenesis in sheep fetal skeletal muscle and 3T3-L1 cells

Marbling, or i.m. fat, is an important factor determining beef quality. Both adipogenesis and hypertrophy of existing adipocytes contribute to enhanced marbling. We hypothesized that the fetal stage is important for the formation of i.m. adipocytes and that AMP-activated protein kinase (AMPK) has a key role in adipogenesis during this stage. The objective of this study was to assess the role of AMPK in adipogenesis in fetal sheep muscle and 3T3-L1 cells. Nonpregnant ewes were randomly assigned to a control (Con, 100% of NRC recommendations, n = 7) or overfed (OF, 150% of NRC, n = 7) diet from 60 d before to 75 d after conception, when the ewes were killed. The fetal LM was collected at necropsy for biochemical analyses. The activity of AMPK was less in the fetal muscle of OF sheep. The expression of peroxisome proliferator-activated receptor (PPAR)gamma, a marker of adipogenesis, was greater in OF fetal muscle compared with Con fetal muscle. To further show the role of AMPK in adipogenesis, we used 3T3-L1 cells. The 3T3-L1 cells were incubated in a standard adipogenic medium for 24 h and 10 d. Activation of AMPK by 5-aminoimidazole-4-car-boxamide-1-beta-d-ribonucleoside dramatically inhibited the expression of PPARgamma and reduced the presence of adipocytes after 10 d of differentiation. Inhibition of AMPK by compound C enhanced the expression of PPARgamma. In conclusion, these data show that AMPK activity is inversely related to adipogenesis in fetal sheep muscle and 3T3-L1 cells.

Periconceptional Nutrient Restriction in the Ewe Alters MAPK/ERK1/2 and PI3K/Akt Growth Signaling Pathways and Vascularity in the Placentome

This study evaluated the role of MAPK/ERK1/2 and/or PI3K/Akt signaling pathways in modulating ovine placentomal vascularity in response to periconceptional maternal nutrient restriction. Ewes were randomly assigned to be nutrient restricted (NR, 50% NRC recommendation, N=7) or control fed (CF, 100% NRC recommendation, N=7) from 60 +/- 2 days before to 30 days after conception (day 0). From day 31 of gestation, all ewes (CF and NR) were fed the control diet until necropsy on day 78. On day 78 of gestation, NR ewes exhibited greater vascularity in both caruncular (CAR) and cotyledon (COT) tissues than CF ewes. Akt or ERK1/2 content in CAR and COT arterial tissue did not differ across dietary treatment. The activated forms, phosphorylated Akt and phosphorylated ERK1/2, were significantly increased in COT but not CAR arterial tissues of NR ewes compared to those of CF ewes (P<0.05). For both CF and NR ewes, phosphorylated Akt and phosphorylated ERK1/2 content in COT are higher (P<0.05) than those in CAR arterial tissues. Immunohistochemical staining revealed cytoplasmic and nuclear localization of Akt, phosphorylated Akt, ERK1/2 and phosphorylated ERK1/2, with phosphorylated Akt and phosphorylated-ERK1/2 specifically localized in trophoblast cells, while binucleate cells remained unstained. In placentomal blood vessels, Akt, phosphorylated Akt, ERK1/2 and phosphorylated ERK1/2 were localized to both endothelium and smooth muscle cells. These findings demonstrate for the first time that periconceptional NR increases vascular density in both COT than CAR tissues of the ovine placentome, and that the MAPK/ERK1/2 and/or PI3K/Akt signaling pathways are increased in NR COT but not NR CAR arterial tissues.

Effect of early gestational undernutrition on angiogenic factor expression and vascularity in the bovine placentome

The effect of early gestation maternal undernutrition followed by realimentation on placentomal vascular growth and angiogenic factor expression was determined in multiparous beef cows bred to the same bull. Cows gestating only female fetuses (n = 30) were fed in equal numbers to meet the NRC requirements (control) or were fed below the NRC requirements to lose BW (nutrient restricted; NR) from d 30 to 125 of gestation. After slaughter on d 125 of gestation, 10 control and 10 NR cows were necropsied. The remaining NR cows (n = 5) were then fed to achieve a BCS equal to their control group contemporaries (n = 5) by d 220 of gestation. All cows were fed the control diet from d 220 until 250 of gestation, when the remaining control and NR cows were slaughtered and necropsied. At necropsy, placentomes were fixed via perfusion of the caruncular and cotyledonary arteries to determine capillary vascular density. Cotyledonary (fetal placental) and caruncular (maternal placental) tissues also were snap-frozen in liquid nitrogen, and mRNA concentrations of vascular endothelial growth factor and its 2 specific receptors, fms-like tyrosine kinase and kinase insert domain containing receptor, as well as placental growth factor, were determined. There was no effect of diet or day of gestation on the percentage of proliferating caruncular cells. Although diet did not impact cotyledonary cellular proliferation, there was an increase (P < 0.05) in the percentage of proliferating cells on d 250 compared with d 125 of gestation. Nutrient restriction from d 30 to 125 increased (P < or = 0.10) placental mRNA concentrations of placental growth factor and fms-like tyrosine kinase; however, there was no alteration in vascularity. By d 250 of gestation, NR cows had increased (P < 0.05) caruncular capillary surface density and decreased (P < 0.05) cotyledonary capillary area density, capillary number density, and capillary surface density compared with control cows. Although nutrient restriction had little effect on placental vascularity by d 125, upon realimentation, alterations in vascularity became apparent by d 250 of gestation, suggesting a placental programming effect.

Leucine stimulates mammalian target of rapamycin signaling in C2C12 myoblasts in part through inhibition of adenosine monophosphate-activated protein kinase1

Mammalian target of rapamycin (mTOR) signaling is one of the main signaling pathways controlling protein synthesis. Leucine treatment upregulates mTOR signaling, which enhances protein synthesis; however, the mechanisms are not well understood. Herein, treatment of C2C12 myoblast cells with leucine enhanced the phosphorylation of mTOR and ribosomal protein S6 kinase. Leucine treatment also decreased the adenosine monophosphate/ATP ratio in myoblasts by 36.4 +/- 9.1% (P < 0.05) and reduced the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) alpha subunit at Thr172 (28.6 +/- 4.9% reduction, P < 0.05) and inhibited AMPK activity (43.6 +/- 3.5% reduction, P < 0.05). In addition, leucine increased the phosphorylation of mTOR at Ser2448 by 63.5 +/- 10.0% (P < 0.05) and protein synthesis by 30.6 +/- 6.1% (P < 0.05). Applying 5-aminoimidazole-4-carbox-amide 1-beta-d-ribonucleoside, an activator of AMPK, abolished the stimulation of mTOR signaling by leucine, showing that AMPK negatively controls mTOR signaling. To further show the role of AMPK in mTOR signaling, myoblasts expressing a dominant negative AMPKalpha subunit were employed. Negative myoblasts had very low AMPK activity. The activation of mTOR induced by leucine in these cells was abated, showing that AMPK contributed to mTOR activation. In conclusion, leucine stimulates mTOR signaling in part through AMPK inhibition. This study implicates AMPK as an important target for nutritional management to enhance mTOR signaling and protein synthesis in muscle cells, thereby increasing muscle growth.

Partial molecular characterization, polymorphism and chromosomal localization of the porcine PSMD4 gene

The complete coding sequence of porcine PSMD4 gene encoding proteasome 26S non-ATPase subunit 4 was obtained by the reverse transcriptase-polymerase chain reaction (RT-PCR) and deposited in GenBank nucleotide database (AY704418). The nucleotide sequence and the predicted protein sequence shared the high sequence identity with their mammalian counterparts. A G/A single nucleotide polymorphism in intron 9 detected as Hin6I PCR-restriction fragment length polymorphism (PCR-RFLP) shows allele frequency differences between Meishan, Erhualian, Tibetan, Large White and Duroc breeds. Analyses of somatic cell hybrid panel (SCHP) and radiation hybrid (IMpRH) panel revealed that PSMD4 gene maps to SSC 4q21-q23 and closely linked the SW512 (14 cR, LOD = 19.47).

Maternal nutrient restriction upregulates growth signaling pathways in the cotyledonary artery of cow placentomes

This study evaluated the role of MAPK/ERK1/2 and/or PI3-K/Akt signaling pathways in modulating bovine placentomal vascularity in response to maternal nutrient restriction. Beef cows were randomly assigned to control fed (Control, n=15, 100% of requirements) or nutrient restricted (NR, n=15, 50% requirements) diets from day 30 to day 125 of gestation. Ten cows from each dietary group were necropsied on day 125 (approximately 45% gestation), and the remaining cows in each diet group were then fed control diets and necropsied on day 250 (approximately 90% gestation). At day 125 of gestation, NR cows exhibited increased (P=0.06) COT vascularity, improved (P<0.05) placentome efficiency (fetal weight/placentomal weight), and increased (P<0.05) phosphorylated Akt and ERK1/2 in COT arteries compared to Control cows. By day 250, however, treatment differences in COT vascularity and phosphorylated Akt and ERK1/2 in COT arteries were lost. On both gestational days, no treatment difference was observed in the levels of phosphorylated Akt or ERK1/2 in CAR arteries. CAR vascularity was similar across treatment on day 125, but tended to be greater (P<0.10) in NR than Control cows on day 250. These data suggest that conceptuses react to an early gestational nutrient restriction by up-regulating COT growth signaling pathways associated with angiogenesis, and that these compensations do not persist to term.

Sequence identification, tissue distribution, mapping and polymorphism of the porcine sar1b gene

The predicted full-length cDNA sequence of the porcine Sar1b gene was characterized by assembling pig ESTs from GenBank. The coding sequence (CDS) shares high sequence identity with the corresponding sequences of human (93%) and mouse (91%). The reverse transcription-polymerase chain reaction (RT-PCR) displayed that porcine Sar1b gene is expressed in all eight tissues (liver, small intestine, stomach, heart, lung, spleen, muscle and fat). Analysis of the somatic cell hybrid panel (SCHP) and the INRA-University of Minnesota porcine radiation hybrid (IMpRH) panel indicated the gene maps to SSC2 (1/2 q24)-q29 and most closely links to the interleukin-4 (IL4) gene. One base-pair deletion polymorphism in the 3' untranslated region (UTR) detected by PCR-single strand conformational polymorphism (PCR-SSCP) analysis shows allele frequency differences between Meishan, Yushan Black, Dahuabai, Qingping, Tibetan, Landrace, Large White and Duroc. The association analysis using pigs of Tongcheng, Landrace x (Large White x Tongcheng) and Large White x (Landrace x Tongcheng) suggested that the deletion polymorphism was associated with the porcine muscle pH value.

Effect of dietary α-lipoic acid on growth, body composition, muscle pH, and AMP-activated protein kinase phosphorylation in mice1

The effects of alpha-lipoic acid (ALA) on the growth, body composition, postmortem AMP-activated protein kinase (AMPK) activation, and 24-h muscle pH were investigated. Thirty male C57BL/6J mice were fed diets containing 0, 0.5, or 1.0% ALA (DM basis). At the end of the 3-wk feeding trial, carcass weights decreased (P < 0.05) 14 and 30% for mice fed 0.5 and 1.0% ALA, respectively, compared with the 0% group, with decreases in BW as the levels of dietary ALA increased. This change in carcass weight occurred because carcass fat content for mice receiving 0.5 and 1.0% ALA was 7.32 and 8.09% lower (P < 0.05), respectively, than for the 0% ALA treatment, and because gonadal fat decreased (P < 0.05) 85% in mice fed 1.0% ALA compared with those fed 0% ALA. Dietary ALA caused a slight increase (P < 0.05) in carcass moisture content, with no (P = 0.07) effect on protein and ash content. Furthermore, ALA supplement decreased (P < 0.05) ADFI (DM basis) from 4.3 g/d for 0% ALA-fed mice to 3.4 g/d for 1.0% ALA-fed mice. At 20 min postmortem, pH was greater (P < 0.05) in muscle of mice fed 1.0% ALA than in muscle of mice fed 0% ALA. Ultimate (24-h) pH values differed (P < 0.05) among treatments, and mean values were 5.83, 6.08, and 6.29 for 0, 0.5, and 1.0% ALA, respectively. Phosphorylation of AMPK alpha subunit at Thr172, an indicator of AMPK activation, was decreased (P < 0.05) in muscle of ALA-treated mice at 20 min postmortem. Because AMPK has a crucial role in the control of glycolysis, the reduction in AMPK activation decreases glycolysis, and thereby increases the ultimate pH of postmortem muscle. In summary, dietary ALA supplement can decrease fat accumulation in mice, and because ALA increased muscle pH at 20 min and 24 h postmortem, these results suggest that dietary ALA supplementation might decrease carcass fatness and prevent the development of PSE pork and poultry. However, further research is required to test the effects of ALA in swine and poultry.

Impact of antimicrobial ingredients and irradiation on the survival of Listeria monocytogenes and the quality of ready-to-eat turkey ham

Irradiation is an effective technology in eliminating Listeria monocytogenes, but it induces quality changes in meat products at or above specific radiation doses. To minimize irradiation-induced quality changes, only low irradiation doses are recommended. However, low-dose irradiation provides a chance for some pathogens to survive and proliferate during prolonged storage. To solve this problem, antimicrobial ingredients [2% sodium lactate (SL), 0.1% sodium diacetate (SDA), 0.1% potassium benzoate (PB)] and low-dose irradiation were combined and tested for their effects on the growth of L. monocytogenes and meat quality. The log10 reductions of L. monocytogenes in hams following exposure to 1.0 to 2.5 kGy of irradiation ranged from 2.0 to 5.0. The D10 values were 0.52 kGy for control ham or ham with PB, SL, or PB + SL; 0.49 kGy for ham with SL+SDA; and 0.48 kGy for ham with PB + SL + SDA (PSS). Addition of SL + SDA or PB + SL in combination with 1.0 kGy of irradiation was effective in suppressing the growth of L. monocytogenes for about 6 wk when stored at 4 degrees C, whereas 2.0 kGy of irradiation was listeriostatic. Ham irradiated with 1 kGy in combination with PSS was listeriostatic throughout storage. SL increased firmness of turkey hams, and sensory panelists noted that the saltiness was a little higher in products containing SL, but its overall impact on quality was minimal. Amounts of benzene were detected in irradiated hams with PB, showing PB was not fit as an antimicrobial ingredient for irradiated foods. In conclusion, 2% SL and 0.1% SDA in combination with low-dose irradiation were effective in ensuring the safety of ready-to-eat meat products against L. monocytogenes.

Effect of nutrient restriction on calpain and calpastatin content of skeletal muscle from cows and fetuses

Calpains are crucial for the degradation of myofibrillar proteins in muscle. Calpastatin is a specific inhibitor of calpains. The objective of this study was to elucidate the effect of nutrient restriction on the activity of calpains and calpastatin in the skeletal muscle of both cows and fetuses. Beginning 30 d after conception, 20 cows were fed either a control diet consisting of native grass hay fortified with vitamins and minerals at recommendations for a mature cow to gain 0.72 kg/d or half the vitamins and minerals and millet straw at 68.1% of NEm requirements. Cows were slaughtered on d 125 of gestation, and the LM was sampled at the 12th rib for calpain and calpastatin measurement. When comparing the muscle samples from nutrient-restricted and control cows, no difference in the activity of calpain I and II was observed; however, there was a significant difference (P < 0.05) in calpastatin activity. Muscle samples from control cows had greater calpastatin content than those of nutrient-restricted cows (P < 0.05); in contrast, the calpastatin content of fetal muscle was greater in fetuses gestated by nutrient-restricted cows than those of control cows (P < 0.05). Further, there were three calpastatin isoforms of 125, 110, and 70 kD detected in fetal muscle, whereas only the110-kD isoform was detected for cow muscle. These results indicate that the activity of the calpain system in skeletal muscle is mainly controlled through the expression of calpastatin. Alternating the calpastatin content in muscle and thereby modulating calpain activity may provide a mechanism for the maintenance of fetal muscle growth during nutrient restriction, whereas skeletal muscle loss in cows is upregulated.

Influence of irradiation and storage on the quality of ready-to-eat turkey breast rolls

Influence of irradiation and storage on the quality of ready-to-eat (RTE) turkey breast rolls was investigated. Commercial oven roasted turkey breast rolls purchased from local stores were sliced and vacuum packaged. The sliced samples were randomly divided into 3 groups and irradiated at 0, 1.0, or 2.0 kGy using a linear accelerator. Color, 2-TBA-reactive substances (TBARS), sensory characteristics, and volatiles were evaluated at 0, 7, and 14 d of storage. Irradiation increased color a* value of turkey breast rolls. Irradiation and storage did not influence TBARS values. Sensory evaluation showed that irradiation significantly increased sulfury flavor. Because a dramatic increase in sulfur compounds was detected in irradiated samples, the sulfury flavor should be due to the sulfur compounds formed during irradiation. Irradiation also increased the amounts of acetylaldehyde, 2-methyl butanal, 3-methyl butanal, benzene, and toluene. It was concluded that irradiation significantly influenced the odor and flavor of RTE turkey breast rolls under vacuum packaging conditions. Therefore, strategies to prevent negative changes in the quality of irradiated RTE turkey breast rolls are needed.

Automated percutaneous lumbar discectomy: a prospective multi-institutional study

PURPOSE

A prospective study in 10 independent hospitals from 1992 to 1994 evaluated automated percutaneous lumbar discectomy (APLD) with a newly designed percutaneous instrument.

MATERIALS AND METHODS

One thousand five hundred eighty-two APLD procedures were performed in 1,525 patients with disc herniation or back pain. Mean follow-up after APLD was 18.3 months. Follow-up of at least 1 year was available in 1,474 patients. One thousand two hundred eighty-nine patients had sciatic pain and 185 had back pain only. Eight hundred twenty-two patients had symptoms for less than 2 years, 652 for more than 2 years. One thousand two hundred sixty-two patients were older than 60 years, 212 were younger than 60 years. Nine hundred fifty patients had disc protrusion, and 357 had sequestration. Forty-eight patients had disc or longitudinal ligament calcification. Twenty-two had previous surgical discectomy. All discectomies were done with use of a straight needle with the patient in the lateral decubitus position.

RESULTS

Success rate (measured by Hijikata's criteria) was 83% at 1 year. Success was significantly greater for protrusion versus sequestration (86% vs 72%, P < .001); for back pain alone versus leg and back pain (89% vs 80%, P < .005); for duration of symptoms less than 2 years versus more than 2 years (85% vs 79%, P < .005); and for age younger than 60 years versus older than 60 years (84% vs 76%, P < .01). Among postsurgical patients, success rate was 77% (17 of 22 patients). The only complication was discitis (0.06%, nine patients). Technical success at L5-S1 was 99% (795 of 800).

CONCLUSION

APLD with Teng's instrument has excellent results. Indications may include back pain alone. A straight needle can be used at L5-S1 in most patients, with proper positioning.

Multilocular cystic renal cell carcinoma. Radiological diagnosis

Multilocular cystic renal cell carcinoma (MCRCC), and its pathological characteristics and roentgenological and B-mode ultrasonographic appearances are described. MCRCC, a special renal carcinoma, can be divided into localized and diffused forms.