Up-regulation of the Ang II/AT1 receptor may compensate for the loss of gastric antrum ICC via the PI3k/Akt signaling pathway in STZ-induced diabetic mice

The classic renin-angiotensin system (RAS) is a complex system in which angiotensin II (Ang II) has been identified as an important endogenous regulator that influences both smooth muscle contraction and cell growth. Although a local RAS is known to exist in the gastrointestinal tract, it is unclear whether Ang II is involved in the loss of gastric interstitial cells of Cajal (ICC) in diabetic mice. The present study was designed to investigate the effect of Ang II on ICC survival in streptozotocin (STZ)-induced diabetic mice. Western blot, immunofluorescence, isometric muscle recording, enzyme-linked immunosorbent assay (ELISA) and a cell counting kit-8 were used in this research. Our results demonstrate that the c-Kit and membrane-bound stem cell factor (mSCF) protein expression levels in gastric smooth muscle were decreased in STZ-induced diabetic mice. However, the angiotensin receptor type 1 (AT1R) expression levels in gastric smooth muscle and angiotensin-converting enzyme (ACE) expression levels in gastric mucosa were increased. The effect of Ang II on the tonic contraction of gastric smooth muscle was potentiated in diabetic mice, and the plasma Ang II level was enhanced. Ang II increased mSCF expression, cell proliferation, and Akt-Ser473 phosphorylation in cultured gastric smooth muscle cells (GSMCs). These effects were reduced by specific inhibitors ZD7155 (an AT1R antagonist) and LY294002 (a PI3-kinase inhibitor). Our results suggest that Ang II increases mSCF expression and cell proliferation in cultured GSMCs in a PI3K/Akt signaling-dependent manner. ACE and AT1R up-regulation in the stomach may help compensate for ICC loss in STZ-induced diabetic mice.

Evaluation of Relative Bioavailability of 25-Hydroxycholecalciferol to Cholecalciferol for Broiler Chickens

This study was conducted to evaluate the relative bioavailability (RBV) of 25-hydroxycholecalciferol (25-OH-D₃) to cholecalciferol (vitamin D₃) in 1- to 21-d-old broiler chickens fed with calcium (Ca)- and phosphorus (P)-deficient diets. On the day of hatch, 450 female Ross 308 broiler chickens were assigned to nine treatments, with five replicates of ten birds each. The basal diet contained 0.50% Ca and 0.25% non-phytate phosphorus (NPP) and was not supplemented with vitamin D. Vitamin D₃ was fed at 0, 2.5, 5.0, 10.0, and 20.0 μg/kg, and 25-OH-D₃ was fed at 1.25, 2.5, 5.0, and 10.0 μg/kg. The RBV of 25-OH-D₃ was determined using vitamin D₃ as the standard source by the slope ratio method. Vitamin D₃ and 25-OH-D₃ intake was used as the independent variable for regression analysis. The linear relationships between the level of vitamin D₃ or 25-OH-D₃ and body weight gain (BWG) and the weight, length, ash weight, and the percentage of ash, Ca, and P in femur, tibia, and metatarsus of broiler chickens were observed. Using BWG as the criterion, the RBV value of 25-OH-D₃ to vitamin D₃ was 1.85. Using the mineralization of the femur, tibia, and metatarsus as criteria, the RBV of 25-OH-D₃ to vitamin D₃ ranged from 1.82 to 2.45, 1.86 to 2.52, and 1.65 to 2.05, respectively. These data indicate that 25-OH-D₃ is approximately 2.03 times as active as vitamin D₃ in promoting growth performance and bone mineralization in broiler chicken diets.

First Report of Cucumber mosaic virus in Agastache rugosa in China

Agastache rugosa (family Lamiaceae) is one of the most common herbs of traditional Chinese medicine in China, and the species increasingly gains popularity on the international market. In June 2012, typical mosaic symptoms were observed on many A. rugosa plants in a field in Shanxi Province. The incidence of this disease reached more than 60% in a 2.6-ha field. Seven symptomatic plants were tested by DAS-ELISA using monoclonal antibodies specific for Tobacco mosaic virus (TMV), Cucumber mosaic virus (CMV), and Tomato mosaic virus (ToMV); all antisera used in DAS-ELISA were generated and validated in our laboratory. CMV was found in all seven samples tested, but not TMV and ToMV. Double-stranded RNAs (dsRNA) extracted from infected leaves were used as templates in the subsequent two-step RT-PCR reaction (1). In order to further confirm the presence of CMV, a pair of specific primers (forward: 5'-ACGTCGACCATGGACAAATC-3', and reverse: 5'-TACCCGGGTCAGACTGGTAGCACC-3') based on the coat protein gene sequence of CMV were used to amplify PCR products of the expected size (657 bp) from ELISA-positive samples (2). These PCR products were cloned into pUCm-T Vector (Sangon Biotech, Shanghai) and sequenced. Five independent clones have been sequenced to obtain the consensus sequence. This consensus sequence (GenBank Accession No. JQ403529) was compared with other CMV sequences available in GenBank using DNAMAN. The partial CMV coat protein sequence showed the highest 97.9% nucleotide identity with a subgroup IB CMV isolate from China (DQ459481). To our knowledge, this is the first report of the natural occurrence of CMV on A. rugosa. References: (1) M. Krajacić et al. J. Chromatogr. A. 1144:111, 2007. (2) F. Li et al. J. Zhejiang Univ. 26:261, 2000.

Effects of dietary lysine levels on apparent nutrient digestibility and serum amino Acid absorption mode in growing pigs

Two experiments were conducted to determine the effects of different dietary lysine levels on the apparent nutrient digestibility, the serum amino acid (AA) concentration, and the biochemical parameters of the precaval and portal vein blood in growing pigs. In Experiment 1, 15 noncannulated pigs received diets with different lysine densities (0.65%, 0.95%, and 1.25% lysine) for 13 d. A total collection digestion test was performed, and blood samples were collected from the precaval vein at the end of the experiment. In Experiment 2, four cannulated pigs were fed the same diets of Experiment 1. The experiment used a self-control experimental design and was divided into three periods. On d 5 of each period, at 0.5 h before feeding and hourly up to 8 h after feeding, single blood samples were collected from catheters placed in the portal vein. In Experiment 1, some serum AAs (including lysine), serum urinary nitrogen (SUN), and total protein (TP) concentrations were significantly affected by the dietary lysine levels (p<0.05). Moreover, the 0.65% lysine treatment showed a significant lower apparent digestibility of gross energy, dry matter, crude protein, and phosphorus than the other treatments (p<0.05). In Experiment 2, serum lysine, histidine, phenylalanine, threonine, valine, isoleucine (p = 0.0588), triglyceride, and SUN (p = 0.0572) concentrations were significantly affected by the dietary lysine levels (p<0.05). Additionally, almost all of the determined serum AA and total AA concentrations reached their lowest values at 0.5 h before feeding and their highest values at 2 h after feeding (p<0.05). These findings indicate that the greatest absorption of AA occurred at 2 h after feeding and that the dynamic profile of serum AA is affected by the dietary lysine levels. Moreover, when the dietary lysine content was 0.95%, the growing pigs achieved a better nutrient digestibility and serum metabolites levels.

[Near infrared distance sensing method for Chang'e-3 alpha particle X-ray spectrometer]

Alpha particle X-ray spectrometer (APXS) is one of the payloads of Chang'E-3 lunar rover, the scientific objective of which is in-situ observation and off-line analysis of lunar regolith and rock. Distance measurement is one of the important functions for APXS to perform effective detection on the moon. The present paper will first give a brief introduction to APXS, and then analyze the specific requirements and constraints to realize distance measurement, at last present a new near infrared distance sensing algorithm by using the inflection point of response curve. The theoretical analysis and the experiment results verify the feasibility of this algorithm. Although the theoretical analysis shows that this method is not sensitive to the operating temperature and reflectance of the lunar surface, the solar infrared radiant intensity may make photosensor saturation. The solutions are reducing the gain of device and avoiding direct exposure to sun light.

[Temperature effect correction for Chang'E-3 alpha particle X-ray spectrometer]

Alpha particle X-ray spectrometer (APXS) is one of the payloads of Chang'E-3 lunar rover of China's Lunar Exploration Project. The present paper introduces briefly the components of APXS, how it works and its working environment on the lunar surface. The environmental temperature effect has been studied with simulations and experiments, and the results show that the temperature of the APXS sensor will be varying during the measuring on the lunar surface. And another experiment reveals that the energy resolution becomes worse if the sensor's temperature is varying. In this paper, a correction method based on Pearson's chi-squared test is presented. The method can improve the energy resolution when the sensor's temperature is varying. We have tested the method with the spectra acquired by APXS in the temperature varying period of Temperature Cycling Test, and the results show that the method is efficient and reliable.

Dentin regeneration using deciduous pulp stem/progenitor cells

Reparative dentin formation is essential for maintaining the integrity of dentin structure during disease or trauma. In this study, we investigated stem/progenitor cell-based tissue engineering for dentin regeneration in a large animal model. Porcine deciduous pulp stem/progenitor cells (PDPSCs) were mixed with a beta-tricalcium phosphate (β-TCP) scaffold for dentin regeneration. Different concentrations of PDPSCs were tested to determine the optimal density for dentin regeneration. Aliquots of 5×10(5) PDPSCs in 1 mL resulted in the highest number of cells attached to the scaffold and the greatest alkaline phosphatase activity. We labeled PDPSCs with green fluorescent protein (GFP) and used the optimal cell numbers mixed with β-TCP to repair pulp chamber roof defects in the premolars of swine. Four weeks after transplantation, GFP-positive PDPSCs were observed in PDPSC-embedded scaffold constructs. At 16 weeks after transplantation, the PDPSCs mixed with β-TCP significantly regenerated the dentin-like structures and nearly completely restored the pulp chamber roof defects. This study demonstrated that the PDPSC/scaffold construct was useful in direct pulp-capping and provides pre-clinical evidence for stem/progenitor cell-based dentin regeneration.

Genetic diversity of mitochondrial cytochrome b gene in Chinese native buffalo

The origins of the domestic water buffalo remain contentious. To better understand the origins of Chinese water buffalo, we sequenced the complete mitochondrial cytochrome b (MT-CYB) gene from 270 individuals representing 13 Chinese domestic swamp buffalo populations. We found genetic evidence of introgression of river buffalo into Chinese swamp buffalo herds. Swamp buffalo haplotypes can be divided into two highly divergent lineages (A and B), suggesting that Chinese native swamp buffalo have two maternal origins. We found that the A→G transition in the buffalo MT-CYB gene stop codon resulted in buffalo haplotypes being terminated by one of two stop codons: AGA or AGG. AGA is common to river buffalo and lineage A of swamp buffalo, while AGG is specific to lineage B of swamp buffalo. Lineage A appears to have been domesticated in China. Further genetic evidence is required to clarify the origins of lineage B.

Over-expression of NYGGF4 (PID1) inhibits glucose transport in skeletal myotubes by blocking the IRS1/PI3K/AKT insulin pathway

INTRODUCTION

Defects in insulin-stimulated glucose uptake in muscle are the important early events in the pathogenesis of insulin resistance. NYGGF4 (also named PID1) is a recently discovered gene which is suggested to be associated with obesity-associated insulin resistance. In this study, we aimed to investigate the effects of NYGGF4 on glucose uptake and insulin signaling in rat skeletal muscle cells.

METHODS

Rat L6 myoblasts were transfected with either an empty vector or an NYGGF4-expressing vector and induced to differentiate into mature L6 skeletal myotubes. Glucose uptake was determined by measuring uptake of 2-deoxy-d-[(3)H] glucose. Immunoblotting was performed to detect the translocation of insulin-sensitive glucose transporter 4 (GLUT4). Immunoblotting was also used to measure phosphorylation and total protein levels of the insulin signaling proteins including insulin receptor (IR), insulin receptor substrate 1 (IRS1), Akt, extracellular signal-regulated kinase 1 and 2 (ERK1/2), p38, and c-Jun-N-terminal kinase (JNK).

RESULTS

NYGGF4 over-expression in L6 skeletal myotubes reduced insulin-stimulated glucose uptake and impaired insulin-stimulated GLUT4 translocation. It also diminished insulin-stimulated tyrosine phosphorylation of IRS1 and serine phosphorylation of Akt without affecting the phosphorylation of IR, ERK1/2, p38, or JNK.

CONCLUSIONS

Over-expression of NYGGF4 inhibits glucose transport in skeletal myotubes by blocking the IRS1/PI3K/AKT insulin pathway. These observations highlight the potential role of NYGGF4 in glucose homeostasis and the development of insulin resistance in obesity.

Simultaneous detection of enteric bacteria from surface waters by QPCR in comparison with conventional bacterial indicators

A rapid quantitative polymerase chain reaction (QPCR) method was developed for simultaneous detection of enteric bacteria from surface waters by utilizing a pair of universal primers which targeted four bacteria strains, namely Shigella dysenteriae, Vibrio cholerae, Salmonella typhimurium, and Escherichia coli. It was estimated that the QPCR method had a 94% confidence, and a detection limit as 2.7 E. coli cells per sample in undiluted DNA extracts. The QPCR method was applied for the bacteriological examination of several surface waters in the urban area of Xi'an, China and comparison was made with the conventional bacteria indicators determined by conventional membrane filter (MF) method. As a result, the calibrator cell equivalents (CCE) determined by QPCR was 2.2 to five times of the total coliform CFU, and the characteristics of the bacterial quality of different waters could be well presented by the QPCR results with a higher sensitivity. The coefficient of variation (CV) of data obtained by QPCR was smaller than that by traditional MF method, indicating a more stable analysis result. The QPCR method could thus be used as a supplement of the conventional culture method for more sensitive detection of pathogenic enteric bacteria from water.

Stem cells from deciduous tooth repair mandibular defect in swine

Stem cells from human exfoliated deciduous teeth have been identified as a new post-natal stem cell population with multipotential differentiation capabilities, including regeneration of mineralized tissues in vivo. To examine the efficacy of utilizing these stem cells in regenerating orofacial bone defects, we isolated stem cells from miniature pig deciduous teeth and engrafted the critical-size bone defects generated in swine mandible models. Our results indicated that stem cells from miniature pig deciduous teeth, an autologous and easily accessible stem cell source, were able to engraft and regenerate bone to repair critical-size mandibular defects at 6 months post-surgical reconstruction. This pre-clinical study in a large-animal model, specifically swine, allows for testing of a stem cells/scaffold construct in the restoration of orofacial skeletal defects and provides rapid translation of stem-cell-based therapy in orofacial reconstruction in human clinical trials.

Characteristics of bacterial and viral contamination of urban waters: a case study in Xi'an, China

In order to gain knowledge on the presence of bacteria and viruses in urban waters, the authors started a long-term study on the microbiological quality of urban lakes and rivers in Xi'an, China. In the current study, enteroviruses were chosen as typical viruses and RT-nested PCR was conducted for their detection. Universal primers were designed for simultaneous detection of poliovirus, coxsackievirus, and enterovirus 71 which are the most frequently encountered enteroviruses in China. The RT-nested PCR protocol established in this study showed high sensitivity and specificity. The detection limit was equivalent to 0.038 CCID50 per litre by applying a modified adsorption-elution concentration method. No cross-reactivity was observed using the genome of pathogenic bacteria as of PCR template. The occurrence of enteroviruses was compared with fecal coliform count in a 6-month period from July to December 2006 for the urban waters. As a result, it was noticed that the presence of enteroviruses might not relate to the fecal coliform count so much. Statistical analysis also indicated that there was no significant correlation between the presence of enteroviruses and that of total bacteria, total coliform, and fecal coliform.

A comparative study of one-level and two-level semiparametric estimation of hemodynamic response function for fMRI data

Functional magnetic resonance imaging (fMRI) is emerging as a powerful tool for studying the process underlying the working of the many regions of the human brain. The standard tool for analyzing fMRI data is some variant of the linear model, which is restrictive in modeling assumptions. In this paper, we develop a semiparametric approach, based on the cubic smoothing splines, to obtain statistically more efficient estimates of the underlying hemodynamic response function (HRF) associated with fMRI experiments. The hypothesis testing of HRF is conducted to identify the brain regions which are activated when a subject performs a particular task. Furthermore, we compare one-level and two-level semiparametric estimates of HRF in significance tests for detecting the activated brain regions. Our simulation studies demonstrate that the one-level estimates combined with a bias-correction procedure perform best in detecting the activated brain regions. We illustrate this method using a real fMRI data set and compare it with popular methods offered by AFNI and FSL.

[Comparison of several rib rings with intercostal muscles for tracheal replacement in dogs]

OBJECTIVE

To compare the effect of several types of rib rings with intercostal muscles for the replacement of trachea in thorax.

METHODS

The surface layer of the third rib of dogs were ripped off and curved into triangular, quadrilateral and polygonal form. These three types of rib rings with intercostal muscles were used to replace a segment of trachea in thorax.

RESULTS

The stability of triangular rib ring was very well, but stricture of ring were often happened because of its smaller internal diameter. These stability of quadrilateral rib ring was the worst. The polygonal rib ring presented the biggest diameter and good stability compared to the other two kinds of rings. If silicone tube was supplemented in the polygonal rib ring, the quality of artificial trachea was excellent.

CONCLUSION

The rib rings with intercostal muscles are successfully used for replacing the defect of trachea in canine thorax. The polygonal rib rings have the best quality in the three types of rib ring for tracheal replacement.

Suitability of immobilized metal affinity chromatography for protein purification from canola

This work demonstrates that proper selection of a metal ion and chelating ligand enables recovery of a his(6)-tagged protein from canola (Brassica napus) extracts by immobilized metal affinity chromatography (IMAC). When using Co(2+) with iminodiacetate (IDA) as the chelating ligand, beta-glucuronidase-his(6) (GUSH6) can be purified from canola protein extract with almost homogeneous purity in a single chromatographic step. The discrimination with which metal ions bound native canola proteins followed the order Cu(2+) < Ni(2+) < Zn(2+) < Co(2+) in regard to elimination of proteins coeluted with the fusion protein. IDA- and nitrilotriacetate (NTA)-immobilized metal ions showed different binding patterns, whose cause is attributed to a more rigid binding orientation of the his(6) in forming a tridentate with Me(2+)-IDA than in forming a bidentate with Me(2+)-NTA. The more flexible binding allows for multisite interactions over the protein.

[Enzymehistochemical and immunohistological changes of skeletal muscle motor end-plates and muscle fibers and their relation to the time of death]

In order to investigate the relationship between the retrograde changes of the skeletal muscle and the time of death in various postmortem intervals (PMI), a systemic study of the enzymehistochemical activity of AChE, SDH, LDH, Ca(2+)-ATPase and the immunohistochemical reaction of SYN in motor end-plates and muscle fibers was conducted in rats under different temperatures and at various PMI. The results were analyzed and compared by an image processing system. It was found that these changes were related to the PMI, especially AChE changes. The AChE could be used as a sign-enzyme of skeletal muscle to date death.

Minimally invasive cryosurgery--technological advances

The technological advances which have caused renewed interest in cryosurgery are the development of intraoperative ultrasound to monitor the therapeutic process and the development of new cryosurgical equipment designed to use supercooled liquid nitrogen. The thin, highly efficient probes, available in several sizes, can be placed in diseased sites via endoscopy or percutaneously in minimally invasive procedures. The manner of use is to place the probe in the desired location in the diseased tissue with ultrasound guidance. If required by the size or location of the tumor, as many as five probes can be inserted and cooled to -195 degrees C simultaneously. The process of freezing is monitored by ultrasound which displays a hypoechoic (dark) image when the tissue if frozen. Rapid freezing, slow thawing, and repetition of the freeze/thaw cycle are standard features of technique. Clinical applications which have become common in the past 4 years include the treatment of prostatic cancer and liver tumors. The cases selected for cryosurgery are generally those for which no conventional treatment is possible. However, especially in prostatic cancer, the operative morbidity is so low and the results of therapy are sufficiently good in the short term to merit consideration of use in earlier stages of the disease. Diverse tumors in other sites, such as the brain, bronchus, bone, pancreas, kidney, and uterus, have also been treated in small numbers by cryosurgery. Judging from this experience, further expansion in the use of cryosurgical techniques seems certain.

[Clinical and experimental study of yangxueshengru oral liquor in promoting puerperal breast milk secretion]

Applying Yangxueshengru Oral Liquor (YXSR) to treat 103 cases of puerperal insufficient lactation. Six hours after delivery, the parturient took YXSR, its effective rate was 98.06%. The results revealed that it could improve breast milk secretion significantly and increase daily lactation amount of parturient, insufficient lactation rate was reduced. The content of protein and trace elements (Fe, Zn and Mn, etc) in colostrum increased, the difference between medicated group and control group was significant (P < 0.05-0.001). Animal experiment showed that YXSR could increase the response of prolactin (PRL) level of model rats (P < 0.01), the serum, PRL and cortisol level of the rats were also raised significantly (P < 0.01).

Characteristics and developmental changes of some plasma nutrition metabolites in neonatal lambs

Twelve spontaneously delivered Hu sheep neonatal lambs with a birth weight of 1.5-4.5 kg were used to study the characteristics and developmental changes of plasma nutrition metabolites during postnatal period in 7 days of age. The results showed that plasma glucose (Glu) concentration rose significantly within 4 h after lambing and then maintained a fluctuent upward tendency until day 7 of age. Fructose (Fru) and lactic acid (LA) concentrations were highest at 1 h after birth, tended to drop thereafter, and remained relatively stable levels after day 3 of age. Free fatty acid (FFA) tended to increase within 12 h after birth, followed by keeping comparatively high levels although decreasing fluctuently. An obvious increase of total protein (TP) occurred within 8 h after birth and then remained a relatively high concentration until day 7 of age. a-Amino nitrogen (a-NH2N) tended to rise by 4 h and fell slightly thereafter, urea nitrogen (UN) had an elevated concentration from birth to 8 h and then dropped obviously. Both a-NH2N and UN appeared to be fairly stable during the first week of age in neonatal lambs.

Chromatin and nucleosome organizations and DNA replication of nucleus reassembled in vitro using purified exogenous DNA and Xenopus egg extracts

It has been demonstrated in the last ten years that the nuclear reassembly may occur in the cell-free systems from frog egg extracts added with exogenous naked DNA. However, there remains an open question: is the cell-free reassembled nucleus structurally similar to the nucleus in the intact cell? That is, does the cell-free reassembled nucleus contain nucleosomes and chromatin? For this issue, we have designed experiments for identifying the internal structures of the cell-free reassembled nucleus. These experiments show that the nucleus reassembled in vitro also contains chromatin which is composed of typical 10 nm nucleosome fibers of "beads-on-a-string", 30 nm filaments and the next higher-order structures. The digestion experiment with the enzyme micrococcal nuclease has demonstrated that the DNA in the nucleosome of the reconstituted chromatin is about 200 base pairs (bp) in length, of which 165 bp may be in the nucleosome particle, and 35 bp may be in the linker between two particles. Prolonging digestion of the 165-bp particle DNA fragment will yield a 146-bp fragment, which may be wounded in the nucleosome core. Experiments also provide evidence that the chromatin reconstitution in the cell-free reassembled nucleus is a progressive process, and that the nucleus can replicate its DNA. Based on these observations, we suppose that the chromatin of the cell-free reassembled nucleus may be structurally and functionally similar to the chromatin of the intact cells.

[Nuclear reconstitution around purified HeLa chromosomes in a cell-free system from Xenopus eggs]

Activated Xenopus egg extracts are capable of reconstituting nucleus around the added DNA or chromatin. To understand better the nuclear reconstitution process and the structure of the assembled nucleus, we have developed a cell-free system using activated Xenopus egg extracts and metaphase chromosomes of HeLa cells. We demonstrate that the extracts are efficient promoting the decondensation of the metaphase chromosomes and the nuclear reconstitution around the chromosomes, and that the nuclear reconstitution is a precise process. The reassembled nucleus possesses a typical nuclear envelope, pore complexes, nuclear lamina, nuclear matrix, chromatin, etc., as shown by electron microscopy, embedment and embedment-free electron microscopy, and immunofluorescence method. We also found that the annulate lamellae directly take part in nuclear envelope and pore complex reconstitution by fusing with the double membrane, having reassembled on the surface of chromatin/chromosomes.

[Repair of ruptured aneurysm of aortic sinus by sandwiching technique]

Nine cases of ruptured aneurysm of aortic sinus were successfully repaired by sandwiching technique. The abnormalities consisted of VSD (7 patients) and moderate aortic regurgitation (2). Their cardiac chest ratio was > 65%, and cardiac function was III-IV (NYHA). Follow-up showed that their cardiac murmur and thrill disappeared and cardiac function increased to I-II (NYHA). This technique is superior to others.