The Effects of Open Lung Ventilation on Respiratory Mechanics and Haemodynamics in Atelectatic Infants after Cardiopulmonary Bypass

Acute lung injury (ALI) frequently occurs in infants after cardiopulmonary bypass (CPB) surgery and it sometimes develops into acute respiratory distress syndrome in critically ill infants, which can be life threatening. This study investigated the effects of open lung ventilation on the haemodynamics and respiratory mechanics of 64 infants (34 males; 30 females) with a mean ± SD age of 8.3 ± 0.3 months who developed ALI following CPB surgery. Open lung ventilation significantly improved the respiratory mechanics and oxygenation parameters of the infants, including the partial pressure of oxygen in arterial blood (PaO2), the ratio of PaO2/FiO2 (fraction of inspired oxygen), peak inspiratory pressure, static compliance and airway resistance. It is concluded that open lung ventilation can greatly improve oxygenation and respiratory mechanics in infants with ALI following CPB surgery.

Meta-analysis of the need for nasogastric or nasojejunal decompression after gastrectomy for gastric cancer

BACKGROUND

Nasogastric or nasojejunal decompression has been used routinely to prevent anastomotic leakage, hasten the return of bowel function and shorten hospital stay after gastrectomy for gastric cancer. This meta-analysis evaluates the necessity for such routine decompression.

METHODS

Medline, Embase and The Cochrane Library were searched. Only prospective randomized controlled trials (RCTs) that compared individuals with and without nasogastric or nasojejunal decompression after gastrectomy for gastric cancer were included. Outcomes evaluated were time to flatus, time to starting oral diet, anastomotic leakage, pulmonary complications, length of hospital stay, and morbidity and mortality.

RESULTS

Of 717 patients in five RCTs, 361 were allocated to nasogastric or nasojejunal decompression and 356 to no decompression. Time to oral diet was significantly shorter in the latter group (weighted mean difference 0.43 (95 per cent confidence interval 0.23 to 0.62) days; P < 0.001). Time to flatus, anastomotic leakage, pulmonary complications, length of hospital stay, morbidity and mortality were similar in both groups.

CONCLUSION

Routine nasogastric or nasojejunal decompression is unnecessary after gastrectomy for gastric cancer.

Proteomic analysis of human bone marrow mesenchymal stem cells transduced with human telomerase reverse transcriptase gene during proliferation

OBJECTIVES

Previous studies have reported immortalization and tumorigenicity of human mesenchymal stem cells (hMSCs) transduced with exogenous human telomerase reverse transcriptase (hTERT). We also have established a line of hMSCs transduced with hTERT (hTERT-hMSCs) and we have cultured these cells for 290 population doublings (PDs) during which they demonstrated a large proliferation potential but with no tumorigenicity. The aim of this study was to investigate the protein expression profile of hTERT-hMSCs with two-dimensional gel electrophoresis and peptide mass fingerprinting by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, to be able to analyse the effects of exogenous hTERT on protein expression in hMSCs.

MATERIALS AND METHODS

We generated proteome maps of primary hMSCs and hTERT-hMSCs at PD 95 and PD 275.

RESULTS

A total of 1543 +/- 145 protein spots in gels of primary MSCs at PD 12, 1611 +/- 186 protein spots in gels of hTERT-hMSCs at PD 95 and 1451 +/- 126 protein spots in gels of hTERT-hMSCs at 275 PD were detected. One hundred of these were successfully identified, including 20 which were differentially expressed.

CONCLUSIONS

The results suggest that sustaining levels of prohibitin and p53 expression along with differential expression of proteins in hTERT-hMSCs provide an insight into lack of transforming activity of hTERT-hMSCs during cell proliferation.

Nucleofection is highly efficient for transfecting genes into murine embryonic palatal mesenchymal cells in primary culture

Non-syndromic cleft of the lip and/or palate is one of the most common birth defects in humans. Embryonic palatal mesenchymal (EPM) cells are an attractive source for investigating embryonic palatal development. In this study, we developed a highly efficient transfection method for murine EPM (MEPM) cells. MEPM cells were transfected with the plasmid pEGFP-N1 using two non-viral methods: nucleofection and lipofection. Nucleofection provided a much better rate of gene transfer than lipofection particularly in MEPM cells. The methylenetetrahydrofolate reductase (MTHFR) gene is an important candidate for involvement in the pathogenesis of this birth defect. The RNA interference plasmid of MTHFR was constructed and nucleofected into MEPM cells. Successful transfection resulted in a remarkable reduction in the expression of MTHFR. Taken together, the results indicate that nucleofection is highly efficient for MEPM cell transfection, and that this approach may be useful for investigating gene function in the process of palatogenesis.

High-power efficient diode-pumped Nd:YVO4/LiB3O5 457 nm blue laser with 4.6 W of output power

Continuous-wave 457 blue laser emission at powers as high as 4.6 W is achieved by using a fiber-coupled laser diode array with a power of 30 W to pump 0.1 at. % low-doped bulk Nd:YVO4 crystal, with intracavity frequency doubling in a 15 mm long type I critical phase-matched LiB3O5 (LBO) crystal in a compact three-fold cavity with a length of less than 100 mm. The optical-optical conversion efficiency is greater than 15.3%, and the stability of the output power is better than 3% for an hour.

Increasing the capacity for treatment of chemical plant wastewater by replacing existing suspended carrier media with Kaldnes Moving Bed media at a plant in Singapore

The Kaldnes biomedia K1, which is used in the patented Kaldnes Moving Bed biofilm process, has been tested along with other types of biofilm carriers for biological pretreatment of a complex chemical industry wastewater. The main objective of the test was to find a biofilm carrier that could replace the existing suspended carrier media and at the same time increase the capacity of the existing roughing filter-activated sludge plant by 20% or more. At volumetric organic loads of 7.1 kg COD/m3/d the Kaldnes Moving Bed process achieved much higher removal rates and much lower effluent concentrations than roughing filters using other carriers. The Kaldnes roughing stage achieved more than 85% removal of organic carbon and more than 90% removal of BOD5 at the tested organic load, which was equivalent to a specific biofilm surface area load of 24 g COD/m2/d. Even for the combined roughing filter-activated sludge process, the Kaldnes carriers outperformed the other carriers, with 98% removal of organic carbon and 99.6% removal of BOD5. The Kaldnes train final effluent concentrations were only 22 mg FOC/L and 7 mg BOD5/L. Based on the successful pilot testing, the full-scale plant was upgraded with Kaldnes Moving Bed roughing filters. During normal operation the upgraded plant has easily met the discharge limits of 100 mg COD/L and 50 mg SS/L. For the month of September 2002, with organic loads between 100 and 115% of the design load for the second half of the month, average effluent concentrations were as low as 9 mg FOC/L, 51 mg COD/L and 12 mg SS/L.

Structure characterization of human RalGDS gene, and the identification of its novel variant

RalGDS is a guanine nucleotide dissociation stimulator for Ral, which is a member of the Ras GTPase superfamily that regulates cellular proliferation, differentiation and transformation by mediating multiple signal transduction pathways. RalGDS can specifically promote the conversion from an inactive GDP-bound state to an active GTP-bound state for Ral. The cDNA of human RalGDS has been cloned recently. In this paper, by comparison between the gene's genomic and cDNA seqence, we determined the structure of the gene, which showed that the reported human RalGDS transcribed from 18 exons. Furthermore, a novel variant of RalGDS that codes for a protein with a different N-terminus was cloned and identified. Northern hybridization revealed that the novel transcript was of 6.0 kb in length while the transcript previously reported is of 4.0 kb. Both transcripts were ubiquitously expressed in human adult tissues examined, albeit with different amounts. In addition, this novel transcript was proved to be caused by employment of a new exon, designated as exon 1a, instead of the one, designated as exon 1b, in the reported cDNA. Thus, the RalGDS gene consists of at least 19 exons and spanned a 44 kb region. The length between exon 1a and exon 2 was 33 kb, while the length between exon 1b and exon 2 was 8.8 kb.

Robust structure from motion estimation using inertial data

The utility of using inertial data for the structure-from-motion (SfM) problem is addressed. We show how inertial data can be used for improved noise resistance, reduction of inherent ambiguities, and handling of mixed-domain sequences. We also show that the number of feature points needed for accurate and robust SfM estimation can be significantly reduced when inertial data are employed. Cramér-Rao lower bounds are computed to quantify the improvements in estimating motion parameters. A robust extended-Kalman-filter-based SfM algorithm using inertial data is then developed to fully exploit the inertial information. This algorithm has been tested by using synthetic and real image sequences, and the results show the efficacy of using inertial data for the SfM problem.

Viral and bacterial agents associated with experimental transmission of infectious proventriculitis of broiler chickens

Proventriculitis of broilers can be reproduced by oral inoculation of day-old chicks with a proventricular homogenate from affected 3-wk-old broilers. The objective of the following studies was to isolate from this homogenate viral and bacterial isolates that could produce proventriculitis. A monoclonal antibody to infectious bursal disease virus (IBDV) was used to precipitate virus from the homogenate. A primary chicken digestive tract cell culture system was also used to isolate virus from a 0.2-microm filtrate of the homogenate, and a bacterium was also isolated from the homogenate. In trial 1, day-old birds were orally inoculated with either proventriculus homogenate or monoclonal antibody immunoprecipitated IBDV (MAB-IBDV). At 4, 7, 14, and 21 days postinfection (PI), 12 birds from each treatment group were subjected to necropsy. In trial 2, day-old birds were orally inoculated with either infectious proventriculus homogenate, suspect virus isolated in cell culture and propagated in embryo livers and spleens, or a bacterial isolate. Twelve birds from each treatment were subjected to necropsy at days 7, 14, 21, and 28 PI. In trial 3, treatments were maintained in negative pressure isolation chambers, and an additional treatment included virus plus bacterial isolate. Twenty-four birds from each treatment were subjected to necropsy at day 21 PI. In trial 1, infectious homogenate decreased body weight and relative gizzard weights at 4, 7, 14, and 21 days PI. Proventriculus relative weight was increased at days 7, 14, and 21 PI, and proventriculus lesion scores were increased at days 14 and 21 PI. Bursa/spleen weight ratios were decreased at day 14, and feed conversion was increased at days 4 and 21. The MAB-IBDV treatment decreased proventriculus and gizzard relative weights at day 4 PI, increased proventriculus lesion scores and bursa/spleen weight ratios at day 14, and decreased heterophil/lymphocyte ratios at day 21. In trial 2, all infected birds had significantly higher mean relative proventriculus weights at 21 days PI and had higher 4-wk mean proventriculus scores as compared with both control groups. In trial 3, birds treated with homogenate and birds treated with both suspect virus and the bacterial isolate had significantly higher proventriculus lesion scores; higher relative weights of proventriculus, gizzard, liver, and heart; lower body weights; and lower relative bursa weights compared with the saline control group. These studies suggest that infectious proventriculitis has a complex etiology involving both viral and bacterial infection.

Cell proliferation in cancer prevention; effects of preventive agents on estrogen-related endometrial carcinogenesis model and on an in vitro model in human colorectal cells

Proto-oncogenes such as c-fos, c-jun and c-myc are known to relate to cell proliferation and differentiation. Some oriental herbal medicines like Glycyrrhizae radix or Juzen-taiho-to were found to suppress estradiol-17 beta (E2)-induced expression of c-fos/jun in uterine corpus and inhibited N-methyl-N-nitrosourea and E2-induced endometrial carcinogenesis in mice. It is suggested that the effects of such oriental drugs are exerted probably through suppression of estrogen-induced c-fos/jun expression and they are promising preventing agents for endometrial cancers. In the combined in vitro assay for cell proliferation (MTS assay) and apoptosis (DNA fragmentation) in human colorectal cancer cells (Colo 320), a number of naturally occurring chemopreventive agents such as curcumin, quercetin, auraptene, 1'-acetoxychavicol acetate (ACA) and indole-3-carbinol were shown to generate apoptosis as well as to inhibit cell proliferation. The results suggest a mode of action of these chemopreventive agents and also imply that such in vitro short term assay is useful for detection of new agents for cancer prevention.

Bioactivity of bioresorbable osteosynthetic devices made of hydroxyapatite/poly-DL-lactide composites: an experimental study

AIM

To investigate the bioactivity of the self-designed biodegradable osteosynthetic devices made of resorbable hydroxyapatite microparticles/poly-DL-lactide (HA/PDLLA) composites.

METHOD

Forty-three rabbits with a transverse transcondylar osteotomy of the distal femur were fixed intramedullary by a HA/PDLLA rod, the duration of follow-up were 3, 6, 12, 24 and 36 weeks. Histological, scanning electron microscopic (SEM), energy dispersive X-ray (EDX) and biomechanical analyses were done.

RESULTS

Active new bone formation and direct bone-bonding were seen at the bone-implant interface. Generous apatite crystals deposited and grew on the surface of the composites at 3 approximately 6 weeks postoperation. The interfacial shear strength increased significantly.

CONCLUSION

Through the incorporating of resorbable HA microparticles, specific bone-bonding and active osteogenic capacity is introduced. This kind of bioactivity, together with other properties such as sufficient mechanical strength, enhanced biocompatibility and radiopacity, which are intrinsically unobtainable in totally resorbable polymer/polymer systems, make the HA/PDLLA composites become a desirable material for the internal fixation of cancellous bone.

On the dispersion index of a Markovian molecular clock

The number of nucleotide substitutions accumulated in a gene or in a lineage is an important random variable in the study of molecular evolution. Of particular interest is the ratio of the variance to the mean of that random variable, often known as the dispersion index. Because nucleotide substitution is most commonly modeled by a continuous-time four-state Markov chain, this paper provides a systematic method of computing the dispersion indices exhibited by a continuous-time four-state Markov chain. Using this method along with computer algebra and Monte Carlo simulation, this paper offers partially proven conjectures that were supported by thorough computer experiments. It is believed that the Tamura model, the equal-input model and the Takahata-Kimura model always exhibit dispersion indices less than 2. It is also believed that a general four-state model can be chosen to exhibit a dispersion index of any desired magnitude, although the chance of a randomly chosen such model exhibiting a dispersion index greater than 2 is as small as about 2%. Relevance of these findings to the neutral theory is discussed.

Fargosides A-E, triterpenoid saponins from Holboellia fargesii

Five new triterpenoid saponins, fargosides A, B, C, D, and E, were isolated from the roots of Holboellia fargesii. The structures of fargosides A-E were elucidated on the basis of chemical and physicochemical evidence and found to be 3beta,20alpha-dihydroxy-29-norolean-12-en-28-oic acid 3-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (1), 3beta,20alpha,24-trihydroxy-29-norolean-12-en-28-oic acid 23-O-beta-D-fucopyranosyl-(1-->2)-[alpha-L-arabinopyranosyl-(1-->3)]-beta-D-glucopyranoside (2), 3beta,23-dihydroxy-30-norolean-2,20(29)-dien-28-oic acid 3-O-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-glucopyranosyluronic acid-(1-->3)]-alpha-L-arabinopyranoside (3), 3beta,23-dihydroxy-30-norolean-12,20(29)-dien-28-oic acid 3-O-methyl beta-D-glucopyranosyluronate-(1-->3)-alpha-L-arabinopyranoside (4), and 3beta,23-dihydroxy-olean-12-en-28-oic acid 3-O-methyl beta-D-glucopyranosyluronate-(1-->3)-alpha-L-arabinopyranoside (5), respectively.

A new unusual iridoid with inhibition of activator protein-1 (AP-1) from the leaves of Morinda citrifolia L

[structure in text] From the leaves of Morinda citrifolia, a new unusual iridoid, named citrifolinoside (1), showing significant inhibition of UVB-induced Activator Protein-1 (AP-1) activity in cell cultures, has been isolated. Its structure was elucidated on the basis of detailed high-field 1D and 2D spectral analysis.

A double-labeled preparation for simultaneous measurement of [3H]-noradrenaline and [14C]-glutamic acid exocytosis from streptolysin-O (SLO)-perforated synaptosomes

We have developed a novel method to examine [3H]-noradrenaline and [14C]-glutamate release from the same sample of streptolysin-O (SLO) perforated rat cortical synaptosomes. Ca2+ -dependent [3H]-noradrenaline and [14C]-glutamate release was examined at different temperatures and was found to be greater at 30 degrees C than at 25 degrees C. Ca2+ -dependent release of [3H]-noradrenaline is more ATP dependent than Ca2+ -dependent release of [14C]-glutamate. No significant reuptake of either neurotransmitter by the perforated synaptosomes was detected, indicating all the synaptosomes were indeed perforated. Incubations with 1 mM ouabain, a specific Na+,K+ -ATPase inhibitor, slightly increased Ca2+ -dependent release of both neurotransmitters. [3H]-noradrenaline is released from large dense-core vesicles and [14C]-glutamate is released from small clear synaptic vesicles, so one can directly compare and contrast neurotransmitter release mechanisms between large dense-core vesicles and small clear synaptic vesicles using this preparation.

Effect of a rippling mode on resonances of carbon nanotubes

A recent study determined the Young's modulus of carbon nanotubes by measuring resonance frequency and using the modulus-frequency relation resulting from the linear vibration theory. It leads to the report that the Young's modulus decreases sharply, from about 1 to 0.1 TPa with the diameter D increasing from 8 to 40 nanometers, and the investigators attributed this decrease to the emergence of an unusual bending mode during the measurement that corresponds to rippling on the inner arc of the bent nanotubes. The nonlinear analysis presented in this paper that captures the rippling mode suggests that the effective Young's modulus can indeed decrease substantially with increasing diameter, and that the results from the classical linear theory may be invalid in such measurements.