[Influence of different inner dressings in negative-pressure wound therapy on escharectomy wound of full-thickness burn rabbits]

Objective: To explore the influence of different inner dressings in negative-pressure wound therapy (NPWT) on escharectomy wound of full-thickness burn rabbits. Methods: Eighteen Japanese white rabbits were inflicted with full-thickness burn on unilateral back. They were divided into polymer dressing group (PD), biological dressing group (BD), and silver biological dressing group (SBD), according to the random number table, with 6 rabbits in each group. On 3 days post burn, the wounds were performed with escharectomy, and then wounds of rabbits in group PD were covered with polyurethane foam. Wounds of rabbits in group BD were covered with porcine acellular dermal matrix (ADM) and wounds of rabbits in group SBD were covered with silver porcine ADM. Then continuous NPWT was performed on rabbits of the three groups for 7 days. Immediately after surgery and on post surgery day (PSD) 7, general observation of wound was conducted and tissue around the wound was harvested for determination of dry to wet weight ratio. The content of bacteria was counted and the content of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 in wound was determined by enzyme-linked immunosorbent assay. Fibroblasts in wound were counted after Masson staining and number of microvessels was counted after CD31 antibody immunohistochemical staining. Data were processed with analysis of variance for repeated measurement, LSD-t test, paired samples t test, and Bonferroni correction. Results: (1) Immediately after surgery, there was no granulation tissue in basal wound of rabbits in the three groups, with rich blood supply and obvious edema. On PSD 7, much granulation tissue was found in basal wound of rabbits in the three groups, with no or mild edema and no obvious redness and swelling in wound edge. (2) There were no significant differences in dry to wet weight ratios of tissue around the wound among and within the three groups immediately after surgery and on PSD 7 (with F values respectively 0.70 and 0.09, t values from 0.17 to 0.52, P values above 0.05). (3) Immediately after surgery, the content of bacteria in wounds of rabbits in groups PD, BD, and SBD was respectively (603.0±146.0) ×10(4,) (573.0±63.0) ×10(4,) and (590.0±100.0)×10(4) colony-forming unit (CFU)/g, with no significant difference among them (F=0.13, P>0.05). On PSD 7, the content of bacteria in wounds of rabbits in groups PD, BD, and SBD were respectively (5.4±0.8) ×10(4,) (4.6±0.9) ×10(4,) and (3.5±0.9)×10(4) CFU/g. Among them, the content of bacteria in wounds of rabbits in group SBD was lower than that in groups PD and BD, respectively (with t values respectively 3.78 and 2.29, P<0.05 or P<0.01). The content of bacteria in wounds of rabbits in the three groups on PSD 7 was decreased compared with that immediately after surgery (with t values from 10.05 to 21.81, P values below 0.01). (4) There was no significant difference in content of TNF-α, IL-1β, and IL-6 in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values from 0.10 to 1.89, P values above 0.05). The content of TNF-α in wounds of rabbits in the three groups on PSD 7 was significantly higher than that immediately after surgery (with t values from 2.93 to 5.01, P<0.05 or P<0.01). (5) There was no significant difference in amount of fibroblasts in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values respectively 0.01 and 0.81, P values above 0.05). The amount of fibroblasts in wounds of rabbits in the three groups on PSD 7 was larger than that immediately after surgery (with t values from 4.78 to 11.58, P values below 0.01). (6) There was no significant difference in number of microvessels in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values respectively 2.42 and 2.49, P values above 0.05). The number of microvessels in wounds of rabbits in the three groups on PSD 7 was larger than that immediately after surgery (with t values from 7.17 to 11.14, P values below 0.01). Conclusions: SBD is better at inhibiting the growth of bacteria. PD, BD, and SBD have almost the same effects on reducing tissue edema and inflammatory reaction, and on promoting the accumulation of collagen fibers and tissue vascularization.

[Efficacy and safety of oseltamivir in children with suspected influenza: a multicenter randomized open-label trial]

Objective: To evaluate the efficacy and safety of oseltamivir in the treatment of suspected influenza in children. Method: A multicenter, randomized and open-label trial was conducted among 229 individuals with suspected influenza which were collected from the clinic of 5 hospitals in Guangdong province (Guangzhou Women and Children's Medical Center, Shenzhen Baoan District Maternity and Child Care Service Center, the Second Affiliated Hospital of Shantou University Medical College, Dongguan Maternity and Child Care Service Centre, Yuexiu District Children's Hospital of Guangzhou) from April to July 2015. They were randomized either to oseltamivir group (oseltamivir 30-75 mg, twice daily for 5 days) or control group who were given symptom relief medicines for 5 days. Result: No significant difference was found between two groups in influenza symptoms of the patients before the treatment(P>0.05). Altogether 229 individuals (114 in oseltamivir group, 115 in control group) were analyzed for efficacy, in which 73 individuals (42 oseltamivir, 31 control), 31.9%, were identified as influenza-infected through laboratory test. No significant difference was found between the two groups in the duration of fever although shortened. In the 229 individuals , the cumulative alleviation proportion between oseltamivir and control group was not significantly different (P>0.05): the median duration of illness was 69.9 hours (95% CI 65.3-91.5) in oseltamivir group and 75.4 hours (95%CI 63.9-91. 7) in control group; the median duration of fever was 40.4 hours (95%CI 31.5-53.4) in oseltamivir group and 44.0 hours (95%CI 33.2-50.0) in control group. In the 73 individuals, the cumulative alleviation proportion between oseltamivir and control group was significantly different (P<0.05). The median duration of illness was 61.2 hours (95%CI 48.0-121. 0) in oseltamivir group, being significantly shorter than that of 116.0 hours (95%CI 91.5-175.0) in control group. But it was not significantly different that the median duration of fever was 32.8 hours (95%CI 24.0-47.0 ) in oseltamivir group and 55.8 hours (95%CI 43.6-78.3 ) in control group (P>0.05). And the median duration of fever in 60 individuals (38 oseltamivir, 22 control) was significantly different between two groups(P<0.05), who had finished a course of taking oseltamivir in the 73 individuals, 34.8 hours (95%CI 24.0-48.5 ) in oseltamivir group being significantly shorter than that of 53.3 hours (95%CI 43.6-104.0 ) in control group. There was certain difference in side effects rate between the two groups (oseltamivir 10%, control 2%, P<0.05). The main side-effects were gastrointestinal symptoms (stomachache, diarrhea, poor appetite, vomiting). Conclusion: The duration of illness and fever in suspected influenza patients treated with oseltamivir was shorter than those in the patients treated with no oseltamivir, the difference was not statistically significant, when 31.9% was confirmed with positive result of virus test in suspected influenza in children. But in these patients with positive result of virus test, the duration of illness was significantly shortened with treatment with oseltamivir as compared with no treatment with oseltamivir, and it would be better if full oseltamivir course was completed for reducing the duration of fever. Oseltamivir treatment was safe with mild side effects.

[Progress in methodological characteristics of clinical practice guideline for osteoarthritis]

At present, several clinical practice guidelines for the treatment of osteoarthritis have been developed by institutes or societies. The ultimate purpose of developing clinical practice guidelines is to formulate the process in the treatment of osteoarthritis effectively. However, the methodologies used in developing clinical practice guidelines may place an influence on the transformation and application of that in treating osteoarthritis. The present study summarized the methodological features of individual clinical practice guideline and presented the tools for quality evaluation of clinical practice guideline. The limitations of current osteoarthritis guidelines of China are also indicated. The review article might help relevant institutions improve the quality in developing guide and clinical transformation.

Medium-term results of ceramic-on-polyethylene Zweymüller-Plus total hip arthroplasty

INTRODUCTION

The need for better durability and longevity in total hip arthroplasty for patients with various hip joint diseases remains a challenge. This study aimed to obtain medium-term results at a follow-up of >10 years for Zweymüller-Plus total hip arthroplasty with ceramic-on-polyethylene bearing.

METHODS

A retrospective study was conducted to review the results after a minimum of 12.4 years of 207 consecutive total hip arthroplasties in 185 patients in Peking University People's Hospital in China using the Zweymüller SL-Plus stem in combination with the Bicon-Plus threaded cup and ceramic-on-polyethylene bearing between October 1994 and April 2000.

RESULTS

During the study period, two patients (2 hips) died and 25 patients (28 hips) were lost to follow-up. Two hips were revised for aseptic loosening of the Bicon-Plus cup. The mean clinical and radiological follow-up was 14.1 years (range, 12.4-16.5 years) for the remaining 156 patients (175 hips). The mean (standard deviation) Harris Hip score for the 175 hips increased significantly from 39.3 (3.8) preoperatively to 94.1 (2.5) postoperatively at a mean follow-up of 14.1 years (P<0.05). Focal osteolysis was observed in seven (4.0%) of 175 stems and three (1.7%) of 175 cups. The Kaplan-Meier survival with revision for any reason as the end-point was 99.03% (95% confidence interval, 95%-100%).

CONCLUSIONS

The high survival rate of the cementless Zweymüller-Plus system with ceramic-on-polyethylene bearing at mid-term follow-up makes this total hip arthroplasty system reliable for patients with various hip joint diseases.

Aspergillus awamori-fermented mung bean seed coats enhance the antioxidant and immune responses of weaned pigs

The potential benefits of Aspergillus-fermented mung bean seed coats (FMSC) for weaned pigs remain unexplored. Both in vitro and in vivo experiments were employed to evaluate the potential of FMSC supplement on the growth, antioxidant and immune responses of weaned pigs. The total polyphenols and DPPH scavenging capability of ethanol extract of FMSC exhibited a greater (p < 0.01) increase than those of pre-fermentation. With the addition of the polyphenol of FMSC extract, an increase in phagocytosis by neutrophils and proliferation of peripheral blood mononuclear cells (PBMC) were found. However, these observations were significantly inhibited (p < 0.05) in those activated cells. Next, 96 weaned pigs were allotted with a randomized complete block design into four dietary treatments, including 0 (control), 600, 1200 or 1800 mg/kg FMSC in a corn-soya bean meal basal diet for a 35-day trial. The pigs were injected with swine enzootic pneumonia (SEP) vaccines at day 3 and day 21 respectively. The results showed that dietary treatment failed to affect growth performance or serum SEP titre. The diet supplemented with 600-1800 mg/kg FMSC decreased faecal lactoferrin on day 21 and increased plasma trolox equivalent antioxidant capacity (TEAC) and erythrocytes catalase activity, as well as decreased (p < 0.01) plasma malondialdehyde (MDA) concentration on day 35. Diet supplementation of 1800 mg/kg FMSC increased phagocytosis by neutrophils and PBMC proliferation induced by pokeweed mitogen (PWM). However, the polymorphonuclear leucocytes (PMN)-positive respiratory burst cells were decreased in the supplementation of 1200 or 1800 mg/kg FMSC respectively. In addition, the serum haptoglobin concentration was decreased in the supplementation with 1200 mg/kg FMSC. Taken together, FMSC enriches polyphenols with antioxidative and immune modulated properties. After feeding FMSC, an improvement in antioxidative capability and immunocompetence was found, implying that FMSC could provide as a feed additive at optimal level 1200 mg/kg for weaned pigs.

[The fees of patients with knee osteoarthritis]

Objective: To assess the cost of illness, the current medication treatment status and health service utilization of patients with knee osteoarthritis (OA). Methods: From January 2014 to May 2015, 250 patients in Arthritis Clinic and Research Center, Peking University People's Hospital were recruited and followed up for 12 months. There were four visits during the follow-up, i. e. baseline, 1, 6 and 12 month. Data on sociodemographic variables, direct cost of illness, medication utilization and health service utilization were obtained by the questionnaire for the analyses. Results: Two hundred and twelve participants had accomplished the 12-month follow-up. The direct cost of knee OA was (8 858±5 120) yuan per year , median number was 7 020 yuan. Medical-related cost was (7 184±4 890) yuan per year , median number was 5 420 yuan; comprising 81.1% of the direct cost, whereas the non-medical related cost was( 1 674±924) yuan(RMB) per year , median number (1 239) yuan, comprising 18.9% of the direct cost. The medication cost was (5 484±3 510) yuan , median number was 4 046 yuan, accounting for the largest proportion (76.3%) of the medical-related cost. As for the medication utilization, glucosamine was most commonly prescribed (64.8%), followed by the Chinese herbals (61.2%) and NSAIDs (48.8%). The average amount of the hospital-visit per year was (11.8±4.1). Most knee OA patients (68.8%) took the tertiary care hospital as their first choice when they consulted orthopedists or physicians for OA. Conclusion: The direct cost of OA patients is considerable. OA patients may take medicine blindly and not follow the current guidelines. The prevention and treatment of OA needs to be further standardized in the future.

[Effects on wound bed of deep burn following eschar excision with different wound management in rabbits]

OBJECTIVE

To compare the effects on wound bed of deep burn following eschar excision with different wound management in rabbits.

METHODS

Eighteen full-thickness burns models of Japanese white rabbits were established. They were randomly divided into 3 groups of traditional dressing, biological dressing and negative pressure wound therapy (NPWT) (n=6 each), according to the random number table. Eschar excision was performed three days later. The wound bed was observed and wound tissue was harvested for counting the quantity of bacteria, tissue dry wet ratio, measuring the level of tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β and IL-6, the amount of collagen fibers and the microvessel density instantly and again seven days later. Statistical analyses were performed.

RESULTS

The NPWT group was better than other groups by observing the wound bed. The quantity of bacteria of traditional dressing group, biological dressing group and NPWT group at the time point of seven days after escharectomy turned out to be (9.4±1.5)×10(4,) (8.1±2.7)×10(4,) (3.9±0.7)×10(4) cfu/g, the NPWT group was significantly lower than traditional dressing group and biological dressing group (both P<0.05), and all lower than that at the time point of the day when escharectomy was performed (576.9±169.5)×10(4,) (589.9±99.6)×10(4,) (583.0±160.4)×10(4) cfu/g ( all P<0.05). There were no statistically significant differences among three groups at two time points in tissue dry wet ratio (all P>0.05). The IL-6 of biological dressing group was higher than that of traditional dressing group at the time point of seven days after the eschar excision was performed[(94±10) vs (76±8) ng/L, P<0.05]. The amount of collagen fibers of three group at the time point of seven days after escharectomy turned out to be (60±9), (55±12), (77±17). The NPWT group was significantly higher than traditional dressing group and biological dressing group (P<0.05), and all higher than that at the time point of the day when escharectomy was performed[(39±6), (39±11), (38±6)](all P<0.05). The microvessel density of three groups at the time point of seven days after escharectomy turned out to be (42±6), (53±4), (82±10). The NPWT group was higher than that of the other two groups, and biological dressing group was higher than that of traditional dressing group (all P<0.05). The biological dressing group and NPWT group were both higher than that of the day when the eschar excision was performed (36±5) and (36±5) (P<0.05).

CONCLUSIONS

NPWT is the optimal selection for wound to inhibit the growth of bacteria, promote the accumulation of collagen and tissue vascularization. But these managements have similar effects on reducing tissue edema and inflammatory reaction.

[Evaluation of physical function for the end-stage osteoarthritis patient waiting for the total knee replacement]

OBJECTIVE

To collect comprehensive data of the physical function of the end-stage osteoarthritis (OA) patients, and compare it with patients with mild OA. To evaluate the correlations among pain, self-reported questionnaire, performance based physical function and actual daily life activity level.

METHODS

In this prospective study, the comprehensive physical function parameters of 87 end stage OA patients waiting for total knee replacement, and that of 60 patients with mild OA [Kellgren-Lawrence (K-L) grade 0-2] were collected. The comprehensive physical function parameters including: age, height, body weight, 30 s chair stand test (30-CST), 40 m fast-paced walk test (40-FPWT), 12 steps stair climb test (12-SCT), timed up & go test (TUG), 6 minutes walk test (6-MWT), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), knee society score (KSS), visual analogue scale (VAS) pain scale, and everyday steps counts for continuous 7 days. The data were analyzed with the soft ware SPSS 22.0. The descriptive report of all the parameters was made. Because the Kolmogorv-Smirnov test results for all the parameters were negative for normal distribution, nonparative Mann-Whitney test was used to analysis the differences between the two groups, as well as the Spearman test for the correlations.

RESULTS

All the parameters of the mild OA group were better than those of the end stage group, and the differences were significant (P<0.05). In the mild OA group, there were no correlations or weak correlations between all the physical function test and questionnaire, however, in the end stage group, the correlations were weak, moderate, or strong.

CONCLUSION

The usage of lots of different physical parameters from Chinese OA patients were reported in this study. The results showed that there are no good correlations among performance based physical function test, actual daily activity level, self reported questionnaires, and the pain scales. More comprehensive evaluation for the OA patients needs to be made, in order to make better decision for arthroplasty.

Rapid diagnosis of Naja atra snakebites

BACKGROUND

The clinical diagnosis of snakebites is critical and necessary in many parts of the world, especially in Southeastern Asia, where venomous snakebites are a burden on public health. It is difficult to define or recognize the species of venomous snake because of the overlapping clinical manifestations of envenomations. A quick and reliable method for identifying the snake species is necessary. We designed and tested a strip of lateral flow system for the diagnosis of cobra snake bites in Taiwan.

METHODS

We developed a kit based on an immunochromatographic method for rapid detection of cobra (Naja atra) venom in human serum. The test and control lines composed of 1 mg/ml polyclonal duck antivenom and 0.5 mg/ml goat anti-rabbit immunoglobulin antibody solutions, respectively, were coated on nitrocellulose strips. Colloidal gold was conjugated with rabbit polyclonal anti-cobra venom antibodies. From July 2007 to December 2012, we used the kit to test serum from snakebite patients and to examine the agreement between our rapid test and the currently used sandwich enzyme-linked immunosorbent assay (ELISA).

RESULTS

Our kit was able to detect cobra venom in serum samples in 20 minutes with a detection limit of 5 ng/ml. An absence of cross-reactivity with other non-cobra venoms from Taiwan was noted in vitro. A total of 88 snakebite patients (34 cobra and 54 other non-cobra) were tested. The sensitivity of the strips based on the ELISA results was 83.3% and the specificity was 100%. There was a strong agreement between the results of the ELISA and immunochromatographic strips (κ = 0.868).

DISCUSSION AND CONCLUSIONS

This data indicates that an immunochromatographic strip might be suitable for cobra venom detection and could be used as a quick diagnostic tool in cases of N. atra snakebite.

Identification of tristetraprolin as a factor that modulates the stability of the TAFI transcript through binding to the 3'-untranslated region

BACKGROUND

Thrombin-activatable fibrinolysis inhibitor (TAFI) is a basic carboxypeptidase zymogen encoded by the human gene CPB2. TAFI constitutes a molecular link between coagulation and fibrinolysis, and between coagulation and inflammation. The 3'-untranslated region (UTR) of the human CPB2 mRNA plays a key role in regulating CPB2 mRNA abundance, but the exact mechanisms that mediate this regulation are largely unexplored.

OBJECTIVES

To pinpoint cis-acting elements in the CPB2 3'-UTR that act as stability determinants and to identify protein factors binding to these sites.

METHODS

We constructed a series of plasmids encoding mRNAs containing rabbit β-globin sequences (as a reporter) fused to sequences of the CPB2 3'-UTR (encompassing 5' and internal deletions). These plasmids were transfected into HepG2 (human hepatoma) cells and the stability of the fusion transcripts measured. We performed a series of gel mobility shift analyses using RNA probes encompassing putative (in)stability elements.

RESULTS

We identified one element conferring stability and three elements conferring instability. Supershift assays identified the protein bound to the site between the second and third polyadenylation sites as tristetraprolin (TTP). Mutation of the TTP site abolished TTP binding in gel mobility shift assays and also stabilized β-globin/CPB2 fusion transcripts. TTP knockdown stabilized the fusion transcript containing the TTP site, but not a fusion transcript in which this site was mutated.

CONCLUSIONS

Our findings are indicative of a role for TTP in constitutive, and perhaps regulated, control of CPB2 mRNA stability and hence abundance.

Interleukin-10 promoter polymorphisms associated with susceptibility to lumbar disc degeneration in a Chinese cohort

We investigated a possible association between interleukin (IL)-10 single nucleotide polymorphisms (SNPs) and susceptibility to and severity of lumbar disc degeneration (LDD) in a Chinese cohort of 320 patients with LDD and 269 gender- and age-matched controls. The degree of disc degeneration was determined by magnetic resonance imaging using Schneiderman's classification. Genetic analysis of IL-10 promoter polymorphisms (at -1082 A/G, -819 T/C, and -592 A/C) was carried out by PCR-RFLP. A total of 134 herniated lumbar intervertebral discs were collected during surgery for IL-10 mRNA detection. For SNPs at -592, the A allele and AA genotype frequencies were significantly higher in LDD patients than in controls. Similarly, the AA genotype and A allele frequencies at -1082 were significantly higher in cases than in controls. Among the LDD subjects, carriers of AA at -592 and GG at -1082 had significantly lower mean IL-10 mRNA expression than the other two genotypes. The SNPs at each locus were not significantly associated with severity grade in the LDD patients. Logistic regression analyses showed that the AA at -1082, AA at -592, and IL-10 mRNA expression level were independent risk factors for LDD. We conclude that the IL-10 SNPs at -1082 A/G and -592 A/C as well as IL-10 mRNA in the herniated lumbar intervertebral discs are associated with susceptibility to LDD in this Chinese cohort, but not with disease severity.

Bias-dependent conductive characteristics of individual GeSi quantum dots studied by conductive atomic force microscopy

The bias-dependent electrical characteristics of individual self-assembled GeSi quantum dots (QDs) are investigated by conductive atomic force microscopy. The results reveal that the conductive characteristics of QDs are strongly influenced by the applied bias. At low (-0.5 to - 2.0 V) and high (-2.5 to - 4.0 V) biases, the current distributions of individual GeSi QDs exhibit ring-like and disc-like characteristics respectively. The current of the QD's central part increases more quickly than that of the other parts as the bias magnitude increases. Histograms of the magnitude of the current on a number of QDs exhibit the same single-peak feature at low biases, and double- or three-peak features at high biases, where additional peaks appear at large-current locations. On the other hand, histograms of the magnitude of the current on the wetting layers exhibit the same single-peak feature for all biases. This indicates the conductive mechanism is significantly different for QDs and wetting layers. While the small-current peak of QDs can be attributed to the Fowler-Nordheim tunneling model at low biases and the Schottky emission model at high biases respectively, the large-current peak(s) may be attributed to the discrete energy levels of QDs. The results suggest the conductive mechanisms of GeSi QDs can be regulated by the applied bias.

Changes in lymphocyte subsets in the peripheral blood of patients with active pulmonary tuberculosis

The aim of this study was to determine the percentage of lymphocyte subsets in peripheral blood in patients with active tuberculosis. A total of 21 patients with active tuberculosis and 15 healthy volunteers were included in the study. T-lymphocyte subsets, B-lymphocytes (CD19(+) cells), natural killer (NK) cells and cells positive for costimulatory molecules CD28 and CD152 were evaluated using flow cytometry. Patients with tuberculosis had a significantly decreased percentage of CD3(+) and CD3(+)CD4(+) cells, and a significantly decreased ratio of CD3(+)CD4(+) to CD3(+)CD8(+) cells compared with healthy controls. In contrast, the percentage of B-cells (CD19(+) cells), CD3(+)CD8(+) cells, CD28(+) cells, CD152(+) cells, and subpopulations of CD4(+)CD152(+), CD8(+)CD152(+) and CD8(+)CD28(+) T-cells were all significantly increased compared with healthy controls. There were no statistically significant differences in the percentages of NK cells or CD4(+)CD28(+) cells between patients and controls. These results indicate that patients with active tuberculosis have altered lymphocyte homeostasis.

Composition and strain measurements of Ge(Si)/Si(001) islands by HRTEM

The distributions of the composition and the strain in the Ge(Si)/Si(001) coherent islands grown by molecular-beam epitaxy are investigated by digital analysis of high resolution transmission electron microscopy (HRTEM) micrographs. Local composition and strain are obtained from the measurement of the lattice displacement based on the Poisson's formula and Vegard's law. The analysis suggests that the islands have high Ge content at the island's central region. The island is partially relaxed by the substrate deformation and strain concentrated around the edge of islands. The alloying of the islands was found due to the Si surface diffusion.

Comparative disposition of [14C]ertapenem, a novel carbapenem antibiotic, in rat, monkey and man

1. The disposition and metabolism of ertapenem, a carbapenem antibiotic, was examined in rat, monkey and man. Sprague-Dawley rats and Rhesus monkeys were given, by intravenous administration, radiolabelled doses of ertapenem (60 and 30 mg kg(-1), respectively), and healthy normal volunteers received a single fixed dose of 1000 mg. Urine and faeces were collected for determination of total radioactivity. 2. In healthy volunteers, [14C]ertapenem was eliminated by a combination of hydrolytic metabolism to a beta-lactam ring-opened derivative and renal excretion of unchanged drug. Approximately equal amounts were excreted as a beta-lactam ring-opened metabolite and unchanged drug (36.7 and 37.5% of dose, respectively). A secondary amide hydrolysis product accounted for about 1% of the dose in man. About 10% of the administered radioactivity was recovered in faeces, which suggested that a minor fraction underwent biliary and/or intestinal excretion. 3. In animals, a greater fraction of the dose was eliminated via metabolism; excretion of unchanged drug accounted for 17 and 5% of dose in rats and monkeys, respectively. In monkeys, the beta-lactam ring-opened and amide hydrolysis metabolites accounted for 74.8 and 7.59% of the dose, respectively, whereas in rats, these metabolites accounted for 31.9 and 20% of dose, respectively. 4. In vitro studies with fresh rat tissue homogenates indicated that lung and kidney were the primary organs involved in mediating formation of the beta-lactam ring-opened metabolite. The specific inhibitor of dehydropeptidase-I, cilastatin, inhibited the in vivo and in vitro metabolism of ertapenem in rats, which suggested strongly that the hydrolysis of ertapenem in lung and kidney was mediated by this enzyme.

Renal elimination of a novel and potent αvβ3integrin antagonist in animals

Compound A (3-{2-oxo-3-[3-(5,6,7,8-tetrahydro-[1,8]napthyridin-2-yl)propyl]-imidazolidin-1-yl}-3(S)-(6-methoxy-pyridin-3-yl)propionic acid), a hydrophilic zwitter-ion, is a potent and selective alphavbeta3 integrin antagonist currently under clinical development for the treatment of osteoporosis. The mechanism of renal excretion of compound A was investigated using a combination of in vivo and in vitro approaches. In rats, renal excretion of compound A involved tubular secretion; ratios between renal clearance, corrected for unbound fraction in plasma (CLr,u) and glomerular filtration rate (GFR) were greater than unity (2-5). The tubular secretion of compound A was saturable at high plasma levels (> 26 microM), and was inhibited significantly, although modestly (about twofold) by relatively high plasma concentrations of the organic anion PAH (160 microM) and the cation cimetidine (about 400 microM), but not by the P-gp inhibitor quinidine (about 50 microM). However, compound A (about 100 microM) had a minimal effect on CLr/GFRs for cimetidine and PAH. In rhesus monkeys, renal elimination of compound A also involved tubular secretion, with a CLr,u/GFR ratio of about 30. The renal secretion of compound A was not affected by either cimetidine (about 120 microM) or PAH (about 80 microM). Similarly, compound A (about 40 microM) had a minimal effect on the renal tubular secretion of both cimetidine and PAH. At the doses studied, neither rat nor monkey plasma protein binding of compound A, cimetidine or PAH was affected in the presence of each other. In vitro transport studies showed that compound A was not a substrate for P-gp in the Caco-2, human MDR1 and mouse mdr1a transfected LLC-PK1 cell lines. In an uptake study using rOAT1 and rOAT3 transfected HEK cell lines, compound A was shown to be a substrate for rat OAT3 (Km= 15 microM), but not rat OAT1. The results suggest that the tubular secretion of compound A is not mediated by P-gp, but rather is mediated, at least in part, via the organic anion transporter OAT3, the renal transporter shown to be capable of transporting both the organic anion PAH and the organic cation cimetidine. Although there is a possibility for pharmacokinetic interactions between compound A and substrates or inhibitors of OAT3, at the renal excretion level, the magnitude of interaction would likely be modest in humans at clinically relevant doses.

Effects of fibrates on human organic anion-transporting polypeptide 1B1-, multidrug resistance protein 2- and P-glycoprotein-mediated transport

The effects of different fibric acid derivatives (bezafibrate, clofibrate, clofibric acid, fenofibrate, fenofibric acid and gemfibrozil) on human organic anion transporting-polypeptide 1B1 (OATP2, OATP-C, SLC21A6), multidrug resistance protein 2 (MRP2/ABCC2) and MDR1-type P-glycoprotein (P-gp/ABCB1) were examined in vitro. Cyclosporin A (a known inhibitor of OATP1B1 and P-gp), MK-571 (a known inhibitor of MRP2) and cimetidine (an organic cation) were also tested. Bezafibrate, fenofibrate, fenofibric acid and gemfibrozil showed concentration-dependent inhibition of estradiol 17-beta-D-glucuronide uptake by OATP1B1-stably transfected HEK cells, whereas clofibrate and clofibric acid did not show any significant effects up to 100 microM. Inhibition kinetics of gemfibrozil, which exhibited the most significant inhibition on OATP1B1, was shown to be competitive with a Ki = 12.5 microM. None of the fibrates showed any significant inhibition of MRP2-mediated transport, which was evaluated by measuring the uptake of ethacrynic acid glutathione into MRP2-expressing Sf9 membrane vesicles. Only fenofibrate showed moderate P-gp inhibition as assessed by measuring cellular accumulation of vinblastine in a P-gp overexpressing cell-line. Cyclosporin A significantly inhibited OATP1B1 and P-gp, whereas only moderate inhibition was observed on MRP2. The rank order of inhibitory potency of MK-571 was determined as OATP1B1 (IC50: 0.3 microM) > MRP2 (4 microM) > P-gp (25 microM). Cimetidine did not show any effects on these transporters. In conclusion, neither MRP2- nor P-gp-mediated transport is inhibited significantly by the fibrates tested. Considering the plasma protein binding and IC50 values for OATP1B1, only gemfibrozil appeared to have a potential to cause drug-drug interactions by inhibiting OATP1B1 at clinically relevant concentrations.

Stereoselective hepatic disposition of a diastereomeric pair of αvβ3antagonists in rat

1. The study investigated mechanisms underlying the stereoselective hepatic disposition observed in rats of a zwitterionic diastereomeric pair ((3S)-3-[(3R or 3S)-2-oxo-3-[3-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl)propyl]pyrrolidin-1-yl]-3-quinolin-3-ylpropanoic acid) with different lipophilicities. 2. In a recirculating isolated rat liver system, the more hydrophilic diastereomer II possessed biliary clearance, CLb, and bile-to-liver concentration ratio higher (about 10-30-fold) than the lipophilic zwitterion I, whereas both I and II exhibited comparably high concentration ratios between liver and perfusate. Although MK-571, a known multidrug resistance protein (MRP) inhibitor, significantly inhibited the CLb of both compounds, it did not inhibit their canalicular transport, as evident by unchanged concentration ratios between bile and liver of either I or II. 3. Following an intravenous infusion of I or II to Sprague-Dawley rats, the biliary clearance calculated either based on plasma (CL(b,p)) or liver concentration (CL(b,l)), of II was much higher than that of I (about 5-50-fold). In rats lacking multidrug resistance protein 2 (Mrp2) (Eisai hyperbilirubinemic rat, EHBR), the biliary excretion rate and CL(b,p) of II were also higher than the corresponding values for I. However, both CL(b,p) or CL(b,l) of either I or II were not reduced in EHBR, as compared with control SD rats. 4. In the in vitro rat canalicular membrane vesicle study, I and II exhibited no differences in their inhibitory effect on the Mrp2 mediated ATP-dependent [3H]DNP-SG initial uptake (no inhibition at 10 microM and only about 40% inhibition at 100 microM). 5. Collectively, these results suggested that (1) the difference in the hepatic disposition between the two isomers was due primarily to the difference in their transport mechanism across the canalicular membrane and (2) Mrp2 did not play a major role in the observed differences in the biliary excretion of the diastereomers I and II in rats.

Diagnostic value and complications of fine needle aspiration for primary liver cancer and its influence on the treatment outcome-a study based on 3011 patients in China

AIM

To determine the diagnostic value and major complications of fine-needle aspiration (FNA) for primary liver cancer (PLC) and its influence on the treatment outcome and prognosis.

METHODS

Information was gathered retrospectively for 3011 patients who presented with suspected PLC. Of which 2528 cases underwent ultrasound-guided fine-needle aspiration (US-FNA) biopsy. Patients were followed up through repeated office visits and imaging studies with a median follow-up of 7 months (range, 1-29 months).

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of cytological diagnosis by FNA biopsy for detection of liver malignancy were 91.5%, 100.0%, 100.00%, 59.1% and 92.4% respectively. All patients with AFP> or = 400 microg/L were associated with malignancy. Of 1154 patients with AFP<400 microg/L who were finally proved PLC, 945 were detected by FNA alone. Major complications included bleeding in 11 cases (5 of them died later), occurred mainly in hepatocellular carcinoma with superficial location, large tumors and severe cirrhosis, and implantation metastases in 5 cases, which were recognized as a subcutaneous nodule at the previous biopsy site. Implantation metastases were treated with resection or radiotherapy.

CONCLUSION

FNA biopsy is valuable for the diagnosis of PLC. However, complications of post-biopsy hemorrhage should not be ignored, as such bleeding may be fatal. Implantation seems to have little effect on the prognosis.

Association of serum protein levels with egg productivity in Taiwan red-feathered country chickens

This study investigated the relationship between serum protein levels and egg productivity in Taiwan red-feathered country chickens (TRFCC). The total egg numbers of TRFCC (n=157) were recorded from 25 to 48 weeks of age. Serum samples were collected at 24 and 35 weeks of age, then classified by total egg number into four groups according to mean+/-1S.D. Serum X protein levels were evaluated by protein chip technology and with an insulin-like growth factor-I (IGF-I) immunoassay. Other serum proteins (apolipoprotein A-I, ovotransferrin and vitellogenin) were found at different levels between the most productive and the least productive groups of TRFCC, were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and were quantified by age. The results showed that levels of vitellogenin were positively correlated with total egg number at 24 and at 35 weeks old (p<0.01). Levels of apolipoprotein A-I and an IGF-1-related marker (termed X protein) in serum at 35 weeks old were correlated with total egg number (p<0.01). Serum ovotransferrin levels remained constant regardless of total egg number. To investigate the concentration differences among the four groups of TRFCC, serum protein levels of each group were analyzed by one-way ANOVA. The results showed that those protein levels, except for ovotransferrin, in the least productive group significantly differed from the other three groups (p<0.05). Although the correlation between those protein levels and the total egg number was not significant at the time of initial egg production, the selection strategy of those protein levels at later stages of egg production should provide a screening model to improve selection.

Mycoplasma hyorhinis in Taiwan: Diagnosis and isolation of swine pneumonia pathogen

This study attempted to determine whether one multiplex polymerase chain reaction (PCR) is an effective adjunct method for diagnosing Mycoplasma hyopneumoniae and Mycoplasma hyorhinis infection, and whether M. hyorhinis should be considered as an enzootic pneumonia or porcine respiratory disease complex pathogen in Taiwan. To our knowledge, this study is the first to isolate and identify M. hyorhinis as a porcine pathogen in Taiwan. A novel isolation method and a multiplex PCR test were applied to detect and isolate M. hyorhinis. The correlation of M. hyorhinis with swine pneumonia was also examined using a challenge test. Based on weight, 18 pigs were assigned to three groups and housed throughout the study in a specific-pathogen-free (SPF) facility and provided with aseptic feed and water. Groups 1 (n=6) and 2 (n=6) were challenged with 5mL M. hyorhinis culture via tracheal intubation on day 1. The M. hyorhinis strains ATIT-1, -3, and-7 were used to infect group 1 and the strain ATCC 27717 was used for group 2. Culture medium was replaced by phosphate-buffered saline in group 3 (n=6). All pigs were slaughtered on day 28, and their lungs were removed for examination of lesions. Of the six pigs in group 1 challenged with wild-type strains, two had typical mycoplasma pneumonia lesions. No gross lung lesions were observed in groups 2 and 3. Although further examination is necessary to confirm that wild-type strains can cause pneumonia, it appears that M. hyopneumoniae is no longer the only mycoplasma pathogen implicated in the diagnosis of swine enzootic pneumonia (SEP).

Industrial wideband noise reduction for hearing aids using a headset with adaptive-feedback active noise cancellation

High-intensity noises are a health hazard for industrial workers, and hearing protection is necessary to prevent hearing loss. Passive methods, such as ear muffs, are ineffective against low-frequency noise. Moreover, many hearing-impaired workers must wear hearing aids to enable communication at their workplace, and such aids can amplify ambient noise. To overcome this problem, the present study developed a headset equipped with a digital signal processing system to implement adaptive-feedback active noise cancellation (AFANC) to reduce low-frequency noise. The proposed AFANC headset was effective against wideband industrial noise, with a maximum noise spectrum power reduction of 30 dB. Furthermore, when used with a hearing aid, it improved the speech signal-to-noise ratio by up to 14 dB. These results suggest that a headset with AFANC would be useful for hearing protection in workplaces with high levels of low-frequency industrial noise, especially for hearing-impaired workers.