Dietary thyroid hormone improves growth and muscle protein accumulation of black-boned chickens

1. The objective of the study was to examine the effect of dietary thyroid hormone on performance and muscle protein accumulation of black-boned chickens. 2. A total of 720 1-d-old birds was housed in 24 pens and assigned to 4 diets containing triiodothyronine (T3) at 0, 0.1, 0.3 or 0.5 mg/kg. 3. The trial was split into starter (0 to 4 weeks) and grower (5 to 8 weeks) phases. At the beginning of the grower phase, each pen was split into two; one subgroup was fed basal diet (T3-) and the other continued with T3-added diet (T3+). 4. Dietary T3 at 0.1 mg/kg improved average daily body weight gain until week 6 but retarded it thereafter. However, T3 at 0.5 mg/kg depressed growth throughout the whole period. During weeks 7 to 8, T3 retarded growth, whereas growth recovered when T3 was withdrawn from the diet. 5. Birds fed the diet containing 0.1 mg/kg during weeks 0 to 4 and those receiving basal diet during weeks 5 to 8 showed the greatest thigh muscle growth, but this growth was depressed when they were fed the 0.5 mg/kg diet during weeks 0 to 8. 6. Serum T3 concentration was increased, while thyroxine (T4) concentration was decreased by dietary T3 treatment at 2 weeks old. At 4 weeks old, T3 and T4 concentrations decreased. At 6 and 8 weeks old, among T3-treated groups the serum T3 concentration of the T3- group was higher than that of the T3+ group. 7. In conclusion, dietary T3 improved weight gain and muscle growth of black-boned chickens before week 6, whereas supplementation depressed growth after 6 weeks. Optimum dietary T3 concentrations showed a carry-over effect on both body weight gain and thigh muscle growth.

A systemic provascular response in bone marrow to musculoskeletal trauma in mice

Post-natal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells migrate, differentiate and incorporate into the nacent endothelium and thereby contribute to physiological and pathological neurovascularisation, has stimulated much interest. Its contribution to neovascularisation of tumours, wound healing and revascularisation associated with ischaemia of skeletal and cardiac muscles is well established. We evaluated the responses of endothelial precursor cells in bone marrow to musculoskeletal trauma in mice.

Bone marrow from six C57 Black 6 mice subjected to a standardised, closed fracture of the femur, was analysed for the combined expression of cell-surface markers stem cell antigen 1 (sca-1+) and stem cell factor receptor, CD117 (c-kit+) in order to identify the endothelial precursor cell population. Immunomagnetically-enriched sca-1+ mononuclear cell (MNCsca-1+) populations were then cultured and examined for functional vascular endothelial differentiation. Bone marrow MNCsca-1+,c-kit+ counts increased almost twofold within 48 hours of the event, compared with baseline levels, before decreasing by 72 hours.

Sca-1+ mononuclear cell populations in culture from samples of bone marrow at 48 hours bound together Ulex Europus-1, and incorporated fluorescent 1,1′-dioctadecyl- 3,3,3,’3′-tetramethylindocarbocyanine perchlorate-labelled acetylated low-density lipoprotein intracellularily, both characteristics of mature endothelium.

Our findings suggest that a systemic provascular response of bone marrow is initiated by musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of neovascularisation and the healing of fractures.

First Report of Southern Blight Caused by Sclerotium rolfsii on Lily in China

Lily (Lilium spp.) is an economically important cut flower cultivated in China. The soilborne fungus, Sclerotium rolfsii, is a major pathogen on many plants. During July 2005, severe basal stem rot and bulb rot symptoms were observed on an oriental lily cultivar (Sorbonne) in some commercial fields in northern Kunming (China). Disease incidence ranged from 20 to 30% across fields. Leaves of infected plants were chlorotic initially. As the disease progressed, stems and bulbs rotted and plants wilted. In the presence of abundant moisture, a white mycelium occurred on infected tissues. White or light-to-dark brown sclerotia (1 to 3 mm in diameter) developed from mycelium. Fungal isolates from infected bulbs grown on potato dextrose agar (PDA) produced white mycelia and 1- to 2-mm diameter dark brown sclerotia. Sclerotia were nearly round with smooth surfaces and distributed over the entire colony. Isolates were identified as S. rolfsii on the basis of mycelial characteristics and color, size, and distribution of sclerotia. Pathogenicity was tested in the greenhouse on oriental lily cv. Sorbonne grown in pots (1 plant per pot, five replicates). Inoculum that consisted of 1 g per pot of wheat kernels infested with mycelium and sclerotia was placed at the base of each inoculated plant. Five noninoculated plants served as controls. The inoculation trial was repeated once. After inoculation, all plants were covered with a polyethylene bag for 72 h and kept at temperatures ranging between 25 and 27°C. Inoculated plants developed symptoms of leaf yellowing within 12 days, soon followed by the appearance of white mycelium and sclerotia, and then eventually wilted. Control plants remained symptomless. S. rolfsii was reisolated from inoculated plants. To our knowledge, this is the first report of southern blight caused by S. rolfsii on lily in China. Infection of lily bulbs by S. rolfsii may cause losses in production fields in China, and the presence of infected bulbs may also interfere with bulb shipment.

Mobilization of endothelial precursor cells: systemic vascular response to musculoskeletal trauma

Postnatal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells (EPC) migrate, differentiate, and incorporate into the nacent endothelium contributing to physiological and pathological neovascularization, has stimulated much interest. Its contribution to tumor nonvascularization, wound healing, and revascularization associated with skeletal and cardiac muscles ischaemia is established. We evaluated the mobilization of EPCs in response to musculoskeletal trauma. Blood from patients (n = 15) following AO type 42a1 closed diaphyseal tibial fractures was analyzed for CD34 and AC133 cell surface marker expression. Immunomagnetically enriched CD34+ mononuclear cell (MNC(CD34+)) populations were cultured and examined for phenotypic and functional vascular endothelial differentiation. Circulating MNC(CD34+) levels increased sevenfold by day 3 postinjury. Circulating MNC(AC133+) increased 2.5-fold. Enriched MNC(CD34+) populations from day 3 samples in culture exhibited cell cluster formation with sprouting spindles. These cells bound UEA-1 and incorporated fluorescent DiI-Ac-LDL intracellularily. Our findings suggest a systemic provascular response is initiated in response to musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of fracture healing.

Roles of mitogen-activated protein kinase pathways during Escherichia coli-induced apoptosis in U937 cells

Escherichia coli (E. coli) infections play an important and growing role in the clinic. In the present study, we investigated the involvement of members of the mitogen-activated protein kinase (MAPK) superfamily, including extracellular signal-regulated kinase (ERK), c-Jun NH(2)-terminal kinase (JNK) and p38 MAPK, and caspase-3 and 9 activity in E. coli-induced apoptosis in human U937 cells. We found that E. coli induces apoptosis in U937 cell lines in a dose- and time-dependent manner, p38 MAPK and JNK were activated after 10 min of infection with E. coli. In contrast, ERK1/2 was down-regulated in a time-dependent manner. The levels of total (phosphorylation state-independent) p38 MAPK, JNK and ERK1/2 did not change in E. coli-infected U937 cells at all times examined. Moreover, exposure of U937 cells to E. coli led to caspase-3 and 9 activity. For the evaluation of the role of MAPKs, PD98059, SB203580 and SP600125 were used as MAPKs inhibitors for ERK1/2, p38 MAPK and JNK. Inhibition of ERK1/2 with PD98059 caused further enhancement in apoptosis and caspase-3 and 9 activity, while a selective p38 MAPK inhibitor, SB203580 and JNK inhibitor, SP600125 significantly inhibited E. coli-induced apoptosis and caspase-3 and 9 activity in U937 cells. The results were further confirmed by the observation that the caspase inhibitors Z-DEVD-FMK and Z-LEHD-FMK blocked E. coli-induced U937 apoptosis. Taken together, we have shown that E. coli increase p38 MAPK and JNK and decrease ERK1/2 phosphorylation and increase caspase-3 and 9 activity in U937 cells.

Laparoscopic surgery protects against the oncologic adverse effects of open surgery by attenuating endothelial progenitor cell mobilization

BACKGROUND

Endothelial progenitor cells (EPCs) derived from bone marrow incorporate into foci of neovascularization to propagate tumor growth. These cells are mobilized in response to surgical injury. Laparoscopic surgery may protect against the oncologic adverse effects of open surgical tumor excision, and this may be related to attenuated mobilization of EPCs.

METHODS

For this study, 132 C57BL/6 mice were randomized to standardized laparotomy, laparoscopy, or control groups. The animals were killed at 6, 24, 48, and 72 h. Femur bone marrow and peripheral blood were harvested. Bone marrow EPCs were detected by flow cytometric dual staining for the stem cell antigen-1/cKit phenotype. Circulating EPCs were characterized in blood by vascular endothelial growth factor receptor 2 positive/macrophage activating complement-1 negative staining. Separately, 12 C57/bl6 mice bearing 3LL Lewis lung tumors 12 days after laparotomy or laparoscopy had their tumors excised and examined for endothelial cell expression (marker P1H12).

RESULTS

Laparoscopy decreased circulating EPCs and bone-marrow EPC levels, as compared with laparotomy, at all time points. Bone marrow EPC levels were 2.95% +/- 0.32% after laparotomy, as compared with 0.65 +/- 0.21 in the laparoscopy group (p < 0.05). The circulating EPC level in the laparotomy group was 35.2% +/- 6% of cells, as compared with 3.1% +/- 0.2% in the laparoscopy group (p < 0.05). In homogenized tumors, the percentage of P1H12 expression among laparoscopy-treated animals was 22.1% +/- 4.2%, as compared with 39% +/- 8% in the laparotomy group (p < 0.05).

CONCLUSION

Laparoscopy decreased EPC levels in both bone marrow and circulation, resulting in decreased tumor endothelial cell burden. This may represent a novel mechanism by which laparoscopy protects against the oncologic adverse effects of open surgical tumor excision.

Can surgery for cancer accelerate the progression of secondary tumors within residual minimal disease at both local and systemic levels?

BACKGROUND

Surgical removal remains the principal treatment modality in the management of lung cancer. Our aim is to characterize the effects of tumor removal on subsequent tumor recurrence at both local and systemic levels.

METHODS

C57/BL6 mice [10/group] underwent a mammary fat pad inoculation of 3LL cells [5 x 10(5)/animal] and were divided into two groups. Group 1 served as control while mice in group 2 were further subdivided into groups 2A and 2B. After 2 weeks, all mice in 2A were killed, and primary tumors and lungs were excised. At 2 weeks, primary tumors were excised completely for all mice in group 2B. These mice were then recovered and recurrent tumor growth evaluated for a further 2 weeks. Four weeks from the onset of the study, all remaining primary tumors and lungs were excised from groups 1 and 2.

RESULTS

After 4 weeks undisturbed growth, primary tumors in group 1 reached a mean size of 2.85 +/- 0.33 cm. After 2 weeks growth, primary tumors in groups 2A and 2B were comparable at 1.36 +/- 0.44 m and 1.53 +/- 0.29 cm, respectively. Two weeks after primary tumor excision, recurrent tumors in group 2B had reached a mean size of 2.65 +/- 0.74 cm. Moreover, for several animals, recurrent tumors rapidly reached similar volumes to that of primary tumors in group 1. Primary tumors were typically encapsulated and nonadherent. In contrast, recurrent tumors were locally invasive and adherent to chest wall and wound. Interestingly, pulmonary metastatic burden was increased in group 2B relative to group 1. Histologic examination revealed increased mitosis in recurrent tumors when compared with primary tumors.

CONCLUSIONS

Tumor removal is followed by accelerated growth of locally recurrent tumors and metastases. Moreover, recurrent tumors are more locally invasive than primary tumors. These findings strongly indicate that resection may be followed by tumor progression in residual disease.

Exploitation of the Toll-like receptor system in cancer: a doubled-edged sword?

The toll-like receptor (TLR) system constitutes a pylogenetically ancient, evolutionary conserved, archetypal pattern recognition system, which underpins pathogen recognition by and activation of the immune system. Toll-like receptor agonists have long been used as immunoadjuvants in anti cancer immunotherapy. However, TLRs are increasingly implicated in human disease pathogenesis and an expanding body of both clinical and experimental evidence suggests that the neoplastic process may subvert TLR signalling pathways to advance cancer progression. Recent discoveries in the TLR system open a multitude of potential therapeutic avenues. Extrapolation of such TLR system manipulations to a clinical oncological setting demands care to prevent potentially deleterious activation of TLR-mediated survival pathways. Thus, the TLR system is a double-edge sword, which needs to be carefully wielded in the setting of neoplastic disease.

Preoperative Evaluation of Resectability of Klatskin Tumor with 16-MDCT Angiography and Cholangiography

OBJECTIVE

The objective of our study was to evaluate prospectively the preoperative use of 16-MDCT angiography and cholangiography in determining the resectability of Klatskin tumors.

CONCLUSION

Preoperative MDCT angiography and cholangiography gave a good assessment of the degree of vascular and biliary involvement of the Klatskin tumor.

Ketamine affects memory consolidation: Differential effects in T-maze and passive avoidance paradigms in mice

The effects of ketamine, an N-methyl-D-aspartate (NMDA) antagonist, on memory in animals have been limited to the sub-anesthetic dose given prior to training in previous studies. We evaluated the effects of post-training anesthetic doses of ketamine to selectively manipulate memory consolidation, and the effect of pre-retention sub-anesthetic doses of ketamine on memory retrieval in passive avoidance and T-maze tasks in mice. Repeated post-training anesthetic doses of ketamine impaired the consolidation of memory in the T-maze but not in passive avoidance paradigms. This impairment was not permanent but diminished 1-2 days after ketamine withdrawal. Sub-anesthetic post-training doses of ketamine (5 mg/kg) had no effect on memory consolidation, and larger doses (10, 20 and 50 mg/kg) did not influence the retrieval of memory in the T-maze. The data suggest that repeated anesthetic doses of ketamine block NMDA receptors and affect memory consolidation. Moreover, NMDA mechanisms antagonized by ketamine appear to be selectively involved in spatial (T-maze) memory mechanisms but may not be necessary for non-spatial (passive avoidance) memory consolidation.

Cancer surgery: risks and opportunities

In the recent past, several papers have pointed to the possibility that tumour removal generates a permissive environment in which tumour growth is potentiated. This phenomenon has been coined "perioperative tumour growth" and whilst it represents a departure in terms of our attitude to the surgical process, this concept was first hinted at by Paget(1) himself. Despite this, the time interval immediately before and after cancer surgery (i.e. the perioperative period) remains an underutilised interval during which chemotherapeutic regimens are rarely implemented. Herein, we present a summarised review of the literature that supports the concept that tumour removal may potentiate the growth of residual neoplastic disease. We also outline current knowledge regarding underlying mechanisms and in this manner highlight potential therapeutic entry points. Finally, we emphasise the urgent need for trials of agents that could protect patients against the harmful host-tumour interactions that may occur during the perioperative period.

Surgically induced accelerated local and distant tumor growth is significantly attenuated by selective COX-2 inhibition

BACKGROUND

Even after apparently curative resection, lung cancer recurrence continues to lead to high mortality levels. The aim of this study was to assess the effects of cyclooxygenase-2 (COX-2) inhibitor on local and systemic recurrent tumor growth.

METHODS

C57BL/6 mice underwent mammary fat pad inoculation with 3LL cells. After two weeks growth, flank tumors were resected completely and followed for recurrent tumor growth. Postresection mice were randomized to receive placebo alone (group 1) or the selective COX-2 inhibitor, rofecoxib (group 2), daily for two weeks by tube feeding. Recurrent tumor growth kinetics were compared for both groups. Two weeks following primary tumor excision animals were sacrificed, after which lungs were resected and pulmonary metastatic burden was assessed using the lung-body weight ratio. Apoptotic and mitotic indices were established for recurrent tumors and lungs, using hematoxylin and eosin histology.

RESULTS

Two weeks postexcision of the primary tumor, recurrent tumors in the placebo group were significantly greater than the treatment group (p = 0.002). While primary tumors were typically encapsulated and not adherent, recurrent tumors in the placebo group were invasive, adherent to the chest wall and the overlying wound. In contrast, recurrent tumors in the treatment group were nonadherent to the chest wall. Moreover, postoperative pulmonary metastatic burden was significantly reduced in treated animals. Histologic examination revealed increased apoptosis as well as an increase in the apoptosis-mitosis ratio in treated animals.

CONCLUSIONS

Primary tumor excision was associated with accelerated local and systemic tumor recurrence. However, these effects were significantly attenuated using selective COX-2 inhibition. The COX-2-inhibition was associated with increased levels of apoptosis. These findings endorse a role for COX-2 inhibition in the secondary prevention of lung cancer recurrence at both local and systemic levels.

Activated protein C attenuates acute ischaemia reperfusion injury in skeletal muscle

Activated protein C (APC) is an endogenous anti-coagulant with anti-inflammatory properties. The purpose of the present study was to evaluate the effects of activated protein C in the setting of skeletal muscle ischaemia reperfusion injury (IRI). IRI was induced in rats by applying rubber bands above the levels of the greater trochanters bilaterally for a period of 2h followed by 12h reperfusion. Treatment groups received either equal volumes of normal saline or activated protein C prior to tourniquet release. Following 12h reperfusion, muscle function was assessed electrophysiologically by electrical field stimulation. The animals were then sacrificed and skeletal muscle harvested for evaluation. Activated protein C significantly attenuated skeletal muscle reperfusion injury as shown by reduced myeloperoxidase content, wet to dry ratio and electrical properties of skeletal muscle. Further in vitro work was carried out on neutrophils isolated from healthy volunteers to determine the direct effect of APC on neutrophil function. The effects of APC on TNF-alpha stimulated neutrophils were examined by measuring CD18 expression as well as reactive oxygen species generation. The in vitro work demonstrated a reduction in CD18 expression and reactive oxygen species generation. We conclude that activated protein C may have a protective role in the setting of skeletal muscle ischaemia reperfusion injury and that this is in part mediated by a direct inhibitory effect on neutrophil activation.

Hepatic potential of bone marrow stromal cells: development of in vitro co-culture and intra-portal transplantation models

Bone marrow comprises heterogeneous cell populations and is thought to contain certain progenitors with the ability to differentiate into multiple mesenchymal cell lineages. To identify any differentiation plasticity of adult bone marrow stromal cells (BMSCs) into hepatocyte-like phenotypes, we developed a co-culture model with damaged liver tissue and an animal model of engraftment in cirrhotic liver via intra-portal transplantation. After 10 days of co-culture with injured liver tissues, BMSC expressed specific markers for hepatocytes by RT-PCR and Western blot. The two animal models for liver injury employed used carbon tetrachloride (CCl4) induction or bile duct ligation. For tracing BMSC resident in the liver after intra-portal transplantation, green fluorescent protein (GFP)-positive BMSCs or in situ hybridization of Y-chromosome Sry gene in male BMSC were used in a cross-sex transplantation model. Expression of hepatocyte-specific markers in recipients' liver tissues was determined by fluorescence immunohistochemistry. Our findings demonstrated that about 16% parenchyma cells were GFP-positive cells derived from infused BMSCs, and expression of albumin was detected in these cells in engrafted liver tissues. In conclusion, BMSCs exhibited hepatocyte-like phenotypes after co-cultivation with liver tissue and transplanted into the injured liver. The presented evidence indicated the trans differentiation potential of BMSC developing to the hepatocytes.

The effect of lidocaine on in vitro neutrophil and endothelial adhesion molecule expression induced by plasma obtained during tourniquet-induced ischaemia and reperfusion

BACKGROUND

Changes in neutrophil and endothelial adhesion molecule expression occur during perioperative ischaemia and reperfusion (I/R) injury. We investigated the effects of lidocaine on neutrophil-independent changes in neutrophil and endothelial adhesion molecule expression associated with tourniquet-induced I/R.

METHODS

Plasma was obtained from venous blood samples (tourniquet arm) taken before (baseline), during, 15 min, 2 and 24 h following tourniquet release in seven patients undergoing elective upper limb surgery with tourniquet application. Isolated neutrophils from healthy volunteers (n = 7) were pretreated in the presence or absence of lidocaine (0.005, 0.05 and 0.5 mg mL(-1) for 1 h, and then incubated with I/R plasma for 2 h. Human umbilical vein endothelial cells (HUVECs) were pretreated in the presence or absence of lidocaine (0.005, 0.05 and 0.5 mg mL(-1)) for 1 h, and then incubated with the plasma for 4 h. Adhesion molecule expression was estimated using flow cytometry. Data were analysed using ANOVA and post hoc Student-Newman-Keuls tests.

RESULTS

I/R plasma (withdrawn 15 min following tourniquet release) increased isolated neutrophil CD11b (P = 0.03), CD18 (P = 0.01) and endothelial intercellular adhesion molecule-1 (ICAM-1) (P = 0.008) expression compared to baseline. CD11b, CD18 and ICAM-1 expression on lidocaine (0.005 mg mL(-1)) treated neutrophils was similar to control. CD11b (P < 0.001), CD18 (P = 0.03) and ICAM-1 (P = 0.002) expression on lidocaine (0.05 mg mL(-1)) treated neutrophils and HUVECs was less than that on controls.

CONCLUSION

Increased in vitro neutrophil and endothelial cell adhesion molecule expression on exposure to plasma obtained during the early reperfusion phase is diminished by lidocaine at greater than clinically relevant plasma concentrations.

The effect of lidocaine on neutrophil CD11b/CD18 and endothelial ICAM-1 expression and IL-1beta concentrations induced by hypoxia-reoxygenation

BACKGROUND

Lidocaine has actions potentially of benefit during ischaemia-reperfusion. Neutrophils and endothelial cells have an important role in ischaemia-reperfusion injury.

METHODS

Isolated human neutrophil CD11b and CD18, and human umbilical vein endothelial cell (HUVEC) ICAM-1 expression and supernatant IL-1beta concentrations in response to hypoxia-reoxygenation were studied in the presence or absence of different concentrations of lidocaine (0.005, 0.05 and 0.5 mg mL(-1)). Adhesion molecule expression was quantified by flow cytometry and IL- 1beta concentrations by ELISA. Differences were assessed with analysis of variance and Student-Newman-Keuls as appropriate. Data are presented as mean+/-SD.

RESULTS

Exposure to hypoxia-reoxygenation increased neutrophil CD11b (94.33+/-40.65 vs. 34.32+/-6.83 mean channel fluorescence (MCF), P = 0.02), CD18 (109.84+/-35.44 vs. 59.05+/-6.71 MCF, P = 0.03) and endothelial ICAM-1 (146.62+/-16.78 vs. 47.29+/-9.85 MCF, P < 0.001) expression compared to normoxia. Neutrophil CD18 expression on exposure to hypoxia-reoxygenation was less in lidocaine (0.005 mg mL(-1)) treated cells compared to control (71.07+/-10.14 vs. 109.84+/-35.44 MCF, P = 0.03). Endothelial ICAM-1 expression on exposure to hypoxia-reoxygenation was less in lidocaine (0.005 mg mL(-1)) treated cells compared to control (133.25+/-16.05 vs. 146.62+/-16.78 MCF, P = 0.03). Hypoxia-reoxygenation increased HUVEC supernatant IL-1beta concentrations compared to normoxia (3.41+/-0.36 vs. 2.65+/-0.21 pg mL(-1), P = 0.02). Endothelial supernatant IL-1beta concentrations in lidocaine-treated HUVECs were similar to controls.

CONCLUSIONS

Lidocaine at clinically relevant concentrations decreased neutrophil CD18 and endothelial ICAM-1 expression but not endothelial IL-1beta concentrations.

Three-dimensional ultrasound diagnosis of Larsen syndrome with further characterization of neurological sequelae

Larsen syndrome consists of skeletal dysplasia with multiple joint dislocations and a characteristic facies. The basis of this abnormality is a generalized mesenchymal disorder involving connective tissues. We describe our findings in a woman who was referred at 28 weeks' gestation due to multiple fetal anomalies suspected initially at an 18-week ultrasound examination. On three-dimensional (3D) ultrasound we found the fetus had bilateral genu recurvatum. Further 3D examination at 36 weeks confirmed the lower limb anomaly and revealed facial anomalies that led to the diagnosis of Larsen syndrome. An elective Cesarean section was performed at 38 weeks' gestation to minimize neurological sequelae. Magnetic resonance imaging was performed postnatally and showed pachygyria, colpocephaly and agenesis of the corpus callosum. In this case, 3D ultrasound facilitated the prenatal diagnosis of Larsen syndrome. A careful prenatal investigation for other associated anomalies such as those of the cardiovascular or neurological systems is warranted with this diagnosis. These associated lesions are likely to have a greater impact on prognosis than the classic symptoms of Larsen syndrome and a collaborative approach is necessary to optimize delivery and postnatal management of an affected fetus.

Surgical injury induces the mobilization of endothelial progenitor cells

BACKGROUND

Endothelial progenitor cells (EPCs) are derived from the bone marrow and incorporate into the foci of tumor neovascularization to increase tumor growth. We hypothesized that surgery induces the mobilization of EPCs.

METHODS

C57BL/6 mice were assigned randomly to standardized laparotomy or anesthesia-only treatment groups (n=102 mice). Animals were killed at 6, 24, 48, and 72 hours. Bone marrow EPCs were detected by blood flow cytometric dual staining for stem cell antigen-1/cKit. Circulating EPCs were characterized in blood by vascular endothelial growth factor receptor 2(+)/macrophage activating complement-1(-) staining. EPCs were detected in splenic homogenates by dual staining for lectin and acetylated low-density lipoprotein uptake. Plasma vascular endothelial growth factor was determined by enzyme-linked immunosorbent assay.

RESULTS

Surgery induced increases in bone marrow and splenic EPC levels (0.2% +/- 0.01% vs 2.9% +/- 0.3%) at 24 hours and in circulating EPC levels (2.5% +/- 0.01% vs 35.2% +/- 6%) at 48 hours compared with control subjects (P <.001). Surgical injury also caused an increase in vascular endothelial growth factor release (81 +/- 8 vs 14 +/- 2 pg; P>.02).

CONCLUSIONS

EPCs were mobilized by surgical injury, which may have implications for residual and metastatic tumor growth during the perioperative period.

Dual tachykinin NK1/NK2 antagonist DNK333 inhibits neurokinin A-induced bronchoconstriction in asthma patients

Inhalation of neurokinin A (NKA) causes bronchoconstriction in patients with asthma. In vitro both tachykinin NK1 and NK2 receptors can mediate airway contraction. In this study the authors examined the effects of a single dose of the dual tachykinin NK1/NK2 receptor antagonist, DNK333, on NKA-induced bronchoconstriction in asthma. A total of 19 male adults with mild asthma completed a randomised, double-blind, placebo-controlled crossover trial. Increasing concentrations of NKA (3.3x10(-9) to 1.0x10(-6) mol x mLP(-1)) were inhaled at 1 and 10 h intervals after a single oral dosing with either DNK333 (100 mg) or a placebo. It was observed that DNK333 did not affect baseline lung function but did protect against NKA-induced bronchoconstriction in those patients. The mean log10 provocative concentration causing a 20% fall in forced expiratory volume in one second for NKA was -5.6 log10 mol x mL(-1) at 1 h after DNK333 treatment and -6.8 log10 mol x mL(-1) after placebo. This was equivalent to a difference of 4.08 doubling doses, which decreased to a difference of 0.90 doubling doses 10 h after treatment. The results shown in this report indicate that DNK333 blocks neurokinin A-induced bronchoconstriction in patients with asthma.

Decoy receptor 3 (DcR3) induces osteoclast formation from monocyte/macrophage lineage precursor cells

Recent evidence indicates that the decoy receptor 3 (DcR3) of the TNF receptor superfamily, which initially though prevents cytokine responses of FasL, LIGHT and TL1A by binding and neutralization, can modulate monocyte function through reverse signaling. We show in this work that DcR3 can induce osteoclast formation from human monocytes, murine RAW264.7 macrophages, and bone marrow cells. DcR3-differentiated cells exhibit characteristics unique for osteoclasts, including polynuclear giant morphology, bone resorption, TRAP, CD51/61, and MMP-9 expression. Consistent with the abrogation of osteoclastogenic effect of DcR3 by TNFR-Fc, DcR3 treatment can induce osteoclastogenic cytokine TNF-alpha release through ERK and p38 MAPK signaling pathways. We conclude that DcR3 via coupling reverse signaling of ERK and p38 MAPK and stimulating TNF-alpha synthesis is a critical regulator of osteoclast formation. This action of DcR3 might play an important role in significant osteoclastic activity in osteolytic bone metastases.

Excisional surgery for cancer cure: therapy at a cost

Excisional surgery is one of the primary treatment modalities for cancer. Minimal residual disease (MRD) is the occult neoplastic disease that remains in situ after curative surgery. There is increasing evidence that tumour removal alters the growth of MRD, leading to perioperative tumour growth. Because neoplasia is a systemic disease, this phenomenon may be relevant to all patients undergoing surgery for cancer. In this review we discuss the published work that addresses the effects of tumour removal on subsequent tumour growth and the mechanisms by which tumour excision may alter residual tumour growth. In addition, we describe therapeutic approaches that may protect patients against any oncologically adverse effects of tumour removal. On the basis of the evidence presented, we propose a novel therapeutic paradigm; that the postoperative period represents a window of opportunity during which the patient may be further protected against the oncological effects of tumour removal.

Peritoneal serous papillary carcinoma: a reappraisal of CT imaging features and literature review

We evaluated the imaging features of primary serous peritoneal carcinoma (PSPC) on computed tomography (CT) and reviewed the literature. Preoperative CT images of 11 women with PSPC were retrospectively reviewed. The clinical presentations and serum levels of CA-125 were recorded. Special attention was paid to the operative and histopathologic findings of the ovaries. Imaging features were correlated with those in the literature. An elevation of serum CA-125 was found in 91% of cases. The CT findings included ascites (82%), peritoneal nodules or masses (73%), and omental nodules or omental caking (64%). Absence of an overt ovarian mass was observed in 64% of cases. The clinical manifestations and imaging features in our patients were consistent with those in the literature. Eighty-five percent of the ovaries in our study were superficially involved by PSPC in histopathologic examination. In none of our cases could the ovarian size be clearly assessed in the CT images. In conclusion, the presence of diffuse peritoneal disease and the absence of an ovarian mass on CT and an elevation of serum CA-125 level is suggestive of PSPC. However, in our experience, the evaluation of ovarian morphology and size by CT alone may not be as reliable.

Adenovirus-mediated interleukin-2 gene therapy of nociception

The effect of adenovirus-mediated interleukin-2 (IL-2) gene on rat basal nociceptive response and chronic neuropathic pain was explored. The paw withdrawal latency induced by radiant heat was used to evaluate the antinociceptive effect of adenovirus type 5 (Ad5) and Ad5-IL-2. The results showed that intrathecal delivery of Ad5-IL-2 exhibited obvious antinociceptive effects on basal nociceptive response and chronic neuropathic pain, which were maintained for 3 and 4 weeks, respectively. This suggested that the antinociceptive effect of Ad5-IL-2 on chronic neuropathic pain was greater than its effect on basal nociceptive response. Human IL-2 mRNA was detected by in situ hybridization in the spinal pia mater and parenchyma of the lumbar, sacral, thoracic and cervical regions, and gray matter had higher level of IL-2 expression than white matter. These data demonstrated that the IL-2 gene was transfected into spinal cord regions relevant to pain modulation. The expressed IL-2 protein profile in spinal cord detected by enzyme-linked immunosorbent assay coincided almost exactly with its antinociceptive effect. This supported the hypothesis that the therapeutic effect of IL-2 gene was related to IL-2 protein expression. The study indicates that intrathecal delivery of adenovirus-mediated IL-2 gene has a relatively long antinociceptive effect.

Attenuation of pancreatitis-induced pulmonary injury by aerosolized hypertonic saline

BACKGROUND

The immunomodulatory effects of hypertonic saline (HTS) provide potential strategies to attenuate inappropriate inflammatory reactions. This study tested the hypothesis that administration of intratracheal aerosolized HTS modulates the development of lung injury in pancreatitis.

METHODS

Pancreatitis was induced in 24 male Sprague-Dawley rats by intraperitoneal injection of 20% L-arginine (500 mg/100 g body weight). At 24 and 48 h, intratracheal aerosolized HTS (7.5% NaCl, 0.5 mL) was administered to 8 rats, while a further 8 received 0.5 mL of aerosolized normal saline (NS). At 72 hours, pulmonary neutrophil infiltration (myeloperoxidase activity) and endothelial permeability (bronchoalveolar lavage and wet:dry weight ratios) were assessed. In addition, histological assessment of representative lung tissue was performed by a blinded assessor. In a separate experiment, polymorphonucleocytes (PMN) were isolated from human donors, and exposed to increments of HTS. Neutrophil transmigration across an endothelial cell layer, VEGF release, and apoptosis at 1, 6, 12, 18, and 24 h were assessed.

RESULTS

Histopathological lung injury scores were significantly reduced in the HTS group (4.78 +/- 1.43 vs. 8.64 +/- 0.86); p < 0.001). Pulmonary neutrophil sequestration (1.40 +/- 0.2) and increased endothelial permeability (6.77 +/- 1.14) were evident in the animals resuscitated with normal saline when compared with HTS (0.70 +/- 0.1 and 3.57 +/- 1.32), respectively; p < 0.04). HTS significantly reduced PMN transmigration (by 97.1, p = 0.002, and induced PMN apoptosis (p < 0.03). HTS did not impact significantly upon neutrophil VEGF release (p > 0.05).

CONCLUSIONS

Intratracheal aerosolized HTS attenuates the neutrophil-mediated pulmonary insult subsequent to pancreatitis. This may represent a novel therapeutic strategy.

Taurine and vitamin C modify monocyte and endothelial dysfunction in young smokers

BACKGROUND

Endothelial dysfunction initiated by monocyte-endothelial interactions has previously been observed in many vasculopathies, including chronic cigarette smoking. Taurine, a semiessential amino acid, and vitamin C, a naturally occurring antioxidant, have previously been shown to have endothelial protective effects when exposed to proinflammatory insults. Therefore, we hypothesized that taurine and vitamin C would restore endothelial function in young smokers by modifying monocyte-endothelial interactions.

METHODS AND RESULTS

Endothelial-dependent vasodilatation was assessed in vivo using duplex ultrasonography, and monocyte-endothelial interactions were assessed in vitro using endothelial cell culture (human umbilical vein endothelial cells [HUVECs]) with monocyte-conditioned medium (MCM). Endothelial-dependent vasodilatation was significantly impaired in young smokers compared with nonsmokers. Pretreatment of young smokers for 5 days with 2 g/d vitamin C and, more significantly, with 1.5 g/d taurine attenuated this response. MCM taken from smokers impaired the release of nitric oxide and increased the levels of endothelin-1 release from HUVECs. When HUVECs were cultured with MCM from smokers who had been treated with taurine, the levels of nitric oxide and endothelin-1 returned toward control levels. This was attributed to an upregulation in endothelial nitric oxide synthase expression.

CONCLUSIONS

These observations suggest that taurine supplementation has a beneficial impact on macrovascular endothelial function, and an investigation of its effect on altered endothelial function in dyslipidemic states is warranted.

Prevalence and clinical implications of hepatitis B virus genotypes in southern Taiwan

BACKGROUND

Hepatitis B virus (HBV) infection is a major health problem. HBV genotypes may be associated with progression of liver disease. The distribution and clinical implications of HBV genotypes in southern Taiwan are evaluated.

METHODS

We used a polymerase chain reaction-restriction fragment length polymorphism genotyping method to determine HBV genotypes.

RESULTS

The genotype distribution for 265 patients with chronic HBV infection was as follows: A, 3 (1%); B, 158 (60%); C, 90 (34%); D, 7 (2.5%); E, 0: F, 0; and unclassified, 7 (2.5%). Compared with genotype B patients, genotype C patients had a higher hepatitis B e antigen positive rate and higher fibrosis score. There was no significant difference in the mean age between genotype B and genotype C patients with hepatocellular carcinoma (HCC). However, when patients were stratified by age, the prevalence of genotype C was significantly higher in young HCC patients (<50 years of age) than in age-matched asymptomatic carriers (40% versus 10%, P < 0.001). Using multivariate analysis, the significant risk factors for advanced liver disease (cirrhosis or HCC) for patients with chronic HBV infection were old age, male gender and genotype C.

CONCLUSIONS

These results suggest that genotype C is associated with more severe liver diseases than the B variant.

Bacterial lipoprotein induces tolerance in human THP-1 monocytes with reduced tumour necrosis factor α production via a CD14-independent pathway

Background

Endotoxin (lipopolysaccharide; LPS) tolerance is characterized by diminished production of tumour necrosis factor (TNF) α during prolonged exposure to LPS, and therefore represents an essential control mechanism during sepsis. However, it is unknown whether bacterial lipoprotein (BLP), another major component of bacterial walls, can cause tolerance. This study sought to determine whether BLP pretreatment can induce tolerance in human THP-1 monocytes.

Methods

Human THP-1 monocytic cells were pretreated with culture medium alone and medium containing LPS 10 ng ml−1 or BLP 10 ng ml−1 for 24 h. Cells were further stimulated with high doses (0·1–1 mg ml−1) of LPS or BLP for 6 h. TNF-α levels were determined by enzyme-linked immunosorbent assay. CD14 receptor expression on THP-1 monocytes was assessed by flow cytometry.

Results

When THP-1 cells were incubated with culture medium, BLP stimulation resulted in much higher TNF-α levels than LPS stimulation (P &lt; 0·05). Following LPS pretreatment, LPS stimulation-induced TNF-α production was significantly attenuated, whereas BLP stimulation still produced a small amount of TNF-α. However, BLP pretreatment prevented both LPS and BLP stimulation-induced TNF-α production from THP-1 cells. FACScan analysis revealed that THP-1 monocytes do not express CD14 receptor.

Conclusion

These results demonstrate that BLP has a more potent effect than LPS on THP-1 monocyte TNF-α production. Furthermore, BLP pretreatment is capable of inducing both BLP as well as LPS tolerance via a CD14-independent pathway, indicating a unique ability to cause cross-tolerance.

Dopamine attenuates neutrophil–endothelial interaction and is a putative anti-inflammatory cytokine

Background

Activated neutrophil (PMN) adherence to vascular endothelium comprises a key step for both transendothelial migration and initiation of potentially deleterious release of PMN products. Previous work has shown that the biogenic amine dopamine (DA) functions as an anti-inflammatory cytokine by inducing PMN apoptosis. The effect of DA on PMN transendothelial migration and adhesion receptor expression as well as on the endothelial molecules, E-selectin and intercellular adhesion molecule (ICAM) 1, was evaluated.

Methods

PMNs were isolated from healthy controls, stimulated with lipopolysaccharide (LPS) and tumour necrosis factor (TNF) α and treated with DA. CD11b and CD18 PMN adhesion receptor expression was assessed flow cytometrically. In a separate transwell experiment, the effect of the chemo-attractant peptide interleukin (IL) 8 on PMN migration was assessed. Human umbilical vein endothelial cells were stimulated with LPS/TNF-α, incubated with DA, and ICAM-1 and E-selectin endothelial molecule expression was assessed.

Results

There was a significant increase in transendothelial migration in stimulated PMNs as well as in CD11b/CD18, endothelial E-selectin and ICAM-1 expression compared with normal PMNs. DA attenuated these changes. The chemoattractant effect of IL-8 was also abolished.

Conclusion

These results show that DA attenuates the initial interaction between PMNs and endothelium, providing further evidence that it also functions as an anti-inflammatory cytokine.

Macrophages that have ingested apoptotic neutrophils release tissue inhibitor of matrix metalloproteinase 1

Background

Apoptosis of neutrophils (PMNs) in vivo is followed by their rapid uptake into adjacent phagocytic cells, a critical process in tissue remodelling, regulation of the immune response and resolution of inflammation. Tissue inhibitor of matrix metalloproteinase (TIMP) 1 is crucial in regulating the matrix-degrading properties of matrix metalloproteinases released by activated PMNs in inflammatory foci. The aim was to elucidate whether mononuclear-derived phagocytes (MDPs) release TIMP-1 and/or MMP-9 after phagocytosis of apoptotic PMNs.

Methods

MDPs were prepared from peripheral blood monocytes after isolation by culture in well plates for 7–10 days. PMNs were isolated from similarly healthy volunteers. PMN apoptosis was induced by 10 min of ultraviolet irradiation at 254 nm. After a further 6 h of incubation apoptosis was assessed and was routinely greater than 50 per cent. Apoptotic PMNs were then added to MDPs in specific ratios. After 1 h non-phagocytosed PMNs were washed away. RPMI was added to MDPs in well plates and 18 h later the supernatant was collected. Phagocytosis of opsonized zymosan, exposure to tumour necrosis factor (TNF) α and lipopolysaccharide (LPS), and finally MDPs alone were used as controls. TIMP-1 was quantified by enzyme-linked immunosorbent assay.

Results

TIMP-1 was released by MDPs after phagocytosis of apoptotic PMNs and opsonized zymosan. MDPs also produced TIMP-1 after stimulation with TNF-α–LPS. Levels of TIMP-1 from these MDPs were significantly different from those in MDPs alone.

Conclusion

Phagocytosis of apoptotic PMNs is an integral part of the host's attempt to resolve inflammation in altered immune states such as the systemic inflammatory response syndrome in which PMNs persistently release proinflammatory substances damaging the local microenvironment. This study has demonstrated that MDPs release TIMP-1 after phagocytosis of apoptotic PMNs and that this may play a role in the regulation of tissue remodelling and repair in response to inflammation.

Bacterial lipoprotein delays neutrophil apoptosis via a CD14-independent pathway

Background

Lipopolysaccharide (LPS) is considered the most potent exogenous mediator of the systemic inflammatory response syndrome (SIRS) which results, in part, from delayed neutrophil (PMN) apoptosis. The effects of another ubiquitous bacterial component, bacterial lipoprotein (BLP), the most abundant protein in the cell wall of all bacteria, on PMN apoptosis are unknown. The potential role of BLP in the regulation of PMN apoptosis was investigated and these effects were compared with those of LPS.

Methods

PMNs from healthy volunteers were isolated and exposed to identical concentrations of LPS and BLP in the presence or absence of recombinant antihuman CD14 monoclonal antibody. PMN apoptosis was assessed 6 hourly using Annexin V–propidium iodide staining and confirmed on cell morphology. PNM activation was assessed flow cytometrically using expression of functional markers CD11b and CD18.

Results

BLP significantly delayed PMN apoptosis and upregulated PMN adhesion receptor expression compared with control values. The effects seen were markedly similar to those of LPS.

Conclusion

BLP is capable of upregulating PMN adhesion receptor expression and delaying PMN apoptosis in a time- and dose-dependent manner independent of CD14. The potency, and the effects mediated by, BLP are very similar to those of LPS. This identifies BLP as a putative mediator of SIRS and demands that due attention be paid to other bacterial products in the investigation and treatment of septic states.

Bacterial lipoprotein induces endotoxin-independent tolerance to the systemic inflammatory response syndrome in vivo and in vitro

Background

Sublethal doses of endotoxin (lipopolysaccharide; LPS) induce tolerance in vivo and in vitro, and protect against the lethal effects of a further LPS challenge. Tolerance is characterized by diminished production of tumour necrosis factor (TNF) α. Bacterial lipoprotein (BLP), another bacterial wall component, might induce tolerance against its own lethal effects as well as those of endotoxin.

Methods

Ninety male MF-1 mice (mean(s.d.) weight 18(2) g) were randomized into three groups (n = 30 per group). Mice in group 1 received a single BLP-tolerant dose (10 mg kg−1) by intraperitoneal injection, whereas mice in group 2 received a second BLP-tolerant dose (10 mg kg−1) after 24 h. Following induction of tolerance, all mice were challenged with high doses of LPS 45 mg kg−1, BLP 45 mg kg−1 or a combination of LPS 30 mg kg−1 plus BLP 30 mg kg−1. Mice in group 3 were treated with a high dose of the above agents only. Mortality was assessed at 24 and 48 h. Macrophages were isolated from mice and pretreated in vitro with culture medium alone or culture medium containing LPS 10 ng ml−1 or BLP 10 ng ml−1 for 24 h. The cells were then stimulated with high doses (100–1000 ng ml−1) of LPS, BLP or LPS plus BLP for 6 h. The cell culture supernatants were collected and TNF-α levels were determined using enzyme-linked immunosorbent assay.

Results

BLP-induced tolerance significantly improved survival compared with that of mice without tolerance (P &lt; 0·05). In vitro, pretreatment of murine macrophages with BLP significantly attenuated LPS, BLP and LPS plus BLP stimulation-induced TNF-α production.

Conclusion

BLP mimics LPS in the development of the systemic inflammatory response syndrome. Furthermore, BLP is capable of inducing tolerance, both in vivo and in vitro, which subsequently prevents BLP- and LPS plus BLP-induced death.

Soluble interleukin 6 receptor (sIL-6R) mediates colonic tumor cell adherence to the vascular endothelium: a mechanism for metastatic initiation?

The mechanisms by which surgery increases metastatic proliferation remain poorly characterized, although endotoxin and immunocytes play a role. Recent evidence suggests that endothelial adherence of tumor cells may be important in the formation of metastases. Soluble receptors of interleukin-6 (sIL-6R) shed by activated neutrophils exert IL-6 effects on endothelial cells, which are unresponsive under normal circumstances. This study examined the hypothesis that sIL-6R released by surgical stress increases tumor cell adherence to the endothelium. Neutrophils (PMN) were stimulated with lipopolysaccharide, C-reactive protein (CRP), and tumor necrosis factor-alpha. Soluble IL-6R release was measured by enzyme-linked immunosorbent assay. Colonic tumor cells transfected with green fluorescent protein and endothelial cells were exposed to sIL-6R, and tumor cell adherence and transmigration were measured by fluorescence microscopy. Basal release of sIL-6R from PMN was 44.7 +/- 8.2 pg/ml at 60 min. This was significantly increased by endotoxin and CRP (131 +/- 16.8 and 84.1 +/- 5.3, respectively; both P < 0.05). However, tumor necrosis factor-alpha did not significantly alter sIL-6R release. Endothelial and tumor cell exposure to sIL-6R increased tumor cell adherence by 71.3% within 2 h but did not significantly increase transmigration, even at 6 h. Mediators of surgical stress induce neutrophil release of a soluble receptor for IL-6 that enhances colon cancer cell endothelial adherence. Since adherence to the endothelium is now considered to be a key event in metastatic genesis, these findings have important implications for colon cancer treatment strategies.

Effects of somatostatin, octreotide and pitressin plus nitroglycerine on systemic and portal haemodynamics in the control of acute variceal bleeding

To examine the haemodynamic effects of somatostatin (SS) and octreotide (OC) versus pitressin plus nitroglycerine (PN) in the control of variceal bleeding, 224 patients with acute oesophageal and gastric variceal haemorrhage were randomly divided into three groups and treated with SS, OC and PN; they also had their Doppler ultrasound parameters measured before, during and after treatment. The success rates of bleeding control in the SS (80.9%, 86.8% and 89.7%, p<0.001) and OC (75.3%, 80.8% and 84.9%, p<0.01) groups were significantly higher than in the PN group (51.8%, 59.0% and 65.1%) at 24, 48 and 72 hours respectively, and the average duration of SS (12.7 + 6.8 h) and OC (13.8 + 8.0 h) was significantly lower than that of PN (24.6 + 15.4 h, p<0.001). Side-effects of SS (7.4%) and OC (8.2%) were less than those of PN (41.0%, p<0.001 and p<0.01). The diameter of portal vein (PVD), velocity of portal vein (PVV), volume of portal blood flow (PVF) and hepatic artery pulsatility index (HA-PI) in all three groups decreased significantly during initial treatment, but recovered when treatment was stopped. Heart rate and cardiac output decreased significantly in patients treated with SS and OC; mean arterial pressure was unchanged. However, heart rate and mean arterial pressure increased, and cardiac output decreased, with PN. Somatostatin and octreotide were more effective than pitressin plus nitroglycerine in patients with acute variceal haemorrhage, with fewer side-effects, and may decrease PVF and portal vein pressure through reduction of cardiac output and dilatation of the visceral blood vessels.

Different excitation and reception distributions with a single-loop transmit-receive surface coil near a head-sized spherical phantom at 300 MHz

Calculations and experiments were used to examine the B(1) field behavior and signal intensity distribution in a 16-cm diameter spherical phantom excited by a 10-cm diameter surface coil at 300 MHz. In this simple system at this high frequency very complex RF field behavior exists, resulting in different excitation and reception distributions. Included in this work is a straightforward demonstration that coil receptivity is proportional to the magnitude of the circularly polarized component of the B(1) field that rotates in the direction opposite to that of nuclear precession. It is clearly apparent that even in very simple systems in head-sized samples at this frequency it is important to consider the separate excitation and reception distributions in order to understand the signal intensity distribution.

Characteristics of community-acquired methicillin-resistant Staphylococcus aureus in infants and children without known risk factors

This retrospective study sought to determine the characteristics of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections in patients younger than 18 years without known risk factors who were treated at a teaching hospital in central Taiwan. Epidemiological and clinical data were collected from medical charts. Possible risk factors included hospitalization within the past 6 months, transfer from other hospitals or nursing homes, and having underlying illness. A total of 173 isolates of community-acquired S. aureus were analyzed. Seventeen (9.8%) of these 173 isolates were methicillin-resistant S. aureus collected from patients without risk factors, 31 (17.9%) were methicillin-resistant S. aureus from patients with risk factors, and the other 125 (72.3%) were methicillin-susceptible S. aureus. Most isolates of community-acquired methicillin-resistant S. aureus collected from patients without risk factors (14/17, 82.4%) were obtained from the infected wounds of skin or soft tissues. Only 4 (23.5%) in 17 patients with isolates resistant to methicillin were prescribed antimicrobial therapy with glycopeptides. Nevertheless, all patients recovered without any long-term sequelae. These results highlight the fact that community-acquired methicillin-resistant S. aureus infections occur frequently in Taiwan among patients who have no established risk factors for this infection.

Fatal hepatic failure after emergence of the hepatitis B virus mutant during lamivudine therapy in a patient with liver cirrhosis

Lamivudine therapy for chronic hepatitis and decompensated liver cirrhosis related to the hepatitis B virus (HBV) resulted in improvement of liver function and inhibition of viral replication. Despite emergence of the HBV mutant, e-antigen seroconversion and improvement of liver function may be achieved with continuation of lamivudine therapy. Although hepatic decompensation has been reported in a few cases after the emergence of lamivudine-resistant mutants, fatal cases of non-transplant patients have only rarely been reported in the literature. Here, we describe a patient with HBV-related liver cirrhosis who died after a breakthrough infection with a lamivudine-resistant mutant. Hepatic failure and mortality developed after flare-up of severe hepatitis after 13 months of lamivudine treatment. Emergence of the HBV mutant with substitution of isoleucine for leucine at residue 426 (L4261) in combination with isoleucine for methionine at residue 550 (M5501) was observed at 10 and 13 months of treatment.

Preoperative staging of cervical carcinoma with MR imaging: a reappraisal of diagnostic accuracy and pitfalls

The purpose of this study was to assess the diagnostic accuracy and pitfalls of MR imaging in preoperative staging of cervical cancer. Magnetic resonance imaging was performed to determine the tumor staging for 41 patients with cervical carcinoma emphasizing tumor size, parametrial invasion, vaginal invasion, and lymph node metastases. According to the correlation of MR findings with surgical-pathological features, there was less than 5 mm discrepancy in the size in 29 of 34 tumors (85.3%) that were larger than 1 cm. In assessing parametrial invasion, vaginal invasion and lymph node metastases, MR imaging had an accuracy of 95, 83, and 86%, respectively. In determining stage of disease and differentiating operable (< or =stage IIA) from advanced disease (> or =stage IIB), MR imaging had an accuracy of 82.9 and 93%. Pitfalls leading to staging errors included difficulties in differentiating cancer foci from surrounding tissue edema and detecting microscopic tumor extension. Magnetic resonance imaging is accurate in the evaluation of parametrial invasion and differentiation of operable from advanced disease. The ability of MR imaging to detect microscopic extra-cervical tumor extension and differentiate cancer foci from surrounding tissue edema is not as reliable.

Percutaneous transsplenic embolization of esophageal and gastrio-fundal varices in 18 patients

AIM: Clinical application and potential complication of percutaneous transsplenic varices embolization (PTSVE) of esophageal or gastrio-fundal varices in patients with hepatocellular carcinoma (HCC) complicated with portal vein cancerous thrombosis (PVCT).

METHODS: 18 patients with HCC complicated with PVCT and esophageal or gastrio-fundal varices who underwent PTSVE were collected. The rate of success, complication, mortality of the procedure and postoperative complication were recorded and analyzed.

RESULTS: PTSVE were successfully performed in 16 of 18 cases, and the rate of success was 89%. After therapy erythrocyte counts decreased in all of the natunts. 5 of patients needed blood transfusion, 2 patients requiredsurgical intervention because of and 11 patients with ascites were alleviated by diuresis. Among these 18 patients, the procedure-related mortality was 11% (2/18), one died of acute hepatic failure on the forth day after procedure, another died of acute renal failure on the fifth day. The patients were follow up for 1~12 mo except one. 13 of them died of their tumors but none of them experienced variceal bleeding.

CONCLUSION: PTSVE is a relatively safe and effective method to treat esophageal or gastrio-fundal varices in HCC patients with PVCT when percutaneous transhepatic varices embolization (PTHVE) of varices is impossible.

Hepatitis C virus infection among teenagers in an endemic township in Taiwan: epidemiological and clinical follow-up studies

The aim of the study was to elucidate the epidemiological features of Hepatitis C virus (HCV) infection among teenagers in an endemic area by conducting a mass screening study. We also investigated the clinical outcome of the anti-HCV-positive subjects by conducting subsequent short-term and long-term follow-up studies. All 2837 students of two junior middle schools in Tzukuan, aged 13-16 years, were invited to be screened for anti-HCV, HBsAg, AST and ALT in October 1995. A total of 2726 (96%) students responded. Anti-HCV, HCV RNA and aminotransferase levels were evaluated among anti-HCV-positive students 1 month and 30 months later, respectively. A total of 38 (1.4%; M/F = 22/16) participants were anti-HCV-positive. The anti-HCV-positive students had higher rates of exposures to transfusion, anti-HCV-positive families and surgery. The prevalence (2.8%) of the 7 maritime villages was markedly higher than that (0.7%) of the other 8 villages (P < 0.001). Subsequent follow-up studies demonstrated that there might be 5 cases of acute or recent HCV infection, and 6 cases who had recovered from chronic HCV infection.

Bacterial wall products induce downregulation of vascular endothelial growth factor receptors on endothelial cells via a CD14-dependent mechanism: implications for surgical wound healing

INTRODUCTION

Vascular endothelial growth factor (VEGF) is a potent mitogenic cytokine which has been identified as the principal polypeptide growth factor influencing endothelial cell (EC) migration and proliferation. Ordered progression of these two processes is an absolute prerequisite for initiating and maintaining the proliferative phase of wound healing. The response of ECs to circulating VEGF is determined by, and directly proportional to, the functional expression of VEGF receptors (KDR/Flt-1) on the EC surface membrane. Systemic sepsis and wound contamination due to bacterial infection are associated with significant retardation of the proliferative phase of wound repair. The effects of the Gram-negative bacterial wall components lipopolysaccharide (LPS) and bacterial lipoprotein (BLP) on VEGF receptor function and expression are unknown and may represent an important biological mechanism predisposing to delayed wound healing in the presence of localized or systemic sepsis.

MATERIALS AND METHODS

We designed a series of in vitro experiments investigating this phenomenon and its potential implications for infective wound repair. VEGF receptor density on ECs in the presence of LPS and BLP was assessed using flow cytometry. These parameters were assessed in hypoxic conditions as well as in normoxia. The contribution of CD14 was evaluated using recombinant human (rh) CD14. EC proliferation in response to VEGF was quantified in the presence and absence of LPS and BLP.

RESULTS

Flow cytometric analysis revealed that LPS and BLP have profoundly repressive effects on VEGF receptor density in normoxic and, more pertinently, hypoxic conditions. The observed downregulation of constitutive and inducible VEGF receptor expression on ECs was not due to any directly cytotoxic effect of LPS and BLP on ECs, as measured by cell viability and apoptosis assays. We identified a pivotal role for soluble/serum CD14, a highly specific bacterial wall product receptor, in mediating these effects. The decreased VEGF receptor density on ECs accruing from the presence of bacterial wall products resulted in EC hyporesponsiveness to rhVEGF and significant abolition of VEGF-directed EC proliferation.

CONCLUSION

These findings suggest that the well-recognized relationship between bacterial sepsis and attenuated wound healing may be due, in part, to the directly suppressive effects of bacterial wall components on EC VEGF receptor expression and, consequently, EC proliferation.

A novel phosphorylcholine-coated contact lens for extended wear use

The preparation and characterisation of a new phosphorylcholine (PC)-coated silicone hydrogel contact lens for use in extended wear is described. The Michael-type addition of amines to acrylates forms the basis of the synthesis of a novel silicone-based macromer with hydrophilic functionality. It is demonstrated that this macromer can be combined with other silicone-based monomers, hydrophilic monomers and crosslinker to produce a contact lenses formulation. Examples of lenses with water contents of 33% and 46% are illustrated and their properties compared to other commercially available lenses. Materials with comparatively low modulus (<0.3 MPa) and adequate tear strength (>2-4MPa) with excellent elongation to break (>200%) can be obtained using this technology. In addition to the mechanical aspects. both the oxygen and solute permeabilities of the material can be controlled by the hydrophilic: hydrophobic monomer balance in the formulation. to obtain materials with attributes suitable for extended wear use. The PC coating is achieved by means of an in-mould coating (IMC) technique that produces a uniform and stable surface as determined by staining and XPS. The coating imparts both improved lens wettability (advancing contact angle of approximately 50 with virtually no hysteresis) and lower protein adsorption relative to the uncoated lens.

[Two kaempferol triglycosides from pericarps of Sophora japonica L]

OBJECTIVE

To study the flavonol triglycosides in the pericarps of Sophora japonica.

METHOD

Various chromatographic techniques were used to isolate and purify the constituents. The structures were elucidated by chemical evidence and spectral analysis, especially by 2D NMR experiments.

RESULTS

Two kaempferol triglycosides were isolated and identified as kaempferol 3-O-beta-D-sophoroside-7-O-alpha-L-rhamnoside and kaempferol 3-O-(2"-O-beta-D-glucosyl)-beta-D-rutinoside.

CONCLUSION

Both of them were reported in S. japonica for the first time.

Tamoxifen inhibits endothelial cell proliferation and attenuates VEGF-mediated angiogenesis and migration in vivo

INTRODUCTION

Angiogenesis is fundamental to tumour growth and vascular endothelial growth factor (VEGF) is one of the most potent proangiogenic cytokines known. We have previously demonstrated that tamoxifen reduces serum VEGF in certain cancer patients. We hypothesized that tamoxifen may attenuate the angiogenetic response to VEGF.

METHODS

Human dermal microvessel endothelial primary cell cultures (HMEC) were incubated with tamoxifen (1.25-5.0 microg) or vehicle. Cell proliferation was quantified using 5-bromo-2'-deoxyuridine (BrdU) labelling endothelial cell proliferation assay. The effect of oral tamoxifen (20 mg/day) on VEGF-mediated angiogenesis in vivo was assessed using a Matrigel angiogenesis assay in the Sprague-Dawley rat.

RESULTS

Tamoxifen (5.0 microg/ml) significantly reduced HMEC proliferation over 24 h when compared with cells treated with vehicle alone. Oral administration of tamoxifen in the rat (20 mg/day) significantly reduced endothelial cell proliferation and migration in response to VEGF.

CONCLUSION

Tamoxifen (5.0 microg/ml) reduces proliferation of a VEGF-dependent endothelial cell line in vitro. In vivo, orally administered tamoxifen reduces VEGF-mediated angiogenesis in the rat. These findings indicate that tamoxifen may directly inhibit the effect of VEGF on the endothelial cell, in addition to its previously described effect of reducing serum VEGF levels. This data supports a role for tamoxifen in modulation of the VEGF-dependent angiogenic response to surgical trauma, particularly as an adjuvant therapy for VEGF-dependent tumours.

Specificity of endothelial cell reorientation in response to cyclic mechanical stretching

Evidence suggests that cellular responses to mechanical stimuli depend specifically on the type of stimuli imposed. For example, when subjected to fluid shear stress, endothelial cells align along the flow direction. In contrast, in response to cyclic stretching, cells align away from the stretching direction. However, a few aspects of this cell alignment response remain to be clarified: (1) Is the cell alignment due to actual cell reorientation or selective cell detachment? (2) Does the resulting cell alignment represent a response of the cells to elongation or shortening, or both? (3) Does the cell alignment depend on the stretching magnitude or rate, or both? Finally, the role of the actin cytoskeleton and microtubules in the cell alignment response remains unclear. To address these questions, we grew human aortic endothelial cells on deformable silicone membranes and subjected them to three types of cyclic stretching: simple elongation, pure uniaxial stretching and equi-biaxial stretching. Examination of the same cells before and after stretching revealed that they reoriented. Cells subjected to either simple elongation or pure uniaxial stretching reoriented specifically toward the direction of minimal substrate deformation, even though the directions for the two types of stretching differed by only about 20 degrees. At comparable stretching durations, the extent of cell reorientation was more closely related to the stretching magnitude than the stretching rate. The actin cytoskeleton of the endothelial cell subjected to either type of stretching was reorganized into parallel arrays of actin filaments (i.e., stress fibers) aligned in the direction of the minimal substrate deformation. Furthermore, in response to equi-biaxial stretching, the actin cytoskeleton was remodeled into a "tent-like" structure oriented out of the membrane plane-again towards the direction of the minimal substrate deformation. Finally, abolishing microtubules prevented neither the formation of stress fibers nor cell reorientation. Thus, endothelial cells respond very specifically to the type of deformation imposed upon them.

Tourniquet-induced systemic inflammatory response in extremity surgery

BACKGROUND

Tourniquet-induced reperfusion injury in animals produces significant systemic inflammatory effects. This study investigated whether a biologic response occurs in a clinically relevant model of tourniquet-induced reperfusion injury.

METHODS

Patients undergoing elective knee arthroscopy were prospectively randomized into controls (no tourniquet) and subjects (tourniquet-controlled). The effects of tourniquet-induced reperfusion on monocyte activation state, neutrophil activation state, and transendothelial migration (TEM) were studied. Changes in the cytokines implicated in reperfusion injury, tumor necrosis factor-alpha, interleukin (IL)-1beta, and IL-10 were also determined.

RESULTS

After 15 minutes of reperfusion, neutrophil and monocyte activation were significantly increased. Pretreatment of neutrophils with pooled subject (ischemia-primed) plasma significantly increased TEM. In contrast, TEM was not significantly altered by ischemia-primed plasma pretreatment of the endothelial monolayer. Significant elevation of tumor necrosis factor-alpha and IL-1beta were observed in subjects compared with controls after 15 minutes of reperfusion. There was no significant difference in serum IL-10 levels between the groups at all the time points studied.

CONCLUSION

These results indicate a transient neutrophil and monocyte activation after tourniquet-ischemia that translates into enhanced neutrophil transendothelial migration with potential for tissue injury.

The angiogenic response to skeletal injury is preserved in the elderly

Angiogenesis is essential for normal bone formation and repair. Avascularity characterizes aberrant fracture union in the elderly, while angiogenic mechanisms during cutaneous wound repair are attenuated in aged humans. We hypothesized that skeletal injury results in local (circulating) and systemic (fracture site) 'angiogenic' responses and that these reparative mechanisms are attenuated with advanced patient age. This prospective study examined peripheral blood and fracture hematoma from 32 patients, 16 under 40 years and 16 over the age of 75, undergoing emergent surgery for isolated fracture. The angiogenic cytokines vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) were assayed. Endothelial cell cultures were supplemented with patient plasma and fracture hematoma and angiogenesis determined in vitro by measuring cell proliferation and blood vessel tube formation. Angiogenesis was determined in vivo using a murine dorsal wound pocket model and quantification of new blood vessel formation after 7 days. We found that all injured patients, irrespective of age, have elevated plasma and fracture hematoma levels of VEGF and PDGF. These elevated cytokine concentrations translate into biologically significant angiogenic effects, in vitro and in vivo. These effects are primarily VEGF mediated and are not dependent on patient age. The biological activity of these growth factors does not diminish with advanced age. Thus skeletal injury does result in local and systemic angiogenic responses whereby angiogenic cytokine availability and activity is preserved in the aged suggesting alternative mechanisms for the development of avascularity in delayed and fracture non-union in the elderly.