SRY-Box transcription factor 9 triggers YAP nuclear entry via direct interaction in tumors

The translocation of YAP from the cytoplasm to the nucleus is critical for its activation and plays a key role in tumor progression. However, the precise molecular mechanisms governing the nuclear import of YAP are not fully understood. In this study, we have uncovered a crucial role of SOX9 in the activation of YAP. SOX9 promotes the nuclear translocation of YAP by direct interaction. Importantly, we have identified that the binding between Asp-125 of SOX9 and Arg-124 of YAP is essential for SOX9-YAP interaction and subsequent nuclear entry of YAP. Additionally, we have discovered a novel asymmetrical dimethylation of YAP at Arg-124 (YAP-R124me2a) catalyzed by PRMT1. YAP-R124me2a enhances the interaction between YAP and SOX9 and is associated with poor prognosis in multiple cancers. Furthermore, we disrupted the interaction between SOX9 and YAP using a competitive peptide, S-A1, which mimics an α-helix of SOX9 containing Asp-125. S-A1 significantly inhibits YAP nuclear translocation and effectively suppresses tumor growth. This study provides the first evidence of SOX9 as a pivotal regulator driving YAP nuclear translocation and presents a potential therapeutic strategy for YAP-driven human cancers by targeting SOX9-YAP interaction.

Imatinib inhibits the malignancy of hepatocellular carcinoma by suppressing autophagy

Hepatocellular carcinoma (HCC) is one of the most common cancers and is associated with high morbidity and mortality rates. Recent research indicated that imatinib, a selective tyrosine kinase inhibitor, suppressed the growth of hepatocellular carcinoma. However, the effect of imatinib on HCC and its mechanism remain under investigated. In this study, we demonstrated that imatinib inhibited the proliferation, migration and invasion of HCC cells in vitro and exerted antitumour effects on HCC xenografts in mice in vivo. Imatinib treatment decreased the phosphorylation of AKT and increased the levels of both p62 (protein sequestosome 1) and LC3 (microtubule-associated protein 1A/1B-light chain 3) in HCC cells and HCC xenografts. Scanning confocal microscopy analysis with a mRFP-GFP-LC3 reporter and transmission electron microscopy analysis revealed that imatinib suppressed the autophagic flux by obstructing the formation of autolysosomes. Moreover, imatinib reversed the autophagy induced by sorafenib, and combined treatment with imatinib and sorafenib exerted a synergetic effect in HCC cells compared with monotherapy. Our collective data suggested that imatinib may target HCC by acting as an inhibitor of both tyrosine kinase and autophagy; here, we propose that imatinib could be a promising therapeutic agent for HCC in the clinic.

The Role of Bone Morphogenetic Protein 9 in Nonalcoholic Fatty Liver Disease in Mice

Background and Aims: It’s reported that bone morphogenetic protein 9 (BMP9) played an important role in lipid and glucose metabolism, but the role of BMP9 in nonalcoholic fatty liver disease (NAFLD) is unclear. Here, we evaluated the therapeutic efficacy of recombined BMP9 in NAFLD mice and investigated the potential mechanism.

Methods: The effects of recombinant BMP9 on NAFLD were assessed in HFD-induced NAFLD mice. C57BL/6 mice were administrated with high-fat diet (HFD) for 12 weeks. In the last 4 weeks, mice were treated with PBS or recombined BMP9 once daily. Insulin sensitivity was evaluated by glucose tolerance test (GTT) and insulin tolerance test (ITT) at the end of the 12th week. Then NAFLD related indicators were assessed by a variety of biological methods, including histology, western blotting, real-time PCR, RNA-seq and assay for transposase-accessible chromatin using sequencing (ATAC-seq) analyses.

Results: BMP9 reduced obesity, improved glucose metabolism, alleviated hepatic steatosis and decreased liver macrophages infiltration in HFD mice. RNA-seq showed that Cers6, Cidea, Fabp4 involved in lipid and glucose metabolism and Fos, Ccl2, Tlr1 involved in inflammatory response downregulated significantly after BMP9 treatment in HFD mouse liver. ATAC-seq showed that chromatin accessibility on promoters of Cers6, Fabp4, Ccl2 and Fos decreased after BMP9 treatment in HFD mouse liver. KEGG pathway analysis of dysregulated genes in RNA-seq and integration of RNA-seq and ATAC-seq showed that TNF signaling pathway and Toll-like receptor signaling pathway decreased in BMP9 treated HFD mouse liver.

Conclusion: Our data revealed that BMP9 might alleviate NAFLD via improving glucose and lipid metabolism, decreasing inflammatory response and reshaping chromatin accessibility in HFD mouse liver. BMP9 downregulate genes related to lipid metabolism, glucose metabolism and inflammation expression, at least partially via decreasing promoter chromatin accessibility of Cers6, Fabp4, Fos and Tlr1. BMP9 may also reduce the expression of liver Ccl2, thereby changing the number or composition of liver macrophages, and ultimately reducing liver inflammation. The effect of BMP9 on NAFLD might be all-round, and not limit to lipid and glucose metabolism. Therefore, the underlying mechanism needs to be studied in detail further.

miR-541 potentiates the response of human hepatocellular carcinoma to sorafenib treatment by inhibiting autophagy

OBJECTIVE

Autophagy participates in the progression of hepatocellular carcinoma (HCC) and the resistance of HCC cells to sorafenib. We investigated the feasibility of sensitising HCC cells to sorafenib by modulating miR-541-initiated microRNA-autophagy axis.

DESIGN

Gain- and loss-of-function assays were performed to evaluate the effects of miR-541 on the malignant properties and autophagy of human HCC cells. Autophagy was quantified by western blotting of LC3, transmission electron microscopy analyses and confocal microscopy scanning of mRFP-GFP-LC3 reporter construct. Luciferase reporter assays were conducted to confirm the targets of miR-541. HCC xenograft tumours were established to analyse the role of miR-541 in sorafenib-induced lethality.

RESULTS

The expression of miR-541 was downregulated in human HCC tissues and was associated with malignant clinicopathologic phenotypes, recurrence and survival of patients with HCC. miR-541 inhibited the growth, metastasis and autophagy of HCC cells both in vitro and in vivo. Prediction software and luciferase reporter assays identified autophagy-related gene 2A (ATG2A) and Ras-related protein Rab-1B (RAB1B) as the direct targets of miR-541. Consistent with the effects of the miR-541 mimic, inhibition of ATG2A or RAB1B suppressed the malignant phenotypes and autophagy of HCC cells. Furthermore, siATG2A and siRAB1B partially reversed the enhancement of the malignant properties and autophagy in HCC cells mediated by the miR-541 inhibitor. More interestingly, higher miR-541 expression predicted a better response to sorafenib treatment, and the combination of miR-541 and sorafenib further suppressed the growth of HCC cells in vivo compared with the single treatment.

CONCLUSIONS

Dysregulation of miR-541-ATG2A/RAB1B axis plays a critical role in patients' responses to sorafenib treatment. Manipulation of this axis might benefit survival of patients with HCC, especially in the context of the highly pursued strategies to eliminate drug resistance.

Ursolic Acid Improves Intestinal Damage and Bacterial Dysbiosis in Liver Fibrosis Mice

Liver fibrosis is a reversible process of extracellular matrix deposition or scar formation after liver injury. Intestinal damage and bacterial dysbiosis are important concomitant intestinal changes in liver fibrosis and may in turn accelerate the progression of liver fibrosis through the gut-liver axis. RhoA, an important factor in the regulation of the cytoskeleton, plays an important role in intestinal damage. We investigated the effects of ursolic acid (UA), a traditional Chinese medicine with anti-fibrotic effects, on intestinal damage and bacterial disorder through the RhoA pathway. UA treatment reduced intestinal damage by inhibiting the inflammatory factor TNF-α and increasing the expression of tight junction proteins and antibacterial peptides to protect the intestinal barrier. Moreover, the corrective effect of UA on bacterial dysbiosis was also confirmed by sequencing of the 16S rRNA gene. Potential beneficial bacteria, such as the phylum Firmicutes and the genera Lactobacillus and Bifidobacterium, were increased in the UA group compared to the CCl₄ group. In liver fibrosis mice with RhoA inhibition via injection of adeno-associated virus, the liver fibrosis, intestinal damage, and flora disturbances were improved. Moreover, UA inhibited the expression of RhoA pathway components. In conclusion, UA improves intestinal damage and bacterial dysbiosis partly via the RhoA pathway. This may be a potential mechanism by which UA exerts its anti-fibrotic effects and provides effective theoretical support for the future use of UA in clinical practice.

Autophagy inhibition enhanced 5‑FU‑induced cell death in human gastric carcinoma BGC‑823 cells

The exact molecular mechanism of 5-fluorouracil (5-FU) in human gastric cancer cells remains to be elucidated. Cultured BGC‑823 human gastric carcinoma and AGS cell lines were treated with 5‑FU. Autophagosome formation was investigated through multiple approaches, including the quantification of green fluorescent protein‑microtubule‑associated protein 1A/1B‑light chain 3 (LC3) puncta, LC3 conversion and electron microscopy observations. Additionally, autophagy was inhibited using 3‑methyladenine (3‑MA) and beclin‑1 ablation, to determine its role in 5‑FU‑mediated cell death. In addition, the present study assessed alterations in sirtuin expression following 5‑FU treatment with reverse transcription‑quantitative polymerase chain reaction. 5‑FU treatment induced apoptosis and inhibited proliferation in BGC‑823 and AGS gastric cancer cells. It is of note that the 5‑FU treatment only promoted autophagy in BGC‑823 cells. Additionally, inhibition of autophagy by either 3‑MA or beclin‑1 ablation increased 5‑FU‑induced cell death in BGC‑823 cells. The present study quantified changes in sirtuin (SIRT1, SIRT3, SIRT5, and SIRT6) expression following 5‑FU treatment and using a specific inhibitor, sirtinol, the present study investigated their involvement in 5‑FU‑mediated autophagy. Autophagy inhibition through manipulation of sirtuin proteins may increase the therapeutic efficacy of the 5‑FU chemotherapeutic drug against gastric carcinoma.

Ursolic acid suppresses TGF-β1-induced quiescent HSC activation and transformation by inhibiting NADPH oxidase expression and Hedgehog signaling

Activation of quiescent hepatic stellate cells (q-HSCs) and their transformation to myofibroblasts (MFBs) is a key event in liver fibrosis. Hedgehog (Hh) signaling stimulates q-HSCs to differentiate into MFBs, and NADPH oxidase (NOX) may be involved in regulating Hh signaling. The author's preliminary study demonstrated that ursolic acid (UA) selectively induces apoptosis in activated HSCs and inhibits their proliferation in vitro via negative regulation of NOX activity and expression. However, the effect of UA on q-HSCs remains to be elucidated. The present study aimed to investigate the effect of UA on q-HSC activation and HSC transformation and to observe alterations in the NOX and Hh signaling pathways during q-HSC activation. q-HSC were isolated from adult male Sprague-Dawley rats. Following culture for 3 days, the cells were treated with or without transforming growth factor-β1 (TGF-β1; 5 µg/l); intervention groups were pretreated with UA (40 µM) or diphenyleneiodonium chloride (DPI; 10 µM) for 30 min prior to addition of TGF-β1. mRNA and protein expression of NOX and Hh signaling components and markers of q-HSC activation were examined by western blotting and reverse transcription-polymerase chain reaction. TGF-β1 induced activation of q-HSCs, with increased expression of α-smooth muscle actin (α-SMA) and type I collagen. In addition, expression of NOX subunits (gp91^phox, p67^phox, p22^phox, and Rac1) and Hh signaling components, including sonic Hh, sterol-4-alpha-methyl oxidase, and Gli family zinc finger 2, were upregulated in activated HSCs. Pretreatment of q-HSCs with UA or DPI prior to TGF-β1 significantly downregulated expression of NOX subunits and Hh signaling components and additionally inhibited expression of α-SMA and type I collagen, thereby preventing transformation to MFBs. UA inhibited TGF-β1-induced activation of q-HSCs and their transformation by inhibiting expression of NOX subunits and the downstream Hh pathway.

Progenitor-like cells derived from mouse kidney protect against renal fibrosis in a remnant kidney model via decreased endothelial mesenchymal transition

Introduction

Pathophysiological changes associated with chronic kidney disease impair angiogenic processes and increase renal fibrosis. Progenitor-like cells derived from adult kidney have been previously used to promote regeneration in acute kidney injury, even though it remained unclear whether the cells could be beneficial in chronic kidney disease (CKD).

Methods

In this study, we established a CKD model by five-sixths nephrectomy and mouse kidney progenitor-like cells (MKPCs) were intravenously administered weekly for 5 weeks after establishing CKD. We examined the impact of MKPCs on the progression of renal fibrosis and the potential of MKPCs to preserve the angiogenic process and prevent endothelial mesenchymal transition in vivo and in vitro.

Results

Our results demonstrate that the MKPCs delayed interstitial fibrosis and the progression of glomerular sclerosis and ameliorated the decline of kidney function. At 17 weeks, the treated mice exhibited lower blood pressures, higher hematocrit levels, and larger kidney sizes than the control mice. In addition, the MKPC treatment prolonged the survival of the mice with chronic kidney injuries. We observed a decreased recruitment of macrophages and myofibroblasts in the interstitium and the increased tubular proliferation. Notably, MKPC both decreased the level of vascular rarefaction and prevented endothelial mesenchymal transition (EndoMT) in the remnant kidneys. Moreover, the conditioned medium from the MKPCs ameliorated endothelial cell death under hypoxic culture conditions and prevented TGF-β-induced EndoMT through downregulation of phosphorylated Smad 3 in vitro.

Conclusions

MKPCs may be a beneficial treatment for kidney diseases characterized by progressive renal fibrosis. The enhanced preservation of angiogenic processes following MKPC injections may be associated with decreased fibrosis in the remnant kidney. These findings provide further understanding of the mechanisms involved in these processes and will help develop new cell-based therapeutic strategies for regenerative medicine in renal fibrosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-015-0241-8) contains supplementary material, which is available to authorized users.

Efficiency enhancement of silicon solar cells using a nano-scale honeycomb broadband anti-reflection structure

This experiment demonstrates the process for manufacturing a ZnO honeycomb sub-wavelength structure using nanosphere lithography technology exhibiting excellent anti-reflection properties from the UV to NIR wavelength regions. This honeycomb nanostructure, combined with commercially available crystalline Si solar cells, show substantially improved conversion efficiency from 15.6% to 16.6% using optimized honeycomb sizes and precursor concentrations of ZnO. The present work develops an unsophisticated and economical technique suitable for industrial applications in producing a uniform and low-reflective texture.

Biomimetic nanostructured antireflection coating and its application on crystalline silicon solar cells

In this report, we demonstrate the implementation of biomimetic nanostructured antireflection coatings with polymethyl methacrylate (PMMA) layer on the micro-textured surface of silicon crystalline solar cells. To reduce cost, the process combines colloidal lithography, cast molding method, and reversal nanoimprint lithography. The technique is simple, low cost, and does not cause damage to the thin and brittle conventional crystalline solar cells. The antireflection properties of this biomimetic nanostructure coating are considered as effective as those of a conventional single-layer SiNx thin film. The resultant structures alone could reduce the average reflectance of solar cell from 13.2% to 7.8% and enhance power conversion efficiency from 12.85% to 14.2%.

Risk factors for extra-pulmonary tuberculosis compared to pulmonary tuberculosis

BACKGROUND

Tuberculosis (TB) continues to be a major global health problem. Extra-pulmonary TB (EPTB) manifests with protean symptoms, and establishing a diagnosis is more difficult than pulmonary TB (PTB).

SETTING

A university-affiliated hospital in southern Taiwan.

OBJECTIVE

To analyse the risk factors for EPTB compared with PTB.

DESIGN

This retrospective study compared patients with EPTB and PTB in southern Taiwan by analysing their demographic data and clinical underlying diseases. Risk factors for EPTB were further analysed.

RESULTS

A total of 766 TB patients were enrolled in this study, with 102 (13.3%) EPTB and 664 (86.7%) PTB cases. Of the 766 patients, 3% of PTB patients had EPTB, while 19.6% of EPTB patients also had PTB. The most frequently involved EPTB site was the bone and joints (24.5%). The incidence of EPTB vs. PTB decreased significantly for each decade increase in patient age. Multivariate logistic regression analysis showed that being female, not being diabetic, having end-stage renal disease and not smoking were independent risk factors for EPTB.

CONCLUSION

This study defines the risk factors for EPTB compared with PTB. Awareness of these factors is essential for physicians to have a high index of suspicion for accurate and timely diagnosis.

Tuberculous peritonitis in a haemodialysis patient with elevated serum CA 125 and hypercalcaemia

CA 125, a glycoprotein derived from coelomic epithelium, is used primarily as a marker of epithelial ovarian cancer. However, elevated levels of serum CA 125 have also been detected in other benign and malignant disorders. This study describes a haemodialysis patient who contracted tuberculous peritonitis associated with hypercalcaemia, erythropoietin-resistant anaemia and elevated CA 125, which normalised gradually following antituberculosis treatment. Tuberculous peritonitis should be considered in the differential diagnosis of ascites with elevated serum CA 125. Additionally, CA 125 is a useful marker for monitoring response to tuberculous peritonitis treatment.

Reconstruction after intercalary resection of malignant bone tumours

We reviewed 29 patients who had undergone intercalary resection for malignant tumours. Of these, 14 had received segmental allograft reconstruction and 15 extracorporeally-irradiated autograft.

At a mean follow-up of 71 months (24 to 132), 20 were free from disease, five had died and four were alive with pulmonary metastases. Two patients, one with an allograft and one with an irradiated autograft, had a local recurrence. Reconstruction with extracorporeally-irradiated autograft has a significantly lower rate of nonunion (7% vs 43%, p = 0.031) but an insignificantly higher rate of fracture (20% vs 14%, p = 0.535) than that with segmental allograft. Using the Enneking functional evaluation system, the mean postoperative score for the patients without local recurrence was 87% (80% to 96%) and was similar in both groups.

Extracorporeally-irradiated autograft could be an acceptable alternative for reconstruction after intercalary resection, especially in countries where it is difficult to obtain allografts.

Roles of PI3K in neutrophil function

Neutrophils are terminally differentiated cells that play a vital role in host defense. It has recently become evident that phospholipid regulation plays an import role in many neutrophil functions. We review the regulation of neutrophil functions such as chemotaxis, superoxide production, and phagocytosis by phosphatidylinositol-3,4,5-trisphosphate (PIP3), which is generated in neutrophils by PI3K(gamma). Several lines of evidence are presented demonstrating the importance of this kinase in regulating chemotaxis, in particular the directionality of chemotactic migration. Evidence suggesting that this kinase is important for phagocytosis, especially during engulfment and the internalization of large particles, is also reviewed. Finally, it is suggested that PI3K is important for superoxide production and neutrophil priming. The common link between these seemingly diverse functions is that PI3K(gamma), via its phospholipid products, appears to be providing spatial-temporal cues for the binding of actin-organizing proteins.

Treatment of malignant bone tumours by extracorporeally irradiated autograft-prosthetic composite arthroplasty

Autogenous bone graft which has been either autoclaved or irradiated is commonly used in oriental countries as an alternative to allograft. We started to use the technique of extracorporeal irradiation of the resected specimen and reimplantation (ECIR) in 1991. There was, however, a high incidence of fracture of the irradiated bone and loss of articular cartilage. In an attempt to reduce these complications, we combined the irradiated autograft with a conventional arthroplasty. Between 1995 and 1998, 14 patients underwent limb salvage by this method. Seven had an osteosarcoma, two bony metastases, three a chondrosarcoma, one a malignant fibrous histiocytoma, and one a leiomyosarcoma. Ten tumours were located in the proximal femur, two in the proximal humerus, and two in the distal femur. One patient who had a solitary metastasis in the proximal part of the left femur died from lung metastases 13 months after operation. The remaining 13 patients were alive and without evidence of local recurrence or distant metastases at a mean follow-up of 43 months (28 to 72). Postoperative palsy of the sciatic nerve occurred in one patient, but no complications such as wound infection, fracture, or nonunion were seen. All host-irradiated bone junctions healed uneventfully within eight months. Using the Enneking functional evaluation system, the mean postoperative score for all 14 patients was 80% (57 to 93). The use of irradiated autograft prosthesis composites reduces the complications of ECIR and gives good functional results. It may be a good alternative in limb-salvage surgery, especially in countries where it is difficult to obtain allografts.

Oral administration of IL-12 suppresses anaphylactic reactions in a murine model of peanut hypersensitivity

There is no satisfactory therapeutic intervention for peanut allergy, which accounts for most life-threatening food allergic reactions. Since IL-12 has been found to inhibit allergic airway responses in a mouse model of asthma and to cure Th2 cytokine-mediated murine schistosomiasis, we hypothesized that IL-12 treatment might also inhibit peanut allergic reactions. Consequently, we investigated the effects of oral IL-12 treatment in a murine model of peanut allergy and found that oral administration of liposome encapsulated rIL-12 could both prevent and reverse peanut hypersensitivity and could reduce histamine release, peanut-specific serum IgE and IgG1, and fecal IgA levels. Oral IL-12 treatment also increased IFN-gamma but did not decrease IL-4 or IL-5 levels. We conclude that oral rIL-12 treatment has therapeutic as well as preventive effects on peanut allergy, which are associated with increased IFN-gamma production.

Differential regulation of T cell receptor-mediated Th1 cell IFN-gamma production and proliferation by divergent cAMP-mediated redox pathways

Culture of an H-2(s)-restricted, bovine myelin basic protein (BMBP)-specific murine Th1 clone with the adenyl cyclase agonist forskolin (FSK) or isobutylmethylxanthine (IBMX), an inhibitor of cAMP catabolism, before culture with anti-CD3 or BMBP and antigen-presenting cells (APC) suppressed antigen or anti-CD3-induced proliferation and production of interferon-gamma (IFN-gamma). Other H-2(s)-derived or H-2(b)-derived clones specific for BMBP or keyhole limpet hemocyanin (KLH) were similarly affected. FSK did not affect the expression of CD4 or the T cell receptor (TCR) but did diminish levels of the phosphorylated (activated) mitogen-activated protein (MAP) kinases early response kinase-1 (ERK-1) and ERK-2. Immunoblotting of lysates from an FSK-treated Th1 clone with antibodies to a carboxy-terminal epitope of p56(lck), a signal transduction enzyme upstream from ERK-1 and ERK2, did not detect p56(lck) unless the lysates were reduced prior to electrophoresis. Immunoblotting of nonreduced lysates with antibodies to an amino-terminal epitope demonstrated p56(lck) with a lower apparent molecular weight, characteristic of oxidized proteins. Reduction restored the detection of p56(lck) by anticarboxy-terminal p56(lck) and to mobilities indistinguishable from controls detected by the antiamino-terminal p56(lck). N-acetylcysteine or catalase prevented FSK-induced suppression of antigen-induced proliferation and the loss of carboxy-terminal epitopes of p56(lck). An inhibitor of cAMP-dependent protein kinase A (PKA) or nitric oxide synthase (NOS) did not affect FSK-induced inhibition of antigen-induced proliferation. In contrast, inhibitors of PKA or NOS, but not catalase, prevented FSK-induced suppression of IFN-gamma production. Moreover, immunoblots of lysates precipitated with anti-p56(lck), phosphotyrosine, or CD4 demonstrated that in FSK-treated, anti-CD3-stimulated cells, p56(lck) is not associated with CD4 zeta chain, nor is p56(lck) or zeta chain phosphorylated. In vitro kinase assays demonstrated that p56(lck) from FSK-treated cells does not have kinase activity. Taken together, the results suggest that an elevation of intracellular cAMP (in the absence of antigen) creates an oxidative environment that oxidizes and inactivates p56(lck) by an H(2)O(2)-dependent, PKA-independent mechanism and inhibits the production of IFN-gamma by an NO, PKA-dependent mechanism. Thus, antigen-induced proliferation and IFN-gamma production in a Th1 clone are controlled separately by different cAMP-dependent, redox-based mechanisms.

Abnormal migration phenotype of mitogen-activated protein kinase-activated protein kinase 2-/- neutrophils in Zigmond chambers containing formyl-methionyl-leucyl-phenylalanine gradients

Time-lapsed video microscopy and confocal imaging were used to study the migration of wild-type (WT) and mitogen-activated protein kinase-activated protein kinase 2 (MK2-/-) mouse neutrophils in Zigmond chambers containing fMLP gradients. Confocal images of polarized WT neutrophils showed an intracellular gradient of phospho-MK2 from the anterior to the posterior region of the neutrophils. Compared with WT neutrophils, MK2-/- neutrophils showed a partial loss of directionality but higher migration speed. Immunoblotting experiments showed a lower protein level of p38 mitogen-activated protein kinase and a loss of fMLP-induced extracellular signal-related kinase phosphorylation in MK2-/- neutrophils. These results suggest that MK2 plays an important role in the regulation of neutrophil migration and may also affect other signaling molecules.

Food Allergy Herbal Formula-1 (FAHF-1) blocks peanut-induced anaphylaxis in a murine model

BACKGROUND

Peanut allergy is a major cause of fatal and near-fatal anaphylactic reactions to foods. There is no curative therapy for this condition. Traditional Chinese medicines have been reported to have antiallergic properties, which might be useful for treating peanut allergy.

OBJECTIVE

The purpose of this study was to investigate the effects of a Chinese herbal formula, FAHF-1, on peanut anaphylactic reactions in a mouse model of peanut allergy.

METHODS

Mice were sensitized with freshly ground whole peanut in the presence of cholera toxin and boosted 1 and 3 weeks later. FAHF-1 treatment was initiated 1 week later and continued for 7 weeks. After treatment, mice were challenged with peanut, and anaphylactic symptoms, body temperatures, and plasma histamine and IgE levels were measured. T-cell proliferative responses and cytokine production were also determined.

RESULTS

FAHF-1 completely blocked peanut-induced anaphylactic symptoms and markedly reduced mast cell degranulation and histamine release. Peanut-specific serum IgE levels were significantly reduced by 2 weeks of treatment at the time of challenge, and they remained lower 4 weeks after discontinuation of treatment. FAHF-1 significantly reduced peanut-induced lymphocyte proliferation as well as IL-4, IL-5, and IL-13 synthesis but not IFN-gamma synthesis. No toxic effects on liver or kidney functions were observed, nor was there any overall immune suppression.

CONCLUSION

FAHF-1 protected peanut-sensitized mice from anaphylactic reactions and significantly reversed established IgE-mediated peanut allergy. This suggests that FAHF-1 might prove valuable for the treatment of peanut allergy.

Surgical treatment for Haglund's deformity

Haglund's deformity, or "pump bump" is a common cause of posterior heel pain, characterized clinically by a painful soft tissue swelling at the level of the Achilles tendon insertion. We reviewed 30 heels in 19 patients with failure of conservative treatment. Surgical management consisted of excision of the posterior calcaneal tuberosity and bursectomy through a medial longitudinal incision. The average follow-up period was 6 years (range, 3-10 years). Only 3 heels (10%) in 2 patients had persistent pain. Twenty-seven heels (90%) were cured after operation. However, 25 heels (83%) had residual pain for a half to two years after operation and became free of symptoms thereafter. We conclude surgical treatment of Haglund's deformity produces a predictably good result (90%) but requires a long time about a half to two years for full recovery.

Eosinophilic meningitis caused by Angiostrongylus cantonensis: report of 17 cases

PURPOSE

To describe two outbreaks of Angiostrongylus cantonensis infection that occurred in Kaohsiung, Taiwan, during 1998 and 1999, and to characterize the source of the outbreaks and the clinical manifestations of the disease.

SUBJECTS AND METHODS

We performed a retrospective cohort study among Thai laborers with eosinophilic meningitis who ate raw snails (Ampullarium canaliculatus), as well as an environmental surveillance of larvae in snails.

RESULTS

We enrolled 17 Thai laborers in whom severe headache and eosinophilia developed within 4 to 23 days after eating raw snails. Twelve (71%) developed eosinophilic meningitis. Third-stage larvae were found in the cerebrospinal fluids of 2 patients and in all 12 tested snails. Specific antibodies to A. cantonensis were detected in serum from 16 of the patients and in cerebrospinal fluid from 5 of the patients. Central nervous system manifestations included headache (n = 17 [100%]), fever (n = 11 [65%]), Brudzinski's sign/stiff neck (n = 11 [65%]), hyperesthesia (n = 3 [18%]), cranial nerve palsy (n = 2 [12%]), diplopia (n = 2 [12%]), and ataxia (n = 1 [6%]). Laboratory findings included peripheral eosinophilia (n = 15 [88%]) and cerebrospinal fluid eosinophilia (n = 12 [71%]); elevated immunoglobulin (Ig) E levels (n = 13 [100%]); and transient increases in white blood cell count (n = 7 [41%]) and in serum levels of creatine kinase (n = 7 [41%]), transaminase (n = 3 [18%]), and lactate dehydrogenase (n = 2 [12%]). The severity of illness and eosinophilia were correlated with the number of ingested snails. Meningeal and basal ganglion enhancement was noted on magnetic resonance imaging in several patients. Treatment with mebendazole combined with glucocorticosteroids appeared to shorten the course of the infection, but not the number of relapses. The eosinophil count fell to normal within 3 months, but IgE levels remained elevated for as long as 6 months. All patients recovered with minimal neurologic sequelae.

CONCLUSION

Eosinophilic meningitis caused by A. cantonensis should be considered in patients who have headache or central nervous system manifestations after eating raw snails.

Intertrochanteric fractures in adults younger than 40 years of age

This study reviewed 66 intertrochanteric fractures in patients younger than 40 years old (average 33.0 years old; range 17-40 years old). In contrast to the usual population with intertrochanteric fractures, the factors male predominance (46/66), less pre-injury comorbidity (9/66), more outdoor high energy trauma (47/66), and more associated injuries (32/66) were evident. The distribution of associated injuries was wide. Some of them were life threatening. According to Boyd's classification, 20 were type I, 24 were type II, 13 were type III, and 9 were type IV. Twenty-nine were stable, and 37 were unstable. Stratified by the mechanism of injury, the difference in distribution between the subgroups was significant (p = 0.027, two-tail Fisher's exact test). Simple falls only caused Boyd type I and II fractures. Boyd type III or IV fractures were found more often after vehicular trauma or falls from a height. All the intertrochanteric fractures healed on average 70.5 days (range 31-213 days) after operation. The fractures resulting from vehicular trauma or fall from a height healed significantly more slowly (p = 0.02, univariant log-rank test). There were 6 intertrochanteric fracture-related complications. The mechanism of injury determines the character of intertrochanteric fractures in young adults. Given tougher bone stock, better healing ability, and less co-morbidity, proper management can lead to healing of all intertrochanteric fractures. The extent of functional recovery was also determined by the associated injuries.

Comparative study of the efficacy and safety of valaciclovir versus acyclovir in the treatment of herpes zoster

Acyclovir, a specific and selective inhibitor of the replication of Herpesviridae family, has well-documented efficacy and tolerability in the treatment of herpes zoster. Its limited oral bioavailability and short half-life, however, necessitates frequent dosing. Valaciclovir, the l-valyl ester of acyclovir, could be rapidly converted to acyclovir after oral administration, resulting in a three- to five-fold increase in acyclovir bioavailability compared with oral acyclovir in humans. Valaciclovir allows less frequent dosing and maintains the safety profiles of the parent drug. During the period from October 1996 through May 1998, a randomized, prospective study was performed in the Kaohsiung Veterans General Hospital to compare the safety and efficacy of valaciclovir with acyclovir in the treatment of herpes zoster in Taiwanese patients. Patients presenting with herpes zoster within 72 h after the onset of rash were enrolled and randomized to receive one of the following treatments: 1000 mg valaciclovir three times daily for 7 days or acyclovir 800 mg five times daily for 7 days. Patients were followed up for 29 days beginning with the start of therapy. A total of 57 patients were enrolled and randomized to receive valaciclovir (n = 32) or acyclovir (n = 25). Five patients in the valaciclovir group and three in the acyclovir group did not complete the study. The intent-to-treat analysis (57 patients) showed that valaciclovir significantly accelerated the resolution of herpes zoster-associated pain compared with acyclovir; on day 29, the valaciclovir group was 23% superior to the acyclovir group. There was no clinically significant difference in the nature, frequency or severity of adverse events between these two groups, although one and three adverse events were reported in the acyclovir and valaciclovir group, respectively. Thus, we conclude that in the management of herpes zoster, valaciclovir accelerates the resolution of pain and offers a simpler dosing, and maintains the favorable safety profile of acyclovir.

Legionnaires' disease in an immunocompetent young adult

Infection with Legionella pneumophila (LP) is a rare cause of pneumonia in previously healthy young adults. Pleural effusion is relatively common in Legionnaires' disease but is usually clinically insignificant. Herein we describe an immunocompetent, 19-year-old female with LP respiratory infection that presented with pleural effusion and mild interstitial infiltrates in the lower lungs. She received 3 weeks' treatment with erythromycin and rifampin and recovered completely. Diagnosis was based on serology testing with a four-fold rise of the antibody titer in the acute and convalescent phase. Legionnaires' disease should be considered in the differential diagnosis of culture-negative pleural effusion in immunocompetent young adults.

A systematic approach to the complete study of a signaling molecule: ribosomal p90rsk as an example

Ribosomal p90rsk is a kinase of central importance in transducing mitogenic signals from an activated receptor to the cell nucleus and for protein synthesis. Here, we analyze the optimal steps to fully describe this kinase in both normal neutrophils and leukemic cell lines. These are: (i) immunological analyses (immunoblotting and immunoprecipitation); (ii) enzyme activity assays (in vitro and "in-gel"); and (iii) immunobiochemical combination methods (immunoprecipitation/kinase assay, immunoprecipitation/"in-gel" assay and ion exchange chromatography/immunoblotting). For the enzyme assays, we describe a novel method to measure ribosomal p90rsk kinase activity "in-gel", based on a renatured-protein method that allows for the direct quantitation of enzyme activity. Finally, we present an algorithm that can be readily implemented to the quantification of the extent of stimulation of a kinase in response to a particular extracellular stimuli. In our case, it was found that activation of p90rsk was higher in proliferating leukemic cells than in mature neutrophils, indicating that a suppression of key signal transduction links could contribute to the maturational arrest typical of acute leukemia. All the techniques and strategies described here for p90rsk could be easily extrapolated to the study of any signal transduction molecule, provided it has a phosphotransferase activity.

Murine model of atopic dermatitis associated with food hypersensitivity

BACKGROUND

Atopic dermatitis (AD) is an eczematous skin eruption that generally begins in early infancy and affects up to 12% of the population. The cause of this disorder is not fully understood, although it is frequently the first sign of atopic disease and is characterized by an elevated serum IgE level, eosinophilia, and histologic tissue changes characterized early by spongiosis and a CD4(+) T(H)2 cellular infiltrate. Hypersensitivity to foods has been implicated as one causative factor in up to 40% of children with moderate-to-severe AD.

OBJECTIVE

The purpose of this study was to establish a murine model of food-induced AD.

METHODS

Female C3H/HeJ mice were sensitized orally to cow's milk or peanut with a cholera toxin adjuvant and then subjected to low-grade allergen exposure. Histologic examination of skin lesions, allergen-specific serum Ig levels, and allergen-induced T-cell proliferation and cytokine production were examined.

RESULTS

An eczematous eruption developed in approximately one third of mice after low-grade exposure to milk or peanut proteins. Peripheral blood eosinophilia and elevated serum IgE levels were noted. Histologic examination of the lesional skin revealed spongiosis and a cellular infiltrate consisting of CD4(+) lymphocytes, eosinophils, and mast cells. IL-5 and IL-13 mRNA expression was elevated only in the skin of mice with the eczematous eruption. Treatment of the eruption with topical corticosteroids led to decreased pruritus and resolution of the cutaneous eruption.

CONCLUSION

This eczematous eruption resembles AD in human subjects and should provide a useful model for studying immunopathogenic mechanisms of food hypersensitivity in AD.

Leukocyte-specific gene 1 protein (LSP1) is involved in chemokine KC-activated cytoskeletal reorganization in murine neutrophils in vitro

Leukocyte-specific gene 1 protein (LSP1) is a cytoskeletal-associated protein of leukocytes that in vitro cross-links F-actin into extensively branched bundles of mixed polarity. In this study, we examined chemotaxis and superoxide production in neutrophils prepared from wild-type (WT) and Lsp1 knockout mice. Compared to WT neutrophils, Lsp1-/- neutrophils showed impairment in both migration speed and chemotaxis direction during chemokine KC-directed chemotaxis. When examined by confocal microscopy, chemotaxing Lsp1-/- neutrophils showed abnormal morphologies. They had discontinuous primary actin-rich cortexes and large membrane protrusions. When stimulated by phorbol 12-myristate 13-acetate (PMA), Lsp1-/- peritoneal neutrophils produce more superoxide than WT. The data presented suggest that LSP1 plays important roles in the regulation of neutrophil morphology, motility, and superoxide production.

Characteristics of heavy metals on particles with different sizes from municipal solid waste incineration

Information on the concentration and size distribution of particles in the flue gas streams is essential for selecting and designing particle removal systems. Two municipal solid waste incinerators (MWIs) were selected for conducting flue gas sampling to determine the particulate distribution and heavy metals concentration on particles with different sizes by US EPA Method 5 sampling train and a cascade impactor. In addition, the characteristics of heavy metals contained on particles were investigated via isokinetic sampling of flue gas stream of air pollution control devices (APCDs). The experimental results indicated that average particulate matter (PM) concentrations at APCDs inlet were 2288.2+/-825.9 and 3069.2+/-810. 0mg/Nm(3), while the concentrations of PM at stack were 1.51+/-0.20 and 14.81+/-4.52mg/Nm(3) in MWI-A and MWI-B, respectively. The differential mass size distribution of PM and differential elemental size distribution of Zn, Pb, and Cu in front of APCDs were of bimodal forms. Results indicate that Zn>Pb>Cu in order of mass concentration in each stage. The fine particles represent approximately 70% and the coarse particles account for the rest 30% of total particulate matters collected on eight stages for both incinerators. Zn, Pb and Cu on fine particles account for approximately 80% and those on the coarse particles are less than 20% of the total heavy metals collected on eight stages of the cascade impactor for both incinerators.

Serum withdrawal-induced post-transcriptional stabilization of cyclooxygenase-2 mRNA in MDA-MB-231 mammary carcinoma cells requires the activity of the p38 stress-activated protein kinase

Overexpression of the cyclooxygenase-2 (COX-2) gene is observed in several neoplastic diseases. However, molecular mechanisms involved in the regulation of expression of COX-2 are not well understood. In this report, we describe a unique post-transcriptional regulatory mechanism of COX-2 mRNA stabilization in MDA-MB-231 cells, a highly metastatic cell line derived from a human mammary tumor. High levels of COX-2 mRNA, protein, and enzyme activity were induced by serum withdrawal, which were potently inhibited by the addition of serum or >100-kDa serum factor. Nuclear run-on analysis and actinomycin D chase experiments indicate that regulation is primarily at the level of post-transcriptional mRNA stability. Interestingly, SB203580, an inhibitor of the p38 stress-activated protein kinase (SAPK), and overexpression of the dominant-negative p38alpha construct potently inhibited the serum withdrawal-induced COX-2 mRNA levels. Indeed, the half-life of COX-2 mRNA decreased from 9 to 4.5 h after SB203580 treatment, suggesting that signal transduction by the p38 SAPK pathway is required for COX-2 mRNA stability.

CpG oligodeoxynucleotides can reverse Th2-associated allergic airway responses and alter the B7.1/B7.2 expression in a murine model of asthma

CpG oligodeoxynucleotides (CpG-ODN) administered during Ag sensitization or before Ag challenge can inhibit allergic pulmonary inflammation and airway hyperreactivity in murine models of asthma. In this study, we investigated whether CpG-ODN can reverse an ongoing allergic pulmonary reaction in a mouse model of asthma. AKR mice were sensitized with conalbumin followed by two intratracheal challenges at weekly intervals. CpG-ODN was administered 24 h after the first Ag challenge. CpG-ODN administration reduced Ag-specific IgE levels, bronchoalveolar lavage fluid eosinophils, mucus production, and airway hyperreactivity. We found that postchallenge CpG-ODN treatment significantly increased IFN-gamma concentrations and decreased IL-13, IL-4, and IL-5 concentrations in bronchoalveolar lavage fluids and spleen cell culture supernatants. Postchallenge CpG-ODN treatment also increased B7.1 mRNA expression and decreased B7.2 mRNA expression in lung tissues. These results suggest that CpG-ODN may have potential for treatment of allergic asthma by suppressing Th2 responses during IgE-dependent allergic airway reactions. The down-regulation of Th2 responses by CPG-ODN may be associated with regulation of the costimulatory factors B7.1 and B7.2.

The chinese herbal medicine formula MSSM-002 suppresses allergic airway hyperreactivity and modulates TH1/TH2 responses in a murine model of allergic asthma

BACKGROUND

Asthma is a major public health problem worldwide, and the morbidity and mortality of asthma have increased in the past two decades. The reputed efficacy, low cost, and relative absence of side effects of traditional Chinese medicines (TCMs) have led to increasing interest in the use of TCMs for the treatment of asthma in Western countries. However, there are few well-controlled scientific studies on the efficacy, safety, and mechanisms of action of TCMs used to treat asthma.

OBJECTIVE

The goal of this study was to investigate the effects of the Chinese herbal medicine formula MSSM-002, derived from TCMs used to treat allergic asthma, on a well-characterized mouse model of allergic asthma.

METHODS

Mice sensitized intraperitoneally and challenged intratracheally with conalbumin were treated with MSSM-002 24 hours after the first intratracheal challenge. Dexamethasone-treated, saline solution sham-treated, and naive mice served as controls. The effects of MSSM-002 on allergic airway hyperreactivity, inflammation, antigen-specific antibody production, lung histologic features, and cytokine profiles were evaluated.

RESULTS

MSSM-002 treatment virtually eliminated airway hyperreactivity and markedly reduced the total number of cells and the percent eosinophils in bronchoalveolar lavage fluids compared with the sham-treated group. Lung histologic features showed that MSSM-002 reduced inflammation and mucus production. These effects were equivalent to the effects of dexamethasone, but in contrast to the overall immunosuppressive effects of dexamethasone MSSM-002 treatment decreased antigen-specific IgE, IL-4, IL-5, and IL-13 levels without suppressing IgG2a and IFN-gamma synthesis.

CONCLUSION

MSSM-002 exhibits anti-airway hyperresponsiveness, anti-airway inflammation, and immunoregulatory effects on T(H)1/T(H)2 responses, which may be useful for treatment of allergic asthma.

Roles of phospholipid signaling in chemoattractant-induced responses

Chemoattractants, including chemokines, play a central role in regulation of inflammatory reactions by attracting and activating leukocytes. These molecules have been found to regulate metabolism of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P(2)) via phospholipase C (PLC) and phosphoinositide 3-kinase (PI3K). Recent studies of mouse lines that lack PLC-(beta)2, PLC-(beta)3, or PI3K(gamma) demonstrate that chemoattractants act through PLC-(beta)2 and PLC-(beta)3 to hydrolyze PtdIns(4,5)P(2) and through PI3K(gamma) to phosphorylate PtdIns(4,5)P(2) in mouse neutrophils. These studies also confirmed the importance and revealed new roles of these signaling pathways in chemoattractant-induced responses.

A murine model of peanut anaphylaxis: T- and B-cell responses to a major peanut allergen mimic human responses

BACKGROUND

Peanut allergy affects 0.6% of the US population. At the present time, allergen avoidance is the only therapeutic option. Animal models of food-induced anaphylaxis would facilitate attempts to design novel immunotherapeutic strategies for the treatment of peanut allergy.

OBJECTIVE

The purpose of this study was to develop a murine model of IgE-mediated peanut hypersensitivity that closely mimics human peanut allergy.

METHODS

C3H/HeJ mice sensitized orally with freshly ground whole peanut and cholera toxin as adjuvant were challenged orally 3 and 5 weeks later with crude peanut extract. Anaphylactic reactions were determined. T- and B-cell responses to Ara h 1 and Ara h 2, the major peanut allergens, were characterized by evaluating splenocyte proliferative responses and IgE antibody concentrations. Furthermore, IgE antibodies in the sera of patients with peanut allergy and mice were compared for antibody binding to Ara h 2 isoforms and allergenic epitopes.

RESULTS

Peanut-specific IgE was induced by oral peanut sensitization, and hypersensitivity reactions were provoked by feeding peanut to sensitized mice. The symptoms were similar to those seen in human subjects. Ara h 1- and Ara h 2-specific antibodies were present in the sera of mice with peanut allergy. Furthermore, these Ara h 2-specific IgE antibodies bound the same Ara h 2 isoforms and major allergenic epitopes as antibodies in the sera of human subjects with peanut allergy. Splenocytes from mice with peanut allergy exhibited proliferative responses to Ara h 1 and Ara h 2.

CONCLUSION

This murine model of peanut allergy mimics the clinical and immunologic characteristics of peanut allergy in human subjects and should be a useful tool for developing immunotherapeutic approaches for the treatment of peanut allergy.

Open total talar dislocation--report of two cases

Total dislocation of talus from all its surrounding joints (tibiotalar, subtalar and talonavicular) is an extremely rare injury. Because of its rarity, only few case reports can be found in the literature. In the review of the literature, infection and AVN are the most commonly encountered complications that affect the outcome of these severe injuries. Herein we report two cases of open total talar dislocation. Immediate debridement, reduction of the talus, and primary skin closure was done followed by cast immobilization. After more than 2 years follow up, neither infection nor AVN was found. We conclude that reimplantation of the talus is preferable if the wound is relatively clean. Talectomy, or combined with tibiocalcaneal fusion should be reserved for later salvage procedure.

Evaluation on speciation and removal efficiencies of mercury from municipal solid waste incinerators in Taiwan

Two large-scale municipal solid waste incinerators (MWIs) located in Taiwan were selected for conducting flue gas sampling to determine the chemical speciation of mercury by both USEPA Method 29 and Ontario Hydro Method (OHM). In addition, the emission characteristics and removal efficiencies of mercury were evaluated via isokinetic sampling of flue gas upstream and downstream of APCDs. Results indicated that the average removal efficiencies of Hg for MWI-A and MWI-B were 29.56 and 44.70%, respectively. In terms of mercury speciation by USEPA Method 29 and Ontario Hydro Method (OHM), oxidized mercury (Hg2+), in the flue gas was predominant at the inlet of APCD for both incinerators. Less than 30% of mercury in the flue gas existed in the elemental form (Hg0) at APCD inlet. Mercury emitted from the stack also predominated as a form of Hg2+ in MWI-A. Approximately 90% of total mercury emission from the stack existed in the form of Hg2+ for MWI-A. Due to the higher removal efficiency of soluble mercury (Hg2+) in wet scrubber, less total Hg was actually emitted from MWI-B than MWI-A. Regarding the removal efficiency of Hg0 in the flue gas, the APCDs of MWI-A (DSI + FF) had a higher removal efficiency than that of MWI-B (ESP + WS) possibly due to the reduction of Hg2+ which occurred in the wet scrubber.

P47(phox)-deficient NADPH oxidase defect in neutrophils of diabetic mouse strains, C57BL/6J-m db/db and db/+

Deficiencies in neutrophil NADPH oxidase proteins have been demonstrated in humans with chronic granulomatous disease. However, no spontaneous mutation in murine NADPH oxidase has been reported. In this study we report that neutrophils from the diabetic mouse strains, C57BL/6J-m heterozygous lean (lepr(db/+)) and homozygous obese (lepr(db/db)) mice produced no superoxide on stimulation. An absence of intact p47(phox) but not other oxidase proteins was observed in both mouse strains through the use of immunoblotting. Molecular analysis by reverse transcriptase-polymerase chain reaction identified three abnormal p47phox mRNA transcripts. Sequencing of genomic DNA of p47(phox) revealed a point mutation at the -2 position of exon 8, which is consistent with aberrant splicing of the p47(phox) transcript. These results indicate that the C57BL/6J-m db/db and db/+ mice are the first spontaneously derived murine model of NADPH oxidase deficiency involving a p47(phox) mutation.

Strain-dependent induction of allergic sensitization caused by peanut allergen DNA immunization in mice

To investigate the potential application of allergen gene immunization in the modulation of food allergy, C3H/HeSn (C3H) mice received i.m. injections of pAra h2 plasmid DNA encoding one of the major peanut allergens, Ara h2. Three weeks following pDNA immunization, serum Ara h2-specific IgG2a, IgG1, but not IgE, were increased significantly in a dose-dependent manner. IgG1 was 30-fold higher in multiply compared with singly immunized mice. Ara h2 or peanut protein injection of immunized mice induced anaphylactic reactions, which were more severe in multiply immunized mice. Heat-inactivated immune serum induced passive cutaneous anaphylaxis, suggesting that anaphylaxis in C3H mice was mediated by IgG1. IgG1 responses were also induced by intradermal injection of pAra h2, and by i.m. injection of pOMC, the plasmid DNA encoding the major egg allergen protein, ovomucoid. To elucidate whether the pDNA immunization-induced anaphylaxis was a strain-dependent phenomenon, AKR/J and BALB/c mice also received multiple i.m. pAra h2 immunizations. Injection of peanut protein into these strains at weeks 3 or 5 following immunization did not induce reactions. Although IgG2a was increased significantly from week 2 in AKR/J mice and from week 4 in BALB/c mice and remained elevated for at least 6 wk, no IgG1 or IgE was detected. These results indicate that the type of immune responses to pDNA immunization in mice is strain dependent. Consequently, models for studying human allergen gene immunization require careful selection of suitable strains. In addition, this suggests that similar interindividual variation is likely in humans.

A murine model of IgE-mediated cow's milk hypersensitivity

BACKGROUND

Cow's milk allergy (CMA) is one of the leading causes of food allergy in children. Understanding the mechanisms involved in the development of CMA has been hampered by the lack of suitable animal models.

OBJECTIVE

We sought to develop a mouse model of IgE-mediated cow's milk hypersensitivity (CMH) that mimics the clinical features of immediate CMA in humans.

METHODS

Three-week-old C3H/HeJ mice were sensitized by intragastric administration of cow's milk (CM) plus cholera toxin and boosted 5 times at weekly intervals.

RESULTS

CM-specific IgE antibody levels were significantly increased at 3 weeks and peaked at 6 weeks after the initial feeding. Intragastric challenge with CM at week 6 elicited systemic anaphylaxis accompanied by vascular leakage, significantly increased plasma histamine, and increased intestinal permeability to casein. Histologic examination of intestinal tissue revealed marked vascular congestion, edema, and sloughing of enterocytes. The role of IgE in mediating CMH was confirmed by abrogation of passive cutaneous anaphylaxis reactions by heat inactivation of immune sera. Development of IgE-mediated CMH in this model is likely to be TH2 cell mediated because in vitro stimulation of spleen cells from mice allergic to CM induced significant increases in the levels of IL-4 and IL-5, but not IFN-gamma.

CONCLUSION

This model should provide a useful tool for evaluating the immunopathogenic mechanisms involved in CMA and for exploring new therapeutic approaches.

Acute closed humeral shaft fractures treated with dynamic compression plate

BACKGROUND

To define the efficacy of dynamic compression plates (DCPs) for the treatment of closed humeral shaft fractures.

METHODS

A total of 165 patients with closed humeral shaft fractures were studied retrospectively. There were 120 patients who underwent open reduction and internal fixation with DCPs and no bone grafting (BG). Forty-five patients received the same procedures with BG. The mean follow-up period was 93 months.

RESULTS

In the DCP without BG group, the average blood loss was 350 ml, operation time was 105 minutes, hospital stay was 8.5 days and fracture union time was 13.5 weeks. In the DCP with BG group, the average blood loss was 525 ml, operation time was 115 minutes, hospital stay was 7.9 days and fracture union time was 9.2 weeks.

CONCLUSIONS

In our experience, DCPs are effective for surgical fixation of humeral shaft fractures. Prophylactic BG is recommended for cases with more comminution.

Heterotopic ossification after cemented or uncemented bateman bipolar hemiarthroplasty

BACKGROUND

This is a retrospective study to evaluate the incidence of heterotopic ossification (HO) in cemented and uncemented femoral neck fractures treated with Bateman bipolar hemiarthroplasty.

METHODS

From October 1985 to July 1990, there were 451 cases of displaced intracapsular fractures of the femoral neck treated with Bateman bipolar hemiarthroplasty (261 uncemented vs 190 cemented) at the Veterans General Hospital-Taipei.

RESULTS

After an average follow-up of 46 months, there was more HO in the cemented group than in the uncemented group (p = 0.014, chi-squared test). The average surgical time was approximately 20 minutes longer and the average blood loss was approximately 160 ml more in the cemented Bateman bipolar hemiarthroplasty group.

CONCLUSIONS

HO formation is more common in cemented Bateman bipolar hemiarthroplasty than in the uncemented procedure. The incidence of HO is not related to age or sex.

The role of p38 MAP kinase in TGF-beta1-induced signal transduction in human neutrophils

Transforming growth factor-beta 1 (TGF-beta 1) is the strongest chemoattractant yet described for human neutrophils. It activates neither phospholipase C nor phospholipase D. It does not induce rises in intracellular calcium, degranulation, or superoxide production. The signaling pathways utilized by TGF-beta 1 are largely unknown. This report demonstrates that TGF-beta 1 activates p38 MAP kinase. The kinase inhibitor SB203580 blocks the chemotactic responses as well as actin polymerization induced by TGF-beta 1. Potential cellular targets of the p38 MAP kinase pathway which could mediate these function are discussed.

p38 mitogen-activated protein kinase activation is required for human neutrophil function triggered by TNF-alpha or FMLP stimulation

Mitogen-activated protein (MAP) kinase-mediated signal-transduction pathways convert extracellular stimulation into a variety of cellular functions. However, the roles of MAP kinases in neutrophils are not well understood yet. Protein phosphorylation analysis of cellular MAP kinases indicates that exposure of human neutrophils to chemotactic factor FMLP as well as granulocyte-macrophage CSF, PMA, or ionomycin rapidly induced the activation of p38 and p44/42 MAP kinases, but stimulation with inflammatory cytokine TNF-alpha triggered the activation of p38 MAP kinase only. To study the cellular functions of these MAP kinases, the inhibitor SB20358, which specifically inhibited enzymatic activity of cellular p38 MAP kinase, and the inhibitor PD98059, which specifically blocked the induced protein phosphorylation and activation of p44/42 MAP kinase in intact neutrophils, were utilized. Inhibition of the cellular p38 MAP kinase activation almost completely abolished the TNF-alpha-stimulated IL-8 production and superoxide generation of human neutrophils. In addition, the FMLP-induced neutrophil chemotaxis as well as superoxide generation were suppressed markedly by inhibiting the activation of cellular p38 MAP kinase, but not p44/42 MAP kinase. Moreover, RIA indicates that the activation of cellular p38 MAP kinase was required for the neutrophil IL-8 production stimulated by granulocyte-macrophage CSF or LPS as well as TNF-alpha, but not for that induced by PMA or ionomycin. These results demonstrate that the activation of cellular p38 MAP kinase is indispensable for the TNF-alpha- or FMLP-mediated cellular functions in human neutrophils, and suggest that p38 MAP kinase may play a different role in response to distinct stimulation.

Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: a prospective, randomized trial

To determine the efficacy and tolerability of an enteric-coated peppermint-oil formulation (Colpermin), we conducted a prospective, randomized, double-blind, placebo-controlled clinical study in 110 outpatients (66 men/44 women; 18-70 years of age) with symptoms of irritable bowel syndrome. Patients took one capsule (Colpermin or placebo) three to four times daily, 15-30 min before meals, for 1 month. Fifty-two patients on Colpermin and 49 on placebo completed the study. Forty-one patients on Colpermin (79%) experienced an alleviation of the severity of abdominal pain (29 were pain-free); 43 (83%) had less abdominal distension, 43 (83%) had reduced stool frequency, 38 (73%) had fewer borborygmi, and 41 (79%) less flatulence. Corresponding figures for the placebo group were: 21 patients (43%) with reduced pain (4 were pain-free), 14 (29%) with reduced distension, 16 (32%) with reduced stool frequency, 15 (31%) with fewer borborygmi, and 11 (22%) with less flatulence. Symptom improvements after Colpermin were significantly better than after placebo (P < 0.05; Mann-Whitney U-test). One patient on Colpermin experienced heartburn (because of chewing the capsules) and one developed a mild transient skin rash. There were no significant changes in liver function test results. Thus, in this trial, Colpermin was effective and well tolerated.

Segmental tibial fractures treated with interlocking nails. A retrospective study of 33 cases

We treated 33 segmental tibial fractures with interlocking nails between 1986 and 1991. All fractures were managed with calcaneal traction, closed reduction, reaming and fixation with a Grosse-Kempf interlocking nail. The patients were followed for at least 15 months. The mean duration to union was 17 (12-20) weeks for the distal fractures and 20 (12-34) weeks for the proximal ones. There were only 3 cases of delayed union of the proximal fracture, 2 of which united after dynamization by removal of distal screws and 1 after autogenous bone grafting. There were 2 cases of deep infection, which were diagnosed after the fractures were united. The infection was treated with removal of the nail, reaming, and antibiotic treatment intravenously for 2 weeks and orally for 4 weeks. All patients returned to their previous activity level. We conclude that segmental tibial fractures can be treated with an interlocking nail and have a high rate of union and a low complication rate.

High expression and activation of MAP kinase-activated protein kinase 2 in cardiac muscle cells

Recently, three mammalian mitogen-activated protein (MAP) kinases, ERK, SAPK/JNK, and p38/HOG-1 have been identified, each with apparently unique signal transduction pathways. The p38 MAP kinase mediates an intracellular stress-activated signaling pathway by regulating down-stream molecules, such as MAP kinase-activated protein (MAPKAP) kinase 2. To study the tissue specificity of MAPKAP kinase 2, mRNA blots containing multiple human tissues were hybridized with a specific oligonucleotide probe corresponding to human MAPKAP kinase 2. The Northern blot analysis revealed that two mRNA species of MAPKAP kinase 2, with sizes of 4.8 and 3.3 kb, were expressed in high levels in both human heart and skeletal muscle tissues. To better understand how MAPKAP kinase 2 is regulated in myocardium, cultured rat cardiac myoblast (H9c2) cells were stimulated with heat shock, H2O2-induced oxidative stress, or phorbol ester (PMA). Enzymatic activity of cellular MAPKAP kinase 2 in the cell lysates was evaluated using an in vitro kinase assay. Exposure of H9c2 cells to heat shock or oxidative stress induced a transient increase of cellular MAPKAP kinase 2 activity, which reached its peak level within 5 min. In contrast, stimulation of H9c2 cells with PMA, a potential myocardial hypertrophic factor, induced a sustained increase of cellular MAPKAP kinase 2 activity that was detectable for over 1 h. In addition, in vitro protein phosphorylation analysis with recombinant MAPKAP kinase 2 showed that small heat shock protein (hsp25) served as a major substrate molecule for the kinase in H9c2 cells and the protein phosphorylation of cellular hsp25 was stimulated by H2O2-induced oxidative stress or PMA treatment in intact H9c2 cells. Moreover, exposure of H9c2 cells to H2O2-induced oxidative stress or PMA rapidly activated cellular p38 MAP kinase as detected by the induced protein phosphorylation of the kinase. Taken together, these results strongly suggest that MAPKAP kinase 2 may be involved in stress-activated signal transduction in myocardium.

LSP1 is the major substrate for mitogen-activated protein kinase-activated protein kinase 2 in human neutrophils

In intact cells, mitogen-activated protein kinase-activated protein (MAPKAP) kinase 2 is rapidly activated by various cytokines, stresses, and chemotactic factors. The small heat shock protein p27 has been shown to be a substrate for MAPKAP kinase 2. Recently, we identified a novel substrate, designated p60, for MAPKAP kinase 2 in human neutrophils (Zu, Y.-L., Ai, Y., Gilchrist, A., Labadia, M. E., Sha'afi, R. I., and Huang, C.-K. (1996) Blood 87, 5287-5296). To further understand the signaling pathway of MAPKAP kinase 2, we have purified p60 from a heat-treated neutrophil lysate by DEAE-cellulose chromatography and SDS-polyacrylamide gel electrophoresis. Microsequencing of five peptides derived from purified p60 indicates that p60 is lymphocyte-specific protein 1 (LSP1). Furthermore antibodies specific for human and mouse LSP1 react with human and mouse p60. The sequence of human LSP1 indicates two serine residues at positions 204 and 252 as potential phosphorylation sites. The amino acid sequences surrounding these two sites are in agreement with the consensus sequence (Xaa-Xaa-Hyd-Xaa-Arg-Xaa-Xaa-Ser-Xaa-Xaa) for phosphorylation by MAPKAP kinase 2. Both serine residues in human LSP1 and the corresponding conserved serine residues in mouse LSP1 are in the basic C-terminal F-actin binding domain. Various fusion proteins of wild type and truncated mouse LSP1 with glutathione S-transferase were tested for their capacity to be phosphorylated by MAPKAP kinase 2. The results indicate that LSP1 is a substrate for MAPKAP kinase 2 in vitro and that the phosphorylation sites are located in the basic C-terminal domain of LSP1. Because both the small heat shock proteins and LSP1 are F-actin binding proteins, these results suggest a role for MAPKAP kinase 2 in the regulation of cytoskeletal structure or function.

Ischemic preconditioning triggers the activation of MAP kinases and MAPKAP kinase 2 in rat hearts

While much is known about the beneficial effects of myocardial stress adaptation, relatively less information is available about the adaptive mechanisms. To explore the signaling pathways of stress adaptation, isolated working rat hearts were divided into three groups. Group I was adapted to stress by conventional technique of repeated ischemia and reperfusion consisting of 5 min of ischemia followed by 10 min of reperfusion, repeated four times. Group II was treated with 100 microM of genistein, a tyrosine kinase inhibitor, followed by preconditioning as described for group I. The third group, perfused with buffer only for 60 min, served as control. All hearts were subjected to 30 min of ischemia followed by 30 min of reperfusion. The results of our study demonstrated better postischemic myocardial functions in the preconditioned hearts as evidenced by increased aortic flow, coronary flow, developed pressure and lesser amount of tissue injury as evidenced by the decreased creatine kinase release. The preconditioning effects were associated with enhancement of phospholipase D activity in the heart. The preconditioning effect was almost abolished by the genistein treatment which also prevented the enhancement of phospholipase D activities. Additionally, preconditioning of the rat hearts stimulated protein kinase C, MAP kinase, and MAPKAP kinase 2 activities which were inhibited by genistein. The results identifies for the first time tyrosine kinase-phospholipase D as potential signaling pathway for ischemic preconditioning, and implicates the involvement of multiple protein kinases in myocardial adaptation to ischemia.

Tumour necrosis factor-alpha-induced phosphorylation and activation of cytosolic phospholipase A2 are abrogated by an inhibitor of the p38 mitogen-activated protein kinase cascade in human neutrophils

The role of the newly identified p38 mitogen-activated protein kinase (MAP kinase) in terminally differentiated cells, such as human neutrophils, is totally unknown. In order to examine the possible role of this MAP kinase in the phosphorylation and activation of cytoplasmic phospholipase A2 (cPLA2), we tested the effect of the recently synthesized inhibitor of p38 MAP kinase, SB 203580, on the phosphorylation and activation of both p38 MAP kinase and cPLA2. We found that while tumour necrosis factor-alpha (TNF-alpha)-stimulated tyrosine phosphorylation of p38 MAP kinase is affected only slightly by SB 203580, its stimulated kinase activity is greatly reduced in human neutrophils in suspension treated with this inhibitor. Furthermore, the TNF-alpha-stimulated phosphorylation and activation of cPLA2 are completely abolished in cells treated with SB 203580. Based on these data, it is reasonable to conclude that an SB 203580-sensitive kinase, or kinases and/or phosphatases, are involved in the phosphorylation and activation of cPLA2 in intact human neutrophils in suspension stimulated by TNF-alpha. The possible role of the p38 MAP kinase cascade in the phosphorylation and activation of cPLA2 is discussed.

Activation of MAP kinase-activated protein kinase 2 in human neutrophils after phorbol ester or fMLP peptide stimulation

In response to extracellular stimulation, one of the earliest events in human neutrophils is protein phosphorylation, which mediates signal transduction and leads to the regulation of cellular functions. Mitogen-activated protein (MAP) kinases are rapidly activated by a variety of mitogens, cytokines, and stresses. The activated MAP kinases in turn regulate their substrate molecules by phosphorylation. MAP kinase-activated protein (MAPKAP) kinase 2, a Ser/Thr kinase, has been shown to be phosphorylated by p38 MAP kinase both in vivo and in vitro. Phosphorylation of the Thr-334 site of MAPKAP kinase 2 results in a conformational change with subsequent activation of the enzyme. To better define the role of MAPKAP kinase 2 in the activation of human neutrophils, its enzymatic activity was measured after stimulation by either a phorbol ester (phorbol myristate acetate [PMA]), a potent protein kinase C activator, or the tripeptide fMLP, which is a chemotactic factor. The in vitro kinase assays indicate that both PMA and fMLP stimulated a transient increase in the enzymatic activity of cellular MAPKAP kinase 2. The induced kinase activation was concentration-dependent and reached a maximum at 5 minutes for PMA and 1 minute for fMLP. To identify potential substrate molecules for MAPKAP kinase 2, a highly active kinase mutant was generated by mutating the MAP kinase phosphorylation site in the C-terminal region. The replacement of threonine 334 with alanine resulted in a marked augmentation of catalytic activity. Analysis of in vitro protein phosphorylation in the presence of the active kinase indicates that a 60-kD cytosolic protein (p60) was markedly phosphorylated and served as the major substrate for MAPKAP kinase 2 in human neutrophils. Based on the MAPKAP kinase 2 phosphorylation site of Hsp27, a competitive inhibitory peptide was synthesized. This competitive inhibitory peptide specifically inhibited MAPKAP kinase 2 enzymatic activity, as well as the in vitro and in vivo kinase-induced p60 phosphorylation. To assess the contribution of MAPKAP kinase 2 in neutrophil function, the oxidative burst response after manipulation of endogenous kinase activity was measured. Intracellular delivery of the competitive inhibitory peptide into human neutrophils reduced both PMA- and fMLP-stimulated superoxide anion production. Thus, the results strongly suggest that MAPKAP kinase 2 is involved in the activation of human neutrophils.