Sternal resection and reconstruction for metastasis due to breast cancer: the Marlex sandwich technique and implantation of a pedicled latissimus dorsi musculocutaneous flap

Background

The treatment of hemotogenous solitary sternal metastases by breast cancer remains a controversial issue. Sternal resection for select patients might provide good long-term local control.

Case presentation

A 63-year-old woman was admitted to our hospital with a mass at the sternum and right second to third costochondral cartilage. She had undergone bilateral mastectomy for breast cancer 13 years earlier. A percutaneous biopsy was performed, and the mass was diagnosed as solitary metastasis due to breast cancer. She received two courses of weekly paclitaxel and bevacizumab, and computed tomography (CT) revealed shrinking of the mass in the sternum. We performed surgical resection with curative intent for a multimodality approach. Parasternectomy and removal of the right second and third costochondral cartilage was performed. A prosthesis was created to fill the defect by sandwiching molded methylmethacrylate between polypropylene mesh. The prosthesis was fixed to the cut ends of the costochondral cartilage and the residual sternum. Finally, a harvested latissimus dorsi myoctaneous flap was transpositioned to cover the chest midline wound. Negative surgical margins at the stump of the sternum and costochondral cartilage were revealed.

Conclusion

Parasternal resection and reconstruction by the Marlex sandwich technique and implantation of a pedicled latissimus dorsi myocutaneous flap for metastasis due to breast cancer was safely performed.

[Three Cases of Resectable Advanced Gastric Cancer Treated with Neoadjuvant Chemotherapy]

Three patients diagnosed with HER2-negative resectable advanced gastric cancer with extensive regional lymph node metastases were treated with neoadjuvant chemotherapy(NAC), followed by gastrectomy with D2lymph node dissection. One patient received four 21-day courses of S-1 plus oxaliplatin(G-SOX), and pathological effect(PE)was Grade 3. Two patients received four 21-day courses of capecitabine plus oxaliplatin(CapeOX), and each PE was Grade 2and Grade 1a, respectively. One patient in poor PE was with recurrent liver and peritoneal metastases. This suggested that for resectable advanced gastric cancer with extensive regional lymph node metastases, NAC by SOX or CapeOX was effective for some patients.

[A Case of HER2-Positive Unresectable Gastric Cancer with Multiple Lymph Node and Liver Metastases Controlled Effectively by Combination Chemotherapy with Capecitabine, Oxaliplatin, and Trastuzumab]

A 77-year-old woman was diagnosed with HER2-positive unresectable gastric cancer with multiple lymph node and liver metastases(cT3-4, cN3, cM1[HEP, LYM], cStage IV ). Four courses of combination chemotherapy with capecitabine, oxaliplatin, and trastuzumab(XELOX plus Tras)were administered. Though all lesions showed a complete or partial response, anorexia and body weight loss appeared because of the stenosis in the primary gastric lesion. After another course, these symptoms became worse and she underwent laparoscopic gastrojejunostomy. She progressed favorably after the surgery, her anorexia improved and her weight increased. Thirty-four days after the surgery, the same chemotherapy was continued. At present, the metastases are well controlled 12months after the initial treatment. It is suggested that XELOX plus Tras is an effective chemotherapy regimen for HER2-positive unresectable gastric cancer.

Serum retinol levels are associated with brain volume loss in patients with multiple sclerosis

Background

Although predicting future brain volume loss (BVL) in patients with multiple sclerosis (MS) is important, studies have shown only a few biomarkers that can predict BVL.

Objectives

The aim of this study is to elucidate the association between longitudinal BVL and serum biomarker candidates.

Methods

This single-center, retrospective, observational study intended to cover MS patients during January 2008 to March 2016. Patients who underwent brain MRI two times at intervals of >24 months and had a blood test to measure biomarker candidates at the time or within three months of the MRI scan were included. Evaluation of brain volume was performed by using SIENAX and SIENA in the FMRIB software library.

Results

Twenty-three patients with MS were included in this study. We found that serum retinol binding protein (RBP) levels were significantly correlated with percentage brain volume change (PBVC) (p = 0.0079). Furthermore, best subset selection of multiple linear regression models identified baseline normalized brain volume and serum RBP as the best predictors of PBVC.

Conclusions

Our study shows that lower serum retinol levels are associated with greater longitudinal BVL and that serum RBP and can be a predictor of BVL.

Significance of Development and Reversion of Collaterals on MRI in Early Neurologic Improvement and Long-Term Functional Outcome after Intravenous Thrombolysis for Ischemic Stroke

BACKGROUND AND PURPOSE

Predicting response to rtPA is essential in the era of endovascular therapy for stroke. The purpose of this study was to elucidate prognostic factors of early neurologic improvement and long-term outcome with respect to the development and reversion of leptomeningeal collaterals in recanalization therapy after acute ischemic stroke.

MATERIALS AND METHODS

We analyzed consecutive patients with proximal MCA occlusion treated with rtPA from 2007 to 2012 at 2 hospital stroke centers. All patients routinely underwent brain MR imaging before rtPA. To assess the reversion of collateral signs, we included patients who underwent follow-up MR imaging. We assessed the development and reversion of collaterals by using a combination of 2 MR imaging collateral markers, the hyperintense vessel sign and the posterior cerebral artery laterality sign. Early neurologic improvement was defined as a decrease in the NIHSS score of ≥10 or a score of ≤2 at 24 hours of treatment.

RESULTS

Early neurologic improvement was observed in 22 of 48 eligible patients. The development of collaterals at arrival (15/22 versus 9/26, P = .042) was significantly associated with early neurologic improvement. Multivariate analysis adjusting for other variables showed that the development of collaterals at arrival (OR, 4.82; 95% CI, 1.34-19.98; P = .015) was independently associated with early neurologic improvement. Reversion of collaterals was significantly associated with successful recanalization (P < .001), and multivariate analysis showed that the reversion of collaterals was an independent prognostic factor of long-term functional outcome (OR, 5.07; 95% CI, 1.38-22.09; P = .013).

CONCLUSIONS

Our results indicate that the development of leptomeningeal collaterals plays a crucial role in achieving early neurologic improvement, and reversion of collaterals predicts a favorable outcome via arterial recanalization after rtPA treatment for acute stroke.

Development of a new palladium catalyst supported on phenolic resin

Palladium catalyst supported on phenolic resin: stable to oxygen and water, repeatedly usable, easily prepared and recovered from the reaction mixture and deformed on demand.

[A difficult to treat case of malignant peritoneal mesothelioma with peritoneal metastasis]

A 57-year-old man presented with abdominal discomfort. A computed tomography (CT) scan revealed a tumor, with a maximum diameter of approximately 5 cm, in the transverse mesocolon near the splenic flexure as well as a small nodular shadow suggestive of peritoneal dissemination on the greater omentum. Fluorodeoxyglucose (FDG)-positron emission tomography (PET) showed marked accumulations of FDG at the same sites. Laparoscopic examination revealed an elastic hard tumor, with a maximum diameter of slightly over 5 cm, at the posterior sheath of the transverse mesocolon and a small nodule on the greater omentum with apparent dissemination. Since radical surgery was considered to be difficult to perform, we only resected the disseminated nodule for diagnostic purposes. The final pathological diagnosis was biphasic- type (mixed epithelial and sarcomatoid type) malignant mesothelioma arising from the peritoneum. Approximately 20 days postoperatively, the patient received combination therapy with pemetrexed and cisplatin with a 3-week interval between the courses. Image assessment after completion of the third course revealed enlargement of the tumor mass and worsening of the peritoneal dissemination. Therefore, the treatment was switched to paclitaxel, which has been reported to be effective as a second-line therapy. The drug was scheduled to be administered on days 1, 8, and 15. However, after the first course on day 1, the patient's condition gradually deteriorated and he subsequently died.

Elevated expression of ETS-1 gene in a metastatic, tumorigenic human prostate epithelial cell line transformed by the v-Ki-ras oncogene

A suitable in vitro model system to investigate mechanisms of human prostate carcinogenesis is much needed. We have previously demonstrated that an immortal, but non-tumorigenic, human prostate epithelial cell line (267B(1)) can be malignantly transformed by the v-Ki-ras oncogene, and it can serve as a useful model for investigation of the progression steps of prostate carcinogenesis. In this study, we report for the first time the invasive/metastatic phenotype of the v-Ki-ras transformed 267B, cells (267B(1)/Ki-ras). In addition, comparing non-tumorigenic 267B, and metastatic tumorigenic 267B(1)/Ki-ras human prostate epithelial cell lines, we have found that expression of ETS-1 and ERGB mRNA was elevated to 2-5 fold in the metastatic and tumorigenic 267B(1)/Ki-ras cell line. A specific ETS-1 monoclonal antibody E44 also revealed that the expression of ETS-1 protein level in 267B(1)/Ki-ras cell line was higher than those in 267B, cell line. However, other members of the ETS gene family such as ETS-2, GABP alpha and their mRNA expression levels were similar in both cell lines. The activation of MAP kinase, a downstream target for Ki-ras, was also shown. The expression of urokinase plasminogen activator (u-PA) was also increased in the metastatic 267B(1)/Ki-ras line. An obvious capability of invasion was observed in the 267B(1)/Ki-ras cell line, but not in the 267B(1) line using BioCoat Matrigel invasion chamber assay system. The present study has provided evidence that the v-Ki-ras oncogene may activate the nuclear target gene, ETS-1 gene, to mediate tumorigenic and metastatic capacity of the v-Ki-ras transformed prostate epithelial cells.

Musculoskeletal symptoms and neurological investigations in adrenocortical insufficiency: a case report and literature review

OBJECTIVES

Various forms of adrenocortical insufficiency can cause musculoskeletal symptoms such as muscle pain, tautness of the limbs, arthralgia, and flexion contractures. However, the findings of neurological investigations are inconclusive and have not been well summarized.

METHODS

We report the case of a 61-year-old man with isolated adrenocorticotropic hormone deficiency who presented with musculoskeletal symptoms, including flexion contractures. We performed three neurological investigations: nerve conduction studies, electromyography, and muscle biopsy analysis. Further, we reviewed reports of 16 patients with various forms of adrenocortical insufficiency and musculoskeletal symptoms by considering the findings of these three investigations.

RESULTS

From the literature review, we found that (a) analysis of muscle biopsy is the most sensitive technique, followed by electromyography and then nerve conduction studies; and (b) the longer the duration of the musculoskeletal symptoms, the greater the incidence of abnormal findings with all three techniques.

CONCLUSIONS

Physicians may prioritize neurological investigations, depending on these findings.

Isolation, identification and excretion profile of the principal urinary metabolite of the recently banned designer drug 1-(3-trifluoromethylphenyl)piperazine (TFMPP) in rats

The metabolism of 1-(3-trifluoromethylphenyl)piperazine (TFMPP), a recently banned designer drug, in rats was studied by analysing its urinary metabolites. p-Hydroxy-TFMPP (p-OH-TFMPP) was isolated and identified as the main metabolite by using nuclear magnetic resonance spectroscopy, gas chromatography-mass spectrometry and high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS). The time-course excretion profiles of TFMPP and p-OH-TFMPP in rats were investigated following a single intraperitoneal dosing of 5 mg kg(-1) TFMPP by using an optimized analytical procedure that combined solid-phase extraction and LC-ESI MS techniques. The cumulative amount of p-OH-TFMPP excreted within the first 48 h reached approximately 64% of the dose, of which 70% was the glucuronide conjugated form. The cumulative amount of parent TFMPP excreted was less than 0.7% of the dose. The results suggest that p-OH-TFMPP would be the most relevant metabolite to be detected for TFMPP exposure in the forensic and clinical analysis of human urine.

Oncogenic Ras upregulates NADPH oxidase 1 gene expression through MEK-ERK-dependent phosphorylation of GATA-6

Ras oncogene upregulates the expression of nicotinamide adenine dinucleotide phosphate oxidase (Nox) 1 via the Raf/MEK/ERK pathway, leading to the elevated production of reactive oxygen species that is essential for maintenance of Ras-transformation phenotypes. However, the precise transcriptional control mechanism underlying Ras-induced Nox1 expression remains to be elucidated. Here we demonstrated that via the MEK/ERK pathway, Ras signaling enhances the activity of the functional Nox1 promoter (nt -321 to -1) in colon cancer CaCo-2 cells and thereby induces the formation of the specific protein-DNA complexes in the two GATA-binding site-containing regions (nt -161 to -136 and -125 to -100). Supershift assays with GATA antibodies, protein analyses and chromatin immunoprecipitation revealed that GATA-6 is a component of the specific protein-DNA complexes at the Nox1 promoter. GATA-6 was able to trans-activate the Nox1 promoter but not a promoter in which the GATA-binding sites are mutated. Moreover, GATA-6 was phosphorylated at serine residues by MEK-activated ERK, which increased GATA-6 DNA binding, correlating with suppression of the Nox1 promoter activity by an MEK inhibitor PD98059. Finally, the site-directed mutation of the consensus ERK phosphorylation site (PYS(120)P to PYA(120)P) of GATA-6 abolished its trans-activation activity, suppressing of the growth of CaCo-2 cells. On the basis of these results, we propose that oncogenic Ras signaling upregulates the transcription of Nox1 through MEK-ERK-dependent phosphorylation of GATA-6.

[Case of pancreatic ascites successfully treated with endoscopic pancreatic drainage]

We report a 47-year-old man with abdominal distension without other distinct signs. Massive ascites with any singular lesions was revealed on computed tomography, and the ascites was high-amylase and high-protein. on these findings, pancreatic ascites was suspected and he was first treated with conservative therapy, but it failed. Computed tomography one month from the start of therapy demonstrated a pancreatic cyst, and endoscopic retrograde pancreatography revealed transudation of contrast medium from the cyst. A pancreatic duct stent was placed, and the ascites was smoothly eliminated. Endoscopic pancreatic stenting is considerable treatment for pancreatic ascites.

Metabolism of the recently encountered designer drug, methylone, in humans and rats

The urinary metabolites of methylone in humans and rats were investigated by analysing urine specimens from its abuser and after administrating to rats with gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS), using authentic standards. The time-course excretion profiles of methylone and its three metabolites in rats were further investigated after a single intraperitoneal dosing of 5 mg kg-1 methylone hydrochloride. Two major metabolic pathways were revealed for both humans and rats as follows: (1) side-chain degradation by N-demethylation to the corresponding primary amine methylenedioxycathinone (MDC), partly conjugated; and (2) demethylenation followed by O-methylation of either a 3- or 4-OH group on the benzene ring to produce 4-hydroxy-3-methoxymethcathinone (HMMC) or 3-hydroxy-4-methoxymethcathinone (3-OH-4-MeO-MC), respectively, mostly conjugated. Of these metabolites, HMMC was the most abundant in humans and rats. The cumulative amount of urinary HMMC excreted within the first 48 h in rats was approximately 26% of the dose, and the amount of the parent methylone was not more than 3%. These results demonstrate that the analysis of HMMC will be indispensable for proof of the use of methylone in forensic urinalysis.

[A case of granulocyte-colony stimulating factor producing gastric cancer]

We report a case of granulocyte-colony stimulating factor producing gastric cancer with multiple liver metastases. A 68-year-old woman who complained of epigastralgia visited our hospital. Upper gastrointestinal endoscopic examination revealed a type-2 gastric cancer. The laboratory data at admission indicated leukocytosis (35,900/microl) and a high level of serum granulocyte-colony stimulating factor (61 pg/mg). Granulocyte-colony stimulating factor producing gastric cancer was diagnosed by immunohistochemistry of biopsy specimen. Since we detected multiple liver metastases, chemotherapy was performed. Granulocyte-colony stimulating factor-producing gastric cancer is relatively rare and we summarize previous reports.

Inhibition of NADPH oxidase 4 activates apoptosis via the AKT/apoptosis signal-regulating kinase 1 pathway in pancreatic cancer PANC-1 cells

Pancreatic adenocarcinoma is an aggressive human malignancy and is characterized by resistance to apoptosis. Recently, NADPH oxidase (Nox) 4-mediated generation of intracellular reactive oxygen species (ROS) was proposed to confer antiapoptotic activity and thus a growth advantage to pancreatic cancer cells. The signaling mechanism by which Nox4 transmits cell survival signals remains unclear. Here, we show that both a flavoprotein inhibitor, diphenylene iodonium (DPI), and small interfering RNAs designed to target Nox4 mRNA (siNox4RNAs) inhibited superoxide production in PANC-1 pancreatic cancer cells, and depletion of ROS by DPI or siNox4RNAs induced apoptosis. Parallely, DPI treatment and siNox4RNA transfection blocked activation of the cell survival kinase AKT by attenuating phosphorylation of AKT. Furthermore, AKT phosphorylation of apoptosis signal-regulating kinase 1 (ASK1) on Ser-83 was reduced by DPI and siNox4RNAs. When ASK1Ser83Ala (an AKT phosphorylation-defective ASK1 mutant) was introduced into PANC-1 cells, this mutant alone induced apoptosis. But, addition of DPI or co-transfection of siNox4RNA had no additive effect, indicating that the mutant can substitute for these reagents in apoptosis induction. Taken together, these findings suggest that ROS generated by Nox4, at least in part, transmit cell survival signals through the AKT-ASK1 pathway in pancreatic cancer cells and their depletion leads to apoptosis.

Megakaryocytes derived from human embryonic stem cells: a genetically tractable system to study megakaryocytopoiesis and integrin function

BACKGROUND

The platelet fibrinogen receptor, a heterodimer consisting of integrin subunits alpha(IIb) and beta(3), is required for platelet aggregation, spreading, and hemostasis. Platelet agonists such as thrombin and adenosine diphosphate (ADP) lead to the activation of alpha(IIb)beta(3), thereby enhancing its affinity and avidity for binding fibrinogen (inside-out signaling). Furthermore, fibrinogen binding to alpha(IIb)beta(3) triggers cytoskeletal changes and granule release (outside-in signaling).

AIM

Genetic approaches to characterize the molecular pathways involved in alpha(IIb)beta(3) signaling are not possible with anucleate blood platelets. Therefore, we have established an OP9 stromal cell co-culture system to generate megakaryocytes from human embryonic stem cells (hESCs).

RESULTS

alpha(IIb)beta(3) activation, measured by soluble fibrinogen binding to hESC-derived megakaryocytes, /GPIbalpha(+) cells, is readily detectable following stimulation with known platelet agonists. Dose-response curves for peptide agonists specific for the two platelet thrombin receptors, protease-activated receptor 1 (PAR1) and PAR4, show a relative responsiveness that mirrors that of human platelets, and sub-maximal ADP responses are augmented by epinephrine. Moreover, hESC-derived megakaryocytes undergo lamellipodia formation, actin filament assembly, and vinculin localization at focal adhesions when plated on a fibrinogen-coated surface, characteristic of alpha(IIb)beta(3) outside-in signaling. Undifferentiated hESCs genetically modified by lentiviral infection can be cloned and maintained in an undifferentiated state and then differentiated into megakaryocytes capable of alpha(IIb)beta(3) activation.

CONCLUSION

Using hESCs, we have developed a renewable source of human megakaryocytes, and a genetically tractable system for studying megakaryocytopoiesis and alpha(IIb)beta(3) signaling in the native cellular environment.

[Examination of second-line therapies following administration of low-dose TS-1+CDDP for highly-advanced gastric cancer]

Sixteen patients with highly-advanced gastric cancer were administered low-dose TS-1 and CDDP as a first-line treatment, followed by either paclitaxel or CPT-11/CDDP as a second-line treatment. The results of the 2 second-line treatments are reported herein. Overall response rate for the first-line treatment was 55.6%. For the second-line treatments, responses were noted in both the paclitaxel group and the CPT-11/CDDP group. Overall MST was 16.3 months and 1-year survival was 60%. The paclitaxel group, however, showed significantly better prognoses than the CPT-11/CDDP group. Adverse reactions to the first-line treatment were grade 3 leukopenia in 1 patient, with no other reactions over grade 2 observed. No adverse reaction greater than grade 2 was noted during administration of the second-line treatments. These results appear to present ample data that a first-line treatment of low-dose TS-1/CDDP followed by a second-line treatment of paclitaxel at 1/week in the outpatient setting yields improved prognoses and minimal adverse reactions.

Complete response of Sister Mary Joseph Nodule from gastric adenocarcinoma treated with combination chemotherapy of low-dose S-1 and cisplatin

A case of an unresected, advanced gastric cancer with Sister Mary Joseph nodule was presented. It was treated with new combination chemotherapy of low-dose S-1 and cisplatin producing complete response of periumbilical metastasis. Few treatments are efficacious for umbilical invasion of peritoneal dissemination. A complete response for Sister Mary Joseph nodule from gastric adenocarcinoma has not been ever reported.

[A case of vulval extramammary Paget's disease associated with pancreatic cancer that was successfully treated with chemotherapy]

We report the case of an 84-year-old woman with vulval extramammary Paget's disease associated with pancreatic cancer who was successfully treated. At first, biweekly low-dose FP (cisplatin 10 mg/body, 5-fluorouracil 250 mg/body) was administered by intravenous infusion. Next, we attempted a regimen of gemcitabine (1,000 mg/body) was administered weekly by intravenous infusion. As a result, the size of the pruritic lesion of the vulva was reduced more than 50%, and the serum level of CA19-9 decreased clearly. These treatments would be a valid option in certain cases of pancreas cancer and extramammary Paget's disease.

Urinary excretion of selegiline N-oxide, a new indicator for selegiline administration in man

1. The metabolism of selegiline (SG) has been studied by investigating the time-course of urinary excretion of SG and its metabolites using high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS) in combination with solid-phase extraction. 2. The excretion profiles of SG and its four major metabolites, selegiline-N-oxide (SGO), N-desmethylselegiline (DM-SG), methamphetamine (MA) and amphetamine (AP), were investigated in six healthy volunteers after oral administrations of SG hydrochloride in a single dose of 2.5 or 7.5mg, and a repeat twice-daily dose of 5.0 mg day(-1) (for 3 days). 3. The cumulative amount of SGO excreted within approximately the first 8-12h was comparable with MA, and the amount in the first 72 h was 2.0-7.8 times larger (2.8-13.2% of the dose) than that of DM-SG. 4. These results demonstrate that SGO can be used in place of DM-SG, which is known to be a main specific metabolite of SG, as a new indicator for the discrimination of SG use compared with MA abuse.

Effect of Seihai-to, a Kampo medicine, in relapsing aspiration pneumonia--an open-label pilot study

Two published case reports described palliation of disease after Seihai-to therapy for refractory aspiration pneumonia caused by recurrent laryngeal nerve paralysis and cerebrovascular disease. We undertook an open-label trial in patients with relapsing aspiration pneumonia. Fifteen patients with relapsing aspiration pneumonia were randomly divided into conventional therapy group (n = 8) or Seihai-to group (n = 7). In Seihai-to group, patients were treated with Seihai-to in addition to conventional therapy (Western medicines). Frequency of feverish days and antibiotics-use, CRP value and chest CT or X-ray findings were compared between the two groups during the study period of 16 weeks. In the Seihai-to group, the latency of swallowing reflex was measured in 6 patients before and after administration of Seihai-to. The mean values of fever index, CRP value and antibiotics-use in the Seihai-to group were decreased significantly, compared with those of the conventional therapy group. However, the latency of the swallowing reflex after 4 weeks of treatment was not significantly changed (p = 0.249), compared with the latency before administration of Seihai-to. No adverse reaction was observed in either group. Seihai-to was effective in reducing relapse of aspiration pneumonia in this small group. Seihai-to might not improve the swallowing reflex, but might instead improve a defense mechanism or excessive inflammation caused by pneumonia in the lower airway. Further evaluation of Seihai-to therapy for patients with aspiration pneumonia in a larger population is warranted.

Altered cultured mesangial cell phenotypes from RF/J mice: a spontaneous immune complex mediated glomerulonephritis with progressive glomerulosclerosis

BACKGROUND/AIM

RF/J mice are a model of spontaneous immune complex mediated glomerulonephritis showing massive extracellular matrix accumulation and progressive glomerulosclerosis. The aim of this study was to investigate whether there is an altered cultured mesangial cell (MC) phenotype in RF/J mice associated with these glomerular changes.

METHODS

The nature of cultured MCs from RF/J mice in the proliferative response to platelet-derived growth factor (PDGF) BB was compared with that of normal mice (BALB/c) by 3H-thymidine incorporation. The binding of PDGF-BB was examined with Scatchard analysis, and the messenger RNAs (mRNAs) of PDGF beta-receptor, collagen I, collagen IV, and fibronectin were detected using Northern blot analysis in the MCs of each mouse.

RESULTS

The 3H-thymidine incorporation of MCs from RF/J mice showed significantly lower responses to PDGF-BB stimulations with concentrations ranging from 0.5 to 10.0 ng/ml in comparison with those of BALB/c mice which exhibited a proportional dose- dependent increase of the incorporation (p < 0.05 for 0.5 ng/ml PDGF-BB, p < 0.01 for 1.0-10.0 ng/ml). According to the Scatchard analysis, MCs from BALB/c mice showed aKD of 105 pM of PDGF-BB binding to its receptors, and the density of receptors was 5.82 fmol/10(5) cells. However, no binding PDGF-BB site on the surface of MCs from RF/J mice was noted. Northern blot analysis of MCs from RF/J mice indicated negative expression of detectable PDGF-beta receptor mRNA. As for matrix protein messages, MCs from RF/J mice did not express mRNA of type I collagen, but did express a higher amount of type IV collagen and fibronectin in comparison with MCs from normal BALB/c mice.

CONCLUSIONS

An altered phenotype in MCs of RF/J mice was demonstrated, possibly contributing to the characteristic pathological glomerular changes. However, the precise association remains to be clarified.

The Sos1-Rac1 signaling. Possible involvement of a vacuolar H(+)-ATPase E subunit

We have purified and identified a 32-kDa protein interacting with the Dbl oncogene homology domain of mSos1(Sos-DH) from rat brains by glutathione S-transferase-Sos-DH affinity chromatography. Peptide sequencing revealed that the protein is identical to a positive regulatory E subunit (V-ATPase E) of a vacuolar H(+)-ATPase, which is responsible for acidification of endosome and alkalinization of intracellular pH. The interaction between V-ATPase E and Sos-DH was confirmed by yeast two-hybrid assay. A coimmunoprecipitation assay demonstrated that a V-ATPase E protein physiologically bound to mSos1, and the protein was colocalized with mSos1 in the cytoplasm, as determined by immunohistochemistry. mSos1 was found in the early endosome fraction together with V-ATPase E and Rac1, suggesting the functional involvement of mSos1/V-ATPase E complexes in the Rac1 activity at endosomes. Overexpression of V-ATPase E in COS cells enhanced the ability of mSos1 to promote the guanine nucleotide exchange activity for Rac1 and stimulated the kinase activity of Jun kinase, a downstream target of Rac1. Thus, the data indicate that V-ATPase E may participate in the regulation of the mSos1-dependent Rac1 signaling pathway involved in growth factor receptor-mediated cell growth control.

Immunohistochemical diagnosis of Cryptococcus neoformans var. gattii infection in chronic meningoencephalitis: the first case in Japan

Cryptococcus neoformans (C. neoformans) var. gattii infection usually occurs in tropical and subtropical areas, and rarely in the northern hemisphere. We report the first Japanese with cryptococcal meningoencephalitis caused by C. neoformans var. gattii infection that occurred during a trip to Australia. This agent was identified in a cerebellar biopsy specimen by immunohistochemical technique with serotype-specific anti-sera. Because the meningitis caused by it did not respond well to conventional therapy, we used an aggressive therapeutic regimen to successfully treat the patient. Even in areas where C. neoformans var. gattii does not exist, this infection should be considered possible as a travel-related infection.

Biphasic alterations in gastrointestinal transit following endotoxaemia in mice

Lipopolysaccharide (LPS)-induced alterations of gastrointestinal transit were studied in mice using activated charcoal. LPS (10 mg kg-1) induced biphasic alterations of intestinal transit. Increase (acceleration phase) and delay (lag phase) in gastrointestinal transit were observed at 90 and 480 min after LPS injection, respectively. LPS administration induced significant increases in tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and nitrate levels in blood serum with maximal levels observed at 1.5, 4, and 8 h after LPS administration, respectively. The effects of recombinant human lzactoferrin (rhLF) on LPS- induced alteration of gastrointestinal transit, and production of TNF-alpha, IL-1beta and nitrate were also studied. Animals were pretreated with rhLF 24 hours before intraperitoneal administration of LPS. RhLF significantly increased gastrointestinal transit during the lag phase. In addition, rhLF decreased the level of TNF-alpha in endotoxaemic animals. The levels of IL-1beta and nitrate were not significantly changed by rhLF. In conclusion, the effect of LPS on gastrointestinal transit is biphasic and the mechanism controlling the second phase most likely depends on TNF-alpha production, while the first phase most likely does not depend on TNF-alpha. On the other hand, it may be regulated by IL-1beta and nitric oxide production.

Platelet integrin alphaIIbbeta3-ligand interactions: what can we learn from the structure?

Upon vascular injury, platelets initiate interaction with exposed subendothelial matrices through various receptors such as glycoprotein (GP) Ib/IX/V complex, alpha2beta1 integrin, and GPVI/FcRgamma. Although these interactions cannot sustain stable platelet thrombus formation by themselves, they ultimately lead to the activation of alphaIIbbeta3 integrin (GPIIb-IIIa complex [GPIIb-IIIa]), the most abundant receptor in platelets. The alphaIIbbeta3 integrin plays a central role in primary hemostasis by serving as a receptor for fibrinogen and von Willebrand factor (vWf). It establishes a stable interaction with vWf bound to the extracellular matrices and uses fibrinogen as a bridging molecule in platelet aggregate formation. The alphaIIbbeta3 integrin also plays an important role in the pathogenesis of thrombosis. Over the past decades, a tremendous amount of effort has been made to elucidate the ligand-binding mechanisms of alphaIIbbeta3, in part because of its clinical significance. Most of the studies have relied on biochemical analyses of purified alphaIIbbeta3 or recombinant proteins generated in vitro. With the lack of actual 3-dimensional structure, molecular modeling has provided a useful framework for interpreting such experimental data on structure-function correlation of integrin molecules. However, it has also generated disagreement between different models. The aim of this minireview is to summarize the past efforts as well as the recent accomplishments in elucidating the structure/function of alphaIIbbeta3. Finally, we will try to explain all those experimental data using the recently published crystal structure of the extracellular domains of the alphaVbeta3 heterodimeric complex.

Amino acid residues in the alpha IIb subunit that are critical for ligand binding to integrin alpha IIbbeta 3 are clustered in the beta-propeller model

Several distinct regions of the integrin alpha(IIb) subunit have been implicated in ligand binding. To localize the ligand binding sites in alpha(IIb), we swapped all 27 predicted loops with the corresponding sequences of alpha(4) or alpha(5). 19 of the 27 swapping mutations had no effect on binding to both fibrinogen and ligand-mimetic antibodies (e.g. LJ-CP3), suggesting that these regions do not contain major ligand binding sites. In contrast, swapping the remaining 8 predicted loops completely blocked ligand binding. Ala scanning mutagenesis of these critical predicted loops identified more than 30 discontinuous residues in repeats 2-4 and at the boundary between repeats 4 and 5 as critical for ligand binding. Interestingly, these residues are clustered in the predicted beta-propeller model, consistent with this model. Most of the critical residues are located at the edge of the upper face of the propeller, and several critical residues are located on the side of the propeller domain. None of the predicted loops in repeats 1, 6, and 7, and none of the four putative Ca(2+)-binding predicted loops on the lower surface of the beta-propeller were important for ligand binding. The results map an important ligand binding interface at the edge of the top and on the side of the beta-propeller toroid, centering on repeat 3.

[A pilot study of low-dose TS-1 and cisplatin combination chemotherapy for advanced gastric cancer]

TS-1, a novel oral formation of 5-fluorouracil, consists of tegafur (5-FU), CDHP and Oxo. Low-dose cisplatin (CDDP) and TS-1 was evaluated in 12 patients with advanced or recurrent gastric cancer. CDDP was given biweekly at a dose of 15 mg/m2 infused for 30 minutes, and 80 mg/body of TS-1 was orally administered as many times as possible. The response rate was 41.7%. Median survival time was 13.3 months. In one case, an adverse reaction of grade 3 leucopenia was observed. Thus, thought it is necessary to watch for leucopenia, this chemotherapy could well be effective for patients with advanced or recurrent gastric cancer.