p53AIP1 expression can be a prognostic marker in non-small cell lung cancer

AIMS

p53AIP1 is a potential mediator of p53-dependent apoptosis that is mutated in many kinds of carcinoma. To investigate the role of this gene for non-small cell lung cancer, we compared the relationship between p53AIP1 gene expression and clinicopathological status of lung cancer.

MATERIALS AND METHODS

Seventy samples from non-small cell lung cancer patients were obtained between 1997 and 2003. For quantitative evaluation of RNA expression by polymerase chain reaction (PCR) we used the Taqman PCR methods. Exons 5-8 of the p53 gene were analysed using PCR-single-stranded conformation polymorphism and sequenced for mutation analysis.

RESULTS

p53AIP1 gene expression levels in the lymph node metastasis-positive group were significantly lower than in the negative group (positive 35.1+/-83.9; negative 64.2+/-113.4; P=0.0486). The overall survival of the p53AIP1 low expression group was significantly worse than that of the p53AIP1 high expression group (P=0.0206). In the multivariate Cox proportional hazard model, p53AIP1 (P=0.0489) was the independent predictor for overall survival. When we investigated mutation analyses of the p53 gene, we could find several point mutations in 15.7% of all samples. However, there was no relationship between p53AIP1 expression and p53 status.

CONCLUSIONS

These data suggest that the p53AIP1 gene is important for non-small cell lung cancer progression and may be a possible prognostic marker.

[Intrapulmonary sequestration operated by video-assisted thoracoscopic surgery lobectomy; report of a case]

Pulmonary sequestration is a rare malformation of the respiratory tract. We here report an adult case of intralobar pulmonary sequestration with aberrant artery of the right lower lobe. A 20-year-old man admitted to our hospital with a chest discomfort. Chest computed tomography (CT), angiography, and scintigraphy showed abnormal findings of the right lower lobe with an aberrant artery. Under the diagnosis of pulmonary sequestration, video-assisted thoracoscopic surgery (VATS) lobectomy was performed. VATS is useful for the operation of pulmonary sequestration.

Hyperplasia and carcinomas in Pten-deficient mice and reduced PTEN protein in human bladder cancer patients

PTEN is a tumor suppressor gene mutated in many human cancers. We used the Cre-loxP system to generate an urothelium-specific null mutation of Pten in mice [FabpCrePten(flox/flox) (FPten(flox/flox)) mice]. Histologic examination revealed that all FPten(flox/flox) mice exhibited urothelial hyperplasia in which component cells showed enlarged nuclei and increased cell size. With time, 10% of FPten(flox/flox) mice spontaneously developed pedicellate papillary transitional cell carcinomas (TCC). This type of tumor also arose in FPten(flox/flox) mice treated with the chemical carcinogen N-butyl-N-(4-hydroxybutyl) nitrosamine. FPten(flox/flox) urothelial cells were hyperproliferative and showed increased activation of the survival signaling molecules Akt and extracellular signal-regulated kinase. In humans, 53% of primary bladder cancer patients exhibited decreased or absent expression of PTEN protein in either the cytoplasm or nucleus of tumor cells. In early bladder cancers, PTEN expression was repressed in 42% of superficial papillary TCC but in only 8% of cases of carcinoma in situ (CIS). In advanced bladder cancers, PTEN protein was significantly reduced (particularly in the nucleus) in 94% of cases, and this decrease in PTEN correlated with disease stage and grade. Thus, PTEN deficiency may contribute to bladder cancer both by initiating superficial papillary TCC and by promoting the progression of CIS to advanced invasive and metastatic forms.

Changes in the fluctuation of the contraction rhythm of spontaneously beating cardiac myocytes in cultures with and without cardiac fibroblasts

The heart functions as a syncytium of cardiac myocytes and surrounding supportive non-myocytes such as fibroblasts. There is a possibility that a variety of non-myocyte-derived factors affect the maturation of cardiac myocytes in the development of the heart. Cultured neonatal cardiac myocytes contract spontaneously and cyclically. The fluctuation of beating rhythm varies depending on the strength of coupling through gap junctions among cardiac myocytes, indicating that the development of intercellular communication via gap junctions is crucial to the stability of contraction rhythm in cardiac myocytes. In this study, we aimed at elucidating whether and how cardiac fibroblasts affect the development of cardiac myocytes from the point of view of the changes in the fluctuation of the contraction rhythm of cardiac myocytes in cardiac myocyte-fibroblast co-cultures. The present study suggested that cardiac fibroblasts co-cultured with cardiac myocytes enhanced the intercellular communication among myocytes via gap junctions, thereby stabilizing the spontaneous contraction rhythm of cultured cardiac myocytes.

A simple protocol for preventing falls and fractures in elderly individuals with musculoskeletal disease

Our protocol resulted in a significant prevention of falls and fractures in addition to marked improvements in the balance function. Intervention comprised a new balance exercise and quadriceps femoris exercise. Subjects were outpatients aged >or=65 years old with musculoskeletal disorders who had a result of <or=15 s for the timed one-leg balance test.

INTRODUCTION

A study on chronological changes in the level of required care revealed that the level of care increases markedly for older patients requiring non-intensive or intensive long-term care. The aim of the present study was to identify frail elderly patients among older patients with chronic pain of the musculoskeletal system and to assess the fracture prevention and fall prevention effects of exercise therapy using stratified analysis.

METHODS

This was a prospective cohort study consisting of 683 outpatients with chronic pain of the musculoskeletal system who were >or=65 years old and had a result of <or=15 s for the timed one-leg balance test with eyes open. Intervention consisted of a new balance exercise and quadriceps femoris exercise regimen. The main outcome was fall rate, while secondary outcomes were the results of the timed one-leg balance test with eyes open and fracture rate.

RESULTS

Fall rate was decreased by 44% (p < 0.001) and fracture rate by 47% (p < 0.05) by 8 months after the start of the intervention. The results of the timed one-leg balance testing with eyes open improved two- to threefold after intervention (p < 0.01).

CONCLUSIONS

Our protocol has been safely implemented at a large number of clinics in Japan, and the reductions in frequency of falls and fractures suggest that it provides effective preventive care.

Changes in the spontaneous calcium oscillations for the development of the preconditioning-induced ischemic tolerance in neuron/astrocyte co-culture

Spontaneous Ca(2+) oscillations are believed to contribute to the regulation of gene expression. Here we investigated whether and how the dynamics of Ca(2+) oscillations changed after sublethal preconditioning (PC) for PC-induced ischemic tolerance in neuron/astrocyte co-cultures. The frequency of spontaneous Ca(2+) oscillations significantly decreased between 4 and 8 h after the end of PC in both neurons and astrocytes. Treatment with 2-APB, an inhibitor of IP3 receptors, decreased the oscillatory frequency, induced ischemic tolerance and a down-regulation of glutamate transporter GLT-1 contributing to the increase in the extracellular glutamate during ischemia. The expression of GLT-1 is known to be up-regulated by PACAP. Treatment with PACAP38 increased the oscillatory frequency, and antagonized both the PC-induced down-regulation of GLT-1 and ischemic tolerance. These results suggested that the PC suppressed the spontaneous Ca(2+) oscillations regulating the gene expressions of various proteins, especially of astrocytic GLT-1, for the development of the PC-induced ischemic tolerance.

High-mobility group box 1 protein promotes development of microvascular thrombosis in rats

BACKGROUND

Sepsis is a life-threatening disorder resulting from systemic inflammatory and coagulatory responses to infection. High-mobility group box 1 protein (HMGB1), an abundant intranuclear protein, was recently identified as a potent lethal mediator of sepsis. However, the precise mechanisms by which HMGB1 exerts its lethal effects in sepsis have yet to be confirmed. We recently reported that plasma HMGB1 levels correlated with disseminated intravascular coagulation (DIC) score, indicating that HMGB1 might play an important role in the pathogenesis of DIC.

OBJECTIVES

To investigate the mechanisms responsible for the lethal effects of HMGB1, and more specifically, to explore the effects of HMGB1 on the coagulation system.

METHODS

Rats were exposed to thrombin with or without HMGB1, and a survival analysis, pathologic analyses and blood tests were conducted. The effects of HMGB1 on the coagulation cascade, anticoagulant pathways and surface expression of procoagulant or anticoagulant molecules were examined in vitro.

RESULTS

Compared to thrombin alone, combined administration of thrombin and HMGB1 resulted in excessive fibrin deposition in glomeruli, prolonged plasma clotting times, and increased mortality. In vitro, HMGB1 did not affect clotting times, but inhibited the anticoagulant protein C pathway mediated by the thrombin-thrombomodulin complex, and stimulated tissue factor expression on monocytes.

CONCLUSIONS

These findings demonstrate the procoagulant role of HMGB1 in vivo and in vitro. During sepsis, massive accumulation of HMGB1 in the systemic circulation would promote the development of DIC.

[Bronchial lipoma treated by surgical resection; report of a case]

We report a case of bronchial lipoma, which relapsed after endoscopic treatment, and was treated by surgical resection. An abnormal shadow on chest X-ray was noted at the annual medical checkup of a 44-year-old man. Chest computed tomography (CT) demonstrated a tumor in the right basal bronchus and linear opacity on the peripheral side of that tumor. Bronchoscopic examination demonstrated a smooth polipoid tumor occluding the right basal lobe bronchus. Bronchoscopic biopsy specimens were not sufficient for histological diagnosis. We performed endobronchial resection of the tumor using electrosurgical snare, but 2 months after endoscopic treatment, the tumor relapsed. We therefore performed right S(9+10) segmentectomy. The tumor was 11 x 9mm in size and the histological diagnosis was an endobronchial lipoma. More than 4 years after resection, the patient is alive without recurrence.

Expression of ATP sensitive K+ channel subunit Kir6.1 in rat kidney

ATP-sensitive K+ (K(ATP)) channels in kidney are considered to play roles in regulating membrane potential during the change in intracellular ATP concentration. They are composed of channel subunits (Kir6.1, Kir6.2), which are members of the inwardly rectifying K+ channel family, and sulphonylurea receptors (SUR1, SUR2A and SUR2B), which belong to the ATP-binding cassette superfamily. In the present study, we have investigated the expression and localization of Kir6.1 in rat kidney with Western blot analysis, immunohistochemistry, in situ hybridization histochemistry, and immunoelectron microscopy. Western blot analysis showed that Kir6.1 was expressed in the mitochondria and microsome fractions of rat kidney and very weakly in the membrane fractions. Immunohistochemistry revealed that Kir6.1 was widely distributed in renal tubular epithelial cells, glomerular mesangial cells, and smooth muscles of blood vessels. In immunoelectron microscopy, Kir6.1 is mainly localized in the mitochondria, endoplasmic reticulum (ER), and very weakly in cell membranes. Thus, Kir6.1 is contained in the kidney and may be a candidate of mitochondrial K(ATP) channels.

The Pten/PI3K pathway governs the homeostasis of Valpha14iNKT cells

The tumor suppressor PTEN is mutated in many human cancers. We previously used the Cre-loxP system to generate mice (LckCrePten mice) with a Pten mutation in T-lineage cells. Here we describe the phenotype of Pten-deficient Valpha14iNKT cells. A failure in the development of Valpha14iNKT cells occurs in the LckCrePten thymus between stage 2 (CD44(high)NK1.1(-)) and stage 3 (CD44(high)NK1.1(+)), resulting in decreased numbers of peripheral Valpha14iNKT cells. In vitro, Pten-deficient Valpha14iNKT cells show reduced proliferation and cytokine secretion in response to alphaGalCer stimulation but enhanced inhibitory Ly49 receptor expression. Following interaction with dendritic cells (DCs) loaded with alphaGalCer, Pten-deficient Valpha14iNKT cells demonstrate activation of PI3K. Indeed, the effects of the Pten mutation require intact function of the PI3K subunits p110gamma and p110delta. In vivo, LckCrePten mice display reduced serum IFNgamma after alphaGalCer administration. Importantly, Valpha14iNKT cell-mediated protection against the metastasis of melanoma cells to the lung was impaired in the absence of Pten. Thus, the Pten/PI3K pathway is indispensable for the homeostasis and antitumor surveillance function of Valpha14iNKT cells.

Glutamate release from astrocytes is stimulated via the appearance of exocytosis during cyclic AMP-induced morphologic changes

Recent studies have shown that astrocytes release various transmitters including glutamate and thus directly affect synaptic neurotransmission. The mechanisms involved in the release of glutamate from astrocytes remain unclear, however. In the present study, we examined differences in 1) the amount of glutamate released, 2) the appearance of exocytosis, and 3) the expression of SNARE (soluble N-ethylmaleimide sensitive fusion protein attachment protein receptor) proteins between cyclic AMP-treated and non-treated astrocytes in culture. Extracellular glutamate was detected in the recording solution of cyclic AMP-treated astrocytes after stimulation with ATP by high-performance liquid chromatography and NADH imaging. Exocytosis, which was observed by FM1-43 imaging, appeared in cyclic AMP-treated astrocytes in a punctiform fashion, but not in non-treated cells, after stimulation with ATP and glutamate. Immunocytochemistry and Western blotting showed that the amount of SNARE proteins increased during cAMP-induced morphologic changes, and in particular, a v-SNARE, synaptobrevin, appeared as punctiform staining in the cytosol of cyclic AMP-treated astrocytes. These findings show that astrocytes acquire SNARE proteins during cyclic AMP-induced differentiation, and suggest that glutamate is released by exocytosis in cyclic AMP-treated astrocytes in response to ATP released from neighboring neurons and astrocytes.

Possible involvement of ATP-purinoceptor signalling in the intercellular synchronization of intracellular Ca2+ oscillation in cultured cardiac myocytes

Isolated and cultured neonatal cardiac myocytes contract spontaneously and cyclically. The contraction rhythms of two isolated cardiac myocytes, each of which beats at different frequencies at first, become synchronized after the establishment of mutual contacts, suggesting that mutual entrainment occurs due to electrical and/or mechanical interactions between two myocytes. The intracellular concentration of free Ca(2+) also changes rhythmically in association with the rhythmic contraction of myocytes (Ca(2+) oscillation), and such a Ca(2+) oscillation was also synchronized among cultured cardiac myocytes. In this study, we investigated whether intercellular communication other than via gap junctions was involved in the intercellular synchronization of intracellular Ca(2+) oscillation in spontaneously beating cultured cardiac myocytes. Treatment with either blockers of gap junction channels or an un-coupler of E-C coupling did not affect the intercellular synchronization of Ca(2+) oscillation. In contrast, treatment with a blocker of P2 purinoceptors resulted in the asynchronization of Ca(2+) oscillatory rhythms among cardiac myocytes. The present study suggested that the extracellular ATP-purinoceptor system was responsible for the intercellular synchronization of Ca(2+) oscillation among cardiac myocytes.

Changes in cardiovascular function on treatment of inhibitors of apoptotic signal transduction pathways in left ventricular remodeling after myocardial infarction

INTRODUCTION

It has been suggested that apoptosis in cardiac remodeling after myocardial infarction (MI) occurs in cardiomyocytes and is critically involved in the process of postinfarct cardiac remodeling. We investigated the pathophysiological link between myocardial apoptosis and cardiovascular function by modulating apoptotic signal transduction pathways.

METHODS

Either a caspase-3 inhibitor (CasI) or a calpain inhibitor (CalI) was administered immediately after MI in a rat model of MI. Blood pressure (BP), heart rate (HR), and blood flow velocity (BFV) were measured, and pressure-rate product (PRP) was calculated to estimate the changes in cardiovascular function (n=6 for each group).

RESULTS

BFV showed no remarkable changes in any of the groups. Both systolic blood pressure (SBP) and HR changed significantly (P<.01) in the MI+CasI and MI+CalI groups at 1 day after MI and returned to control levels thereafter. In contrast, SBP and HR remained significantly (P<.01) altered in the MI group. PRP in the MI groups was significantly decreased (P<.05 in the MI and MI+CasI groups; P<.01 in the MI+CalI group) at 1 day after MI and returned to control levels at 4 days.

CONCLUSION

This study suggests that inhibition of apoptosis during left ventricular remodeling ameliorates cardiovascular function in remodeled hearts.

Nitric oxide produced during sublethal ischemia is crucial for the preconditioning-induced down-regulation of glutamate transporter GLT-1 in neuron/astrocyte co-cultures

In the brain, prior sublethal ischemia (preconditioning, PC) produces tolerance of neurons to subsequent lethal ischemia. This study aims at elucidating whether and how nitric oxide (NO) produced during PC is involved in the PC-induced ischemic tolerance of neurons in neuron/astrocyte co-cultures. The rise in the extracellular concentration of glutamate during ischemia caused by the reversed uptake of glutamate (Glu) by the astrocytic Glu transporter GLT-1 was markedly suppressed by the prior PC treatment, but the suppression was reversed by treatment with an inhibitor of nitric oxide synthase (NOS) during PC. Immunocytochemical and Western blot analyses demonstrated that the expression of GLT-1 was down-regulated after the PC insult, and this down-regulation was also antagonized by treatment with NOS inhibitors during PC. Here we show that nNOS-derived NO produced during PC was crucial for the down-regulation of astrocytic GLT-1, and this down-regulation coincided with an increased survival rate of neurons.

Reversed Actrocytic GLT-1 during Ischemia is Crucial to Excitotoxic Death of Neurons, but Contributes to the Survival of Astrocytes themselves

During ischemia, the operation of astrocytic/neuronal glutamate transporters is reversed and glutamate and Na(+) are co-transported to the extracellular space. This study aims to investigate whether this reversed operation of glutamate transporters has any functional meanings for astrocytes themselves. Oxygen/glucose deprivation (OGD) of neuron/astrocyte co-cultures resulted in the massive death of neurons, and the cell death was significantly reduced by treatment with either AP5 or DHK. In cultured astrocytes with little GLT-1 expression, OGD produced Na(+) overload, resulting in the reversal of astrocytic Na(+)/Ca(2+)-exchanger (NCX). The reversed NCX then caused Ca(2+) overload leading to the damage of astrocytes. In contrast, the OGD-induced Na(+) overload and astrocytic damage were significantly attenuated in PACAP-treated astrocytes with increased GLT-1 expression, and the attenuation was antagonized by treatment with DHK. These results suggested that the OGD-induced reversal of GLT-1 contributed to the survival of astrocytes themselves by releasing Na(+) with glutamate via reversed GLT-1.

Early and late gastric cancer arising in the remnant stomach after distal gastrectomy

AIM

Following distal gastrectomy, carcinogenesis has been suggested to result from gastroduodenal reflux. In this study, surgical cases of gastric cancer arising after distal gastrectomy were analyzed clinico-pathologically and the possible link to reflux examined.

PATIENTS

Thirty-two patients (24 males, 8 females; mean age, 68.7 years; age range, 33-84 years) with gastric cancer arising in the remnant stomach after gastrectomy (also known as gastric stump cancer) were included in this study. Patients were divided into two groups on the basis of the initial diagnosis (benign or malignant) prompting surgery, and distal gastrectomy reconstruction method (Billroth I or II).

RESULTS

The interval between distal gastrectomy and detection of cancer in the remnant stomach of patients treated initially for a benign gastric condition vs. malignancy was 360+/-33.04 and 63+/-19.16 months (median+/-SE), respectively (p<0.0001). However, the benign and malignant groups did not differ significantly in the clinicopathological analysis of their stump cancers. All 10 patients in whom gastric cancer was diagnosed within five years of initial surgery had initially been surgically treated for malignancy. The interval between surgery and detection of gastric cancer in the Billroth I and Billroth II groups was 84+/-26.67 and 276+/-44.26 months (median+/-SE), respectively (p<0.01). In the remnant stomach, cancer tended to occur near the site of gastrojejunostomy in the Billroth II group (p=0.05). Helicobacter pylori infection was only detected histologically in four patients who had undergone Billroth I reconstructions after distal gastrectomy for malignancy.

CONCLUSION

After distal gastrectomy, careful periodic endoscopic examination for microcarcinoma is required in patients, particularly in those who undergo surgery for malignancy, to maximize detection of gastric cancer.

[Spontaneous pneumomediastinum]

We encountered 3 patients with spontaneous pneumomediastinum. The patients were a 14-year-old female, a 16-year-old male and an 18-year-old male. All 3 were previously healthy. They complained of chest pain or dyspnea. On admission, physical examination revealed subcutaneous emphysema. Chest computed tomography (CT) revealed pneumomediastinum and subcutaneous emphysema. All patients were treated with rest and all recovered in 7 to 9 days without any complication. Spontaneous pneumomediastinum is an uncommon, usually benign, self-limited disorder that usually occurs in young adults without any apparent precipitating factor or disease. Most patients require only conservative treatment.

Granulocyte and Monocyte Adsorption Apheresis (GCAP) for Refractory Skin Diseases Caused by Activated Neutrophils and Psoriatic Arthritis: Evidence that GCAP Removes Mac-1-Expressing Neutrophils

In the present study, we have shown that granulocyte and monocyte adsorption apheresis (GCAP), an extracorporeal apheresis instrument whose column contains cellulose acetate (CA) beads, is useful for skin diseases attributable to activated granulocytes and psoriatic arthritis (PsA). We assessed the clinical effectiveness of GCAP and investigated the mechanisms underlying the adsorption of pathogenic granulocytes. The effect of GCAP was assessed in 14 patients with neutrophilic dermatoses and 16 with PsA. The mechanisms by which the instrument adsorbs activated granulocytes were investigated using an in vitro mini-column system that mimics the GCAP. Skin lesions and arthropathy improved in 22 of 29 patients (75.9%) and 14 of 18 (77.8%), respectively. Mac-1 (CD11b/CD18) expression on the peripheral neutrophils, increased compared with normal subjects, was reduced by GCAP. In the mini-column system, CA beads adsorbed 50% neutrophils; and adsorption was inhibited significantly by treating plasma with EDTA and blood cells with antihuman CD11b monoclonal antibody. GCAP was useful for treating neutrophilic dermatoses and PsA. GCAP adsorbs Mac-1-expressing neutrophils to the CA beads by the binding of complement component (iC3b) on CA beads and CD11b expressed on activated neutrophils.

Granulocyte and Monocyte Adsorption Apheresis for Cutaneous Allergic Vasculitis

Cutaneous allergic vasculitis (CAV) is characterized clinically by purpuric patches with secondary ulcerations, and histologically by leukocytoclastic vasculitis with neutrophil infiltrates. Granulocyte and monocyte adsorption apheresis (GCAP) is an extracorporeal apheresis instrument using a column containing cellulose acetate beads designed to remove pathogenic granulocytes. Here we report our assessment of the efficacy of GCAP for recurrent leg ulcers in a 49-year-old woman with CAV. She underwent five GCAP treatments at one-week intervals. In each treatment session, 1800 mL of blood was processed. Her leg ulcers responded well and her white blood cell and neutrophil counts and the expression level of CD11b/CD18, a marker for activated neutrophils, on her peripheral neutrophils were reduced from 7500/microL to 6500/microL, 4350/microL to 3315/microL, and 64.9 MFI (mean fluorescence intensity) to 27.0 MFI (normal controls: 10.5 +/- 1.2 MFI) by GCAP, respectively. These results suggest that GCAP is useful for skin disorders with leucocytoclastic vasculitis.