[Surgical approaches for superior sulcus tumor]

Surgical approach is one of the most crucial aspects in the treatment of superior sulcus tumor (SST). Posterior approach as described by Paulson and coworkers is appropriate for the resection of SST invading posterior part of the 1st rib and the vertebrae, whereas anterior approaches as described by Masaoka, Dartevelle, Grunenwald, or Rusca are suitable for resection of SST involving subclavian vessels. We present 2 cases of SST who underwent complete resection through the posterior approach and a modified hemi-clamshell approach, respectively. We also discuss the surgical approaches for SST with referring to literatures.

Calcium, vitamin D and dairy intake in relation to type 2 diabetes risk in a Japanese cohort

AIMS/HYPOTHESIS

Calcium and vitamin D have been implicated in the development of type 2 diabetes, but epidemiological evidence is limited. We examined prospectively the relation of calcium and vitamin D intake to type 2 diabetes risk in a Japanese cohort.

METHODS

Participants were 59,796 middle-aged and older men and women, who participated in the Japan Public Health Center-based Prospective Study and had no history of type 2 diabetes or other serious diseases. Dietary intake of calcium and vitamin D were estimated using a validated food frequency questionnaire. Logistic regression was used to assess the association between intake of these nutrients and self-reported newly diagnosed type 2 diabetes.

RESULTS

During a 5 year follow-up, 1,114 cases of type 2 diabetes were documented. Overall, calcium intake was not associated with a significantly lower risk of type 2 diabetes; the multivariable odds ratio for the highest vs lowest quartiles was 0.93 (95% CI 0.71-1.22) in men and 0.76 (95% CI 0.56-1.03) in women. However, among participants with a higher vitamin D intake, calcium intake was inversely associated with diabetes risk; the odds ratio for the highest vs lowest intake categories was 0.62 (95% CI 0.41-0.94) in men and 0.59 (95% CI 0.38-0.91) in women. Dairy food intake was significantly associated with a lower risk of type 2 diabetes in women only.

CONCLUSIONS/INTERPRETATION

Calcium and vitamin D may not be independently associated with type 2 diabetes risk. Our finding suggesting a joint action of these nutrients against type 2 diabetes warrants further investigation.

The role of immune cells in brain metastasis of lung cancer cells and neuron-tumor cell interaction

Following any type of brain injury such as lesion, stroke, and tumor/cancer invasion, microglia are rapidly activated and recruited to the site of injury. Microglia is the main immune effector cell population of the central nervous system and control immune cell recruitment. However, the molecular mechanism of brain metastasis and interaction between neuron-glia-tumor cells are poorly understood. Therefore, we established an animal model for brain metastasis using human lung cancer-derived cells (HARA-B) in nude mice. Accumulation of activated microglia was observed around tumor cells depending on the size of metastatic foci and the area of the brain. In vitro study, conditioned medium from primary cultured mouse microglia inhibited the proliferation of tumor cells, while tumor cell-conditioned medium inhibited the proliferation of primary cultured neurons from mouse cortex. Though the responsible factors released from microglia and tumor cells are still under investigation, these studies will contribute to understand the mechanism of cell-cell interaction in the brain and possible therapeutic target for brain metastasis.

Combinatory effects of androgen receptor deficiency and hind limb unloading on bone

Male sex hormones play a critical role in regulation of bone metabolism. In male mice lacking androgen receptor (AR), osteopenia and high turnover state in bone remodeling have been reported. However, androgen receptor's role in disuse-induced osteopenia is not known. Therefore, we examined the effects of AR deficiency on unloading-induced bone loss. Wild type or androgen receptor deficient mice (ARKO) were subjected to hind limb unloading (HU) or normal housing (Control). The groups of mice were as follows; wild type control mice (Group WT-Cont), ARKO control mice (Group ARKO-Cont), wild type HU mice (Group WT-HU), and ARKO-HU mice (Group ARKO-HU). HU reduced cancellous bone mass in ARKO (ARKO-HU) by about 70% compared to ARKO-Cont and this reduction rate was over two-fold more than that of wild type (WT-HU) (reduction by less than 30% compared to WT-Cont). Combination of ARKO and HU (ARKO-HU) resulted in the least levels of cortical bone mass and bone mineral density among the four groups. ARKO-HU group indicated the highest levels of systemic bone resorption marker, deoxypyridinoline. Osteoclast development levels in the cultures in ARKO-HU derived bone marrow cells were the highest among the four groups. These data suggest that combination of androgen receptor deficiency and hind limb unloading results in exacerbation of disuse-induced osteopenia due to the enhanced levels of bone resorption.

Follow-up of a self-resolving renal pseudoaneurysm using contrast-enhanced power Doppler ultrasonography

It has been standard practice to embolise a pseudoaneurysm caused by penetrating trauma whenever it is found, even in the absence of overt symptoms. This is a case report of a renal pseudoaneurysm (RPA) caused by a stab wound, which was safely monitored and followed using colour Doppler ultrasonography. On day 1, angiography showed a pseudoaneurysm of the renal artery in the parenchyma and ultrasonography showed blood flow into the pseudoaneurysm. Although abnormal blood flow into the kidney was seen, there appeared to be no leakage of blood from the pseudoaneurysm. The abnormal flow disappeared on day 12 and the area of the pseudoaneurysm became unclear from day 13. This report suggests the possibility that RPA caused by a stab wound could be an indication for conservative therapy under the following conditions: the RPA is detected initially; close monitoring using a colour Doppler ultrasound is possible; there is no leakage of blood from the right subclavian artery and there is a 2-week period of observation.

[Clinical analysis of bronchoplastic surgery for lung cancer after 2000]

We investigated surgical complications and prognosis of bronchoplasty and bronchoplasty with pulmonary angioplasty (broncho-angioplasty) for lung cancer. Between October 2000 and October 2007, 37 bronchoplastic procedures were done in 572 patients who underwent lung resections for lung cancer. Eleven (29.7%) bronchoplasties were done with pulmonary angioplasty. There was no operative mortality and 1 hospital mortality (2.7%) causing by myocardial infarction. Six of 11 postoperative complications were bronchial complications and 2 additional lung resections were needed. The 5-year survival for all patients was 55.2% and for bronchoplasty was 57.8%. Though the 5-year survival of broncho-angioplasty was not able to calculate at present, the 3-year survival of which was 72.9%. There was no death of patients with adenocarcinoma after introduction of pre-operative assessment by FDG-PET for lymph node metastasis. These data suggest that bronchoplasty and broncho-angioplasty are safe operative procedures and could provide acceptable intermediate survivals with modern multimodality diagnostic and therapeutic tools.

Adiponectin induces insulin secretion in vitro and in vivo at a low glucose concentration

AIMS/HYPOTHESIS

A decrease in plasma adiponectin levels has been shown to contribute to the development of diabetes. However, it remains uncertain whether adiponectin plays a role in the regulation of insulin secretion. In this study, we investigated whether adiponectin may be involved in the regulation of insulin secretion in vivo and in vitro.

METHODS

The effect of adiponectin on insulin secretion was measured in vitro and in vivo, along with the effects of adiponectin on ATP generation, membrane potentials, Ca2+ currents, cytosolic calcium concentration and state of 5'-AMP-activated protein kinase (AMPK). In addition, insulin granule transport was measured by membrane capacitance and total internal reflection fluorescence (TIRF) analysis.

RESULTS

Adiponectin significantly stimulated insulin secretion from pancreatic islets to approximately 2.3-fold the baseline value in the presence of a glucose concentration of 5.6 mmol/l. Although adiponectin had no effect on ATP generation, membrane potentials, Ca2+ currents, cytosolic calcium concentrations or activation status of AMPK, it caused a significant increase of membrane capacitance to approximately 2.3-fold the baseline value. TIRF analysis revealed that adiponectin induced a significant increase in the number of fusion events in mouse pancreatic beta cells under 5.6 mmol/l glucose loading, without affecting the status of previously docked granules. Moreover, intravenous injection of adiponectin significantly increased insulin secretion to approximately 1.6-fold of baseline in C57BL/6 mice.

CONCLUSIONS/INTERPRETATION

The above results indicate that adiponectin induces insulin secretion in vitro and in vivo.

[Problems in donor lung evaluation for transplantation with regard to airway infection]

The shortage of donor organs has been 1 of the major obstacles to solid organ transplantation. Typical lung donor criteria include clear lung field on chest radiograph, adequate oxygenation, acceptable lung compliance, and satisfactory bronchoscopic findings. To extend usage of available donors, liberalization of donor lung selection criteria has been facilitated, however, marginal donor lungs must be used with discretion, because donor lung injury, especially that related to infection, has a potential leading to early post-operative death of the recipient. From March 2000 to December 2006, we evaluated 15 braindead donors and at least 1 of the lungs from 9 donors was judged suitable for transplantation. One of 9 recipients developed severe pneumonia cased by carbapenems-resistant Pseudomonas aeruginosa possibly originating from the donor lungs, eventually leading to death. The chest radiograph and oxygenation of the donor had been satisfactory, however, a moderate amount of mucopurulent secretions was observed by bronchoscopic inspection and the donor had been given a cefozopran for 9 days before the procurement operation. Remaining 8 recipients were free from air-way infection in the early postoperative period. We discuss the status and problems of donor lung evaluation for transplantation with regard to donor lung infection.

Diversity of the osteoblastic phenotype

Studies of bone cells in culture have raised two salient questions: are the findings representative of the in vivo situation and can the conflicting data from different cell models be reconciled? Review of the literature indicates that all osteoblastic cells, defined by their origin or by their ability to produce mineralized matrix, have a few common properties: production of type I collagen; increased alkaline phosphatase activity; and parathyroid hormone-stimulated adenylate cyclase. Other features, such as osteocalcin and prostaglandin E production and the response to prostaglandin E, are selectively expressed by certain cell types. Pilot studies on mRNA levels of 'bone proteins' in developing calvaria suggest that such differences may reflect stages in osteoblastic differentiation. Immortalization of calvaria-derived cells using a SV40 large T antigen vector, which may freeze the cells in their particular state of differentiation (as proposed for leukaemia cells), yields phenotypes consistent with that hypothesis. Immortal cell lines may thus help to characterize osteoblastic differentiation. The diversity of osteoblast responses in culture to hormones and growth factors could be due to these phenotype differences but could also represent a subspecialization of differentiated cells. In addition, in the organism regulatory agents act in concert on a heterogeneous interactive cell population. Nonetheless cell cultures can be useful in screening for and predicting in vivo responses, as was shown by the 1,25-(OH)2D3 stimulation of osteocalcin, and for studying the molecular mechanisms of regulatory effects. Cell lines are also convenient for the production of specific proteins and cDNA libraries, and for the expression of specific genes.

Aromatase expression in a human osteoblastic cell line increases in response to prostaglandin E(2) in a dexamethasone-dependent fashion

Recent progress supports the importance of local estrogen secretion in human bone tissue to increase and maintain bone-mineral density. In a previous report, we found that forskolin (FSK) synergistically induces aromatase (CYP19: a rate-limiting enzyme for estrogen synthesis) expression in dexamethasone (Dex) dependent manner in a human osteoblastic cell line, SV-HFO [Watanabe M, Ohno S, Nakajin S. Forskolin and dexamethasone synergistically induce aromatase (CYP19) expression in the human osteoblastic cell line SV-HFO. Eur J Endocrinol 2005;152:619-24]. In this report, we investigated whether prostaglandin (PG) E(2) induces estrogen production, in other words, if PGE(2) exerts the same effect as FSK because PGE(2) is the major prostanoid in the bone and is one of the key molecules in the osteoblast. We found PGE(2) up-regulates aromatase activity synergistically, but this up-regulation depends on Dex. CYP19 gene expression was also increased synergistically by Dex and PGE(2). Promoter I.4 was activated synergistically by PGE(2) and Dex. PGE(2) receptor, EP(1), EP(2) and EP(4) were involved in the up-regulation of aromatase activity in response to PGE(2) in a Dex-dependent manner. The cAMP-PKA pathway and Ca(2+) signaling pathway were involved in the up-regulation of aromatase activity in response to PGE(2). Furthermore, glucocorticoid response element on promoter I.4 sequence was an essential minimum requirement for its activity and synergism of PGE(2) and Dex. These findings are the first report on osteoblastic cell line which uses predominantly promoter I.4 to drive aromatase expression. These findings also suggest that endogenous PGE(2) produced in bone mainly may synergistically support local estrogen production in osteoblastic cells in the presence of glucocorticoid.

Use of the novel phylogenetic marker dnaJ and DNA-DNA hybridization to clarify interrelationships within the genus Aeromonas

The interrelationships of 27 Aeromonas strains were investigated using dnaJ sequences and DNA-DNA hybridization. dnaJ sequence similarities showed a stronger relationship with DNA-DNA relatedness values than did 16S rRNA gene sequence similarities. Additionally, dnaJ sequence analysis, with interspecies divergence over 5.2 % in most cases, gave better resolution than 16S rRNA gene sequences for the differentiation of strains at the species level. Relationships among Aeromonas species were therefore elucidated on the basis of dnaJ sequences and DNA-DNA reassociation. Strains of Aeromonas encheleia and Aeromonas sp. HG11 were unquestionably grouped in the same genetic species, since they shared 98.7 % dnaJ sequence similarity and 82-85 % genomic relatedness. The phylogenetically close relationships obtained from dnaJ sequence analysis (1.7-3.3 % genetic distance) were corroborated by high DNA-DNA relatedness (73-97 %) to support the previous suggestion that Aeromonas culicicola and Aeromonas allosaccharophila are later heterotypic synonyms of Aeromonas veronii. Our findings will contribute to the clarification of controversial relationships in the genus Aeromonas and also demonstrate that analysis of dnaJ sequences can be a powerful tool for interspecies study of the genus.

The dnaJ gene as a novel phylogenetic marker for identification of Vibrio species

The utility of the dnaJ gene for identifying Vibrio species was investigated by analyzing dnaJ sequences of 57 type strains and 22 clinical strains and comparing sequence homologies with those of the 16S rDNA gene and other housekeeping genes (recA, rpoA, hsp60). Among the 57 Vibrio species, the mean sequence similarity of the dnaJ gene (77.9%) was significantly less than that of the 16S rDNA gene (97.2%), indicating a high discriminatory power of the dnaJ gene. Most Vibrio species were, therefore, differentiated well by dnaJ sequence analysis. Compared to other housekeeping genes, the dnaJ gene showed better resolution than recA or rpoA for differentiating Vibrio coralliilyticus from Vibrio neptunius and Vibrio harveyi from Vibrio rotiferianus. Among the clinical strains, all 22 human pathogenic strains, including an atypical strain, were correctly identified by the dnaJ sequence. Our findings suggest that analysis of the dnaJ gene sequence can be used as a new tool for the identification of Vibrio species.

Deficiency of CIZ, a nucleocytoplasmic shuttling protein, prevents unloading-induced bone loss through the enhancement of osteoblastic bone formation in vivo

Disuse osteoporosis is a major cause to increase the risk of fractures in bed-ridden patients whose numbers are increasing in our modern society. However, the mechanisms underlying the sensing of mechanical stress in bone are largely unknown. CIZ localizes at cell adhesion plaque and transfers into nuclear compartments and activates promoters of the genes encoding enzymes, which degrade matrix proteins to link signals from the cell adhesion site to nuclear events. We examined whether this nucleocytoplasmic shuttling protein would be involved in mediation of mechanical stress signaling. Unloading based on tail suspension reduced bone volume in wild-type mice. In contrast, CIZ-deficient mice revealed suppression in such reduction of bone mass due to unloading. Histomorphometric analysis revealed that unloading suppressed the levels of osteoblastic bone formation parameters, and such suppression of bone formation parameters was blocked by CIZ-deficiency. Osteoclastic bone resorption parameters were similar regardless of CIZ-deficiency after 2-week unloading. Mineralized nodule formation in the cultures of bone marrow cells obtained from the bone of mice subjected to unloading was suppressed in wild-type mice. CIZ deficiency blocked such reduction in nodule formation induced by unloading. These data indicated that nucleocytoplasmic shuttling protein, CIZ, plays a pivotal role in the response of bone mass in unloading condition.

Phylogeny and species identification of the family Enterobacteriaceae based on dnaJ sequences

Phylogenetic relations within the family Enterobacteriaceae were analyzed using partial dnaJ sequences of 165 strains belonging to 93 species from 27 enterobacterial genera. The dnaJ phylogeny was in relative agreement with that constructed by 16S rDNA sequences, but more monophyletic groups were obtained from the dnaJ tree than from the 16S rDNA tree. The degree of divergence of the dnaJ gene was approximately 6 times greater than that of 16S rDNA. Also, the dnaJ gene showed the most discriminatory power in comparison with tuf and atpD genes, facilitating clear differentiation of any 2 enterobacterial species by dnaJ sequence analysis. The application of dnaJ sequences to the identification was confirmed by assigning 72 clinical isolates to the correct enterobacterial species. Our data indicate that analysis of the dnaJ gene sequences can be used as a powerful marker for phylogenetic study and identification at the species level of the family Enterobacteriaceae.

dnaJ gene sequence-based assay for species identification and phylogenetic grouping in the genus Staphylococcus

In the last few years, many attempts have been made to use conserved gene sequences for identification and for phylogenetic studies of Staphylococcus species. In an effort to identify a more reliable approach, a dnaJ gene sequence-based database was created. In this study, an approximately 883 bp portion of the dnaJ gene sequence from 45 staphylococcal type strains was compared with 16S rRNA and other conserved gene (hsp60, sodA and rpoB) sequences available in public databases. Nucleotide sequence comparisons revealed that the staphylococcal dnaJ gene showed higher discrimination (mean similarity 77.6 %) than the 16S rRNA (mean similarity 97.4 %), rpoB (mean similarity 86 %), hsp60 (mean similarity 82 %) and sodA (mean similarity 81.5 %) genes. Analysis of the dnaJ gene sequence from 20 Staphylococcus isolates representing two clinically important species showed <1 % sequence divergence. Phylogenetic data obtained from the dnaJ gene sequence were in general agreement with those of 16S rRNA gene sequence analysis and DNA-DNA reassociation studies. In conclusion, the dnaJ gene sequence-based assay is an effective alternative to currently used methods, including 16S rRNA gene sequencing, for identification and taxonomical analysis of Staphylococcus species.

ED-71, a novel vitamin D analog, promotes bone formation and angiogenesis and inhibits bone resorption after bone marrow ablation

ED-71, a novel analog of 1alpha,25-(OH)2 D3, increases bone mass to a greater extent than alfacalcidol, an 1alpha,25-(OH)2 D3 prodrug. In this study, we used a murine bone marrow ablation model to compare the effect of ED-71 on bone formation and resorption in vivo with that of 1alpha,25-(OH)2 D3. We discovered that bone matrix remodeling occurring within the first week after bone marrow ablation was enhanced by a single injection of ED-71, but not by 1alpha,25-(OH)2 D3. This enhancement was associated with an increase in bone surface. Trabecular bone resorption occurring from 1 to 2 weeks after the procedure was suppressed by a single injection of ED-71, but not 1alpha,25-(OH)2 D3, with treated mice exhibiting a reduction in osteoclast numbers, despite increases in osteoblast surface. As seen with the single injection, daily administration of ED-71 also enhanced bone modeling. Bone marrow osteoblast differentiation was also augmented by ED-71 pretreatment. Furthermore, ED-71 treatment immediately after bone marrow ablation enhanced angiogenesis within the bone marrow cavity via enhancement of VEGF(120) expression. In this paper, we clearly demonstrate that ED-71 is an orally administered small molecular weight compound with an anabolic effect on bone metabolism.

Radicals produced by blue-light–resin interactions alter the redox status of THP1 human monocytes

Resin composites are widely used in dentistry, and are polymerized in situ using a blue-light activated, free-radical polymerization mechanism. Blue light (400-500nm) is used to activate camphoroquinone (CQ), which decomposes to form free radicals that are stabilized by dimethyl-p-toludine (DMPT). CQ and DMPT are applied near tooth pulpal tissues and are irradiated during restorative procedures, suggesting that pulpal cells are exposed to free radicals. Because glutathione is a major component of the cellular redox management system, we tested the hypothesis that blue light irradiation would shift cellular glutathione redox balance of cells exposed to CQ and DMPT. We also measured NFkappaB activation, a redox-sensitive transcription factor that regulates inflammatory responses and glutathione synthetic enzyme levels. THP1 human monocytes were exposed to sublethal levels of CQ (0.4 mM) or DMPT (1.0 mM), with or without blue light exposure (25 J/cm(2)) from a quartz-tungsten-halogen source. The ratio of reduced to oxidized glutathione was measured using as assay based on 5,5'-dithio-bis(2-nitrobenszoic acid). NFkappaB transactivation was measured by transfection of an NFkappaB-containing plasmid linked to a luciferase reporter. Our results showed that blue light, CQ, or DMPT alone had no significant effect on cellular glutathione redox balance, but that the combination of these agents induced a marked oxidative bias, and reduced total glutathione levels up to 50%. On the other hand, light, CQ, and DMPT alone or in combination suppressed NFkappaB transactivation by >70%. Our results suggest that CQ and DMPT pose risks to pulpal tissues with or without blue light irradiation, and that multiple, interacting mechanisms shape the response to these agents.

Upregulation of retinal transglutaminase during the axonal elongation stage of goldfish optic nerve regeneration

Fish CNS neurons can repair their axons following nerve injury, whereas mammalian CNS neurons cannot regenerate, and become apoptotic within 1-2 weeks after the nerve lesion. One explanation for these differences is that one, or several molecules are upregulated in fish CNS neurons during nerve regeneration, and this same molecule is downregulated in mammalian CNS neurons before the development of apoptosis caused by nerve injury. A molecule satisfying these criteria might successfully rescue and repair the mammalian CNS neurons. In this study, we looked for such a candidate molecule from goldfish retinas. Transglutaminase derived from goldfish retina (TG(R)) was characterized as a regenerating molecule after optic nerve injury. A full-length cDNA for TG(R) was isolated from the goldfish retinal cDNA library prepared from axotomized retinas. Levels of TG(R) mRNA and protein increased only in the retinal ganglion cells (RGCs) between 10 and 40 days after optic nerve transection. Recombinant TG(R) protein enhanced neurite outgrowth from adult fish RGCs in culture. Specific interference RNA and antibodies for TG(R) inhibited neurite outgrowth both in vitro and in vivo. In contrast, the level of TG(R) protein decreased in rat RGCs within 1-3 days after nerve injury. Furthermore, the addition of recombinant TG(R) to retinal cultures induced striking neurite outgrowth from adult rat RGCs. These molecular and cellular data strongly suggest that TG(R) promotes axonal elongation at the surface of injured RGCs after optic nerve injury.

Calreticulin as a new histone binding protein in mitotic chromosomes

Calreticulin (CRT) is a multifunctional Ca(2+)-binding protein that mainly functions in the endoplasmic reticulum as a molecular chaperone for newly synthesized proteins. Recently we reported the protein composition of human metaphase chromosomes (Uchiyama et al., 2004), which included CRT. Here we describe new characteristics of CRT in vitro as well as its localization on the surface of metaphase chromosomes in vivo. CRT was detected in the chromosomal fraction by Western blotting and its binding partners were identified as core and linker histones by ligand overlay assay. Surface plasmon resonance sensor analyses revealed that CRT is bound to chromatin fibers. Moreover, we found that CRT has both supercoiling activity, which assists core histone assembly into chromatin fibers, and binding ability to histone H2A/H2B dimers and histone H3/H4 tetramers. Unlike the chromosome scaffold proteins, indirect immunofluorescent staining revealed that CRT is located on the surface of metaphase chromosomes. These results suggest that CRT plays a role which involves chromatin dynamics on the surface of mitotic chromosomes.

TIMP-2 upregulates RECK expression via dephosphorylation of paxillin tyrosine residues 31 and 118

We previously demonstrated that TIMP-2 increases the association of Crk with C3G and via subsequent activation of Rap1 enhances the expression of RECK, a membrane-anchored MMP inhibitor. In the present study, we investigate the mechanism of how the TIMP-2 signal is transduced from the alpha3beta1 integrin receptor to the Crk-C3G-Rap1 molecular complex. TIMP-2 treatment of human microvascular endothelial cells (hMVECs) increased the phosphorylation levels of Src at Tyr-527, the negative regulatory site, through enhanced association of Src with Csk. This results in the reduction of Src kinase activity and dephosphorylation of paxillin at Tyr-31/118, the target sites for Src kinase phosphorylation and also the binding sites for the downstream effector Crk. Such TIMP-2 effects accompany the disassembly of paxillin-Crk-DOCK180 molecular complex and, in turn, Rac1 inactivation. On the contrary, levels of paxillin-Crk-C3G complex formation are not reduced, rather slightly increased, which is consistent with our previous finding. Therefore, TIMP-2-mediated inhibition of Src kinase activity leads to the signaling switch from Rac1 to Rap1, thereby leading to enhanced RECK expression.

Preventive effects of CIDR-based protocols on premature ovulation before timed-AI in Ovsynch in cycling beef cows

Ovsynch is a program developed to synchronize ovulation for timed breeding. In this paper, the authors investigate whether controlled internal drug release (CIDR)-based protocols prevent premature ovulation before timed-artificial insemination (AI) when Ovsynch is started a few days before luteolysis in cycling beef cows. Nine beef cows at 16 days after oestrus were treated with (1) Ovsynch, i.e. gonadotropin releasing hormone (GnRH) analogue on day 0, prostaglandin (PG) F(2alpha) analogue on day 7 and GnRH analogue on day 9 with timed-AI on day 10, (n=3); (2) Ovsynch+CIDR (Ovsynch protocol plus a CIDR for 7 days from day 0, n=3), or (3) oestradiol benzoate (OB)+CIDR+GnRH (OB on day 0 in lieu of the first GnRH treatment, followed by the Ovsynch+CIDR protocol, n=3). In the Ovsynch group (1) plasma progesterone concentrations fell below 0.5 ng/mL earlier (day 5) than in both CIDR-treated groups (2) and (3), where this occurred on day 8. Plasma oestradiol-17beta concentrations peaked on day 8 in the Ovsynch group and on day 9 in both CIDR-treated groups. The dominant follicle ovulated on day 10 in the Ovsynch group and on day 11 in both CIDR-treated groups. Thus, both CIDR-based protocols prevented premature ovulation before timed-AI in Ovsynch when the protocol was started a few days before luteolysis. This reflects the fact that progesterone levels remained high until the beef cattle were treated with PGF(2alpha).

Intra- and extracellular reactive oxygen species generated by blue light

Blue light from dental photopolymerization devices has significant biological effects on cells. These effects may alter normal cell function of tissues exposed during placement of oral restorations, but recent data suggest that some light-induced effects may also be therapeutically useful, for example in the treatment of epithelial cancers. Reactive oxygen species (ROS) appear to mediate blue light effects in cells, but the sources of ROS (intra- versus extracellular) and their respective roles in the cellular response to blue light are not known. In the current study, we tested the hypothesis that intra- and extracellular sources of blue light-generated ROS synergize to depress mitochondrial function. Normal human epidermal keratinocytes (NHEK) and oral squamous cell carcinoma (OSC2) cells were exposed to blue light (380-500 nm; 5-60 J/cm(2)) from a dental photopolymerization source (quartz-tungsten-halogen, 550 mW/cm(2)). Light was applied in cell-culture media or balanced salt solutions with or without cells present. Intracellular ROS levels were estimated using the dihydrofluorescein diacetate (DFDA) assay; extracellular ROS levels were estimated using the leucocrystal violet assay. Cell response was estimated using the MTT mitochondrial activity assay. Blue light increased intracellular ROS equally in both NHEK and OSC2. Blue light also increased ROS levels in cell-free MEM or salt solutions, and riboflavin supplements increased ROS formation. Extracellularly applied ROS rapidly (50-400 muM, <1 min) increased intracellular ROS levels, which were higher and longer-lived in NHEK than OSC2. The type of cell-culture medium significantly affected the ability of blue light to suppress cellular mitochondrial activity; the greatest suppression was observed in DMEM-containing or NHEK media. Collectively, the data support our hypothesis that intra- and extracellularly generated ROS synergize to affect cellular mitochondrial suppression of tumor cells in response to blue light. However, the identity of blue light targets that mediate these changes remain unclear. These data support additional investigations into the risks of coincident exposure of tissues to blue light during material polymerization of restorative materials, and possible therapeutic benefits.

Unloading-induced bone loss was suppressed in gold-thioglucose treated mice

Loss of mechanical stress causes bone loss. However, the mechanisms underlying the unloading-induced bone loss are largely unknown. Here, we examined the effects of gold-thioglucose (GTG) treatment, which destroys ventromedial hypothalamus (VMH), on unloading-induced bone loss. Unloading reduced bone volume in control (saline-treated) mice. Treatment with GTG-reduced bone mass and in these GTG-treated mice, unloading-induced reduction in bone mass levels was not observed. Unloading reduced the levels of bone formation rate (BFR) and mineral apposition rate (MAR). GTG treatment also reduced these parameters and under this condition, unloading did not further reduce the levels of BFR and MAR. Unloading increased the levels of osteoclast number (Oc.N/BS) and osteoclast surface (Oc.S/BS). GTG treatment did not alter the basal levels of these bone resorption parameters. In contrast to control, GTG treatment suppressed unloading-induced increase in the levels of Oc.N/BS and Oc.S/BS. Unloading reduced the levels of mRNA expression of the genes encoding osteocalcin, type I collagen and Cbfa1 in bone. In contrast, GTG treatment suppressed such unloading-induced reduction of mRNA expression. Unloading also enhanced the levels of fat mass in bone marrow and mRNA expression of the genes encoding PPARgamma2, C/EBPalpha, and C/EBPbeta in bone. In GTG-treated mice, unloading did not increase fat mass and the levels of fat-related mRNA expression. These results indicated that GTG treatment suppressed unloading-induced alteration in bone loss.

Effect of CIDR-based protocols for timed-AI on the conception rate and ovarian functions of Japanese Black beef cows in the early postpartum period

Our objectives were to compare: (1) conception rates (in early postpartum Japanese Black beef cows) to timed-artificial insemination (timed-AI) among Ovsynch and Ovsynch plus CIDR protocols, and a protocol that used estradiol benzoate (EB) in lieu of the first GnRH of the Ovsynch plus CIDR; and (2) the effects of these protocols on blood concentrations of ovarian steroids. Cows in the control group (Ovsynch; n=35) underwent a standard Ovsynch protocol (GnRH analogue on Day 0, PGF(2 alpha) analogue on Day 7 and GnRH analogue on Day 9), with timed-AI on Day 10, approximately 20 h after the second GnRH treatment. Cows in the Ovsynch+CIDR group (n=31) received a standard Ovsynch protocol plus a CIDR for 7 days (starting on Day 0). Cows in the third treatment group (EB+CIDR+GnRH; n=41) received 2mg of EB on Day 0 in lieu of the first GnRH treatment, followed by the same treatment as in the Ovsynch+CIDR protocol. The conception rate tended to be greater in the Ovsynch+CIDR group (67.7%, P<0.15) and was greater in the EB+CIDR+GnRH (73.2%, P<0.05) and CIDR-combined (both CIDR-treated groups were combined) groups (70.8%, P<0.05) than in the Ovsynch group (48.6%). Plasma progesterone concentrations were higher on Day 7 (P<0.01) and lower on Days 14, 17 and 21 (P<0.001) in the CIDR-combined group than in the Ovsynch group. Plasma estradiol-17beta concentrations were higher on Day 7 in the Ovsynch group of non-pregnant cows than in the CIDR-combined group of non-pregnant cows and in an all-combined group (all treatment groups combined) of pregnant cows (P<0.01). Furthermore, estradiol-17beta concentrations were lower on Day 9 in the Ovsynch and CIDR-combined groups of non-pregnant cows than in the all-combined group of pregnant cows (P<0.05). In conclusion, both protocols using CIDR improved conception rates following timed-AI in early postpartum suckled Japanese Black beef cows relative to the Ovsynch protocol. Treatment with a CIDR may prevent early maturation of follicles observed in non-pregnant cows treated with the Ovsynch protocol, by maintaining elevated blood progesterone concentrations until PGF(2 alpha) treatment.

The role of edaravone on the impairment of endothelial barrier function induced by acute oxidative stress in cultured human umbilical vein endothelial cell monolayer

BACKGROUND

The aim was to determine the effects of a novel free radical scavenger, edaravone, 3-methyl-1-phenyl-2-pyrazoline-5-one (ED), against endothelial barrier dysfunction induced by acute oxidative stress in cultured human umbilical vein endothelial cells (HUVECs).

METHODS

To estimate the integrity of the HUVEC monolayer, transendothelial electrical resistance (TEER) was measured for 3 hours. We investigated the permeability change of the monolayer by measuring the concentration of fluorescence in isothiocyanate-labeled dextran (FITC-Dx), and estimated the degree of oxidative stress in terms of hydrogen peroxide (H2O2) in the apical chambers.

RESULTS

The TEER changes in both xanthine oxidase (XO)+xanthine (X) and X/XO+ED group were significantly lower than the control group (p < 0.001). The amount of 4 FITC-Dx in the XO+X group was significantly higher than the control group at 3 hours (p < 0.001). In the XO+X group, the concentration of H2O2 was significantly higher than control and the X/XO+ED group (p < 0.001 each). Thus, edaravone improved the disturbed endothelial barrier function induced by acute oxidative stress.

CONCLUSIONS

The permeability increase induced by acute oxidative stress was prevented by free radical scavenger edaravone significantly in vitro. This radical scavenger may have clinical applications to protect against endothelial barrier dysfunction.

Absence of an association between the polymorphisms in the genes encoding adiponectin receptors and type 2 diabetes

AIMS/HYPOTHESIS

Secreted by adipocytes, adiponectin is a hormone that acts as an antidiabetic and anti-atherogenic adipokine. We recently cloned the genes encoding two adiponectin receptors (ADIPOR1 and ADIPOR2). The aim of this study was to examine whether ADIPOR1 and/or ADIPOR2 play a major role in genetic susceptibility to insulin resistance or type 2 diabetes in the Japanese population.

METHODS

By direct sequencing and a search of public databases, we identified single nucleotide polymorphisms (SNPs) in ADIPOR1 and ADIPOR2, and investigated whether these SNPs are associated with insulin resistance and type 2 diabetes in the Japanese population.

RESULTS

The linkage disequilibrium (LD) in the chromosomal region of ADIPOR1 was almost completely preserved, whereas the LD in ADIPOR2 was less well preserved. None of the SNPs in ADIPOR1 or ADIPOR2 were significantly associated with insulin resistance or type 2 diabetes. No differences in ADIPOR1 or ADIPOR2 haplotype frequencies were observed between type 2 diabetic and non-diabetic subjects.

CONCLUSIONS/INTERPRETATION

Genetic variations in ADIPOR1 or ADIPOR2 are unlikely to lead to a common genetic predisposition to insulin resistance or type 2 diabetes in the Japanese population.

Examination of quantitative and fractal analysis of sway characteristics of the center of foot pressure movement during a static upright posture. Analysis based on alcohol intake

AIM

This study aimed to examine the sway characteristics of center of foot pressure (CFP) movement during a static upright posture under the influence of alcohol by using quantitative and fractal analysis.

METHODS

Eleven healthy young people participated. They drank in a range of 0.54-1.83 ml/kg of alcohol, standardized by body mass, within 10 min. Blood pressure, heart rate, 2 types of nervous function tests and the CFP movement were measured before and after the alcohol intake. Thirty-six parameters of the CFP movement were used for quantitative analysis. Diffusion coefficient, scaling exponent and critical point coordinates were used in fractal analysis.

RESULTS

Quantitative analysis confirmed that the CFP parameters such as distance, velocity and area were significantly changed, although the parameters evaluating cyclical characteristics and center average were not. Fractal analysis confirmed that critical point coordinates existed at time-lag=1.0 before and after the alcohol intake, and the short-term region (ST) and long-term region (LT) could be separated. A diffusion coefficient in the ST was larger than that in the LT, and the scaling exponent was over 0.5 in the ST and under 0.5 in the LT.

CONCLUSIONS

Influences of alcohol intake were found in amount of body-sway, but not in the displacement or periodicity of the CFP parameters. Fractal analysis confirmed that CFP movement was dependent on time-series, and its characteristics changed before and after the time-series critical point and was unsteady.

Mother-infant skin-to-skin contact after delivery results in early recognition of own mother's milk odour

AIM

To determine the effects of mother-infant skin-to-skin contact immediately after birth on infant recognition of their own mother's milk odour and breastfeeding duration until 1 y of age.

METHODS

Sixty healthy, full-term neonates were randomly assigned to group A with skin-to-skin contact and group B without. One and 4 d after birth, infant responses to the following odour stimuli were observed: own mother's milk, another mother's milk, formula, orange juice and distilled water. Infant facial action was videotaped and the frequency of mouthing movements was evaluated for each stimulus. Nutritional assessment, focused particularly on breastfeeding, was performed every 3 mo on participating infants. Statistical analysis comparing the frequency of mouthing movements with the aforementioned five different odour exposures was performed by ANOVA with Fisher's PLSD. Kaplan-Meier analysis with a log-rank test was used to compare breastfeeding rates between groups.

RESULTS

Infants in both groups responded differently to mother's milk odour (either their own or another mother's milk) compared to the other stimuli on days 1 and 4. However, infants in group A demonstrated a larger difference in mouthing movements between their own and another mother's milk odour at 4 d of age (2.6 +/- 1.6) compared to infants in group B (0.9 +/- 2.0, p = 0.01). Infants in group A were breastfed an average of 1.9 mo longer than the others.

CONCLUSION

Our study provides evidence that mother-infant skin-to-skin contact for more than 50 min immediately after birth results in enhanced infant recognition of their own mother's milk odour and longer breastfeeding duration.

Alcohol consumption and other risk factors for self-reported diabetes among middle-aged Japanese: a population-based prospective study in the JPHC study cohort I

AIMS

Few prospective studies have examined the relationship between lifestyle characteristics and the incidence of diabetes mellitus in an Asian general population. This study was undertaken to evaluate the risk factors for Type 2 diabetes in a population-based prospective study of middle-aged Japanese.

METHODS

We investigated 12,913 men and 15,980 women, aged 40-59 years at baseline (year 0), who participated in the Japan Public Health Center-based prospective study on cancer and cardiovascular diseases (JPHC Study) Cohort I. The participants were followed for up to 10 years. Incident cases of diabetes were identified by self-reporting of a physician's diagnosis on two questionnaires sent to each participant, one at year 5 and the second at year 10.

RESULTS

During the 10-year follow-up, 703 men and 482 women reported newly diagnosed diabetes. Age, body mass index (BMI), family history of diabetes and cigarette smoking were independent risk factors in both genders by multivariate analysis. Among men with a BMI < or = 22 kg/m2, a significant positive association was observed between the diabetes incidence and moderate (23.0 < 46.0 g/day) to high (> 46.0 g/day) alcohol consumption, odds ratio 1.91 (95% CI, 1.05-3.46) and 2.89 (1.63-5.11), respectively. Among men with a BMI > 22 kg/m2, a small non-significant increase in odds ratio was observed with alcohol consumption.

CONCLUSIONS

Established risk factors for diabetes in western populations were also identified as predictors of the disease among Japanese. Moderate to high alcohol consumption was positively associated with the incidence of diabetes in Japanese lean (BMI < or = 22 kg/m2) men.

Physical characteristics of low and medium energy collimators for 123I imaging and simultaneous dual-isotope imaging

Septal penetration of high energy photons may degrade 123I images obtained with a low energy collimator. We evaluated the physical characteristics of a low energy, high resolution (LEHR) collimator, special LEHR (SLEHR) collimator, and medium energy collimator for 123I studies. The cross-talk of 99mTc and 123I into the 201Tl window was also examined. Sensitivity and spatial resolution were measured with each collimator. Point sources of 99mTc and 123I were imaged at various source-collimator distances using multiple energy windows, and the effects of collimator choice on energy spectrum and spatial distribution of photopeak counts were assessed. For 99mTc, both sensitivity and resolution were similar with the low energy collimators, and higher sensitivity and lower resolution were observed with the medium energy collimator. For 123I, the full width at tenth maximum was larger for 123I than for 99mTc when using the LEHR collimator. Acquisitions with multiple energy windows revealed severe degradation due to septal penetration in imaging 123I with the LEHR collimator, especially at short distances. The degradation was reduced with the SLEHR collimator and further with the medium energy collimator. In both 99mTc and 123I imaging, cross-talk into the 201Tl window was larger at shorter distances and the largest with the LEHR collimator. In conclusion, variation in collimator geometry causes differences in the effect of septal penetration on 123I images and in cross-talk into the 201Tl window. The SLEHR collimator may be suitable for use in high resolution 123I imaging and simultaneous 99mTc/201Tl imaging. Use of the medium energy collimator appears to be preferable in quantitative 123I studies.

Dental adhesive compounds alter glutathione levels but not glutathione redox balance in human THP-1 monocytic cells

The use of hydrophilic dental monomers in dentin bonding agents has vastly improved resin-dentin bond strengths, but incomplete polymerization of these monomers and their leaching into adjacent (pulpal) oral tissues has raised concerns about their biocompatibility. The sublethal effects of these resins are virtually unknown, but their electrophilic nature led to the hypothesis that they may alter cellular oxidative stress pathways. Glutathione balance between reduced (GSH) and oxidized (GSSG) is a major mechanism by which cells maintain redox balance and was therefore the focus of the current investigation. THP-1 human monocytic cells were exposed to hydroxyethyl methacrylate (HEMA), benzoyl peroxide (BPO), camphorquinone (CQ), or triethyelene glycol dimethacrylate (TEGDMA) for 24 h at sublethal doses, then GSH and GSSG levels were measured by means of Ellman's method adapted for cell culture. The results indicate that these dental resin compounds act at least partly via oxidative stress by increasing GSH levels at sublethal concentrations. However, the GSH-GSSG ratio was relatively unaffected. Only BPO altered the GSH-GSSG ratio at 24 h, again at sublethal levels (7.5-15 micromol/L). The results support the hypothesis that resin monomers act, at least in part, via oxidative stress, and that oxidative-stress pathways should be one focus of future investigations of monomer biocompatibility.

Regression of idiopathic thrombocytopenic purpura after endoscopic mucosal resection of gastric mucosa associated lymphoid tissue lymphoma

Recent reports have suggested an association between Helicobacter pylori infection and both gastric mucosa associated lymphoid tissue (MALT) lymphoma and thrombocytopenic purpura. Although treatments eradicating H pylori lead to regression of these diseases in some cases, the exact mechanisms are still controversial. This case report describes a patient with thrombocytopenic purpura accompanied by an early stage gastric MALT lymphoma. Endoscopic mucosal resection of the lesion in this patient led to dramatic regression of thrombocytopenic purpura, and t(11;18)(q21;q21), which means resistance more likely to H pylori eradication therapy, was confirmed by fluorescence in situ hybridisation. There is no evidence of recurrence and his platelet count is within normal limits after 24 months of follow up. This is the first case report describing regression of thrombocytopenic purpura after mucosal resection of a gastric MALT lymphoma. We suggest that while some cases of thrombocytopenic purpura may be induced by H pylori, others may be due to an autoreactive antibody produced by MALT lymphoma B cells.

Detection of norovirus and sapovirus infection among children with gastroenteritis in Ho Chi Minh City, Vietnam

This report describes norovirus (NoV) and sapovirus (SaV) infections in hospitalized children with acute sporadic gastroenteritis in Ho Chi Minh City, Vietnam. Stool specimens collected between December 1999 and November 2000 were examined for NoV and SaV using reverse transcription-PCR and phylogenetic analysis. NoVs were detected in 72 of 448 rotavirus-negative specimens, counted as part of an overall annual detection rate of 5.4% (72 of 1,339 children). This included four NoV genogroup I (GI) strains and 68 NoV GII strains. Only one SaV GI strain was detected in the rotavirus-negative specimens. Over 73% of the NoV sequences belonged to GII/4 (Lordsdale cluster) and were detected in all months except March. We also detected GII/3 strains (Saitama U201 cluster), a naturally occurring recombinant NoV, between January 2000 and March 2000 but not after this period. Other NoV strains belonging to GI/4, GI/8, GII/1, and GII/7 were also detected but were infrequent. In addition, two almost identical NoV GII strains (strains 026 and 0703) collected six months apart were classified into a new genotype that includes the Mc37 strain, which was previously shown to be a recombinant NoV. During this one-year study, the NoV prevailed at the end of the rainy season and the beginning of the dry season. Further epidemiological studies may be necessary to determine whether the GII/4 strains continue to dominant in this region.

Serological and genetic characterisation of a unique strain of adenovirus involved in an outbreak of epidemic keratoconjunctivitis

AIMS

To characterise a novel strain of adenovirus (Ad) type Ad8 (genome type Ad8I) involved in an epidemic keratoconjunctivitis (EKC) outbreak in Hiroshima city using serological testing and sequence analysis of the fibre and hexon gene.

METHODS

A neutralisation test (NT) was performed in microtitre plates containing a confluent monolayer of A549 cells using 100 tissue culture infectious doses of virus and type specific antisera. The haemagglutination inhibition test was also carried out in microtitre plates with rat erythrocytes using four haemagglutination units of virus and twofold dilutions of serum. The fibre gene was sequenced by generating overlapping polymerase chain reaction products or by direct sequencing of genomic DNA. Primer selection was based on alignment of the fibre genes of human adenovirus serotypes Ad8, Ad19, Ad37, Ad9, and Ad15 available from Gene Bank.

RESULTS

The virus strain was specifically neutralised by anti-Ad8 antibodies, although there was a major crossreaction with anti-Ad9 antibodies. Haemagglutination was equally inhibited by anti-Ad8 and anti-Ad9 antibodies. The predicted amino acid sequences of the hypervariable regions (HVRs) of the Ad8I hexon gene showed higher homology with Ad9 (83.3%) than with Ad8 (62.0%). However, the Ad8I fibre knob was more homologous to Ad8 (94.4%) than to Ad9 (91.6%).

CONCLUSIONS

Ad8I is a unique strain of adenovirus because of its lower genomic homology with Ad8, major crossreactivity with Ad9 in NT, and mixed genetic organisation of HVRs of the hexon gene. These factors may have enabled the virus to circumvent acquired immunity, resulting in the outbreak.

Tissue reconstruction process in the area of peri-tumoural oedema caused by glioblastoma--immunohistochemical and graphical analysis using brain obtained at autopsy

BACKGROUND

In the area of peri-tumoural oedema, proteolytic agents derived from the tumour cause tissue degradation, which promotes tumour cell invasion.

METHOD

We investigated the biological processes in the area of peri-tumoural oedema, using a brain obtained at autopsy from a patient who died from glioblastoma. Immunohistochemistry was performed to detect vascular endothelial growth factor (VEGF), c-myc, p53, paternally expressed gene-3 (PEG-3), transforming growth factor beta (TGFB), and tumour necrosis factor alpha (TNFA). The data were translated into colour graphics and the localization of these proteins was analyzed.

FINDINGS

In the area of peri-tumoural oedema, Ki-67 and p53 positive cells were observed with TGFB expression. Moreover, c-myc, PEG-3, VEGF, and TNFA were also expressed strongly in the glial cells or extra-cellular spaces in the area of peri-tumoural oedema.

INTERPRETATION

These data suggest that in the area of peri-tumoural oedema, tissue reconstruction processes take place with concomitant anti-tumour activities. The expression of c-myc, VEGF, and TNFA in the area of peri-tumoural oedema may indicate that these proteins are not utilized for tumour growth, but may be used to guard the brain against tumour invasion. Peri-tumoural oedema does not only indicate the tissue damage caused by tumour, but many tissue reconstruction processes take place in these areas against tumour cell invasion.

Effects of ras and rap1 on electrical excitability of differentiated ng108-15 cells

Effects of two small G-proteins, Rap1 and Ras, on the sodium channel activity in NG108-15 cells were studied using sindbis virus-mediated gene transfer. When an activated Rap1A mutant (Rap1-12V, the activated mutant of Rap1 carrying glycine to valine substitution at codon 12) or a dominant-negative H-Ras mutant (Ras-17N, carrying serine to asparagine substitution at codon 17) was expressed in differentiated NG108-15 cells, the proportion of cells generating action potential decreased and the amplitudes of sodium current diminished. This effect was sensitive to an inhibitor of protein kinase A. The effects of a cyclic AMP (cAMP) analog (dibutyl cAMP) on sodium current in these cells were biphasic: inhibitory at lower concentrations (<100 microM) and enhancing at higher concentrations (200-500 microM). The inhibitory phase of cAMP effect was suppressed by an activated Ras mutant (Ras-12V) while the enhancing phase was suppressed by Rap1-12V. These data are consistent with the model that Rap1 and Ras function as counteracting regulators of voltage-gated sodium current through cAMP-dependent mechanisms.

[The establishment of the styles of video-assisted thoracoscopic surgery for spontaneous pneumothorax]

Video-assisted thoracoscopic surgery (VATS) has been widely used in the treatment of a pneumothorax, but the high incidence of recurrence from spontaneous pneumothorax after VATS is an important problem. In this study, we classified the groups into two categories from the thoracoscopic observations, and discussed whether or not there was reappearance of pneumothorax. In addition, we examined whether adjunctive procedure contributes to recurrent of pneumothorax after operation or not. We concluded that there is a tendency to recurrence in the group with multiple and skip lesions in the lung, and then concluded that the cases apical covering with absorbable material sheet and the use of fibrin glue spray was thought to be effective of recurrence of pneumothorax in cases of multiple and skip lesions from the intraoperative findings through the thoracoscopes. Finally, we examined application of Foley catheter for spontaneous pneumothorax under VATS. It is possible that the application of Foley catheter to prevention against recurrence of pneumothorax is a valid method.

Hg2+ and Ni2+ alter induction of heat shock protein-72 in THP-1 human monocytes

The biological liabilities that result from the release of metal ions from biomedical alloys, particularly Ni(2+) and Hg(2+), continue to be a concern. Heat-shock proteins (HSP) are a class of molecular chaperones that may be induced under conditions of cellular stress, including oxidative stress. Our hypothesis was that because Hg(2+) and Ni(2+) alter other cellular stress responses such as glutathione levels and cytokine secretion, these metal ions may alter HSP induction in monocytes, which are key cells in the response of tissues to biomedical alloys. THP-1 monocytes were exposed to sublethal concentrations of Hg(2+) or Ni(2+) for 1 h with or without heat stress (43 degrees C), then allowed to recover at 37 degrees C for 2-6 h. HSP72 was measured using immunoblotting with phosphorimage quantification. Hg(2+) exposures of 2-10 micromol/L induced HSP72 without heat stress. With heat stress, HSP72 levels were altered by Hg(2+) versus heat stress alone. The response depended on the concentration of Hg(2+) and the recovery time. Hg(2+) at 10 micromol/L caused uniformly lower HSP72 levels. Ni(2+) exposures of 20-100 micromol/L did not induce HSP72 without heat stress, but significantly altered heat-induced HSP72 expression, with a significant increase in expression over heat alone at 40 and 100 micromol/L. Results from the current study support the hypothesis that these metal ions can, at concentrations relevant to those released from biomedical alloys, modulate HSP expression in human monocytes. The modulation of HSP expression indicates an early sign of cellular stress that may be important to the overall biological response to biomedical alloys containing and releasing these metal ions.