Peeled volume models of a whole body to enhance comprehension of anthropological bone landmarks.

BACKGROUND: In physical anthropology, bone landmarks are palpated in living humans for the identification of corresponding skin landmarks and exact biometry. The purpose of this study is to help comprehend the locations and depths of representative bone landmarks all over the body. MATERIALS AND METHODS: The sectioned images of a male cadaver's whole body were used to build a volume model, which was continuously peeled at 1 mm thicknesses to disclose 27 selected landmarks in the anterior, lateral, or posterior views. RESULTS: The captured views of peeled volume models along with the labels of the bone landmarks were loaded to browsing software that was distributed for free. The browsing software containing the peeled volume models will enhance convenient studying of the bone landmarks. CONCLUSIONS: With the knowledge of bone landmarks, investigators would be able to attain more accurate measurements between skin landmarks.

New mesh-type phantoms and their dosimetric applications, including emergencies.

Committee 2 of the International Commission on Radiological Protection (ICRP) has constructed mesh-type adult reference computational phantoms by converting the voxel-type ICRP Publication 110 adult reference computational phantoms to a high-quality mesh format, and adding those tissues that were below the image resolution of the voxel phantoms and therefore not included in the Publication 110 phantoms. The new mesh phantoms include all the necessary source and target tissues for effective dose calculations, including the 8-40-µm-thick target layers of the alimentary and respiratory tract organs, thereby obviating the need for supplemental organ-specific stylised models (e.g. respiratory airways, alimentary tract organ walls and stem cell layers, lens of the eye, and skin basal layer). To see the impact of the new mesh-type reference phantoms, dose coefficients for some selected external and internal exposures were calculated and compared with the current reference values in ICRP Publications 116 and 133, which were calculated by employing the Publication 110 phantoms and the supplemental stylised models. The new mesh phantoms were also used to calculate dose coefficients for industrial radiography sources near the body, which can be used to estimate the organ doses of the worker who is accidentally exposed by an industrial radiography source; in these calculations, the mesh phantoms were deformed to reflect the size of the worker, and also to evaluate the effect of posture on dose coefficients.

The reference phantoms: voxel vs polygon.

The International Commission on Radiological Protection (ICRP) reference male and female adult phantoms, described in Publication 110, are voxel phantoms based on whole-body computed tomography scans of a male and a female patient, respectively. The voxel in-plane resolution and the slice thickness, of the order of a few millimetres, are insufficient for proper segmentation of smaller tissues such as the lens of the eye, the skin, and the walls of some organs. The calculated doses for these tissues therefore present some limitations, particularly for weakly penetrating radiation. Similarly, the Publication 110 phantoms cannot represent 8-40-µm-thick target regions in respiratory or alimentary tract organs. Separate stylised models have been used to represent these tissues for calculation of the ICRP reference dose coefficients (DCs). ICRP Committee 2 recently initiated a research project, the ultimate goal of which is to convert the Publication 110 phantoms to a high-quality polygon-mesh (PM) format, including all source and target regions, even those of the 8-40-µm-thick alimentary and respiratory tract organs. It is expected that the converted phantoms would lead to the same or very similar DCs as the Publication 110 reference phantoms for penetrating radiation and, at the same time, provide more accurate DCs for weakly penetrating radiation and small tissues. Additionally, the reference phantoms in the PM format would be easily deformable and, as such, could serve as a starting point to create phantoms of various postures for use, for example, in accidental dose calculations. This paper will discuss the current progress of the phantom conversion project and its significance for ICRP DC calculations.

Depigmentation therapy with Q-switched ruby laser after tanning in vitiligo universalis.

BACKGROUND: In vitiligo universalis, repigmentation therapy is seldom effective. Besides, bleaching cream which is often used in depigmentation therapy may lead to several serious complications. OBJECTIVE: Q-switched (QS) ruby laser can destroy melanosomes in melanocytes and keratinocytes by selective photothermolysis. METHODS: We have attempted to destroy melanocytes by using the QS ruby laser after tanning in a patient with extensive vitiligo. RESULTS: The patient had excellent results with no evidence of repigmentation after 1 year. CONCLUSION: Depigmentation therapy with QS ruby laser after tanning is an effective and safe way of removing remnants of normal pigmentation in patients with vitiligo universalis.

Increased and correlated nuclear factor-kappa B and Ku autoantigen activities are associated with development of multidrug resistance.

In this study, we investigated possible engagement of NF-kappaB and Ku autoantigen (Ku) activation in development of multidrug resistance (MDR) and circumvention of MDR by modulation of NF-kappaB and Ku. The NF-kappaB activity and NF-kappaB p65 subunit level were constitutively higher in MDR cells than in drug-sensitive parental cells. Interestingly, a faster running NF-kappaB DNA binding complex was identified as Ku, a DNA damage sensor and a key double strand break repair protein, and was positively correlated with the NF-kappaB activity in MDR cells and Ku- or both subunits of NF-kappaB-transfected cells. Also both NF-kappaB and Ku activities were activated or inhibited by treatment with etoposide (VP-16) or MG-132 (a proteasome inhibitor), respectively. Furthermore, PKA inhibitor suppressed markedly the constitutive and drug-induced activities of NF-kappaB and Ku in MDR cells and subsequently potentiated the cytotoxic activity of anticancer drugs. Our results proposed that the NF-kappaB and Ku activation could be one of multi-factorial MDR mechanism, and PKA inhibitor, likely via inhibition of NF-kappaB and Ku activities, could enhance the effectiveness of anticancer drugs against MDR cells with high activities of NF-kappaB and Ku.

Calciphylaxis in a patient with end-stage renal disease.

Calciphylaxis is a rare and life-threatening condition of progressive cutaneous necrosis secondary to small and medium-sized vessel calcification. It is seen almost exclusively in patients with end-stage renal disease and secondary hyperparathyroidism. We experienced a case of 67-year-old man with calciphylaxis that manifested with characteristic skin lesions, pathologic findings, and laboratory changes. His skin lesions began as painful erythematous patches and subsequently progressed to necrotic ulcers with eschars on the distal aspect of the extremities. Pathologically, calcification was found in small and medium-sized blood vessels in the deep dermis and subcutaneous tissue. His serum calcium was 9.5 mg/dL, phosphorus was 7.8 mg/dL, and nPTH was 99.9 pg/mL. The patient had been treated with surgical debridement and other supportive treatment. However, he eventually underwent an amputation below the right knee and died from sepsis.

Extracellular signal-regulated kinase/90-KDA ribosomal S6 kinase/nuclear factor-kappa B pathway mediates phorbol 12-myristate 13-acetate-induced megakaryocytic differentiation of K562 cells.

Two signaling pathways, the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK)-dependent pathway and the nuclear factor-kappaB (NF-kappaB)-dependent pathway, have been known to mediate megakaryocytic differentiation of K562 cells induced by phorbol 12-myristate 13-acetate (PMA). In this study, we examined whether 90-kDa ribosomal S6 kinase (RSK), known as a substrate of ERK/MAPK and a signal-inducible IkappaBalpha kinase, would link two pathways during the differentiation. RSK1 was activated in a time- and dose-dependent manner during the PMA-induced differentiation. Overexpression of wild-type or dominant inhibitory mutant (D205N) of RSK1 enhanced or suppressed PMA-stimulated NF-kappaB activation and megakaryocytic differentiation as shown by morphology, nonspecific esterase activity, and expression of the CD41 megakaryocytic marker, respectively. In addition, overexpression of the dominant inhibitory mutant (S32A/S36A) of IkappaBalpha inhibited PMA-stimulated and RSK1-enhanced megakaryocytic differentiation, indicating that NF-kappaB mediates a signal for megakaryocytic differentiation downstream of RSK1. PMA-stimulated activation of ERK/MAPK, RSK1, and NF-kappaB and the PMA-induced megakaryocytic differentiation were prevented by pretreatment with PD98059, a specific inhibitor of the mitogen-activated ERK kinase (MEK). Therefore, these results demonstrate that the sequential ERK/RSK1/NF-kappaB pathway mediates PMA-stimulated megakaryocytic differentiation of K562 cells.

Antiapoptotic role of NF-kappaB in the auto-oxidized dopamine-induced apoptosis of PC12 cells.

Current concepts of the pathogenesis of Parkinson's disease (PD) center on the formation of reactive oxygen species (ROS), and dopamine has been considered to be a major source of ROS. Recently, it has been shown in a postmortem study that nuclear translocation of nuclear factor-kappa B (NF-kappaB) was observed in dopaminergic neurons of patient with PD. However, its role is not known. The present study examined the possible role of NF-kappaB in ODA (auto-oxidized dopamine)-induced apoptosis to understand the process of PD. Using the electrophoretic mobility shift assay, it was found that ODA activated the DNA binding activity of NF-kappaB. Suppression of the transcriptional activity of NF-kappaB in PC12 cells by overexpression of a wild-type and a dominant negative mutant form (S32A/S36A) of inhibitor kappa B (IkappaB)-alpha led to increase of apoptotic cell death induced by treatment of ODA. In addition, overexpression of NF-kappaB in PC12 cells blocked ODA-induced cell death. However, JNK/SAPK activities, which mediate various stress signals, were similar among the parental, NF-kappaB- or dominant negative mutant IkappaB alpha-transfected cells. Therefore, these results suggest that activation of NF-kappaB during ODA-induced apoptosis may have a counteracting activity against the signals mediating apoptotic cell death and thereby delay the process of Parkinson's disease.

Potentiation of chemosensitivity in multidrug-resistant human leukemia CEM cells by inhibition of DNA-dependent protein kinase using wortmannin.

DNA-dependent protein kinase (DNA-PK) is activated by DNA strand breaks and participates in DNA repair. Its regulatory subunit, Ku autoantigen, binds to DNA and recruits the catalytic subunit (DNA-PKcs). We show here a new role of DNA-PK in the development of multidrug resistance (MDR). The Ku-DNA binding activity, the levels of Ku70/Ku80 and DNA-PKcs in MDR variants, CEM/VLB(10-2), CEM/VLB(55-8) and CEM/VLB100 were higher than those in their parental drug-sensitive CEM cells in a drug resistance-dependent fashion. Also, CEM/VLB100 cells showed about 3-fold increase of DNA-PK enzyme activity as compared with CEM cells. Similar results were observed in another MDR cell line, FM3A/M mouse mammary carcinoma cells. Moreover, we observed that CEM/VLB100 cells were about 11-fold sensitive to wortmannin, which inhibits DNA-PK, compared with the CEM cells, and sensitized the MDR cells when combined with either bleomycin or vincristine, but have a little effect on CEM cells. Wortmannin was shown to inhibit DNA-PK and Ku-DNA binding activity in CEM/VLB100 cells dose dependently but had a little or no effect on their parental cells. Our results suggested that enhanced expression of DNA-PK participates in the development of MDR, and the use of DNA-PK inhibitors such as wortmannin is likely to improve the effectiveness of anticancer drugs and thus could partially overcome drug resistance in MDR cells, through its ability to inhibit Ku/DNA-PK activity.

Purification of a 68-kDa cysteine proteinase from crude extract of Pneumocystis carinii.

The present study intended to verify activities of cysteine proteinase of Pneumocystis carinii from rats and to purify the enzyme. In order to exclude the contamination of host-derived enzymes, concentrates of P. carinii was primarily treated with a mixture of proteinase inhibitors before lysis of P. carinii. A 68-kDa cysteine proteinase was finally purified from the crude extract of P. carinii by 4 sequential chromatographic methods. The enzyme showed an optimal activity at pH 5.5 in 0.1 M sodium acetate, and its activity was specifically inhibited by L-trans-epoxy-succinylleucylamido (4-guanidino) butane (E-64) and iodoacetic acid, suggesting that the enzyme is a cysteine proteinase. The 68-kDa proteinase weakly digested macromolecules such as collagen, hemoglobin and fibronectin. The present study demonstrated the activity of cysteine proteinase at the 68-kDa band of P. carinii, and purified and characterized the molecule.

Genetic heterogeneity of Pneumocystis carinii from rats of several regions and strains.

Pneumocystis carinii is a major opportunistic pathogen which has been found in the lungs of a wide variety of mammalian host species, and the fact suggests the possibility of intraspecific variation. Until now, P. carinii from different mammalian species are differentiated as subspecies, and the rats are known to be infected by two subspecies. The present study investigated genetic heterogeneity of P. carinii isolates from two strains of rats in Korea and China by molecular karyotyping, RFLP and sequencing analysis. Karyotypes of P. carinii were grouped into three, two from two strains of rats in Korea and one from rats in China. However RFLP of PCR product of ribosomal and MSG gene of the P. carinii isolates showed same pattern. The sequence homology rates of alpha-tubulin DNA of the P. carinii isolates were 96% in Seoul Wistar rats, 93% in Seoul Sprague-Dawley rats, and 85% in Chinese Sprague-Dawley rats. The present finding confirmed that P. carinii from rats in Korea are grouped into two karyotype strains which are different from that of P. carinii from rats in China. The Chinese isolate shows a little different sequences of alpha-tubulin DNA.

Partial characterization of a 17 kDa protein of Clonorchis sinensis.

A 17 kDa protein from Clonorchis sinensis adults was purified by a procedure including Sephacryl S-200 HR gel filtration and Q-Sepharose anion exchange chromatography. The protein was proved to be a cysteine protease as it showed hydrolytic activity toward Cbz-Phe-Arg-AMC in the presence of dithiothreitol and was inhibited by specific inhibitors such as iodoacetic acid or trans epoxy-succinly-L-leucyl-amido(4-guanidino) butane. The polyclonal antibody raised against the protein reacted to 17 kDa proteins of trematodes such as Paragonimus westermani, Fasciola hepatica, Opisthorchis viverrini, Gymnophalloides seoi, and Metagonimus yokogawai. The antibody recognized the 17 kDa and 16 kDa cysteine proteases purified from C. sinensis, P. westermani, and G. seoi as well. These results suggest that the 17 kDa protein may be a cysteine protease commonly present in trematodes.

The inhibition of ERK/MAPK not the activation of JNK/SAPK is primarily required to induce apoptosis in chronic myelogenous leukemic K562 cells.

In this study, the downstream signaling of Bcr-Abl tyrosine kinase responsible for apoptosis resistance was investigated. DNA fragmentation, a hallmark of apoptosis, was observed after 2 days of herbimycin A treatment with a peak on 3 day. During the apoptosis induced by the treatment of herbimycin A, stress-activated protein kinase (SAPK) and p38 kinase were activated time- and dose-dependently, while extracellular signal-regulated kinase (ERK) was inhibited. However, apoptosis was induced by the treatment of PD98059, a specific inhibitor of MEK (MAPK or ERK kinase), not by the treatment of sorbitol, a strong activator of SAPK and p38 kinase. Although K562 cells were very resistant to sorbitol-induced apoptosis, DNA fragmentation was induced rapidly in Jurkat, HL-60 and U937 cells after exposure to sorbitol, despite that these apoptosis-sensitive cells have similar or lower activities of JNK/SAPK and p38 kinase compared with K562 cells after treatment of sorbitol. K562 cells had a much higher basal activity of ERK/MAPK than other apoptosis-sensitive cell lines, which were very susceptible to apoptosis induced by low dose of PD98059 compared with K562 cells. In HL-60 cells, sorbitol-induced apoptosis was prevented by the treatment of phorbol myristate 13-acetate (PMA), which activates the ERK/MAPK pathway, and this was blocked by PD98059. From these results, it could be suggested that the inhibition of ERK/MAPK not the activation of JNK/SAPK is primarily required to induce apoptosis in K562 cells.

Downregulation of JNK/SAPK activity is associated with the cross-resistance to P-glycoprotein-unrelated drugs in multidrug-resistant FM3A/M cells overexpressing P-glycoprotein.

In the present study, cross-drug resistance in multidrug-resistant (MDR) cells, which overexpress P-glycoprotein (Pgp), a mdr1 gene product, against Pgp-unrelated drugs, and its relevance to c-Jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK) activity were examined. The multidrug-resistant FM3A/M cells overexpressing Pgp were resistant to apoptotic cell death induced either by Pgp-related drugs including vincristine and vinblastine, which are pumped out by Pgp, or by the Pgp-unrelated drugs including 5'-fluorouracil (5-FU) and bleomycin, which are not targets for Pgp, compared with the parental FM3A cells. Verapamil reversed the resistance of FM3A/M cells to apoptosis induced by the Pgp-related drugs but not that induced by the Pgp-unrelated drugs. Interestingly, FM3A/M cells have shown significantly lower basal and drug-stimulated JNK/SAPK activities than FM3A cells. After transfection with pEBG-SEK or pEBG-SAPK constructs, FM3A/M cells recovered the basal and Pgp-unrelated drug-stimulated activities of JNK/SAPK and the susceptibility to Pgp-unrelated drug-induced apoptotic cell death comparable to those of FM3A cells. Furthermore, FM3A cells became resistant to apoptotic cell death induced by vincristine and 5-FU after transfection with pEBG-SEK(K --> R), a dominant negative inhibitory mutant of SEK. These results suggest that downregulation of JNK/SAPK activity appears to confer on Pgp-associated FM3A/M cells a cross-resistance to Pgp-unrelated drugs.

Ku autoantigen affects the susceptibility to anticancer drugs.

The Ku70/80 autoantigens (Ku) are the DNA-binding components of a DNA-dependent protein kinase (PK) involved in DNA double strand breaks repairing a V(D)J recombination. Because apoptosis is associated with DNA fragmentation and, consequently, creation of double strand breaks, and a variety of DNA-damaging drugs kill tumor cells by apoptosis, we tested the impact of Ku deficiency on the sensitivity of anticancer drugs. Ku-null mutant cell lines Ku70-/- and Ku80-/- were highly sensitive to anticancer drugs, compared with their wild-type cells. Ku-deficient cells were more sensitive to bleomycin-induced DNA fragmentation and exhibited a higher level of c-jun NH2-kinase/stress-activated PK activity than wild-type cells, whereas R7080-6 cells overexpressing both human Ku70 and Ku80 were resistant to bleomycin-induced apoptosis and exhibited a lower level of c-jun NH2-kinase/stress-activated PK activity. The Ku-protein level and Ku DNA binding activity were decreased after treatment with bleomycin, adriamycin, or vincristine, and the decreases were blocked by the treatment of z-DEVD-fmk, a specific inhibitor of caspase-3, suggesting that loss of Ku DNA binding is, in part, due to a caspase-mediated decrease in Ku protein levels. By contrast, HSF1 DNA-binding activity was increased by the treatment of these anticancer drugs and, subsequently, mitochondrial heat shock protein HSP75 was specifically induced. Our data suggest that Ku can affect the susceptibility to anticancer drug-induced apoptosis.

Involvement of c-Jun NH(2)-terminal kinase pathway in differential regulation of heat shock proteins by anticancer drugs.

In the present study, we examined the modulation of heat shock factor 1 (HSF1) activity and expression of heat shock proteins (HSPs) after exposure to anticancer drugs. Anticancer drugs induced HSF1 DNA-binding activity, and this was followed by an increase of mitochondrial HSP75 and HSP60 levels and concurrent decrease of cytoplasmic HSP70 levels. Unlike heat shock-induced full phosphorylation, HSF1 was partially phosphorylated after exposure to vincristine, and this result was tightly correlated with the kinetics of JNK/SAPK activation, and up-regulation of mitochondrial HSP75 level and concurrent down-regulation of HSP70. Furthermore, the dominant-negative mutant of SEK1 blocked the phosphorylation of HSF1 and up-regulation of mitochondrial HSP75 in response to vincristine or vinblastine. These data suggest that anticancer drugs regulate the HSF1 transcriptional activity differently from heat shock, and JNK/SAPK pathway appears to be involved in anticancer drug-induced HSF1 phosphorylation and consequently differential regulation of mitochondrial HSP75 and HSP60 and cytoplasmic HSP70.

Role of Ras/ERK-dependent pathway in the erythroid differentiation of K562 cells.

The chronic myelogenous leukemic K562 cell line carrying Bcr-Abl tyrosine kinase is considered as pluripotent hematopoietic progenitor cells expressing markers for erythroid, granulocytic, monocytic, and megakaryocytic lineages. Here we investigated the signaling modulations required for induction of erythroid differentiation of K562 cells. When the K562 cells were treated with herbimycin A (an inhibitor of protein tyrosine kinase), ras antisense oligonucleotide, and PD98059 (a specific inhibitor of MEK), inhibition of ERK/MAPK activity and cell growth, and induction of erythroid differentiation were observed. The ras mutant, pZIPRas61leu-transfected cells, K562-Ras61leu, have shown a markedly decreased cell proliferation rate with approximately 2-fold doubling time, compared with the parental K562 cells, and about 60% of these cells have shown the phenotype of erythroid differentiation. In addition, herbimycin A inhibited the growth rate and increased the erythroid differentiation, but did not affect the elevated activity of ERK/MAPK in the K562-Ras61leu cells. On the other hand, effects of PD98059 on the growth and differentiation of K562-Ras61leu cells were biphasic. At low concentration of PD98059, which inhibited the elevated activity of ERK/MAPK to the level of parental cells, the growth rate increased and the erythroid differentiation decreased slightly, and at high concentration of PD98059, which inhibited the elevated activity of ERK/MAPK below that of the parental cells, the growth rate turned down and the erythroid differentiation was restored to the untreated control level. Taken together, these results suggest that an appropriate activity of ERK/MAPK is required to maintain the rapid growth and transformed phenotype of K562 cells.

Activation of c-jun N-terminal kinase/stress-activated protein kinase and the decreased ratio of Bcl-2 to Bax are associated with the auto-oxidized dopamine-induced apoptosis in PC12 cells.

Current concepts of the pathogenesis of Parkinson's disease center on the formation of reactive oxygen species (ROS). Dopamine is one of the major sources of ROS. In this study, the molecular events during the dopamine-induced apoptosis in PC-12 cells were studied using auto-oxidized dopamine. Auto-oxidized-dopamine induced DNA fragmentation and activation of c-jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK) faster and stronger than dopamine. Furthermore, N-acetylcysteine, an antioxidant, prevented the auto-oxidized dopamine-induced JNK/SAPK activation and DNA fragmentation. Meanwhile, Bcl-2 started to decrease after onset of apoptosis, and Bax was increased up to beginning of apoptosis, and thereafter decreased. Therefore, these results suggested that activation of JNK/SAPK and the decreased ratio of antiapoptotic Bcl-2 to proapoptotic Bax appear to be associated with the dopamine-induced apoptosis.

Suppression of multidrug resistance via inhibition of heat shock factor by quercetin in MDR cells.

MDR1 promoter has been shown to contain heat shock elements (HSE), and it has been reported that FM3A/M and P388/M MDR cells show a constitutively activated heat shock factor (HSF), suggesting that HSF might be an important target for reversing the multidrug resistance. Therefore, it was examined whether quercetin, which has been shown to interfere with the formation of the complex between HSE and HSF, and to downregulate the level of HSF1, can sensitize MDR cells against anticancer drugs by inhibition of HSF DNA-binding activity. In this study, quercetin appeared to inhibit the constitutive HSF DNA-binding activity and the sodium arsenite-induced HSF DNA-binding activity in the MDR cells. The basal and sodium arsenite-induced MDRCAT activities were remarkably suppressed by the treatment of quercetin. These results were well consistent with the finding that the treatment of quercetin decreased the expression level of P-gp, MDR1 gene product, in dose-dependent manner, and markedly increased the sensitivity of MDR cells to vincristine or vinblastine. These results suggest that quercetin can decrease the expression of P-gp via inhibition of HSF DNA-binding activity, and might be useful as a chemosensitizer in MDR cells.