Central nervous system (CNS) tumors in the first six months of life: the Children's Hospital Los Angeles experience, 1979-2005

BACKGROUND

The authors report the experience at the Children's Hospital Los Angeles with brain tumors diagnosed before 6 months of age, describing the characteristics of the patients, their tumors, treatment strategies, and prognostic factors.

METHODS

Thirty-three children who were identified between 1979 and 2005 were included. Twelve were female (36%). There were 11 gliomas, 9 choroid plexus tumors, 8 medulloblastomas and supratentorial primitive neuroectodermal tumors (PNET), 2 atypical teratoid/rhabdoid tumors (ATRT), and 1 each of ependymoma, craniopharyngioma, and immature teratoma. Locations of primary tumors included 21 supratentorial (64%) and 7 posterior fossa, and 5 tumors involved both compartments. The treatment strategies included 5 patients with biopsy only, 18 less than gross total resections (<GTRx), and 9 GTRx. Fourteen children (42%) received chemotherapy. Three patients (9%) received irradiation, 1 at initial diagnosis and 2 at relapse. Nine patients (27%) demonstrated metastases, 6 at diagnosis and 3 at relapse.

RESULTS

The Kaplan Meier analysis of event-free survival (EFS) and overall survival (OS) for all patients is 21 +/- 9% and 35 +/- 9% at 5 years. For the glioma patients, the 4-year OS is 48 +/- 17%, while the 5-year OS for the medulloblastoma/PNET/ATRT patients is 12 +/- 11% (p = .39). The 5-year OS for children achieving a GTRx is 64 +/- 21% and for those with <GTRx is 27 +/- 10% (p = .08).

Effects of neoadjuvant radiochemotherapy on pathological staging and prognosis for locally advanced esophageal squamous cell carcinoma

The role of neoadjuvant therapy in the treatment of locally advanced esophageal carcinoma still remains controversial. The aim of this study was to evaluate the effects of neoadjuvant radiochemotherapy on pathological staging and prognosis in the patients with locally advanced esophageal squamous cell carcinoma. Between January 1991 and December 2000, 473 patients with advanced esophageal carcinoma diagnosed by endoscopic biopsy underwent surgical resection in our center. With informed consent, they were randomized into four groups: neoadjuvant chemotherapy, neoadjuvant radiotherapy, neoadjuvant radiochemotherapy, and surgery alone (control group). The preoperative computed tomography staging criteria were the following: Stage I, the tumor limited to the esophageal lumen or the thickness of the esophageal wall varied between 3-5 mm; Stage II, the thickness exceeds 5 mm but no invasion to the mediastinum or distant metastasis; Stage III, the tumor invades adjacent mediastinal structure; and Stage IV, there is distant metastasis. The tumor resection rate, pathological stage, treatment-related complication, and survival among groups were compared. The radical resection rate for the patients in radiotherapy and radiochemotherapy groups was increased in comparison with the control group (P < 0.05). Their pathological stage after esophagectomy was regressed significantly than that of the control group (50.85%, 55.08% vs. 0%, P < 0.05). The adjuvant chemotherapy group did show significant improvement on resection rate and pathological staging compared with the control group. The treatment-related complication in the three neoadjuvant groups had no significant difference from that of the control group (P > 0.05). The 3-year survival rate of radiotherapy and radiochemotherapy groups were significantly higher than that of the control group (69.49%, 73.73% vs. 53.38%, P < 0.05). The 5-year survival rate of radiochemotherapy group was higher than that of the radiotherapy group although did not show a statistical difference (P > 0.05). Rational application of neoadjuvant radiochemotherapy seems to provide a modest benefit in radical resection and survival in patients with locally advanced esophageal carcinoma.

Greater osteoporosis educational outreach is desirable among Chinese immigrants in Chinatown, Chicago

Osteoporosis beliefs were assessed in immigrant Chinese women in Chinatown, Chicago. Results from a survey utilizing the Osteoporosis Health Belief Scale showed that women expressed concern about osteoporosis but lacked both knowledge of preventive care and health motivation.

INTRODUCTION

The objective of this study was to assess osteoporosis beliefs in immigrant Chinese women in Chinatown, Chicago.

METHODS

In a community-based health fair, osteoporosis knowledge and self-efficacy among postmenopausal Chinese immigrants were assessed using the translated Osteoporosis Health Belief Scale. Bone mineral density (BMD) was assessed with calcaneal ultrasound.

RESULTS

The study population included 94 women with mean age of 51 +/- 9 years, mean length of residence in the United States of 9 +/- 7 years, and 73% (n = 76) of whom were recent immigrants. Women expressed concern about the seriousness of osteoporosis and their relative susceptibility to osteoporosis. In particular, women with a prior fracture reported higher seriousness to osteoporosis. Nonetheless, women exhibited low health motivation and low awareness of the benefits of calcium and exercise. Bone densitometry results corresponded to a T score of -1.2 +/- 1.5. Multiple regression analysis revealed that a younger age and longer length of residence in the USA were associated with higher BMD.

CONCLUSION

Chinese immigrant women in Chicago exhibit concern regarding osteoporosis, but are unaware of the benefits of calcium and exercise, and exhibit low health motivation. Chinese women in Chinatown lack necessary knowledge about osteoporosis to develop adequate self-efficacy. Public health initiatives should be undertaken among recent immigrant Chinese women.

A phase I trial of intravenous therapy with tumor suppressor FUS1-nanoparticles for recurrent/metastatic lung cancer

e19065

Background: The tumor suppressor gene FUS1 is frequently inactivated early in lung cancer development. FUS1 mediates apoptosis in cancer cells but not normal cells through its interaction with Apaf1. DOTAP:cholesterol nanoparticles encapsulating a FUS1 expression plasmid showed selective uptake by cancer cells and activity in mouse xenograft metastatic lung cancer models. Methods: Patients with recurrent/metastatic lung cancer previously treated with platinum-based chemotherapy were treated with escalating doses of intravenous DOTAP:cholesterol FUS1 nanoparticles. Nanoparticle-DNA complexes were manufactured in GMP facilities to meet specifications of OD400, size, appearance, and transfection efficiency. Results: Patients have received doses ranging from 0.01–0.09 mg/kg at 3 week intervals. To date 23 patients have been entered on study at 6 dose levels, with 21 patients currently evaluable for the primary endpoint of cycle 1 toxicity. 70% of subjects had received 2 or more prior chemotherapy regimens. Among 4 patients treated without premedications, all 4 developed grade 2 or higher fevers within 24 hours of treatment. Among the 17 patients premedicated with dexamethasone and diphenhydramine, 4 developed grade 1 fever. There have been no other grade 2 or higher drug-related toxicities. Four patients received only one dose because of rapidly progressing disease at a site requiring local treatment. Fifteen patients received two or more doses and are evaluable for response, with 4 patients achieving stable disease and 11 patients progressing. Median survival time for all patients is 10.3 months. A maximum tolerated dose (MTD) has not been reached. Pre and 24 hour posttreatment tumor biopsies were obtained from 4 patients. A quantitative real time reverse transcriptase PCR (RT-PCR) analysis using a plasmid FUS1 sequence-specific probe have been performed on 3 paired-samples blinded to time of biopsy. A high level of plasmid FUS1 expression was detected in all 3 posttreatment samples but not in three pretreatment samples and negative controls by RT-PCR. Conclusions: DOTAP:cholesterol FUS1 nanoparticles can be safely administered intravenously in lung cancer patients with demonstrable gene expression in posttreatement tumor biopsies.

[Table: see text]

Engineering tissue from human embryonic stem cells

Recent advances in human embryonic stem cell (hESC) biology now offer an alternative cell source for tissue engineers, as these cells are capable of proliferating indefinitely and differentiating to many clinically relevant cell types. Novel culture methods capable of exerting spatial and temporal control over the stem cell microenvironment allow for more efficient expansion of hESCs, and significant advances have been made toward improving our understanding of the biophysical and biochemical cues that direct stem cell fate choices. Effective production of lineage specific progenitors or terminally differentiated cells enables researchers to incorporate hESC derivatives into engineered tissue constructs. Here, we describe current efforts using hESCs as a cell source for tissue engineering applications, highlighting potential advantages of hESCs over current practices as well as challenges which must be overcome.

A mitochondrial DNA variant at position 16189 is associated with type 2 diabetes mellitus in Asians

AIMS/HYPOTHESIS

This multinational study was conducted to investigate the association between a mitochondrial DNA (mtDNA) T16189C polymorphism and type 2 diabetes in Asians. The mtDNA 16189C variant has been reported to be associated with insulin resistance and type 2 diabetes. However, a recent meta-analysis concluded that it is negatively associated with type 2 diabetes in Europids. Since the phenotype of an mtDNA mutant may be influenced by environmental factors and ethnic differences in the nuclear and mitochondrial genomes, we investigated the association between the 16189C variant and type 2 diabetes in Asians.

METHODS

The presence of the mtDNA 16189C variant was determined in 2,469 patients with type 2 diabetes and 1,205 non-diabetic individuals from Korea, Japan, Taiwan, Hong Kong and China. An additional meta-analysis including previously published Asian studies was performed. Since mtDNA nucleotide position 16189 is very close to the mtDNA origin of replication, we performed DNA-linked affinity chromatography and reverse-phase liquid chromatography/tandem mass spectrometry and chromatin immunoprecipitation to identify protein bound to the 16189 region.

RESULTS

Analysis of participants from five Asian countries confirmed the association between the 16189C variant and type 2 diabetes [odds ratio (OR) 1.256, 95% CI 1.08-1.46, p=0.003]. Inclusion of data from three previously published Asian studies (type 2 diabetes n=3,283, controls n=2,176) in a meta-analysis showed similar results (OR 1.335, 95% CI 1.18-1.51, p=0.000003). Mitochondrial single-stranded DNA-binding protein (mtSSB) was identified as a candidate protein bound to the 16189 region. Chromatin immunoprecipitation in cybrid cells showed that mtSSB has a lower binding affinity for the 16189C variant than the wild-type sequence.

CONCLUSIONS/INTERPRETATION

The mtDNA 16189C variant is associated with an increased risk of type 2 diabetes in Asians.

Genetic analysis of four porcine avian influenza viruses isolated from Shandong, China

A Bayesian phylogenetic analysis of eight separate gene segments indicated A/Swine/Shandong/2/2003 (H5N1), A/Swine/Shandong/na/2003 (H9N2), A/Swine/Shandong/nb/2003 (H9N2) and A/Swine/Shandong/nc/2005 (H9N2) probably represent two multiple reassortant lineages, that had not been described before, with genes coming from H5N1, H9N2 and other lineages from poultry in Asia. Amino acid motifs within the haemagglutinin sequence of A/Swine/Shandong/nb/2003 suggested it may be able to infect people, whereas the sequences of the other three isolates suggested they would not have had that capability. Our analysis emphasizes the need for a comprehensive study of the interactions between H5N1 and H9N2 viruses in Asia that includes sequencing and phylogenetic investigation.

Enhancement of antitumor activity of cisplatin in human lung cancer cells by tumor suppressor FUS1

FUS1 is a novel tumor suppressor gene located in the human chromosome 3p21.3 region. We previously showed that restoration of FUS1 function in 3p21.3-deficient human non-small-cell lung cancer (NSCLC) cells significantly inhibited tumor cell growth in vitro and in vivo. In this study, we evaluated the combined effects of the tumor suppressor FUS1 and the chemotherapeutic drug cisplatin on tumor cell growth and apoptosis induction in NSCLC cells, and explored the molecular mechanism of their mutual action. Exogenous expression of FUS1 by nanoparticle-mediated gene transfer sensitized the response of NSCLC cells to cisplatin, resulting in a 4- to 6-fold increase in tumor-suppressing activity. A systemic treatment with a combination of FUS1-nanoparticles and cisplatin in a human H322 lung cancer orthotopic xenograft mouse model dramatically enhanced the therapeutic efficacy of cisplatin. We also found that the FUS1-enhanced chemosensitivity is associated with the downregulation of MDM2, accumulation of p53 and activation of the Apaf-1-dependent apoptosis pathway. Our results demonstrated an important role of FUS1 in modulating chemosensitivity of lung cancer cells, and suggested that a proper combination of molecular therapeutics such as the proapoptotic tumor suppressor FUS1 and the conventional chemotherapeutic drugs such as cisplatin may be an efficient treatment strategy for human lung cancer.

Identification of central nervous system sites involved in the water diuresis response elicited by central microinjection of nociceptin/ Orphanin FQ in conscious rats via c-Fos and inducible cAMP early repressor immunocytochemistry

Intracerebroventricular (i.c.v.) administration of the opioid-like peptide, nociceptin/Orphanin (nociceptin), in conscious rats produces diuretic and antinatriuretic effects. The present study utilised changes in Fos and inducible cAMP early repressor (ICER) immunocytochemistry expression to examine the central nervous (CNS) sites activated or inhibited, respectively, by central administration of nociceptin. Urine samples were collected during control (15 min) and after i.c.v. vehicle (5 microl, n = 12) or nociceptin (10 microg/5 microl; n = 12). Four additional urine samples (15-min) were collected after the i.c.v. injection. The brain was processed for Fos using a commercially available antibody (Oncogene AB-5) and for ICER using a polyclonal anti-ICER antibody raised in rabbits. In vehicle-injected conscious rats, renal excretion of water or sodium was not altered. However, nociceptin produced a rapid and marked increase in urine flow (V) and a decrease in urinary sodium excretion rate. In addition, i.c.v. nociceptin produced a significant increase in Fos staining in the dorsomedial nucleus of the hypothalamus, the perinuclear zone of the supraoptic nucleus, the organum vasculosum of the lamina terminalis (OVLT), the lateral preoptic area and the lateral hypothalamic area compared to control. By contrast, Fos expression decreased in the area postrema and locus coeruleus compared to controls. Furthermore, ICER staining was significantly increased in the perinuclear zone of the supraoptic nucleus, supraoptic nucleus, median preoptic nucleus, OVLT, medial preoptic area, central nucleus of the amygdala, and medial nucleus of the solitary tract. Together, central opioid receptor-like type 1 activation in these CNS regions may participate in the neural pathways involved in the diuretic and antinatriuretic effects of nociceptin.

Outcome of children less than three years old at diagnosis with non-metastatic medulloblastoma treated with chemotherapy on the “Head Start” I and II protocols: Final report

9507

Background: The use of dose-intensive chemotherapy with autologous hematopoietic cell rescue (AuHCR) is a potentially curative approach to the management of infants and young children with non-metastatic (M-0) medulloblastoma, with the additional benefit of avoiding the late effects of irradiation. We report the results of the “Head Start” I (1991 to 1997) and “Head Start” II (1997 to 2002) clinical trials, using this approach, to treat children with M-0 medulloblastoma, who were less than three years of age at diagnosis. Methods: Twenty one children were enrolled on these two serial studies. After surgery, patients received a uniform induction chemotherapy regimen consisting of five cycles of vincristine, cisplatin, cyclophosphamide and etoposide. Following completion of induction, all patients underwent myeloablative consolidation chemotherapy using carboplatin, thiotepa and etoposide followed by AuHCR, and did not receive irradiation. Irradiation was used only at relapse. Quality of life (QoL) and social and emotional behavior were evaluated on “Head Start” I, and cognitive functioning was evaluated on “Head Start” II survivors. Results: The five-year event-free (EFS) and overall survival (OS) rates (±SE) for all patients, patients with gross total resection, and patients with residual tumor were 52 ± 11% and 70 ± 10%, 64 ± 13% and 79 ± 17%, and 29 ± 17% and 57 ± 19%, respectively. The five-year EFS and OS (±SE) for patients with desmoplastic and classical medulloblastoma were 67 ± 16% and 78 ± 14%, and 42 ± 14 and 67 ± 14%, respectively. Young age (<2 years versus 2 to 3 years) at diagnosis did not appear to impact adversely upon outcome. There were four treatment related deaths. A majority of survivors (71%) avoided irradiation altogether. Neuropsychological functioning in children surviving without irradiation was well within the normal range for most patients. Conclusions: The strategy of brief intensive chemotherapy without irradiation for young children with M-0 medulloblastoma has eliminated the need for craniospinal irradiation in over half (52%) of the patients, with preservation of QoL and cognitive functioning in the majority.

No significant financial relationships to disclose.

Oncogenic activation of c-Abl in non-small cell lung cancer cells lacking FUS1 expression: inhibition of c-Abl by the tumor suppressor gene product Fus1

In lung cancer, frequent loss of one allele of chromosome 3p is seen in both small cell lung cancer and non-small cell lung cancer (NSCLC), providing evidence of tumor suppressor genes (TSGs) in this chromosomal region. The mechanism of Fus1 tumor suppressor activity is unknown. We have found that a Fus1 peptide inhibits the Abl tyrosine kinase in vitro (IC(50) 35 microM). The inhibitory Fus1 sequence was derived from a region that was deleted in a mutant FUS1 gene (FUS1 (1-80)) detected in some lung cancer cell lines. Importantly, a stearic acid-modified form of this peptide was required for the inhibition, but stearic acid alone was not inhibitory. Two NSCLC cell lines, which lack expression of wild-type Fus1, contain activated c-Abl. Forced expression of an inducible FUS1 cDNA in H1299 NSCLC cells decreased levels of activated c-Abl and inhibited its tyrosine kinase activity. Similarly, treatment of c-Abl immune complexes with the inhibitory Fus1 peptide also reduced the level of c-Abl in these immune complexes. The size and number of colonies of the NSCLC cell line, H1,299, in soft agar was strongly inhibited by the Abl kinase inhibitor imatinib mesylate. Co-expression of FUS1 and c-ABL in COS1 cells blocked activation of c-Abl tyrosine kinase. In contrast, co-expression of mutant FUS1 (1-80) with c-ABL had little inhibitory activity against c-Abl. These findings provide strong evidence that c-Abl is a possible target in NSCLC patients that have reduced expression of Fus1 in their tumor cells.

The reaction strategy of lower extremity muscles when slips occur to individuals with trans-femoral amputation

The aim of this study is to investigate the surface electromyography (sEMG) responses of lower extremity muscles for both healthy people and individuals with trans-femoral amputation (TFA), when slip events occur during level walking. Six male individuals with unilateral TFA and five healthy subjects participated in this study. Each subject was required to walk at a self-selected comfortable pace along a 5m plastic walkway, and to perform walking trials on dry and oily conditions respectively. The sEMG signals of muscles on legs and around waist were recorded in each trial and the normalized instantaneous muscle power (IMP) values were employed to quantify the response intensity. The IMP profiles of each muscle in oily-surface walking trials were compared quantitatively with that in dry-surface trials. There are three main findings in this study. (1) Different muscle reaction strategies are employed in slip events by the healthy persons and the individuals with TFA, respectively. Moreover, when the slip event occurs on the prosthetic leg and the intact leg of the individuals with TFA respectively, the muscle reaction strategies are also different. (2) The individuals with TFA face higher risks of fall than the healthy persons no mater slips occur on the prosthetic side or the intact side. (3) The hip muscles, especially the gluteus maximus (GMA) muscles, always enormously contribute to posture adjustment and balance recovery in slip events.

The statistical energy analysis of coupled sets of oscillators

The paper concerns the statistical energy analysis (SEA) of two conservatively coupled oscillators, sets of oscillators and continuous subsystems under broadband excitation. The oscillator properties are assumed to be random and ensemble averages found. Account is taken of the correlation between the coupling parameters and the oscillator energies. For coupled sets of oscillators or continuous subsystems, it is assumed that the coupling power between a pair of oscillators is proportional to the difference of either their actual energies or their ‘blocked’ energies, and expressions for the ensemble averages and coupling loss factors (CLFs) are found. Various observations are made, some of which differ from those that are commonly assumed within SEA. The coupling power and CLF are governed by two parameters: the ‘strength of connection’ and the ‘strength of coupling’. The CLF is proportional to damping at low damping and independent of damping in the high damping, weak coupling limit. Equipartition of energy does not occur as damping tends to zero, except for the case of two oscillators that have identical natural frequencies. While attention is focused on spring-coupled oscillators, similar results hold for more general forms of conservative coupling. The examples of two spring-coupled rods and two spring-coupled plates are considered. Conventional SEA and the coupled oscillator results are in good agreement for weak coupling but diverge for strong coupling. For strong coupling and weak connection, the coupled oscillator results agree well with an exact wave analysis and Monte Carlo simulations.

Genistein prevents thyroid hormone-dependent tail regression ofRana catesbeiana tadpoles by targetting protein kinase C and thyroid hormone receptor α

Thyroid hormone (TH)-regulated gene expression is mainly mediated by TH binding to nuclear thyroid hormone receptors (TRs). Despite extensive studies in mammalian cell lines that show that phosphorylation signaling pathways are important in TH action, little is known about their roles on TH signaling in vivo during development. Anuran metamorphosis is a postembryonic process that is absolutely dependent upon TH and tadpole tail resorption can be precociously induced by exogenous administration of 3,5,3'-triiodothyronine (T(3)). We demonstrate that genistein (a major isoflavone in soy products and tyrosine kinase inhibitor) and the PKC inhibitor (H7) prevent T(3)-induced regression of the Rana catesbeiana tadpole tail. T(3)-induced protein kinase C tyrosine phosphorylation and kinase activity are inhibited by genistein while T(3)-induced up-regulation of TRbeta mRNA, but not TRalpha mRNA, is significantly attenuated, most likely through inhibition of T(3)-dependent phosphorylation of the TRalpha protein. This phosphorylation may be modulated through PKC. These data demonstrate that T(3) signaling in the context of normal cells in vivo includes phosphorylation as an important factor in establishing T(3)-dependent tail regression during development.

Minimal step length necessary for recovery of forward balance loss with a single step

Although the boundary conditions necessary to trigger a step in reaction to a forward balance loss have been predicted in previous research, the relationship between minimal step length needed for balance recovery with this single step and the center of mass (COM) motion state (i.e., its position and velocity) remains unknown. The purpose of this paper was to present a theoretical framework within which the minimal step length needed for balance recovery can be estimated. We therefore developed a simplified four-segment sagittal model of human body stepping for balance recovery. The work-energy principle of the Newtonian mechanics was employed in the simulation to determine the amount of excess mechanical energy that can be absorbed as a function of step length and the corresponding eccentric joint work that can be generated in a single step. We found that an increase in initial forward velocity and a greater forward shift of the COM require a corresponding increase in the minimal step length needed for balance recovery. Furthermore, the minimal step length is also a function of the muscle strength at the ankle: the lower the muscle strength, the greater the minimal step length required. Our theoretical framework reduces the complexity associated with previous studies relying on forward dynamics and iterative optimization processes. This method may also be applied to study aspects of balance control such as the prevention of balance loss in the posterior or mediolateral direction.

Synergistic and selective inhibition of NSCLC cell growth via a caspase-independent cell death pathway by tumor suppressor 101F6 nanoparticles plus vitamin C in vitro and in vivo

13086

Background: 101F6 is a candidate tumor suppressor gene on chromosome 3p21.3, a site of allele loss and genomic alterations were frequently found in many human cancers. We previously showed that enforced expression of wt-101F6 by adenoviral virus significantly inhibited tumor cell growth in 3p21.3-deficient NSCLC cells in vitro and in vivo. How 101F6 exerts this effect is largely unknown. Using a computer-aided structural and functional modeling, we recently identified 101F6 as a member of cytochrome b-561 protein family, which is involved in the regeneration of vitamin C. We hypothesized that under normal physiologic conditions, 101F6 protects cells from oxidative damage by regenerating antioxidant vitamin C and that in 101F6-deficient tumor cells, exogenous 101F6 facilitates vitamin C-mediated cytotoxic H2O2 formation. Methods and Results: We examined endogenous 101F6 expression in human NSCLC cell lines and tissue samples. All normal lung bronchial epithelial cells and fibroblasts but few lung cancers expressed 101F6. We investigated the combined effect of 101F6 and vitamin C on the cell growth: a nanoparticle-mediated wt-101F6 gene transfer plus a sub-pharmacologic concentration of vitamin C synergistically inhibited 3p21.3-deficient NSCLC cell growth but did not affect normal cell growth. We also used a human NSCLC H322 orthotopic lung tumor xenograft mouse model to evaluate the therapeutic efficacy of systemic injection of 101F6 nanoparticles and intraperitoneal injection of vitamin C. The growth of lung tumors was synergistically inhibited by the combination treatment (p<0.001). Furthermore, exogenous 101F6 promoted intracellular vitamin C uptake, leading to the vitamin C-mediated accumulation of H2O2 in the tumor cells, and these two agents synergistically killed the cells through caspase-independent apoptosis and autophagy cell death pathways. Conclusions: The synergistic and selective antitumor effect of 101F6 nanoparticles plus vitamin C may offer a useful tool for lung cancer prevention and intervention. This abstract is supported by grants from NCI (SPORE P50CA70907) and DOD (TARGET, DAMD17002–1-0706).

No significant financial relationships to disclose.

Tracking quasi-stationary flow of weak fluorescent signals by adaptive multi-frame correlation

We have developed a novel cross-correlation technique to probe quasi-stationary flow of fluorescent signals in live cells at a spatial resolution that is close to single particle tracking. By correlating image blocks between pairs of consecutive frames and integrating their correlation scores over multiple frame pairs, uncertainty in identifying a globally significant maximum in the correlation score function has been greatly reduced as compared with conventional correlation-based tracking using the signal of only two consecutive frames. This approach proves robust and very effective in analysing images with a weak, noise-perturbed signal contrast where texture characteristics cannot be matched between only a pair of frames. It can also be applied to images that lack prominent features that could be utilized for particle tracking or feature-based template matching. Furthermore, owing to the integration of correlation scores over multiple frames, the method can handle signals with substantial frame-to-frame intensity variation where conventional correlation-based tracking fails. We tested the performance of the method by tracking polymer flow in actin and microtubule cytoskeleton structures labelled at various fluorophore densities providing imagery with a broad range of signal modulation and noise. In applications to fluorescent speckle microscopy (FSM), where the fluorophore density is sufficiently low to reveal patterns of discrete fluorescent marks referred to as speckles, we combined the multi-frame correlation approach proposed above with particle tracking. This hybrid approach allowed us to follow single speckles robustly in areas of high speckle density and fast flow, where previously published FSM analysis methods were unsuccessful. Thus, we can now probe cytoskeleton polymer dynamics in living cells at an entirely new level of complexity and with unprecedented detail.

Majority logic gate for magnetic quantum-dot cellular automata

We describe the operation of, and demonstrate logic functionality in, networks of physically coupled, nanometer-scale magnets designed for digital computation in magnetic quantum-dot cellular automata (MQCA) systems. MQCA offer low power dissipation and high integration density of functional elements and operate at room temperature. The basic MQCA logic gate, that is, the three-input majority logic gate, is demonstrated.

Adjusting multiple testing in multilocus analyses using the eigenvalues of a correlation matrix

Correlated multiple testing is widely performed in genetic research, particularly in multilocus analyses of complex diseases. Failure to control appropriately for the effect of multiple testing will either result in a flood of false-positive claims or in true hits being overlooked. Cheverud proposed the idea of adjusting correlated tests as if they were independent, according to an 'effective number' (M(eff)) of independent tests. However, our experience has indicated that Cheverud's estimate of the Meff is overly large and will lead to excessively conservative results. We propose a more accurate estimate of the M(eff), and design M(eff)-based procedures to control the experiment-wise significant level and the false discovery rate. In an evaluation, based on both real and simulated data, the M(eff)-based procedures were able to control the error rate accurately and consequently resulted in a power increase, especially in multilocus analyses. The results confirm that the M(eff) is a useful concept in the error-rate control of correlated tests. With its efficiency and accuracy, the M(eff) method provides an alternative to computationally intensive methods such as the permutation test.

Fully automated intensity compensation for confocal microscopic images

One well-recognized problem in three-dimensional (3D) confocal microscopic images is that the intensities in deeper slices are generally weaker than those in shallower slices. The loss of intensity with depth hampers both qualitative observation and quantitative measurement of specimens. Two major types of methods exist to compensate for this intensity loss: the first is based on the geometrical optics inside the specimen, and the second applies an empirical parametric intensity decay function (IDF) of depth. A common feature shared by both methods is that they are parameter-dependent. However, for the optics-based method there are as yet no fully automated parameter-setting approaches; and for the IDF method the traditional profile-fitting approach cannot provide proper parameters if the presumed IDF model does not match the experimental intensity-depth profile of the 3D image. In this paper, we propose a novel maximum-entropy (ME) approach to fully automated parameter-setting. In principle the ME approach is suitable for any compensation method as long as it is parameter-dependent. The basic assumption is that without intensity loss an ideal 3D image should be generally homogeneous with respect to depth and this axial homogeneity can be represented by the entropy of a normalized intensity-depth profile. Experiments on real confocal images showed that such a profile was consistent with visual evaluation of axial intensity homogeneity and that the ME approach could provide proper parameters for both compensation methods mentioned above. Moreover, for the IDF method, experiments on both real and simulated data showed that the ME approach could provide more precise parameters than with traditional profile-fitting. The Appendix provides a proof that under certain conditions the global maximization of the profile-entropy is guaranteed.

Association study of an SNP combination pattern in the dopaminergic pathway in paranoid schizophrenia: a novel strategy for complex disorders

Schizophrenia is a common mental disorder with a complex pattern of inheritance. Despite a large number of studies in the past decades, its molecular etiology remains unknown. In this study, we proposed a 'system-thinking' strategy in seeking the combined effect of susceptibility genes for a complex disorder by using paranoid schizophrenia as an example. We genotyped 85 reported single-nucleotide polymorphisms (SNPs) present in 23 genes for the dopamine (DA) metabolism pathway among 83 paranoid schizophrenics and 108 normal controls with detailed clinical and genetic information. We developed two novel multilocus approaches-the potential effective SNP combination pattern and potential effective dynamic effects analysis, by which three susceptibility genotype combinations were found to be associated with schizophrenia. These results were also validated in a family-based cohort consisting of 95 family trios of paranoid schizophrenia. The present findings suggest that the COMT and ALDH3 combination may be the most common type involved in predisposing to schizophrenia. Since the combination blocks the whole pathways for the breakdown of DA and noradrenaline, it is very likely to play a central role in developing paranoid schizophrenia.

[The effects of backpack loading on the gait and corresponding compensatory strategy]

This study was designed to determine the effect of backpack loading on the gait pattern and corresponding compensatory strategy, which is important to the balance control of biped robot and military training. Five healthy subjects were instructed to walk at their preferred speed on level pathway taking three different loads i.e. 6 kg, 12 kg and 25 kg, on their backs. The results showed that the gait pattern was apparently influenced, and the dominant effects were found to be the flexion of hip, knee joints and pitch angle of torso. The stride speed decreased apparently with loading on their backs, but the stride length showed less changes. Besides, the responses to taking loads might be influenced by the strength of body. An apparent multi-joints coordination motor mode was employed to compensate the influences of loading, however, their contributions are different; hip, knee joints and torso pitch made dominant contributions to the compensation while ankle joints made minor. The anterior pitch of upper torso could be employed to adjust the overall center of mass while loading on their backs, the larger the magnitude of loading on their backs, the larger the anterior pitch angle of torso. After the heel touched the ground, the flexion of hip and knee joints were effective for the shock absorption, which means that the stiffness of hip and knee joints can be used to absorb the shock and avoid the trauma of each joints.

Retrospective analysis of 1312 patients with haemophilia and related disorders in a single Chinese institute

With 1.3 billion people, China has the largest population in the world, and therefore has the largest population of persons with haemophilia (PWH). As there is no national registry for haemophilia, it is difficult to ascertain how many PWH have actually been diagnosed. Between January 1983 and June 2002, 1312 patients with coagulation disorders were referred to our hospital, and 1190 patients were evaluable. Among them, 1069 (89.8%) patients had haemophilia, 68 had vWD, 20 had factor XI deficiency, 10 had acquired factor VIII inhibitor and 23 had other coagulation disorders. Of the 1069 PWH, 14.7% were unclassified, 38.4% severe, 35.7% moderate and 11.1% mild. If the unclassified cases were excluded, 45.1% were severe, 41.9% moderate and 13.0% mild. Twenty-nine of the 68 vWD patients had vWF:Ag <5%, and subcategorized as type 3 vWD. Because vWF multimer analysis was not performed in our centre, the remaining vWD patients were not subdivided.

Prevalence and clinical characteristics of mitochondrial tRNAleu(UUR) nt 3243 A-->G and nt 3316 G-->A mutations in Chinese patients with type 2 diabetes

Seven hundred and sixteen randomly selected, unrelated patients with type 2 diabetes were screened for mutations using a PCR-RFLP technique to assess the prevalence of the A-G mutation at position 3243 of the mitochondrial (mt) tRNAleu(UUR) gene in type 2 diabetes in the Chinese population. Three individuals with this mutation were identified, representing approximately 0.4% of the type 2 diabetes patients screened. Further screening of the first-degree relatives of these three patients identified another four affected carriers. In comparison with type 2 diabetic patients without the mutation, these seven carriers of the mt 3243 mutation had; (1) had an earlier onset of diabetes (38.0+/-10.1 vs. 53.4+/-10.0 year, P<0.001); (2) a lower body mass index (BMI) (19.5+/-2.0 vs. 24.9+/-10.9, P<0.0001); and (3) and lower post-challenge insulin levels (area under the curve of insulin levels during the OGTT, 2946+/-1647.2 vs. 7469+/-6647.7, P<0.01). In addition, the same 716 patients with type 2 diabetes, as well as 181 controls with normal glucose tolerance, were screened for a newly described mt 3316 G-A mutation. This mutation was found in 16 patients with type 2 diabetes (2.2%) and five controls (2.7%). Therefore, the frequency of the mutation was not significantly different in the patients and controls. Moreover, the clinical characteristics such as the age of the onset of diabetes, the BMI, and insulin levels were not significantly different between the diabetic patients with the mt 3316 G-A mutation and those without. This shows that the mt 3316 G-A mutation is a polymorphism unrelated to diabetes.

[Key technologies in image analysis of comparative genomic hybridization]

Comparative genomic hybridization has become a new technique in molecular-cytogenetics, and it has found significant applications in tumor pathology. Image analysis is an important part of comparative genomic hybridization. It analyzes the fluorescent images by many steps and finally determines whether there is any abnormality in the copy number of the test tumor tissue. This paper expatiates on the key steps in the image analysis of comparative genomic hybridization, including background correction, chromosome segmentation, chromosome axis determination, karyotyping and determining ratio profile. The future trend is also discussed.

Prevalence and clinical characteristics of mitochondrial tRNA leu(UUR) mt 3243 A-->G and ND-1 gene mt 3316 G-->A mutations in Chinese patients with type 2 diabetes

OBJECTIVE

To assess the prevalence of mitochondrial tRNA leu(UUR) gene mt 3243 A-->G mutation and ND-1 gene mt 3316 G-->A mutation in Chinese type 2 diabetes.

METHODS

716 randomly selected, unrelated patients with type 2 diabetes were screened for the mutation with a PCR-RFLP technique.

RESULTS

Three individuals with mitochondrial tRNA leu(UUR) gene mt 3243 A-->G mutation were identified, representing approximately 0.4% of the type 2 patients screened. Further screening of first-degree relatives of these 3 patients identified another 4 affected carriers. In comparison with type 2 diabetic patients without the mutation, these 7 carriers of the mt3243 mutation had: 1) an earlier diagnosis age of diabetes (38.0 +/- 10.1 year vs 53.4 +/- 10.0 year, P < 0.001); 2) lower Body Mass Index (BMI) (19.5 +/- 2.0 kg/m2 vs 24.9 +/- 10.9 kg/m2, P < 0.0001); and 3) lower post-challenge insulin levels (Area under the curve of insulin levels during the Oral Glucose Tolerance Test (OGTT), 2946 +/- 1647.2 microIU.ml-1 vs 7469 +/- 6647.7 microIU.ml-1, P < 0.01). ND-1 gene mt 3316 G-->A mutation was found in 16 patients with type 2 diabetes (2.2%) and 5 out 181 controls (2.7%) with normal glucose tolerance. Therefore, the frequency of the mutation was not different in patients and controls. Moreover, clinical characteristics such as age of onset of diabetes, BMI, and insulin levels were not different between diabetic patients with the mt 3316 mutation and those without it.

CONCLUSIONS

In this large cohort of Chinese Type 2 diabetes, the prevalence of mitochondrial tRNA leu(UUR) gene mt 3243 A-->G mutation was 0.4%, and the ND-1 gene mt 3316 G-->A mutation is a polymorphism unrelated to diabetes.

[Probing and analyzing Zhang Jingyue's "concept of tonifying kidney's yin and yang"]

Zhang Jingyue, a doctor of the Ming dynasty, is good at warming and tonifying, paying attention to tonifying the kidney. Based on the requirement of theory and practice, he held that: the method of tonifying kidney may be based on kidney -- yin; the using of bringing up yin, may be measured by containing yang, while the wonderful matter of supporting yang, may be producing yang with fostering yin. These form a unique scientific thought of "concept of tonifying kidney's yin and yang".

[Gene diagnosis of factor VIII gene inversion by LD-PCR for 60 patients with severe hemophilia A]

OBJECTIVE

To identify factor VIII(F VIII) gene inversion among 60 patients with severe hemophilia A (HA) in Tianjin region.

METHODS

DNA was extracted from peripheral blood of HA patients; F VIII gene inversion was identified by long distance-polymerase chain reaction(LD-PCR) and 0.6% agarose gel electrophoresis. Those with only 11 kb band were diagnosed as the cases of F VIII gene inversion. Those with only 12 kb band were identified as wild type(non-inversion), and those with both 11 kb and 12 kb bands were recognized as inversion carriers.

RESULTS

There were 21 patients with F VIII gene inversion, accounting for 35% of the 60 patients with severe HA.

CONCLUSION

LD-PCR can be used to detect the F VIII gene inversion directly; it is an effective method for the gene diagnosis of severe hemophilia A.

Overexpression of candidate tumor suppressor gene FUS1 isolated from the 3p21.3 homozygous deletion region leads to G1 arrest and growth inhibition of lung cancer cells

Recently we identified FUS1 as a candidate tumor suppressor gene (TSG) in the 120 kb 3p21.3 critical region contained in nested lung and breast cancer homozygous deletions. Mutation of FUS1 is infrequent in lung cancers which we have confirmed in 40 other primary lung cancers. In addition, we found no evidence for FUS1 promoter region methylation. Because haploinsufficiency or low expression of Fus1 may play a role in lung tumorigenesis, we tested the effect of exogenously induced overexpression of Fus1 protein and found 60-80% inhibition of colony formation for non-small cell lung cancer lines NCI-H1299 (showing allele loss for FUS1) and NCI-H322 (containing only a mutated FUS1 allele) in vitro. By contrast, a similar level of expression of a tumor-acquired mutant form of FUS1 protein did not significantly suppress colony formation. Also, induced expression of Fus1 under the control of an Ecdysone regulated promoter decreased colony formation 75%, increased the doubling time twofold, and arrested H1299 cells in G1. In conclusion, our data are consistent with the hypothesis that FUS1 may function as a 3p21.3 TSG, warranting further studies of its function in the pathogenesis of human cancers.

Synergistic inhibition of human lung cancer cell growth by adenovirus-mediated wild-type p53 gene transfer in combination with docetaxel and radiation therapeutics in vitro and in vivo

Chemotherapy given sequentially or concurrently with external beam radiation therapy has emerged as a standard for the treatment of locally advanced lung cancer. Gene therapy by adenovirus-mediated wild-type p53 gene transfer has been shown to inhibit lung cancer growth in vitro, in animal models, and in human clinical trials. However, no information is available on the combined effects of p53 gene transfer, chemotherapy, and radiation therapy on lung cancer growth in vitro and in vivo. Therefore, we developed two-dimensional and three-dimensional isobologram modeling and statistical methods to evaluate the synergistic, additive, or antagonistic efficacy among these therapeutic agents in human non-small cell lung cancer cell lines A549, H460, H322, and H1299, at the ID50 and ID80 levels. The combination of these three therapeutic agents exhibited synergistic inhibitory effects on tumor cell growth in all four cell lines at both the ID50 and the ID80 levels in vitro. In mouse models with H1299 and A549 xenografts, combined treatment synergistically inhibited tumor growth in the absence of any apparent increase in toxicity, when compared with other treatment and control groups. Together, our findings suggest that a combination of gene therapy, chemotherapy, and radiation therapy may be an effective strategy for human cancer treatment.

Disturbed expression of Fas/FasL on CD4(+) and CD8(+)T cells in Behcet's disease, Vogt-Koyanagi-Harada syndrome, and idiopathic anterior uveitis

AIMS

To evaluate the expression of Fas/FasL antigen on peripheral blood T lymphocytes in patients with Behcet's disease, Vogt-Koyanagi-Harada (VKH) syndrome, and idiopathic anterior uveitis.

METHODS

The expression of Fas and FasL on peripheral blood T lymphocytes was determined using flow cytometry in 26 patients with Behcet's disease (BD), 17 patients with VKH syndrome, 25 patients with idiopathic anterior uveitis, and 43 healthy individuals (controls).

RESULTS

A higher proportion of CD4(+) T cells expressing Fas was noted in patients with Behcet's disease (25.70 +/- 7.32%), VKH syndrome (19.60 +/- 11.02%), and idiopathic anterior uveitis (20.81+/- 7.40%) compared with controls (14.02 +/- 6.30%). The expression of Fas on CD8(+) cells from patients with Behcet's disease (9.47 +/- 6.97%) and VKH syndrome (6.84+/- 5.5%) was also higher than that seen in controls (3.47+/- 2.75%). There was no difference in FasL expression on T cells between patients and controls except that a lower expression of FasL on CD8(+) T cells was noted in patients with idiopathic anterior uveitis.

CONCLUSION

A disturbed expression of Fas and FasL on T cells is present in patients with Behcet's disease, VKH syndrome, and idiopathic anterior uveitis, which may be involved in the perpetuation and recurrence of uveitis.

Discerning ionic currents and their kinetics from input impedance data

The excitable nature of a biological cell is manifested in the many voltage gated ion channels that perforate its membrane. The forms of the associated ionic currents, and in particular the functions that govern their kinetics, permit one to distinguish, electrophysiologically, between various cell types. We show, in the context of FitzHugh-Nagumo and Morris-Lecar models and without recourse to voltage or space clamping, that such currents and kinetics may be stably inferred from a cell's voltage response to a specified input current.

[A preliminary study on ecological response of dominant tree species in Korean pine broadleaf forest at Changbai Mountain to soil water stress and their biomass allocation]

Pot culture experiments were conducted to examine the ecological response and biomass allocation of Pinus koraienes, Fraxinus mandshurica, Juglans mandshurica, Tilia amurensis, and Quercus mongolica. The five dominant species in the Korean pine-broadleaf forest at Changbai mountain. Their seedlings were grown under three different soil moistures, e.g., 85%-100% (CK), 65%-85% (MW) and 45%-65% (LW) of field water-holding capacity. The results showed that drought significantly decreased the individual leaf area, number of fine root, root length, and individual biomass of seedlings. The root proportions of T. amurensis and F. mandshurica increased with increasing soil water content, but the leaf proportion of J. mandshurica and Q. mongolica in MW treatment was higher than that of CK and LW. There was no significant difference in stem proportions of 5 tree species among different water stress treatments. The response of the biomass of 5 tree species to water stress was significant, the total biomass of T. amurensis, F. mandshurica, J. mandshurica and P. koraienes in MW and LW decreased by 32.8%, 43.6%, 26.2% and 23.8%, respectively, while that in Q. mongolica increased by 4.8%, indicating that Q. mogolica was the most drought-tolerent species among 5 tested species.

How to optimize OCT image

Quantization, which maps real values of raw data to a series of fixed gray levels, is an inevitable step in Optical Coherence Tomography (OCT) image formation. Three new quantization methods, Minimum Distortion, Information Expansion and Maximum Entropy are applied in the specific problem. Quantization results of a capillary with milk and the femoralis of rabbit are shown in this paper. Comparisons with the present log-based methods show that a suitable quantization method significantly increases contrast, SNR and visual fineness of the final image and reduces quantization error effectively. Applicability of different quantization methods is also discussed.

[Association of 16189 variant (T-->C transition) of mitochondrial DNA with genetic predisposition to type 2 diabetes in Chinese populations]

OBJECTIVE

To assess the prevalence of 16189 variant (T-->C transition) of mitochondrial DNA in Chinese populations and to study the relation between mtDNA 16189 variant and insulin resistance and the role it plays in genetic predisposition to diabetes.

METHODS

PCR and RELP techniques were used to examine 383 unrelated type 2 diabetics and 151 non-diabetic controls selected by random sampling.

RESULTS

(1) The prevalence of 16189 variant among type 2 diabetics was significantly higher than that among the controls. (2) The prevalence of 16189 variant was significantly higher among type 2 diabetics with maternal family history than among those without maternal family history. (3) In comparison with the type 2 diabetics without 16189 variant, those with 16189 variant showed higher fasting serum insulin level, decreased insulin sensitivity index, and higher Homa insulin resistance index. (4) In the control group, no significant difference in age, gender, body mass index, waist to hip ratio, serum lipid level, fasting plasma glucose level, fasting serum insulin level, insulin sensitivity index, and Homa insulin resistance index was found between those with 16189 variant and those without 16189 variant.

CONCLUSION

16189 variant of mitochondrial DNA is one of the genetic predisposing factors for type 2 diabetes mellitus in Chinese populations. It might interfere with the energy metabolism and the production of ATP, thus causing insulin resistance in peripheral tissues.

Skin reflectance in the Han Chinese and Tibetan populations

Genetic and environmental factors are involved in the determination of skin pigmentation in humans. With the recent development of statistical and genetic tools in mapping complex traits in humans, it is becoming feasible to utilize such methods in identifying genes involved in skin pigmentation. Furthermore, the use of new portable reflectance spectroscopy instruments such as the Photovolt ColorWalk colorimeter allows researchers to measure skin reflectance of a large number of subjects with ease and accuracy. We used a new portable instrument (Photovolt ColorWalk) to study the skin reflectance of 372 Han Chinese and 274 Tibetan individuals to establish background reflectance measurements of unexposed skin of the inner upper arm in these two populations. In addition, we explored the effect of various factors such as age and gender on skin reflectance.

Successful treatment of primary and disseminated human lung cancers by systemic delivery of tumor suppressor genes using an improved liposome vector

Delivery of therapeutic genes to disseminated tumor sites has been a major challenge in the field of cancer gene therapy due to lack of an efficient vector delivery system. Among the various vectors currently available, liposomes have shown promise for the systemic delivery of genes to distant sites with minimal toxicity. In this report, we describe an improved extruded DOTAP:cholesterol (DOTAP:Chol) cationic liposome that efficiently delivers therapeutic tumor suppressor genes p53 and FHIT, which are frequently altered in lung cancer, to localized human primary lung cancers and to experimental disseminated metastases. Transgene expression was observed in 25% of tumor cells per tumor in primary tumors and 10% in disseminated tumors. When treated with DOTAP:Chol-p53 and -FHIT complex, significant suppression was observed in both primary (P < 0.02) and metastatic lung tumor growth (P < 0.007). Furthermore, repeated multiple treatments revealed a 2.5-fold increase in gene expression and increased therapeutic efficacy compared to single treatment. Finally, animal survival experiments revealed prolonged survival (median survival time: 76 days, P < 0.001 for H1299; and 96 days, P = 0.04 for A549) when treated with liposome-p53 DNA complex. Our findings may be of importance in the development of treatments for primary and disseminated human lung cancers.

[GC-MS analysis of essential oils from rhizomes of Atractylodes lancea (Thunb.) DC. and A. chinensis (DC.) Koidz]

OBJECTIVE

To analyze the constituents from the rhizomes of Atractylodes lancea and A. chinensis in essential oils.

METHOD

GC-MS method was used.

RESULT

32 and 29 compounds were identified respectively.

CONCLUSION

The main constituents in the essential oils from the rhizome of A. chinensis are beta-eudesmol or a mixture of beta-eudesmol and atractylone, whereas from that of A. lancea are hinesol, a mixture of beta-eudesmol and atractylone, and atractylone.

Water stress and accumulation of beta-N-oxalyl-L-alpha,beta-diaminopropionic acid in grass pea (Lathyrus sativus)

Grass pea seedlings were grown in an irrigated field. Roots of 15-day-old seedlings were treated with PEG, and leaves were studied. With the duration of PEG treatment, changes in the lipid peroxidation and activities of superoxide dismutase, catalase, peroxidase, and glutathione reductase as well as contents of hydrogen peroxide and beta-N-oxalyl-L-alpha,beta-diaminopropionic acid (ODAP) were assayed. The results indicate that with the duration of PEG treatment, activities of superoxide dismutase, peroxidase, and catalase decreased, whereas contents of hydrogen peroxide and ODAP, extent of lipid peroxidation, and activity of glutathione reductase increased. Both diethyldithiocarbamate and aminotriazole strongly inhibit activities of superoxide dismutase and catalase, respectively. At same time, the extent of lipid peroxidation was obviously increased. However, mannitol decreased the extent of lipid peroxidation. Diethyldithiocarbamate, aminotriazole, and mannitol do not affect the accumulation of ODAP. The observations suggest that there is no direct relationship between the accumulation of ODAP and the metabolism of free radicals. In addition, the relationship between water stress and ODAP accumulation in grass pea is discussed.