[Effect of TCF21 on proliferation, migration and vascular production of breast cancer cells].

Objective: To investigate the effects of transcription factor 21 (TCF21) on the proliferation, apoptosis, invasion and migration and angiogenesis of human breast cancer cells (MDA-MB-231). Methods: TCF21 overexpressing plasmid was transfected into human breast cancer cell line MDA-MB-231 by liposome transfection, and Western blot was used to detect whether the transfection was successful. The effects of TCF21 overexpression on proliferation, apoptosis, invasion and migration and angiogenesis of MDA-MB-231 were detected by MTT, DAPI, Transwell and CAM. Results: The expression of TCF21 protein in Western blot showed that the TCF21 overexpression plasmid was successfully transfected into MDA-MB-231 cells. Overexpression of TCF21 inhibited the proliferation of tumor cells and inhibit the proliferation of 48 h cells after transfection. Overexpression of TCF21 inhibited tumor invasion and migration and angiogenesis, and promoted apoptosis of tumor cells. The results of Western blot showed that the protein expression of MMP-9, VEGFA and p-VEGFR2 decreased significantly after overexpression of TCF21. Conclusions: TCF21 can inhibit the proliferation, invasion and migration, angiogenesis and apoptosis of MDA-MB-231 cells. It is suggested that TCF21 can be used as a potential site for clinical diagnosis and treatment of breast cancer.

Single-fabrication-step Ge nanosphere/SiO2/SiGe heterostructures: a key enabler for realizing Ge MOS devices.

We report channel and strain engineering of self-organized, gate-stacking heterostructures comprising Ge-nanosphere gate/SiO2/SiGe-channels. An exquisitely-controlled dynamic balance between the concentrations of oxygen, Si, and Ge interstitials was effectively exploited to simultaneously create these heterostructures in a single oxidation step. Process-controlled tunability of the channel length (5-95 nm diameters for the Ge-nanospheres), gate oxide thickness (2.5-4.8 nm), as well as crystal orientation, chemical composition and strain engineering of the SiGe-channel was achieved. Single-crystalline (100) Si1-x Ge x shells with Ge content as high as x = 0.85 and with a compressive strain of 3%, as well as (110) Si1-x Ge x shells with Ge content of x = 0.35 and corresponding compressive strain of 1.5% were achieved. For each crystal orientation, our high Ge-content, highly-stressed SiGe shells feature a high degree of crystallinity and thus, provide a core 'building block' required for the fabrication of Ge-based MOS devices.

Designer germanium quantum dot phototransistor for near infrared optical detection and amplification.

We demonstrated a unique CMOS approach for the production of a high-performance germanium (Ge) quantum dot (QD) metal-oxide-semiconductor phototransistor. In the darkness, low off-state leakage (Ioff ∼ 0.27 pA µm(-2)), a high on-off current ratio (Ion/Ioff ∼ 10(6)), and good switching behaviors (subthreshold swing of 175 mV/dec) were measured on our Ge-QD phototransistor at 300 K, indicating good hetero-interfacial quality of the Ge-on-Si. Illumination makes a significant enhancement in the drain current of Ge QD phototransistors when biased at both the on- and off-states, which is a great benefit from Ge QD-mediated photoconductive and photovoltaic effects. The measured photocurrent-to-dark-current ratio (Iphoto/Idark) and the photoresponsivities from the Ge QD phototransistor are as high as 4.1 × 10(6) and 1.7 A W(-1), respectively, under an incident power of 0.9 mW at 850 nm illumination. A superior external quantum efficiency of 240% and a very fast temporal response time of 1.4 ns suggest that our Ge QD MOS phototransistor offers great promise as optical switches and transducers for Si-based optical interconnects.

Formation of Ge quantum dots array in layer-cake technique for advanced photovoltaics.

We report a simple and manageable growth method for placing dense three-dimensional Ge quantum dot (QD) arrays in a uniform or a graded size distribution, based on thermally oxidizing stacked poly-SiGe in a layer-cake technique. The QD size and spatial density in each stack can be modulated by conditions of the Ge content in poly-Si(1-x)Ge(x), oxidation, and the underlay buffer layer. Size-dependent internal structure, strain, and photoluminescence properties of Ge QDs are systematically investigated. Optimization of the processing conditions could be carried out for producing dense Ge QD arrays to maximize photovoltaic efficiency.

The sequence of the human genome.

A 2.91-billion base pair (bp) consensus sequence of the euchromatic portion of the human genome was generated by the whole-genome shotgun sequencing method. The 14.8-billion bp DNA sequence was generated over 9 months from 27,271,853 high-quality sequence reads (5.11-fold coverage of the genome) from both ends of plasmid clones made from the DNA of five individuals. Two assembly strategies-a whole-genome assembly and a regional chromosome assembly-were used, each combining sequence data from Celera and the publicly funded genome effort. The public data were shredded into 550-bp segments to create a 2.9-fold coverage of those genome regions that had been sequenced, without including biases inherent in the cloning and assembly procedure used by the publicly funded group. This brought the effective coverage in the assemblies to eightfold, reducing the number and size of gaps in the final assembly over what would be obtained with 5.11-fold coverage. The two assembly strategies yielded very similar results that largely agree with independent mapping data. The assemblies effectively cover the euchromatic regions of the human chromosomes. More than 90% of the genome is in scaffold assemblies of 100,000 bp or more, and 25% of the genome is in scaffolds of 10 million bp or larger. Analysis of the genome sequence revealed 26,588 protein-encoding transcripts for which there was strong corroborating evidence and an additional approximately 12,000 computationally derived genes with mouse matches or other weak supporting evidence. Although gene-dense clusters are obvious, almost half the genes are dispersed in low G+C sequence separated by large tracts of apparently noncoding sequence. Only 1.1% of the genome is spanned by exons, whereas 24% is in introns, with 75% of the genome being intergenic DNA. Duplications of segmental blocks, ranging in size up to chromosomal lengths, are abundant throughout the genome and reveal a complex evolutionary history. Comparative genomic analysis indicates vertebrate expansions of genes associated with neuronal function, with tissue-specific developmental regulation, and with the hemostasis and immune systems. DNA sequence comparisons between the consensus sequence and publicly funded genome data provided locations of 2.1 million single-nucleotide polymorphisms (SNPs). A random pair of human haploid genomes differed at a rate of 1 bp per 1250 on average, but there was marked heterogeneity in the level of polymorphism across the genome. Less than 1% of all SNPs resulted in variation in proteins, but the task of determining which SNPs have functional consequences remains an open challenge.

The genome sequence of Drosophila melanogaster.

The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

Comparative genomics of the eukaryotes.

A comparative analysis of the genomes of Drosophila melanogaster, Caenorhabditis elegans, and Saccharomyces cerevisiae-and the proteins they are predicted to encode-was undertaken in the context of cellular, developmental, and evolutionary processes. The nonredundant protein sets of flies and worms are similar in size and are only twice that of yeast, but different gene families are expanded in each genome, and the multidomain proteins and signaling pathways of the fly and worm are far more complex than those of yeast. The fly has orthologs to 177 of the 289 human disease genes examined and provides the foundation for rapid analysis of some of the basic processes involved in human disease.

The Cardioprotective Effects of Late-Phase Remote Preconditioning of Trauma Depends on Neurogenic Pathways and the Activation of PKC and NF-κB (But Not iNOS) in Mice.

BACKGROUND: A superficial abdominal surgical incision elicits cardioprotection against cardiac ischemia-reperfusion (I/R) injury in mice. This process, called remote preconditioning of trauma (RPCT), has both an early and a late phase. Previous investigations have demonstrated that early RPCT reduces cardiac infarct size by 80% to 85%. We evaluated the cardioprotective and molecular mechanisms of late-phase RPCT in a murine I/R injury model. METHODS: Wild-type mice, bradykinin (BK) 2 receptor knockout mice, 3M transgenic mice (nuclear factor κB [NF-κb] repressor inhibitor of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha [IκBα((S32A, S36A, Y42F))]), and inducible nitric oxide synthase (iNOS) knockout mice were analyzed using a previously established I/R injury model. A noninvasive abdominal surgical incision was made 24 hours prior to I/R injury and the infarct size was determined at 24 hours post-I/R injury. RESULTS: The results indicated that a strong cardioprotective effect occurred during late-phase RPCT (58.42% ± 1.89% sham vs 29.41% ± 4.00% late RPCT, mean area of the infarct divided by the mean area of the risk region; P ≤ .05; n = 10). Furthermore, pharmacological intervention revealed the involvement of neurogenic signaling in the beneficial effects of late RPCT via sensory and sympathetic thoracic nerves. Pharmacological experiments in transgenic mice-implicated BK receptors, ß-adrenergic receptors, protein kinase C, and NF-κB but not iNOS signaling in the cardioprotective effects of late RPCT. CONCLUSION: Late RPCT significantly decreased myocardial infarct size via neurogenic transmission and various other signaling pathways. This protective mechanism differentiates late and early RPCT. This study describes a new cardiac I/R injury prevention method and refines the concept of RPCT.

The chronic effects of long-term digoxin administration on Na+/K(+)-ATPase activity in rat tissues.

We have studied the effects of digoxin administration on Na+/K(+)-ATPase activity in heart, liver, muscle, renal medulla and aorta in the rat. Adult male rats were either treated with digoxin for 3 days, 7 days (5 mg/kg per day) or 3 months (3 mg/kg per day). Another group of rats were treated with the vehicle as controls. At the end of the experimental period, blood samples were taken for digoxin measurements, the animals were sacrificed, and the heart, liver, kidney, skeletal muscle and aorta were removed, homogenised and assayed for Na+/K(+)-ATPase activity. In all tissues except the aorta Na+/K(+)-ATPase activity was measured by an enzyme coupled reaction. Na+/K(+)-ATPase activity in the aorta was measured by a fluorometric potassium dependent 3-O-methyl fluorescein phosphatase activity. Plasma digoxin concentration in the digoxin group was 5.34 nmol/l (S.E.M., 0.09) in the 3-day group and 4.38 (0.68) and 4.89 (0.73) nmol/l in the 7-day and 3-month groups, respectively. After treatment for 3 days and 7 days, the Na+/K(+)-ATPase activity in all tissues was significantly lower in the digoxin group (the decrease in activity ranging from 13.4% in muscle to 46.9% in the renal medulla). After 3 months of treatment, Na+/K(+)-ATPase activity in all the tissues except the aorta was similar in the digoxin and control groups. In the aorta the activity remained low. We conclude that in rats digoxin administration causes upregulation of the Na+/K(+)-ATPase in most tissues.

AIDS awareness and risk behaviors among dually disordered adults.

An exploratory needs assessment was conducted among 50 clients of an abstinence-oriented outpatient clinic for adults experiencing coexisting drug abuse and chronic mental disorders. Findings revealed that, despite education and prevention efforts, sample members possessed considerable misinformation about AIDS and continued to engage in high risk heterosexual practices. Their knowledge level was not associated significantly with their admission diagnoses. Knowledge level also did not correlate significantly with safer sexual practices. These findings have implications for the development of AIDS education and prevention programs for dually disordered clients. To be effective, AIDS prevention and education efforts must be targeted at the clients' specific needs. Clear, explicit information about AIDS must be provided. In addition, behavioral-attitudinal change strategies that focus on the high-risk situations encountered by the clients and teach them alternative safer sex practices are required.

Condom knowledge, history of use, and attitudes among chemically addicted populations.

The need for behavioral change of risky sexual practices has been of the highest priority since the onset of the AIDS epidemic. The major focus of education for safe sex has been emphasis on condom use. We surveyed 124 individuals applying to treatment for various chemical dependencies and 60 individuals applying for non-chemical-dependency medical treatment on various aspects of condom knowledge, history of use, and attitudes. Respondents reported that AIDS has motivated them to increase their use of condoms, however, only 13.9% always use them. Education is needed in the areas of increasing protection. Along with the use of a condom, the need for a reservoir tip and the risks associated with multiple sex partners should be stressed.

PIP: This report contains the findings of a survey designed to investigate the knowledge of condoms, history of use, and attitudes among chemically attitudes among chemically addicted populations. The study took place in the Division of Alcohol and Drug Dependence of the SUNY Health Science Center at Brooklyn, Department of Psychiatry, Kings Country Addictive Disease Hospitals. Researchers interviewed 124 individuals seeking treatment for chemical dependency, as well as 60 individuals applying for non-chemical dependency treatment to serve as controls. 25% of those interviewed reported intravenous injection as their primary route of drug administration, 25% reported smoking crack of sniffing cocaine, 17.4% cited alcohol abuse. The remaining 32.6% made up the control group. In a few instances, drug users scored better than the controls on condom knowledge, but overall, the survey found no significant differences in the level of knowledge about AIDS and condoms use among the drug, alcohol, and control groups. As expected, the survey found that those individuals who have a history of condom use scored higher on the knowledge quiz than those with less experience. Very few individuals in any of the groups mentioned monogamy as a strategy for risk reduction, or mentioned multiple sex partners as high-risk activity. While sensitivity and embarrassment did not play a significant role in condom use frequency, 26.1% of those interviewed agreed with the statement "If my partner doesn't mention using a condom neither will I." 32% of males and 57.1% of females reported having has a sex partner refuse to use a condom. These findings, the report explains, suggest the need to address sexually risky behavior within the chemically addicted populations.

Gallstone images on plain film and endoscopic retrograde cholangiopancreatography.

Different compositions of gallstone merit different treatments if a non-surgical method is chosen for these patients. In this study, gallstones collected from 125 patients were classified into cholesterol (pure, combination, mixed N = 28), brown (N = 64) and black (N = 41) stones by the Gallstone Classification of the Japanese Study Group (1986). Plain film and endoscopic retrograde cholangiopancreatography (ERCP) were reviewed in an attempt to predict the composition of the stones. We found that shape and location were highly correlated with stone composition. Most of the sandy stones were black stones (15/19, 79%); and 48% (10/21) of the irregular stones were brown stones; 70% (14) of facet stones were brown stones, 30% cholesterol stones. Stones in the gallbladder tended to be of the cholesterol type (47%, 13/28), 64% (51/81) of the bile duct stones were brown stones and 69% (11/16) of the gallbladder and bile duct stones were brown stones. We therefore conclude that imaging studies using plain film and ERCP is a fairly accurate means of predicting the composition of gallstone.

Minimally invasive parathyroidectomy by unilateral neck dissection--experience in a regional hospital in Hong Kong.

OBJECTIVE: To compare the efficacy and safety of minimally invasive open parathyroidectomy with localised unilateral neck dissection to the conventional method of bilateral neck exploration and parathyroidectomy as a surgical treatment for primary hyperparathyroidism. PATIENTS AND METHODS: Eleven patients diagnosed with primary hyperparathyroidism at Queen Elizabeth Hospital from 1 January 2002 to 31 December 2002 were treated surgically with minimally invasive open parathyroidectomy. Their results were compared to a retrospective series of 15 patients treated by conventional bilateral neck exploration and parathyroidectomy between 1 January 2001 and 31 December 2001. Demographic data; cure, recurrence, and complication rates; operating time; and hospital stay were analysed. RESULTS: The cure rate was 100% in both groups. There was no recurrence in either group. Minor complication rates were 9% and 20% in the minimally invasive open parathyroidectomy and the control groups, respectively. Mean operating time was 63 minutes in the minimally invasive open parathyroidectomy group, and 92 minutes in the control group. The mean postoperative hospital stay for the minimally invasive open parathyroidectomy group was 1.36 days. Three of these procedures were performed as day surgery. The mean hospital stay for the control group was 2.93 days. The operating time and hospital stay were significantly shorter in the minimally invasive open parathyroidectomy group. CONCLUSION: Minimally invasive open parathyroidectomy is a viable alternative treatment method for primary hyperparathyroidism. It has comparable cure and recurrence rates to the conventional approach. It is safe, with a lower complication rate, and has the benefits of being a shorter procedure and allowing a shorter hospital stay. It can be performed as day surgery, further reducing hospital costs.

[Clinical observation of music therapy combined with anti-tumor drugs in treating 116 cases of tumor patients].

OBJECTIVE: To observe the clinical effect of music therapy in treating tumor patients. METHODS: Music therapy combined with anti-tumor drugs, including chemotherapy and Chinese drugs, was given to 162 tumor patients according to syndrome differentiation to observe the change of self-rating depression scale (SDS), self-rating anxiety scale (SAS), minnesota multiphasic personality inventory (MMPI), Hamilton rating scale for depression (HAMD) and T lymphocyte subsets (immuno-histochemical assay), NK cell anti-tumor activity (NAG method), etc. while 46 caces didn't receive music therapy were taken as the control group. RESULTS: The scale marks of SDS and SAS of the treated group after treatment were obviously lower than that of the control group significantly (P < 0.05, P < 0.01). After treatment, the average values of MMPI on falseness (F), hypochondriasis (HS), depression (D) and psychosthenia (Pt) in the treated group were all improved (P < 0.01 or P < 0.05); but in the control group, significant difference only showed in MMPI on HS (P < 0.05). HAMD in the treated group revealed some improvement in insomnia, early awakening, daily work and interest, systemic symptoms and hypochondriasis (P < 0.05), and significant improvement in depression, difficulty in falling asleep, psychiatric anxiety and somatic anxiety (P < 0.01); while in the control group, only work interest and HS had some improvement (P < 0.05). CD8 percent was reduced in both groups after treatment (P < 0.01), but in the treated group CD3, CD4 and CD4/CD8 ratio were not significantly changed after treatment (P > 0.05); while in the control group they lowered obviously (P < 0.05). As for NK cell anti-tumor activity in the treated group before and after treatment, it was not significantly lowered (P > 0.05); while in the control group the lowering after treatment was significant (P < 0.05). CONCLUSION: Music therapy could regulate the emotion of tumor patient, optimize the emotional effect, improve the somatic symptoms, enhance the immune function, motivate the active principle and raise the self-regulating power in the body.

Size tunable Ge quantum dots for near-ultraviolet to near-infrared photosensing with high figures of merit.

We report a unique approach for the inclusion of size-tunable (7-50 nm), spherical Ge quantum dots (QDs) into gate stacks of metal-oxide-semiconductor (MOS) diodes, through selective oxidation of SiGe layers over the buffer layer of Si3N4 deposited over the Si substrate. In this complementary MOS (CMOS)-compatible approach, we successfully realized high performance nm scale Ge-QD MOS photodetectors with high figures of merit of low dark current density (1.5 × 10(-3) mA cm(-2)), superior photo-current-to-dark current ratio (13 500), high photoresponsivity (2.2 A W(-1)), and fast response time (5 ns), which are ready for direct integration with Si CMOS electronic circuits. Most importantly, the detection wavelength of the Ge QDs is tunable from near infrared to near ultraviolet by reducing the QD size from 50 to 7 nm as well as the optimal photoresponsivity is tailored by the Ge QD size and the effective thickness of gate dielectrics.

Enhanced 400-600 nm photoresponsivity of metal-oxide-semiconductor diodes with multi-stack germanium quantum dots.

Metal-oxide-semiconductor (MOS) diodes with zero-, one- or three-layer Ge quantum dots (QDs) embedded in the gate oxide are fabricated for visible to near-ultraviolet photodetection. Ge dots are formed by thermally oxidizing one or three stacks of amorphous Si (a-Si)/polycrystalline-Si(0.87)Ge(0.13)/a-Si multi-layers that are sandwiched by SiO(2) barriers. The current-voltage characteristics of Ge QD MOS diodes exhibit strong rectification in darkness and feature significant current enhancement in the inversion mode when illuminated. Increasing the number of Ge QD layers from zero through one to three in the gate oxide improves the responsivity from 4.64 through 482 to 812 mA W(-1) and enhances the corresponding quantum efficiency from 1.42 through 148 to 245%, respectively. The spectral response reveals a considerable blueshift in peak energies as the Ge dot size decreases from 9.1 to 5.1 nm, suggesting that the light absorption originates from the quantum confinement effect of Ge QDs. The temperature and bias dependences of the dark current indicate that the carrier transport mechanism involves percolation hopping.

Contrasting work environments of medical school faculty.

An attitude survey has revealed vividly contrasting institutional atmosphere and working conditions at U.S. medical schools. Environments at about one-fourth of the schools were judged to be highly positive with regard to subjective atmosphere, career development, and faculty-administration relations. Environments at another one-fourth of all schools were judged to be highly negative in all of these areas. Recognizing the existence of these differences is necessary before administrative remedies for many of the problems at the latter group of schools can be implemented.