Generation of near-infrared frequency combs from a MgF₂ whispering gallery mode resonator

We report on generation of a 20 nm wide, 35 GHz repetition rate optical frequency comb in a magnesium fluoride whispering gallery mode resonator pumped with 2 mW of 1543 nm light. The high efficiency of comb generation is associated with the small anomalous group velocity dispersion of the resonator. Growth dynamics of the comb is studied and compared with earlier theoretical predictions.

Serological and virological surveillance of swine H1N1 and H3N2 influenza virus infection in two farms located in Hubei province, central China

Swine influenza viruses H1N1 and H3N2 have been reported in the swine population worldwide. From June 2008 to June 2009, we carried out serological and virological surveillance of swine influenza in the Hubei province in central China. The serological results indicated that antibodies to H1N1 swine influenza virus in the swine population were high with a 42.5% (204/480) positive rate, whereas antibodies to H3N2 swine influenza virus were low with a 7.9% (38/480) positive rate. Virological surveillance showed that only one sample from weanling pigs was positive by RT-PCR. Phylogenetic analysis of the hemagglutinin and neuraminidase genes revealed that the A/Sw/HB/S1/2009 isolate was closely related to avian-like H1N1 viruses and seemed to be derived from the European swine H1N1 viruses. In conclusion, H1N1 influenza viruses were more dominant in the pig population than H3N2 influenza viruses in central China, and infection with avian-like H1N1 viruses persistently emerged in the swine population in the area.

Basic public health services delivered in an urban community: a qualitative study

OBJECTIVES

To understand the advancements in and barriers to the implementation of measures to improve basic public health services in an urban Chinese community.

STUDY DESIGN

A qualitative study based on semi-structured interviews. Interviews were audio-taped, transcribed and analysed using thematic content analysis.

METHODS

In-depth interviews were undertaken with the directors of the management centres for community health services in 15 of the 18 districts in Beijing from December 2008 to February 2009. Content analysis of the data was completed in May 2009.

RESULTS

Fifteen types of free basic public health services had been delivered in Beijing. Some were supplied at a low level. An average of £2.38 per person per year was provided for inhabitants since 2008, but demand for funding far exceeded monies available. Teams consisting of general practitioners, community nurses and public health specialists delivered these services. The number of practitioners and their low levels of skill were insufficient to provide adequate services for community residents. Respondents gave recommendations of how to resolve the above problems.

CONCLUSIONS

In order to improve the delivery of basic public health services, it is necessary for Beijing Municipal Government to supply clear and detailed protocols, increase funding and increase the number of skilled practitioners in the community health services.

Passively mode-locked Raman laser

We report on the observation of a mode-locked laser generated with a crystalline whispering gallery mode resonator pumped with a continuous wave laser. Optical pumping of the resonator generates an optical frequency comb with phase locked components at the Raman offset of the resonator host material. Phase locking of the modes is confirmed via measurement of the radio-frequency beat note produced by the comb on a fast photodiode. Neither the conventional Kerr comb nor hyperparametric oscillation is observed when the comb is present. We present a theoretical explanation of the effect.

Carbon monoxide releasing molecule-3 inhibits concurrent tumor necrosis factor-α- and interleukin-1β-induced expression of adhesion molecules on human gingival fibroblasts

BACKGROUND AND OBJECTIVE

Carbon monoxide releasing molecule-3 (CORM-3) is a newly reported compound that has shown anti-inflammatory effects in a number of cells. In this study, we aimed to investigate the influence of CORM-3 on concurrent tumor necrosis factor-α (TNF-α)- and interleukin (IL)-1β-induced expression of adhesion molecules on human gingival fibroblasts (HGF).

MATERIAL AND METHODS

HGF were cultured from the explants of normal gingival tissues. Cells were costimulated with TNF-α and IL-1β in the presence or absence of CORM-3 for different periods of time. The expression of adhesion molecules, nuclear factor-kappaB (NF-κB) and phosphorylated p38 was studied using western blotting. RT-PCR was applied to check the expression of the adhesion molecules at the mRNA level. The activity of NF-κB was analysed using a reporter gene assay.

RESULTS

CORM-3 inhibited the up-regulation of intercellular adhesion molecule 1, vascular cell adhesion molecule 1 and endothelial leukocyte adhesion molecule in HGF after costimulation with TNF-α and IL-1β, which resulted in the decreased adhesion of peripheral blood mononuclear cells to these cells. Sustained activation of the NF-κB pathway by costimulation with TNF-α and IL-1β was suppressed by CORM-3, which was reflected by a reduced NF-κB response element-dependent luciferase activity and decreased nuclear NF-κB-p65 expression. CORM-3 inhibited MAPK p38 phosphorylation in response to stimulation with proinflammatory cytokines.

CONCLUSION

The results of this study bode well for the application of CORM-3 as an anti-inflammatory agent to inhibit NF-κB activity and to suppress the expression of adhesion molecules on HGF, which suggests a promising potential for CORM-3 in the treatment of inflammatory periodontal disease.

Whispering-gallery-mode-resonator-based ultranarrow linewidth external-cavity semiconductor laser

We demonstrate a miniature self-injection locked distributed-feedback laser using resonant optical feedback from a high-Q crystalline whispering-gallery-mode resonator. The linewidth reduction factor is greater than 10,000, with resultant instantaneous linewidth of less than 200 Hz. The minimal value of the Allan deviation for the laser-frequency stability is 3 x 10(-12) at the integration time of 20 micros. The laser possesses excellent spectral purity and good long-term stability.

Second-order optical filter based on a mirrored gradient index lens

We demonstrate a second-order bandpass filter using a single gradient index lens (GRIN) coated with mirrors. The filter becomes possible because of the residual and externally introduced small birefringence of the GRIN lens material. We show that the filter function can be trimmed by mechanical strain of the lens. Applications of the filter in microwave photonics are discussed.

Establishment and evaluation of a model of a community health service in an underdeveloped area of China

OBJECTIVES

To develop and evaluate an applicable model for a community health service (CHS) in an underdeveloped area of China that ensures efficient, convenient and affordable primary healthcare access for all residents.

STUDY DESIGN

The current study was carried out in Puyang, a typical medium-sized city in central-eastern China. Based on the healthcare requirements of the residents in Puyang, a CHS network was set up and its operation was evaluated from 1999 to 2006. The system is characterized by its focus on community health education (CHE).

METHODS

Firstly, 8231 residents, selected at random, were surveyed to investigate the healthcare requirements of the local residents. Meanwhile, the operation of the pre-existing healthcare resources was investigated in Puyang. Based on the information gained, a network-based CHS system was proposed and established, with CHE as the major focus. This study compared CHS operation prior to and after establishment of the network. Finally, an analytic hierarchy process based evaluation model was applied to evaluate the operation of the CHS network.

RESULTS

There was a high prevalence (86.98 per thousand) of chronic diseases among the residents who participated in this investigation. The majority (84.39%) of the residents who had healthcare requirements resorted to professional health care; the other residents did not have access to health services. Among those residents who sought professional treatment, 71.3% visited primary healthcare institutions. This information reflects the enormous requirement for a CHS in primary health care but the lack of accessibility among the residents; this motivated the authors to establish a system to solve the problem. The improvement in CHS operation after the network was established suggests the importance of a network for optimizing the primary healthcare system. The improvement was indicated by better understanding of the residents regarding the CHS, and enhanced capability of self-monitoring for chronic diseases such as hypertension after the network was established. Moreover, the residents' knowledge of health care was significantly increased and, accordingly, the incidence of health risk behaviour was reduced after the network was established. Furthermore, the CHE index between 1999 and 2006 showed good correlation (r=0.988, p<0.005) with the CHS index, suggesting the important role of CHE in CHS development.

CONCLUSIONS

A network-characterized CHS system was established in Puyang, and improved the primary healthcare situation. This study provides a feasible model for the development of a CHS in medium and small cities in underdeveloped parts of China.

Voltage-controlled photonic oscillator

We report the development and demonstration of an X-band voltage-controlled photonic oscillator based on a whispering gallery mode resonator made of an electro-optic crystalline material. The oscillator has good spectral purity and wide, agile, linear tunability. We have modified the existing theoretical model of the opto-electronic oscillator to describe the performance of our tunable oscillator and have found a good agreement between the theoretical predictions and the measurement results. We show that the device is promising for higher-frequency applications where high-performance tunable oscillators with wide tunability do not exist.

Collective emission and absorption in a linear resonator chain

We show that a linear chain of circular macroscopic resonators coupled in parallel demonstrates the phenomena of "superabsorption" and superradiance. Both the frequency spectrum of the transmitted light through the resonator chain and the decay rate of the resonator chain being prepared in a proper initial state are proportional to the number of resonators in the chain, N, and the intensity of the emitted radiation grows as N(2). The spectral bandwidth, the growth of the decay rate, and the intensity are restricted by the dispersion of the waveguides connecting the resonators.

Narrowband tunable photonic notch filter

We propose a technique for realization of a high-contrast, tunable, low-insertion-loss notch filter using polarization selectivity of whispering-gallery-mode resonators. We demonstrate a 10 MHz filter with 5.5 dB insertion loss and 45.5 dB of in-band rejection. The measured rejection value is limited by the finite (3 kHz) linewidth of our laser. We show that the filter can potentially have tunable bandwidth without significant rejection modification.

Tunable optical single-sideband modulator with complete sideband suppression

We report on the development of a new class of widely tunable resonant single-sideband electro-optical modulators based on interaction of different mode families of a crystalline whispering gallery mode resonator with an externally applied rf field. The tunability comes from the different response of mode families to either the temperature change or the voltage applied to the resonator.

Hindsight: a re-analysis of the severe acute respiratory syndrome outbreak in Beijing

OBJECTIVE

To review the severe acute respiratory syndrome (SARS) epidemic in Beijing using basic epidemiological principles omitted from the original analysis.

STUDY DESIGN

Analysis of Prospective surveillance data for Beijing collected during the outbreak.

METHODS

Surveillance data were reclassified according to World Health Organization criteria. Cases previously excluded without date of onset of illness were included in the epidemic curve from estimates using the average time between date of onset and date of hospitalization for cases with both dates. Cases who failed to give a contact history were now included; 7% (n=5) of cases during the import phase and 61% (n=365) during the peak phase. Previously excluded cases were included for plotting on an epidemic curve, and basic spot mapping for distribution of cases was used from attack rates recalculated for age, gender, occupation, residential location, date of onset of illness and demographics.

RESULTS

The spot map effectively illustrated clusters by residency, with the inner-city sustaining the highest attack rate (33.42 per 100,000), followed by an easterly distribution 5-30km away (21.62 per 10,000), and lowest in districts 60-160km away (9.21 per 100,000). The new epidemic curve shows the outbreak commencing 10 days earlier than initially reported, with a three-fold greater increase in cases during the escalation phase than previously estimated.

CONCLUSION

In hindsight, the investigation of the Beijing SARS would have benefited from the use of spot maping as an essential outbreak tool for early identification of specific geographical area(s) for quarantining. If a spot map of incidence density rates was used during the early phase of the outbreak, the inner city might have been identified as a major risk factor requiring rapid quarantining. Contact history became uncommon as the outbreak progressed, suggesting that hospitals were over-burdened or pathogenesis and environment risk factors changed, strengthening the usefulness of early spot mapping and the need to modify risk factors included as contact history as the epidemic progresses.

No significant differences in histology and response to interferon treatment in hepatitis B carriers of genotypes C and recombinant B

Hepatitis B virus (HBV) genotypes B and C are most prevalent in China and genotype B is found exclusively in recombination with the pre-C/C gene of genotype C. We investigated whether there is a difference in clinical relevance between the two genotypes sharing the same pre-C/C gene. Thus, we determined the genotype of HBV among consecutive HBeAg-positive patients with tailored interferon-alpha (IFN-alpha) therapy, and the demographic, baseline clinical characteristics and treatment results were compared between them. The median values of alanine transaminase (ALT) were 4.5 and 5.0 times the upper limit of normal (P = 0.419), HBV-DNA levels were 1.4 x 10(7) and 1.5 x 10(7)copies/mL (P = 0.829), mean scores of necroinflammatory histological activity 9.8 and 10.44 (P = 0.105) and fibrotic activity 2.64 and 2.86 (P = 0.227) in genotype B and C patients, respectively. The end-of-treatment response was 42.7% and 39.0% (P = 0.531) with mean tailored treatment months of 8.28 and 9.34 (P = 0.160), and the sustained response 43.4% and 37.5% (P = 0.31) at the end of a 12-month follow-up period in genotype B and C patients, respectively. These results remained similar when follow-up was extended to nearly 3 years. In conclusion, no significant differences in clinical characteristics and response to IFN-alpha between genotypes B and C were found, probably, because both types shared a common pre-C/C encoding region.

Encapsulation of ATP into liposomes by different methods: optimization of the procedure

Different methods and conditions for ATP incorporation into PEGylated liposomes were compared in order to obtain a preparation with a maximized ATP content. Such a preparation may find the application for the in vivo treatment of ischemic tissues suffering from an insufficient ATP supply. Several different methods of liposome preparation and purification were used and HPLC was employed to determine the concentration of ATP in the liposomes. Thin lipid film hydration produced vesicles with the lowest ATP encapsulation (ca. 5 mol%). A pH gradient method yielded liposomes with ca. 10 mol% of ATP. Reverse phase evaporation and freezing-thawing methods resulted in a maximum entrapment of ATP on the level of 36-38 mol%. The freezing-thawing method was chosen for further investigation because of its simplicity and absence of a need to use organic solvents. The separation of the non-entrapped ATP by gel-filtration, centrifugation or dialysis yielded virtually identical liposomal preparations. The incorporation of PEG (as PEG-distearoyl phosphatidylethanolamine, PEG-DSPE) into the liposomal membrane decreases the quantity of the entrapped ATP (from 38 mol% for liposomes with 0.5 mol% of PEG-DSPE to only 17 mol% for liposomes with 5 mol% of PEG-DSPE).

Chemical and Biological Characterization and Clinical Evaluation of Botanical Dietary Supplements: A Phase I Red Clover Extract as a Model

Botanical dietary supplements, as compared with nutritional supplements or single-component pharmaceutical drugs, are typically less-refined preparations derived from bulk plant material and, as such, require a modified approach to their development, production, and evaluation. An integrated, multidisciplinary team of scientific and clinical investigators is required in order to develop high quality phytomedicines and rigorously evaluate their safety and efficacy. Research on botanicals involves unique challenges as plant source materials frequently vary in chemical content and may contain unwanted pesticides, heavy metals, contaminant plant species, or other adulterants. Ideally, a botanical formulation should be standardized, both chemically and biologically, by a combination of analytical techniques and bioassays. This combination approach provides multiple measures by which reproducible quality and efficacy of botanical supplements may be achieved, and is particularly useful for botanical products for which the active compound(s) have not yet been identified. Safety and toxicity should be evaluated during the supplement development process in both in vitro and in vivo systems. A number of liquid chromatography-mass spectrometry methods can aid in the assessment of purity, bioavailability, toxicity, metabolism, and molecular target profiling of botanical extracts. Clinical investigators must appreciate the complexity of multi-component phytomedicines and adjust trial protocols accordingly. This review highlights practical considerations of value to basic science and clinical investigators engaged in the study of botanical supplements. Lessons and examples are drawn from the authors' experience in designing and developing a red clover (Trifolium pratense L.) standardized extract for evaluation in Phase I and Phase II clinical trials.

[Studies on the experimental transmission of Rattus-borne Hantavirus by Ornithonyssus bacoti]

AIM

To demonstrate the role of rat mite (Ornithonyssus bacoti) in the transmission of Rattus-borne hemorrhagic fever with renal syndrome (HFRS).

METHODS

In the transmission experiments, about 100 O. bacoti per pool were isolated and placed in a jar, unfed for 4 d at 23 +/- 1 degrees C. Suckling Wistar rats inoculated with Hantavirus strain Z45 or Seoul virus strain UR were placed in each jar for free attack by the mites for 12 hours. After 14 d the normal suckling Wistar rats were bitten by the mites. Fifteen days later, the lung tissues and sera of the infected rats were collected and detected for Hantaviral antigen by indirect fluorescent antibody technique (IFAT). For demonstration of the infection of O. bacti with Rattus-borne Hantavirus PCR technique was applied to detect Rattus-borne Hantaviral RNA.

RESULTS

Sukling Wistar rats inoculted Hantavirus strain Z45 or Seoul virus strain UR were bitten by O. bacoti and then these mites were fed on 4 and 5 of normal suckling rats in each jar, respectively. The antigens of Hantavirus strain Z45 were positive in all the lungs of the normal rats bitten by the mites, the sera titers of the rats were from 1:10 to 1:40. The antigens were positive in 3 of the 4 rats, the sera titers were from 1:20 to 1:40. Both of the viruses could be maintained in O. bacoti for 22 days. The blocking test showed when 1:30 Hantavirus immunosera were exposed to the lung samples and then reacted with the sera from the patients with HFRS, all the specific fluorescence reactions of the samples were blocked, whereas the control group including the normal rat lung tissues and sera were all negative (Fig. 1).

CONCLUSION

O. bacoti might play a role as the vector of HFRS and a reservoir host as well.

Calcitonin gene-related peptide immunoreactive cells and fibers in forebrain vocal and auditory nuclei of the budgerigar (Melopsittacus undulatus)

The distributions of calcitonin gene-related peptide (CGRP) immunoreactive neurons and fibers were mapped within forebrain vocal control and auditory nuclei of a vocal learning psittacine species, the budgerigar (Melopsittacus undulatus). Immunoreactivity was exhibited by telencephalic nuclei previously associated with vocal control pathways on the basis of both tract tracing studies and gene mapping: the central nucleus of the anterior archistriatum (AAc), central nucleus of the lateral neostriatum (NLc), magnocellular nucleus the lobus parolfactorius (LPOm), the oval nucleus of the ventral hyperstiratum (HVo) and the medial division of the oval nucleus of the anterior neostriatum (NAom). The main body of NAo also contained an exceptionally high density of immunoreactive fibers. In contrast to the condition in oscine songbirds, CGRP-positive neuronal somata were not present in any telencephalic vocal control nucleus. CGRP-positive somata were present, however, in diencephalic cell groups that included the shell region of the nucleus ovoidalis (Ov), the nucleus dorsolateralis posterior (DLP) and a region of the ventral thalamus that was retrogradely labeled by tracer deposits into HVo and AAc. CGRP immunoreactive fibers were observed within auditory areas of the telencephalon including Field L and the neostriatum intermedium pars dorsolateralis. The likely sources of these fibers are CGRP-positive neurons within the Ov shell and DLP.

Ca(2+) removal mechanisms in freshly isolated rabbit aortic endothelial cells

Calcium removal from the cytoplasm was investigated in freshly isolated aortic endothelial cells by monitoring changes in intracellular calcium ([Ca(2+)](i)) using ratiometric fura-2 fluorimetry. Blockade of the Na(+)/Ca(2+) exchanger (NCX) by replacement of external sodium with equi-molar N-methyl-D-glutamine (0Na PSS) decreased the removal rate by 52%. Blockade of the sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA) by cyclopiazonic acid (CPA) decreased the removal rate by 50%. Simultaneous application of CPA and 0Na PSS did not reduce the removal rate any further (53%). The lack of additivity of these two procedures, suggests that SERCA and the NCX function in series to lower [Ca(2+)](i). In addition, in the absence of extracellular Ca(2+), removal of external Na(+) markedly reduced the rate of loss of Ca(2+) from the ER further supporting the hypothesis that NCX is functionally linked to ER calcium release channels, and thus, plays an important role in ER calcium unloading. To investigate the mechanism for the coupling of NCX and SERCA, the same protocols as described above were repeated after treating the cells with cytochalasin D, which disrupts the cytoskeleton. This treatment uncoupled the NCX from SERCA, as evidenced by the resulting additive inhibitory effects of application of CPA and removal of extracellular Na(+) on the rate of Ca(2+) removal from the cytoplasm. These data suggest that in endothelial cells NCX and SERCA function in series to remove about half of the free Ca(2+) from the cytosol, while PMCA contributes to the other half of the Ca(2+) removal process.

Quantitative analysis of beta-adrenergic receptor subtypes in pig tissues

The density and distribution of beta1- and beta2-adrenergic receptors (betaAR) in porcine adipocytes, skeletal muscle, heart, lung, and liver were investigated using competitive displacement of ligand binding with subtype-selective ligands. Three experimental approaches were used to estimate the distribution of betaAR subtypes in adipocytes. Two approaches involved simultaneous linear regression analysis of multiple competitive displacement curves with the beta1AR-selective antagonist CGP 20712A and the beta2AR-selective ligand BRL 37344. For the third approach, radioligand saturation assays were perfomed using a concentration of CGP 20712A that completely blocked the beta1AR. All three approaches indicated the presence of multiple betaAR subtypes in porcine adipocytes and gave similar estimates for the proportion of these subtypes. Saturation assays in the presence of the beta1AR blocker CGP 20712A were conducted to determine the distribution of the betaAR subtypes in skeletal muscle, heart, lung, and liver. The proportions of the beta1AR and beta2AR were 81:19, 59:41, 72:28, 58:42, and 50:50 for adipose, skeletal muscle, heart, lung, and liver, respectively. These estimates based on receptor protein were consistent with published estimates of mRNA abundance in pig tissues but differ from estimates for other species. The predominance of beta1AR in adipocytes and skeletal muscle may contribute to the reduced efficacy of select betaAR agonists in pigs compared to other species because most of the ligands evaluated in growth studies are purported to be beta2AR selective. The density of the betaAR varied among tissues in the following order: heart = lung > adipocytes > skeletal muscle or = liver.

Effect of agricultural management on nematode communities in a mediterranean agroecosystem

The effects of agricultural management on the soil nematode community were investigated in a field study at depths of 0 to 10 cm and 10 to 20 cm during a peanut (Arachis hypogaea) growing season in Israel. Nineteen nematode families and 23 genera were observed. Rhabditidae, Cephalobus, Eucephalobus, Aphelenchus, Aphelenchoides, Tetylenchus, Tylenchus, Dorylaimus, and Discolaimus were the dominant family and genera. Ecological measures of soil nematode community structure, diversity, and maturity indices were assessed and compared between the managed (by fertilization, irrigation, and pesticide application) and unmanaged fields. The total number of nematodes at a 10-cm depth during peanut-sowing, mid-season, and harvest periods was higher in the treated (managed) plot than in the control (unmanaged) plot. Bacterivores and fungivores were the most abundant trophic groups in both plots and both depths. The relative abundance of each group averaged 60.8 to 67.3% and 11.5 to 19.6% of the nematode community, respectively. Plant parasites and omnivores-predators at the 0 to 10-cm depth were much less abundant than any other two groups in our experimental plots. During the growing season, except the harvest period, populations of plant parasites and omnivores-predators at the 10 to 20-cm depth were lower in the treated plot than in the control plot. Maturity index (MI), plant-parasite index (PPI), and ratio of fungivores and bacterivores to plant parasites (WI) were found to be more sensitive indicators than other ecological indices for assessing the response of nematode communities to agricultural management in an Israeli agroecosystem.

HTLV-1 cell lines differ in constitutively activated signaling pathways that can be altered by cytokine exposure

Examination of signaling pathways used by HTLV-1-infected rabbit cell lines revealed differences between one, RH/K30, that mediates asymptomatic infection and another, RH/K34, that causes lethal experimental leukemia. Both lines are IL-2 independent; RH/K30 produces IL-4 while RH/K34 produces IL-10. Examination of the Jak/STAT (Janus kinase/signal transducer and activator of transcription) activation of the lines revealed constitutive phosphorylation of Jak1 in both STAT6 phosphorylation, not previously reported for HTLV-1 cells, was observed in RH/K30; STAT1 and STAT3 were phosphorylated in RH/K34. Treatment with cytokines altered the activation of the STAT proteins: IL-2 induced STAT5 phosphorylation in both lines. Supernatant from RH/K34 or IL-10 induced STAT3 phosphorylation in RH/K30 cells. Supernatant from RH/K30 or IL-4 induced STAT6 phosphorylation in RH/K34 cells, which could be reversed with a Jak kinase inhibitor--AG-490.

[Function of vascular endothelial growth factor in ovarian hyperstimulation syndrome]

OBJECTIVE

To evaluate the function of vascular endothelial growth factor (VEGF) and other clinical indexes to forcast ovarian hyperstimulation syndrome (OHSS).

METHOD

Collecting the serum and follicular fluid (FF) of 42 cases in the in vitro fertilization and embryo transfer (IVF-ET) cycles and then analysis the relationship of the clinical and detected indexes between the OHSS (10 cases) and the non-OHSS (32 cases).

RESULTS

The concentration of VEGF in FF, E2 on the day of human chorionic gonadotropin (hCG) injection, basal luteinizing hormone (LH) and the number of ovum retried much higher in the OHSS than in the non-OHSS.

CONCLUSIONS

The concentration of VEGF in FF of OHSS cases is higher than that of controls, supporting the role of VEGF as a mediator of OHSS. Therefore VEGF in FF is a forcast index of OHSS.

Optical properties of single-walled 4 A carbon nanotubes

Optical properties of a series of finite sized hydrogenated carbon nanotubes with the smallest diameter of 4 A are studied systematically. Their absorption spectra are calculated with the localized-density-matrix method. The semiempirical MNDO parametric method 3 (PM3) Hamiltonian is employed. The finite optical gaps are predicted for the infinite long single-walled carbon nanotubes. Strong anisotropy characteristics of the dynamic polarizabilities are found for these tubes. The calculated results are in good agreement with the recent experimental findings. Further the compositions of the dipole-induced excitations are examined by projecting the corresponding density matrices onto the Hartree-Fock molecular orbital representation. Unlike the larger diameter carbon nanotubes whose absorption spectra are insensitive to the tube chiralities, the absorption spectra of 4 A single-walled carbon nanotubes depend very much on their chiralities. The chirality of the single-walled 4 A carbon nanotubes synthesized in the channels of the porous zeolites is thus determined to be (5,0) by comparing the calculated and measured absorption spectra.

[The electric pulse caused pore in the skin observed by fluorescence microscopy]

The objective of this study was to enunciate the difference in skin morphological changes between iontophroresis and electroporation for transdermal drug delivery (TDD). Fluorescence microscope was employed to observe the skin structure of human and snake in passive diffusion (control); iontophoresis was performed using direct current(0.5 mA/cm2) and electroporation was performed using intensive 380 V, pulse rate 4 ppm, pulse duration 5.5 ms, pulse number 100 and electric capacity 22 microF. Fluorescein was FITC. The results showed that for human skin in the passive, these were a few highlight fluorescent blots with scale of 15-30 microns and rough edge, but the edge of the blots became smooth and the scale did not change in the iontophoresis; when the scale of the blots was extended to 80-90 microns, the edge was smooth. For the snakes shin, the highlight blots were not sighted in the passive and iontophoresis, but they were found to be 25-30 microns in the electroporation. These data demonstrate that electric pulse can cause pore in the skin, thus creating a new route for drug permeation through skin.

Fabry - Perot interference in a nanotube electron waveguide

The behaviour of traditional electronic devices can be understood in terms of the classical diffusive motion of electrons. As the size of a device becomes comparable to the electron coherence length, however, quantum interference between electron waves becomes increasingly important, leading to dramatic changes in device properties. This classical-to-quantum transition in device behaviour suggests the possibility for nanometer-sized electronic elements that make use of quantum coherence. Molecular electronic devices are promising candidates for realizing such device elements because the electronic motion in molecules is inherently quantum mechanical and it can be modified by well defined chemistry. Here we describe an example of a coherent molecular electronic device whose behaviour is explicitly dependent on quantum interference between propagating electron waves-a Fabry-Perot electron resonator based on individual single-walled carbon nanotubes with near-perfect ohmic contacts to electrodes. In these devices, the nanotubes act as coherent electron waveguides, with the resonant cavity formed between the two nanotube-electrode interfaces. We use a theoretical model based on the multichannel Landauer-Büttiker formalism to analyse the device characteristics and find that coupling between the two propagating modes of the nanotubes caused by electron scattering at the nanotube-electrode interfaces is important.

[The effect of IFN-alpha 2b-thymus peptides combined therapy in chronic hepatitis B]

OBJECTIVE

To determine the effects of IFN-alpha 2b associated with thymus peptides in treatment of chronic hepatitis B.

METHODS

A total of 52 individuals with chronic hepatitis B received IFN-alpha 2b(5 x 10(6) IU/ml qod) for 6 months and thymus peptides(20 mg qod) for 3 months. 50 patients received SMMC or other medicine such as WuWeizi, CuiPenCao served as control. There were no differences between two groups in sex, age, duration and seriousness of the disease.

RESULTS

The primary outcome measure for efficacy was the percentage of HBV DNA/HBeAg negativity after 6 months therapy. Rate of HBV DNA negativity was 75% and that of HBeAg was 73.1%, the inhibitory activity of IFN-alpha 2b against HBV was significantly higher than that of the control. Except transient fever, leukopenia and thrombocytopenia appearing at the beginning of the therapy, no serious adverse events were observed.

CONCLUSION

Potent inhibitory activity against HBV of IFN-alpha 2b is suggested and much works need to be done to improve the long-term effect of the therapy.

Cost of genetic counseling and testing for BRCA1 and BRCA2 breast cancer susceptibility mutations

Counseling and predictive testing are now available for the recently isolated BRCA1 and BRCA2 breast cancer susceptibility genes. We examined the societal costs of providing this counseling and testing to women at risk of having a breast cancer susceptibility mutation. Genetic counselors in a research program prospectively monitored the time necessary to provide counseling and results disclosure. A time-motion study was used to determine time spent on phone calls, preparation, and documentation for counseling. Study participants were surveyed to determine travel time and need for dependent care during counseling. The test cost was calculated using the charge for full BRCA1/2 gene sequencing (Myriad Genetics, Inc.) multiplied by a Medicare-based cost-to-charge ratio. Counselors spent an average of 4.2 h providing genetic counseling for women at risk of having a susceptibility mutation. Genetic counseling without testing cost on average $213, whereas counseling, testing, and disclosure of results totaled $2057. A brief physician-based counseling instead of genetic counselor-based counseling would produce only small reductions in total costs. Providing counseling and testing to the study population averaged $8034 per mutation found. The cost of testing and counseling exceeded $2000. The counseling portion of the cost comprised only 16% of the total cost, with the remainder representing costs associated with testing; thus, alternatives to full genetic counseling that shorten counseling time are unlikely to have a large impact on the overall cost of counseling and testing. The cost of detecting a mutation within a population of women is highly dependent on the prevalence of the mutation in the population.

Projections of the oval nucleus of the hyperstriatum ventrale in the budgerigar: relationships with the auditory system

The afferent and efferent projections of a vocal control nucleus, the oval nucleus of the hyperstriatum ventrale (HVo), were mapped out in a parrot, the budgerigar (Melopsittacus undulatus) to determine the relationships of this nucleus to the auditory system. In budgerigars, HVo is connected to both the anterior forebrain pathway as well as to nuclei forming the descending projection system to the brainstem (Durand et al. [1997] J. Comp. Neurol. 377:179-206). Previous studies (Brauth et al. [1997] Proc. N. Y. Acad. Sci. 807:368-385; Durand and Brauth [1998] Neurosci Abstr 24:78.9) indicate that HVo lesions disrupt vocal performance and that HVo neurons show long latency electrophysiologic auditory responses. HVo has also been shown to receive input from neurons in the immediately adjacent HV (Durand et al. [1997] J. Comp. Neurol. 377:179-206). Thus, the focus of the present study was to elucidate relationships between HVo, its immediately adjacent surround and telencephalic auditory nuclei. The results show that, although the lateral and medial portions of HVo are interconnected with one another, inputs to these areas and their surrounds are distinctively different. The most substantial auditory system inputs are derived from the frontal lateral neostriatum (NFl) and supracentral nucleus of the lateral neostriatum (NLs); these project primarily to the lateral HVo and lateral HVo surround. The medial HVo and surround receive only sparse or modest input from auditory nuclei, including the caudomedial neostriatum (NCM), neostriatum intermedium pars lateralis (NIL), Fields L1 and L3, and the neostriatum intermedium pars ventrolateralis (NIVL). Other sources of input to the HVo surround include the hyperstriatum accessorium (HA), the supralaminar area of the frontal neostriatum (NAs), the ventral anterior archistriatum (AAv), the medial archistriatum (Am) and the medial HV. Neurons in the HV immediately medial to HVo project to a shell region around the entire nucleus. Both the ventral paleostriatum (VP) and ventral part of the central nucleus of the lateral neostriatum (NLc) project to HVo but not to the surround. Previously described projections (Durand et al., 1997) from HVo to the NAom, NLc, and the magnicellular nucleus of the lobus parolfactorius (LPOm) were confirmed.

[Analysis of eleven isolated transfusion transmitted virus genotype]

OBJECTIVE

To analyze transfusion transmitted virus (TTV) genotype in hepatitis patients and healthy people.

METHODS

DNA fragment of TTV was amplified by polymerase chain reaction with nested primers in eight patients with liver disease and three healthy persons. The nested PCR products were cloned and sequenced.

RESULTS

A TTV DNA sequence of 222 bp (primer sequence excluded) was compared among the 11 subjects. The similarity between N22 and WH1, WH2, WH3, GZ1, GZ2, GZ3, SD2, SD3 was 97.0%, 97.0%, 98.0%, 98.0%, 95.0%, 95.0%, 94.6% and 95.5%, respectively. The similarity between TXO11 and GZ4, SD1, XJ1 was 98.0%, 98.0% and 95.0%, respectively.

CONCLUSION

According to Okamoto's method, the eleven TTV clones are classified into two subtypes: genotype 1a and 1b.