[Impact of different types of heart failure on long-term renal prognosis in patients with renal insufficiency and heart failure]

Objective: To investigate the effects of different types of heart failure on long-term renal prognosis in patients with renal insufficiency and heart failure. Methods: The patients with renal insufficiency [baseline estimated glomerular filtration rate < 60 ml·min^-1·(1.73 m²)^-1] and heart failure followed-up for more than 2 years and hospitalized in Beijing Anzhen Hospital, Capital Medical University from January 1, 2018 to June 30, 2019 were enrolled in this retrospective cohort study. The patients were divided into three groups based on the baseline left ventricular ejection fraction (LVEF): heart failure with reduced ejection fraction (HFrEF, LVEF < 40%) group, heart failure with mildly reduced ejection fraction (HFmrEF, 40% ≤ LVEF < 50%) group, and heart failure with preserved ejection fraction (HFpEF, LVEF ≥ 50%) group. Clinical data were collected and endpoint events (adverse renal outcome: the composite outcome of all-cause death or worsening renal function) were recorded through the electronic medical record system. Kaplan-Meier survival curve was used to analyze the incidence of endpoint events of different heart failure subgroups. Cox regression model was performed to analyze the risk factors of endpoint events. Results: A total of 228 patients with renal insufficiency complicated with heart failure were included, with age of (68.14±14.21) years old and 138 males (60.5%). There were 85 patients (37.3%) in the HFrEF group, 40 patients (17.5%) in the HFmrEF group, and 103 patients (45.2%) in the HFpEF group. There were statistically significant differences in age, proportion of age > 65 years old, sex distribution, systolic blood pressure, pulmonary artery pressure, serum sodium, serum calcium, hemoglobin, serum cholesterol, low-density lipoprotein cholesterol, serum uric acid, troponin I, hypersensitive C-reactive protein, LVEF, ventricular septal thickness, left ventricular end-diastolic diameter, B-type natriuretic peptide, estimated glomerular filtration rate, and proportions of using beta blockers, using spirolactone, myocardial infarction, hypertension, cardiomyopathy and atrial fibrillation (all P < 0.05). During the median follow-up of 36.0 (28.0, 46.0) months, 73 patients (32.0%) had adverse renal outcomes. The total incidences of adverse renal outcomes were 32.9% (28/85) in the HFrEF group, 35.0% (14/40) in the HFmrEF group, and 30.1% (31/103) in the HFpEF group. Kaplan-Meier survival curve showed that there was no significant difference in the incidence of endpoint events among the three groups (log-rank test χ²=0.17, P=0.680). Multivariate Cox regression analysis showed that HFpEF (HFrEF as reference, HR=2.430, 95% CI 1.055-5.596, P=0.037) was an independent influencing factor of endpoint events. Conclusions: The long-term renal prognosis of patients with renal insufficiency and heart failure is poor. Compared with HFrEF, HFpEF is an independent risk factor of poor long-term renal prognosis in renal insufficiency patients with heart failure.

Mechanical properties analysis of medical endodontic instruments based on parameterization

To study the relationship between structural parameters and mechanical properties of endodontic instruments, the T02004B25 nickel-titanium endodontic instrument was selected for bending and torsion tests and finite element simulation analysis, which demonstrated the feasibility of simulation analysis method. Then based on the idea of parametric design, the models of the endodontic instruments with different structural parameters (cross-section, pitch, taper) were established, and the bending-torsion performance simulation analysis was completed. The results showed that the mechanical properties of endodontic instruments with different structural parameters are different. It is necessary to find the optimal parameters for different structure parameters of endodontic instruments to maximize their service life.

A Review of Mechano-Biochemical Models for Testing Composite Restorations

Due to the severe mechano-biochemical conditions in the oral cavity, many dental restorations will degrade and eventually fail. For teeth restored with resin composite, the major modes of failure are secondary caries and fracture of the tooth or restoration. While clinical studies can answer some of the more practical questions, such as the rate of failure, fundamental understanding on the failure mechanism can be obtained from laboratory studies using simplified models more effectively. Reviewed in this article are the 4 main types of models used to study the degradation of resin-composite restorations, namely, animal, human in vivo or in situ, in vitro biofilm, and in vitro chemical models. The characteristics, advantages, and disadvantages of these models are discussed and compared. The tooth-restoration interface is widely considered the weakest link in a resin composite restoration. To account for the different types of degradation that can occur (i.e., demineralization, resin hydrolysis, and collagen degradation), enzymes such as esterase and collagenase found in the oral environment are used, in addition to acids, to form biochemical models to test resin-composite restorations in conjunction with mechanical loading. Furthermore, laboratory tests are usually performed in an accelerated manner to save time. It is argued that, for an accelerated multicomponent model to be representative and predictive in terms of both the mode and the speed of degradation, the individual components must be synchronized in their rates of action and be calibrated with clinical data. The process of calibrating the in vitro models against clinical data is briefly described. To achieve representative and predictive in vitro models, more comparative studies of in vivo and in vitro models are required to calibrate the laboratory studies.

Comparison of the postoperative and follow-up accuracy of articulator model surgery and virtual surgical planning in skeletal class III patients

The aim of this study was to evaluate the postoperative and follow-up accuracy of using an intermediate occlusal splint between articulator model surgery (AMS) and virtual surgical planning (VSP) in double-jaw operations. Thirty skeletal class III patients were randomly allocated to have AMS or VSP. In the AMS group surgical planning was done through conventional articulator model surgery, and an intermediate occlusal splint made of acrylic resin was used. In the VSP group the surgical simulation was done virtually, and the same intermediate splint was used in the software and then fabricated using rapid prototyping technology. Preoperatively, one week postoperatively, and 1∼2-years later we obtained follow-up cone-beam computed tomographic (CT) images of each patient. Absolute linear differences between planned and actual outcomes, as well as planned and follow-up outcomes, were evaluated. There was no significant difference in either postoperative accuracy or follow-up accuracy between the methods, and there was no significant difference in the rate of skeletal relapse. Planning transfer by intermediate splint might therefore be the dominant factor in the final inaccuracies. The potentially greater accuracy of VSP may be realised with the help of new positioning devices instead of an intermediate splint.

Evaluation of SMAP downscaled brightness temperature using SMAPEx-4/5 airborne observations

The Soil Moisture Active and Passive (SMAP) mission, launched by the National Aeronautics and Space Administration (NASA) on 31st January 2015, was designed to provide global soil moisture every 2 to 3 days at 9 km resolution by downscaling SMAP passive microwave observations obtained at 36 km resolution using active microwave observations at 3 km resolution, and then retrieving soil moisture from the resulting 9 km brightness temperature product. This study evaluated the SMAP Active/Passive (AP) downscaling algorithm together with other resolution enhancement techniques. Airborne passive microwave observations acquired at 1 km resolution over the Murrumbidgee River catchment in south-eastern Australia during the fourth and fifth Soil Moisture Active Passive Experiments (SMAPEx-4/5) were used as reference data. The SMAPEx-4/5 data were collected in May and September 2015, respectively, and aggregated to 9 km for direct comparison with a number of available resolution-enhanced brightness temperature estimates. The results show that the SMAP AP downscaled brightness temperature had a correlation coefficient (R) of 0.84 and Root-Mean-Squared Error (RMSE) of ~10 K, while SMAP Enhanced, Nearest Neighbour, Weighted Average, and the Smoothing Filter-based Modulation (SFIM) brightness temperature estimates had somewhat better performance (RMSEs of ~7 K and an R exceeding 0.9). Although the SFIM had the lowest unbiased RMSE of ~6 K, the effect of cloud cover on Ka-band observations limits data availability.

Abstract P5-21-19: Suppression of breast carcinogenesis and metastasis by targeting glucose metabolism with HJC0152

Lack of targeted strategies for preventing and treating estrogen receptor (ER)-negative breast cancer (ENBC) is an unmet clinical challenge. ENBCs including triple-negative BCs (TNBC) constitute 30-40% of BC cases and are prone to develop remote metastasis and local recurrence, resulting in the majority of deaths in BC patients. Dysregulated glucose and energy metabolism is critically involved in the development and progression of various cancers via promoting aberrant cell growth, malignant transformation and metastasis. Nevertheless, the potential role of glucose/energy metabolism in ENBC carcinogenesis has sparsely been explored, thus representing a key knowledge gap and a potential avenue for effective targeted therapies. Despite a substantial amount of effort has been made towards anticancer metabolic and biogenetic medications, none has progressed into clinical use, due to their limited potency, specificity or drug properties such as toxicity and poor bioavailability. We recently developed HJC0152, a novel small molecule anticancer agent, using structure- and fragment-based drug design strategies and molecular modeling techniques in our initial attempt to develop non-peptide STAT3 inhibitors for anticancer use. HJC0152 significantly inhibits proliferation of BC cells, induces apoptosis, reduces ER-negative mammary tumor development, suppresses ENBC xenograft tumor growth, and blocks lung metastasis in vivo. Intriguingly, HJC0152 differentially modulates expression of glycolytic enzymes including HK1, PFK-L, PFKFB2, ENO2, PDH, PDK1, PGAM1 and ALDOA in a time-dependent manner. HJC0152 also regulates the transcription of genes involved in glucose and mitochondrial energy metabolism, including the subunits of mitochondrial respiratory chain complexes. Functional assessments further demonstrate that HJC0152 significantly modulates respiratory chain complex function. Via in silico and Unique Polymer Technology (UPT) strategy, we identified a number of putative HJC0152-interacting targets for validation studies. Our findings suggest that HJC0152 is capable of reprogramming/restoring the dysregulated glucose metabolism by inducing specific glycolytic enzyme expression and mitochondrial respiratory chain function, likely via targeting upstream key signal molecule(s) that regulates glucose and energy metabolism, thereby suppressing breast cancer development and progression to metastasis. This work was supported by Grants P50 CA097007, and P30DA028821 (JZ) from the NIH, CPRIT (JZ), John Sealy Memorial Endowment Fund (JZ), DFI Grants from MD Anderson Cancer Center (QS), Holden Family Research Grant in BC Prevention (QS), and NCI PREVENT Program HHSN26100002 (QS).

Citation Format: Dong J, Kim H, Xu J, Li D, Zhang Z, Zheng Z, Ye N, Chen H, Zhou J, Shen Q. Suppression of breast carcinogenesis and metastasis by targeting glucose metabolism with HJC0152 [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-21-19.

Correction of facial asymmetry associated with vertical maxillary excess and mandibular prognathism by combined orthognathic surgery and guiding templates and splints fabricated by rapid prototyping technique

The facial asymmetry associated with vertical maxillary excess and mandibular prognathism is one of the more complicated types in the field of oral and maxillofacial surgery. The purpose of this study was to investigate the efficacy of combined orthognathic surgeries, together with guiding templates and splints fabricated by rapid prototyping technique, for the correction of facial asymmetry. Fourteen patients with facial asymmetry associated with vertical maxillary excess and mandibular prognathism were included. A maxillary Le Fort I osteotomy, a sagittal split ramus osteotomy on the shorter side of the face, and an intraoral vertical ramus osteotomy on the longer side of the face were performed with the aid of guiding templates and splints fabricated by rapid prototyping technique. Parameters reflecting maxillary canting, ramal inclination, mandibular deviation, and chin inclination were measured before surgery, 7 days after surgery, and 1 year after surgery, and compared. Significant differences in these parameters were found between the two sides preoperatively, whereas no differences were observed postoperatively. Facial asymmetry was corrected in all patients with satisfactory outcomes. In conclusion, combined orthognathic surgery and guiding templates and splints can offer improvements in accuracy, complexity, and duration over traditional procedures for the correction of facial asymmetry associated with vertical maxillary excess and mandibular prognathism.

Dense WDM transmission at 2 μm enabled by an arrayed waveguide grating

We show, for the first time, dense WDM (8×20  Gbit/s) transmission at 2 μm enabled by advanced modulation formats (4-ASK Fast-OFDM) and the development of key components, including a new arrayed waveguide grating (AWGr) at 2 μm. The AWGr shows -12.8±1.78  dB of excess loss with an 18-dB extinction ratio and a thermal tunability of 0.108 nm/°C.

10 Gb/s InP-based Mach-Zehnder modulator for operation at 2 μm wavelengths

We report on the first InP-based Mach-Zehnder modulator (MZM) employing quantum-confined Stark effect (QCSE) for operation around 2000 nm. The polarization sensitive device is based on 15 compressively strained quantum wells and achieves an electro-optic (EO) bandwidth of at least 9 GHz, with a DC extinction ratio of ~9 dB, and a V(π)L ~9.6 V.mm. We demonstrate back-to-back communication with a 10 Gb/s pseudo-random bit sequence (PRBS) of length 2(7)-1 at a wavelength around 2000 nm.

100 Gbit/s WDM transmission at 2 µm: transmission studies in both low-loss hollow core photonic bandgap fiber and solid core fiber

We show for the first time 100 Gbit/s total capacity at 2 µm waveband, using 4 × 9.3 Gbit/s 4-ASK Fast-OFDM direct modulation and 4 × 15.7 Gbit/s NRZ-OOK external modulation, spanning a 36.3 nm wide wavelength range. WDM transmission was successfully demonstrated over 1.15 km of low-loss hollow core photonic bandgap fiber (HC-PBGF) and over 1 km of solid core fiber (SCF). We conclude that the OSNR penalty associated with the SCF is minimal, while a ~1-2 dB penalty was observed after the HC-PBGF probably due to mode coupling to higher-order modes.

Metabolomics analysis of cervical cancer, cervical intraepithelial neoplasia and chronic cervicitis by 1H NMR spectroscopy

Metabolomics profiles of serum samples from women with chronic cervicitis, cervical intraepithelial neoplasia (CIN), and cervical cancer were characterized by proton nuclear magnetic resonance (1H NMR). These spectral profiles were subjected to partial least-squares discriminant analysis (PLS-DA), and good discriminations between cancerand non-cancer groups (chronic cervicitis and CIN) were achieved by multivariate modeling of serum profiles. The main metabolites contributing to these discriminations, as highlighted by multivariate analysis and confirmed by spectral integration, were formate, tyrosine, β-glucose, inositol, glycine, carnitine, glutamine, acetate, alanine, valine, isoleucine, and very-low-density lipoprotein (VLDL). Metabolomics analysis for chronic cervicitis, CIN, and cervical cancer is significant, which give a systemic metabolic response of these female diseases. The systemic metabolic response may be used to identify the potential biomarkers for the diseases.

Photoprotection in the green tidal alga Ulva prolifera: role of LHCSR and PsbS proteins in response to high light stress

Ulva prolifera, an intertidal macroalga, has to adapt to wide variations in light intensity, making this species particularly rewarding for studying the evolution of photoprotective mechanisms. Intense light induced increased non-photochemical quenching (NPQ) and stimulated de-epoxidation of xanthophyll cycle components, while DTT-treated samples had lower NPQ capacity, indicating that the xanthophyll cycle must participate in photoprotection. In this work, we found that the PsbS-related NPQ was maintained in U. prolifera. According to analysed gene expression, both LhcSR and psbS were up-regulated in high light, suggesting that these two genes are light-induced. LHCSR and PsbS proteins were present at different light intensities and accumulated under high light conditions, and PsbS concentrations were higher than LHCSR, showing that the NPQ mechanism of U. prolifera is more dependent on PsbS protein concentration. Moreover, the level of both LHCSR and PsbS proteins was high even in the darkness, and neither the transcript level nor protein content of LhcSR and psbS genes varied significantly following short-term exposure to intense light. These findings suggest that this alga can modulate NPQ levels through regulation of the xanthophyll cycle and concentrations of PsbS and/or LHCSR.

Suppression of hepatoma tumor growth by systemic administration of the phytotoxin gelonin driven by the survivin promoter

Hepatocellular carcinoma (HCC) is one of the most common types of cancer worldwide. However, there is currently no effective therapy strategy in the clinical practice. Recombinant phytotoxin gelonin fused to other factors have been used to treat different cancers. But there have been no reports of gelonin gene therapy. In this study, we have constructed a recombinant plasmid which contained a tumor-specific survivin promoter to drive phytotoxin gelonin (pSur-Gel). And the cytotoxicity effects of pSur-Gel in HCC were also validated both in vitro and in vivo. The expression level of survivin was detected in different liver cancer cell lines and normal liver cell lines by western blot analysis, and a survivin promoter-driven green fluorescent protein (GFP) expression vectors (pSur-GFP) was also tested in liver cancer cell line HepG2 and normal liver cell line LO2. Moreover, phytotoxin gelonin expression experiment and cytotoxicity experiment of pSur-Gel was performed in HepG2 cells and LO2 cells in vitro. Furthermore, anti-tumor effect of pSur-Gel against HepG2 xenografts and toxicity of this gene were evaluated in the mice model. Finally, LDH release assay, apoptosis assay and immunoblot analyse LC3 conversion (LC3-I to LC3-II) were tested. We found that the expression of survivin protein was higher in liver cancer cell lines compared with the normal liver cells. Further study showed that the pSur-GFP and pSur-Gel was expressed specially in liver cancer cell other than in normal liver cells. pSur-Gel plasmid could effectively inhibit the proliferation of liver cancer cells (*P<0.05), and significantly repress the growth of HepG2 xenografts via intravenous in vivo (*P<0.05). Otherwise, compared to cytomegalovirus promoter-driven gelonin expression vectors (pCMV-Gel), no significantly systemic toxicity or organ injuries had been observed in pSur-Gel treated mice. Further studies revealed that the phytotoxin gelonin induced cell death might be mediated by apoptosis and the damage of cell membrane. Taken together, treating hepatocellular carcinoma with the pSur-Gel may be a novel and interesting cancer gene therapy protocol and is worthy of further development for future clinical trials.

KEYWORDS

liver cancer, gelonin, survivin promoter, gene therapy.

The male sterility and histoincompatibility (mshi) mutation in mice is a natural variant of microtubule-associated protein 7 (Mtap7)

Males homozygous for the mouse male sterility and histoincompatibility (mshi) mutation exhibit small testes and produce no sperm. In addition, mshi generates an "antigen-loss" histoincompatibility barrier, such that homozygous mutants reject skin grafts from wild type co-isogenic BALB/cByJ donors. To facilitate the molecular characterization of the pleiotropic mshi mutation, we genetically mapped mshi into a 0.68 megabasepair region which contains fewer than 10 candidate genes. Complementation testing showed that one of these, Mtap7, is disrupted in mshi mice. Sequence analysis has revealed a 13 kilobasepair deletion in BALB/cByJ-mshi/J mice that begins in Intron 10-11 of Mtap7, and ends less than 2000 base pairs downstream of the wild type gene. Analysis of the mutant cDNA predicts that Mtap7(mshi) encodes a 457 amino acid protein, the first 423 of which are identical to wild type, and the last 34 of which are due to aberrant mRNA splicing with two cryptic exons in the Mtap7 to P04Rik intergenic region. This molecular assignment for the mshi mutation further supports an essential role for microtubule stabilization in spermatogenesis and indicates a new role in allograft transplantation.

Two-way ANOVA to identify impacts of multiple interactive behavioral factors on the neuronal population dependency during the reaching motion

Brain neural activities interact with behaviors. The contribution of this paper is that we investigate the significance of the impacts of multiple behavioral factors: target direction (left or right) and obstacle (presence or absence), and their interaction on the dependency among a neuronal ensemble in the dorsal premotor (PMd) area of a monkey during a reaching motion. We first use bootstrapping to extract multiple resamples from successful trials. Then we use redundancy to measure dependency in each resample. We use ANOVA to investigate the significance of the impacts of these two behavioral factors and their interaction on the redundancy. The ANOVA shows that these two behavioral factors and their interaction have significant impacts on the single feature of neural activity. The same significance of impacts is identified in another neuronal ensemble assessed in another experimental session. Its biological explanation is given.

A cluster analysis of neuronal activity in the dorsal premotor cortical area for neuroprosthetic control

With the use of the neuronal data acquisition technology, millisecond-level multi-electrode data from several regions of the premotor area were obtained from two rhesus monkeys trained to perform arm-reach tasks with visual cues in virtual reality. In each trial, animals were required to select and perform one of the four possible arm reaching movements to the target on the top-left or top-right of the virtual reality space. They were also required to decide whether they would move their arms straight to the target or curve them in order to avoid the obstacle that was presented. After the acquired neuronal signals were processed, unsupervised Hierarchical clustering and K-means clustering were performed to uncover the similarity and difference in the average firing rate of spike train data between neurons and phases for each experiment condition. The clustering results indicate the similarity of neuronal data in the movement planning and actual movement phases, and the difference of such data from the data in information processing phases. Furthermore, the clustering results show that when the target location is on the right, the move planning started earlier. The analysis of variance (ANOVA) on the neuronal data confirms the results from the hierarchical clustering.

Typical and atypical antipsychotic drugs target dopamine and cyclic AMP-regulated phosphoprotein, 32 kDa and neurotensin-containing neurons, but not GABAergic interneurons in the shell of nucleus accumbens of ventral striatum

Specific neurons in the brain are the primary targets of the action of antipsychotic drugs. Identification and characterization of the nature of these neurons are important for understanding how antipsychotic drugs produce their effects. In previous studies GABAergic/dynorphinergic neurons were identified as a principal cell target of antipsychotic drugs in the shell of nucleus accumbens. In the present study, we further characterized which subpopulations of GABAergic neurons in this area respond after acute administration of antipsychotic drugs. Rats were treated with the typical antipsychotic haloperidol, or the prototype atypical antipsychotic clozapine and killed two hours after treatment. In appropriate sections of brain, double immunofluorescence labeling was performed with antibodies directed against markers specific to candidate cell types and Fos-like proteins (a marker to identify drug-induced cell activation). We reported here that haloperidol- and clozapine-activated neurons showed the following features: 1) approximately 54-57% of them express dopamine and cyclic AMP-regulated phosphoprotein, 32 kDa (a marker for GABAergic medium spiny projection neurons), 2) they appear rarely to be GABAergic interneurons, marked by the calcium binding proteins, parvalbumin, calretinin or calbindin-D28K, 3) about 84-86% of them express the neuropeptide neurotensin (a neurotransmitter most often associated with projection neurons in the site tested). The results suggest that most of the antipsychotic drug-activated neurons in the shell of nucleus accumbens are likely to be neurotensin containing projection neurons.

A study of neonatal swimming (water therapy) applied in clinical obstetrics

OBJECTIVE

To study the significance of some clinical parameters related to neonatal 'swimming' (water therapy) during hospitalization.

METHODS

Normal newborns were randomly divided into two groups to observe their birth weight, weight before discharge,time of first defecation and meconium turning yellow. Group one was the swimming (study) group, comprising a total of 223 newborns including 127 babies delivered after spontaneous vaginal delivery and 96 babies after Cesarean section. Group two was the bathing (control) group, comprising 154 newborns including 109 babies delivered after spontaneous vaginal delivery and 45 babies after Cesarean section.

RESULTS

There was no significant difference in birth weight between the two groups (p > 0.05). However, the mean weight before discharge of the babies in the study group was 3.29 + 0.35 and 3.51 + 0.40 kg, spontaneous vaginal delivery vs. Cesarean section, compared with 3.09 + 0.38 and 3.17 + 0.48 kg, respectively, in the control group (p < 0.01). The corresponding mean times of meconium turning yellow were 39.15 + 15.88 and 39.02 + 13.60 h in the study group compared with 48.01 + 19.42 and 55.67 + 25.05 h in the control group. This difference was significant (p < 0.01), as was the difference between the time of first defecation (p < 0.05).

CONCLUSION

Neonatal swimming can accelerate babies' growth in the early stage.

Dynorphinergic GABA neurons are a target of both typical and atypical antipsychotic drugs in the nucleus accumbens shell, central amygdaloid nucleus and thalamic central medial nucleus

Administration of typical and atypical antipsychotic drugs leads to activation of cells in the nucleus accumbens shell, central amygdaloid nucleus, and midline thalamic central medial nucleus, implicating important shared effects of these drugs. However, the exact cell types responding to antipsychotic drugs in the nucleus accumbens shell, central amygdaloid nucleus, and midline thalamic central medial nucleus are unclear. We report here that, in a rat model, the results of studies using double immunofluorescence labeling with antibodies directed against markers specific to candidate cell types suggest that the cells responding to haloperidol and clozapine in all three sites are: 1) neurons, rather than astrocytes; 2) inhibitory GABA neurons, but not acetylcholinergic neurons; and 3) dynorphin-containing GABA neurons, but not M-enkephalin-containing GABA neurons. The present study provides pharmacological evidence, at the cellular level in vivo, that the shared effects of antipsychotic drugs, whether typical and atypical, is activation of dynorphinergic GABA neurons in the nucleus accumbens shell, central amygdaloid nucleus, and midline thalamic central medial nucleus. Alternative ways to modulate dynorphinergic GABA neuronal activity or its target receptors might present an important new avenue for the treatment of schizophrenia and other psychotic disorders.

Novel cytotoxic chelators that bind iron(II) selectively over zinc(II) under aqueous aerobic conditions

To achieve cellular iron deprivation by chelation, it is important to develop chelators with selective metal-binding properties. Selectivity for iron has long been the province of certain oxygen-donor chelators such as desferrioxamine, which target Fe(III) and exploit the strength of a relatively ionic Fe(III)-O interaction. We have been studying novel chelators that possess mechanisms to selectively chelate +2 biometals, particularly tachpyr [N,N',N"-tris(2-pyridylmethyl)-1,3,5-cis,cis-triaminocyclohexane] and derivatives from N,N',N"-trialkylation and pyridine ring alkylation. Metal-exchange and metal-binding competition reactions have been conducted at pH 7.4, 37 degrees C and time periods until no further change was observed (generally 24-48 h). Under anaerobic conditions, tachpyr is strongly selective for iron, binding 95+/-5% Fe(II) versus 5+/-5% Zn(II) in the forms [Fe(tachpyr)](2+) and [Zn(tachpyr)](2+) respectively. Under aerobic conditions, tachpyr complexes Fe(II) more effectively than Fe(III), forming iminopyridyl complexes [Fe(tachpyr-ox-n)](2+) (n=2, 4) by O(2)-induced and iron-mediated oxidative dehydrogenation. Complexes [Fe(tachpyr-ox-n)](2+) are also strongly bound forms of iron that are unaffected by an excess of Zn(II) (75 mol zinc:1 mol iron complex). The preference of tachpyr for iron over zinc under aerobic conditions appears to be hindered by oxidation of Fe(II) to Fe(III), such that the proportions bound are 44+/-10% Fe(II) versus 56+/-10% Zn(II), in the respective forms [Fe(tachpyr-ox-n)](2+) and [Zn(tachpyr)](2+). However, upon addition of the reducing agent Na(2)S(2)O(4) that converts Fe(III) to Fe(II), the binding proportions shift to 76+/-10% Fe(II) versus 24+/-10% Zn(II), demonstrating a clear preference of tachpyr for Fe(II) over Zn(II). Iron(II) is in the low-spin state in [Fe(tachpyr)](2+) and [Fe(tachpyr-ox-n)](2+) (n=2, 4), which is a likely cause of the observed selectivity. N-methylation of tachpyr [giving (N-methyl)(3)tachpyr] results in the loss of selectivity for Fe(II), which is attributed to the steric effect of the methyl groups and a resulting high-spin state of Fe(II) in [Fe(N-methyl)(3)tachpyr)](2+). The relationship of chelator selectivity to cytotoxicity in the tach family will be discussed.

Determination of scopolamine, atropine and anisodamine in Flos daturae by capillary electrophoresis

A capillary electrophoresis method was developed for the separation and determination of tropane alkaloids in Flos daturae plants. Separation was performed on a fused silica capillary(42.1 cm x 50 microm i.d.) at an applied voltage of 20 kV. Scopolamine, atropine and anisodamine were well separated in the buffer of 50 mmol/L phosphate buffer (pH 5.0) containing 20% (v/v) tetrahydrofuran (THF). Beer's law was obeyed in the range of concentration of 2.4-21.8 microg/mL for scopolamine, 4.0-36.0 microg/mL for atropine and 2.6-23.7 microg/mL for anisodamine, respectively, and the correlation coefficients were over 0.999 (n = 6). The developed method was applied for the analysis of herb samples.

[Effects of low energy laser on tooth movement and remodeling of alveolar bone in rabbits]

OBJECTIVE

The aim of this study was to investigate effects of low energy laser on the experimental tooth movement and the remodeling of alveolar bone in rabbits.

METHODS

A total of 42 white rabbits were chosen and randomized into one control group and six experimental groups, with 6 rabbits in each group. After anesthesia with 2% pentobaritone sodium, orthodontic appliances consisting of a coil spring connected bilaterally the upper first molar with the upper incisor by using a ligature wire. The force exerted at the time of insertion was approximately 80 g. The left side served as the control side, and the right side was the experimental side treated by receiving irradiation of low energy laser. The treatment periods of different groups lasted separately for 1, 3, 5, 7, 14, 21 days respectively. The displacement extent of teeth was measured by employing the computer image analyzing system. The results were analyzed statistically. Through HE staining, the histomorphological character of tissue around first molar was also investigated, and numbers of osteoclasts were counted.

RESULTS

The displacement extent of teeth on the experimental side, which was irradiated by low energy laser, was more obvious than that of the normal control side. The difference was statistically significant 1, 3, 14, 21 days after the beginning of the treatment. Through histological observation under a light microscope, the osteoclasts and osteoblasts on the experimental side remained more active than those of the control side. There is significant difference in amount of osteoclasts between the experimental and the control sides, 3, 5 or 7 days after the treatment (P < 0.01, P < 0.05).

CONCLUSION

The irradiation of low energy laser promote tooth movement and remodeling of alveolar bone.

Integration of advanced process control and full-scale dynamic simulation

In the process control industry, multivariable model predictive controller and dynamic simulation for operator training are usually available in separate packages. It is very difficult for the operators and plant engineers to find good tools for them to get trained in multivariable advanced process control. This paper presents a system, which integrates the advanced process control and full-scale dynamic simulation. The advanced process control uses multivariable model predictive control techniques. The model used in the predictive control algorithms is generated from the dynamic simulated process. The advanced process controller can control the simulated plant directly, or through a DCS system to control the simulated plant. The combined system provides an excellent environment for training operators in process operation with multivariable advanced process control. The same environment is also very useful for engineers in designing and tuning the advanced process controllers, and in testing communication between the advanced process controller and the DCS systems, or the other type of process control systems.

Adaptive enhancement and kinetics of nucleotide excision repair in humans

An adaptive response, low doses of a mutagen rendering cells more able to subsequently cope with higher doses of that or a related challenging mutagen, enhances nucleotide excision repair in human fibroblasts. After fibroblasts were flashed with 20 J/m2 of UVC, the cyclopyrimidine dimer frequency at any single dinucleotide position remained unchanged for several hours before abruptly displaying first order kinetics of repair. These kinetics were determined by ligation-mediated PCR along exon 9 of the human p53 gene. When a chronic dose of quinacrine mustard (QM) preceded the UVC challenge, the duration of the cyclobutane pyrimidine dimer (CPD) repair lags were reduced by a factor of three and the kinetic half-lives for CPD repair were reduced by a factor of three. The observed repair kinetics are consistent with the following model. The UVC dose required (K(m)) to generate a substrate concentration which half-saturates the cell's repair capacity is 3 J/m2 for the high affinity (6-4) photoproducts and greater than 100 J/m2 for the low affinity cyclobutane dimers. After 20 J/m2 of UVC, the repair enzyme is saturated with (6-4) photoproducts; these competitively inhibit CPD repair by binding all available repair enzyme. After the (6-4)s are repaired, the CPD concentration is less than K(m)(CPD) and so CPD repair kinetics initiate with first order kinetics. QM-induced enhancement, by increasing the concentration, Vmax, of repair enzyme, shortens the duration of (6-4) saturation and increases the rate constant for cyclobutane dimer repair. The data exactly fit the expectations from Michaelis kinetics. Transcription coupled repair is less amenable to Michaelis interpretations and enhanced global repair was almost as rapid as the slightly enhanced transcription coupled repair. We infer that repair enhancement is unable to proportionally increase the number of matrix attachment sites necessary for transcription coupled repair. Understanding competitive inhibition between adduct classes and adaptive enhancement of Vmax is important to understanding the effects of high doses of mutagen mixtures.

The C-terminal fragment of the precursor tail lysozyme of bacteriophage T4 stays as a structural component of the baseplate after cleavage

Tail-associated lysozyme of bacteriophage T4 (tail lysozyme), the product of gene 5 (gp 5), is an essential structural component of the hub of the phage baseplate. It is synthesized as a 63-kDa precursor, which later cleaves to form mature gp 5 with a molecular weight of 43,000. To elucidate the role of the C-terminal region of the precursor protein, gene 5 was cloned and overexpressed and the product was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting, analytical ultracentrifugation, and circular dichroism. It was shown that the precursor protein tends to be cleaved into two fragments during expression and that the cleavage site is close to or perhaps identical to the cleavage site in the infected cell. The two fragments, however, remained associated. The lysozyme activity of the precursor or the nicked protein is about 10% of that of mature gp 5. Both the N-terminal mature tail lysozyme and the C-terminal fragment were then isolated and characterized by far-UV circular dichroism and analytical ultracentrifugation. The latter remained trimeric after dissociation from the N-terminal fragment and is rich in beta-structure as predicted by an empirical method. To trace the fate of the C-terminal fragment, antiserum was raised against a synthesized peptide of the last 12 C-terminal residues. Surprisingly, the C-terminal fragment was found in the tail and the phage particle by immunoblotting. The significance of this finding is discussed in relation to the molecular assembly and infection process.

Heterogeneous repair of N-methylpurines at the nucleotide level in normal human cells

Base excision repair rates of dimethyl sulfate-induced 3-methyladenine and 7-methylguanine adducts were measured at nucleotide resolution along the PGK1 gene in normal human fibroblasts. Rates of 7-methylguanine repair showed a 30-fold dependence on nucleotide position, while position-dependent repair rates of 3-methyladenine varied only sixfold. Slow excision rates for 7-methylguanine bases afforded the opportunity to study their excision in vitro as a model for base excision repair. A two-component in vitro excision system, composed of human N-methylpurine-DNA glycosylase (MPG protein) and dimethyl sulfate-damaged DNA manifested sequence context-dependent rate differences for 7-methylguanine of up to 185-fold from position to position. This in vitro system reproduced both the global repair rate, and for the PGK1 coding region, the position-dependent repair patterns observed in cells. The equivalence of in vivo repair and in vitro excision data indicates that removal of 7-methylguanine by the MPG protein is the rate-limiting step in base excision repair of this lesion. DNA "repair rate footprints" associated with DNA glycosylase accessibility were observed only in a region with bound transcription factors. The "repair rate footprints" represent a rare chromatin component of 7-meG base excision repair otherwise dominated by sequence-context dependence. Comparison of in vivo repair rates to in vitro rates for 3-methyladenine, however, shows that the rate-limiting step determining position-dependent repair for this adduct is at one of the post-DNA glycosylase stages. In conclusion, this study demonstrates that a comparison of sequence context-dependent in vitro reaction rates to in vivo position-dependent repair rates permits the identification of steps responsible for position-dependent repair. Such analysis is now feasible for the different steps and adducts repaired via the base excision repair pathway.

Repair of DNA alkylation damage

Alkylation damage of DNA is one of the major types of insults which cells must repair to remain viable. One way alkylation damaged ring nitrogens are repaired is via the Base Excision Repair (BER) pathway. Examination of mutants in both BER and Nucleotide Excision Repair show that there is actually an overlap of repair by these two pathways for the removal of cytotoxic lesions in Escherichia coli. The enzymes removing damaged bases in the first step in the BER pathway are DNA glycosylases. The coding sequences for a number of methylpurine-DNA glycosylases (MPG proteins) were cloned, and a comparison of the amino-acid sequences shows that there are some similarities between these proteins, but nonetheless, compared to other DNA glycosylases, MPG proteins are more divergent. MPG proteins have been purified to homogeneity and used to identify their substrates ranging from methylating agents to deamination products to oxidatively damaged bases. The ligation-mediated polymerase chain reaction has been used to study the formation of alkylation damage, and its repair in mammalian cells. We have studied DNA damage in the PGK1 gene for a series of DNA alkylating agents including N-methyl-N'-nitro-N-nitrosoguanidine, Mechlorethamine, and Chlorambucil and shown that the damage observed in the PGK1 (phosphoglycerate kinase 1) gene depends on the alkylating agent used. This report reviews the literature on the MPG proteins, DNA glycosylases removing 3-methyladenine, and the use of these enzymes to detect DNA damage at the nucleotide level.

Repair of DNA alkylation damage

Alkylation damage of DNA is one of the major types of insults which cells must repair to remain viable. One way alkylation damaged ring nitrogens are repaired is via the Base Excision Repair (BER) pathway. Examination of mutants in both BER and Nucleotide Excision Repair show that there is actually an overlap of repair by these two pathways for the removal of cytotoxic lesions in Escherichia coli. The enzymes removing damaged bases in the first step in the BER pathway are DNA glycosylases. The coding sequences for a number of methylpurine-DNA glycosylases (MPG proteins) were cloned, and a comparison of the amino-acid sequences shows that there are some similarities between these proteins, but nonetheless, compared to other DNA glycosylases, MPG proteins are more divergent. MPG proteins have been purified to homogeneity and used to identify their substrates ranging from methylating agents to deamination products to oxidatively damaged bases. The ligation-mediated polymerase chain reaction has been used to study the formation of alkylation damage, and its repair in mammalian cells. We have studied DNA damage in the PGK1 gene for a series of DNA alkylating agents including N-methyl-N'-nitro-N-nitrosoguanidine, Mechlorethamine, and Chlorambucil and shown that the damage observed in the PGK1 (phosphoglycerate kinase 1) gene depends on the alkylating agent used. This report reviews the literature on the MPG proteins, DNA glycosylases removing 3-methyladenine, and the use of these enzymes to detect DNA damage at the nucleotide level.

The beta protein of phage lambda binds preferentially to an intermediate in DNA renaturation

Phage lambda encodes two recombination proteins that are required for homologous recombination in a recA- host strain. Of these two recombination proteins, one is an exonuclease whose action on double-stranded DNA produces 3' single-stranded ends; the other, called beta protein, is a DNA binding protein that promotes the renaturation of complementary single strands. The enzymes of phage lambda provide a model for understanding a recombination pathway called "single-strand annealing". Further investigation of the binding of beta protein to DNA has revealed a new mechanism of renaturation. As reported before, beta protein binds directly to single-stranded DNA, but not to double-stranded DNA. However, in the experiments reported here, we observed that beta protein bound more strongly to a presumed intermediate in the renaturation reaction that beta itself catalyzed, and beta thereby protected all of a renatured duplex 83-mer oligonucleotide from nuclease digestion.

[Studies on the performance and applications of chloropropyl bonded silica. I. Separation of disubstituted benzene isomers and prostaglandin epimers]

The performance of chloropropyl bonded silica (CPS) in HPLC and its applications in separation of disubstituted benzene isomers and prostaglandin epimers were studied. The CPS column has high column efficiency and the kinetic curves illustrate it is suitable for fast analysis. The effect of composition and pH value of mobile phase (methanol/water or methanol/20 mmol/L H3PO4-NaOH buffer) on the retention of the solutes were investigated. Generally, the main retention mechanism of solutes was hydrophobic interaction, however there also exited polar adsorption interaction, ion-dipole interaction etc. When the mobile phase condition changed, the main separating mechanism may be changed with CPS column. So, with increasing pH value of mobile phase, the retention of isomers of nitrophenol exhibited a parabolic change. The chromatographic condition was optimized, and the isomers of nitrophenol, aminophenol and toluidine etc. as well as the epimers of 15-methyl-PGF2alpha were separated very well on the column. Moreover, the speed of separation was faster than that in general reversed-phase system. CPS showed to have good stability to heat and solvent and it was also a very stable intermediate to prepare bonded phase with various functional groups.

Expert-novice knowledge of computer programming at different levels of abstraction

Computer programming knowledge can be classified into five levels of abstraction: objective, conceptual, functional, logical, and physical. An experiment was carried out to determine whether the mastering of knowledge at different levels of abstraction changed with the level of skill. Ten experts and ten novices in C computer programming participated in the experiment. The subjects' knowledge at the five levels of abstraction was tested through 20 multiple-choice questions. The experimental results indicated that knowledge differences between experts and novices at an abstract level or a concrete level depended on what abstract or concrete knowledge was implied. Experts had better abstract knowledge than novices at the conceptual and functional levels but not at the objective level. Experts had better concrete knowledge than novices at the physical level but not at the logical level. The classification of computer programming knowledge in levels of abstraction and the experimental results helped in clarifying a general finding from previous studies that experts had better abstract knowledge than novices.

High titers of anti-Epstein-Barr virus DNA polymerase are found in patients with severe fatiguing illness

Forty-one patients with chronic fatigue syndrome (CFS), 76 healthy controls matched with the patient group for age range, sex, race, and socioeconomic class, and 22 symptomatic patients with seasonal affective disorder (SAD) had serum sampled for antibodies against 2 Epstein-Barr virus (EBV) replicating enzymes. Abnormal titers of antibodies were found twice as often in CFS patients as controls (34.1% vs. 17.1%), with SAD patients having an intermediate frequency (27.3%). Stratifying for disease severity sharpened the differences considerably, with the sicker CFS and SAD patients having 52% and 50% abnormal tests, respectively; more mildly afflicted CFS and SAD patients had a frequency of abnormal tests in the normal range. Antibodies to EBV DNA polymerase (DNAP) were the more sensitive of the two tests in that they were positive in all cases but one. These findings suggest that antibodies against EBV DNAP may be a useful marker in delineating a subset of patients with severe fatiguing illness for appropriate treatment trials and for monitoring their outcomes.

Characterization of a novel inhibitor of human DNA polymerases: 3,4,5-tri-O-galloylquinic acid

Various galloyl derivatives of quinic acid were found to be inhibitors of human DNA polymerases. Among them, 3,4,5-tri-O-galloylquinic acid (TGQA) was the most potent inhibitor of DNA polymerase alpha. Under identical conditions, this compound was 60-fold more potent than aphidicolin as an inhibitor of DNA polymerase alpha. The inhibition of DNA polymerase alpha by this compound was not competitive with either the template or any of the deoxynucleoside triphosphates with a Ki of 0.28 microM. Under similar reaction conditions, DNA polymerases beta and gamma were much less sensitive to the effects of these compounds and, in contrast to the effect seen with DNA polymerase alpha, the inhibition of DNA polymerases beta and gamma by TGQA was competitive with respect to the template with Ki values of 44.4 and 7.5 microM respectively. The potency of these compounds against DNA polymerase gamma varied according to the assay conditions used. The inhibition of DNA polymerase gamma by TGQA could be increased substantially by using MnCl2 in place of MgCl2 and by including 50 mM potassium phosphate, pH 7.5, in the assay mixture. DNA polymerase beta was also more sensitive to TGQA when measured with MnCl2. However, potassium phosphate had little, if any, effect on the inhibition by TGQA of either DNA polymerase alpha or beta. DNA polymerase alpha was less sensitive to TGQA when assayed with MnCl2. TGQA was not a potent inhibitor of human KB cell growth in culture, which could be due to its degradation or poor uptake. Nevertheless, this compound could serve as a model for developing antitumor drugs targeted at DNA polymerases.