Occurrence and fate of pharmaceuticals and personal care products in a wastewater treatment plant with Bacillus bio-reactor treatment

Pharmaceuticals and personal care products (PPCPs) have attracted wide attention due to their environmental impacts and health risks. PPCPs released through wastewater treatment plants (WWTPs) are estimated to be 80 %. Nevertheless, the occurrence of PPCPs in the WWTPs equipped with Bacillus spec.-based bioreactors (BBR) treatment system remains unclear. In this study, sludge and waste water samples were collected during separate winter and summer sampling campaigns from a typical BBR treatment system. The results indicate that out of 58 target PPCPs, 27 compounds were detected in the waste water (0.06-1900 ng/L), and 23 were found in the sludge (0.6-7755 ng/g dw). Paraxanthine was the chemical of the highest abundance in the influent due to the high consumption of the parent compounds caffeine and theobromine. The profile for PPCPs in the wastewater and sludge exhibited no seasonal variation. Overall, the removal of target PPCPs in summer is more effective than the winter. In the BBR bio-reactor, it was found that selected PPCPs (at ng/L level) can be completely removed. The efficiency for individual PPCP removal was increased from 1.0 % to 50 % in this unit, after target specific adjustments of the process. The effective removal of selected PPCPs by the BBR treatment system is explained by combined sorption and biodegradation processing. The re-occurrence of PPCPs in the wastewater was monitored. Negative removal efficiency was explained by the cleavage of Phase II metabolites after the biotransformation process, and the lack of equilibrium for PPCPs in the sludge of the second clarifier. A compound specific risk quotient (RQ) was calculated and applied for studying the potential environmental risks. Diphenhydramine is found with the highest environmental risk in wastewater, and 15 other PPCPs show negligible risks in sewage sludge.

Methylated derivatives of polycyclic aromatic hydrocarbons in road dust, green belt soil and parking lot dust: occurrence, spatial distribution and emission sources

Convenient transportation facilities not only bring the higher standard of living to big cities, but also bring some environmental pollution problems. In order to understand the presence and sources of methylated polycyclic aromatic hydrocarbons (Me-PAHs) in environmental samples and their association with total organic carbon (TOC), 49 Me-PAHs were analyzed in road dust, green belt soil and parking lot dust samples in Harbin. The results showed that the ranges of the total Me-PAHs (ΣMe-PAHs) content in road dust were 221-5826 ng/g in autumn and 697-7302 ng/g in spring, and those in green belt soil were 170-2509 ng/g and 155-9215 ng/g in autumn and spring, respectively. And ΣMe-PAHs content in parking lot dust ranged from 269 to 2515 ng/g in surface parking lots and from 778 to 10,052 ng/g in underground parking lots. In these samples, the composition profile of Me-PAHs was dominated by 4-ring Me-PAHs. The results of diagnostic ratios and principal component analysis (PCA) indicated that petrogenic and pyrogenic sources were the main sources of Me-PAHs in the samples. Spearman correlation analysis showed that there was no correlation for Me-PAHs in road dust and green belt soil on the same road. Furthermore, there was a significant positive relationship (0.12 ≤ R2 ≤ 0.67, P < 0.05) between Me-PAHs concentrations and the TOC content. This study demonstrated the presence of Me-PAHs with high concentrations in the road environment samples of Harbin.

Seasonal patterns, fate and ecological risk assessment of pharmaceutical compounds in a wastewater treatment plant with Bacillus bio-reactor treatment

Pharmaceutical compounds (PhCs) pose a growing concern with potential environmental impacts, commonly introduced into the environment via wastewater treatment plants (WWTPs). The occurrence, removal, and season variations of 60 different classes of PhCs were investigated in the baffled bioreactor (BBR) wastewater treatment process during summer and winter. The concentrations of 60 PhCs were 3400 ± 1600 ng/L in the influent, 2700 ± 930 ng/L in the effluent, and 2400 ± 120 ng/g dw in sludge. Valsartan (Val, 1800 ng/L) was the main contaminant found in the influent, declining to 520 ng/L in the effluent. The grit chamber and BBR tank were substantially conducive to the removal of VAL. Nonetheless, the BBR process showcased variable removal efficiencies across different PhC classes. Sulfadimidine had the highest removal efficiency of 87 ± 17% in the final effluent (water plus solid phase). Contrasting seasonal patterns were observed among PhC classes within BBR process units. The concentrations of many PhCs were higher in summer than in winter, while some macrolide antibiotics exhibited opposing seasonal fluctuations. A thorough mass balance analysis revealed quinolone and sulfonamide antibiotics were primarily eliminated through degradation and transformation in the BBR process. Conversely, 40.2 g/d of macrolide antibiotics was released to the natural aquatic environment via effluent discharge. Gastric acid and anticoagulants, as well as cardiovascular PhCs, primarily experienced removal through sludge adsorption. This study provides valuable insights into the intricate dynamics of PhCs in wastewater treatment, emphasizing the need for tailored strategies to effectively mitigate their release and potential environmental risks.

Hollow Plasma Acceleration Driven by a Relativistic Reflected Hollow Laser

In order to address the present difficulty in experimentally generating the relativistic Laguerre-Gaussian laser, primarily due to damage caused to optical modulators, a high-reflectivity phase mirror is applied in the femtosecond petawatt laser system to generate a relativistic hollow laser at the highest intensity of 6.3×10^{19}  W/cm^{2} for the first time. A simple optical model is used to verify that the vortex laser may be generated in this new scheme; using such a relativistic vortex laser, the hollow plasma drill and acceleration are achieved experimentally and proven by particle-in-cell simulations. With the development of the petawatt laser, this scheme opens up possibilities for the convenient production of the relativistic hollow laser at high repetition and possible hollow plasma acceleration, which is important for a wide range of applications such as the generation of radiation sources with orbital angular momentum, fast ignition for inertial confinement fusion, and jet research in the astrophysical environment.

Comparison of Evaluation Results of Different Disability Standards of Long Bone Fracture

Objective To provide reference for further perfection and revision of standards relevant to limb injury by comparing the evaluation results of different disability standards of long bone fracture. Methods Thirty cases were selected from the long bone fracture cases accepted by our institution in 2018. These cases include 5 cases of shoulder, elbow, wrist, hip, knee, ankle joints, respectively, to investigate the degree of loss of function of joints after long bone fracture. Disability evaluation was made according to Classification of the Impairment Related To Injury （hereinafter referred to as Classification）, Assessment for Body Impairment of the injured in road traffic accidents （now repealed, hereinafter referred to as original Road Standard） and Identifying Work Ability-Gradation of Disability Caused by Work-related Injuries and Occupational Diseases （hereinafter referred to as Work Standard）. The disability evaluation results of every domestic standard were compared with the joint damage rate of Guides to the Evaluation of Permanent Impairment （hereinafter referred to as GEPI）. Results The functional loss rate of joints （except ankle） was 26%-48%，and the ankle functional loss rate was 51%-64%. The mean value of GEPI joint impairment rate of the joints was 13%-22%, with the fluctuation range less than 10%. The rate of level 10 disability was 100% according to the Classification. The rate of level 10 disability was 27%, the rate of level 9 disability was 6% and 67% were not disabled according to the original Road Standard. The rate of level 10 disability was 10% according to the Work Standard and 90% had a disability above level 10 （47% were classified as level 7 disability）. Conclusion The people with limb joint dysfunction in this study had evaluation results with a smaller fluctuation range and better consistency according to the Classification and GEPI. The evaluation results according to the original Road Standard and the Work Standard has a less consistency. The Classification is more similar to GEPI and is more reasonable.

A 3-year experience of a simple, novel technique for accurate ostial/non-ostial coronary stenting: The buddy balloon anchor stent technique

OBJECTIVE

To evaluate the safety and efficacy of a new technique for accurate ostial/non-ostial coronary stenting in percutaneous coronary intervention (PCI).

BACKGROUND

Accurate stent localization is a key factor impacting the postoperative success of patients undergoing PCI. However, the accurate localization of some lesions, especially ostial lesions, is very difficult to achieve, because they are often complicated by bobbing or to-and-fro movement of the stent during cardiac contractions.

METHODS

We report a novel technique of precise ostial/non-ostial stenting based on the buddy balloon anchor stent (BBAS) technique. Between May 2014 and July 2017, 47 patients with significant ostial/non-ostial coronary stenosis that required accurate stenting were included in this study. Of them, 23 patients were treated using the conventional method and the remaining 24 patients were treated using (BBAS) technique. Evaluation was then performed using intravascular ultrasound (IVUS) in the procedural, or coronary computed tomography angiography (CCTA) in the follow up.

RESULTS

Using the BBAS technique, the procedural success was achieved in all 24 (100%) cases. IVUS was performed in seven patients (29.17%) and no procedural complications occurred. All six failed cases that occurred among patients with right coronary artery and left anterior descending artery ostial stenosis treated using the conventional method, the lesions were subsequently successfully re-stented using the BBAS technique. After a follow-up of 3-36 months, CCTA was performed in 11 patients (45.83%), all the stents were in the accurate position. There were no major cardiovascular events of death, myocardial infarction, or target lesion revascularization.

CONCLUSION

BBAS is a simple, highly successful and safe technique for accurate stenting of difficult ostial/nonostial coronary stenosis lesions.

Nicotinamide N-methyltransferase as a potential marker for cancer

Cancer is the main leading cause of death in the world, although it has been made noteworthy advances in cancer research in the past decades. Early detection of cancer is extremely important in improving the chances of successful therapy. Thus, it is urgently needed to make further efforts to explore novel tumor markers for treatment. Nicotinamide N-methyltransferase (NNMT) is a cytosolic enzyme which catalyzes the N-methylation of nicotinamide to form 1-methylnicotinamide (1-MNA), and plays an important role in controlling the intracellular concentration of nicotinamide. Nicotinamide, the precursor to NAD+, is an important cofactor that associates cellular redox states with energy metabolism. Growing evidence shows that NNMT protein levels are elevated in a variety of human cancers, and increased NNMT expression has been linked to tumor aggressiveness. This paper presents a review for the role of NNMT expressed in a series of human cancers and the regulating mechanism involved, and offers its potential value of NNMT in cancer detection and treatment.

Collisionless Shock Acceleration of High-Flux Quasimonoenergetic Proton Beams Driven by Circularly Polarized Laser Pulses

We present experimental studies on ion acceleration using an 800-nm circularly polarized laser pulse with a peak intensity of 6.9×10^{19}  W/cm^{2} interacting with an overdense plasma that is produced by a laser prepulse ionizing an initially ultrathin plastic foil. The proton spectra exhibit spectral peaks at energies up to 9 MeV with energy spreads of 30% and fluxes as high as 3×10^{12}  protons/MeV/sr. Two-dimensional particle-in-cell simulations reveal that collisionless shocks are efficiently launched by circularly polarized lasers in exploded plasmas, resulting in the acceleration of quasimonoenergetic proton beams. Furthermore, this scheme predicts the generation of quasimonoenergetic proton beams with peak energies of approximately 150 MeV using current laser technology, representing a significant step toward applications such as proton therapy.

Protective effects of naringin against gp120-induced injury mediated by P2X7 receptors in BV2 microglial cells

This study was aimed at exploring the effects of P2X7 receptors on gp120-induced injury and naringin's protective effects against gp120-induced injury in BV2 microglia. BV2 microglia injury model was established by gp120 treatment and MTS assay was used to verify whether naringin has a cell-protective effect against gp120-induced injury. Changes in P2X7 receptor expression were assayed using RT-PCR, qPCR, and western blot. Results showed that the ODs of the Ctrl, gp120, gp120+naringin, and gp120+BBG groups were 0.91 ± 0.10, 0.71 ± 0.09, 0.83 ± 0.10, and 0.83 ± 0.10, respectively. Compared to the control group, the gp120 group showed a significantly decreased cell survival rate. Cell survival rates of the gp120+naringin group increased significantly compared to those of the gp120 group, while no difference was observed when compared to the gp120+BBG group. The relative P2X7 mRNA expression levels in the Ctrl, gp120, gp120+naringin, and gp120+BBG groups were 0.73 ± 0.06, 1.05 ± 0.06, 0.78 ± 0.05, and 0.81 ± 0.04, respectively. The corresponding P2X7 protein expression levels were 0.46 ± 0.04, 0.79 ± 0.04, 0.38 ± 0.07, and 0.42 ± 0.06. P2X7 mRNA and protein expression in the gp120 group increased significantly compared to those in the control group, and declined in the gp120+naringin group compared to those in the gp120 group. Therefore, P2X7 receptors might be involved in gp120-induced injury in BV2 microglia, and naringin might play a protective role by inhibiting the up-regulated expression of P2X7 receptors.

Magnetism-Driven Ferroelectricity in Double Perovskite Y₂NiMnO₆

We report the discovery of multiferroic behavior in double perovskite Y2NiMnO6. X-ray diffraction shows that the material has a centrosymmetric crystal structure of space group P2(1)/n with Ni(2+)/Mn(4+) ordering. This result is further confirmed by aberration-corrected scanning transmission electron microscopy combined with atomic resolution electron energy loss spectroscopy. The appearance of ferroelectric polarization coincides with the magnetic phase transition (∼67 K), which indicates that the ferroelectricity is driven by magnetism, and this is further confirmed by its strong magnetoelectric (ME) effect. We proposed the origin of the ferroelectricity is associated with the combination of Ni(2+)/Mn(4+) charge ordering and the ↑↑↓↓ spin ordering. When compared with other known magnetic multiferroics, Y2NiMnO6 displays several attractive multiferroic properties, including high polarization (∼145 μC/m(2)), a high multiferroic transition temperature (∼67 K), and strong ME coupling (∼21%).

Mo- and W-based organic nanostructures prepared from bulk crystal isomorphs consisted of [(CH3CH2)3NH)]2[MO2(C14H6O4)2] (M = Mo, W)

Two new crystal isomorphs consisting of complexes [(CH3CH2)3NH)]2[MoO2(C14H6O4)2] (1) and [(CH3CH2)3NH)]2[WO2(C14H6O4)2] (2) have been synthesized, respectively, and from which Mo-based flexible and durable nanopipes with diameters of 16 nm and lengths of hundreds of micrometers and W-based rigid and fragile nanotubules with ununiform diameters ranging from 30 to 100 nm and lengths in tens of micrometers have been prepared separately, which revealed that the change of the metal in the coordination center of the isomorphs can result in obvious variation to their nanostructures. The crystals both exhibited multilayered structures by the piling of lamellar repeating motifs through van der Waals forces, which are formed by the parallel alignment of 1D chains through hydrogen bonds, and the 1D chains are assembled by complexes 1 and 2, respectively, through geometrical intercalation and π-π packing. However, under grinding and ultrasonication, crystal 1 disassembled uniformly into longer and narrower nanostrips, whereas crystal 2 were broken at random into shorter and wider nanoribbons; therefore, the two lamellar nanostructures curled into different cylindrical nanospecies. The differences caused by Mo and W are the following: the Mo complex prefers to assemble into more durable one-dimensional structures along Mo-O bonds than W isomorphs; since Mo-O bonds are weaker than Mo═O and W-O bonds, then the weakest Mo-O bonds can be supported by the adjacent molecules through intercalation and π-π packing, which resulted in that the linkages among the Mo complexes are stronger along the Mo-O direction and hence the longer Mo-based cylindrical structure. Moreover, the flexibility of Mo-based nanopipes and the rigidity of W-based nanotubules might be attributed to that Mo possesses a lower melting point than W; therefore, Mo is softer and W is harsher.

All-optical cascaded laser wakefield accelerator using ionization-induced injection

We report on near-GeV electron beam generation from an all-optical cascaded laser wakefield accelerator (LWFA). Electron injection and acceleration are successfully separated and controlled in different LWFA stages by employing two gas cells filled with a He/O2 mixture and pure He gas, respectively. Electrons with a Maxwellian spectrum, generated from the first LWFA assisted by ionization-induced injection, were seeded into the second LWFA with a 3-mm-thick gas cell and accelerated to be a 0.8-GeV quasimonoenergetic electron beam, corresponding to an acceleration gradient of 187  GV/m. The demonstrated scheme paves the way towards the multi-GeV laser accelerators.

Targeted antisense modulation of inflammatory cytokine receptors

Antisense technology is potentially a powerful means by which to selectively control gene expression. We have used antisense oligonucleotides to modulate the response of the hepatoma cell line, HepG2, to the inflammatory cytokine, IL-6, by inhibiting the expression of its multifunctional signal transducer, gp130. HepG2 cells respond to IL-6 by upregulating acute phase proteins, such as haptoglobin, by five- to tenfold. Gp130 is central to this response, as the upregulation of haptoglobin is almost completely blocked by the addition of high concentrations ( approximately 100 microg/ml) of a monoclonal antibody to gp 130. Antisense oligodeoxynucleotides complementary to the mRNA encoding gp 130 inhibited the upregulation of haptoglobin by IL-6-stimulated HepG2 cells by about 50%. However, a nonsense sequence also inhibited haptoglobin secretion by about 20%. To improve the specificity and efficiency of action, we targeted the antisense oligonucleotides to HepG2 cells using a conjugate of asialoglycoprotein-poly-L-lysine. The targeted antisense reduced the binding of IL-6 to HepG2 cells, virtually eliminating high affinity binding. In addition, it inhibited haptoglobin upregulation by over 70%. Furthermore, the dose of targeted antisense required for biological effect was reduced by about an order of magnitude as compared with unconjugated antisense. These results demonstrate the potential of antisense oligonucleotides as a means to control the acute phase response as well as the need for a greater understanding of the mechanism and dynamics of antisense molecules as they are developed toward therapeutic application.

Effect of bio-treatment on the lipophilic and hydrophilic extractives of wheat straw

Wheat straw, an important papermaking raw material in China, was treated with a white-rot fungus of Phanerochaete chrysosporium ME446, and the lipophilic and hydrophilic extractives from the control and bio-treated samples were analyzed by GC and GC-MS. Bio-treatment of wheat straw could alter the chemical composition of both the lipophylic and hydrophilic extractives. Sugars and phenolic substances such as coniferyl alcohol, 4-hydroxycinnamic acid, 1-guaiacylglycerol and ferulic acid were substantially degraded or consumed by the fungus. More lipophilic substances such as wax, glycerides and steryl esters were degraded into the corresponding components, resulting in much higher concentrations of fatty acids and sterols in the bio-treated samples. Obviously, the bio-treatment of wheat straw was of benefit to pitch control in pulping and papermaking processes, in the view of degradation of the more lipophilic substances. In addition, the bio-treatment could increase the lignin concentration in hot-water extractives of wheat straw.

Therapeutic effects of Sophora moorcroftiana alkaloids in combination with albendazole in mice experimentally infected with protoscolices of Echinococcus granulosus

The objective of the present study was to determine if the combination of alkaloids from Sophora moorcroftiana seeds and albendazole might be effective in the treatment of experimental echinococcosisin female NIH mice (6 weeks old and weighing 18-20 g, N = 8 in each group) infected withprotoscolices of Echinococcus granulosus. Viable protoscolices (N = 6 x 10(3)) were cultured in vitro in 1640 medium and mortality was calculated daily. To determine the in vivo efficacy, mice were inoculated intraperitoneally with viable protoscolices and then treated once daily by gavage for three months with the alkaloids (50 mg kg-1 day-1) and albendazole (50 mg kg-1 day-1), separately and in combination (both alkaloids at 25 mg kg-1 day-1 and albendazole at 25 mg kg-1 day-1). Next, the hydatid cysts collected from the peritoneal cavity of the animals were weighed and serum IL-4, IL-2, and IgE levels were analyzed. Administration of alkaloids to cultured protoscolices showed significant dose- and time-dependent killing effects. The weight of hydatid cysts was significantly decreased upon treatment with each drug (P < 0.01), but the decrease was more prominent and the rate of hydatid cyst growth inhibition was much higher (76.1%) in the group receiving the combined treatments (18.3 +/- 4.6 mg). IL-4 and total IgE were decreased (939 +/- 447 pg/mL and 2.03 +/- 0.42 IU/mL, respectively) in serum from mice treated with alkaloids and albendazole compared with the untreated control (1481 +/- 619 pg/mL and 3.31 +/- 0.37 IU/mL; P < 0.01). These results indicate that S. moorcroftiana alkaloids have protoscolicidal effects and the combination of alkaloids and albendazole has significant additive effects.

Identification and mapping of Rf-I an inhibitor of the Rf5 restorer gene for Cms-C in maize (Zea mays L.)

The restoration of the C-type cytoplasmic male sterility (Cms) has been a common agriculture practice in the production of hybrid seed for many years. In this study, a series of crosses between select sterile and restorer lines, as well as a backcross population of (Cms-C77 x 6233) x 6233, were used to investigate the restoration of C-type Cms. Our results demonstrated that there was an inhibitor of the Rf5 restorer gene. This inhibitor gene, Rf-I, maps to chromosome 7 and is tightly linked with SSR markers, umc2326 and umc2327, at a genetic distance 4.7 and 3.4 cM, respectively. After analyzing our data combined with previous studies, we propose that the restoration of C-type Cms has two dominant genes, Rf4 and Rf5. Rf4 has the ability to restore all genotypes of Cms-C lines; however, there exists an inhibitor for the other restorer gene, Rf5; thus, it can restore only those genotypes of Cms-C lines lacking the Rf-I inhibitor.

Antiepileptic Drug Treatment of Nonconvulsive Seizures Induced by Experimental Focal Brain Ischemia

Nonconvulsive seizures (NCSs) after traumatic and ischemic brain injury are often refractory to antiepileptic drug therapy and are associated with a decline in patient outcome. We recently characterized an in vivo rat model of focal brain ischemia-induced NCS and here sought to evaluate potential pharmacological treatments. Electroencephalographic activity was recorded continuously for 24 h in freely behaving rats subjected to permanent middle cerebral artery occlusion (MCAo). Rats were treated with an antiepileptic drug from one of seven different drug classes at ED(50) and 2x ED(50) doses (as reported in other rat seizure models), delivered as a single i.v. injection 20 min post-MCAo. Vehicle-treated rats (n = 9) had an 89% incidence of NCS with an average number of NCS of 8.6 +/- 1.9. The latency to onset of NCS was 32.5 +/- 3.4 min post-MCAo with an average duration of 49.1 +/- 8.2 s/event. The high doses of ethosuximide, gabapentin, fos-phenytoin, and valproate significantly reduced the incidence of NCS (11, 14, 14, and 38%, respectively), whereas midazolam, phenobarbital, and dextromethorphan had no significant effect at either dose. Across treatment groups, there was a low but significant correlation between the number of NCS events per animal and volume of brain infarction (r = 0.352). Antiepileptic drug therapy that prevented the occurrence of NCS also reduced mortality from 26 to 7%. Based on combined effects on NCS, infarction, neurological recovery, and mortality, ethosuximide and gabapentin were identified as having the best therapeutic profile.

Treatment with the snail peptide CGX-1007 reduces DNA damage and alters gene expression of c-fos and bcl-2 following focal ischemic brain injury in rats

Delayed cell death following ischemic brain injury has been linked to alterations in gene expression. In this study we have evaluated the upregulation of several genes associated with delayed cell death (c-fos, bax, and bcl-2) during the initial 24 h of transient middle cerebral artery occlusion (MCAo) in the rat and the effects of postinjury treatment with the NR2B subunit specific NMDA receptor antagonist CGX-1007 (Conantokin-G, Con-G). C-fos mRNA levels peaked at 1 h postinjury in both cortical and subcortical ischemic brain regions (30-fold increase), remained elevated at 4 h and returned to within normal, preinjury levels 24 h postinjury. The increase in mRNA levels correlated to increased protein expression in the entire ipsilateral hemisphere at 1 h. Regions of necrosis at 4 h were void of C-Fos immunoreactivity with continued upregulation in surrounding regions. At 24 h, loss of C-Fos staining was observed in the injured hemisphere except for sustained increases along the border of the infarct and in the cingulate cortex of vehicle treated rats. CGX-1007 treatment reduced c-fos expression throughout the infarct region by up to 50%. No significant differences were measured in either bcl-2 or bax mRNA expression between treatment groups. However, at 24 h postinjury CGX-1007 treatment was associated with an increase in Bcl-2 immunoreactivity that correlated to a reduction in DNA fragmentation. In conclusion, CGX-1007 effectively attenuated gene expression associated with delayed cell death as related to a neuroprotective relief of cerebral ischemia.

Electroencephalogram analysis and neuroprotective profile of the N-acetylated-alpha-linked acidic dipeptidase inhibitor, GPI5232, in normal and brain-injured rats

We have evaluated the effects of the N-acetylated-alpha-linked acidic dipeptidase (NAALADase) inhibitor, GPI5232 [2-[(pentafluorophenylmethyl)hydroxyphosphinyl]methyl)-pentanedioic acid], to not only decrease brain injury but also to alter the inherent electroencephalographic (EEG) changes observed in a rat model of transient middle cerebral artery occlusion (MCAo). Continuous i.v. infusion of GPI5232 starting 1 h after injury resulted in more than a 50% reduction in brain infarct volume caused by 2 h of MCAo. This effect was dose-dependent and significant even when first treatment was delayed for 2 h post-MCAo. At 24 h post-MCAo, EEG spectral analysis of the injured hemisphere revealed functional improvement in GPI5232-treated rats. Significant recovery in high-frequency EEG power (8-30 Hz) was measured in GPI5232-treated animals in both parietal and temporal brain regions but not in vehicle-treated animals. MCAo-injured rats were also predisposed to developing cortical brain seizures, and GPI5232-treated rats had significantly fewer brain seizures than vehicle-treated animals. In separate experiments, acute high doses of GPI5232 in normal rats did not significantly alter EEG brain activity as evaluated by spectral analysis and did not produce any signs of seizure activity or behavioral abnormalities. These results show GPI5232 to be an effective neuroprotective treatment when given postinjury by reducing brain infarction and ameliorating the pathological EEG associated with focal brain ischemia.

Cysteine metabolism and whole blood glutathione synthesis in septic pediatric patients

OBJECTIVE

To investigate whole body in vivo cysteine kinetics and its relationship to whole blood glutathione (GSH) synthesis rates in septic, critically ill pediatric patients and controls.

DESIGN

Prospective cohort study.

SETTING

Multidisciplinary intensive care unit and pediatric inpatient units at a children's hospital.

PATIENTS

Ten septic pediatric patients and ten controls (children admitted to the hospital for elective surgery).

INTERVENTIONS

Septic patients (age, 31 months to 17 yrs) and controls (age, 24 months to 21 yrs) received a 6-hr primed, constant, intravenous tracer infusion of l-[1-13C]cysteine. Blood samples were obtained to determine isotopic enrichment of plasma cysteine and whole blood [1-13C]cysteinyl-glutathione by gas-chromatography mass spectrometric techniques. The plasma flux and oxidation rate of cysteine and the fractional and absolute synthesis rates of GSH were determined. Septic patients received variable protein and energy intake, as per routine clinical management, and controls were studied in the early postabsorptive state.

MEASUREMENTS AND MAIN RESULTS

Plasma cysteine fluxes were increased in the septic patients when compared with the controls (68.2 +/- 17.5 [sd] vs. 48.7 +/- 8.8 micromol x kg(-1) x hr(-1); p <.01), and the fraction of plasma cysteine flux associated with oxidative disposal was similar among the groups. The absolute rates of GSH synthesis in whole blood were decreased (p <.01) in the septic patients (368 +/- 156 vs. 909 +/- 272 micromol x L(-1) x day(-1)). The concentration of whole blood GSH also was decreased in the septic group (665.4 +/- 194 vs. 1059 +/- 334 microM; p <.01)

CONCLUSIONS

Whole blood glutathione synthesis rates are decreased, by about 60%, in critically ill septic children receiving limited nutritional support. Plasma cysteine fluxes and concentration of cysteine were increased in the septic patients, suggesting a hypermetabolic state with increased protein breakdown. The mechanisms whereby GSH synthesis rates are decreased in these patients are probably multifactorial, presumably involving an inflammatory response in the presence of limited nutritional support. The role of nutritional modulation and the use of cysteine prodrugs in maintaining GSH concentration and synthesis remain to be established.

Arginine and ornithine kinetics in severely burned patients: increased rate of arginine disposal

Arginine serves multiple roles in the pathophysiological response to burn injury. Our previous studies in burn patients demonstrated a limited net rate of arginine de novo synthesis despite a significantly increased arginine turnover (flux), suggesting that this amino acid is a conditionally indispensable amino acid after major burns. This study used [15N2-guanidino-5,5-2H2]arginine and [5-13C]ornithine as tracers to assess the rate of arginine disposal via its conversion to and subsequent oxidation of ornithine; [5,5-2H2]proline and [5,5,5-2H3]leucine were also used to assess proline and protein kinetics. Nine severely burned patients were studied during a protein-free fast ("basal" or fast) and total parenteral nutrition (TPN) feedings. Compared with values from healthy volunteers, burn injury significantly increased 1) fluxes of arginine, ornithine, leucine, and proline; 2) arginine-to-ornithine conversion; 3) ornithine oxidation; and 4) arginine oxidation. TPN increased arginine-to-ornithine conversion and proportionally increased irreversible arginine oxidation. The elevated arginine oxidation, with limited net de novo synthesis from its immediate precursors, further implies that arginine is a conditionally indispensable amino acid in severely burned patients receiving TPN.

Melanocortin-1 receptor gene variants in four Chinese ethnic populations

There is strong relationship between melanocortin-1 receptor (MC1R) gene variants and human hair color and skin type. Based on a sequencing study of MC1R gene in 50 individuals from the Uygur, Tibetan, Wa and Dai ethnic populations, we discuss the occurrence of 7 mc1r variants consisting of 5 nonsynonymous sites (Val60Leu, Arg67Gln, Val92Met, Arg163Gln and Ala299Val) and 2 synonymous sites (C414T and A942G), among which C414T and Ala299Val were reported for the first time. Confirmation and analysis were also made of 122 individuals at three common point mutations (Val92Met, Arg163Gln, A942G) using PCR-SSCP. The frequency of Arg163Gln variant varies in the four ethnic populations, with percentage of 40%, 85.0%, 66.2% and 72.7%, respectively, while those of Val92Met and A942G are roughly similar in these four populations. The different environments, migration and admixture of various ethnic groups in China might have impact on the observed frequency of Arg163Gln.

N-acetylaspartylglutamate protects against transient focal cerebral ischemia in rats

The inhibition of N-acetylated alpha-linked acidic dipeptidase (NAALADase: glutamate carboxypeptidase II) has been previously shown to protect against ischemic injury presumably through mechanisms of decreasing glutamate and increasing N-acetylaspartylglutamate (NAAG). Preventing excessive glutamate release is known to be neuroprotective. However, the role of increased NAAG is not clear. We used a middle cerebral artery occlusion model in rats to investigate the neuroprotective effect of NAAG via its action as a metabotropic glutamate (mGlu) receptor agonist. Rats received intracerebral injections of NAAG (1, 2, or 4 micromol), or a co-injection of NAAG (2 micromol) and the non-selective mGlu receptor antagonist, (R,S)-alpha-methyl-4-carboxyphenylglycine, (MCPG, 2 micromol). Immediately after the treatment, the animals received 2 h of middle cerebral artery occlusion followed by 22 h of reperfusion. Treatment with 1 or 2 micromol of NAAG significantly reduced total infarct volume. Treatment with MCPG partially attenuated the neuroprotective effect of NAAG, indicating that the protective effect of NAAG against ischemic injury may be in part mediated via activation of mGlu receptors.

Blood glutathione synthesis rates in healthy adults receiving a sulfur amino acid-free diet

The availability of cysteine is thought to be the rate limiting factor for synthesis of the tripeptide glutathione (GSH), based on studies in rodents. GSH status is compromised in various disease states and by certain medications leading to increased morbidity and poor survival. To determine the possible importance of dietary cyst(e)ine availability for whole blood glutathione synthesis in humans, we developed a convenient mass spectrometric method for measurement of the isotopic enrichment of intact GSH and then applied it in a controlled metabolic study. Seven healthy male subjects received during two separate 10-day periods an L-amino acid based diet supplying an adequate amino acid intake or a sulfur amino acid (SAA) (methionine and cysteine) free mixture (SAA-free). On day 10, L-[1-(13)C]cysteine was given as a primed, constant i.v. infusion (3 micromol x kg(-1) x h(-1)) for 6 h, and incorporation of label into whole blood GSH determined by GC/MS selected ion monitoring. The fractional synthesis rate (mean +/- SD; day(-1)) of whole blood GSH was 0.65 +/- 0.13 for the adequate diet and 0.49 +/- 0.13 for the SAA-free diet (P < 0.01). Whole blood GSH was 1,142 +/- 243 and 1,216 +/- 162 microM for the adequate and SAA-free periods (P > 0.05), and the absolute rate of GSH synthesis was 747 +/- 216 and 579 +/- 135 micromol x liter(-1) x day(-1), respectively (P < 0.05). Thus, a restricted dietary supply of SAA slows the rate of whole blood GSH synthesis and diminishes turnover, with maintenance of the GSH concentration in healthy subjects.

Oxoproline kinetics and oxoproline urinary excretion during glycine- or sulfur amino acid-free diets in humans

L-5-oxoproline (L-5-OP) is an intermediate in glutathione synthesis, possibly limited by cysteine availability. Urinary 5-OP excretion has been proposed as a measure of glycine availability. We investigated whether 5 days of dietary sulfur amino acid (SAA-free) or glycine (Gly-free) restriction affects plasma kinetics of 5-OP and urinary excretion of L- and D-5-OP in 6 healthy men. On day 6, L-5-[1-(13)C]oxoproline and [3,3-(2)H(2)]cysteine were infused intravenously for 8 h (3 h fast/5 h fed). In a control study (adequate amino acid mixture), plasma oxoproline fluxes were 37.8 +/- 13.8 (SD) and 38.4 +/- 14.8 micromol x kg(-1) x h(-1); oxidation accounted for 85% of flux. Cysteine flux was 47.9 +/- 8.5 and 43.2 +/- 8.5 micromol x kg(-1) x h(-1) for fast and fed phases, respectively. Urinary excretion of L- and D-5-OP was 70 +/- 34 and 31.1 +/- 13.3 micromol/mmol creatinine, respectively, during days 3-5, and 46.4 +/- 13.9 and 22.4 +/- 8.3 micromol/mmol over the 8-h tracer study. The 5-OP flux for the Gly-free diet was higher (P = 0. 018) and tended to be higher for the SAA-free diet (P = 0.057) when compared with the control diet. Oxidation rates were higher on the Gly-free (P = 0.005) and SAA-free (P = 0.03) diets. Cysteine fluxes were lower on the the Gly-free (P = 0.01) and the SAA-free diets (P = 0.001) compared with the control diet. Rates of L-5-OP excretion were unchanged by withdrawal of SAA or Gly for 5 days but increased on day 6 (P = 0.005 and P = 0.019, respectively). Thus acute changes in the dietary availability of SAA and Gly alter oxoproline kinetics and urinary 5-OP excretion.

[Detection of EBV-DNA, EBNA2 and LMP-1 in tumor tissues of han and uygur patients with nasopharyngeal carcinoma in Xinjiang]

OBJECTIVE

To investigate the possible differences of human nasopharyngeal carcinogenesis between Han and Uygur patients in xinjiang.

METHOD

Detection of EBV-DNA, EBNA2 and LMP-1 in tumor tissues of 73 patients (Han 41, uygur 32) with nasopharyngeal carcinoma (NPC) were performed by PCR and immunohistochemistry.

RESULT

Tho positive rate of EBV-DNA, EBNA2 expression was 48.2%(20/41), 43.9% (18/41) in Han and 59.3%(19/32), 43.7%(14/32) in Uygur respectively, no significant difference was found (P > 0.05). Expression of LMP-1 in NPC, in both positive and negative EBV-DNA specimens, was higher in Uygur (78.9%) than that in Han (40%) (P < 0.05),

CONCLUSION

The EBV infection may involve in nasopharyngeal carcinogenesis in xinjiang; the LMP-1 of EBV could be a more critical factor in malignant transformation of normal nasopharyngeal epithelium in uygur people than in han Chinese.

Plasma L-5-oxoproline carbon and nitrogen kinetics in healthy young adults

L-5-oxoproline (OP), an intermediate of the gamma-glutamyl cycle of glutathione synthesis and degradation, may serve as a probe for the state of glutathione kinetics. We explored the whole-body carbon and nitrogen kinetics of OP in five male healthy subjects (75.2 kg; 181 cm; 26 y) after a 5-d adaptation to an adequate L-amino acid-based diet (160 mg N x kg(-1) x d(-1); 188 kJ x kg(-1) x d(-1)), using a crossover design. On day 6 of the diet period, we carried out an 8-h tracer protocol (3 h fast; 5 h fed; 2/3 of daily nitrogen intake) with intravenous infusion of L-[1-(13)C]oxoproline and L-[3, 3-(2)H]cysteine or, in randomized order, on the second occasion, L-[(15)N]oxoproline and L-[3,3-(2)H]cysteine. Plasma OP was isolated by cation exchange and after addition of internal standards (DL-[(2)H(3)]-5-oxoproline; L-[(15)N, U-(13)C(5)]-5-oxoproline; DL-[(2)H(3)]-glutamic acid) derivatized to form TBDMS esters and measured by gas chromatography/mass spectrometry. Plasma OP concentration did not differ between fed and fasted state (fast: 59. 4 +/- 8.3; fed 59.2 +/- 8.9 nmol/mL). (13)C- and (15)N OP flux during the fasted and fed state were 19 +/- 3.6, 21.2 +/- 3.2, and 22.6 +/- 3.9, 25.8 +/- 4.3 micromol x kg(-1) x 30 min(-1), respectively. OP oxidation was 15.6 +/- 3.6 and 17.9 +/- 3.5 micromol x kg(-1) x 30 min(-1), in fasting and feeding, respectively, (P < 0.05). More than 80% of the plasma flux was oxidized. These findings are compared with the published literature on GSH turnover in plasma of human subjects and underscore the need to define more completely the dynamic aspects of glutathione metabolism and of the intermediates of the gamma-glutamyl cycle.

Antisense DNA delivery in vivo: liver targeting by receptor-mediated uptake

Antisense oligodeoxynucleotides coupled to asialoglycoprotein carrier molecules were evaluated in terms of their ability to accumulate preferentially in the liver and thus potentially serve as an important method to regulate liver gene expression.

METHODS

Native and asialo-human alpha-1 acid glycoproteins were derivatized with low molecular weight poly(L)lysine and complexed with an antisense DNA (67 mer) complementary to the 5' end of rat serum albumin mRNA. The asialoglycoprotein antisense complex (conjugate) was characterized with respect to size, stability, and anti-sense loading, and the biodistribution of the conjugate was determined for normal rats at 5 min and 1, 6, and 24 hr after intravenous injection. In vivo stability of the anti-sense asialoglycoprotein complex was also evaluated using double-labeled (32P-antisense and 3H-glycoprotein) preparations.

RESULTS

The results of the conjugate characterization studies demonstrated that at least 30% of the anti-sense DNA dissociated from the carrier after 7 min under chromatographic conditions. When the conjugate was incubated with PBS, MEM or MEM plus 10% FBS for 1 hr at 37 degrees C, about 85% of the antisense DNA was dissociated from the carrier. The results of the biodistribution studies showed that the accumulation of the asialo-glycoprotein anti-sense complex in the liver was rapid and greatly exceeded the accumulation of the sialo-glycoprotein antisense analog or antisense alone.

CONCLUSION

These findings have significant implications for the targeted delivery of therapeutic antisense molecules to the liver.

Coupling of antibody-binding fragments to solid-phase supports: site-directed binding of F(ab')2 fragments

A method to covalently bind antibody fragments, via their carboxyl termini to solid supports, is presented. The strategy involves: (1) reversibly blocking all the accessible carboxyl groups on the antibody molecule with phenylhydrazine, (2) exposing the carboxyl termini of the fragment by enzymatic digestion with pepsin and (3) subsequently coupling the fragment to an appropriate support. Experiments with an anti-bovine serum albumin monoclonal antibody and C-14 phenylhydrazine revealed that the blocking step was nearly completely reversible with a dilute solution of FeCl3. Radioiodinated blocked F(ab')2 fragments were then coupled to an amino-functionalized Sepharose 4B column, and characterized as to their coupling capacity (mass of protein coupled/ml of bead), and antigen-binding activity. The coupling capacity of the blocked fragments was found to be 12%, half the coupling efficiency of unmodified radioiodinated F(ab')2. The antigen-binding capacity (mol antigen bound per mol antibody coupled) for the blocked F(ab')2, on the other hand, was found to be 1.9, which was approx. 3.5-times greater than for the unmodified F(ab')2. Comparisons with other conventional coupling techniques were also made. These preliminary studies suggest that this technique can provide one with the means to obtain more uniform and active populations of immobilized antibody fragments.

Sn-chlorin e6 antibacterial immunoconjugates. An in vitro and in vivo analysis

Monoclonal antibody-Sn-chlorin e6 immunoconjugates were prepared by the site-selective covalent modification of the monoclonal oligosaccharide moiety. By carefully controlling the reaction conditions and introducing triethanolamine groups as axial ligands of the Sn moiety, conjugates with in vivo biodistribution properties similar to underivatized IgG were prepared. By varying the reaction conditions, conjugates were reproducibly prepared with a range of photosensitizer to mAb molar ratios from 1.6 to 10. Based on a competitive inhibition radioimmunoassay, conjugates prepared by this method showed selectivity and binding affinity comparable to the unmodified antibody. The immunoconjugates had only slightly lower singlet oxygen yields than that observed with the Sn-chlorin e6 precursor indicating that negligible aggregation or structural modification of the chromophores occurred during the synthesis process. In vitro cell killing experiments demonstrated that all conjugates possessed significant cytotoxic activity. Biodistribution studies in mice showed that conjugates prepared with axial ligands had significant serum retention 24 h after injection while conjugates prepared without the triethanolamine ligand were much more rapidly cleared. In vivo specificity was demonstrated using rats infected with Fisher immunotype I P. aeruginosa at a site in the left posterior thigh muscle. Target to background ratios exceeded 60 at 120 h after conjugate injection of the specific immunoconjugate, compared to a ratio of only 6 for a non-specific mouse IgG conjugate. Biodistribution patterns at 120 h post injection indicate that the conjugates were both biologically active and structurally intact.

Nonuniform phase distribution in ultrasound speckle analysis. I. Background and experimental demonstration

In some cases, the statistical properties of the phase of ultrasound speckle in B-scan images differ from the uniform distribution characteristic exhibited by the fully developed speckle. This phenomenon has been noted when examining scattering structures with a somewhat regular spacing using wideband pulse excitation. It is shown by computer simulation and experiments on phantoms that when the mean scatterer spacing is equal to multiples of a half wavelength at the reference frequency of the receiver quadrature demodulator, the center of the echo phase distribution, plotted on the complex plane, will shift away from the origin. When the spacing is equal to an odd multiple of a quarter wavelength, the phase distribution will have a figure ;8' shape. By noticing those noncircular phase distributions while changing the demodulation frequency, the mean scatterer spacing can be estimated.

Nonuniform phase distribution in ultrasound speckle analysis. II. Parametric expression and a frequency sweeping technique to measure mean scatterer spacing

For pt.I see ibid., vol.39, no.3, p.352-9 (1992). The existence of regularly spaced scatterers in the range cell of an ultrasonic imaging system results in speckle with a nonuniform phase distribution. Characteristic phase distributions occur at those particular demodulator frequencies at which the spacing is a multiple of one-quarter wavelength. A demodulator frequency sweeping technique for scatterer spacing estimation has been developed that uses parametric expressions of the phase statistics to detect and to identify scatterers with regular spacings. Changes in these parameters separately identify the mean scatterer spacing when it is an even and an odd multiple of the quarter wavelength of the demodulator frequency. This technique has good tolerance for variations in mean scatterer spacing, and has real-time implementation capability.

Intrinsic fluorescence studies of the kinetic mechanism of unfolding of alpha-lactalbumin on weakly hydrophobic chromatographic surfaces

The kinetic mechanism of unfolding of calcium depleted bovine alpha-lactalbumin adsorbed on two weakly hydrophobic chromatographic surfaces, methyl- and ethyl-polyether phases bonded to porous silica, with a solution phase of 3 M ammonium sulfate at pH 6.3, has been determined using intrinsic fluorescence and liquid chromatography (LC). The adsorbent has been packed into quartz flow cells which are used for both fluorescence measurements and as a microcolumn for LC. The LC measurements revealed two peaks for alpha-lactalbumin on both phases, the first being folded and the second unfolded. The rate of unfolding was measured to be 1.75.10(-3) min-1 on the Cl-ether and 7.42.10(-3) min-1 on the C2-ether phase. Fluorescence studies revealed a slow change in emission maximum from ca. 330 nm to 350 nm and a 4-fold increase in intensity for the protein adsorbed on the two supports. Variation of fluorescence intensity at a given wavelength revealed biphasic kinetics in which the rate law on the surface was deduced as F in equilibrium X----U, where F is the folded form, U an unfolded form and X an intermediate. The normalized emission spectra of the three species were calculated and it was found that there was approximately a 20-nm-red shift in the position of the maximum from F to U. The emission maximum for X was close to U on both columns; however, the normalized intensity for X was between F and U. Activation enthalpies and entropies were determined from the temperature dependence of the microscopic rate constants. The formation of the intermediate on the C1-ether phase was entropy driven whereas on the C2-ether phase it was enthalpy driven. Finally, the solution refolding rates of U desorbed from the two supports were found to be identical. The differences observed in the surface kinetics of unfolding on the two supports are related to the hydrophobic differences of the adsorbents.

Conformational effects in the high-performance liquid chromatography of proteins. Further studies of the reversed-phase chromatographic behavior of ribonuclease A

This paper is a continuation of an examination of the conformational effects of ribonuclease A (RNase A) in reversed-phase liquid chromatography. RNase A is a particularly good example of reversible conformational refolding during chromatographic elution. Absorbance ratio measurements with a photodiode-array detector are consistent with a two-state model in which an early eluted broad band is associated with the folded or native state and a late eluted sharp band is associated with an unfolded state. By varying the mobile phase flow-rate while maintaining the mean capacity factor (k') of the protein in gradient elution constant, the apparent rate constant of refolding in the mobile phase was measured and found to be comparable with that reported in the literature. It has been further shown that, as the gradient steepness parameter b or mean k' value is altered, the apparent rate constant also changes, as a result of variation in mobile phase composition. The apparent rate constant as a function of temperature was also found to reach a maximum at 20 degrees C. Based on the results of this model system, it is possible to predict optimum conditions for elution of species with sharp elution peaks when reversible refolding takes place in the column.