Extracellular Pgk1 interacts neural membrane protein enolase-2 to improve the neurite outgrowth of motor neurons

Understanding the molecular interaction between ligand and receptor is important for providing the basis for the development of regenerative drugs. Although it has been reported that extracellular phosphoglycerate kinase 1 (Pgk1) can promote the neurite outgrowth of motoneurons, the Pgk1-interacting neural receptor remains unknown. Here we show that neural membranous Enolase-2 exhibits strong affinity with recombinant Pgk1-Flag, which is also evidently demonstrated by immunoelectron microscopy. The 325th-417th domain of Pgk1 interacts with the 405th-431st domain of Enolase-2, but neither Enolase-1 nor Enolase-3, promoting neurite outgrowth. Combining Pgk1 incubation and Enolase-2 overexpression, we demonstrate a highly significant enhancement of neurite outgrowth of motoneurons through a reduced p-P38-T180/p-Limk1-S323/p-Cofilin signaling. Collectively, extracellular Pgk1 interacts neural membrane receptor Enolase-2 to reduce the P38/Limk1/Cofilin signaling which results in promoting neurite outgrowth. The extracellular Pgk1-specific neural receptor found in this study should provide a material for screening potential small molecule drugs that promote motor nerve regeneration.

Mass Measurement of Upper fp-Shell N=Z-2 and N=Z-1 Nuclei and the Importance of Three-Nucleon Force along the N=Z Line

Using a novel method of isochronous mass spectrometry, the masses of ^{62}Ge, ^{64}As, ^{66}Se, and ^{70}Kr are measured for the first time, and the masses of ^{58}Zn, ^{61}Ga, ^{63}Ge, ^{65}As, ^{67}Se, ^{71}Kr, and ^{75}Sr are redetermined with improved accuracy. The new masses allow us to derive residual proton-neutron interactions (δV_{pn}) in the N=Z nuclei, which are found to decrease (increase) with increasing mass A for even-even (odd-odd) nuclei beyond Z=28. This bifurcation of δV_{pn} cannot be reproduced by the available mass models, nor is it consistent with expectations of a pseudo-SU(4) symmetry restoration in the fp shell. We performed ab initio calculations with a chiral three-nucleon force (3NF) included, which indicate the enhancement of the T=1 pn pairing over the T=0 pn pairing in this mass region, leading to the opposite evolving trends of δV_{pn} in even-even and odd-odd nuclei.

First Application of Mass Measurements with the Rare-RI Ring Reveals the Solar r-Process Abundance Trend at A=122 and A=123

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and β-delayed neutron emission probability, P_{1  n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

[Anterior segment OCT-assisted PTK combined with PRK in the treatment of myopia associated with cornea macula: a case report]

Nowadays, myopia morbidity keeps increasing in China. As the improvements of technique and safety in corneal refractive surgeries, an increasing number of patients with refractive error tend to choose these treatments. The 26-year-old woman with myopia in this case, whose UCVA was 0.1 in OD and 0.2 in OS, had corneal macula in the nasal side of the left eye owing to a corneal trauma occurred more than 10 years ago. After sufficient preoperative examinations, FS-LASIK was performed on the right eye and PTK combined with PRK was performed on the left eye. The UCVA was 1.2 in both eyes 3 months postoperatively, and the corneal macula was mostly cleared in the left eye. It is demonstrated that PTK combined with PRK is an effective and safe way to correct the diopter as well as remove the lesions for the lowly or moderately myopic patients accompanied with superficial corneal opacity. (Chin J Ophthalmol, 2021, 57: 614-617).

Poly(U)-specific endoribonuclease ENDOU promotes translation of human CHOP mRNA by releasing uORF element-mediated inhibition

Upstream open reading frames (uORFs) are known to negatively affect translation of the downstream ORF. The regulatory proteins involved in relieving this inhibition are however poorly characterized. In response to cellular stress, eIF2α phosphorylation leads to an inhibition of global protein synthesis, while translation of specific factors such as CHOP is induced. We analyzed a 105‐nt inhibitory uORF in the transcript of human CHOP (huORF^chop) and found that overexpression of the zebrafish or human ENDOU poly(U)‐endoribonuclease (Endouc or ENDOU‐1, respectively) increases CHOP mRNA translation also in the absence of stress. We also found that Endouc/ENDOU‐1 binds and cleaves the huORF^chop transcript at position 80G‐81U, which induces CHOP translation independently of phosphorylated eIF2α. However, both ENDOU and phospho‐eIF2α are nonetheless required for maximal translation of CHOP mRNA. Increased levels of ENDOU shift a huORF^chop reporter as well as endogenous CHOP transcripts from the monosome to polysome fraction, indicating an increase in translation. Furthermore, we found that the uncapped truncated huORF^chop‐69‐105‐nt transcript contains an internal ribosome entry site (IRES), facilitating translation of the cleaved transcript. Therefore, we propose a model where ENDOU‐mediated transcript cleavage positively regulates CHOP translation resulting in increased CHOP protein levels upon stress. Specifically, CHOP transcript cleavage changes the configuration of huORF^chop thereby releasing its inhibition and allowing the stalled ribosomes to resume translation of the downstream ORF.

Competitive binding between Seryl-tRNA synthetase/YY1 complex and NFKB1 at the distal segment results in differential regulation of human vegfa promoter activity during angiogenesis

Vascular endothelial growth factor (VEGF) plays a pivotal role in angiogenesis. Previous studies focused on transcriptional regulation modulated by proximal upstream cis-regulatory elements (CREs) of the human vegfa promoter. However, we hypothesized that distal upstream CREs may also be involved in controlling vegfa transcription. In this study, we found that the catalytic domain of Seryl-tRNA synthetase (SerRS) interacted with transcription factor Yin Yang 1 (YY1) to form a SerRS/YY1 complex that negatively controls vegfa promoter activity through binding distal CREs at -4654 to -4623 of vegfa. Particularly, we demonstrated that the -4654 to -4623 segment, which predominantly controls vegfa promoter activity, is involved in competitive binding between SerRS/YY1 complex and NFKB1. We further showed that VEGFA protein and blood vessel development were reduced by overexpression of either SerRS or YY1, but enhanced by the knockdown of either SerRS or yy1. In contrast, these same parameters were enhanced by overexpression of NFKB1, but reduced by knockdown of nfkb1. Therefore, we suggested that SerRS does not bind DNA directly but form a SerRS/YY1 complex, which functions as a negative effector to regulate vegfa transcription through binding at the distal CREs; while NFKB1 serves as a positive effector through competing with SerRS/YY1 binding at the overlapping CREs.

Highly sensitive and scalable AAO-based nano-fibre SERS substrate for sensing application

Well-ordered periodic nanostructures are excellent substrates for many surface-enhanced Raman spectroscopy (SERS) applications. Conventional fabrication approaches such as high precision electron beam lithography or focused ion beam produce high resolution nano-features with great reproducibility at the expense of low throughput. In this work, a highly sensitive and scalable AAO-nano-fibre (ANF) SERS substrate is demonstrated by optimising the second anodisation time of the standard two-step anodisation of aluminium and performing an additional wet etching step on the resulting AAO substrate. The optimised ANF substrate exhibits SERS sensitivity that surpasses the AAO nanoholes and the metal-film-on-nanoparticles substrates. A detection limit of 0.1 nM is achieved with a signal-to-noise ratio of 2.6-3 using a low excitation power of 0.1 mW. The ANF substrate exhibits an enhancement factor of 9.28 × 106 and a standard deviation of no more than 8%. The results indicate that the highly sensitive and scalable ANF substrate is a promising substrate for commercial SERS application.

Structural and functional 3D mapping of skin tumours with non-invasive multispectral optoacoustic tomography

BACKGROUND

Recent advances in technology have enabled the development of various non-invasive skin imaging tools to aid real-time diagnosis of both benign and malignant skin tumours, minimizing the need for invasive skin biopsy. Multispectral optoacoustic tomography (MSOT) is a recently developed non-invasive imaging tool, which offers the unique capacity for high resolution three dimensional (3D) optical mapping of tissue by further delivering highly specific optical contrast from a depth of several millimetres to centimetres in living tissues. MSOT enables volumetric, spectroscopic differentiation of tissue, both in vivo and in real time, with and without the application of biomarker-specific probes, and is further able of providing spatial maps of skin chromophores, as well as underlying blood vasculature.

METHODS

Three patients with suspicious skin tumours consented to have their lesions imaged with MSOT prior to excision. The histological findings and measurements were compared.

RESULTS

We demonstrated the first in vivo clinical use of MSOT for 3D reconstruction of skin tumours in three patients with good histological correlation.

CONCLUSION

Our findings confirm the potential benefit of the new imaging method in guiding surgical intervention to achieve a more precise excision with better clearance and lower relapse rates. It can also potentially help to shorten the duration of Mohs' micrographic surgery. Further large-scale studies are necessary to ensure correlation between MSOT and histology.

Identification of the Lowest T=2, J^{π}=0^{+} Isobaric Analog State in ^{52}Co and Its Impact on the Understanding of β-Decay Properties of ^{52}Ni

Masses of ^{52g,52m}Co were measured for the first time with an accuracy of ∼10  keV, an unprecedented precision reached for short-lived nuclei in the isochronous mass spectrometry. Combining our results with the previous β-γ measurements of ^{52}Ni, the T=2, J^{π}=0^{+} isobaric analog state (IAS) in ^{52}Co was newly assigned, questioning the conventional identification of IASs from the β-delayed proton emissions. Using our energy of the IAS in ^{52}Co, the masses of the T=2 multiplet fit well into the isobaric multiplet mass equation. We find that the IAS in ^{52}Co decays predominantly via γ transitions while the proton emission is negligibly small. According to our large-scale shell model calculations, this phenomenon has been interpreted to be due to very low isospin mixing in the IAS.

[Genetic analysis for 5 congenital hypothyroidism patients due to dyshormonogenesis]

OBJECTIVE

To analyze molecular characteristics of 5 congenital hypothyroidism (CH) patients due to dyshormonogenesis.

METHOD

We enrolled 5 CH patients due to dyshormonogenesis who were identified in Newborn Screening Center of Guangxi Zhuang Autonomous Region, China. Blood samples were collected from the patients and their parents, and genomic DNA was extracted from peripheral blood leukocytes. All exons of DUOX2, TG, TPO and NIS gene together with their exon-intron boundaries were screened by next-generation sequencing. Specimens from 100 normal controls were tested for these novel variations.

RESULT

No TPO, NIS or TG gene mutations were identified. Direct sequencing of the DUOX2 gene revealed that patient 1 had a compound heterozygote for c. 3340delC and p. R683L, patient 2 was homozygous for p. K530X and patient 3 was a heterozygote for p. E879K. Both biallelic and monoallelic heterozygous mutations in DUOX2 were associated with transient CH. Novel mutations included c. 3340delC and p. R683L, analysis of 100 healthy subjects without thyroid disease did not show the same change.

CONCLUSION

Genetic analysis of TPO, NIS, DUOX2 and TG gene in 5 unrelated CH patients with thyroid dyshormonogenesis revealed two novel DUOX2 mutations, both were biallelic and monoallelic heterozygous mutations in DUOX2 associated with transient CH.

Duplication polymorphisms in exon 4 of κ-casein gene in yak breeds/populations

The objective of this study was to compare 12 bp-duplication polymorphisms in exon 4 of the κ-casein gene among 3 breeds/populations of yak (Bos grunniens). Genomic DNA was extracted from yak blood or muscle samples (N = 211) and a partial sequence of exon 4 of κ-casein gene was amplified by polymerase chain reaction. A polyacrylamide gel electrophoresis assay of the products (169 bp) revealed 2 variants. These variants differed in a 12-bp duplication of the nucleotide sequence corresponding to amino acids 147-150 (Glu-Ala-Ser-Pro) or 148-151 (Ala-Ser-Pro-Glu). The genotype frequency and gene frequency of the 2 κ-casein variants differed among the 3 yak breeds/populations. The long form of the κ-casein gene was the predominant allele, and the Jiulong yak showed the highest frequency of the short form variant of the κ-casein gene. In addition, 2 nucleotide differences resulting in amino acid substitutions were also identified in yaks. These results are significant for designing a breeding strategy to improve the genetic makeup of yak herds.

Zebrafish Dkk3a protein regulates the activity of myf5 promoter through interaction with membrane receptor integrin α6b

Myogenic regulatory factor Myf5 plays important roles in muscle development. In zebrafish myf5, a microRNA (miR), termed miR-3906 or miR-In300, was reported to silence dickkopf-3-related gene (dkk3r or dkk3a), resulting in repression of myf5 promoter activity. However, the membrane receptor that interacts with ligand Dkk3a to control myf5 expression through signal transduction remains unknown. To address this question, we applied immunoprecipitation and LC-MS/MS to screen putative membrane receptors of Dkk3a, and Integrin α6b (Itgα6b) was finally identified. To further confirm this, we used cell surface binding assays, which showed that Dkk3a and Itgα6b were co-expressed at the cell membrane of HEK-293T cells. Cross-linking immunoprecipitation data also showed high affinity of Itgα6b for Dkk3a. We further proved that the β-propeller repeat domains of Itgα6b are key segments bound by Dkk3a. Moreover, when dkk3a and itgα6b mRNAs were co-injected into embryos, luciferase activity was up-regulated 4-fold greater than that of control embryos. In contrast, the luciferase activities of dkk3a knockdown embryos co-injected with itgα6b mRNA and itgα6b knockdown embryos co-injected with dkk3a mRNA were decreased in a manner similar to that in control embryos, respectively. Knockdown of itgα6b resulted in abnormal somite shape, fewer somitic cells, weaker or absent myf5 expression, and reduced the protein level of phosphorylated p38a in somites. These defective phenotypes of trunk muscular development were similar to those of dkk3a knockdown embryos. We demonstrated that the secreted ligand Dkk3a binds to the membrane receptor Itgα6b, which increases the protein level of phosphorylated p38a and activates myf5 promoter activity of zebrafish embryos during myogenesis.

Analysis of antigen epitopes and molecular pathogenic characteristics of the 2009 H1N1 pandemic influenza A virus in China

In order to further predict the epidemic trend and develop vaccines for 2009 H1N1 virus, we monitored its epitopes and molecular pathogenic characteristics during the epidemic process. We also analyzed the similarity of antigenic and genetic characteristics among the novel 2009 H1N1, representative seasonal H1N1 strains, and vaccine strains. 2009 H1N1 isolates had high similarity of hemagglutinin (HA) antigenic sites with H1N1 viruses isolated before 1940 and up to 80.0% similarity with 1918 H1N1. The elderly people born before 1940 have relatively low 2009 H1N1 infection rate, which might be responsible for their previous infection with either 1918 H1N1 virus or an early progeny. Compared to seasonal H1N1 vaccine strains from 1999 to 2010, the HA, neuraminidase (NA), and nucleoprotein (NP) proteins of the isolates had highly conserved CTL epitopes (60.5-65.8%, 69.6-82.6%, and 76.7%, respectively). The seriousness and mortality rate of 2009 H1N1 infections were similar to seasonal influenza, which may be related to the molecular characteristics of low toxicity of 2009 H1N1 and cross-T-cell immunity, due to vaccination or exposure to seasonal H1N1 virus. Some strains of 2009 H1N1 acquired mutations at antigenic and glycosylation sites. It is of particular interest that Haishu/SWL110/10 and Beijing/SE2649/09, isolated after November 2009, gained a new glycosylation site at the position 179 of HA protein, near the RBD. Thus, in the future, vaccination with glycosylated 2009 H1N1 virus may prevent the seasonal epidemic caused by strains with glycosylation site mutation near the receptor binding domain (RBD).

The relationship between acid-suppressing drugs and phytobezoar formation: a retrospective analysis and discussion of phytobezoar formation

OBJECTIVES

Although phytobezoars are a rare cause of gastrointestinal obstruction, they are most commonly found in patients with previous gastric surgery. It is well known that predisposing factors of phytobezoar formation are ingestion of fruits containing soluble tannin, presence of dilute hydrochloric acid in the stomach, and gastric stasis or delayed emptying. We investigated whether intake of acid-suppressing drugs that neutralize gastric acidity or inhibit gastric acid secretion to constitute a hypo-acidic condition, increases the risk of phytobezoar formation.

MATERIALS AND METHODS

Between September 1992 and October 2008, 32 patients (24 male and 8 female) with gastrointestinal phytobezoars were diagnosed either surgically or endoscopically at the Tri-Service General Hospital, Taipei, Republic of China. The data were collected from hospital records and analyzed retrospectively.

RESULTS

Eighteen (56.25%) of all patients had previous gastric surgery and 6 (42.9%) of the 14 patients who had not undergone surgery had diabetes mellitus. The majority of admissions were during winter and spring (between October and March) (P < 0.01) and none of the patients had taken acid-suppressing drugs during the 6 months before detection of gastrointestinal phytobezoars.

CONCLUSIONS

In our study, intake of acid-suppressing drugs did not increase the risk of phytobezoar formation in patients with normal gastric motility. Moreover, we believe that the major factor in phytobezoar formation is gastric stasis or delayed emptying, which sufficiently prolongs the retention period of materials in the stomach, while dilute hydrochloric acid is a minor factor.

Monitoring and evaluation of removal of pathogens at municipal wastewater treatment plants

The concentrations and removal of Cryptosporidium, Giardia, and microbial indicators, including somatic coliphages and fecal coliforms were investigated through the wastewater treatment processes at three municipal wastewater treatment plants in Beijing, China. The experimental results showed that the concentrations of Cryptosporidium in untreated wastewater, primary treatment effluent, secondary treatment effluent, tertiary treatment effluent were 33-600, 67-333, 0-9 and 0-0.4 oocysts L(-1), and that of Giardia were 130-3,600, 533-2,033, 0-32 and 0-2.1 cysts L(-1), respectively. The reduction ratios of Cryptosporidium and Giardia by the primary treatment process were 0.12 log and 0.18 log, respectively. Oxidation ditch process had higher reduction efficiency to Cryptosporidium and Giardia than anaerobic-anoxic-oxic process and conventional activated sludge process, probably because of longer retention time and higher sludge concentration. Membrane ultrafiltration had a notably better efficiency to reduce microorganisms, especially Cryptosporidium and Giardia, than conventional flocculation sedimentation and sand filtration process, as the tertiary treatment. Comparing with total coliforms, fecal coliforms and heterotrophic bacteria, concentration of somatic coliphages was correlated better with that of Cryptosporidium and Giardia in untreated wastewater and secondary treatment effluent.

Constitutive expression of human angiostatin in Pichia pastoris by high-density cell culture

A high-density cell culture method to produce human angiostatin has been successfully established by constitutive expression of the protein in Pichia pastoris. The fermentation was carried out in a 20 l bioreactor with a 10 l working volume, using a high-density cell culture method by continuously feeding with 50% glycerol-0.8% PTM4 to the growing culture for 60 h at 30 degrees C. Dissolved oxygen level was maintained at 25-30% and pH was controlled at 5 by the addition of 7 M NH4OH. Angiostatin was constitutively expressed during the fermentation by linking its expression to the P. pastoris constitutive GAP promoter (pGAP). But after 36 h of fermentation, the peak biomass growth was 305 as measured by absorption of 600 nm, while the peak angiostatin expression was 176 mg/l. Similar to the product expressed from inducible system [24], angiostatin produced from constitutive system also inhibited the angiogenesis on the CAM and suppressed the growth of B16 melanoma in C57BL/6J mouse. The above results suggest that GAP promoter is more efficient than AOX1 promoter for the expression of angiostatin in P. pastoris by shake flask culture or high-density cell fermentation and is likely to be an alternative to AOX1 promoter in large-scale expression of angiostatin and other heterologous proteins.

Subnanosecond-resolution phase-resolved fluorescence imaging technique for biomedical applications

Characterization of fluorescence emissions from cells often leads to conclusive results in the early detection of cellular abnormalities. Cellular abnormalities can be characterized by their difference in the fluorescence lifetime, which may be less than nanoseconds. A sensitive frequency domain technique, also called a phase-resolved fluorescence imaging technique, is proposed in which fluorescence emissions at the same wavelengths can more effectively be separated with subnanosecond resolution in their lifetime difference. The system configuration is optimized by incorporating even-step phase shifting in the homodyne-assisted signal-processing concept along with the phase-resolved fluorescence technique to eliminate the dc offsets of emission. Experiments are carried out with simulated samples composed of two fluorescence emissions of the same wavelength but with different lifetime values. Suppression of either of the fluorescence emissions by selective imaging of the other validates the superiority of the proposed technique. Hence, this technique can potentially be applied in the early detection of cellular abnormalities.

A simple predictive model for blood-brain barrier penetration

A simple two-descriptor model to predict blood-brain barrier penetration is derived from a training set of 79 compounds: log BB = - 13.31V2 + 9.601V - 2.231PSA - 0.5290 (n = 79, r2 = 0.83) where log BB is the logarithm of the ratio of the steady-state concentration of the compound in the brain to in the blood, V (nm3) is the molecular volume, PSA (nm2) is the polar surface area which is defined as the sum of the van der Waals surface areas of oxygen atoms, nitrogen atoms, and attached hydrogen atoms in a molecule, n is the number of compounds, and r is the correlation coefficient. The model is validated by a leave-one-out procedure and an external test set (25 compounds). The results indicate that the model developed is statistically sound and is sufficiently reliable and robust for predictive use. The descriptors in the model can be easily computed and it is suitable for the rapid prediction of the blood-brain barrier penetration for a wide range of drug candidates.

A mathematical model to predict the release of water-soluble drugs from HPMC matrices

A mathematical model to predict the fraction of water-soluble drug released as a function of release time (t, h), HPMC concentration (CH, w/w), and volume of drug molecule (V, nm3) was derived with ranitidine hydrochloride, diltiazem hydrochloride, and ribavirin as model drugs. The model is log (M(t)/M(infinity)) = 0.5 log t-0.3322CH-0.2222V-0.2988 (n = 140, r = 0.9848), where M(t) is the amount of drug released at time t, M(infinity) is the amount of drug released over a very long time, which corresponds in principle to the initial loading, n is the number of samples, and r is the correlation coefficient. The model was validated using isoniazid and satisfactory results were obtained. The model can be used to predict the release fraction of various soluble drugs from HPMC matrices having different polymer levels.

Changes in VP2 gene during the attenuation of very virulent infectious bursal disease virus strain Gx isolated in China

Very virulent (vv) infectious bursal disease virus (IBDV) Gx strain with high pathogenicity was attenuated through replication in specific-pathogen-free (SPF) chicken embryos and in chicken embryo fibroblast (CEF) cell cultures. The changes in VP2 nucleotide and the deduced amino acid sequences were obtained during attenuation of vvIBDV in CEF culture. Sequence analysis of selected passages from numbers 0 to 20 in CEFs (designated here Gx to CEF-20) showed that no changes were detectable in the VP2 gene before CEF-7. There were a few changes in the nucleotide sequence of the VP2 gene but no amino acid substitutions at CEF-8. The virus of CEF-9 was an intermediate with some amino acid changes that possibly were related to virulence. CEF-10 virus had become similar to CU-1 strain. The VP2 gene sequence remained the same from CEF-10 to CEF-20. The results of pathogenicity tests showed that the mortalities of Gx, CEF-5, CEF-8, and CEF-9 in 4-wk-old SPF chickens were 64%, 60%, 60%, and 32%, respectively; whereas CEF-10, CEF-15, and CEF-20 were nonpathogenic. Virus neutralization tests with Gx strain showed that the antigenicities are similar from Gx to CEF-20.

Type III tympanoplasty with cartilage obliteration for cholesteatoma surgery

BACKGROUND

The main objective of cholesteatoma surgery is complete eradication of the disease. Another goal is to preserve hearing acuity. We reviewed type III tympanoplasty with cartilage obliteration for cholesteatomatous ears. To evaluate the role of ossiculoplasty, the functional results of classic and modified type III tympanoplasties were compared.

METHODS

Thirty-six cholesteatomatous ears undergoing type III tympanoplasty with cartilage obliteration were reviewed. The same operator performed these operations from 1984 until 1995. According to the CAO staging system, there were five early, 16 moderate and 15 advanced-stage cases of cholesteatoma. Using the anterior approach, all operations were canal-wall-down type III tympanoplasties with "tailored" open cavity and cartilage obliteration. There were 24 classic and 12 modified type III tympanoplasties.

RESULTS

The average follow-up duration was 7.2 years. Neither recidivistic cholesteatoma nor retraction pocket was observed postoperatively. There was an improvement in atelectatic score after surgery. The mean postoperative air-bone gap (ABG) was 15.8 +/- 10.7 dB and the mean closure of the ABG was 4.0 +/- 14.3 dB. After the disease stage and preoperative hearing status were adjusted using regression analysis, there was no significant difference in hearing results between ears that underwent classic or modified type III tympanoplasties.

CONCLUSIONS

We performed the canal-wall-down tympanoplasty with cartilage obliteration using the anterior approach for treatment of cholesteatoma. Such surgical techniques eradicate the cholesteatoma, prevent its recurrence and create a clean ear. Hearing reconstruction can also be accomplished in a single-stage procedure offering a serviceable hearing acuity.

Decreasing levels of anti-Nef antibody correlate with increasing HIV type 1 viral loads and AIDS disease progression

To study the association between anti-Gag and anti-Nef antibody reactivities and their correlations with disease progression, 174 HIV-1/AIDS patients were followed up for 1 year after they received triple therapy. The antibody reactivities were analyzed using a Western blot test with recombinant Gag and Nef proteins. The results showed that decreasing levels of anti-Gag or anti-Nef antibody correlate with disease progression defined by HIV-1 viral loads or T4 cell counts. After receiving triple treatment for 1 year, 8 of 38 (21.1%) Nef antibody-negative patients became positive, while only 9 of 125 (7.2%) Nef antibody-positive persons lost the antibody reactivity (p < 0.01). Therefore, HIV-1 Nef may serve as a clinical marker of disease progression.

Antibody reactivities to tumor-suppressor protein p53 and HTLV-I Tof, Rex and Tax in HTLV-I-infected people with differing clinical status

Since the presence of anti-p53 antibody has been correlated with the mutation and accumulation of p53, the aim of this study was to detect anti-p53 antibody and understand its correlations with anti-Tof, -Rex, or -Tax antibody reactivity in HTLV-I infected people differing in their clinical status. A plasmid (pGEX-Tof) was constructed to express Tof recombinant protein (RP) in Escherichia coli. Serum samples from 50 asymptomatic carriers (ACs), 50 adult T-cell leukemia (ATL) and 50 HTLV-I-associated myelopathyltropical spastic paraparesis (HAM/TSP) patients were assayed for reactivity with different RPs by Western immunoblotting. The results showed that 2% of ACs, 4% of ATL patients and 6% of HAM/TSP patients had anti-p53 antibody. Therefore, anti-p53 antibody is not a useful serological marker for clinical management of HTLV-I infected people. Only 1 HAM/TSP patient had anti-Tof antibody whose specificity was further confirmed by antibody competition enzyme immunoassay. This study demonstrates that Tof protein is immunogenic in vivo, suggesting that it plays a role in the life cycle and pathogenesis of HTLV-I. The rate of anti-Rex antibody among HAM/TSP patients was significantly higher than that of ACs or ATL patients. In addition, 50% of ACs, 42% of ATL and 98% of HAM/TSP patients had anti-Tax antibody. McNemar's test showed that the presence of anti-p53 antibody did not have any correlation with the anti-Tax antibody in HTLV-I-infected people, while the correlation between anti-p53 and anti-Rex antibodies or anti-p53 and anti-Tof antibodies cannot be ruled out in this study.

The joint action of two mixed stimuli with a bivariate threshold

The general mathematical statistical theory of a mixture of two stimuli in quantal bioassay or other binary response is investigated assuming the existence of thresholds. Univariate thresholds have long been studied. Different serious attempts on bivariate threshold theory have emerged since the late 1940s. Some have been based on biologically established fact mixed with analysis, while others have been more heuristic. In this paper we investigate the properties of correlations of thresholds. Joint actions are then interpreted according to those correlations and deviations from independence. Isoboles are lines, curves, planes, or surfaces of constant probability. They are also investigated, and their properties are used in proofs of important theorems. It is proved that additivity or additivism of two stimuli is present if and only if the thresholds of the two stimuli are perfectly correlated. Furthermore, additivity requires univariate dose-response functions to be everywhere concave on the nonnegative real numbers (doses). Finally, threshold theory, itself, dictates cumulative distributions of marginal thresholds that are everywhere nondecreasing and concave on the nonnegative reals. That is, they cannot have points of inflection. Such popular distributions as the normal and logistic have points of inflection at their respective medians. This does not invalidate their usefulness. They are simply modeling phenomena other than those which are the subject of this paper, namely, threshold theory.

[Improvement of coronary flow by artificial decending the intrathoracic pressure]

In simulating the changes of intrathoracic pressure during deep inhalation, the intrathoracic pressure was descended by repeated aspiration from thoracic cavity in 8 dogs. The volume of coronary flow was observed simultaneously. It was found that when intrathoracic pressure was dropping the coronary flow volume showed an increase as a result of decrease of right atrium pressure and increase of aorta pressure, thus creating an increased pressure difference between inflow and outflow of coronary circulation.

[The characteristic of lymphokine-activated killer cells induced from tumor draining lymph-node cell]

A short time lymphocyte culture for lymphokine activated killer (LAK) cells was presented, the lymphocytes being collected from the tumor draining regional lymph nodes in seven patients with gynecologic malignant tumors. The results showed different cytotoxic activities of LAK cells against Lewis pulmonary cancer cells, CAOV, cells and the new separated ovarian cancer cells. And the cytotoxic activity of the LAK cells increased with the rise of the effecter cell-target cell ratio and maintained at a certain level when the rise of the latter's increase reached a certain extent. The cytotoxic activity of the LAK cells against autologous tumor cells (as from ovarian cancer) were shown to be much stronger than against the others. As the culture days lengthened, the cytotoxicities of the LAK cells from interleukin-2/OKT 3 culture became stronger than from interloukin-2 alone. Large quantities of lymphocytes could be collected from tumor-draining lymphe nodes. This is a preliminary investigation on the inducing of LAK cells from lymphocytes of the draining regional lymph nodes of malignant gynecologic tumors. The quantitative increase of LAK cells and the effect of their cytotoxic activities are to be further explored.

[Urinary gonadotropin fragment measurement in the monitoring of trophoblastic disease]

Urinary gonadotropin fragment (UGF) is a small peptide which is present in the urine of pregnant women and of women with trophoblastic diseases as well as with certain nontrophoblastic malignancies. 275 samples each of urine and blood from 46 patients with trophoblastic diseases were taken for UGF and hCG measurements and compared. 24 samples from 12 healthy, nonpregnant women were taken as control. Cut-off values of UGF and hCG used for measuring the sensitivity of trophoblastic diseases were respectively > 0.2 microgram/L and above 20 micrograms/L. It was found that 64.0% of the urine samples gave UGF values > 0.2 microgram/L and 66.5% of the blood samples showed hCG levels above 20 micrograms/L (P > 0.1). No false-positive rate was observed in the control group. However, among patients who were found to have low or negative hCG values, 57.6% showed positive UGF levels. These findings suggest that in patients with positive levels of both UGF and hCG, the UGF measurement may not be necessary. But for patients with low or negative blood hCG values, certain percentage of urine UGF could still be detected.

[An in vitro and in vivo study of antitumor effects of rHTNF-alpha on human ovarian cancer]

We examined the cytotoxic activities of recombinant human tumor necrosis factor (rHTNF-alpha) and five chemotherapeutic agents, CTX, 5-Fu, VCR, DDP, KSM, against two human ovarian cancer cell lines, OVCAR3 and CAOV3, using the MTT assay. The results showed that cytotoxicities of rHTNF-alpha at 5 x 10-5 x 10(4) u/ml against OVCAR3 cell line for 24 h exposure were from 14.2 +/- 6.8% to 67.2 +/- 3.0%, and those against CAOV3 cell line were from 8.2 +/- 4.3% to 60.9 +/- 1.3%. The cytotoxic effects of all five chemotherapeutic agents against the two cell lines were much lower than that of rHTNF-alpha. Further, we studied the combined anticancer potential of rHTNF-alpha with chemotherapeutic agents against the two cell lines. Various degrees of synergism in cytotoxicities of DDP or KSM in combination with rHTNF-alpha were observed. The cytotoxic effect of rHTNF-alpha on CAOV3 cell were also morphologically observed under phase contrast and electron microscope. Based on experiment in vitro, the in vivo anticancer activity of rHTNF-alpha alone or in combination with KSM was examined against human ovarian cancer OVCAR3 subcutaneously transplanted in nude mice. After 8 weeks of treatment, a statistically significant difference of mean tumor volume was found between the control group and groups that received rHTNF-alpha or rHTNF-alpha plus KSM (P < 0.01).

[Three-dimensional motion of the radial artery and attributes of position, rhythm, shape and variance of pulse diagnosis]

In using the sophisticated colour Doppler image-forming technique, and analysis with the self-made cardioelectric phasic mark fixed point as well as the limb minus/plus pressure bathtub, 44 healthy youths were observed.

THE RESULTS

(1) The superficial arteries in the limbs have their motion forms of radial expansion, axial extension and axis shifting. (2) These three motions, together with the pulsation present periodical changes. (3) Compared with the results on the survey of the topographical autopsy of a cadaver, the scope and forms of aforementioned artery motion were related to the anatomical positions of cadaver in which they were located. (4) The above-mentioned axial position shifting of the arteries constitute the whole body shifting or revolving of the blood vessels through plain observations on two dimensions and provide three-dimensional signals. (5) A systematic study was made between the relationship of the vascular motion pattern in human body and the form attributes of position, rhythm, shape and variance. It is significant to study the individuality of vascular activities as well as to elucidate the mechanism in forming the pulse conditions of TCM.