[Dual-energy separation imaging on an X-ray direct digital imaging system]

A method of dual-energy separation of bone and soft tissue images of chest based on an X-ray direct digital imaging system has been investigated. In this paper, the optimal thickness of the filter for high energy X-ray beam is discussed. An algorithm of correction of scattered radiation is employed before the separation algorithm. The separated images will be shown in the paper. The result shows that it is possible to use an ordinary broad spectral X-ray beam to acquire the dual-energy images for routine X-ray diagnosis.

[Treatment of carinal resections for primary pulmonary carcinoma]

Threeteen patients of lung cancer of center type underwent carinal resections in our department from January 1985 to December 1996. There were 3 patients, T3N2M0 and 10 patients, T4N2M0. Palliative resections were performed for 3 patients and radical resections, for 10 patients. Carinal resection with right pneumonectomy was done in 3 patients, part carinal resection with right pneumonectomy 6 patients, part carinal resection with left pneumonectomy 1 case, and part carinal resection with right sleeve upper and middle lobectomy 3 patients. There were no operative complications and deaths. The 3-year survival rate was 54% and the 5-year survival rates, 30%. One patient has survived for 8 years. The satisfied results of operative therapy were followed when no lymph node metastesis in mediastinum and mass could be resected.

[Recombinant AAV-LMP-induced LMP specific cytotoxic response to autologous lymphoblastoid cell lines tranformed by Epstein-Barr virus]

Epstein-Barr virus is believed to be controlled in normal host by virus specific cytotoxic T lymphocytes (CTL). Although unable to eliminate EBV from the body, CTL seems to be essential in control of latently infected cells. Infusion of autologous EBV specific CTL, which can be produced in laboratory by separating lymphocytes from patients and stimulating them with EBV antigen, will provide an effective method of preventing and treating EBV-related diseases. We inserted the LMP gene of EB virus into an AAV vector pACP and packed it in Ad2 infected 293 cells by co-transfecting with plasmid Ad8, which produced the recombinant virus rAAV-LMP. The recombinant virus was used to infect stimulating cells and LMP antigen was expressed on the surface of these cells. Then the stimulating cells were irradiated and co-cultured with T lymphocytes. The EBV specific CTLs were obtained. The target cells were autologous LCLs from EBV-transformed B lymphocytes. The CTL activity was assayed by BLT activity method. The result indicated that all the four CTL strains could recognize and kill their target cells. This study has laid the technical basis for us to prevent and treat nasopharyngeal carcinoma in China with molecular biological methods.

A case-control study of diet and lung cancer in northeast China

A case-control study involving interviews with 227 lung-cancer cases and 227 matched hospital controls was conducted in Heilongjiang Province in northeast China to examine the influence of dietary factors on the risk of developing lung cancer. Lung-cancer cases were all incident cases judged to be suitable candidates for tumor removal by surgery. Controls were selected among hospitalized patients with non-neoplastic and non-lung disease. The overall male lung-cancer risks associated with cigarette smoking were similar to those reported in other Chinese studies but quite low compared to risks in Western countries. However, the subjects in this study were relatively young (average age 53.2), had started to smoke on average at a relatively old age (21.3 years), and only smoked an average of 18.7 cigarettes per day. Lung-cancer risk was not strongly associated with any of the nutrients examined, when all cases were compared to all controls. However, the data were suggestive of differences in the relationship of diet to risk among smokers and non-smokers. Cautious interpretation is required because of the wide confidence intervals due to limited sample size. Among the smokers, only higher beta-carotene was associated with estimates suggesting a lowered risk. Among non-smokers, the evidence suggested that increased vegetable consumption might reduce risk, consumption of any fruit might reduce risk but beta-carotene was unrelated to risk. The differences observed in the relationship of diet to lung-cancer risk between Chinese smokers and non-smokers warrant further study.

A preliminary report: effects of zinc and micronutrient repletion on growth and neuropsychological function of urban Chinese children

OBJECTIVE

Zinc is essential for growth and cognition of experimental animals. Past research found zinc repletion improved growth of stunted Chinese children. Therefore we measured effects of zinc repletion on growth and neuropsychological functions of children.

DESIGN

Double-blind randomized controlled treatment trial.

SETTING

Elementary schools in low income districts of Chongqing, Qingdao and Shanghai.

SUBJECTS

Three hundred-seventy-two 6 to 9 year old first graders.

INTERVENTIONS

Treatments were 20 mg zinc, 20 mg zinc with micronutrients, or micronutrients alone. The micronutrient mixture was based on guidelines of the US NAS/NRC. Treatments were assigned to classrooms of 40 or more children each, and administered by teachers 6 days per week for 10 weeks.

MEASURES OF OUTCOME

Changes in knee height and neuropsychological functions.

RESULTS

Zinc alone had the least effect on growth while zinc with micronutrients had the largest effect; micronutrients alone had an intermediate effect. Zinc-containing treatments improved neuropsychological functions, but micronutrients alone had little effect.

CONCLUSIONS

The findings confirm the essentiality of zinc for growth of children, and show, for the first time, the essentiality of zinc for neuropsychological functions of children. In addition, the need for repletion of other potentially limiting nutrients in studies examining the effects of specific nutrients on growth and neuropsychological functions was confirmed.

The use of qualitative questionnaires in patients having and being considered for cochlear implants

Within this study we have examined the particular hearing complaints of patients being considered for a cochlear implant and the specific benefits/shortcomings experienced by implanted patients using open-ended questionnaires. As we expected, the difficulty of hearing general conversation was the most common individual hearing complaint. However, 45% of complaints were concentrated in the 'psychosocial' category, which was significantly higher than that found among general audiological rehabilitation patients. The average number of benefits listed by patients having implants was significantly higher than that of the shortcomings. Moreover, the main benefits listed were focused on the acoustical and psychological factors, e.g. 'environmental sound awareness', 'general conversation easier' and 'feeling of self-confidence'. The main shortcomings were related to the acoustical and practical areas, e.g. hearing difficulty in noisy background, processor being cumbersome.

Conformation of 60-residue peptide fragment from N-terminal of porcine kidney fructose 1,6-bisphosphatase

Limited digestion of fructose 1, 6-bisphosphatase with subtilisin produces an S-peptide with an about 60-residue peptide fragment that is non-covalently associated with the enzyme. The 60-residue peptide fragment consists of the most part of allosteric site for AMP binding. It could be separated from S-protein by gel filtration with a Sephadex G-75 column equilibrated with 9% formic acid. According to X-ray diffraction results the S-peptide consists of two alpha-helices without beta-strand and the alpha-helix content is about 60% in the 60-residue-peptide fragment. When the enzyme is subjected to limited proteolysis with subtilisin, the secondary structure of the enzyme does not show a detectable change in CD spectrum. The CD spectra of the isolated S-peptide were measured under different concentrations. In the absence of GuHCl, S-peptide had 30% alpha-helix and 38.5% turn-like structure but had no beta-strand, suggesting that the N-terminal 60-residue fragment, which is synthesized initially by ribosome, would form a conformation spontaneously similar to that of the isolated 60-residue-peptide, i.e. about 30% alpha-helix and 30% turn-like structure. As the elongation of the peptide chain of the enzyme proceeds, the newly synthesized segment or the final entire enzyme, in turn, affects the conformation of prior peptide segment and adjusts its conformation to the final native state. The content of alpha-helix did not increase as perturbing the conformation of S-peptide by adding ethanol, cyclohexane or a small amount of SDS. On the contrary, the ordered structure was slightly decreased, indicating that the difference of conformations of S-peptide in the isolated form and in the associated protein was not an artifact produced by isolation process.

Effectiveness of electrochemical therapy in the treatment of lung cancers of middle and late stage

OBJECTIVE

To investigate the effect of electrochemical therapy (ECT) in the treatment of middle and late-stage lung cancers.

METHODS

Three hundred and eighty-six cases (287 males md 99 females aged 25-78, with an average age of 51 years) with middle and late-stage lung cancers were treated with ECT. Two hundred and three patients had squamous cell carcinoma, 138 adenocarcinoma and 45 undifferentiated cancer. Diameters of the cancers were respectively 4.0-6.0 cm in 153 cases, 6.1-8.0 cm in 82 cases, 8.1-10.0 cm in 102 cases and over 10.0 cm in 49 cases. In this group, none was at stage I, 103 cases were at stage II, 89 cases at IIIa, 122 cases at IIIb and 72 cases IV. Of the 386 cases, 152 cases (39.4%) also suffered from hypertension, heart disease etc. Anode and cathode platinum electrodes were inserted accurately into the tumour mass. Distance between two electrodes was 2.0-2.5 cm. Electrodes were connected to a special ECT instrument. The current was maintained at 6-8 V and 80-100 mA. One hundred coulombs are used for treating 1 cm diameter of tumour mass.

RESULTS

Of the 386 cases, 99 cases (25.6%) achieved complete remission (CR). 179 cases (46.4%) achieved partial remission (PR), 59 cases (15.3%) had no change (NC) and 49 cases (12.7%) had progression of disease (PD). Effective rate CR + PR) was 72% (278 cases). One to five year survival rates were 86.3%, 76.4%, 58.8%, 39.9% and 29.5%, respectively.

CONCLUSIONS

ECT is easy to use. It is effective, safe, less traumatic and makes patients recover quickly. This is a new and effective method to treat patients with tumours who are inoperable and can not receive chemotherapy or radiotherapy.

[The relationship between environmental concentration and exposure concentration in the airborne dust of workplace]

The authors studied the relationship between environmental concentration and exposure concentration in the airborne dust of workplaces, using instantaneous fixed points sampling and personal wear sampling. The results showed that there was a correlation between two kinds of concentrations in the automatic and man-made packing workplaces (r = 0.9914, 0.9977). A relationship between them in the unsteady workplace was found after analysed by one-accumulated generating operation (1-AGO) (r = 0.9945). The samples of environmental and exposure concentrations could be thought from the same normal distribution, that is, the bivariable random sampling in the normal distribution population. Moreover, the exposure concentration could be estimated by environmental one after 1-AGO in the unsteady workplace of airborne dust.

Metal-catalyzed oxidation of histidine in human growth hormone. Mechanism, isotope effects, and inhibition by a mild denaturing alcohol

Metal-catalyzed oxidation of proteins represents an important pathway of post-translational modification. We utilized human growth hormone (hGH), a protein with a well defined metal-binding site, to study the detailed mechanism of metal-catalyzed oxidation by ascorbate/Cu(II)/O2. Particularly His18 and His21 within the metal-binding site were oxidized, predominantly to 2-oxo-His with the incorporated oxygen originating from molecular oxygen, based on amino acid analysis, tryptic mapping, mass spectrometry, isotopic labeling, and 1H NMR. The anaerobic reduction of a hGH/Cu(II) mixture by ascorbate generated a hGH-Cu(I) complex with NMR spectral features different from those of native hGH and hGH/Cu(II). The anaerobic reaction of this hGH-Cu(I) complex with hydrogen peroxide resulted in the oxidation of His18 and His21, suggesting that a fraction of Cu(I) was bound at the metal-binding site of hGH. Site-specific oxidation of hGH required an intact metal-binding site and could largely (about 80%) be inhibited by the presence of >/=28% (v/v) 1-propanol which appears (i) to perturb the metal-binding site and (ii) to interact with a reactive oxygen species formed at the perturbed metal-binding site. The inhibition by 1-propanol-d7 (CD3CD2CD2OH) was significantly lower than that by 1-propanol-h7 with [residual hGH]1-propanol-h7/[residual hGH]1-propanol-d7 = 1.95 at 30% (v/v) 1-propanol, reflecting a kinetic isotope effect close to that for the reaction of a hydroxyl radical with Calpha-H/D bonds of methanol, suggesting the involvement of a hydroxyl radical-like species in the oxidation of His.

STEP: a family of brain-enriched PTPs. Alternative splicing produces transmembrane, cytosolic and truncated isoforms

The family of striatal enriched phosphatases (STEPs) consists of protein tyrosine phosphatases (PTPs) that are enriched within the central nervous system. Previous biochemical studies have shown that the STEP family includes transmembrane, as well as soluble, cytosolic proteins. We now extend these findings with the isolation and characterization of a new, truncated member of this family, termed STEP38. The cDNA of STEP38 encodes a protein of 346 amino acids with a predicted mobility of 38 kDa. In contrast to the cytosolic variants, it contains two hydrophobic amino acid sequences at its N-terminus, two sequences enriched in Pro, Glu, Asp, Ser and Thr residues (PEST sequences), and two polyproline domains. We have used differential centrifugation, continuous sucrose gradients, and transfection experiments to clarify the subcellular localization of STEP38 within membrane compartments. These experiments suggest that a pool of STEP38 is targeted to membrane compartments of the endoplasmic reticulum. The STEP38 cDNA contains a stop codon upstream of the catalytic phosphatase domain that is normally present in other STEP variants, and enzymatic assays conform that STEP38 is inactive. Thus, the STEP family consists of cytosolic, transmembrane, and truncated isoforms. These findings are similar to what has been found for some members of the protein tyrosine kinase (PTK) family that uses alternative splicing mechanisms to produce active and inactive variants. By analogy with suggested mechanisms of action for the truncated PTKs, inactive STEP isoforms may participate in signaling events by protecting potential substrates from dephosphorylation by other members of this family.

[Titanium plate reconstruction and fixation system for maxillofacial surgery: a synthetic clinical and experimental investigation]

Titanium plate-screw systems for maxillofacial reconstruction and internal fixation were studied including examination of chemical components, measurement of mechanical natures, biomechanical and biological evaluation, in combination with retrospective analysis of 319 cases fixed by means of plate-screw appliances. The results demonstrated that all experimental data have satisfied basically the design and clinical requirements, with the exception of a weaker curve-resistance and fixative stability of miniplate as well as lower surface wear-resistance of pure titanium. So, further improvement is necessary. Additionally, the function classification and indication of plate-screw systems are discussed. The duration and condition of intermaxillary fixation is suggested. The complications and their causes are analysed through comparison among different fixation systems.

Inhibition of 3,3',4,4',5-pentachlorobiphenyl-induced fetal cleft palate and immunotoxicity in C57BL/6 mice by 2,2',4,4',5,5'-hexachlorobiphenyl

3,3',4,4',5-Pentachlorobiphenyl (pentaCB) caused a dose-dependent induction of fetal cleft palate in offspring from pregnant C57BL/6 mice exposed to a single dose (783 or 1044 micrograms/kg) of this compound on gestation day 10. In contrast, 2,2',4,4',5,5'-hexaCB did not cause cleft palate at a dose of 271 mg/kg and, in pregnant mice cotreated with 2,2',4,4',5,5'-hexaCB (271 mg/kg) plus 783 or 1044 micrograms/kg 3,3',4,4',5-pentaCB, fetal cleft palate formation was significantly inhibited. 3,3',4,4',5-PentaCB (6 micrograms/kg) also inhibited the splenic plaque-forming cell (PFC) response and serum IgM levels in C57BL/6 mice treated with the T cell-independent antigen trinitrophenyl-lipopolysaccharide. At doses as high as 72 mg/kg, 2,2',4,4'-5,5'-hexaCB was not immunotoxic; however, in mice cotreated with a immunotoxic dose of 3,3',4,4',5-pentaCB plus different doses of 2,2',4,4',5,5'-hexaCB (18, 36 and 72 mg/kg), there was a dose-dependent inhibition of 3,3',4,4',5-pentaCB-induced immunotoxicity. These non-additive (antagonistic) interactions of prototypical polychlorinated biphenyl (PCB) congeners may be an important consideration in development of a toxic equivalency factor approach for hazard and risk assessment of PCB mixtures.

[Immunologically prepared plasma specimen of albuterol for high performance liquid chromatographic determination]

Immune-affinity method for preparation of sample in plasma is reported in this paper. Albuterol was coupled to bovine serum albumin (BSA) to prepare the antigen and immunized in rabbit to produce the anti-albuterol serum (immune globulin). The anti-albuterol serum was treated with saturated ammonium sulfate solution to obtain the antibody (immune globulin). The antibody was coupled with Sepharose 4B to prepare the immune globulin-affinity column. The plasma containing albuterol was introduced into the column and was rinsed in turn with phosphate buffer and water, and then eluted with methanol. After being concenfrated the sample was analyzed by HPLC with a sillica column (4.6 mm x 200 mm, 5 microm), a mixture of methanol: 2 mol/L ammonium acetate (99.5 : 0.5) as mobile phase with a flow rate of 1.2 mL/min, and fluorecence detector monitoring at lambdaex = 226 nm and lambdaem = 306 nm. The results showed that the immune globulin-affinity column has the characteristic of high purity and high specificity, and it is suitable for the preparation of chromatographic plasma specimen to determine albuterol in plasma. The relationship between peak area ratios and concentration from 2 to 80 microg/L were linear (r=0.998). The extraction recoveries from plasma at concentrations of 2-80 microg/L were 98.8% +/- 7.3%. The RSD for intra-day (n=5) was 5.8% and that for inter-day assay (n=5) was 7.8%.

Inhibition of 3,3',4,4',5-pentachlorobiphenyl-induced chicken embryotoxicity by 2,2',4,4',5,5'-hexachlorobiphenyl

3,3',4,4',5-Pentachlorobiphenyl (pentaCB) caused a dose-dependent induction of chicken embryolethality, malformations, edema, and liver lesions at doses ranging from 0.5 to 12.0 microg/kg. In contrast, no embryotoxicity was observed after treatment with 10, 25, or 50 mg/kg 2,2',4,4',5,5'-hexaCB. In eggs cotreated with 2.0 microg/kg, 3,3',4,4',5-pentaCB plus 10, 25, or 50 mg/kg 2,2',4,4',5,5'-hexaCB, there was significant protection from 3,3',4,4',5-pentaCB-induced embryo malformations, edema, and liver lesions, whereas no inhibition of embryolethality was observed. These results further extend the response-specific nonadditive interactions of binary mixtures of polychlorinated biphenyls (PCBs) and should be considered in the development of approaches for hazard assessment of PCB mixtures and related compounds.

STEP61: a member of a family of brain-enriched PTPs is localized to the endoplasmic reticulum

The STEP family of protein tyrosine phosphatases is highly enriched within the CNS. Members of this family are alternatively spliced to produce both transmembrane and cytosolic variants. This manuscript describes the distinctive intracellular distribution and enzymatic activity of the membrane-associated isoform STEP61. Transfection experiments in fibroblasts, as well as subcellular fractionations, sucrose density gradients, immunocytochemical labeling, and electron microscopy in brain tissue, show that STEP61 is an intrinsic membrane protein of striatal neurons and is associated with the endoplasmic reticulum. In addition, structural analysis of the novel N-terminal region of STEP61 reveals several motifs not present in the cytosolic variant STEP46. These include two putative transmembrane domains, two sequences rich in Pro, Glu, Asp, Ser, and Thr (PEST sequences), and two polyproline-rich domains. Like STEP46, STEP61 is enriched in the brain, but the recombinant protein has less enzymatic activity than STEP46. Because STEP46 is contained in its entirety within STEP61 and differs only in the extended N terminus of STEP61, this amino acid sequence is responsible for the association of STEP61 with membrane compartments and may also regulate its enzymatic activity.

Hearing complaints of patients with King-Kopetzky syndrome (obscure auditory dysfunction)

The hearing complaints in patients with King-Kopetzky syndrome were studied by use of the open-ended hearing problem questionnaire. The main findings are that complaints were commonly focused on the categories of 'live speech' and 'electronic speech' difficulties in patients with King-Kopetzky syndrome, particularly the auditory difficulties of speech in noise and group conversation. However, they reported problems with warning signals significantly less frequently than a control 'audiological rehabilitation' group and the patients studied by Barcham and Stephens (1980). In addition, main psychological problems were related to anxiety (e.g. irritability, nervousness and moodiness) in patients with King-Kopetzky syndrome. The open-ended hearing problem questionnaire appears to be a useful tool that can be used to high-light the speech hearing disability encountered by patients with King-Kopetzky syndrome.

[Effect of xiaopiling granules on the treatment of gastric precancerous changes as detected by image analyzer and electronic microscope]

Therapeutic effect of Xiaopiling Granules on gastric precancerous changes was observed, using image analyzer and electronic microscope. The result indicated that the Granules could efficiently eliminate gastric mucositis, nourish gastric mucosa, soften or restrain dysplasia, ameliorate structure atypism and cell atypism of dysplasia, promote elimination of dysplasia and efficiently ameliorate the ultrastructure of gastric precancerous changes.

[Evaluation of clinical and pathological factors relating to lymph node metastasis in carcinoma of the tongue]

In this paper we adopt various clinical and pathological parameters to evaluate the factors relative to the lymph node metastasis. We are of the view that the TNM classification can not indicate the presence of the lymph node metastasis clearly. When the size of tumor is less than 2.0 cm in diameter there is almost no metastasis. Using computer, we analyse the factors and found that only the depth, pattern of growth and the degree of lymphoid cell infiltration are relative to metastasis. The coincidence is 78.6%.

DNA ploidy, expression of p53 protein and metastatic behaviour of gastric carcinoma

DNA ploidy of 57 gastric carcinomas with metastases (12 liver, 1 adrenal, 4 ovary and 48 lymph node) were measured by flow cytometry. DNA anueploidy was significantly related to liver metastases: 9 out of 12 gastric carcinomas with liver metastases were anueploid (75%) as compared to 13 out of 45 (28.8%) of cases without liver metastases (P < 0.01); the one gastric carcinoma with adrenal metastasis was also anueploid. DNA ploidy was not related to ovarian or lymph node metastases. Another interesting finding was that all of 3 gastric carcinomas with liver metastases which showed a diploid DNA pattern, expressed p53 protein, while all of 3 carcinomas with liver metastases but no p53 protein expression were anueploid. The expression of p53 protein was not related to ovarian metastases. The results suggested that an anueploid DNA pattern and the expression of p53 protein are both objective markers valuable in predicting high risk potential of metastases to the liver, and that the combined detection of these markers can be a most useful method in the follow-up of patients with gastric carcinoma in detecting those at high risk of developing metastases following surgical resection. Also the poorer prognosis of patients with gastric carcinoma showing an anueploid DNA pattern may be related to the development of distant organ metastases through the blood vascular system. Furthermore, the clone of gastric carcinoma cells which accumulate p53 protein or show an anueploid DNA pattern may have a causative role in the development of liver (& adrenal) metastases.

Compact read-only memory with lensless phase-conjugate holograms

A new approach to holographic storage that uses lensless phase-conjugate holograms is proposed and demonstrated. Near-field holography is used for data recording, and a phase-conjugate reference beam is used for data retrieval. The data array can be directly transferred from the storage medium to the sensor without the need for imaging optics. It is shown that large space -bandwidth product holographic images (N x N x 10(6)) with pixel sizes of a few micrometers are feasible with a reasonable-sized recording material.

Spatial Aggregation: Theory and Applications

Visual thinking plays an important role in scientific reasoning. Based on the research in automating diverse reasoning tasks about dynamical systems, nonlinear controllers, kinematic mechanisms, and fluid motion, we have identified a style of visual thinking, imagistic reasoning. Imagistic reasoning organizes computations around image-like, analogue representations so that perceptual and symbolic operations can be brought to bear to infer structure and behavior. Programs incorporating imagistic reasoning have been shown to perform at an expert level in domains that defy current analytic or numerical methods. We have developed a computational paradigm, spatial aggregation, to unify the description of a class of imagistic problem solvers. A program written in this paradigm has the following properties. It takes a continuous field and optional objective functions as input, and produces high-level descriptions of structure, behavior, or control actions. It computes a multi-layer of intermediate representations, called spatial aggregates, by forming equivalence classes and adjacency relations. It employs a small set of generic operators such as aggregation, classification, and localization to perform bidirectional mapping between the information-rich field and successively more abstract spatial aggregates. It uses a data structure, the neighborhood graph, as a common interface to modularize computations. To illustrate our theory, we describe the computational structure of three implemented problem solvers -- KAM, MAPS, and HIPAIR --- in terms of the spatial aggregation generic operators by mixing and matching a library of commonly used routines.

Effects of polyaminocarboxylate metal chelators on iron-thiolate induced oxidation of methionine- and histidine-containing peptides

PURPOSE

Site-specific protein oxidation induced by prooxidant/metal/ oxygen has been recognized as one of the major degradation pathways of protein pharmaceuticals. Polyaminocarboxylate (PAC) metal chelators are commonly employed to prevent metal-catalyzed oxidation, for they sequester metals. However, studies have indicated that iron chelates may still be catalytically active due to their specific coordination geometry. The purpose of this study was to investigate how PAC chelators affect prooxidant/metal/oxygen-catalyzed oxidation of peptides containing histidine (His) and methionine (Met).

METHODS

PACs were applied to a model oxidizing system, dithiothreitol/iron/oxygen, which was shown to promote the oxidation of Met to Met sulfoxide in the two model peptides, GGGMGGG and GHGMGGG.

RESULTS

PAC chelators did not suppress the peptide oxidation but significantly changed the product pattern. In particular, the yield of Met sulfoxide dropped significantly, while a number of other products emerged, including oxidation products from the N-terminus and His (if present). Overall, the oxidation became rather non-selective in the presence of PACs. The oxidation kinetics were significantly accelerated by nitrilotriacetate (NTA), ethylenediaminediacetate (EDDA), and ethylenediaminetetraacetate (EDTA), but they were slowed down by ethyl-enebis(oxyethylenenitrilo)tetraacetate (EGTA) and diethylenetri-aminepentaacetate (DTPA). Meanwhile the PAC chelators were also observed to undergo degradation. Scavengers of hydrogen peroxide or hydroxyl radicals exerted only partial inhibition on the peptide oxidation.

CONCLUSIONS

The results of this study are rationalized by the abilities of PAC chelators (i) to extract iron from potential binding sites of the peptides to impair site-specific oxidation, and (ii) to promote the formation of ROS different from the species formed at the peptide metal-binding sites.

[A study on DNA content and cell cycle phase analysis in endometrial carcinoma]

OBJECTIVE

To study the prognostic value of DNA content, cell cycle phase in endometrial carcinoma.

METHODS

DNA content and cell cycle phase analysis were performed on 100 paraffin-embedded archival specimens from 103 cases of endometrial carcinoma using flow cytometry.

RESULTS

Aneuploidy was found in 71.0% of specimens. The aneuploidy rate in specimens from grade III, deep myometrial invasion and stage III, IV was significantly higher than that in specimens from grade I, nonmyometrial invasion and stage I (P < 0.05 respectively). 5-year survival rate for patients with aneuploidy was 65.9% and for patients with diploidy was 87.6% (P < 0.01). High S-phase fraction (SPF) was associated with high grade, deep myometrial invasion and advanced stage. The mean SPF was 13.4% in the living group and 17% in the dead group. The 5-year survival rate for patients with SPF > 17% was 50.4% and for patients with SPF < 17% was 79.1% (P < 0.01). SPF and stage were the most important prognostic factors in endometrial carcinoma by Cox's proportional hazards model.

CONCLUSIONS

DNA ploidy and SPF were found to be of important prognostic indicators in endometrial carcinoma.

[Detection of lipoarabinomannan-IgG in serum for the diagnosis of pulmonary tuberculosis]

OBJECTIVE

To ascertain the value of lipoarabinomannan-IgG (LAM-IgG) determination in the diagnosis of pulmonary tuberculosis.

METHOD

LAM-IgG in sera obtained from 90 patients with active pulmonary tuberculosis, 53 patients with lung cancer and 30 healthy individuals were detected by using rapid enzyme-linked immunosorbent assay (ELISA).

RESULTS

The positive rate was 82% in tuberculosis group, and the false positive rates were 8% and 3% in cancer group and healthy controls respectively.

CONCLUSION

The results suggested that rapid ELISA and LAM-IgG detection was a useful supplementary tool for diagnosis of pulmonary tuberculosis.

Determinants of speech-hearing disability in King-Kopetzky syndrome

King-Kopetzky syndrome is characterized by auditory disability with a clinically normal hearing threshold. The main reported disability is hearing speech in the presence of background noise. The degrees of speech-hearing disability in patients with King-Kopetzky syndrome have been investigated with the use of the Social Hearing Handicap Index (SHHI), and the relationships between the SHHI scores and a number of physiological, psychoacoustical and psychological factors determined in 109 patients. The significantly higher (worse) SHHI scores in patients with King-Kopetzky syndrome indicate that this group suffer a considerable degree of speech-hearing disability. In our study, the main findings are that some psychological factors, performance of the sentence in noise test and auditory thresholds are significantly correlated with the SHHI scores. We were unable to find any relationships between the SHHI and frequency resolution or EOAEs. In a multiple stepwise regression, somatic anxiety and the performance of the sentence in noise test are the significant predictors of SHHI scores. These two variables appear to be the main determinants of speech-hearing disability in King-Kopetzky syndrome.

Hearing impairment: special needs of the elderly

Within this paper we have considered some of the particular disabilities and handicaps commonly experienced by elderly hearing-impaired people as compared with younger individuals. We examined their ratings of their disability and handicap and found that both disability and handicap increased more rapidly with increasing hearing loss in younger than in older patients. We have finally considered the strategies used by older people to cope with hearing loss and found them more likely to withdraw from difficult listening situations or to interrupt the speaker, but less likely to position themselves to hear better.

[A study on expression of tumor suppressor gene p53 in endometrial carcinoma]

OBJECTIVE

To observe the relationship between suppressor gene p53 expression and endometrial carcinoma.

METHODS

Expression of p53 was studied by immunohistochemistry in paraffin sections from 23 normal endometrium, 44 endometrial hyperplasia and 103 endometrial carcinoma.

RESULTS

Immunohistochemical staining of p53 protein was negative in normal and hyperplastic endometrium but positive in 47.6% of endometrial carcinoma. In endometrial carcinoma, p53 over expression was significantly associated with histologic type, tumor grade, presence of vascular invasion and DNA aneuploidy. The survival rate of patients with p53 expression is significantly lower than that of patients without p53 expression (P < 0.001), the 5-year survival rate is 59.9% and 83.4% respectively. Patients with expression of mutant forms of the tumor suppressor gene p53 products had a 6.34-fold increased risk of death as compared with patients without p53 expression by Cox proportional hazards model.

CONCLUSIONS

Aberrant expression of p53 gene is indicative of aggressive biological behavior and poor survival in endometrial carcinoma.

Studies on the relationship between changes in dietary patterns and health status

In order to study the relationship between dietary composition and health and disease, we investigated retrospectively the changes in diet composition, health status and disease specific mortality of the Shanghai population from 1950 to 1985. The results showed that remarkable changes occurred in dietary composition, health status and disease mortality. The energy from grain products decreased from 80-83% in the 1950s to 68-72% in the 1980s, and the energy from animal foods increased from 6.5-8.5% in the 1950s to 17.5-18.0% in the 1980s. With the changes in dietary composition, notable changes also occurred in the nutritional composition of the diet. From the 1950s to the 1980s, energy from fat was increased from 16.3-20.1% to 24.0-28.0%, and the energy from carbohydrates decreased from 72.0-73.5% to 62.2-65.8%. Almost certainly as a result of the changes in diet, health status and disease mortality also changed. For example, the average height in males of 18-20 years old increased from 164.89 cm in 1955 to 167.33 cm in 1974, and the average life span of males and females increased from 42.0 years and 45.6 years in 1950 to 72.1 years and 76.4 years in 1985, respectively. At the same time, the rank order of mortality causes also changed. Before 1950, the first three causes of death were measles, tuberculosis and senility, but in 1985 they were malignant tumours, cerebrovascular disease, and ischaemic heart disease. In particular, the mortality from ischaemic heart disease is now higher than in Japan. The causes of these changes may be the changes of dietary composition and nutritional composition of diet, although there are other factors. Therefore, changes in dietary composition which maintain or improve life expectancy, yet decrease the burden of chronic non-communicable disease is required.

Identification of two alternatively spliced transcripts of STEP: a subfamily of brain-enriched protein tyrosine phosphatases

A brain-enriched protein tyrosine phosphatase termed STEP46 (striatal enriched phosphatase) was previously isolated and characterized. Immunological studies with a STEP monoclonal antibody recognized several STEP-immunoreactive proteins, and suggested that additional STEP-related polypeptides existed. This study reports the isolation of two alternatively spliced transcripts of the STEP gene. One of these, STEP20 (with a predicted molecular mass of 20 kDa) was further characterized and found to lack the conserved tyrosine phosphatase domain. Northern analysis detected a 2.8 kb STEP20 message in mouse brain. The second alternatively spliced transcript, STEP61, has a 5'-extended open reading frame that encodes a protein with a predicted molecular mass of 61 kDa and contains a single tyrosine phosphatase domain. The exon-intron organization responsible for the novel STEP20 and STEP61 sequences was determined in the mouse STEP genomic DNA. We propose that the original STEP46, along with STEP20 and STEP61, are members of a brain-enriched subfamily of protein tyrosine phosphatases, and that STEP isoforms may have distinct functions within the central nervous system.

[Effects of three kinds of decoction on histopathology of gastric mucosa, gastric pH and the content of bile acid in experimental chronic gastritis in rats]

Experimental chronic gastritis (ECG) models were established in rats by inserting a spring into pyloric canal as well as feeding sodium deoxycholate. An experiment was undertaken to observe the therapeutic effects of three formulas of traditional Chinese medicine "Shipitong", "Ganpingyangwei" and "Weile". The experimental results show that all of the three decoctions can reduce gastric pH and bile acid of the ECG rats and make gastric mucosal histomorphology of these rats change markedly.

Developmental toxicity and structure-activity relationships of chlorophenols using human embryonic palatal mesenchymal cells

The chlorophenols (CPs) comprise a major class of widely distributed and frequently occurring environmental contaminants. Previous studies have demonstrated the adverse effects of CPs on embryonic and fetal development. HEPM (human embryonic palatal mesenchymal) and MOT (mouse ovarian tumor) cell lines have been utilized in complementary bioassays for the detection of teratogens, but not the CPs. In this study, our objectives were 2-fold: (1) to determine if the HEPM assay could be used to complement other bioassay systems of nonhuman origin, i.e., Hydra attenuata (HA) and rat whole embryo culture (WEC), in the evaluation of the developmental toxicity of CPs, and (2) to delineate the ability of the HEPM assay to evaluate structure-activity relationships of pentachlorophenol (C5P), 2,3,4,5-tetrachlorophenol (C4P), 2,3,5-trichlorophenol (C3P), 3,5-dichlorophenol (C2P), 4-monochlorophenol (CP), phenol, and CP derivatives (i.e., acetates, sodium phenates and anisoles). HEPM cells were seeded into each well of a 24-well plate and cultivated for 24 h. The medium was replaced with fresh medium containing various concentrations of test chemicals dissolved in dimethyl sulfoxide (DMSO, 0.1%). After culturing for 72 h, the medium was removed, cells were trypsinized, and cell number determined. The HEPM cell growth inhibition assay demonstrated a linear relationship between the IC50 values of the CPs and degree of chlorine substitution. The IC50 values of C5P, C4P, C3P, C2P, CP, and phenol were 18.8, 21.5, 27.5, 63.0, 150.0 and 470.0 microM, respectively. A clear structure-activity relationship was observed between toxicity of CPs and the degree of chlorine substitution. The rank order of CP toxicity from the HEPM assay (i.e., C5P > C4P > C3P > C2P > CP > phenol) is in excellent agreement with previous in vitro and in vivo studies. However, contrary to published reports, the HEPM assay predicted that all CPs were teratogenic (false positives). These findings suggest that the HEPM cell growth inhibition bioassay may be useful to discriminate between subtle differences in structure-activity and, in combination with other bioassays, might facilitate the rapid detection and prioritization of diverse cytotoxins, including various developmental toxicants. Importantly, conclusions about the teratogenicity of a test chemical (via HEPM testing) should be approached with caution and confirmed with other teratogen-sensitive systems.

[Effects of 3 kinds of decoction on serum gastrin, gastrin cell density and the content of PGE2 of gastric antral mucosa in experimental chronic gastritis in rats]

Experimental chronic gastritis (ECG) models were established in rats by inserting a spring into pyloric canal as well as feeding sodium deoxycholate. An experiment was undertaken to observe the therapeutic effects of three formulas of traditional Chinese medicine "Shipitong" (SPT), "Ganpingyangwei" (GPYW) and "Weile" (WL). The experimental results show that all of the three decoctions can make serum gastrin, gastrin cell density and amount of antral mucosal PGE2 of the ECG rats return to normal levels.

Angle-dependent diffraction efficiency in a thick photorefractive hologram

The diffraction from a thick photorefractive hologram is shown to be angular dependent, which originates mainly from the angle-dependent effective electro-optic coefficient of a photorefractive crystal. The angle dependency of the diffraction causes a nonuniform diffraction over the pixel positions or the spatial frequency contents of a hologram image in a page-oriented holographic system, resulting in a deteriorated reconstructed image. In addition, owing to the angular variations in diffraction, the wavelength-multiplexing scheme should be a better choice than angular one.

[Flow cytometry analysis of 67 squamous cell carcinoma of the tongue]

Flowcytometry was used to measure the DNA content in 67 cases with squamous cell carcinoma of the tongue. The relationship of FCM resulte are compared with clinical and pathological parameters. The results show that the recurrences are always appeared within 2 years after operation. Therefore, it is important to follow up patient for the first 2 years after operation. 75% of recurrences are aneuploidy. With multiple statistic analysis, only the clinical stage and aneuploidy are related to lymph node metastasis. The close relative factors to recurrence of SCCT are clinical stage, lymph node metastases, DI value and DNA ploidy.

[Progress report on a World Bank loan to China for a tuberculosis control project]

The progress of the World Bank loaned TB control project implemented from the second quarter of 1991 to the fourth quarter of 1993 was described in this paper. In the past three years, 737 counties of the 12 provinces with the population of 360 million has been covered by the project. Among 95176 new smear positive cases discovered, 93909 patients received free treatment of TB. The treatment coverage is 98.7%, of which 95% were treated under full course supervision. The smear conversion rate at two, three months of new smear positive TB patients are 83.4% and 90.6% respectively. The cohort analysis showed that the cure rate is 89.8%, which has reached the advanced level of the modern national tuberculosis control programme in the world.

Expression of cDNA fragment encoding sperm membrane peptide in E. coli

A secretory high-level expression cloning vector designated as pSBC-20 was constructed by inserting a DNA fragment encoding the signal peptide of ompA protein into pBV 220 vector. Any foreign DNA fragment can be inserted into the polylinker cloning sites located after the secretion signal sequence. The cloned foreign gene is under the control of the PR-PL promoter while the expression of the gene is regulated by the cI-gene product. The products are secreted into the periplasmic space of bacteria or into the medium. A recombinant plasmid (pRSD-220) was constructed by inserting the 210 bp from RSD-2, a cDNA encoding a peptide fragment of human sperm protein, into the EcoRI site of pSBC-20. The E. coli cells transformed with pRSD-220 were propagated at 30 degrees C, then incubated at 42 degrees C for several hrs. The cloned gene product was secreted into the culture medium at a high rate. The yield was about 60 mg of gene product per liter of cultured medium.

[Effect of xiaopiling granules on muscular histochemistry of gastric precancerous changes in rats]

The effect of Xiaopiling Granules on muscular histochemistry of gastric precancerous changes in rats was observed quantitatively. The activity of SDH and M-ATPase as well as the content of muscular glycogen in model groups were found significantly lower than those of the normal groups (p < 0.01), and in this decrease Xiaopiling Granules had markedly played a preventive and therapeutic role.

Diffraction properties of a reflection photorefractive hologram

Diffraction properties of a photorefractive hologram have been described previously in most cases with Kogelnik's uncoupled-recording-wave-theory, which was originally derived for nonphotorefractive holograms. Despite its simplicity and good approximation, the theory has shown its practical limitations and discrepancies when the refractive-index perturbation is large. We study the diffraction properties of a reflection photorefractive hologram using a coupled-recording-wave approach. A closed-form expression for the diffraction efficiency is obtained. The important aspect of the new formula is that it predicts a lower cross-talk noise (or, a higher wavelength sensitivity) than Kogelnik's formula. This offers an explanation for the apodization phenomenon (i.e., lower cross-talk noise from the experiment as compared with the analytical result) as found by Rakuljic et al. [Opt. Lett. 17, 1471-1473 (1992)].

Effects of recording-erasure dynamics of storage capacity of a wavelength-multiplexed reflection-type photorefractive hologram

We investigate the effects of the recording-erasure dynamics on the storage capacity of a wavelengthmultiplexed reflection-type photorefractive hologram by using a coupled-recording-wave approach. A closed-form expression for the diffraction efficiency for on-Bragg incidence is derived. The dependence of the equalized diffraction efficiency on the number of recordable holograms is analyzed. The result shows that the storage capacity of a reflection-type hologram is of the same order of a transmission-type hologram but higher than the previous predictions based on an uncoupled-recording-wave theory.

A new functional classification of stomach cancer and its pathobiological and clinical significance

The functional differentiations of stomach cancer specimens from 121 patients were investigated by enzyme-, mucin-, affinity- and immunohistochemical methods, and the stomach cancers were divided into five functionally differentiated types: 1) Absorptive Function Differentiation Type (AFDT), 19.8%; 2) Mucin Secreting Function Differentiation Type (MSFDT), 24.0%; 3) Absorptive and Mucin-Producing Function Differentiation Type (AMPFDT), 47.1%; 4) Special Function Differentiation Type (SFDT), 0.8%; and 5) Non-Function Differentiation Type (NFDT), 8.3%. The results indicate that stomach cancer tissues of the same histological type often display differing functional differentiation, and these functionally differentiated types have different invasive and metastatic characteristics. In addition, the functionally differentiated types have particular organic affinities of metastasis and different clinical prognoses. This study suggests that this new functional classification may supplement histological classification. The mechanisms of liver and ovary metastases of stomach cancer are also discussed.

Effects of lead on root growth, cell division, and nucleolus of Allium cepa

The effects of different concentrations of lead nitrate on root growth, cell division, chromosome morphology and nucleolus in root tip cells of Allium cepa were studied. The concentrations of lead nitrate (Pb(NO(3))(2)) were 10(-7), 10(-6), 10(-5), 10(-4), 10(-3) and 10(-2) m. It was observed that lead reduces root growth and causes mitotic irregularities, including c-mitosis, anaphase bridges, and chromosome stickiness. Also, interphase cells with micronuclei, irregularly shaped nuclei and nuclei with decomposed nuclear material were noticed. The c-mitotic effect reached its maximum in the meristem at above 10(-4) m Pb, when practically almost all the anomalous dividing cells are of this type. After treatment with Pb, there were many similar silver-stained particulate materials scattered in the nucleus in short, rounded meristem cells and in long, oblong root cap cells.

Iron-thiolate induced oxidation of methionine to methionine sulfoxide in small model peptides. Intramolecular catalysis by histidine

Peptides containing either glycine and methionine, or glycine, methionine and histidine at various locations were oxidized by the dithiothreitol/ferric chloride system in phosphate buffer. The yields of peptide degradation and sulfoxide formation were measured as a function of peptide sequence and pH. In general little change of the final yields of peptide degradation is observed whereas the final yields of sulfoxide formation progressively decrease on going from pH 6.0 to 8.0. The pH profiles vary with the structure of the respective peptide. Efficient sulfoxide formation occurred when histidine and methionine were present within the same peptides sequence, and particularly when methionine was located at the C-terminus of the peptide. Added superoxide dismutase, catalase, and methanol did neither promote nor inhibit both the degradation of peptide and the formation of sulfoxide excluding free superoxide, hydrogen peroxide, and hydroxyl radicals as responsible reactive oxygen species. The observations are rationalized by invoking a pH-dependent conversion of an efficiently sulfoxide yielding oxidant into another oxidant which still degrades peptides but does not form methionine sulfoxide. The first might be a metal-bound peroxide or peroxyl species which converts into a metal-bound or 'complexed' hydroxyl radical.

Cross-talk noise in a wavelength-multiplexed reflection-type photorefractive fiber hologram

We have analyzed the cross-talk noise as affected by the wavelength spread that is due to the spectral width of the light source in a wavelength-multiplexed reflection-type photorefractive fiber hologram. The spectral bandwidth of each multiplexed channel limited by the cross-talk noise is discussed. The signal-to-noise (cross-talk) ratio is analyzed, whereby we have shown that this ratio is sensitive to the separation between adjacent multiplexed channels and to the spectral width of the light source. The cross-talk-limited storage capacity for practical photorefractive fibers is evaluated.

Upconversion-pumped blue laser in Tm:YAG

We have demonstrated an upconversion-pumped blue laser on the (1)G(4)-(3)H(6) band of Tm:YAG at cryogenic temperatures. Measurements were also made to assess the possibility of room-temperature upconversion-pumped lasers in Tm:YAG on both the (1)G(4) -(3)H(6) and the (1)D(2)-(3)F(4) bands.

Evidence from the anti-idiotypic network that the acetylcholine receptor is a rabies virus receptor

We have developed idiotype-anti-idiotype monoclonal antibodies that provide evidence for rabies virus binding to the acetylcholine receptor (AChR). Hybridoma cell lines 7.12 and 7.25 resulted after fusion of NS-1 myeloma cells with spleen cells from a BALB/c mouse immunized with rabies virus strain CVS. Antibody 7.12 reacted with viral glycoprotein and neutralized virus infectivity in vivo. It also neutralized infectivity in vitro when PC12 cells, which express neuronal AChR, but not CER cells or neuroblastoma cells (clone N18), which have no AChR, were used. Antibody 7.25 reacted with nucleocapsid protein. Anti-idiotypic monoclonal antibody B9 was produced from fusion of NS-1 cells with spleen cells from a mouse immunized with 7.12 Fab. In an enzyme-linked immunosorbent assay and immunoprecipitation, B9 reacted with 7.12, polyclonal rabies virus immune dog serum, and purified AChR. The binding of B9 to 7.12 and immune dog serum was inhibited by AChR. B9 also inhibited the binding of 7.12 to rabies virus both in vitro and in vivo. Indirect immunofluorescence revealed that B9 reacted at neuromuscular junctions of mouse tissue. B9 also reacted in indirect immunofluorescence with distinct neurons in mouse and monkey brain tissue as well as with PC12 cells. B9 staining of neuronal elements in brain tissue of rabies virus-infected mice was greatly reduced. Rabies virus inhibited the binding of B9 to PC12 cells. Mice immunized with B9 developed low-titer rabies virus-neutralizing antibody. These mice were protected from lethal intramuscular rabies virus challenge. In contrast, anti-idiotypic antibody raised against nucleocapsid antibody 7.25 did not react with AChR.

High resistance to cucumber mosaic virus conferred by satellite RNA and coat protein in transgenic commercial tobacco cultivar G-140

A chimeric vector was constructed to express cucumber mosaic virus (CMV) satellite (Sat) RNA and coat protein (CP). Transgenic lines of tobacco cultivar G-140 expressing CP and Sat-RNA were obtained; these lines had high resistance to CMV. Fifty to 70% of the transgenic plants were symptomless 90 days after inoculation with 25-50 micrograms/ml of CMV. Resistance was about twice that conferred by the Sat-RNA or the CP gene alone in transformed plants.