[An epidemiological investigation of an outbreak of Legionnaires' disease in a college in Tang Shan]

An outbreak of Legionnaires' Disease (LD) in a college in Tang Shan in the winter of 1987 was reported. Indirect fluorescent assay (IFA) for the antibodies against Legionella Pneumophila (Lp) serogroups I, VI and VIII was carried out in 52 students and 6 teachers. It was found that the antibody titer of LP VI greater than or equal to 1:256 was in 12 students. The clinical figures of these patients were classified into three types: pneumonia 3, fever 9 and asymptomatic 1. It was postulated that the outbreak was associated with water contamination of the college bathroom. There were more patients in two dormitories than in the others, which was suggested that the possibility of a spread of the disease from a person to the others.

[A study on the dental adhesive containing phosphate diesters]

Although a lot of kinds of dental adhesives have been applied recently, all of them cannot meet clinical requirement completely. This paper reports a new dental adhesive containing partial phosphate diesters developed by us. We synthesized aryl phosphorodichloridates (APDC), nine kinds of phosphate diester (PDE) adhesive monomers, sodium p-toluenesulfinate (TSS) and p-toluenesulfinic acid (TSA) accelerators, polymethyl methacrylate (PMMA) powder and the other compounds. The chemical structures of PDE adhesive monomers were confirmed by IR, 1HNMR, 31PNMR, refractive index and elementary analysis etc. The results showed that the tensile bond strength (TBS) between PDE dental adhesive and human tooth was better than others reported in China and some others reported in literature.

[Studies on immunoregulation and hypersensitivity of secretary otitis media]

Sixty patients with secretary otitis media (SOM) and 50 control cases were studied for their cellular immunity and hypersensitivity. Most of patients revealed that total T or T cell subpopulations were below those of the control. Eighty percent of patients had high serum IgE level and 81.2% as Positive in intradermal skin tests on inhalant allergy, but only 51.7% of patients had clinical symptoms of allergy. It was found immunologically that SOM occurred more frequently in allergic patients and most of them had abnormality of immunoregulation, and that there was a subclinical allergy for some of the patients. Allergy might play a significant role in the etiology of this disease. Authors suggest that it is necessary for patients with SOM to have some tests and treatment of immunology.

[Morphological observation of effect of bee pollen on intercellura lipofuscin in NIH mice]

By histochemical method we have observed the effect of bee pollen on lipofuscin in NIH mice. The results show that oral administration of bee pollen at 10 g/kg/d markedly reduces lipofuscin in cardiac muscle in aged mice, significantly inhibits the increase of lipofuscin in cardiac muscle, liver, brain and adrenal gland cells induced by orally given peroxidized corn oil or iv alloxan. This action may be related with the anti-ageing effect of bee pollen.

[Various methods for purification of urine Tamm-Horsfall protein]

The measurements of serum, urine Tamm-Horsfall protein (THP) and its antibody are essential to the early diagnosis of tubulointerstitial diseases and acute rejection after renal transplantation. The purification of THP proves to be the key procedure for the production of diagnostic kit. Once, twice and three times salt precipitation with 0.58 mol/L NaCl and chromatography with Sephadax G-200 were adopted to purify urine THP. Enzyme immunoassay was used to detect the antigenicity of the products, SDS-PAGE to determine the molecular weight (MW) and the electrophoretic purity (EP), Beckman DU-7 model spectrophotometer to scan the ultraviolet absorption spectrum. Evaluation of the four methods was based on the purity and the antigenicity of the produced THP, the output, the complexity of procedure, and the cost of required materials. Results show that the MW of THP is 93.0 kd; the ultraviolet absorption maximum is at lambda = 278 nm; the outputs are 7.5, 5.5, 3.8, and 0.4 mg/L; the concentrations of THP with antigenicity are 65%, 75%, 98% and 100%, respectively, and the EPs of three times salt precipitation and chromatography are better. It is concluded that three times salt precipitation should be recommended because of its excellence in purity and antigenicity of the produced THP, the simplicity of manipulation, and the cheapness of the materials needed.

[Variation of cAMP in cerebral cortex and hippocampus in seizure mice induced by coriaria lactone]

To study the relationship between cAMP and epilepsy, we investigated the effects of coriaria lactone (CL) on the levels of cAMP in cerebral cortex and hippocampus. Fifty normal WC1 mice were divided into 5 groups. All groups were injected with CL (2.5 mg/kg, i.m.), except the control group which was injected with NS. The concentrations of cAMP were measured after the animals had been immersed in liquid nitrogen to die at different phases of seizure development induced by CL (before seizures, in mild seizures, during severe seizures, and after severe seizures). The results indicated that the levels of cAMP in both cerebral cortex and hippocampus were significantly increased (1.73-fold and 1.33-fold) in severe seizure, and they continuously increased (1.85-fold and 1.45-fold) after severe seizures. On the other hand, no changes of cAMP were observed in mild seizures and before seizures. These data suggested that accumulation of cAMP is probably the result of seizure activity rather than the cause of seizure.

High efficiency transient expression of eukaryotic genes: use of an HSV-1 immediate early promoter (ICP4)

We have compared the transcriptional efficiencies of a number of eukaryotic promoters following DNA-mediated transfection into cultured rat hepatoma cells. We find that the highest levels of expression for the bacterial chloramphenicol acetyltransferase (CAT) reporter gene are observed with a herpes simplex virus type 1 (HSV-1) immediate early promoter when co-transfected with an expression construct bearing the gene for the HSV-1 transcriptional activator protein VP16. This transactivation phenomenon is specific for the HSV-1 immediate early promoter and increases the expression of the reporter gene 7-fold. Expression from the ICP4 promoter is 2.5-fold greater than the other promoters tested. In addition, expression from the ICP4 promoter can be induced, at varying times following transfection, by infecting the cells with HSV-1 viral particles. Two plasmids have been constructed which contain the HSV-1 ICP4 promoter adjacent to a multiple cloning site. One of the plasmids also contains SV40 splicing and polyadenylation signals.

[Specific monoclonal antibodies to F41 adhesin of enterotoxigenic Escherichia coli and their potential uses as diagnostic and therapeutic reagents]

A set of hybridoma cell lines, namely, L10, B10, C32, B1, E7, E40 and B49, secreting monoclonal antibodies (MABs) specific to F41 adhesin antigens of ETEC was obtained by somatic hybridization. These MABs manifested strongly specific binding reactivities in DA, ELISA and IFA to all tested F41+ ETEC strains. All these MABs recognized the same or closely related epitopes on the adhesin, as indicated in antigen-competition ELISA with HRP-labeled MABs. The distribution patterns of these epitopes which appeared repeatedly on each pilus were visualized by MAB-immunogold technique and immunoelectron microscopy. The adhesion of ETEC bearing F41 adhesin to the epithelial cells of small intestine from new borne calves and piglets was inhibited in vitro by F41-specific MABs. A dot-immunobinding assay based on F41-specific MABs was developed for determining F41 antigens in fecal samples with HRP-labeled MABs. The assay was highly sensitive and specific, and could be used in rapid detection and screening of F41 adhesin antigens in field samples.

[Study on change in zinc concentration for diabetic cataractous lenses in rats by means of XIXA]

The SD rats were injected with streptozotocin to induce diabetic cataract. Element Zn as well as K, Ca, Mn, Fe, Cu, Pb, Se, etc. in the eye lenses was determined by means of X-ray induced X-fluorescence analysis (XIXA). Compared to values for normal healthy rats, the concentration of Zn and Fe in the cataractous lenses increased, the concentration of K decreased, and that of the others did not change prominently. The change in Zn concentration was probably to meet the needs of the metabolic adjustment in the eye lenses, which would not be the reason for directly inducing diabetic cataract.

[Detection of sorbitol content in crystalline lens of normal rats and rats with diabetic cataract by 1H-NMR]

The pulse Fourier NMR was employed to measure the artificial diabetic cataract lens at various stages of its formation, and the lenses of the normal rats. Data obtained by using this method show that all the peaks that of water concentrate in the range of delta less than 4 ppm. The peak value at delta = 3.20 ppm is on a marked increase during the formation of cataract which is caused by the phosphate metabolites, such as GPC, ATP, ... etc, in cataract lens. With the development of the disease, the peak width at delta = 3.73 ppm becomes greater and greater, which shows that the activity of sorbitol dehydrogenase has decreased. This leads to a high concentration of the sorbitol in the cataract lens. Consequently, the osmosis pressure in the cataract lens is increased, and excessive water might dip into the crystalline lens to keep the balance of the osmosis pressure. And this might result in the hydration of the fiber cell of the crystalline lens, which might cause a swelling or blisters. These results are in favour of the prolongation of the relaxation time of cataractous lens reported in our other papers, and also support those gained by biochemical studies issued in the medical literature.

TCM treatment of retinal vein occlusion in 216 cases

Traditional Chinese Medicine was adopted in the treatment of 216 cases (219 eyes) of retinal vein occlusion. The period of treatment averaged 3 months; the total rate of efficacy was 80.4%. During an average follow-up of 3 years, 84.1% of the patients maintained a stable or slightly improved vision. The authors believed that treatment of the disease with TCM promoted the absorption of blood and formation of collateral circulation, and suppressed neovascularization, thus preventing repeated bleeding that would lead to serious complications.

[Effects of bee pollen on lipid peroxides and immune response in aging and malnourished mice]

The results showed that the level of hemolysin (HC), the numbers of plaque forming cells (PFC) and specific rosette forming cells (SRFC) in primary response to sheep red blood cells (SRBC) were markedly lowered and the lipoperoxide level in brain, liver and serum was increased in aging (over 18 months) and malnourished mice fed with ground corn in comparison to normal controls, while HC and the numbers of PFC and SRFC were significantly increased and the lipoperoxide level was markedly decreased after treatment with bee pollen 10 g/kg/d orally for 3 months and with 20% bee pollen-containing ground corn for 3 weeks respectively. The reduction of total protein and albumin contents of serum, DNA, RNA and protein contents of spleen and thymus in mice fed with ground corn can be prevented by adding 20% bee pollen in ground corn diet.

[Study on the metabolic changes of hormones regulating water and electrolytes before and after acute water loading in myxedematous patients]

The average plasma AVP in 12 cases of patients with overt myxedema was higher than that of normal controls (n = 5) before water loading, though there was no significant difference (P greater than 0.05). The plasma ANP levels were increased (P less than 0.05). After water loading the average plasma osmolality level of patients was lower, and the mean plasma AVP concentration of patients was not suppressed after loading. A disturbance in water clearance was demonstrated. The mean levels of plasma ANP and aldosterone were not markedly changed in patients before and after loading. These observations coincide with the changes of SIADH. Most of the above blood parameters were improved along with thyroid function in 9 patients who were restored to normal after replacement with desiccated thyroid.

[Affective disturbances in patients with breast cancer]

40 cases of breast tumor (cancer group 20 cases, benign tumor group 20 cases) hospitalized from October, 1986 to April, 1987 were investigated by interview, HAMD, SCL-90 and so on. Results showed that 10 cases met diagnostic criteria of organic affective syndrome defined by DSM-III. The morbidity of depression among all cases was 25 per cent, but the morbidity of depression in breast cancer group was higher than in benign tumor group. Causes of depression in breast cancer were analysed. Authors consider that causes of depression are not relating to operation on breast, but probably relating to biological and psychosocial factors.

General formulation for the integrated effective emissivity of any axisymmetric diffuse blackbody cavity

A general method for the precise evaluation of the integrated effective emissivity of a diffuse frustrum-cone cavity is formulated. The mathematical expressions derived can be applied to calculate precisely the integrated emissivity of, or the irradiance of a detector from, any practical axisymmetric cavity with circular symmetry. Some typical values of integrated emissivity are presented for cylinders, cylindro-cones, double cones, and cylindro-inner-cones, and comparisons between such cavities are made.