Maximal aerobic capacity and its relationship with physical growth in Chinese children

Maximal aerobic capacity and its relationship to physical growth in 463 Chinese children and adolescents aged 10-19 is reported. Results show that VO2max, VO2max/height and VO2max/HRmax positively relate to measures of physical growth such as height, weight and lean body mass (LBM). Correlation of VO2max/weight with physical growth variables is high and positive in boys and low and negative in girls. The sample is divided to two groups on each variable: well-developed and relatively poorly-developed according to height, weight and LBM. SDS values of VO2max, VO2max/height and VO2max/HRmax are higher in the first group than in the second group. In contrast, SDS values of VO2max/weight and VO2max/LBM are greater in second group. The similarity of results between SDS values with correlation analysis suggest that weight and LBM are probably the decisive factors that influence VO2max.

[Experimental studies of jiantang oral solution on reducing glycemia]

Mice or rats were pretreated P. O. with 8.0 gg.kg-1, 15.0 g.kg-1 and 30.03 g.kg-1 of Jiangtang Oral Solution once daily for 10 days respectively. The results showed that Jiangtang Oral Solution did not affect the glycemia and lipid in normal mice and rats, but significantly lowered the blood sugar in hyperglycemic mice and rats induced by alloxan, adrenalin, and streptozotocin. Meanwhile, Jiangtang Oral Solution significantly lowered blood lipid in mice and rats induced by yolk and high cholesterol foods. This study provides a reliable pharmacologic base for the clincal use of Jiangtang Oral Solution.

Abnormal change of p53 gene in gastric and precancerous lesions and APC gene deletion in gastric carcinoma and near tissues

p53 gene mutation (exon4, 5, 6, 7, 8 and intron6) in gastric cancer and precancerous lesions and p53 gene (exon4 and ontron6), APC gene deletion in gastric carcinomas were studied by PCR/SSCP and PCR/RFLP. Results showed mutation rate of p53 in metaplasia, dysplasia and gastric carcinoma was 37.5% (3/8), 42.17% (8/19), 53.33 (16/30) respectively. There was significant difference among groups of metaplasia, dysplasia, cancer and normal controls. No exon8 mutation was found in metaplasia and dysplasia, but 4 cases were found to have exon8 mutation in cancer group. It is suggested that exon8 mutation occurs at the late stage of gastric cancer, but exon 5, 6, 7 mutation occur in the course of precancerous lesion to cancer. Loss of heterozygosity (LOH) of exon4, intron6, APC was 47, 37% (9/19), 8.73% (2/23), 16.67% (3/18) respectively. LOH of exon4 had something to do with poor differentiation, lymph node metastasis, depth of invasion. LOH of exon4 may be of prognostic marker of gastric cancer. We are led to conclude that p53 gene mutation is an early event and perhaps work together with ras oncogene in gastric carcinogenesis.

Complexometric determination of metal ions by microscopic diffusional titration

Acid/base titrations of pico- and femtoliter microsamples have been performed previously using a diffusional microburet (DMB) for reagent delivery in a simple droplet-heptane system (Gratzl, M.; Yi, C. Anal. Chem. 1993, 65, 2085-2088). The lowest delivery rate achieved with a DMB was about 6 fmol/s, which would correspond to about a 1 microL/year volumetric flow rate with a hypothetical equivalent mechanical delivery scheme (Yi, C.; Gratzl, M. Anal. Chem. 1994, 66, 1976-1982). In this work, the feasibility of complexometric titrations in microscopic samples is explored. Stability of pH in the microdroplets required for different determinations and the effects of DMB shank geometry on titration characteristics are also studied. Diffusional microtitrations of Fe(III), Zn(II), and Cu(II) have been performed with EDTA. Xylenol orange and Eriochrome Black T provide clear color changes at the end point of the respective titrations, despite the microscopic size of the samples (between 16 and 1570 pL, corresponding to diameters between 30 and 144 microns). Random errors of the determinations relative to full scale were 6.6% for Fe(III), 5.8% for Cu(II), and 7.9% for Zn(II). The pH required for EDTA titrations of the individual metal ions stays stable in the acidic range. This makes the microscopic titration of a number of metal ions, such as Fe(III), Fe(II), Cu(II), and Pb(II), feasible in a simple droplet-heptane system without any modification. With a higher density of strongly alkaline buffer droplets (about 100 droplets/mm2) sprayed on the bottom of the Petri dish, or by flushing N2 above the heptane, the microscopic samples can also be kept alkaline despite ambient CO2 present. In this way, Zn(II) can also be titrated in microdroplets, requiring a pH around 10. This work renders it possible to perform a variety of complexometric titrations and other chemical manipulations in microdroplets even if they need to be kept alkaline. Similar titrations in single biological cells to assess intracellular buffer capacities of different metal ions, such as Ca(II) and Mg(II), are underway.

[Sternocleidomastoid muscle lengthening for the cure of muscular torticollis]

A Z-plasty was designed to lengthen the sternocleidomastoid muscle for the treatment of muscular torticollis. Since September 1990, forty-nine patients (36 males, 13 females) have been treated. Their age ranged from 2 to 22 years old. Follow-up of there months to three years showed 95.9% of them were good results. The paper not only described the operative procedure, indications, choice of anaesthesia. postoperative functional exercise and the application of neck splint, but also emphasized the aesthetic effect to the operation.

Chlamydia trachomatis as a possible cofactor for Kaposi's sarcoma in AIDS

AIDS-associated Kaposi's sarcoma (KS) is much more frequent in patients acquiring HIV infection via the sexual route. Epidemiological studies have confirmed the likely involvement of a sexually acquired cofactor in the pathogenesis of this form of KS. We have formulated a set of postulates, epidemiological and experimental, to fit a single unifying hypothetical agent. Chlamydia trachomatis is one of 3 agents to fit the epidemiological criteria. Our data suggest a possible association between increased IgG serum antibody to C. trachomatis and the occurrence of KS. Conversely, higher titres of IgG serum antibody to C. pneumoniae were associated with the absence of KS. We feel that it is important to study further the relationship between C. trachomatis and KS.

Behavior of extraordinary rays in uniaxial crystals

We have experimentally investigated the behavior of extraordinary rays (E rays) in uniaxial crystals for two cases: that in which optical axes are parallel to the surfaces and that in which they are inclined. The E ray always rotates around the ordinary ray (O ray) in the same direction that the crystal rotates around its surface normal. For the case when the axes are parallel to the surface, we discovered that the E ray rotates up to α = 2π as the crystal rotates to ? = π. The E ray traces a series of ellipses as the angle of incidence is varied. Snell's law is valid for the E ray only when the optical axes are perpendicular to the plane of incidence. For the case in which the optical axes are incident, the E ray and the crystal rotate at different speeds except for the case of normal incidence. The speed of rotation increases with the incidence angle. The ray traces a curve known as the Pascal worm, which is described by the equation (x(2) + z(2) - mx)(2) = n(2)(x(2) + z(2)). When the optical axes coincide with the plane of incidence, the space between the rays in the plane is not related to the angle of incidence.

Development and characterization of a new, highly specific antibody to the human chorionic gonadotropin-beta fragment

In addition to high concentrations of hCG, pregnancy urine contains even higher concentrations of a fragment of the hCG beta-subunit. This biologically inactive material complicates immunological measurement of hCG, since it cross-reacts with many polyclonal and monoclonal antibodies to the hCG beta-subunit that are employed for assays of hCG in urine. Although we and others have developed antibodies to this fragment, specific measurement of the fragment in the presence of free hCG beta has remained difficult due to intrinsic cross-reactivity of these antibodies with the intact hCG beta. Rather than attempt to increase specificity by assay optimization, we developed a new, highly specific monoclonal antibody, designated B210, which cross-reacts less than 0.1% with the free hCG beta-subunit in both liquid and solid phase immunoassay formats. We have used this new monoclonal antibody in immunoradiometric assays to measure specifically the hCG beta fragment in urine throughout pregnancy as well as in the sera of two individuals with cancers producing the hCG beta-subunit. We discovered that the hCG beta fragment can bind three monoclonal antibodies simultaneously, indicating that although the epitope for antibody B210 is a new determinant exposed on the hCG beta fragment and not on intact hCG or on free hCG beta-subunit, the hCG beta fragment retains at least two other hCG beta-related epitopes intact, i.e. those that bind monoclonal antibodies B108 and B201.

The involvement of pineal gland and melatonin in immunity and aging. I. Thymus-mediated, immunoreconstituting and antiviral activity of thyrotropin-releasing hormone

Circadian, continued treatment with melatonin during the dark cycle produces changes in the blood level of thyroid hormones in aging mice. Thyroid-stimulating hormone (TSH) and thyrotropin-releasing hormone (TRH) antagonize the involution of the thymus produced by prednisolone. This effect of TRH does not seem thyroid dependent. TRH restores antibody production in non-responder athymic nude mice but does not exert this effect in neonatally thymectomized mice. Moreover, this activity does not correlate with thyroxine levels. TRH exerts a powerful protective effect in mice challenged with encephalomyocarditis (EMC) virus. Presumably pineal melatonin exerts its varied regulatory functions via hypothalamic TRH.