Biomedical subjects

Q He

Publications and source records attributed to Q He.

277 records · Page 16Linked to original sources

PubMedDate not supplied

Body mass index is different in normal Chinese and Caucasian infants.

Body mass index (BMI) is one of the anthropometric measurements for assessing nutritional status, body composition and adiposity in children. Racial differences in BMI between black and white children and adolescents have been shown in several studies. The aim of this study was to determine whether an ethnic difference in BMI exists between Chinese and Caucasian children in the first two years of life. The BMI of Chinese and Caucasian infants was compared so as to assess the usefulness of the National Center for Health Statistics (NCHS) growth reference data in the assessment of nutritional status of Chinese children. Mean weight, length and BMI were compared between six cohorts of Chinese children and five cohorts of Caucasian children together with the NCHS growth reference data. The changes in the mean BMI curves during the first two years of life in the two ethnic groups were entirely different but the different cohorts in the same ethnic groups displayed a similar pattern of change with age. The difference in change in BMI in the Chinese cohorts was related to the difference in change in their mean weight as compared to the NCHS weight-for-age reference data. In contrast, the change in mean length of the well-nourished Hong Kong Chinese children in the present study followed the mean NCHS height-for-age values. The results of this study suggest that linear growth would be better for the assessment of health and nutrition in infancy and early childhood. If BMI and weight-for-height standards were to be used then an ethnic group-specific and population based reference data set should be used.

Aging↗

PubMedDate not supplied

Benn Index at birth is associated with postnatal linear growth.

While previous research has suggested that body thinness is related to subsequent linear growth in children, it is unclear whether thinness at birth is related to linear growth in newborns and catch-up growth in small-forgestational age newborns. Drawing on data from a longitudinal growth study of 3,650 full-term Swedish babies, this study examines linear growth from birth to 6 months of age in three groups of newborns with short (< -2 SDS), appropriate (-2 to 2 SDS) and long (> 2 SDS) body length for gestational age. Among infants short at birth, the Benn Index (kg/m2.69) at birth was not related to the odds of short stature (< -2 SDS) at age 6 months (odds ratio = 1.03; p > 0.10). Nonetheless, the Benn Index was positively related to growth velocity in the first 6 months of life in the short (p = 0.060), appropriate (p < 0.05), and tall (p < 0.05) for gestational age newborns. Use of the Ponderal Index (kg/m3) would give similar results. The findings suggest that nutritional status at birth is related to linear growth velocity in newborns.

Birth Weight↗

PubMedDate not supplied

Effects of adriamycin and hyperthermia on cellular uptake of [3H]thymidine and its significance for the incorporation into DNA.

Inhibition of the salvage DNA synthesis was studied in ascites tumour cells up to 240 min at moderately increased temperatures of 39 degrees C, 40.5 degrees C and 43 degrees C alone or in combination with adriamycin (ADR). Hyperthermia and ADR acted additively on salvage DNA synthesis. The [3H]thymidine (TdR) incorporation was strongly related to the cellular uptake of [3H]TdR. In order to evaluate the significance of the decrease in [3H]TdR uptake for the incorporation into DNA, the thymidine kinase (TK) has also been studied. TK activity started to decrease at a temperature of 39 degrees C, probably due to inhibition of translation and/or transcription of the enzyme, and was almost completely inhibited at 43 degrees C. ADR did not affect TK activity. Inhibition of DNA synthesis by aphidicolin neither decreased the ability of the cell to take up [3H]TdR nor the ability to affect TK activity. We concluded that moderate increases in temperature alone, or in combination with ADR, inhibit salvage DNA synthesis by inhibition of TdR uptake, possibly due to inhibition of phosphorylation; ADR, on the contrary, inhibits TdR uptake by other mechanisms such as changes in membrane function.

Animals↗

PubMedDate not supplied

Effect of hyperthermia on thymidine salvage as related to DNA synthesis.

The effect of increasing temperature up to 43 degrees C on thymidine (TdR) salvage, i.e. uptake of TdR, thymidine kinase (TK) activity, intracellular amount of thymidinetriphosphate (dTTP) and specific activity of 3H-dTTP and incorporation of dTTP into DNA, was studied in ascites tumour cells in vitro. While the uptake of [3H]TdR was almost unchanged up to 40.5 degrees C and 2.4 h followed by a decrease at later times and higher temperatures, TK activity declined already after 30 min in a temperature-dependent way, leading to a decrease in cellular amount of dTTP reaching almost undetectable values at 43 degrees C and 6.0 h. The specific activity of [3H]dTTP in the cell was elevated at 39 degrees C and 43 degrees C, but somewhat reduced at 40.5 degrees C. Incorporation into DNA of [3H]TdR decreased in a temperature-dependent way with increasing incubation time. After correction for specific activity of [3H]dTTP, however, the incorporation of [3H]TdR into DNA at 39 degrees C and 40.5 degrees C was unchanged up to 2.4 h and for 40.5 degrees C up to 6.0 h, while incorporation into DNA at 43 degrees C was still reduced. The overall protein synthesis was also reduced in a temperature-dependent way. We concluded that phosphorylation of TdR to dTMP was more sensitive to moderately elevated temperatures than uptake of TdR and DNA synthesis per se, caused by a reduced TK activity. The decline in TK activity was probably due to a decrease in TK polypeptide synthesis.

Animals↗

PubMedDate not supplied

Rapid identification of Bordetella pertussis pertactin gene variants using LightCycler real-time polymerase chain reaction combined with melting curve analysis and gel electrophoresis.

Recently, eight allelic variants of the pertactin gene (prn1-8) have been characterized in Bordetella pertussis strains isolated in Europe and the United States. It has been suggested that the divergence of the pertactin types of clinical isolates from those of the B. pertussis vaccine strains is a result of vaccine-driven evolution. Sequencing of the prn, which is relatively time-consuming, has so far been the only method for the differentiation of prn types. We have developed a rapid real-time polymerase chain reaction assay suitable for large-scale screening of the prn type of the circulating strains. This method correctly identified the prn type of all tested 41 clinical isolates and two Finnish vaccine strains. The method is simple and reliable and provides an alternative for sequencing in pertussis research.

Amino Acid Sequence↗

PubMedDate not supplied

A new cell proliferating marker: cytosolic thymidine kinase as compared to proliferating cell nuclear antigen in patients with colorectal carcinoma.

BACKGROUND: Proliferation markers are necessary for reliable diagnosis. Here we have presented for the first time thymidine kinase 1 (TK1) as a proliferative tumor marker for colorectal carcinoma. PATIENTS AND METHODS: Expression of TK1 in 54 colorectal lesions and 20 colorectal adenoma lesions was detected by immunohistochemistry technique (ABC). Proliferating Cell Nuclear Antigen (PCNA) was run in parallel. RESULTS: TK1-Labelling Index (LI) (65%) was higher than PCNA-LI (52%) in the malignant lesions, although not significantly different (p = 0.1717) between them. TK1-LI as well as PCNA-LI showed significant differences between colorectal carcinoma and colorectal adenoma (TK1 p = 0.0005, PCNA p = 0.0005). Both TK1-LI and PCNA were significantly different in respect to tumor stages (TK1 p = 0.0002, PCNA p = 0.0284). However, only TK1-LI showed significant difference in respect to tumor grades (p = 0.014), but not PCNA-LI (p = 0.132). CONCLUSION: TK1-LI showed more potential as a proliferating marker in colorectal carcinoma than PCNA-LI, especially for evaluating high-risk tumor grade and advanced stage in colorectal carcinoma.

Adenocarcinoma, Papillary↗

PubMedDate not supplied

Improved measurement of tyrosine-phosphorylated DNA-PKcs by isoelectric focusing as an indirect determination of DNA-PK activity in vivo.

UNLABELLED: Isolation of various phosphorylated forms of DNA-PKcs by SDS gel electrophoresis is difficult because of the same molecular weight. By isoelectric focusing (IEF), we confirmed a de-phosphorylated (pI 9.0) and a phosphorylated (pI 6.9) form of DNA-PKcs. When cells were damaged by X-irradiation (5 Gy), an additional tyrosine-phosphorylated (p-Tyr) DNA-PKcs form (pI 6.3) appeared in both nuclear and cytoplasmic fractions, after 30 minsutes. CONCLUSION: IEF in combination with Western blotting of p-Tyr-DNA-PKcs results in an appropriate separation of the p-Tyr form from other phosphorylated forms of DNA-PKcs, which may permit an indirect measurement of changes in DNA-PK activity in irradiated cells.

Animals↗