Developmental control elements in the promoter of a Drosophila vitelline membrane gene

DNA fragments from the 5' flanking region of Drosophila melanogaster vitelline membrane gene VM26A1 were fused to hsp/lacZ reporter genes, reintroduced via P-element-mediated germ line transformation, and functionally assayed by histological staining for beta-galactosidase activity. A developmental control element capable of promoting the basic vitelline membrane (VM) expression pattern was found within a 176-bp region. Additional multiple genetic control elements were found to be involved in modifying the level and spatial pattern of reporter gene expression but these required the 176-bp element in order to function. Unexpectedly, in isolation this 176-bp core element also promotes abnormal expression of the reporter gene in border cells of stage 8 and 9 egg chambers. This abnormal border cell expression is apparently suppressed in the native gene by an adjacent negative control element.

Health behavior and outcomes in sequential pregnancies of black and white adolescents

OBJECTIVE

To examine the relationships among parity, preterm delivery, fetal growth retardation, and prenatal care utilization in first and second adolescent pregnancies.

DESIGN

A longitudinal, retrospective study in which obstetric, behavioral, and sociodemographic data were used to examine birth outcomes of 737 low-income black (80%) and white (20%) teenagers delivering first and second singleton infants at 20 or more weeks' gestation.

SETTING

Public health clinics in Jefferson County, Alabama, between January 1983 and February 1990.

MAIN OUTCOME MEASURES

Mean birth weight, preterm delivery, fetal growth retardation, Apgar scores, and perinatal mortality.

MAIN RESULTS

In their second pregnancies, adolescents presented 2.8 weeks later for care (P = .0001) and made fewer total clinic visits. Mean infant birth weight increased by 91 g (P = .0005). This increase was significantly associated with an increase in maternal prepregnancy body mass index. The rate of fetal growth retardation decreased (P = .0001) and the rate of preterm delivery increased (P < .02) in the second pregnancy. The rate of recurrence of fetal growth retardation was 13% and the rate of preterm delivery was 46%.

CONCLUSIONS

Poorer utilization of prenatal care and high risk for recurrence of adverse outcomes are characteristic of adolescents' second pregnancies and should be considered in teenage pregnancy intervention programs.

Separation of N-acetylglucosamine and N-acetylmannosamine by chromatography on Sephadex in borate buffer

Several procedures have been used previously for the separation of N-acetylglucosamine and N-acetylmannosamine, which are based on the difference in strength of the borate complexes of the two N-acetylhexosamines and include paper chromatography on borate-treated paper, paper electrophoresis in borate buffer, and anion-exchange chromatography of the borate complexes. In the present study, we have observed that the two sugars, despite their identical size in noncomplexed form, may also be separated by gel chromatography in borate buffer. Nearly complete resolution was obtained by chromatography on a column (1.5 x 117 cm) of Sephadex G-15, which was eluted at room temperature with 0.27 M sodium borate, pH 7.8 (prepared from H3BO3 by addition of NaOH), at a flow rate of 10 ml/h. This procedure complements existing methods for the separation of N-acetylmannosamine and N-acetylglucosamine and has the advantage that it can be carried out on a relatively large preparative scale.

[Studies on CD spectra of derivatives of shikonin and alkannin]

The circular dichroism (CD) and electronic absorption spectra of seven derivatives of shikonin and alkannin isolated from the roots of Onosma confertum W.W. Smith (from Sichuan) and Arnebia euchroma (Royle) Johust (from Xinjiang) were described. Each pair of CD spectra obtained was exact mirror images and the UV spectra of these compounds were very similar. In comparison with the CD spectra of shikonin given in literature, the configuration of the pigments from Sichuan was assigned R and from Xinjiang were all S.

[The effect of 211At labelled monoclonal antibody against gastric cancer on DNA, RNA and protein synthesis in gastric cancer cell]

By means of nuclide precursor incorporation, the effects of 211At labelled monoclonal antibody against gastric cancer (211At-3H11McAb) on DNA, RNA and protein synthesis in gastric cancer cell were studied. The results show that 211At-3H11McAb and Na211At-3 inhibit 3H-TdR, 3H-UR and 3H-Leu incorporation, especially 3H-UR incorporation, into gastric cancer cell at 3.7 x 10(4)Bq and 1.85 x 10(5)Bq; the inhibiting rates depend on concentration. The DNA biosynthesis in gastric cancer cell gradually recover after the drug is removed, suggesting that the drug should exert an inhibiting action on DNA biosynthesis in tumor cell through interference of DNA metabolism.

Light-dependent delay in the falling phase of the retinal rod photoresponse

Using suction electrodes, photocurrent responses to 100-ms saturating flashes were recorded from isolated retinal rods of the larval-stage tiger salamander (Ambystoma tigrinum). The delay period (Tc) that preceded recovery of the dark current by a criterion amount (3 pA) was analyzed in relation to the flash intensity (If), and to the corresponding fractional bleach (R*0/Rtot) of the visual pigment; R*0/Rtot was compared with R*s/Rtot, the fractional bleach at which the peak level of activated transducin approaches saturation. Over an approximately 8 ln unit range of I(f) that included the predicted value of R*s/Rtot, Tc increased linearly with ln I(f). Within the linear range, the slope of the function yielded an apparent exponential time constant (tau c) of 1.7 +/- 0.2 s (mean +/- S.D.). Background light reduced the value of Tc measured at a given flash intensity but preserved a range over which Tc increased linearly with ln I(f); the linear-range slope was similar to that measured in the absence of background light. The intensity dependence of Tc resembles that of a delay (Td) seen in light-scattering experiments on bovine retinas, which describes the period of essentially complete activation of transducin following a bright flash; the slope of the function relating Td and ln flash intensity is thought to reflect the lifetime of photoactivated visual pigment (R*) (Pepperberg et al., 1988; Kahlert et al., 1990). The present data suggest that the electrophysiological delay has a similar basis in the deactivation kinetics of R*, and that tau c represents TR*, the lifetime of R* in the phototransduction process. The results furthermore suggest a preservation of the "dark-adapted" value of TR* within the investigated range of background intensity.

New posture equilibrometer for the diagnosis of vestibular disease

The vestibulospinal level of vestibular function is commonly neglected in the evaluation of vertiginous patients. We have now developed a new posture equilibrometer. A transducer is placed on the head of the subject being tested. With this meter we can record body swaying, X (left-right) and Y (fore-aft) components of angular displacement, angular velocity, and angular acceleration. A detailed analysis of the data can be made by having patients keep their eyes either open or closed during the Romberg test. The head is turned left or right in this test, while the eyes are opened and closed in the Mann test. The posture equilibrometer has enabled us to evaluate more precisely vestibulospinal function and sensory interactions.

A posture equilibrometer for the diagnosis of vestibular disease

Since the vestibulospinal level of vestibular function is frequently neglected in the evaluation of vertiginous patients, we developed a new posture equilibrometer for recording body swaying X (left-right) and Y (fore-aft) components of angular displacement, velocity, and acceleration with its transducer on the head of the subject. The data from patients undergoing Romberg test with eyes open and closed, Romberg test with head turned left and right and Mann test were analysed. We conclude that the equilibrometry allows one to evaluate precisely the vestibulospinal function and the sensory interaction.

Effect of althesin (CT-1341) on thyroid-adrenal function in man

The effects of althesin on adrenocortical and thyroid function were investigated by measuring plasma concentrations of cortisol, thyroxine (T4) and free thyroxine index (FTI) in 29 surgical patients. Althesin did not change the plasma cortisol concentrations from the preanaesthetic control value; however, the concentrations increased significantly after the start of surgery and thereafter. Althesin anaesthesia per se decreased slightly, but significantly, plasma T4 concentration, but did not influence the FTI value. The surgical operation increased the FTI value slightly but significantly. Our data would suggest that Althesin anaesthesia can be used in patients who have abnormal adrenocortical or thyroid activity.