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8-Methoxypsoralen (8-MOP) when irradiated with long wavelength ultra-violet radiation (UV-A) inhibits DNA synthesis in lymphocytes in vitro and in vivo. 8-MOP binds reversibly to DNA in the dark; when exposed to UV-A, covalent monoadducts and cross-links are formed with the DNA. The present study correlates the cytotoxic effects of 8-MOP plus UV-A with DNA crosslinking. E-B virus transformed human lymphoblastoid cells were suspended in a colorless salt solution containing 8-MOP and exposed to UV-A from fluorescent lamps filtered to remove radiation below 320 nm (22.5 J/m2-sec). Cells were then returned to complete medium and assayed for survival (by daily counts of viable cells and by cloning in microtiter wells) and for DNA crosslinking by alkaline elution. 8-MOP alone or UV-A alone resulted in minimal to no alterations in survivial or in DNA crosslinking. DNA crosslinking was found to be linearly dependent on 8-MOP concentration (in the range of 0.01–1.0 μg/ml) for 3 different UV-A doses (3000–15000 J/m2). The surviving fraction declined exponentially as a function of the relative number of DNA crosslinks. These results suggest that the cytotoxic effects of photoactivated 8-MOP in human lymphoblastoid cells may depend on DNA interstrand crosslinks.

In a cross-sectional study of 210 pregnancies resulting in above-average-sized term infants, ponderal and ponderal-like indices were found to be highly correlative with fetal overgrowth. Clinical usefulness, however, is limited because for each index, most large-for-gestational age infants remain unidentified.

In a cross-sectional study of 210 pregnancies resulting in above-average-sized term infants, biparietal diameter, femur length, and abdominal circumference were found to differ among three birth weight percentile groups (greater than 90, 76 to 90, and 51 to 75). Growth rates, however, were similar. Estimated fetal weights, derived from four formulas, showed the same pattern. Differences between large for gestational age infants and other above average sized infants exist; changes in growth are likely to have occurred before the thirty-third week of gestation.

The possibility that the radiosensitivity of lymphoblastoid cell lines from patients with ataxia telangiectasia (A-T) is due to an aberrant content of histones has been examined. The histone pattern of lymphoblastoid cell lines derived from A-T patients was found to be indistinguishable from that obtained from normal individuals. X-ray irradiation led to a greater decrease in cell growth rate in the A-T cells than in the normal cells but was accompanied by a greater decrease of DNA synthesis rate in the normal cells. This difference in radiosensitivity was not reflected in differences in the content or rates of synthesis of histones or of major non-histone proteins in these cells. Reduction in the rate of DNA synthesis was not associated with the appearance of the lysine-rich histone variant H1°. We conclude that the hypersensitivity to ionizing radiation in A-T cells is not due to fundamental differences in the composition or synthesis of the major chromosomal proteins.

Fetal weight in utero was estimated sonographically within one week of delivery in 70 live-born fetuses of diabetic gravidas. The best estimates of weight were obtained with formulas dependent on biparietal diameter, abdominal circumference, and femur diaphysis length, and with formulas using the two variables of femur diaphysis length and abdominal circumference. Use of a special formula for the fetus of a diabetic mother was not of additional benefit. Acceptable weight estimates for the macrosomic diabetic fetus were not obtained.

In a study of 324 term pregnancies, fetal measurements (biparietal diameter, femur length, and abdominal diameter) obtained within one week of delivery correlated more strongly with relative birth weight than with menstrual age.

In a cross-sectional study of 87 large-for-menstrual-age term infants, intrauterine growth was found to be linear, 34 g per day. Differences between diabetic and nondiabetic pregnancies were not evident.

Among 246 term patients undergoing ultrasonic evaluation within 1 week of delivery, a grade-three placenta was found in 39.4%. Advanced placental maturity was not associated with altered fetal growth rates or an increase in small- or large-for-gestational infants. At term, advanced placental maturity is not associated with aberrant fetal growth.

Survival of cells in suspension culture after treatment with damaging agents is usually measured by extrapolation from growth curves or by growth of colonies in soft agar. We have developed a survival assay which measures the ability of small numbers of cells to initiate microscopic cultures in wells of microtiter plates without agar or feeder layers. Suitable human lymphoblastoid lines were obtained by selection of rapidly growing cultures from microtiter wells in which < 200 cells were inoculated in 0.2 ml RPMI 1640 medium and incubated at 37 degrees with 5% CO2 at 95% relative humidity. Survival after damage was measured by inoculating groups of 24 microtiter wells with appropriate serial dilutions of cells. The wells were examined microscopically at intervals and scored for evidence of cell proliferation. Survival was calculated with the Poisson formula on the basis of the fraction of wells in which cells were not proliferating. Survival did not change appreciably after 2--3 weeks incubation. Survival measured by the microtiter-well assay was found to be similar to survival measured by extrapolation from growth curves after damaging the cells with bleomycin or with 8-methoxypsoralen plus long-wavelength ultraviolet radiation. The microtiter-well assay affords a simple, accurate measure of cell survival in human lymphoblastoid cells with suitable growth ability.

Psychosocial profiles were done prospectively on 54 males and three females in addition to hemodynamics and non-invasive studies; the average age at admission was 44 years. The mean study time for 45 survivors was two years and three months and was seven months for 12 non-survivors. Thirty potential psychosocial problems were investigated during coronary care unit stay, and at three months, six months, and one year. Four problems previously shown to have prognostic significance were re-examined. Depression and pessimism occurred more frequently in non-survivors (α = .05). Patients with maladaptive family relationships post-admission were more likely to die (66 percent), than those with adaptive relationships (15 percent) (α = .05). Patients with poor social adaptation prior to admission had significantly more psychosocial problems during follow-up (α = .05). However, this group had no more deaths than the total population. The type and number of psychosocial problems of survivors and non-survivors of acute myocardial infarction have predictive prognostic value.

A 38-year-old black woman with thyrotoxicosis, whose first symptom was angina pectoris, is described. Chest pain became progressively more frequent, and an unstable angina pattern developed. Angina attacks were associated with transient ischemic electrocardiographic changes and recurrent ventricular tachycardia was documented. Coronary angiography revealed no significant obstructive lesions. The patient became free of pain with antithyroid treatment and angina has not recurred.It is important to recognize that angina pectoris may be the major presenting symptom of thyrotoxicosis; unstable angina requires careful work-up and management including the performance of coronary angiography.

Thallium 201 myocardial perfusion scanning revealed focal left ventricular defects at rest in four of 30 patients (13 percent) with systemic sarcoidosis. All the defects decreased in size during thallium stress imaging, a finding opposite of that usually seen in myocardial ischemia. Nine patients had abnormal right ventricular visualization at rest. Thus, 11 of 30 (37 percent) had abnormal resting myocardial scand. Two of the four patients with left ventricular defects were studied serially for up to 1.5 years to evaluate response to corticosteroid therapy. The myocardial defect diminished in one patient, whereas the second patient, maintained for 2 years on low doses of steroids, had no resolution. In patients suspected of focal myocardial involvement by sarcoidosis on thallium scanning dynamic changes in scan defects can occur during exercise which are the reverse of those usually seen in coronary artery disease. These defects probably represent myocardial sarcoid. Right ventricular uptake generally appears to correlate with the severity of pulmonary involvement by sarcoidosis, yet does not appear to be a specific finding.

Fetal weight estimation was performed in 58 women with preterm premature rupture of the membranes within 4 days of delivery. Of twelve formulas evaluated, only two met the requirements for clinical use (i.e., they had a small mean percent error and a high correlation). However, both had high random error, which may be attributable to the very low birth weights studied. (Am J Obstet Gynecol 1989;160:1150-4.)

The QRS portion of the electrocardiogram of the complexes of patients were sampled at the rate of 1024 samples per second. The power spectral densities were calculated using the fast Fourier transform on a quarter of a second portion of an FM recorded ECG, centered on the peak of the R wave. It was discovered that in a typical QRS complex of normal duration, virtually all of the power is contained in frequencies below 30 Hz with peak power occurring in the range of 4 to 12 Hz. It should be noted that the frequency corresponding to the location of the peak is the heart rate of the patient. Furthermore, most noticeably, premature ventricular contractions typically contain less high frequency power than normal beats, with virtually all the power contained in frequencies below 12 Hz with peak power located at about 4 Hz. Finally, notches in some QRS complexes was associated with a broadened distribution of power in the power spectral density even though the tail from 30-100 Hz contained relatively less power than that contained in the frequency band below 30 Hz.

Twenty-one patients with acute anterior myocardial infarction had precordial ST segment mapping, using a system of 42 leads, at 0, 2, 4, 8, 24, and 48 hours (control group). Eleven patients (treatment group) had maps on admission and after 30-45 minutes; then serial maps were performed at similar intervals after 5-10 mg of isosorbide dinitrate (ISD). There were no significant differences in age, sex, functional class, mean time elapsed between onset of chest pain and admission, and inhospital mortality between the groups. Controls had a higher incidence of recurrent MI (6 patients vs 2) compared with the ISD group (P less than 0.05).The sum of ST segment elevations in all leads (ΣST) was similar in both groups on admission and remained at the same level in controls for 48 hours. One hour after ISD the blood pressure decreased significantly; ΣST and the number of leads with more than 1 mm ST elevation (NST) decreased significantly (62±10 to 31±4 / 26±1 to 19±2) (P less than 0.01). In the ISD group serial ST maps showed significant decreases (52±5 vs 28±4; 44±4 vs 26±2; 45±4 vs 29±3; 51±5 vs 28±3, 52±8 vs 28±2, respectively at 2, 4, 8, 24 and 48 hours), suggesting reduction of ischemic injury by ISD.Estimation of infarct size (in units from R wave height and Q and S wave depths in leads I, AVL and V(1)-V(6)) indicated a reduction in the ISD group on days one, two and seven. Total CPK, SGOT and LDH levels were similar on admission; at 24 and 48 hours after admission CPK values were not significantly different but SGOT and LDH were lower in the treated group.

1. An enzyme that degrades proteoglycan at neutral pH was extracted with 4 M-guanidine hydrochloride from the articular cartilage of rabbits with antigen-induced arthritis. 2. The enzyme had an apparent molecular weight on Ultrogel AcA 54 of about 8000 and was optimally active at pH 7.5 in Tris/HCl buffer containing 0.2 M-NaCl. The partially purified preparation was totally inhibited by 0.01 mM-N-acetyldialanylprolylvalylchloromethane, severely inhibited by 2 mM-phenylmethanesulphonyl fluoride and soya-bean trypsin inhibitor (200 microgram/ml) and slightly inhibited by 10 mM-EDTA. Marked inhibition was also obtained with a cytosolic fraction prepared from rabbit polymorphonuclear leucocytes. 3. All properties of the enzyme were virtually identical with those of an ‘elastase-like’ proteinase that was isolated from rabbit polymorphonuclear-leucocyte granules. 4. The results are consistent with the idea that cartilage proteoglycan degradation in acute joint inflammation is due at least partly to the diffusion into the cartilage of proteinases derived from synovial-fluid polymorphonuclear leucocytes.

Term, large for gestational aged newborns were retrospectively evaluated. The fetal parameter of relative growth, was measured using the ratio of fetal length to abdominal circumference (FL/AC). This measurement was not different between diabetic and nondiabetic gravidas who delivered LGA infants when ultrasound was obtained within 1 week of delivery.

A survey of hepatitis B patients, asymptomatic hepatitis B antigen (HBsAg) carriers, and control subjects was conducted to determine the relationship between antigenemia and antigen excretion in saliva, urine, and stool. Radioimmunoassay was used to detect HBsAg. Specificity-confirmed HBsAg was detected in the saliva of 6 (30%) of 20 antigenemic patients, 1 (5%) of 20 nonantigenemic patients, 14 (34%) of 41 carriers, and 0 of 112 controls. HBsAg was detected in urine only after 100-fold concentration of first-morning specimens. Specificity-confirmed HBsAg was present in the urine of 7 (16%) of 43 carriers; unconfirmed HBsAg was found in the urine of 5 (13%) of 38 patients and 5 (5%) of 112 controls. Unconfirmed HBsAg was detected in concentrated stool specimens from 5 (46%) of 11 patients and 3 of 8 carriers and controls. Longitudinally collected specimens from antigenemic subjects showed no consistent patterns of antigen excretion.

An overview of the problems and management of acute myocardial infarction is presented. Certain factors that are pertinent to the problem of differential mortality in various population subgroups have been identified. These factors include race, sex, and socioeconomic background.