Sources of amino acids for protein synthesis during early organogenesis in the rat. 2. Exchange with amino acid and protein pools in embryo and yolk sac

Tenth-day rat conceptuses were cultured in whole rat serum containing [3H]leucine and harvested after 24 or 48 h. Hydrolysates of the acid-precipitable fraction of embryo or yolk-sac homogenates were prepared and subjected to paper chromatography. Liquid scintillation counting of the separated amino acids showed that leucine was the only amino acid with above-background radioactivity. This established that radiolabel was not transferred from leucine to other amino acids in the cultured rat conceptus. Tenth-day rat conceptuses were cultured in whole rat serum containing [3H]leucine, as above. After 19 h, some conceptuses were harvested; other conceptuses were rinsed, transferred to culture medium without [3H]leucine, and after a further 24 h of culture the embryos and yolk sacs were harvested. A comparison of the protein-associated radioactivity of embryo and yolk sac before and after culturing for the further 24-h period showed that these structures quantitatively conserve radiolabelled leucine incorporated into their proteins. Further experiments involved culturing the rat conceptus for 24 h as above but in the presence of either [3H]leucine or [3H]leucine-labelled serum proteins. After harvesting the conceptuses, the specific radioactivity of [3H]leucine was determined in the acid-soluble and acid-precipitable fractions prepared from embryo and yolk-sac homogenates. The specific radioactivity of [3H]leucine in the acid-soluble fraction of embryos or yolk sacs from conceptuses grown in the presence of radiolabelled protein was about 120 per cent of that in the culture medium, while that in the acid-precipitable fractions was about 70 per cent of that in the culture medium. By comparison, the specific radioactivity of [3H]leucine in the acid-soluble fraction of embryos and yolk sacs from conceptuses grown in the presence of free [3H]leucine was only 3-4 per cent of that in the culture medium, while that in the acid-precipitable fraction was about 1 per cent of that in the culture medium. If our data on the fate of leucine incorporated into newly synthesized proteins of the early post-implantation rat embryo can be extrapolated to the other amino acids, they suggest that once amino acids have been incorporated into newly synthesized protein in embryo or yolk sac, they are not exchanged to any detectable extent with amino acid pools outside the conceptus. The results also provide independent confirmation of our earlier conclusion that the only significant source of amino acids utilized by the 10th-day embryo is protein taken up by the yolk sac and digested intracellularly.(ABSTRACT TRUNCATED AT 400 WORDS)     

Otoacoustic emissions as a screening test for hearing impairment in children

Transient evoked otoacoustic emissions (TEOAEs) are low amplitude sound waves produced by the healthy cochlea. They can be recorded with a microphone in the external ear. TEOAEs are abolished by hearing losses of 30 dB or more. The feasibility of using TEOAEs as a screening test for hearing loss in children was studied. TEOAE recordings were attempted in 56 children attending an audiology clinic. Recordings were possible from both ears in 52 children; of these 104 ears, 32 had hearing deficits of 30 dB or more. Hearing status was compared with the results of six TEOAE screening criteria. All criteria had a sensitivity of 1.00. Four standard TEOAE criteria yielded specificities of 0.46-0.58. Two new criteria derived from analysis of limited frequencies from the TEOAE waveform gave specificities of 0.76 and 0.82. It can be concluded that, when appropriate pass/fail criteria are employed, TEOAEs are a feasible screening test in children.     

Pelvic ultrasound findings in different forms of sexual precocity

Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty.     

Endometrial carcinoma presenting with ascites

Three examples of endometrial carcinoma presenting with ascites are reported. The patients were in the eighth decade, had no vaginal bleeding, and were considered to have ovarian cancer preoperatively. Laparotomy revealed gross omental tumor and normal appearing ovaries. The endometrial cancers were grossly undetected and were uniformly noninvasive of the myometrium. They projected into the uterine cavity, two in polyps, and one covering a submucous leiomyoma. The fallopian tubes were the most likely route of spread to the abdominal cavity.     

Colposcopic screening of women with atypical Papanicolaou smears

A retrospective study was done on 575 patients with atypical Papanicolaou smears obtained during a ten-year period (1974-83) at Bellevue Hospital-New York University Medical Center. The smears were classified into three categories. The first consisted of 463 patients (81%) with inflammatory atypia specifically treated for Trichomonas, Monilia, Chlamydia, Gardnerella and atrophic vaginitis. Of them, 162 patients (35% of the group) had persistent inflammatory atypia 90 days after the beginning of therapy and were subjected to colposcopic examination. The second group consisted of 86 patients (15%) with squamous atypia. That group underwent colposcopic examination. The third group, 26 patients (4%), had endocervical atypia and underwent colposcopy and endocervical curettage. Overall, of 162 patients with persistent inflammatory atypia, 36 (22%) were found to have cervical intraepithelial neoplasia (CIN); of 86 with squamous atypia, 60 (70%) had CIN; and of 26 with endocervical atypia, 15 (58%) had CIN. Fifty-eight (28%) of all the patients with CIN had lesions of severity greater than CIN 1. It appears that all patients with persistent inflammation or squamous or endocervical atypia would benefit from colposcopic screening.     

Uterine arteriovenous malformation successfully embolized with a liquid polymer, isobutyl 2-cyanoacrylate

A uterine arteriovenous malformation was diagnosed angiographically in a 27-year-old woman presenting with recurrent menometrorrhagia. Bilateral hypogastric artery embolization with a liquid polymer, isobutyl 2-cyanoacrylate (Bucrylate), resulted in subsequent normal menses. Bucrylate offers a number of advantages over other agents previously used to embolize uterine arteriovenous malformations.     

Standard versus fiberoptic pulmonary artery catheterization for cardiac surgery in the Department of Veterans Affairs: a prospective, observational, multicenter analysis

BACKGROUND: Controversy exists regarding the utility of continuous monitoring of mixed venous oxygen saturation (STvo2) during cardiac surgery. During a multicenter, prospective, observational study in the Department of Veterans Affairs (Cooperative Study #5), frequency of use of standard pulmonary artery catheterization (PAC) and STvo2-PAC was recorded. Here the authors relate these data to clinical outcomes. METHODS: Logistic and Cox regression models evaluating the association of PAC type with mortality, one or more postoperative complications, cardiac complications, time to extubation, and intensive care unit length of stay were constructed. The number of thermodilution cardiac outputs and arterial blood gas analyses performed in the first 24 h postoperatively were compared. RESULTS: Data from 3,265 patients undergoing myocardial revascularization (81.7%) or valve replacement-repair (18.3%) were considered. STvo2-PAC was used in 49% and PAC in 51% of patients. In the 14 hospitals, STvo2-PAC was used in all patients in four, in some patients in four, and never in six. No association of STvo2-PAC use with outcome were observed aside from unexplained hospital level effects. A small but statistically significant reduction in the number of arterial blood gas analyses (8 +/- 3 vs. 10 +/- 4, P < 0.0001, STvo2-PAC vs. PAC, respectively) and thermodilution cardiac outputs (14 +/- 8 vs. 15 +/- 9, P < 0.0001, STvo2-PAC vs. PAC, respectively) was observed with use of STvo2-PAC. CONCLUSIONS: Despite higher cost, STvo2-PAC was commonly used in this cohort. Our analysis failed to detect associations with improved outcomes aside from a small reduction in resource utilization. The precise role of STvo2-PAC remains uncertain.     

Dose-image optimisation in digital radiology with a direct digital detector: an example applied to pelvic examinations

In diagnostic radiology increasing attention has been focused on dose reduction while maintaining a clinically good image quality. With the use of digital detectors balancing dose vs image quality is done differently than in film-screen radiography, since dose and image brightness are uncoupled in digital imaging. In this study a new direct digital detector (flat-panel detector) was used in a dose-image optimisation of a simulated pelvic examination. X-ray images were taken with a direct digital detector (DDD), of the pelvic of a phantom using varying tube current (varying stochastic noise). The entrance surface dose was measured for each image. These images were scored by two radiologists according to EU guidelines. A dose comparison was made with an older PCR system (storage phosphor plates). With decreasing tube current the noise in the images increased and the image with the lowest dose and still acceptable image quality was identified. The results showed that the entrance surface dose using the DDD decreased from 1.4 mGy (PCR value) to 0.48 mGy (DDD standard settings). Through the optimisation the dose could be further decreased to 0.24 mGy while still maintaining an acceptable image quality. A substantial dose reduction was obtained with this new direct digital detector. This simple but efficient optimisation approach is easily applicable to other examinations and both DDD and storage phosphor plate detectors.     

Technique for using video microscopy and indicator dilution for repeated measurements of cardiac output in small animals

BACKGROUND: The authors developed an indicator dilution technique for small animals to repeatedly determine cardiac output and blood volume without cardiac instrumentation or blood sampling. METHODS: Observations were made in the hamster (N = 32, 70 mg/kg pentobarbital) cremaster using in vivo fluorescence videomicroscopy. Fluorescein isothiocyanate-conjugated bovine serum albumin (10 mg/ml) was injected as a bolus dose (right jugular) while video recording the light intensity in a 20-microm arteriole (intensified charge-coupled device [CCD] camera at fixed gain). The intensity signal was analyzed over time (background subtracted) and calibrated to the dye concentration. The ex vivo calibration was performed using a constant optical path length (20 microm) and a range of dye and hematocrit concentrations. In vivo tube hematocrit was determined using standard methods with fluorescently labeled erythrocytes. Thus, quenching of the fluorescence signal by hemoglobin was corrected for the calibration, and the plasma space in the arteriole was determined. The steady state dye concentration measured by the light intensity at 2 min was not different from the dye concentration found by direct spectrophotometric analysis of the plasma. RESULTS: Cardiac index was calculated as milliliters of blood per minute per kilogram body weight. The calculated cardiac index was 359 +/- 18 ml.min(-1).kg(-1), which is not different from the reported values for hamsters. Cardiac output was increased twofold when enough intravenous nitroprusside or nitroglycerine was injected to decrease mean arterial pressure from 90 to 70 mmHg. Cardiac output was elevated during dobutamine infusion (16 microg.kg(-1).min(-1)) and decreased during esmolol infusion (50, 75.kg(-1).min(-1)). Blood volume determined from the steady state dye concentrations was 6.2 +/- 0.5 ml/100 g body weight, within the normal range for hamsters. CONCLUSIONS: Fluorescent dye dilution and video microscopy can be used to repeatedly determine cardiac output or blood volume in small animals.     

Acceptability of suction curettage and mifepristone abortion in the United States: a prospective comparison study

OBJECTIVE: We sought to compare the acceptability of suction curettage abortion with that of medical abortion with mifepristone and misoprostol in American women. STUDY DESIGN: We performed a prospective, serially enrolled, cohort analysis. The study population consisted of 152 subjects receiving mifepristone and misoprostol and 174 subjects undergoing suction curettage abortion aged > or =18 years with intrauterine pregnancies of up to 63 days' estimated gestation. Questionnaires regarding expectations and experiences were administered before the abortion and at the 2-week follow-up visit. RESULTS: Subjects undergoing medical abortions reported significantly greater satisfaction than those undergoing surgical abortions (mean rank, 121 vs 149; P <.01) but were no more likely to recommend the method they had just experienced to a friend (97% vs 93.3%). If a future abortion was required, however, 41.7% of subjects undergoing surgical abortions indicated they would opt for a medical abortion, whereas only 8.6% of subjects receiving medical abortions would choose a surgical abortion (P <.001). Failure of the abortion decreased satisfaction in the medical group and increased the likelihood of choosing a surgical abortion for a subsequent procedure (P <.001). Surgical subjects who experienced more anxiety than expected during the abortion were more likely to choose a medical procedure for a subsequent abortion (P <.01). CONCLUSION: Women receiving mifepristone and misoprostol were more satisfied with their method and more likely to choose the same method again than were subjects undergoing surgical abortion. Failure of a medical abortion and increased anxiety during surgical abortion were associated with preference for the alternative technique in a future procedure.