Early bladder outlet obstruction in fetal lambs induces renal dysplasia and the prune-belly syndrome

A model of posterior urethral valves in fetal lambs was developed in order to evaluate the effect of intrauterine urinary obstruction on the developing kidney. Complete urethral obstruction was induced in five fetal lambs at 43 to 45 days of gestation. Two control fetal lambs underwent sham operations. At full term (140 days), two of the five experimental lambs and both control lambs were available for postmortem examination. Results of gross and histological examination of the control lambs were normal. In contrast, the kidneys of the experimental lambs were markedly asymmetrical in size. Histological examination of the kidneys in experimental lambs showed cystic dilatation of the collecting ducts and occasional cystic dilatation of Bowman's spaces, features compatible with obstruction. Also noted were peripheral cortical cysts and primitive tubules lined with cuboidal epithelium and surrounded by fibromuscular collarettes, characteristic of renal dysplasia. One of the infant lambs had many characteristics of the prune-belly syndrome, including a wrinkled, markedly distended abdomen, deficient abdominal wall musculature, flared chest wall, limb deformities, and undescended testes. These results suggest that early in utero urethral obstruction (at the beginning of the second third of gestation) causes renal dysplasia. The results also support the hypothesis that the prune-belly syndrome results from abdominal distention that occurs early in gestation.     

The effect of the number of electrocardiograms analyzed on cardiovascular disease surveillance: the Minnesota Heart Survey (MHS)

One method used to control costs in community cardiovascular disease surveillance is to limit the number of electrocardiograms (ECGs) used to validate acute myocardial infarction (AMI). The Minnesota Heart Survey investigated the impact of decreasing the maximum number of ECGs analyzed on classification of ECG pattern and final AMI diagnosis (definite, probable, none). A 50% sample of all 1980 acute CHD hospital discharge records (ICD-9 code 410 or 411) from 30 of 31 Twin Cities hospitals were abstracted. Comparing results using all available ECGs in the record (maximum of 12) with those obtained using up to 4 ECGs showed little differences in the ECG classification or final AMI diagnosis.     

Blood flow acceleration in the carotid and brachial arteries of healthy volunteers: respective contributions of cardiac performance and local resistance

Summary— The influence of local resistance and cardiac performance on peripheral blood acceleration was investigated in 14 healthy male volunteers. Steady and pulsatile flow was studied in the brachial and in the common carotid arteries, ie, two territories that exhibit marked differences in resistive characteristics. Instantaneous blood velocity (V), mean blood velocity (V_m) and artery diameter (D) were evaluated at rest by an ultrasonic range-gated pulsed Doppler flowmeter using a double transducer probe, thus allowing the calculation of mean blood flow (Q). Mean local resistance (R) was obtained by dividing the mean arterial pressure by Q. The peak value of the local acceleration of the blood was obtained by computer-assisted calculation of the first derivative of instantaneous blood velocity (G_max = +dV/dt_max). Peak aortic blood acceleration (GAo) was simultaneously measured from the suprasternal notch using a pulsed Doppler velocity meter. In the brachial and the common carotid arteries, G_max was of a similar magnitude (551 ±30 and 555 ± 44 cm/s², respectively) despite major differences in the respective D, V_m, Q and R values. In neither artery was there a relationship between G_max and either resting Q or R. At the brachial artery level, G_max was positively related to GAo ( r = 0.79, P = 0.0008). At the common carotid artery level, there was a weak, although non significant relationship between G_max and GAo ( P = 0.08). Our results indicate that the local acceleration of peripheral blood flow in the brachial artery is related rather to upstream central impulse than to downstream hemodynamics, and suggest some regional differences in the hemodynamic determinants of the local acceleration of peripheral blood flow.     

Mucous cyst of the distal interphalangeal joint: treatment by simple excision or excision and rotation flap

Thirty-five patients who had thirty-seven mucous cysts excised from the distal interphalangeal joints were reviewed not less than one year later. Seven out of 25 which had been treated by simple excision recurred, whereas only one out of twelve treated by excision and skin closure with a rotation flap recurred.     

Anti-estradiol immunoperoxidase labeling of nuclei, not cytoplasm, in paraffin sections, determines estrogen receptor status of breast cancer

We evaluated a commercially available polyclonal antibody to 17 beta-estradiol as the basis for an estrogen receptor (ER) assay of breast carcinoma in formalin-fixed paraffin tissues and then compared it with both the ER-ICA antibody in serial paraffin sections and the biochemical assay of corresponding fresh tissue. Using the estradiol antibody, 49 of 50 cases showed some cytoplasmic staining; 38 cases had nuclear staining. Sensitivity and specificity for different proportions of positive nuclear and cytoplasmic staining were calculated using receiver-operator characteristic curves. The optimum correlation with the biochemical assay was obtained with nuclear staining alone. Greater than 30% nuclear positivity as a cut-off point yielded a sensitivity of 76% and a specificity of 82%. The corresponding ER-ICA values in 38 cases yielded a sensitivity of 93% and a specificity of 56%. The methodology for the ER-ICA assay was more technically demanding in paraffin sections than that of the estradiol antibody and considerably more expensive. This study is the first to show that with nuclear staining only, and not cytoplasmic staining, as the parameter of positivity, the immunocytochemical assay of ER with anti-17 beta-estradiol antibody in routinely processed, formalin-fixed, archival material is an accurate and specific method for the determination of the ER status of breast carcinoma.     

CT appearance of cervical lipoblastoma

We describe a case of lipoblastoma causing respiratory symptoms in an infant, where CT was useful in establishing the diagnosis and demonstrating the extent of involvement so that complete surgical resection could be planned.     

Glutathione localisation in benign and malignant human breast lesions

Reduced glutathione (GSH) has been demonstrated in benign and malignant human breast lesions using a newly developed histofluorescence technique. GSH was present in every lesion and in each case was localised to the epithelium. A semi-quantitative assessment revealed a moderate amount of GSH in normal epithelium and fibroadenoma and a high level in apocrine metaplasia, epitheliosis and intraduct carcinoma. Invasive ductal carcinoma contained a variable amount of GSH. Correlation between fluorescence intensity and histological grade of ductal carcinomas was almost statistically significant but a relationship to oestrogen receptor status was not detected. The rapid assessment of GSH in breast cancer may aid in the selection of optimum chemotherapeutic regimens.     

Mitogenic activity and receptor reactivity of hybrid molecules containing portions of the insulin-like growth factor I (IGF-I), IGF-II, and insulin molecules

Insulin and the insulin-like growth factors IGF-I and IGF-II are thought to exert their mitogenic effects in cultured chick embryo fibroblasts and human skin fibroblasts via IGF receptors rather than via insulin receptors. These effects appear to be mediated by the type I subtype of IGF receptor, which is structurally similar to the insulin receptor and exhibits significant cross-reactivity with insulin. As a first step in our long-range goal of defining those features of the IGF-I and IGF-II molecules that confer enhanced mitogenic activity and reactivity with these mitogenic type I IGF receptors, we have prepared two hybrid insulin-IGF molecules and examined their mitogenic and binding activities: (1) A27-insulin, containing an elongated 27-residue A-chain (in which the 6-residue D-domain of IGF-II was added to the carboxy-terminus of the 21-residue A-chain of insulin) combined with the B-chain of insulin; and (2) A insulin-B IGF-1, containing the A-chain of insulin and the synthetic 30-residue B-domain of IGF-I. Both hybrid molecules stimulated DNA synthesis and inhibited 125I-IGF-I binding to type I IGF receptors in both chick embryo and human fibroblast cultures. A27-insulin had considerably greater mitogenic potency and binding potency than A insulin-B IGF-I. Neither hybrid molecule was more potent in these assays than insulin, indicating that the presence of D IGF-II or B IGF-I by itself was not sufficient to increase the mitogenic potency of insulin in fibroblasts. By contrast, A insulin-B IGF-I showed enhanced reactivity with an antiserum to IGF-I. A27-insulin retained significant insulin-like metabolic activity despite the presence of the D-domain of IGF-II.