Temporal relationships between plasma cortisol, corticosteroid-binding globulin (CBG), and the free cortisol index (FCI) in pigs in response to adrenal stimulation or suppression

The objective of this study was to document changes in plasma concentrations of total cortisol, porcine corticosteroid-binding globulin (pCBG), and the free cortisol index (FCI) in pigs over a 6-h period in response to adrenal stimulation or suppression. Twenty-four 8-week old pigs allotted in equal numbers were administered ACTH, dexamethasone or saline, and blood samples were collected every 15 min via an indwelling jugular catheter for 1 h prior to and 5 h following treatment. Total plasma cortisol increased in ACTH-treated pigs and decreased in dexamethasone-treated pigs within 0.25 and 0.5 h, respectively. In contrast, pCBG concentration was altered in an inverse fashion subsequent to the changes exhibited in total cortisol. FCI reflected the changes observed in total cortisol. These results further document the negative relationship that exists between circulating concentrations of plasma cortisol and pCBG, and illustrate that this association exists under conditions of acute stress in the pig.

Hormonal profiles, behavioral responses, and short-term growth performance after castration of pigs at three, six, nine, or twelve days of age

The objective of this study was to determine the effects of castration on short-term growth performance, hormone profiles, and behavior in pigs at 3, 6, 9, or 12 d of age. Ninety intact male pigs were assigned randomly to a treatment age by litter [3, 6, 9, or 12 d of age; n = 9 to 13 pigs per treatment (age) group]. Pigs within a single litter were then assigned to noncastrated (NC) or castrated (CAS) treatment groups according to BW. Pigs were nonsurgically fitted with jugular catheters, and blood samples were drawn immediately before castration (0 h) and at 0.5, 1, 1.5, 2, 24, and 48 h after castration. Body weights were obtained when pigs were catheterized and again at 24 and 48 h after castration. Serum samples were analyzed for cortisol, porcine corticosteroid-binding globulin, and dehydroepiandrosterone sulfate (DHEA-S). No differences were detected in initial BW of pigs, and there was no overall treatment effect on growth performance of pigs at 24 or 48 h posttreatment. A time x treatment interaction was detected (P < 0.01) for serum cortisol concentrations, such that cortisol was greater in CAS pigs than in NC pigs. No overall effect of age at castration was observed on cortisol concentrations. At 24 h after castration, serum cortisol concentrations returned to baseline in all treatment groups; however, at 48 h after castration, overall cortisol concentrations were elevated (P < 0.01) in the 6-, 9-, and 12-d-old pigs in both the CAS and NC groups compared with baseline concentrations. Total cortisol and porcine corticosteroid-binding globulin were used to calculate the free cortisol index (FCI). A time x treatment interaction was observed (P < 0.01) for FCI, such that FCI was greater in CAS males than in NC males. The FCI was also affected by age (P < 0.01). There was a time x treatment x age interaction (P < 0.01) for serum DHEA-S, such that DHEA-S concentrations decreased in CAS animals but increased in NC animals, and DHEA-S concentrations increased with age. During the first 2 h after castration, there was an overall age effect (P = 0.01) on the time that pigs spent standing, such that 3-d-old pigs stood more than 6-, 9-, or 12-d-old pigs. Treatment did not influence the time that pigs spent nursing, lying, standing, or sitting, although there was a trend (P = 0.08) for CAS pigs to be less active than NC pigs. These data indicate that castration is stressful regardless of age; however, the stress associated with handling seems to increase as pigs age.

Hepatic corticosteroid-binding globulin (CBG) messenger RNA expression and plasma CBG concentrations in young pigs in response to heat and social stress1,2

Plasma cortisol, porcine corticosteroid-binding globulin (pCBG), hepatic CBG expression, and other physiological and behavioral measures of stress were studied in pigs in response to elevated temperature in conjunction with establishing a social hierarchy. Twenty-four crossbred pigs were weaned at 25 d of age (three or six pigs from six sows) and housed in littermate groups at 23 +/- 2 degrees C. At 57 d of age (d 0), animals were weighed and placed under general anesthesia for collection of blood (10 mL) and liver (approximately 100 mg) samples. On d 1, three unacquainted pigs of similar BW (23 +/- 1 kg) from different litters were allotted to each of eight nursery pens within two environmentally controlled rooms (12 pigs per room). From d 1 to 7, one room was maintained at 23 +/- 2 degrees C (CON) and the other at 33 +/- 2 degrees C (HEAT). Both rooms were kept at 23 +/- 2 degrees C from d 8 to 14. Animals were videotaped for 72 h beginning on d 1 and 8 to document behavioral changes in response to room temperature. The social hierarchy of pigs within each pen was based on fight activity recorded on d 1 to 3. Blood and liver tissue were collected again on d 7 and 14. The ADG for HEAT pigs increased (P < 0.05) over d 8 to 14 compared with d 1 to 7. In contrast to CON pigs, HEAT pigs displayed increased (P < 0.01) drinking but decreased feeding and lying in contact with other pigs from d 1 to 3, and similar drinking and feeding but increased (P < 0.01) lying with contact behaviors from d 8 to 10. With the exception of subordinate pigs exhibiting less (P < 0.05) frequent standing/walking behavior than the dominant or intermediate pigs on d 1 to 3, frequency of behaviors for both recorded time periods did not differ among pigs due to social status, regardless of treatment. The concentration of plasma haptoglobin in HEAT pigs on d 7 compared with d 0 increased (467 vs. 763 mg/L; P < 0.05), whereas cortisol and pCBG decreased (274 vs. 235 nmol/L and 11.4 vs. 9.9 mg/L, respectively; P < 0.05) as a result of treatment. The free cortisol index (total cortisol/pCBG) was greater (P < 0.05) in HEAT pigs on d 14 than on d 0 or 7. Hepatic CBG mRNA level was not affected by treatment. On d 14, HEAT pigs had plasma cortisol, pCBG, and haptoglobin concentrations similar to those of CON pigs. These results indicate that measured behavioral and physiological responses were not related to social status, and decreased circulating levels of cortisol and pCBG in pigs following a 7-d exposure to elevated temperature may not be determined by hepatic CBG mRNA expression.

Age-related changes in porcine corticosteroid-binding globulin (pCBG) as determined by an enzyme-linked immunosorbent assay

The objectives of this study were to develop an assay for the direct measure of porcine corticosteroid-binding globulin (pCBG) and to confirm age-related changes in plasma pCBG concentration. Isolation and purification of pCBG from plasma was performed by affinity chromatography and HPLC-DEAE anion exchange techniques. Analysis by SDS-PAGE revealed two polypeptides (54 and 59 kDa) having similar amino acid homology (>50%) to previously reported sequences of seven mammalian species for the first 33 amino acids. Porcine CBG (20 ng/well) was immobilized to microtiter plates and standards or samples added along with rabbit antiserum developed against the purified pCBG. Goat anti-rabbit IgG-alkaline phosphatase conjugate was added followed by p-NPP substrate. The resultant color development was read at 405 nm. Intra- and interassay coefficients of variation (n=26) of a pooled sample were 10 and 15%, respectively. Age-related changes (P<0.001) in plasma pCBG concentration (n=203) from day 3 through 168 of age confirmed that, in the pig, changes seen in the percent distribution of cortisol among protein bound and free forms around day 28 of age are associated with an increase in CBG concentration.

Effect of menhaden fish oil supplementation and lipopolysaccharide exposure on nursery pigs. I. Effects on the immune axis when fed diets containing spray-dried plasma

The objective of the present study was to evaluate the potential immunological benefit of adding menhaden fish oil to the diet of weaned pigs. Twenty-four crossbred male pigs were weaned at approximately 18 days of age and placed on a complex nursery diet containing 30% lactose and 7% plasma protein with 6% corn oil as the fat source (Cont, n=12) or with 5% menhaden fish oil and 1% corn oil as the fat source (MFO, n=12) for a period of 15 days. Body weights did not differ (P>0.78) between dietary groups either at the beginning or end of the 15 days feeding period. On day 15, all pigs were non-surgically fitted with an indwelling jugular catheter. On d 16, pigs received an i.v. injection of either saline (n=6/dietary group) or lipopolysaccharide (LPS; 150 microg/kg body weight; n=6/dietary group) and blood samples were collected at 30 min intervals for a period of 5h. Serum was harvested and stored at -80 degrees C for analysis of cortisol (CS), corticosteroid-binding globulin (CBG), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). There was no significant effect of diet on basal concentrations (Time 0) of any of the blood parameters analyzed. A Time x Treatment x Diet interaction (P<0.03) was observed for serum CS such that those pigs which consumed the MFO diet followed by LPS treatment had a reduced CS response as compared to the LPS-treated pigs on the Cont diet. A Time x Treatment interaction (P<0.01) was observed for serum CBG such that LPS treatment reduced circulating CBG as compared to the saline-treated pigs. Time x Treatment x Diet interactions were also observed for serum concentrations of TNF-alpha (P=0.084) and IFN-gamma (P=0.022) such that both the TNF-alpha and IFN-gamma response to the LPS challenge was lower in those pigs receiving the MFO diet as compared to the LPS-treated pigs on the Cont diet. Overall, serum CS was negatively correlated with the CBG response (r=-0.40, P<0.001), however, the strongest negative correlation was observed in the LPS-treated pigs which consumed the MFO diet (r=-0.63, P<0.001). While further studies are needed to evaluate the immunological response of including MFO in the nursery pig diet, the present study demonstrates that supplementation with MFO does indeed alter the immunological response to an LPS challenge.

The effects of split marketing on the physiology, behavior, and performance of finishing swine

One hundred twenty 8-wk-old barrows (20.3 +/- 2.0 kg BW) were used to examine the effect of split marketing on selected behavioral, physiological and performance parameters. Pigs were assigned by weight in a randomized complete block design to one of three treatments: SM (split-marketed), six pigs/pen (1.83 m2/pig); C (control), six pigs/pen (1.83 m2/pig); or MC (modified control), three pigs/pen (3.66 m2/pig). The heaviest half of SM animals were removed 1 wk prior to marketing penmates. Control and MC animals remained in their respective groups until marketing. Animals were videotaped during the first 72 h of the study (INITIAL), 72 h prior to (PRE), and following the removal (POST) of pigs in the SM treatment to quantify maintenance behaviors and to identify socially dominant, intermediate, and submissive pigs. A blood sample was collected from each animal upon completion of INITIAL, PRE, and POST time periods to determine neutrophil:lymphocyte ratio and plasma haptoglobin, cortisol, and corticosteroid-binding globulin (CBG) levels. Animals were weighed and feed disappearance was calculated biweekly. Tenth-rib backfat and area of the longissimus muscle at marketing were ultrasonically evaluated on all animals. Regardless of treatment, animals were more (P < 0.01) active (eating, standing/walking, fighting) at INITIAL than at PRE or POST times. Frequency and duration of fights per pen were less (P < 0.01) in MC than in C or SM pigs for all periods observed. Neutrophil:lymphocyte ratio, plasma haptoglobin, and CBG levels were greater (P < 0.01) during the INITIAL period than during the PRE or POST periods but did not differ between treatments. No treatment or time differences were detected in plasma cortisol levels. The MC pigs exhibited greater (P < 0.01) ADFI with poorer feed efficiency compared to C or SM pigs up to split marketing. During the POST period, both MC and SM pigs had greater (P < 0.01) ADFI with poorer (P < 0.01) feed efficiency than C pigs. The ADG was not different among animals as a result of treatment. There were no treatment differences for any of the carcass measurements. Significant differences in performance between the treatment groups could not be attributed to any physiological or behavioral measures reported here.

Influence of supplemental, dietary vitamin A on retinol-binding protein concentrations in the plasma of preruminant calves

Transport of retinol (vitamin A alcohol) from retinoid stores in the liver to target tissues is accomplished exclusively by a specific plasma protein, retinol-binding protein. Within individuals, retinol-binding protein concentrations in plasma are regulated and remain constant except in extremes of vitamin A nutriture or in disease. In the present study, retinol-binding protein concentrations in plasma from preruminant calves supplemented with 0, 1700 (i.e., current NRC requirement), 34,000, or 68,000 IU of vitamin A daily from birth to 27 d of age (n = 6/treatment) were quantified. Retinol-binding protein concentrations at birth averaged 21 microg/ml (n = 24) or approximately 50% of concentrations in dairy heifers and cows. Plasma retinol and retinol-binding protein concentrations were correlated positively, corroborating the role of vitamin A nutriture in the regulation of retinol-binding protein secretion from the liver. In this regard, dietary vitamin A influenced positively retinol and retinol-binding protein concentrations and, as a consequence, the degree of saturation of retinol-binding protein with retinol. At 27 d of age, calves fed > or = 34,000 IU of vitamin A had substantially higher retinol and retinol-binding protein concentrations than did calves fed < or = 1700 IU of vitamin A, indicating that dietary vitamin A effects positively vitamin A status. The data also suggest that the current NRC requirement may not be sufficient to assure vitamin A adequacy in preruminant calves. Percent saturation of retionol-binding protein with retinol in all calves was < 35%, much lower than anticipated and suggests that the retinol requirement of vitamin A-responsive tissues exceeded vitamin A availability.

Intrauterine cortisol, aldosterone, and corticosteroid binding globulin-like activity during early porcine pregnancy and the estrous cycle

Studies were conducted to determine whether the corticosteroids cortisol and aldosterone, and corticosteroid-binding globulin (CBG) were present in the porcine early-embryonic environment. Cortisol was measured in uterine flushings from white crossbred gilts at Days 7, 10, 13, and 16 of the estrous cycle and pregnancy. Total content of cortisol increased (p < 0.01) between Days 13 and 16, and immunoreactive CBG (ir-CBG) increased (p < 0.01) between Days 10 and 13, in both cyclic and pregnant gilts. In a separate study with Chinese Meishan gilts, total cortisol and aldosterone content of uterine flushings increased (p < 0.02) between Days 10 and 15 of the estrous cycle and pregnancy. In another study with white crossbred gilts, CBG-like binding activity in uterine flushings was low at Day 10, then increased over 100-fold at Day 15 (p < 0.01). However, levels of CBG-like binding activity on Day 15 were 100-fold lower than those of ir-CBG measured in the previous study and could bind less than 4% of the uterine luminal cortisol. Differences between ir-CBG and CBG binding might be due to the ability of the CBG antibody to recognize either biologically inactive CBG or structurally similar molecules. CBG-like binding activity, which appeared unrelated to glucocorticoid receptors, was also present in the endometrial cytosol of white crossbred gilts. Concentrations (fmol/mg protein) of endometrial CBG-like activity decreased (p = 0.03) between Days 10 and 15 of the estrous cycle and pregnancy, did not differ with reproductive status, and on Day 15 were comparable to concentrations in uterine flushings but threefold lower (p < 0.01) than those in the serum. Equilibrium dissociation constants for CBG-like binding activities were comparable among the three locations. These studies indicate that corticosteroids are present-primarily in the free form-within the porcine uterine lumen and could influence early porcine conceptus development. Endometrial CBG-like binding activity could mediate actions of cortisol or progesterone on uterine function.

Bovine endometrial retinol-binding protein secretion, messenger ribonucleic acid expression, and cellular localization during the estrous cycle and early pregnancy

Retinol-binding protein (RBP) mRNA was localized to luminal and glandular epithelial cells of bovine endometrium by in situ hybridization. Relative levels of endometrial RBP mRNA expression during the estrous cycle and early pregnancy were determined by quantitative slot blot analysis and contrasted with uterine luminal concentrations of RBP. Expression of mRNA was moderate at Day 1 after estrus, declined at Day 5, reached lowest levels by Day 10, rose significantly through Days 15-17, and peaked at Day 20. RBP mRNA expression in pregnant animals was similar to that in cyclic animals on Day 15, doubled between Days 17 and 20, remained constant through Day 22, and rose slightly thereafter. Luminal RBP concentrations of cyclic cows, as determined by ELISA, decreased from Day 1 through Day 10, rose dramatically on Day 15, then declined through Day 20. Concentrations of RBP in uterine flushes from pregnant animals were similar to those of cyclic cows on Day 15 but remained relatively constant through Day 17. It is concluded that 1) RBP synthesis occurs in the luminal and glandular epithelial cells, 2) RBP transcription and secretion are correlated with each other, and 3) ovarian steroids, possibly in conjunction with uterine concentrations of their receptors, modulate uterine RBP expression.

Development of invasive adenocarcinoma in a long-standing Kock continent ileostomy: report of a case

The first case of adenocarcinoma developing in a continent ileostomy is reported. A healthy, 39-year-old man with a continent ileostomy for 17 years developed subacute obstructive symptoms and was found on endoscopy to have a large adenocarcinoma involving the intussusception valve. At operation, he was found to have a large tumor originating in the valve, extending through the reservoir, and involving the afferent ileal limb. A number of metastatic lymph nodes were identified in the mesentery of the small bowel. He underwent excision of the pouch and formation of an end ileostomy. He is currently undergoing adjuvant chemotherapy. Biochemical and morphologic changes in the ileal pouch, both in the pelvis and the continent ileostomy, are discussed. The implications of this apparent de novo cancer arising in an ileal pouch are discussed.

Early gestational expression of retinol-binding protein mRNA by the ovine conceptus and endometrium

Communication between the mother and the early developing embryo is mediated by a variety of signals secreted by either the uterus or the embryo to elicit a response from the other. These signals include prostaglandins, proteins, and steroids. Recently, retinol-binding protein (RBP) has been described as a product of both the conceptus and endometrium in several species. Utilizing a cDNA clone to bovine RBP, we have described RBP mRNA expression in the endometrium, early conceptus, and extraembryonic membranes of sheep. Endometrial RBP mRNA expression did not differ between samples collected on day 13 of the estrous cycle and early pregnancy. In cyclic animals, RBP mRNA expression decreased two-fold between days 13 and 16, presumably a result of luteal regression and the consequential withdrawal of progesterone. In pregnant animals, endometrial RBP mRNA expression likewise decreased between days 13 and 16 and remained at this reduced level through day 30, despite the presence of a functional corpus luteum. Initiation of embryonic RBP expression appeared to coincide with early stages of blastocyst elongation at day 13. Levels of expression increased dramatically with conceptus development, peaked on day 23, and declined afterwards. Results from restriction enzyme analysis of genomic DNA indicated that RBP was encoded by a single gene per haploid genome. Differences in the temporal and tissue-specific expression of the protein, despite the apparent utilization of a single gene, suggest complex regulation of RBP gene expression.

Heparin treatment enhances the recovery of neoendothelial acetylcholine-induced vascular relaxation after balloon catheter injury in the rabbit aorta

BACKGROUND

After catheter injury, the neoendothelium that grows is abnormal in morphology and in acetylcholine-induced generation of endothelium-derived relaxing factor (EDRF). Heparin has been shown to have stimulatory effects on vascular endothelial growth in vitro. Its effect in vivo on neoendothelial cell morphology and metabolism after injury has not been described. We investigated the effect of heparin treatment on the neoendothelium formed after injury.

METHODS AND RESULTS

Four groups of New Zealand White rabbits were studied. Group 1 rabbits underwent catheter denudation and were killed 4 weeks after injury without receiving treatment (NO Tx, n = 8). Groups 2 and 3 underwent similar aortic injury, received 2 weeks of treatment with either heparin (n = 7) or low molecular weight heparin (LMWH, n = 5), and were killed at 4 weeks. Group 4 underwent sham operation (SHAM, n = 8). EDRF generation was determined by the relaxation of precontracted aortic rings in an organ bath in response to acetylcholine. The heparin-treated group exhibited a significant improvement in acetylcholine-induced relaxation (27%) versus both LMWH-treated (14%, P = .035) and untreated groups (11%, P = .004), although relaxation was only 50% of that observed in the uninjured control vessels (52%, P = .001). The neoendothelium formed in the heparin-treated group exhibited a more normal histological appearance and was aligned with the direction of blood flow as compared with that observed in the untreated or LMWH-treated groups.

CONCLUSIONS

These results demonstrate that in vivo heparin administration enhanced the recovery of EDRF generation and augmented normalization of the morphologic appearance of the neoendothelium.

Thoracic spinal stenosis associated with renal osteodystrophy. Diagnosis based on magnetic resonance imaging and computed tomography

We describe a case of thoracic myelopathy in a patient with renal osteodystrophy. The patient had chronic renal failure for longer than 20 years and had skeletal changes indicative of renal osteodystrophy, before the onset of myelopathy. Association between spinal stenosis and this entity has been documented only once before in the lumbar region. This is therefore the first case of thoracic myelopathy due to severe stenosis in just one vertebra in a patient with renal osteodystrophy, which was documented by computed tomography as well as magnetic resonance imaging and proven by histopathology.

Expression and cellular localization of retinol-binding protein messenger ribonucleic acid in bovine blastocysts and extraembryonic membranes

A cDNA clone encoding retinol-binding protein (RBP) was isolated from a bovine conceptus cDNA library by use of an antiserum specific for bovine conceptus RBP (bcRBP). The RBP cDNA clone, designated bcRBP-700, is 732 bp in length and codes for a protein whose predicted amino acid sequence is identical to that of bovine plasma RBP. The size of the RBP mRNA transcript in bovine chorioallantois was approximately 1.4 kb as determined by Northern blot analysis. Expression of the protein and its mRNA in expanding bovine conceptuses (Day 13) and extraembryonic membranes (Day 45) was determined by immunocytochemistry with anti-bcRBP serum and in situ hybridization with 35S-labeled bcRBP-700 cDNA. Strong immunostaining for RBP and hybridization signals for RBP mRNA were observed in trophectoderm of tubular but not spherical Day 13 blastocysts. RBP mRNA was localized in epithelial cells lining the chorion, allantois, and amnion at Day 45 of pregnancy. In addition, RBP mRNA was detected in cotyledons, the sites of chorionic attachment to the uterine endometrium and physiological exchange between the embryo and its mother. Expression of RBP in expanding conceptuses, developing extraembryonic membranes, and sites of fetal-maternal attachment suggests that the extraembryonic membranes regulate retinol transport and availability within the conceptus.

Lumbar disc herniation. Standard approach

This article describes precisely the standard surgical approach for the treatment of lumbar disc herniations. Each step in the procedure is presented in detail including anesthesia, positioning, surgical technique, and results. A brief introductory history of surgery for the ruptured intervertebral disc is also included.

Differential recovery of prostacyclin and endothelium-derived relaxing factor after vascular injury

Differential recovery of prostacyclin and endothelium-derived relaxing factor after vascular injury. Am. J. Physiol. 262 (Heart Circ. Physiol. 31): H1449-H1457, 1992. The recovery of prostacyclin (prostaglandin I2, PGI2) synthesis and endothelium-derived relaxing factor (EDRF) activity, as demonstrated by acetylcholine (ACh)-induced relaxation, by rabbit aorta was examined up to 8 wk after balloon catheter-induced injury. Following injury, basal 6-keto-PGF1 alpha formation was decreased acutely; however, after 3 wk it was not different from control. Arachidonic acid-stimulated 6-keto-PGF1 alpha formation was decreased, returning to control levels at 3 and 8 wk for thoracic and abdominal aorta, respectively. ACh-induced relaxation did not return to control levels over the 8-wk study. Initiation of reendothelialization with a layer of hyperplastic endothelial cells overlying subendothelial fibrosis and intimal hyperplasia were present at 2-3 wk. Intimal hyperplasia appeared 2 wk after injury and progressed throughout the period of the study. These data indicate that following balloon catheter-induced injury the formation of both PGI2 and EDRF is reduced and that recovery follows a differential time course. In addition, the recovery of PGI2 formation did not coincide with the attenuation of intimal hyperplasia, whereas the relationship between EDRF formation and intimal hyperplasia is uncertain.

Increased prostacyclin and thromboxane A2 formation in human varicose veins

Increased urinary metabolites of the antiaggregatory vasodilator prostacyclin (PGI2) and the proaggregatory vasoconstrictor thromboxane A2 (TXA2) have been reported in deep vein thrombosis; however, the tissue(s) of origin is uncertain. Because little is known about the formation of PGI2 or TXA2 from its common precursor, prostaglandin (PG) endoperoxide H2 (PGH2), by varicose veins, we determined the formation of 6-keto-PGF1 alpha (the stable metabolite of PGI2), TXB2 (the stable metabolite of TXA2), and PGE2. Segments of normal saphenous vein and varicose vein (nine and six patients, respectively) were incubated with 10 microM [14C]PGH2 for 2 min at 37 degrees C; products were separated by thin-layer chromatography. Surface area and mass of normal and varicose vascular segments were 19.5 +/- 0.8 versus 18.8 +/- 0.6 mm2 and 11.6 +/- 1.4 versus 10.7 +/- 0.7 mg, respectively. Formation of 6-keto-PGF1 alpha and TXB2 by the segments of varicose vein was significantly increased over that of normal vein: 157 +/- 14 versus 243 +/- 17 pmole of 6-keto-PGF1 alpha (P less than 0.005) and 22 +/- 3 versus 35 +/- 5 pmole of TXB2 (P less than 0.01). The formation of PGE2 by segments of varicose vein was not significantly different from that of normal vein (201 +/- 9 vs 219 +/- 11, respectively). Deoxyribonucleic acid (DNA) content of normal and varicose vein was 1.69 +/- 0.12 and 1.51 +/- 0.13 mg per gram of tissue, respectively. The data suggest that the increased PGI2 formation may reflect increased activity or content of PGI2 synthase. The increase in TXA2 formation may reflect increased productivity or an increased presence of residual platelets or microemboli.

Induction of transcription factor AP-1 by adenovirus E1A protein and cAMP

Treatment of adenovirus-infected mouse S49 cells with cAMP analogs leads to the transcriptional induction of early viral genes. E1A proteins and cAMP work in synergy to activate several of these genes. We now demonstrate that the transcription factor AP-1 is modestly induced by cAMP in S49 cells and induced to significantly higher levels by cAMP in the presence of E1A proteins. Cytoplasmic levels of c-fos and junB mRNAs are rapidly increased by cAMP, and the induction is substantially stronger in the presence of E1A protein. The AP-1 activity binds efficiently to both AP-1 and activating transcription factor (ATF)/cAMP response element binding protein (CREB)-binding sites present in E1A-inducible promoters and presumably plays a role in the transcriptional activation of adenovirus genes by E1A proteins and cAMP.

Molecular diversity in the abdominal aortic aneurysm phenotype

Abnormalities of collagenous peptides were detected among a group of 20 patients with abdominal aortic aneurysms, studied by high-performance liquid chromatography/NaDodSO4-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) analysis of the cyanogen bromide (CB) cleavage products of insoluble skin protein. Three abnormal patterns were identified as follows: (1) relative deficiency of a peptide with a relative molecular mass of approximately 58 kilodaltons (four patients); (2) relative decrease in the ratio of alpha-2 to alpha-1 (I) CB peptides (seven patients); and (3) decreased detection of all collagenous CB and pepsin cleavage products (one patient, who was also heterozygous for the Z allele of alpha 1-antitrypsin). The "minimal hypothesis" to explain these findings is that most of the observed abnormalities can be explained by collagenolysis in vitro, although a mutation in the primary structure of collagen has not been ruled out in all patients. Molecular heterogeneity appears to occur within the aneurysm phenotype, and the findings in the patient in group 3 allow identification of one possible risk factor in abdominal aortic aneurysmal disease that has a genomic assignment.

Cell proliferation and expression of the transferrin receptor gene: promoter sequence homologies and protein interactions

A 365-bp fragment from the 5' region of the human transferrin receptor gene has been subcloned and sequenced. This fragment contains 115 bp of flanking sequence, the first exon, and a portion of the first intron. It contains a TATA box, several GC-rich regions, and is able to efficiently promote expression of the bacterial CAT gene in mouse 3T3 cells. Sequence comparisons demonstrate that this DNA segment has homology to the promoter regions of the human dihydrofolate reductase gene and the mouse interleukin 3 gene, as well as to a monkey DNA sequence that has homology to the SV40 origin and promotes expression of an unidentified gene product. Several high molecular mass proteins that interact with the transferrin receptor gene promoter have been identified. The activity of these proteins is transiently increased in 3T3 cells that have been stimulated by serum addition. This increase precedes a rise in transferrin receptor mRNA levels in the cytoplasm, which in turn precedes entry of the cells into S phase. DNase I footprinting of the transferrin receptor promoter reveals several protein binding sites. Two of the sites are within the conserved GC-rich region of the promoter. One of these binding sites probably interacts with Spl, while the second interacts with an uncharacterized protein.

Leghemoglobin-like sequences in the DNA of four actinorhizal plants

A cloned cDNA partial copy of a soybean leghemoglobin mRNA was used to probe genomic DNA of four species of actinorhizal plants. Southern blot hybridization revealed the presence of sequences with homology to the leghemoglobin probe in DNA from Alnus glutinosa, Casuarina glauca, Ceanothus americanus and Elaeagnus pungens. The hybridization patterns of the restriction fragments revealed some fragment size conservation between the DNA of soybean and the DNA of four actinorhizal plants which are taxonomically unrelated to soybean or to each other. The results presented here indicate that globin gene sequences are much more widely distributed in the plant kingdom than has previously been thought. Furthermore, if sequence conservation is actually as high as the restriction fragment patterns suggest, the evolution of the DNA surrounding the globin sequences has been highly constrained.

Use of a protein-blotting procedure and a specific DNA probe to identify nuclear proteins that recognize the promoter region of the transferrin receptor gene

We describe a procedure for detecting high-affinity, sequence-specific DNA-binding proteins from crude nuclear extracts. The technique utilizes electrophoretic transfer of NaDodSO4/PAGE-fractionated proteins onto nitrocellulose filters. Incubation of the filters with a 5% (wt/vol) solution of nonfat dry milk effectively blocks nonspecific and low-affinity DNA-binding sites. Incubation of the blocked filters with radiolabeled DNA under optimal binding conditions and subsequent autoradiography reveals high-affinity DNA-protein interactions. We have used this procedure to identify proteins that bind specifically to the promoter region of the transferrin receptor gene.

Cerebellopontine angle gumma

A rare lesion, a gumma in the cerebellopontine angle, is reported. Gumma may mimic other more commonly occurring cerebellopontine angle tumors. The computed tomographic (CT) appearance and histological characteristics are discussed. The literature of cerebral gumma is reviewed. This is the only reported case of cerebellopontine angle gumma seen on CT scan and verified histologically at operation.

A sequence related to 4.5 S RNA and the B1 family of repeated DNA in the 5' flanking region of the mouse beta-globin gene

A beta-globin gene probe containing 5' flanking DNA hybridizes to a small nuclear RNA from Friend erythroleukemia cells, which was subsequently identified as 4.5 S RNA. This hybridization is shown to reflect complementarity between the Alu consensus region of 4.5 S RNA and the DNA sequence between nucleotides -33 and -48 from the beta-globin gene transcription initiation site.

Femoral neuropathy and retroperitoneal hemorrhage

A case of femoral neuropathy secondary to psoas muscle hematoma in a patient on warfarin sodium anticoagulation therapy is presented. Computed tomography was used to establish the diagnosis. The literature is reviewed with regard to the pathophysiology, clinical presentation, and therapy of this case. Surgical decompression is suggested to shorten the recovery period and minimize residual neurological deficit.

Theory into hospital practice: a pilot implementation

Implementing the Adaptation Model required that the model's concepts be explicitly identified, defined, and understood. Guidelines, standards and tools had to be revised or developed. Effective nursing administration leadership and the personal and professional commitment of administrators, educators, and staff nurses to the goal were necessary ingredients. The abstract nature of theory often requires sheer determination and hard thinking if it is to be effectively applied to practice. A formal education process must also be dynamic and ongoing. Project members continue to gain greater insight into the model's structure, identify problems in its application, and seek ways to solve them. Their combined, concentrated efforts have proved a cost-effective way to close gap between education and practice. The project's initial outcomes, increased patient satisfaction and expanded professional nursing, support the application of the Adaptation Model in our hospital. Further validation of its structure and the value of its outcomes, however, needs additional study, and extended application in multiple practice settings. Validation of the Roy Adaptation Model or any of the evolving conceptual frameworks for nursing practice requires use, input, and evaluation by nurses in all settings. Opening the theoretical domain to hospital nurses needs the support and leadership of nursing and hospital administrators.

Ribosomal RNA sequence conservation and gene number in the larval brine shrimp

The haploid genome size of Artemia is determined to be about 0.9 X 10(12), as evidenced both by Feulgen microspectrophotometry of individual diploid class nuclei, which are but one of five polyploid classes present within the larvae, and by analysis of the reassociation kinetics of the isolated single copy DNA component. Polysomes isolated from 24-h incubation stage larvae contain an average of 10 ribosomes per messenger RNA molecule. Their rRNAs are found to have sedimentation coefficients of 18 S and 26 S, corresponding to molecular weights of 0.70 X 10(6) and 1.40 X 10(6), respectively, as determined by polyacrylamide electrophoresis and also by sucrose density centrifugation. Denaturation in glyoxal followed by agarose gel electrophoresis shows that unlike deuterostome rRNAs, Artemia 26 S rRNA contains a cryptic nick about midway in the molecule, which is not found in the 18 S molecule. Isolated rRNAs were labelled in vitro with 125I and hybridized with filter-immobilized DNA to saturation, which occurred at 0.051% for Xenopus, and at 0.074% for Artemia. From these results, it is calculated that in the haploid Artemia genome there are about 320 copies of the (18 S + 26 S) ribosomal RNA genes. Reciprocal heterologous hybridizations between these two species show that they share about 30% homology between their rDNA coding sequences.

Thrombosed vein of Galen aneurysm

The authors report a case of thrombosed vein of Galen aneurysm in a 4.5-year-old girl with craniofacial dysostosis (Crouzon's disease). Six previously reported cases appear in the literature. The initial presentation is often associated with the symptoms and signs of hydrocephalus. Computed tomography shows an enhancing mass in the region of the posterior 3rd ventricle with the characteristic "target sign." Arteriography of all aspects of both the anterior and the posterior cerebral circulation is essential. Surgical results in cases of vein of Galen aneurysm have generally been poor, but recent reports of successful operative intervention to treat the thrombosed variety promise satisfactory treatment.

The iron and subunit binding sites of hemerythrin. The role of histidine, tyrosine and tryptophan

Of the three tyrosine residues available for nitration by tetranitromethane in hemerythrin, nitration of tyrosine residue 70 has no effect on dissociation of octomers to monomers, but nitration of tyrosines 18 and/or 67 results in dissociation to monomers. The latter data suggests these residues are important for subunit association. The reactive sulfhydryl, the modification of which produces dissociation, was protected as a mixed disulfide during the nitration but was regenerated for analysis of the state of association. Residue 70 can be selectively modified because of its exposed position and perhaps because of its slightly lower pk of 6.9, compared to 7.3 as an average of all nitrotyrosines in a completely nitrated hemerythrin. Solvent perturbation studies in 20% Me2SO indicate that 3 tyrosines, in agreement with the nitration results, and 2 tryptophan residues are exposed; however, oxidation at a 2-fold molar excess of N-bromosuccinimide oxidizes three tryptophan whereas a 3.5-fold excess oxidizes all four, but results in a rapid active site destruction. Photo-oxidation with methylene blue results in oxidation of only two tryptophan residues. These data have been interpreted to indicate that two tryptophans are free and two are involved in subunit association. Photo-oxidation with methylene blue results in the destruction of three histidines but no decrease in active site absorption. Histidine modification with diethyloxydiformate shows that three histidines react with no change in active site absorption. These results indicate that four histidines are unreactive toward these modifying agents and are therefore either buried or are ligands to the iron.