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Williams-Campbell syndrome is a rare disorder characterized by a deficiency of cartilage in subsegmental bronchi leading to distal airway collapse and bronchiectasis. We report the first case of lung transplantation in a patient with end-stage lung disease secondary to Williams-Campbell syndrome. Although the patient did not have proximal airway collapse prior to transplantation, his posttransplant course was complicated by the development of bronchomalacia of the right and left mainstem bronchi. The patient experienced recurrent pulmonary infections and died of bacterial pneumonia 1 year after transplantation. Autopsy revealed cartilage deficiency in both right and left mainstem bronchi. A hypothesis may be made that a combination of proximal cartilage deficiency and posttransplant airway ischemia led to the development of bronchomalacia after lung transplantation. Thus, in contrast to previous reports, the cartilage deficiency in Williams-Campbell syndrome can involve both proximal and distal airways. Consequently, bilateral sequential lung transplantation may not be an effective therapeutic option in patients with this syndrome.

Lung transplantation is a viable therapy for patients with a variety of end-stage lung diseases. Our active program now includes over 200 lung transplant operations with acceptable one- and 3-year survival rates of 78% and 61%. A major focus of clinical research at this institution is to design strategies to prevent the development of chronic allograft dysfunction. Our preliminary work in this regard has been encouraging. In addition, a major research focus has been to design protocols to prevent the development of posttransplant infections. Our work with aerosolized ABLC represents a major advance at our center, and additional randomized prospective studies are ongoing to define the optimal antifungal prophylaxis after transplantation. Ongoing clinical and basic research at Duke and elsewhere should continue to advance the field of clinical transplantation and ultimately lead to more acceptable long-term outcomes for lung allograft recipients.

Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension associated with fibrotic occlusion of the smaller pulmonary veins. Although vasodilator therapy is effective in many patients with primary pulmonary hypertension, the role of vasodilators in PVOD is unclear because of concerns about precipitating pulmonary edema. Recently, however, there have been reports of successful therapy with oral vasodilators or intravenous administration of prostacyclin in patients with PVOD. In contrast, a patient with PVOD is described who developed acute pulmonary edema and respiratory failure during low-dose prostacyclin infusion, leading to death. This report suggests that vasodilators, especially prostacyclin, must be used with extreme caution in patients with known PVOD.

Background: Infection with Nocardia species is an increasingly recognized complication of solid organ transplantation. Nocardia asteroides accounts for most transplant-related nocardiosis, while Nocardia brasiliensis rarely causes infection in organ transplant recipients., Methods: We describe a case of disseminated infection with N brasiliensis in a single-lung transplant recipient who also had concomitant infections with viral and fungal organisms., Results: Although the mortality rate is high in immunocompromised patients with disseminated Nocardia infection, our patient responded favorably to prolonged antimicrobial therapy., Conclusions: This case illustrates that N brasiliensis, like N asteroides, produces pulmonary disease and dissemination in solid organ transplant recipients, and demonstrates the utility of prolonged treatment with trimethoprim-sulfamethoxazole in Nocardia infections.

The activity of piperacillin/tazobactam, ampicillin/sulbactam, imipenem and nafcillin alone and in combination with vancomycin was compared with vancomycin monotherapy against MRSA in test-tube time-kill studies and in infected fibrin clots. Bactericidal activity was achieved with all regimens except nafcillin monotherapy in test tubes but only with imipenem/vancomycin and nafcillin/vancomycin in fibrin clots infected with heterogeneous strains. No regimen was effective against the homogeneous strain. These agents may have potential as alternatives to vancomycin in selected infections.

Vancomycin-resistant enterococci (VRE) are a major problem in numerous institutions in the United States. Most VRE are resistant to all available antimicrobial agents, resulting in serious therapeutic dilemmas. The resistance genes are transmitted on transposons, so the potential for dissemination to other species is significant. Risk factors associated with VRE infection and colonization are vancomycin and cephalosporin use, but numerous patient-related factors also contribute. Although resistant strains appear to arise from the patient's endogenous flora, VRE may be spread through direct contact with contaminated environmental surfaces and hands of caregivers. Published guidelines for preventing such spread suggest implementing infection-control practices and vancomycin restrictions. The ideal drug regimen for the treatment of VRE is unknown. Various drug combinations have been studied in the laboratory, but patient treatment data are scarce. There is an urgent need for new antimicrobial agents.

We compared the pharmacodynamic activities of levofloxacin versus vancomycin, with or without rifampin, in an in vitro model with infected platelet-fibrin clots simulating vegetations. Infected platelet-fibrin clots were prepared with human cryoprecipitate, human platelets, calcium, thrombin, and approximately 10(9) CFU of organisms (MSSA 1199 and MRSA 494) per g and then were suspended via monofilament line into the in vitro model containing Mueller-Hinton growth medium. Antibiotics were administered by bolus injection into the model to simulate human pharmacokinetics; the regimens simulated included levofloxacin at dosages of 800 mg every 24 h (q24h) and 400 mg q12h, vancomycin at 1 g q12h, and rifampin at 600 mg q24h. Each model was run in duplicate over a 72-h period. Infected platelet-fibrin clots were removed in duplicate from each model, weighed, homogenized, serially diluted with sterile 0.9% saline, and plated on tryptic soy agar plates and plates containing antibiotics at 3, 6, and 12 times the MIC to evaluate the emergence of resistance. Time-kill curves were constructed by plotting the inoculum size versus time. Residual inoculum at 72 h was used to compare regimens. All levofloxacin regimens were significantly better than vancomycin monotherapy against both isolates (P < 0.002). Against MSSA 1199, levofloxacin q24h was significantly better than all other regimens, including levofloxacin q12h (P < 0.002); however, no difference between the levofloxacin monotherapy and combination therapy (with rifampin) regimens against MRSA 494 was seen. Killing activity for levofloxacin appeared to correlate better with the peak/MIC ratio than with the area under the curve/MIC ratio. The addition of rifampin significantly enhanced the activity of vancomycin but had little effect upon the activity of levofloxacin. For MRSA 494, vancomycin plus rifampin resulted in the greatest killing (P < 0.05). Development of resistance was not detected with any regimen. Levofloxacin may be a useful therapeutic alternative in the treatment of staphylococcal endocarditis, and further study with animal models of endocarditis or clinical trials are warranted.

Ten patients were treated with conventional dosing (CD) and continuous-infusion (CI) vancomycin therapy in this prospective, randomized, crossover study. Patients were randomized to receive either CD or CI therapy for 2 consecutive days and then crossed over to receive the opposite regimen for 2 days. CD therapy consisted of 1 g of vancomycin every 12 h. CI therapy consisted of a 500-mg loading dose followed by 2 g infused over 24 h. Ten serum samples were obtained on the second day of each therapy for pharmacokinetic and pharmacodynamic analyses. Two clinical isolates of Staphylococcus aureus, one methicillin sensitive (MSSA 1199) and one methicillin resistant (MRSA 494), were chosen for pharmacodynamic evaluation of both regimens. The patient demographics (means +/- standard deviations [SD]) were as follows: sex, six males, four females; age, 36 +/- 11 years; and serum creatinine, 0.72 +/- 0.18 mg/dl. Mean pharmacokinetic parameters +/- SD for CD therapy were as follows: elimination rate constant, 0.16 +/- 0.07 h-1; half-life, 5.6 +/- 3.5 h; volume of distribution, 33.7 +/- 25 liters, 0.5 +/- 0.2 liters/kg; maximum concentration in serum, 53.4 +/- 19.3 micrograms/ml; and minimum concentration, 8.4 +/- 5.9 micrograms/ml. The steady-state concentration for CI was 20.2 +/- 11.1 micrograms/ml. Overall, both regimens resulted in the MIC being exceeded 100% of the time. The mean CD trough serum bactericidal titer (SBT) was 1:8, and the average CI SBTs were 1:16 for both isolates. Even though there was no statistically significant difference between CD trough and CI SBTs, the CI SBTs remained > 1:8 for 100% of the time versus 60% of the time for CD therapy. During CI therapy, 20 and 40% of the patients maintained SBTs of > 1:32 throughout the dosing interval for MSSA 1199 and MRSA 494, respectively. During CD therapy, however, only 10% of patients maintained SBTs of > 1:32 during the entire dosing interval for both isolates. The mean areas under the bactericidal titer-time curve (AUBC24s) +/- SD for MSSA 1199 were 528 +/- 263 for CD therapy and 547 +/- 390 for CI therapy. The mean AUBC24s +/- SD against MRSA 494 were 531 +/- 247 for CD and 548 +/- 293 for CI therapy. Similar to the AUBC24, the mean area under the concentration-time curve for a 24-h dosing interval divided by the MIC (AUC/MIC24) ratios +/- SD were 550.0 +/- 265.7 for CD and 552.6 +/- 373.4 for CI therapy, respectively. No statistically significant differences were found between any of the pharmacodynamic parameters for CD and CI therapy. In addition, no adverse effects with either CD or CI therapy were observed during the study. We conclude that CI and CD vancomycin therapy demonstrated equivalent pharmacodynamic activities. Although CI therapy was more likely to result in SBTs that remained above 1:8 for the entire regimen, the clinical impact of this result is unknown. Serum drug concentration variability was observed with both treatment regimens but to a lesser extent with CI administration. CI administration of vancomycin should be further evaluated to determine the clinical utility of this method of administration.

The Cobas Integra from Roche Diagnostic Systems is a new clinical laboratory analyzer with continuous and random-access features for routine chemistries, specific proteins, electrolytes, hormones, therapeutic drugs, and drugs of abuse. The system maintains 68 test-specific reagent cassettes on board, along with multiple ion-selective electrodes (ISEs) for electrolyte determinations. This gives the Cobas Integra the capability of analyzing as many as 72 analytes without having to load additional reagents. We describe the basic analyzer configuration and the subsystems for absorbance, fluorescence polarization, and ISE measurements. Performance characteristics for precision, methods comparison, and on-board stability are given for assays representative of the various test groups. The 29 Cobas Integra tests evaluated in the present study show good agreement (r > or = 0.98 and slopes generally 0.90 to 1.12) with the respective methods available on either the Olympus AU5000, Hitachi 911 or 717, Behring BNA, or Abbott TDx systems. Total assay precision (CV) ranged from 0.8% to 8.5%, and calibration curves were stable for as long as 20 weeks. Test throughput, which is dependent on pipetting sequence, was determined to be up to 600 tests per hour without ISE and up to 750 tests per hour with ISE; the time to first result was 2.0-10.0 min.

Chromosome locations of non-major histocompatibility complex (MHC) genes contributing to insulin-dependent diabetes mellitus (IDDM) in mice have been determined by outcrossing NOD mice to other inbred strains congenic for the NOD MHC haplotype (H2g7). At least nine non-MHC IDDM susceptibility genes (Idd) were previously identified at first backcross (BC1) after outcross of NOD to C57BL/10.H2g7 congenic mice (B10.H2g7). We investigated whether the same set of Idd loci segregated with IDDM susceptibility after outcross of NOD to NON.H2g7 congenic mice. Since the outcrosses to NON.H2g7 and B10.H2g7 were performed in the same vivarium, direct comparisons were made of the chromosomal locations and relative strengths of Idd alleles in diabetic progeny from the two different outcrosses. In comparison with the NOD x B10.H2g7 outcross, the NOD x NON.H2g7 outcross produced significantly higher IDDM frequencies in F1, F2, and BC1 generations. The high F2 diabetes frequency allowed evaluation of the effects of homozygous expression of both the susceptibility and the resistance allele at Idd loci. This analysis demonstrated that no single non-MHC Idd locus was essential for the onset of diabetes in this cross. After outcross to NON.H2g7, Idd4 (chromosome [Chr] 11), Idd5 (Chr 1), and Idd8 (Chr 14) did not segregate with IDDM in either the BC1 or the F2 generation. Diabetogenic NOD-derived alleles at Idd2 (Chr 9), Idd3 (Chr 3), and Idd10 (Chr 3) were segregating in the BC1. An NON-derived allele contributing to susceptibility on Chr 7 (Idd7) was also detected. Dominant traits, detectable only in the F2 cross, were encoded by Chr 4 (Idd9) and two newly mapped loci on Chr 13 (Idd14) and 5 (Idd15). A third dominant trait was encoded by Chr 6 (possibly Idd6), but here, in contrast to Idd9, Idd14, and Idd15, the NON allele was diabetogenic. Stepwise logistic regression analysis of the BC1 and F2 data confirmed that the ability to identify certainty of the non-MHC Idd loci was contingent on the extent of homozygosity for NOD background genes. This study shows that the diabetogenic phenotype can be achieved through the actions of variable combinations of MHC-unlinked genes and a diabetogenic MHC haplotype.

Cefepime (CP) is a new injectable cephalosporin with a broad spectrum of activity and stability against common chromosomally and plasmid-mediated beta-lactamases. The bactericidal activities of CP, ceftazidime (CZ), cefotaxime (CTX), and ceftriaxone (CAX) against reference and clinical strains of Staphylococcus aureus, an isogenic pair of Enterobacter aerogenes strains (wild type and a CZ-resistant derepressed mutant), and a Klebsiella pneumoniae isolate possessing a TEM-10 beta-lactamase were investigated in a two-compartment pharmacodynamic in vitro infection model which simulates human pharmacokinetics. An inoculum of approximately 10(6) CFU/ml was used in all model experiments. Antibiotics were administered to simulate the following regimens: CP at 2 g every 12 h (q12h), CZ at 2 g q8h, CTX at 2 g q8h, and CAX at 2 g q24h. Human albumin was added during experiments with CAX and staphylococci to simulate protein binding. Samples were removed at multiple time points over a 48-h period to determine the inoculum size for time-kill curves. Development of resistance was detected by inoculating samples obtained at 0, 24, and 48 h onto antibiotic-containing agar plates. The time to 99.9% killing was used to compare drug regimens. Against staphylococci, the time to bacterial eradication was significantly delayed with CAX-albumin. All regimens had similar activities against the wild-type Enterobacter strain; however, regrowth was noted with CZ, CTX, and CAX against the CZ-resistant strain. There were no differences between the CP, CTX, and CAX regimens against K. pneumoniae. Of interest, no regrowth of any organism was noted with CP. These data indicate that CP has activity against S.aureus and CZ-resistant gram-negative bacilli.

We compared the pharmacodynamics and killing activity of ceftazidime, administered by continuous infusion and intermittent bolus, against Pseudomonas aeruginosa ATCC 27853 and ceftazidime-resistant P. aeruginosa 27853CR with and without a single daily dose of amikacin in an in vitro infection model over a 48-h period. Resistance to ceftazidime was selected for by serial passage of P. aeruginosa onto agar containing increasing concentrations of ceftazidime. Human pharmacokinetics and dosages were simulated as follows: half-life, 2 h; intermittent-bolus ceftazidime, 2 g every 8 h (q8h) and q12h; continuous infusion, 2-g loading dose and maintenance infusions of 5, 10, and 20 micrograms/ml; amikacin, 15 mg/kg q24h. There was no significant difference in time to 99.9% killing between any of the monotherapy regimens or between any combination regimen against ceftazidime-susceptible P. aeruginosa. Continuous infusions of 10 and 20 micrograms/ml killed as effectively as an intermittent bolus of 2 g q12h and q8h, respectively. Continuous infusion of 20 micrograms/ml and an intermittent bolus of 2 g q8h were the only regimens which prevented organism regrowth at 48 h, while a continuous infusion of 5 micrograms/ml resulted in the most regrowth. All of the combination regimens exhibited a synergistic response, with rapid killing of ceftazidime-susceptible P. aeruginosa and no regrowth. Against ceftazidime-resistant P. aeruginosa, none of the ceftazidime monotherapy regimens achieved 99.9% killing. The combination regimens exhibited the same rapid killing of the resistant strain as occurred with the susceptible strain; however, regrowth occurred with all regimens. The combination regimens of continuous infusion of 20 micrograms/ml plus amikacin and intermittent bolus q8h or q12h plus amikacin continued to be synergistic. Overall, continuous infusion monotherapy with ceftazidime at concentrations 4 to 5 and 10 to 15 times the MIC was as effective as an intermittent bolus of 2 g q12h (10 to 15 times the MIC) and q8h (25 to 35 times the MIC), respectively, against ceftazidime-susceptible P. aeruginosa. Combination therapy with amikacin plus ceftazidime, either intermittently q8h or by continuous infusion of 20 micrograms/ml, appeared to be effective and exhibited synergism against ceftazidime-resistant P. aeruginosa.

Constitutional nonreciprocal translocations are extremely rare, and even their existence is controversial. We report on a newborn infant with a de novo nonreciprocal translocation between chromosomes 1 and 8 resulting in 1q42.3 deletion syndrome. Fluorescent in situ hybridization with whole chromosome paints confirmed the conventional cytogenetic diagnosis.

We have searched the human genome for genes that predispose to type 1 (insulin-dependent) diabetes mellitus using semi-automated fluorescence-based technology and linkage analysis. In addition to IDDM1 (in the major histocompatibility complex on chromosome 6p21) and IDDM2 (in the insulin gene region on chromosome 11p15), eighteen different chromosome regions showed some positive evidence of linkage to disease. Linkages to chromosomes 11q (IDDM4) and 6q (IDDM5) were confirmed by replication, and chromosome 18 may encode a fifth disease locus. There are probably no genes with large effects aside from IDDM1. Therefore polygenic inheritance is indicated, with a major locus at the major histocompatibility complex.

To facilitate large-scale genetic mapping of the human genome, we have developed chromosome-specific sets of microsatellite marker loci suitable for use with a fluorescence-based automated DNA fragment analyser. We present 254 dinucleotide repeat marker loci (80% from the Généthon genetic linkage map) arranged into 39 sets, covering all 22 autosomes and the X chromosome. The average distance between adjacent markers is 13 centiMorgans, and less than 4% of the genome lies more than 20 cM from the nearest marker. Each set of microsatellites consists of up to nine marker loci, with allele size ranges that do not overlap. We selected marker loci on the basis of their reliability in the polymerase chain reaction, polymorphism content, map position and the accuracy with which alleles can be scored automatically by the Genotyper program.

Partial exclusion mapping of the nonobese (NOD) diabetic mouse genome has shown linkage of diabetes to at least five different chromosomes. We have now excluded almost all of the genome for the presence of susceptibility genes with fully recessive effects and have obtained evidence of linkage of ten distinct loci to diabetes or the prediabetic lesion, insulitis, indicative of a polygenic mode of inheritance. The relative importance of these loci and their interactions have been assessed using a new application of multiple polychotomous regression methods. A candidate disease gene, interleukin-2 (Il-2), which is closely linked to insulitis and diabetes, is shown to have a different sequence in NOD, including an insertion and a deletion of tandem repeat sequences which encode amino acid repeats in the mature protein.

Immunization of normal mice with bacterial DNA elicits a significant IgG anti-DNA response and has been explored as a model of systemic lupus erythematosus. To determine whether this induced response is influenced by sex, we have measured anti-DNA levels in normal male and female BALB/c mice immunized with single stranded DNA from E. coli as complexes with methylated bovine serum albumin (mBSA) in adjuvant. By ELISA assays, anti-DNA levels of immunized females were approximately 16-fold higher than those of immunized males; levels of antibodies to the mBSA carrier were similar, however. The antibodies from females and males showed a similar degree of cross-reactivity when assayed using other natural and synthetic DNA antigens, including mammalian DNA. These findings suggest the potentiation of anti-DNA production in females by antigen-specific mechanisms and provide further evidence that immunization with bacterial DNA replicates features of autoantibody production in SLE.

We report on an infant girl born with findings of CHARGE association who proved to be a genetic male (46,XY) on cytogenetic study. Further investigation of the genitalia demonstrated partially female internal organs but absence of gonads by ultrasonography, hormone studies, and absence of ZFY by DNA probe of Yp. Pelvic exploration confirmed lack of gonadal tissue and uterus. Facial phenotype was compatible with CHARGE appearance.

To evaluate the effects of streptozocin on maternal pancreatic beta-cell function, we administered the agent to 14 pregnant ewes at 85 to 90 days' gestation on two occasions, 4 days apart. Intravenous glucose tolerance tests were performed before the initial administration, before the second dose, and 4 weeks after the final dose of streptozocin. There was a significant elevation in maternal fasting blood glucose (82 +/- 8.1 mg/dl before streptozocin and 102.6 +/- 6.8 mg/dl after streptozocin, p less than 0.05). Five late-gestation ewes were used as controls, and a significant elevation in fasting plasma glucose levels was found in the streptozocin-treated animals (71.4 +/- 7.1 mg/dl control vs 102.6 +/- 6.8 mg/dl after streptozocin, p less than 0.05). The glucose tolerance test curves showed a significant elevation 4 weeks after streptozocin compared with before streptozocin (p less than 0.05). The maternal insulin response to streptozocin demonstrated a loss of the second-phase insulin response to the glucose load after one dose of streptozocin and loss of the first phase after two doses. The fetuses of the streptozocin-treated ewes showed a significant elevation in plasma glucose level compared with that of controls (13.3 +/- 0.8 mg/dl, n = 5) vs 42.1 +/- 8.1 mg/dl, n = 10; p less than 0.05, control vs streptozocin, respectively). There was a consistent trend to fetal hyperinsulinemia in the fetuses of the streptozocin-treated ewes, although this did not achieve statistical significance (3.3 +/- 0.8 microIU/ml, n = 5 vs 9.6 +/- 2.5 microIU/ml, n = 10; p = 0.06, control vs streptozocin, respectively). The fetal insulin/glucose ratio was preserved in the streptozocin-treated ewes. Comparison of fetal weights between the control and diabetic ewes showed a significant increase in fetal weight in the fetuses of diabetic ewes (3280 +/- 46 gm in control fetuses vs 3710 +/- 54 gm in diabetic fetuses, p less than 0.05). The alterations in the maternal glucose and insulin response resulting from streptozocin-induced pancreatic beta-cell destruction combined with elevations in fetal glucose, insulin, and weight provides a large animal model suitable for investigation of gestational diabetes in pregnancy.

Delayed organ maturation is a characteristic of the fetus of the diabetic mother with poor glucose control. We hypothesized that the ovine fetal catecholamine maturation sequence would be delayed in the fetus of the diabetic ewe. Twelve pregnant ewes were rendered glucose intolerant by the administration of streptozocin at 85 to 95 days' gestation. Maternal diabetic status was verified with fasting blood glucose assessments. The fetal metabolic clearance rate of epinephrine was determined at 126 to 140 days' gestation by the constant infusion of 0.1 micrograms epinephrine per kilogram estimated fetal weight per minute. Fetal arterial blood gas values, lactate, glucose, and insulin levels were measured before infusion; after 20, 30, and 40 minutes of epinephrine infusion; and 15, 30, and 60 minutes after cessation of infusion. Fetal plasma glucose rose significantly from a control level of 42.1 +/- 8.2 to 64.6 +/- 5.9 mg/dl during the epinephrine infusion (p less than 0.05). Fetal insulin levels increased from a baseline of 9.2 +/- 2.6 microIU/ml to 32.4 +/- 18.0 in the recovery period (p less than 0.05), and lactate levels similarly rose from 36.4 +/- 4.8 to 52.2 +/- 8.2 mg/dl (p less than 0.05). The plasma epinephrine production rates did not vary significantly between fetuses less than 135 and greater than 135 days' gestation (15.4 +/- 1.5 vs 13.9 +/- 2.0 ng/min, p greater than 0.5). The fetal metabolic clearance rate of epinephrine at early gestations (less than 135 days) was similar to that of the fetus of the nondiabetic ewe (35.3 +/- 3.4 vs 28.0 +/- 4.3 ml/min/kg, p greater than 0.2). However, at later gestations (greater than 135 days) the fetus of the diabetic ewe did not have the increase in the metabolic clearance rate previously published for the control fetus (32.0 +/- 4.6 vs 133.7 +/- 41.7 ml/min/kg, p less than 0.05). These data appear to indicate an absence in the maturation of the metabolic clearance rate of epinephrine in the fetus of the diabetic ewe. The observed alteration in the metabolic clearance rate of epinephrine of the fetus of the diabetic ewe could potentially impair the response to stress.

We report the effect of high glucose infusion on vascular resistance in isolated human placental cotyledons perfused with Krebs-Ringer-bicarbonate solution containing 80 mg/dl (4.4 mmol/L), 160 mg/dl (8.8 mmol/L), or 320 mg/dl (17.6 mmol/L) D-glucose (n = 6). Placental vascular resistance remained constant during 25-minute perfusion periods with 80 mg/dl followed by 160 mg/dl glucose solution. Subsequent perfusion with 320 mg/dl glucose produced a significant increase in placental vascular resistance. Placentas were also studied in which the placental cotyledon was sequentially perfused for 25-minute periods with solutions containing glucose at 80 mg/dl followed immediately by 320 mg/dl (n = 5). Placental vascular resistance remained constant throughout perfusion with 80 mg/dl glucose solution but increased significantly after beginning perfusion with 320 mg/dl glucose. We conclude that the increase in placental vascular resistance appears to be a function of the high glucose level rather than the duration of glucose perfusion.

We hypothesized that streptozocin-induced ovine diabetes would cause alterations in the placental production of thromboxane and prostacyclin. With a tissue incubation technique, we examined the placental production of thromboxane and prostacyclin in cotyledons from seven normal near-term ewes (127 +/- 3 days' gestation) and six streptozocin-induced diabetic ewes (125 +/- 3 days' gestation). Diabetic status was verified with serial fasting blood glucose assessments. Placental tissue was incubated in Dulbecco's modified Eagle's medium for 48 hours at 37 degrees C with 95% oxygen and 5% carbon dioxide. Samples were collected at 0, 1, 2, 4, 8, 20, 32, and 48 hours. Radioimmunoassay of the stable metabolites thromboxane B2 and 6-keto-prostaglandin F1 alpha were used to determine thromboxane and prostacyclin production, respectively. Placental thromboxane production was reduced in diabetic animals when compared with control animals (5.63 +/- 2.81 vs 7.32 +/- 1.37 pg/mg per hour, respectively; p less than 0.05). Prostacyclin production was also significantly reduced in the diabetic placentas compared with control placentas (11.44 +/- 4.06 vs 16.29 +/- 4.59 pg/mg per hour, respectively; p less than 0.05). We conclude that the ovine placenta produces thromboxane and prostacyclin. The ovine thromboxane production rate is comparable to that of the human placenta but the prostacyclin production rate is approximately two to three times higher. The observed decrease in the placental production of thromboxane and prostacyclin may reflect an adverse effect of hyperglycemia directly on eicosanoid production or indirectly through decreased placental cellular proliferation.

A study was made of the effects of maternal exercise on fetal plasma concentrations of catecholamines in nine ewes with chronically catheterized singleton fetuses at 125 to 137 days' gestation. The ewes were subjected to acute treadmill exercise of 2.5 mph for 45 minutes with continuous recording of maternal and fetal blood pressures. Samples of arterial blood were obtained for measurement of catecholamines, glucose, and blood gases. Changes in blood flow in fetal organs in response to maternal exercise were assessed by injection of radioactive microspheres. The maternal plasma catecholamine responses were related to the severity of the exercise stress as indicated by the index of cardiac effort. The fetal responses did not correlate with maternal cardiac effort. A significant decrease in fetal Po2 with a moderate alkalosis occurred, accompanied by a significant elevation in circulating levels of norepinephrine. At the peak of exercise, there was an increase in fetal renal, adrenal, and placental blood flows, as compared to the control period.

During a one-year period, 838 nonstress tests, 425 nipple stimulation contraction stress tests (NS-CSTs), and 115 spontaneous CSTs were done. Results were compared to those of NSTs and CSTs done by classic methods during a previous one-year period. The results revealed no hyperstimulation from contraction stress testing with nipple stimulation, and a significant reduction in the time to perform both tests conducted simultaneously when compared to the nonstress test plus classic oxytocin challenge test. The time to perform the combined tests compared to the routine nonstress test was not significantly different. Moreover, a cost-saving was also demonstrated. The combination of the NST and nipple stimulation CST appeared to be safe, efficacious, and cost-effective.

Arginine vasopressin (AVP) metabolic clearance rates (MCR) and production rates (PR) were measured in chronically catheterized fetuses, maternal ewes (130-135 days of gestation), and 1- to 6-month-old sheep using constant infusion noncompartmental kinetic methodology. No significant differences in mean basal plasma AVP levels, MCR rates or PR were found among the fetuses, maternal ewes or lambs. MCR of AVP did not change with steady-state plasma AVP levels varying from 2 to 68 micronmicron/ml. Neither the placenta nor the fetal kidney appear to play a significant role in AVP metabolic clearance.

An adenylate cyclase highly responsive to stimulation by parathyroid hormone (PTH) and calcitonin (CT) in vitro was observed at certain times during normal prenatal development of the maxillary-palatal process complex in the golden hamster. Responses of the enzyme to these hormones were barely detectible at the earliest stage examined (day 10/20). The enzyme became extremely sensitive to activation by either hormone during the time of rapid growth of the palatal processes (day 11/20) and during fusion between the palatal processes (day 12/20). Thereafter, responses were greatly diminished and little or no activation of adenylate cyclase was observed until birth. Adenylate cyclase from fetuses in which clefts of the secondary palate were induced by maternal treatment with hydrocortisone (50 mg) on day 11/3 also displayed an enhanced sensitivity to PTH and CT on day 11/20, but the sensitivity of the enzyme was greatly decreased from that in normal animals during the normal time of palatal fusion (day 12/20) and was barely detectible or absent at the remaining time periods studied (days 13/20 and 14/20). Addition of hydrocortisone to the incubation mixture, either separately or in combination with PTH or CT, did not remarkably affect the response of adenylate cyclase to these hormones. Moreover, the appearance of the adenylate cyclase sensitive to hormonal activation did not result from changes in phosphodiesterase activity during palatal maturation.

In ascorbic acid-requiring species (human, guinea pig), elevations of circulating histamine occur as the result of marginal ascorbic acid status. Marginal ascorbic acid status during pregnancy is associated with preeclampsia, abruption, and prematurity. Furthermore, circulating histamine is known to be elevated in these complications perhaps as a result of placental dysfunction which diminishes normal placental histaminase. We hypothesized that women with preeclampsia and premature labor would have elevated histamine and the lowest concentrations of ascorbic acid. Plasma total whole blood histamine and ascorbic acid were surveyed in women in term (T) and preterm (PT) labor. Blood histamine was elevated in PT compared to T labor but so was plasma ascorbate, indicating that marginal ascorbate status does not cause the elevated circulating histamine observed in PT. However, marginal ascorbate status concomitant with reduced placental histaminase may contribute to further increases in circulating histamine and to any pathology which might result from elevated histamine. Regression analysis of histamine on ascorbate for T and PT labor revealed a significant inverse relationship between ascorbate and histamine only in PT labor (p less than 0.027). An unexpected finding was that a history of maternal cigarette smoking, to a degree which resulted in marginal ascorbic acid status, confounded the relationship between ascorbate and circulating histamine in T labor.

The present study was initiated to determine whether specific hormones would influence adenylate cyclase activity within the maxillary-palatal complex during formation of the hamster secondary palate. Stages from initial appearance of the palatal processes to shortly after birth were studied. Highest basal adenylate cyclase activities occurred during the earliest periods of palate development. This basal enzyme activity began to diminish as palatal fusion occurred and remained lowered until birth. Activation of adenylate cyclase by fluoride was maximal at concentrations of 5-10 mM, and was observed throughout the span of palatal development. Fluoride activation of adenylate cyclase was greatest prior to fusion of the palatal processes, then decreased until birth when a slightly increased enzymatic stimulation was seen. Norepinephrine and epinphrine were the catecholamines most capable of inducing increased activation of adenylate cyclase at most periods of palatal growth. Increased enzyme activity in the presence of norepinephrine was more susceptible to antagonism by the beta adrenergic agent, propranolol, than to the alpha adrenergic agent, phentolamine. The remaining catecholamines, namely isoproterenol and dopamine, displayed a lesser ability to activate the enzyme, and adenylate cyclase was not equally responsive to these catecholamines at identical developmental stages. Other hormones, i.e. histamine, serotonin, thyrotropin, growth hormone, thyroxine and glucagon were generally ineffective in activating the enzyme. Phosphodiesterase activity was not detected until shortly before birth.

Fifty-five ewes with chronically catheterized singleton gestations were studied to assess changes in basal concentrations of fetal catecholamines with increasing gestational age. All pregnancies were time dated, and measurements of catecholamines were conducted at least 5 days after placement of fetal catheters when fetal metabolic parameters had normalized. Plasma concentrations of catecholamines were measured by radioenzymatic assay. Additionally, fetal heart rate (FHR) and corrected mean blood pressure were analyzed in 32 of the fetuses for correlation with plasma levels of catecholamines. Multiple regression analysis revealed significant inverse correlations of fetal plasma concentrations of catecholamines with gestational age, as follows: norepinephrine (p less than 0.001), epinephrine (p less than 0.05), and dopamine (p less than 0.01). FHR correlated inversely with gestational age (p less than 0.001) and positively with circulating levels of norepinephrine (p less than 0.001).

We studied the permeability of the ovine placenta to AVP. 125I-AVP (9.3 +/- 1.9 mU) with approximately 82 (+/- 17.3) X 10(6) counts per 5 min were infused intravenously in 6 pregnant ewes. Six blood samples were collected at 10-min intervals over a 1-hour period from chronically catheterized maternal and fetal sheep. 125I-AVP in maternal and fetal plasma samples (1 ml each) were counted in a gammacounter for 5 min. Maternal counts decreased from 9,300 to 2,500 counts per 5 min over the hour following infusion but no increase in radioactivity could be measured in fetal blood, indicating that the sheep placenta is impermeable to 125I-AVP.

After the infusion of 500 ml 20% mannitol to 12 pregnant ewes, we studied fetal plasma osmolality responses in chronically catheterized fetal lambs at 129-140 days' gestation. To compare the effects of arginine vasotocin (AVT) alone and AVT plus cortisol on fetal/maternal water transfer, the mannitol infusion was repeated during a 2-h fetal infusion of AVT alone (7 microU/kg/min) and during infusion of AVT with cortisol (50 micrograms/h) (eight and six animals, respectively). The fetal osmolar response to maternal mannitol administration was compared to the response following the baseline mannitol study in the same sheep. In four of the ewes, an identical (sham) study was performed substituting 500 ml normal saline for the mannitol infusion to the ewe. Fetal AVT infusion significantly obtunded the fetal osmolality increment induced by maternal mannitol alone [P less than 0.001, analysis of variance (ANOVA)]. Fetal AVT administered concurrently with cortisol produced an increment in fetal plasma osmolality in response to maternal mannitol that was significantly enhanced compared with that during fetal AVT infusion alone (P less than 0.001, ANOVA). The response to AVT with cortisol was similar to that following mannitol alone. Normal saline (sham protocol) produced no change in maternal or fetal osmolality. These results indicate that fetal AVT inhibits fetal to maternal water transfer following an osmotic stimulus to the ewe, while cortisol (infused with AVT) tends to counteract the inhibitory effect of AVT on fetal/maternal water transfer.

Fourteen patients with severe pregnancy-induced hypertension and low lecithin/sphingomyelin (L/S) ratios were treated with 5 mg of dexamethasone phosphate intramuscularly every 12 hours for four doses to induce fetal pulmonary maturity. A comparison was made of the average gestational age, mean L/S ratio, method of delivery, Apgar scores, mean birth weight, and incidence of respiratory distress syndrome in these patients and in 16 patients with similar demographic backgrounds and clinical presentations who did not receive corticosteroid therapy. There was no significant difference between the two groups except that the time of treatment (or nontreatment) to delivery was longer in the steroid group. There were two cases of neonatal respiratory distress syndrome in the treatment group, and one of these infants died. In the control group, there were two neonatal deaths among four cases of respiratory distress syndrome. There was no clinical evidence of intraventricular hemorrhage in any neonate nor was there aggravation of hypertension in the parturient patients. The administration of corticosteroids to induce fetal pulmonary maturity in patients with severe pregnancy-induced hypertension who are carefully selected and monitored does not appear to be contraindicated.

The regional localization of hormonally sensitive adenylate cyclase within the maxillary-palatal process complex was examined in tissue homogenates at different stages during the development of the secondary palate in the golden hamster. The most potent agents capable of activating adenylate cyclase were parathyroid hormone (PTH) and calcitonin (CT). Highest activities were observed in the intact maxillary process-palatal shelf complex and the isolated maxillary process prior to and during fusion of the palate. Thereafter, neither hormone displayed a remarkable capacity to elevate enzyme activity. Parathyroid hormone and CT exhibited a similar, but considerably reduced, capacity for enzyme stimulation in the isolated palatal shelf. 1'-Norepinephrine also increased adenylate cyclase activity in both the palatal shelf and the maxillary process at the earlier stages. Prostaglandins (PG) E1, E2, and F2 alpha stimulated adenylate cyclase activity within the intact palate, the maxillary process, and the palatal shelf primarily at the earlier stages. The adenylate cyclase from the isolated palatal shelf was more sensitive to stimulation by the PGs than that from either the intact palate samples or isolated maxillary processes. The findings imply that the fusion process of the secondary palate is under a highly sensitive hormonal control mechanism.

Three membrane-associated proteolytic activities in Escherichia coli were resolved by DEAE-cellulose chromatography from detergent extracts of the total envelope fraction. On the basis of substrate specificity for the hydrolysis of chromogenic amino acid ester substrates, the first two eluting activities were determined previously to be protease V and protease IV, respectively (M. Pacaud, J. Bacteriol. 149:6-14, 1982). The third proteolytic activity eluting from the DEAE-cellulose column was further purified by affinity chromatography on benzamidine-Sepharose 6B. We termed this enzyme protease VI. Protease VI did not hydrolyze any of the chromogenic substrates used in the detection of protease IV and protease V. However, all three enzymes generated acid-soluble fragments from a mixture of E. coli membrane proteins which were biosynthetically labeled with radioactive amino acids. The activity of protease VI was sensitive to serine protease inhibitors. Using [3H]diisopropylfluorophosphate as an active-site labeling reagent, we determined that protease VI has an apparent molecular weight of 43,000 in polyacrylamide gels. All three membrane-associated serine proteases were insensitive to inhibition by Ecotin, and endogenous, periplasmic inhibitor of trypsin.

A mild dermatitis probably due to Cheyletiella yasguri was observed in 2 persons whose pet dog was infested with this parasite. Cheyletiella mites differ morphologically from sarcoptic mites, which cause canine and human scabies. Treatment of man and dog with 1% gamma benzene hexachloride is usually successful in clearing this condition.

A woman presented with severe exfoliative dermatitis and a pelvic mass subsequently found to be fallopian tube carcinoma. After resection of the tumor and four courses of cisplatin, doxorubicin, and cyclophosphamide, the skin condition cleared.

The acardiac anomaly is a rare condition found only in monozygotic multiple pregnancies, usually twins. We present a review of the pathophysiology of acardia and a case report. Twin embryonic membrane formation is discussed, since a conceptual understanding of the subject is necessary for the early recognition of this and other severe anomalies. Emphasis is placed on close sonographic monitoring to insure the best chance of survival of the normal twin, who may die of heart failure if delivery is not properly timed.

The effect of hypoxemia on arginine vasopressin (AVP) and oxytocin (OT) release was investigated in the chronically catheterized fetus and ewe. During 30 min of 10% maternal oxygen delivery, mean (+/- SEM) arterial PO2 decreased from 105 +/- 10.6 to 48 +/- 3.5 mm Hg in the ewe and from 21 +/- 1.3 to 12 +/- 0.8 mm Hg in the fetus (each P less than 0.001). Arterial PCO2 decreased from 35 +/- 4.4 to 29 +/- 1.0 mm Hg in the ewe, whereas fetal PCO2 decreased from 43 +/- 2.3 to 35 +/- 3.5 mm Hg (P less than 0.05). Blood pH increased from 7.44 +/- 0.03 to 7.56 +/- 0.04 in the ewe (P less than 0.01) and from 7.36 +/- 0.004 to 7.40 +/- 0.006 in the fetuses (P less than 0.01). Baseline mean AVP levels were identical in ewes and fetuses (0.7 +/- 0.1 microU/ml). After 30 min of hypoxia, plasma AVP levels remained unchanged in the ewes (0.9 +/- 0.1), but increased dramatically in the fetuses (47 +/- 21 microU/ml) (P less than 0.001). There was a highly significant correlation between the duration of hypoxia and log fetal AVP concentrations (r = 0.85). The log fetal plasma AVP also was inversely correlated to the log fetal PO2 values (r = 0.83). Mean baseline fetal and maternal plasma OT levels were 2.6 +/- 0.5 microU/ml and 2.2 +/- 0.5 microU/ml, respectively. After 30 min of hypoxia fetal and maternal OT values were 2.9 +/- 0.8 microU/ml (not significant).