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The antimicrobial agents nalidixic acid and novobiocin, both inhibitors of DNA gyrase, preferentially inhibit the growth of DNA repair-deficient Escherichia coli, Salmonella typhimurium and Bacillus subtilis. On the other hand, these agents exhibit no demonstrable mutagenicity for S. typhimurium and E. coli even when tested under conditions designed to take the metabolic properties of these agents into consideration. Novobiocin and nalidixic acid are widely used in animal and human medicine and further studies to assess their genetic and carcinogenic potentials appear to be in order.

The effect of modifiers of liver mixed function oxidase activity on the in vitro alpha-hydroxylation and mutagenicity of N-nitrosopyrrolidine (NPYR) has been examined in rats and hamsters. Hamster post-mitochondrial supernatants were able to convert NPYR to a mutagen more efficiently than rat preparations under all conditions studied. Aroclor 1254 pretreatment caused the greatest increase in mutagenic activity in both species while phenobarbital and 3-methylcholanthrene pretreatment gave intermediate values when compared to uninduced preparations. Microsomal alpha-hydroxylation of NPYR was induced by Aroclor 1254 pretreatment in both species. Pretreatment with 3-methylcholanthrene increased alpha-hydroxylation in hamsters but decreased it in rats. Phenobarbital pretreatment only slightly increased microsomal alpha-hydroxylation in either species. When microsomal alpha-hydroxylation rates were expressed per gram wet weight of liver, better agreement between rates of alpha-hydroxylation and mutagenicity in phenobarbital pretreated animals was obtained since inducer associated changes in total microsomal protein content were taken into account. An example of differential induction of an activation pathway (alpha-hydroxylation) and a degradative pathway (aldehyde dehydrogenase) is presented to illustrate a potential source of error in the interpretation of metabolic data obtained from post-microsomal supernatants and whole animal studies.

Fifty-two hypertensive patients whose blood pressure (BP) was controlled on two medications received either 16 sessions of thermal biofeedback (n = 30) for hand warming or 8 sessions of progressive muscle relaxation (n = 22) prior to medication withdrawal. A number of biochemical measures, including plasma norepinephrine (NEPI) (supine and standing), plasma renin activity, plasma aldosterone, and urinary sodium and potassium, were taken before treatment and after treatment while medication remained constant. Results for the biofeedback-treated patients showed significant reductions in mean arterial pressure as well as in both supine and standing NEPI, while the other biochemical measures were unchanged. There were no significant changes on any variable for the relaxation-treated patients. Although the group data support a reduction in peripheral sympathetic tone as associated with the decrease in BP for the thermal biofeedback condition, dose-response relations were not significant.

The value of short-term microbial assay procedures to screen for environmental agents possessing carcinogenic and/or genetic activity has been established, as evidenced by the plethora of recently published studies and critical reviews on this subject (1–14). Among the available tests, the Salmonella mutagenicity assay developed by Ames arid his associates has achieved prominence, especially as its reliability as a predictor of carcinogenicity has been demonstrated in a number of studies (1, 7–9). Indeed, a number of investigators have suggested a quantitative relationship between mutagenic potency and carcinogenic potential (15,16; however see also 18–20).

Fifty-nine recipients received renal allografts from an HL-A haploidentical family member. Immunogenicity of the incompatible haplotype was measured by skin grafts exchanged within each family when possible, and renal allograft recipients were assigned prospectively to two groups depending on the skin graft survival time (Group 2A greater than 15 days; Group 2B less than 15 days). If skin grafts could not be accomplished, the patients were place in an unclassified group, Group 2. Renal function at one and 2 years following engraftment did not differ between the two groups. Mixed lymphocyte stimulation of recipient lymphocytes by mitomycin-treated donor lymphocytes also was comparable in the groups. Histopathological evaluation by light, immunofluorescence, and electron microscopy at least 6 months following allografting did not distinguish between the groups. The only differentiating characteristic was that Group 2A patients did not experience their primary rejection episode until an average of 18 days following transplantation, whereas Groups 2B and unclassified 2 had their initial primary rejection episode at average days 9 and 5, respectively. In our clinical program, matching for HL-A halotypes continues to be the best predictor for long-term renal function in consanguineous renal transplantation.

From a series of 470 specimens of renal tissue examined by immunofluorescence microscopy, 20 specimens were identified and studied in detail from patients without evidence of systemic disease in which IgA was the predominant localizing immunoglobulin. All patients presented with hematuria which was recurrent or persistent, often being exacerbated by upper respiratory infection. Most of the group pursued a benign clinical course with little evidence of decline in renal function. Histopathologic changes in renal biopsy specimens of most of the group consisted of a proliferative glomerulonephritis of variable intensity. Characteristic alterations were seen by electron microscopy which included the presence of electron-dense deposits within the mesangium, the hilar regions of the glomerulus and the basement membrane of Bowman's capsule. Evidence for activation of complement by the alternate pathway at C3 was found with properdin localization in 14 of 15 specimens and with the absence of detectable Clq and C4 in 15 specimens studied for these early acting components. It is concluded that the combined clinical, morphologic and immunologic findings warrant consideration of IgA nephropathy as a distinct clinicopathologic entity.

Organic solvent extracts from airplane emission particulates are mutagenic for Salmonella typhimurium strain TA98. Using Salmonella tester strains deficient in enzymes required for the bioactivation of various nitroarenes, the mutagenicity present in these emissions was ascribed to the presence of nitrated polycyclic aromatic hydrocarbons. Based on the known aircraft particulate emission rates at U.S. airports, and using 1-nitropyrene (1-NP) and 1,8-dinitropyrene (1,8-DNP) as surrogates, it is calculated that at a minimum 7 kg 1-NP and 20 g, 1,8-DNP are emitted daily at a typical U.S. airport.

Nitropyrenes as well as several other nitroarenes and their metabolites exhibit considerable mutagenicity for Salmonella tester strains (TA102 and TA96) which have adenine-thymine base pairs at the mutational target. This finding is unexpected as previous biochemical studies had shown that arylation at the C8 position of DNA-guanine is the only chemically and biologically significant reaction. This conclusion is supported by the extraordinary mutagenic potency of these chemicals in Salmonella strains with guanine at the mutational site (e.g., TA98). The present results indicate that a minor reaction with DNA-adenine may result in the formation of an unusually potent promutagenic DNA adduct.

Characterization of a Salmonellatyphmurium mutant strain (TA98/1,8-DNP6) resistant to the mutagenicity of nitrated polycyclic aromatic hydrocarbons (nitroarenes) revealed that it was also non-responsive to the mutagenic action of nitroso- and N-hydroxylaminoarenes. The mutant strain was fully sensitive to the mutagenic action of the corresponding hydroxamic acid ester. These results suggest that TA98/1,8-DNP6 is deficient in a specific esterifying enzyme and that esterification of the penultimate mutagenic metabolites of nitro- and aminoarenes (e.g., arylhydroxylamines) to form potent electrophiles is controlled by a specific gene.

The trabecular meshwork of eyes with open-angle glaucoma has been demonstrated to have an increase in gamma globulin and plasma cells, raising the question of an immunogenic mechanism in this disorder. In the present study, however, immunofluorescence assays on the trabecular meshwork of eyes with open-angle glaucoma were negative for specific immunoglobulins and for complement components that would result specifically from an antigen-antibody reaction. The study fails to provide any evidence in support of an immunogenic mechanism in open-angle glaucoma.

Strains derived from Salmonella typhimurium LT-2, which are used as tester strains in mutagenicity assays, show significant changes in biochemical phenotypes. The presence of plasmid pKM101 in these strains greatly increases both the frequency of these shifts as well as the spectrum of phenotypes involved. It is suggested that in plasmid-free strains these variations reflect the effects of endogeneously induced mutatons which are amplified in the absence of a functional uvrB gene product. In plasmid-containing strains this genetic drift may be promoted further by the pKM101-coded error-prone DNA repair system. The observation of a plasmid-mediated genetic drift lends support to the suggestion that transposons may contribute to the carcinogenic process.

Reaction potential maps (RPM's) around the constituent bases of DNA have been plotted using the CNDO/2 method. The maps were drawn to evaluate site selectivity in electrophilic attack on the bases of DNA as a function of two considerations: base sequence and the nature of the attacking reagent. It was found that base sequence does have a substantial effect on a site's reactivity and that a change in the nature of the attacking reagent can alter site selectivity of the electrophile. The former result was applied in a specific case to offer a plausible explanation for some results of a recent study of the mutagenic effects of arylating metabolites of nitrofluorenes in the Salmonella tester strains TA98 and TA97. These strains differ in the arrangement of guanine and cytosine residues at the mutational target ("hot spot"). The results also suggest that the "hot spot" for TA98, which consists of a run of alternating guanine and cytosine base pairs, does not exist in the Z-configuration.

Abnormalities of the heart are a frequent and possibly ubiquitous problem in patients with Friedreich's ataxia, but their pathogenesis is unclear. Postmortem findings are reported from the hearts of three patients with Friedreich's ataxia who died of congestive heart failure and atrial arrhythmias. Particular attention was paid to the following: the large and small coronary arteries, the nerves and ganglia, the conduction system, and the histological and cellular features of the cardiomyopathy. There were pleomorphic nuclei and focal fibrosis and degeneration throughout each heart including the conduction system. There were distinctive abnormalities of both large and small coronary arteries, and focal degeneration of nerves and ganglia. These observations suggest a mosaic concept for the pathogenesis for the cardiomyopathy of Friedreich's ataxia that involves the interplay of molecular faults, cardiomyopathy, cardioneuropathy, and coronary disease.

The design and analysis of the fast wave antenna to be used for ICRF heating experiments on the Alcator C‐Mod tokamak are described. A movable single‐strap low‐field‐side‐launch loop antenna will be used during the initial operation period. Structural analysis against disruption and thermal analysis are performed. Optimized two‐strap antennae with twice the surface area are planned for high‐power heating experiments. Antenna‐plasma coupling studies indicate a poor (

In a retrospective clinicopathological study, 48 kidney biopsy specimens from 16 children (mean age, 7 years) and 17 adults (mean age, 33 years) with histological evidence of focal glomerular sclerosis (FGS) were examined using light, immunofluorescence and electron microscopy. The histopathological findings were related to the clinical course of each patient. At the clinical onset of the disease, the nephrotic syndrome was seen more commonly in children (12/16) than adults (7/17), while the incidence of both hypertension (children 1/16 versus adults, 9/17) and renal insufficiency (children, 0/16 versus adults, 7/17) was greater in adults. Despite a shorter average follow-up, (adults 3 10/12 years versus children, 7 years), the incidence of hypertension (adults, 13/17 versus children, 7/16) and renal functional impairment (adults, 13/17 versus children, 3/16) remained greater in the adult patients. One child and three adults died in renal failure while two adults underwent transplantation and on requires regular dialysis therapy. Nine of 15 pediatric patients treated with corticosteroids experienced partial or complete remission in either their nephrotic syndrome or level of urine protein excretion, while just 3 of 6 adult patients treated with corticosteroids experienced a partial remission, but never became protein-free. There was an excellent correlation in all patients between the degree of functional renal impairment and the extent of glomerular and nonglomerular histopathological damage in the kidney. It is concluded that in the adults, FGS represents a more severe and progressive disease process and is less responsive to therapy.

Allyl chloride (3-chloroprene) is mutagenic for Salmonella typhimurium and it induces gene conversions in Saccharomyces cerevisiae. It also displays DNA-modifying activity for E. coli. This is in contrast to a recent study which reported its lack of genetic activity for Salmonella typhimurium.

A patient suffering baclofen overdose successfully treated with atropine is reported. Three hours after admission for ingestion of at least 300 mg baclofen as a single dose, the patient became comatose and subsequently bradycardic, hypotensive, and hypothermic. A prompt increase in heart rate and blood pressure followed administration of 1 mg of atropine sulfate. Atropine appears to be useful in treating cases of baclofen overdose complicated by bradycardia and hypotension.

Two infants with the hemolytic uremic syndrome are presented. Immunofluorescences studies were done on renal biopsies of each patient as well as on autopsy tissue of one of the patients who subsequently died. In contrast to previously reported immunofluorescence studies in HUS in which only fibrinogen localization was observed, intense localization of antihuman IgM and β 1 C globulin were observed in glomeruli and in renal arterioles. Similar localization of antihuman IgM, β 1 C globulin, and fibrinogen was observed in dermal vessels of one of the infants. (Reasons for the discrepancy of these positive findings with those reported by others are discussed.) The present observations suggest that at least in some cases the pathogenesis of HUS may involve humoral immune mechanisms rather than a nonimmune Shwartzman type of coagulopathy.

The environmental contaminants pyrene, 1-nitropyrene, 1,8-dinitropyrene, fluoranthene, and 3-nitrofluoranthene were exposed to light (greater than or equal to 310 nm) either in DMSO, or following coating onto silica. Under all conditions tested the pyrenyl were less stable than the fluoranthenyl compounds. During irradiation in DMSO or on silica, 1-nitropyrene had half-lives of 1.2 and 6 days, while those of 3-nitrofluoranthene were 12.5 and greater than 20 days, respectively. The photodecomposition of 1,8-dinitropyrene resembled that of 1-nitropyrene with half-lives of 0.7 and 5.7 days. A principle photodecomposition product of 1,8-dinitropyrene was identified as 1-nitropyren-8-ol. It was also found that when the nitroarenes were exposed to light, the loss of compound was associated with a concomitant loss of mutagenicity in Salmonella typhimurium strain TA98. The mechanism of nitrated polycyclic aromatic hydrocarbon decomposition and 1-nitropyren-8-ol formation, and the relevance to the atmospheric disposition of these compounds are discussed.

Two mutagenic metabolites of phenacetin, p -nitrosophenetol and N -hydroxy- p -phenetidine, were tested in S. typhimurium strains TA100, its nitroreductase-deficient derivative TA100NR, and O -acetylase-deficient strains TA100 Tn5-1-8-DNP1011 and -DNP1012 in the presence or absence of an exogenous metabolic activation system. The results indicate that bacterial nitroreductase(s) and O -acetylase(s), shown to be involved in the conversion of certain nitroarenes, are not required for the intrabacterial activation of the two phenacetin metabolites to bacterial mutagens. In view of the low reactivity of nitrosoarenes towards nucleophiles at neutrality, the mechanism by which they exert such a high mutagenic effect in S. typhimurium strains remains to be clarified, but is discussed.

Silver sulfadiazine was found to be devoid of mutagenic potential in a sensitive mutagenicity assay using Salmonella typhimurium. In view of the close relationship between mutagenicity in this system and carcinogenicity in animals, these findings suggest that silver sulfadiazine is apparently also devoid of carcinogenic properties.

The Salmonella/microsome test developed by Ames and his coworkers has been widely used in the evaluation of chemicals for genotoxic potential. Although the value of this assay is well recognized, there have been no comprehensive studies on the interlaboratory reproducibility of the method using a standardized protocol. A program was therefore initiated to compare the results obtained in four laboratories from testing a series of coded mutagens and nonmutagens using a standardized protocol. Additional objectives of this study were to compare male Fisher 344 rat, B6C3F1 mouse, and Syrian hamster liver S-9 preparations for the activation of chemicals; to compare Aroclor 1254-induced liver S-9 from all three species with the corresponding non-induced liver S-9's; and to compare the response of Escherichia coli WP-2 uvrA with the Salmonella typhimurium tester strains recommended by Ames. Since a primary use of in vitro microbial mutagenesis tests is the identification of potential carcinogens by their mutagenicity, the authors decided to compare the animal species and strains used by the National Cancer Institute/National Toxicology Program (NCI/NTP) for animal carcinogenicity studies.

Immunologic studies were performed on 11 renal specimens from seven patients with progressive systemic sclerosis (PSS). Two patients had the chronic renal lesions of PSS and five had acute PSS renal disease. One of the latter patients underwent renal transplantation after developing acute renal failure with recurrence of lesions in the allograft. The lesions in the allograft were morphologically indistinguishable from the renal lesions of acute PSS. Immunofluorescence microscopy revealed vascular localization of IgM along with early and late acting complement components C1Q, C4, and C3 in all specimens including the allograft. Fibrinogen localization was observed in the vasculature of patients with the acute form of the disease. Antiglobulin, detected by fluorescein-labeled, heat-aggregated gamma-globulin, was also present in vascular lesions from two of the specimens; Eluates of four of the kidneys including the allograft contained antinuclear antibodies. In addition, antiglobulin activity was present in eluates from three of the four kidneys, The findings suggest that (1) renal vascular lesions in PSS may result from injury via immune complexes composed of nuclear antigens and antibody, (2) the predominance of IgM in the vascular lesions may reflect the presence of rheumatoid factor in the immune complexes, and (3) a similar pathogenetic mechanism may have resulted in allograft failure following renal transplantation of a patient with PSS.

The mutagenicities of a series of nitroarenes and related electrophilic metabolites of aromatic amines were studied in Salmonella typhimurium strains TA98 and TA97, which have, respectively, (GCGC/CGCG)2 and (CCC/GGG)2 as their mutational sites. For electrophiles, primarily bicyclic species, that form adducts with nucleophilic sites other than the C8 of guanine (G), the ratios of activities in the two strains is near unity. On the other hand, for electrophiles consisting of cyclic structures with more than two rings and that are reported to react solely with the C8 of G, the ratio of activities (TA98/TA97) is in excess of 1.6. Quantum mechanical calculations indicate that (1) in the plane of G, the N7, N3, and 06 of G are more likely nucleophilic targets than C8 and (2) adduct formation at the C8 of G requires electrophilic attack from above or below the plane of G. It is hypothesized that because of steric hindrances, nitroarenes and derivatives containing in excess of two rings cannot react with the preferred nucleophilic sites and, therefore, form adducts with the more accessible C8. However, such an out-of-the-plane attack is influenced by the nature of the nearest neighbor, as evidenced by the difference in mutagenic responses of TA98 and TA97, alternating GCs being preferred over other combinations. Further quantum mechanical calculations indicate that the nature of the nearest neighbor does indeed affect the nucleophilicity of the C8 of G but that the expression of this effect is apparently masked by the overriding steric effects.

Medical science now dictates more precise and more physiological treatment of disorders in the circulation and myocardium. One of the major limitations of conventional catheters, laser catheters, angioscopes and other flexible micro-instrumentation is that their distal ends are not functionally maneuverable. Catheter Research, Inc. has developed an angulation mechanism using shape memory alloys to manipulate the distal tip of a catheter, fiber optic bundle, or other flexible micro-instrumentation. This technology features the following: 1. Controlled angulation of the tip 2. Precise tip placement 3. Miniature size 4. Advancement of a catheter, angioscope, or fiber optics bundle without a guide wire 5. Center lumen of catheters which are free of any obstructions and adaptable for use of fiber optics or micro-instrumentation

Bones from a stratified sedimentary deposit in the Puu Naio Cave site on Maui, Hawaiian Islands, reveal the late Holocene extinction of 19 species of birds. The age of the sediment and associated fauna was determined by direct radiocarbon dating (tandem particle accelerator-mass spectrometer; TAMS) of amino acids extracted from bones weighing as little as 450 mg. The 14C dates indicate that sediment has been accumulating in the lava tube for at least the last 7750 years, a suitable time frame for testing the hypothesis that Holocene extinction on islands began after human colonization. Despite growing evidence that a worldwide wave of extinctions coincided with human colonization of oceanic islands, little radiometric data have been available to date the extinction of most small fossil vertebrates on islands. The TAMS technique of dating purified collagen from the bones of small vertebrates could lead to vastly improved chronologies of extinction for oceanic islands where catastrophic mid- to late-Holocene extinction is expected or known to have occurred. Chronologies derived from nonarcheological sites that show continuous sedimentation, such as the Puu Naio Cave deposit, may also yield key evidence on the timing of earliest human settlement of Oceania.

We compared a clinic-based regimen of 16 individual sessions (2 per week) of thermal biofeedback with a largely home-based regimen of 5 sessions (spread over 8 weeks) for the treatment of essential hypertension in patients who required at least two drugs to maintain control of blood pressure (BP). On the basis of the clinical end point of being successfully withdrawn from the second stage medication while BP remained under control, the clinic-based regimen (5 of 9) was superior (chi less than (1) = 4.0, p less than .05) to the home-based regimen (1 of 9). Internal analyses point to more frequently obtaining a hand temperature of at least 95 degrees F by the office-based patients as possibly the reason for the difference.

Chrysene and 3-methylcholanthrene are transformed to direct-acting mutagens by photodynamically generated singlet oxygen. In view of the presence of this species of oxygen in the polluted atmosphere, the possible conversion of environmental polycyclic aromatic hydrocarbons to mutagens and to potential direct-acting (‘ultimate’) carcinogens deserves consideration.

Extracts of selected xerographic toners and copies were found to be mutagenic in the Salmonella assay. The activity was independent of the xerographic hardware and process and was traced to nitropyrenes present as impurities in the carbon black, the toner colorant. Manufacturing process changes resulted in a substantial reduction of the nitropyrene content of the carbon black and thus in the mutagenicity of the corresponding toners. Nitropyrenes are potent frameshift mutagens, and possible mechanisms for their biological action are discussed.

The effect of chronic ethanol consumption on the ability of isolated liver fractions to metabolize the carcinogen N-nitrosopyrrolidine (NPY) was examined. Microsomal fractions of treated animals exhibited increased rates of alpha-hydroxylation of NPY. Similar increases in the specific activities of aniline hydroxylase, reduced nicotinamide adenine dinucleotide phosphate cytochrome c reductase, and the specific content of cytochrome P-450 were also observed. In contrast, no differences in the specific activities of benzo(a)pyrene hydroxylase or glucose-6-phosphatase were observed. Liver postmitochondrial supernatants from ethanol-consuming animals were able to produce 5 times more mutants than did control preparations. It is concluded that alpha-hydroxylation of NPY is probably the mechanism by which NPY is converted to a mutagen and that this pathway can be induced by ethanol.

Nineteen patients with polymyalgia rheumatica and/or temporal arteritis were classified by degree of clinical and arteriographic abnormality, biopsy grade of arteriosclerosis, and giant cell arteritis (GCA). Temporal arteriograms were very sensitive in detecting abnormal arteries. However, the assumption of some previous studies, that certain angiographic abnormalities are synonymous with GCA, was not supported, since biopsies from distal sites in a Class I and a Class II arteriogram revealed only arteriosclerosis. Class III arteriograms correlated with proximal biopsies of GCA. Immunofluorescent staining was negative in all cases.

Immobilization tests were conducted on a wild-type strain of Campylobacter fetus subsp. intestinalis and on a mutant lacking an antiphagocytic cell surface component. Highly effective immobilization of the mutant, both as single cells and clumps of cells, was produced with an antiserum containing antibodies specific for the flagellar hook and filament and for the O antigen. Damage to flagellar hooks after reaction with this antiserum was observed only with cells of the mutant. Single-cell immobilization of the mutant was also produced with an antiserum specific for a heat-stable somatic antigen which was distinct from the O antigen and was exposed on the cell surface only of the mutant. Minimal immobilization of the wild strain was brought about by either of these antisera. It was shown also that O antibodies had no effect on the motility of either the wild strain or mutant. These findings indicate that antibody-mediated immobilization may be brought about by effects on the flagellar hook or cell body, as well as on the flagellar filament. Furthermore, the protection from immobilization afforded the bacterium by the antiphagocytic surface structure suggests a dual function for this virulence factor in the infected animal.

Previous studies on the mutagenicity of nitroheterocyclics and nitrated polycyclic aromatic hydrocarbons had indicted the probable existence in Salmonella typhimurium of a multiplicity of nitroreductase activities of varying specificities which are required for the expression of the mutagenicity of nitro-containing chemicals. In the present study evidence is presented that these activities reside in different gene products: (a) strains totally lacking in the nitroreductase which recognizes niridazole and related substances are not mutagenized by this group of chemicals and yet they are fully responsive to the mutagenic action of dinitropyrenes; (b) double mutants which have lost both types of specificities can be constructed. Finally, the presence of a third type of nitroreductase with a specificity for 4-nitroquinoline-1-oxide is implied by the finding that the nitroreductase-deficient strains described herein retain full sensitivity to the mutagenic action of this chemical.

It is now well recognized that short-term microbial assays, when run under carefully controlled conditions, have predictive value for the detection of the potential cancer-causing properties of most classes of chemicals. Indeed, our Laboratory has participated both in the development and validation of such assays. However, in an eagerness to obtain reliable data relating to the potential genotoxic and/or carcinogenic potentials, too much emphasis has been placed on procedural details such that sight is lost of the fact that these assays lend themselves — when suitably modified — to the elucidation of some basic biological problems. There is an increasing number of these which can be used to illustrate this point. The present report, however, deals primarily with data obtained in our own Laboratories.

The contraction stress test (CST) and nonstress test (NST) are used as fetal health assessments. Severe sickle hemoglobinopathies in the parturient have been shown to place the fetus significantly at risk. This study correlates these fetal health assessment tests with outcome data in 58 pregnancies occurring in women with sickle cell disease. There were 30 patients with homozygous sickle cell anemia (HbS-S), 19 with hemoglobin S-C disease (HbS-C), and nine with hemoglobin S-thalassemia (HbS-Thal). All received prophylactic partial exchange transfusions as part of their antepartal care. At 34 weeks' gestation, NSTs followed by CSTs were begun in each patient. A total of 255 tests were performed. Of these, 19 NSTs and 24 CSTs were unsatisfactory or questionably abnormal and were repeated. There were no nonreactive NSTs, and no patient demonstrated a positive CST. The neonatal outcome revealed one infant who was small for gestational age and two infants who were of low birth weight but appropriate for gestational age. All infants survived and were normal. These data suggest that the fetal reactivity and placental reserve among these parturients with severe sickle hemoglobinopathies were uncompromised, as these tests have been shown to be relatively sensitive assessments of fetal well-being in other maternal disorders.