Patients with resolution of low-lying placenta and placenta previa remain at increased risk of postpartum hemorrhage.

OBJECTIVE: To determine whether women who experience resolution of low placentation (low-lying placenta or placenta previa) are at increased risk of postpartum hemorrhage compared to those with normal placentation throughout pregnancy. METHODS: This was a retrospective cohort study of women who delivered at Mount Sinai Hospital between 2015 and 2019, and who were diagnosed with low-lying placenta or placenta previa on transvaginal ultrasound at the time of the second-trimester anatomical survey, with resolution of low placentation on subsequent ultrasound examination. Women undergoing second-trimester anatomical survey who had normal placentation on transvaginal ultrasound 3 days before or after the cases were randomly identified for comparison. The primary outcome was the rate of postpartum hemorrhage. Secondary outcomes included the need for a blood transfusion, use of additional uterotonic medication, the need for additional procedures to control bleeding, and maternal admission to the intensive care unit. Outcomes were assessed using a multivariable logistic regression model. RESULTS: A total of 1256 women were identified for analysis, of whom 628 had resolved low placentation and 628 had normal placentation. Women with resolved low placentation, compared to those with normal placentation throughout pregnancy, had significantly higher mean age (33.0 ± 5.4 years vs 31.9 ± 5.5 years; P < 0.01) and lower mean body mass index at delivery (27.9 ± 5.5 kg/m2 vs 30.2 ± 5.7 kg/m2 ; P < 0.01), and were more likely to have undergone in-vitro fertilization, be of non-Hispanic white race, have posterior placental location (all P < 0.01) and have private/commercial health insurance (P = 0.04). Patients with resolved low placentation vs normal placentation had greater odds of postpartum hemorrhage (adjusted odds ratio (aOR), 3.5 (95% CI, 2.0-6.0); P < 0.01), use of additional uterotonic medication (aOR, 2.2 (95% CI, 1.5-3.1); P < 0.01) and increased rates of additional procedures to control bleeding (aOR, 4.0 (95% CI, 1.3-11.9); P = 0.01). CONCLUSION: Despite high rates of resolution of low-lying placenta and placenta previa by term, women with resolved low placentation remain at increased risk of postpartum hemorrhage compared to those with normal placentation throughout pregnancy. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Eosinophil persistence in vivo and sustained viability ex vivo in response to respiratory challenge with fungal allergens.

BACKGROUND: Eosinophils are immunomodulatory leucocytes that contribute to the pathogenesis of Th2-driven asthma and allergic lung diseases. OBJECTIVE: Our goal was to identify unique properties of eosinophils recruited to the lungs and airways of mice in response to challenge with asthma-associated fungal allergens. METHODS: Mice were challenged intranasally on days 0, 3 and 6 with a filtrate of Alternaria alternata. Recruited eosinophils were enumerated in bronchoalveolar lavage fluid. Eosinophils were also isolated from lungs of mice sensitized and challenged with Aspergillus fumigatus and evaluated ex vivo in tissue culture. RESULTS: Eosinophils persist in the airways for several weeks in response to brief provocation with A. alternata in wild-type, Gm-csf- and eotaxin-1-gene-deleted mice, while eosinophils are recruited but do not persist in the absence of IL-13. Eosinophils isolated from the lungs A. alternata-challenged mice are cytokine-enriched compared to those from IL5tg mice, including 800-fold higher levels of eotaxin-1. Furthermore, eosinophils from the lungs and spleen of fungal allergen-challenged wild-type mice are capable of prolonged survival ex vivo, in contrast to eosinophils from both untreated and fungal allergen-challenged IL5tg mice, which undergo rapid demise in the absence of exogenous cytokine support. TNF-α (but not IL5, IL-3, eotaxin-1 or GM-CSF) was detected in supernatants of ex vivo eosinophil cultures from the lungs of fungal allergen-challenged wild-type mice. However, neither TNF-α gene deletion nor anti-TNF-α neutralizing antibodies had any impact sustained eosinophil survival ex vivo. CONCLUSION AND CLINICAL RELEVANCE: Eosinophils are phenotypically and functionally heterogeneous. As shown here, eosinophils from fungal allergen-challenged wild-type mice maintain a distinct cytokine profile, and, unlike eosinophils isolated from IL5tg mice, they survive ex vivo in the absence of exogenous pro-survival cytokine support. As treatments for asthma currently in development focus on limiting eosinophil viability via strategic cytokine blockade, the molecular mechanisms underlying differential survival merit further investigation.

Alternaria alternata challenge at the nasal mucosa results in eosinophilic inflammation and increased susceptibility to influenza virus infection.

BACKGROUND: Eosinophils in the nasal mucosa are an elemental feature of allergic rhinitis. OBJECTIVE: Our objective was to explore eosinophilic inflammation and its impact on respiratory virus infection at the nasal mucosa. METHODS: Inflammation in the nasal mucosae of mice was evaluated in response to repetitive stimulation with strict intranasal volumes of a filtrate of Alternaria alternata. Mice were then challenged with influenza virus. RESULTS: Repetitive stimulation with A. alternata resulted in eosinophil recruitment to the nasal passages in association with elevated levels of IL-5, IL-13 and eotaxin-1; eosinophil recruitment was diminished in eotaxin-1-/- mice, and abolished in Rag1-/- mice. A. alternata also resulted in elevated levels of nasal wash IgA in both wild-type and eosinophil-deficient ∆dblGATA mice. Interestingly, A. alternata-treated mice responded to an influenza virus infection with profound weight loss and mortality compared to mice that received diluent alone (0% vs 100% survival, ***P < .001); the lethal response was blunted when A. alternata was heat-inactivated. Minimal differences in virus titre were detected, and eosinophils present in the nasal passages at the time of virus inoculation provided no protection against the lethal sequelae. Interestingly, nasal wash fluids from mice treated with A. alternata included more neutrophils and higher levels of pro-inflammatory mediators in response to virus challenge, among these, IL-6, a biomarker for disease severity in human influenza. CONCLUSIONS AND CLINICAL RELEVANCE: Repetitive administration of A. alternata resulted in inflammation of the nasal mucosae and unanticipated morbidity and mortality in response to subsequent challenge with influenza virus. Interestingly, and in contrast to findings in the lower airways, eosinophils recruited to the nasal passages provided no protection against lethal infection. As increased susceptibility to influenza virus among individuals with rhinitis has been the subject of several clinical reports, this model may be used for further exploration of these observations.

Early atherogenesis and visceral fat in obese adolescents.

BACKGROUND/OBJECTIVES: Little information is available as to the cause of increased thickening of the intima-media of the carotid artery (cIMT) in the pediatric population. Therefore, cIMT was compared in obese adolescents and normal-weight controls, and associations between cIMT and lipid and non-lipid cardiovascular risk factors were assessed. SUBJECTS/METHODS: Subjects included 61 obese non-diabetic male and female volunteers aged 12-18 years inclusive with a body mass index (BMI) >95th percentile for age and 2-h blood glucose <200 mg dl(-1) matched to 25 normal-weight control volunteers with normal glucose levels. Each subject underwent a 2-h glucose tolerance test and measurement of hemoglobin A1c, ultrasensitive C-reactive protein, fasting insulin, blood lipids, visceral, subcutaneous abdominal and hepatic fat, and cIMT. RESULTS: Maximum cIMT was 0.647±0.075 mm in the obese subjects versus 0.579±0.027 mm in normal-weight controls (P<0.001). There was no difference in maximum cIMT between male and female subjects. There were significant correlations between maximum cIMT and BMI z-score, 2-h glucose, fasting insulin, homeostasis model assessment (HOMA), total low-density lipoprotein (LDL) cholesterol, very LDL cholesterol, high-density lipoprotein (HDL) cholesterol, HDL2 cholesterol, HDL3 cholesterol, triglycerides, remnant lipoprotein cholesterol, intermediate-density lipoprotein cholesterol, lipoprotein(a), apoprotein B100, abdominal subcutaneous fat volume, visceral fat volume and hepatic phase difference. On multiple regression analysis, visceral fat was the most significant predictor of maximum cIMT. Two-hour blood glucose, HOMA and systolic blood pressure were also significant predictors of maximum cIMT. CONCLUSIONS: cIMT was increased in the obese adolescents compared with the normal-weight-matched controls. Visceral fat was a key predictor of arterial wall thickening in these subjects. The results suggest that the focus of cardiovascular disease prevention in the adolescent obese should be visceral obesity, and not blood lipids or lipid subclasses.

Rapid evolution of a unique family of primate ribonuclease genes.

We have traced the rapid molecular evolution of eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP), two host defense proteins that are members of the mammalian ribonuclease gene family. The EDN/ECP gene pair arose from a recent duplication event that occurred after the divergence of New World and Old World monkeys. Since duplication, the genes encoding EDN and ECP have accumulated non-silent mutations at rates exceeding those of all other functional coding sequences studied in primates, while retaining both the structural and catalytic components required for ribonuclease activity. These results suggest that both EDN and ECP may be responding to unusual evolutionary constraints, which has prompted a reexamination of their physiologic function.

Human eosinophil cationic protein. Molecular cloning of a cytotoxin and helminthotoxin with ribonuclease activity.

We have isolated a 725-bp full-length cDNA clone for the human eosinophil cationic protein (ECP). ECP is a small, basic protein found in the matrix of the eosinophil's large specific granule that has cytotoxic, helminthotoxic, and ribonuclease activity, and is a member of the ribonuclease multigene family. The cDNA sequence shows 89% sequence identity with that reported for the related granule protein, eosinophil-derived neurotoxin (EDN). The open reading frame encodes a previously unidentified 27-amino acid leader sequence preceding a 133-residue mature ECP polypeptide with a molecular mass of 15.6 kD. The encoded amino acid sequence of ECP shows 66% identity to that of EDN and 31% identity to that of human pancreatic ribonuclease, including conservation of the essential structural cysteine and cataytic lysine and histidine residues. mRNA for ECP was detected in eosinophil-enriched peripheral granulocytes and in a subclone of the promyelocytic leukemia line, HL-60, induced toward eosinophilic differentiation with IL-5. No ECP mRNA was detected in uninduced HL-60 cells, or in HL-60 cells induced toward monocytic differentiation with vitamin D3 or toward neutrophilic differentiation with DMSO. In contrast, mRNA for EDN was detected in uninduced HL-60 cells and was upregulated in HL-60 cells induced with DMSO. Despite similarities in sequence and cellular localization, these results suggest that ECP and EDN are subject to different regulatory mechanisms.

Highly reiterated sequences of SIMIANSIMIANSIMIANSIMIANSIMIAN.

A 172-base pair segment of DNA that is repeated several million times in the genome of the African green monkey has been characterized. Sequence analysis revealed that the many repeats of this complex unit are not all identical but represent a set of closely related segments: Sequence divergence occurs at various positions in the segment in a nonrandom manner. The uncloned segment obtained from monkey DNA is compared with a cloned segment of the same DNA which was recombined into the genome of simian virus 40 during permissive infection.

Stink of Stinkpot Turtle Identified: ohgr-Phenylalkanoic Acids.

The exocrine secretion of the "stinkpot turtle," Sternotherus odoratus, discharged by the animals in response to disturbance, contains four omega-phenylalkanoic acids (phenylacetic, 3-phenylpropionic, 5-phenylpentanoic, and 7-phenylheptanoic). The last two of these are new natural products. The first two are powerfully malodorous and responsible for the stench of the fluid. Lesser components, including several aliphatic acids, are also present. Only a few milligrams of secretion are discharged by a turtle at any one time. Although bioassays with fish suggest that the secretion has the potential to serve as a feeding deterrent to predators, it is argued that Sternotherus does not ordinarily discharge enough fluid to effect this action and may employ its secretion only as an aposematic signal that warns predators of its more generalized undesirability.

Close Cassini flybys of Saturn's ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus.

Saturn's main ring system is associated with a set of small moons that either are embedded within it or interact with the rings to alter their shape and composition. Five close flybys of the moons Pan, Daphnis, Atlas, Pandora, and Epimetheus were performed between December 2016 and April 2017 during the ring-grazing orbits of the Cassini mission. Data on the moons' morphology, structure, particle environment, and composition were returned, along with images in the ultraviolet and thermal infrared. We find that the optical properties of the moons' surfaces are determined by two competing processes: contamination by a red material formed in Saturn's main ring system and accretion of bright icy particles or water vapor from volcanic plumes originating on the moon Enceladus.

Annual report to the nation on the status of cancer (1973 through 1998), featuring cancers with recent increasing trends.

BACKGROUND: The American Cancer Society, the National Cancer Institute (NCI), the North American Association of Central Cancer Registries, and the Centers for Disease Control and Prevention, including the National Center for Health Statistics (NCHS), collaborate to provide an annual update on cancer occurrence and trends in the United States. This year's report contains a special feature that focuses on cancers with recent increasing trends. METHODS: From 1992 through 1998, age-adjusted rates and annual percent changes are calculated for cancer incidence and underlying cause of death with the use of NCI incidence and NCHS mortality data. Joinpoint analysis, a model of joined line segments, is used to examine long-term trends for the four most common cancers and for those cancers with recent increasing trends in incidence or mortality. Statistically significant findings are based on a P value of.05 by use of a two-sided test. State-specific incidence and death rates for 1994 through 1998 are reported for major cancers. RESULTS: From 1992 through 1998, total cancer death rates declined in males and females, while cancer incidence rates declined only in males. Incidence rates in females increased slightly, largely because of breast cancer increases that occurred in some older age groups, possibly as a result of increased early detection. Female lung cancer mortality, a major cause of death in women, continued to increase but more slowly than in earlier years. In addition, the incidence or mortality rate increased in 10 other sites, accounting for about 13% of total cancer incidence and mortality in the United States. CONCLUSIONS: Overall cancer incidence and death rates continued to decline in the United States. Future progress will require sustained improvements in cancer prevention, screening, and treatment.

Annual report to the nation on the status of cancer, 1973-1996, with a special section on lung cancer and tobacco smoking.

BACKGROUND: The American Cancer Society, the National Cancer Institute (NCI), and the Centers for Disease Control and Prevention (CDC), including the National Center for Health Statistics (NCHS), provide the second annual report to the nation on progress in cancer prevention and control, with a special section on lung cancer and tobacco smoking. METHODS: Age-adjusted rates (using the 1970 U.S. standard population) were based on cancer incidence data from NCI and underlying cause of death data compiled by NCHS. The prevalence of tobacco use was derived from CDC surveys. Reported P values are two-sided. RESULTS: From 1990 through 1996, cancer incidence (-0.9% per year; P = .16) and cancer death (-0.6% per year; P = .001) rates for all sites combined decreased. Among the 10 leading cancer incidence sites, statistically significant decreases in incidence rates were seen in males for leukemia and cancers of the lung, colon/rectum, urinary bladder, and oral cavity and pharynx. Except for lung cancer, incidence rates for these cancers also declined in females. Among the 10 leading cancer mortality sites, statistically significant decreases in cancer death rates were seen for cancers of the male lung, female breast, the prostate, male pancreas, and male brain and, for both sexes, cancers of the colon/rectum and stomach. Age-specific analyses of lung cancer revealed that rates in males first declined at younger ages and then for each older age group successively over time; rates in females appeared to be in the early stages of following the same pattern, with rates decreasing for women aged 40-59 years. CONCLUSIONS: The declines in cancer incidence and death rates, particularly for lung cancer, are encouraging. However, unless recent upward trends in smoking among adolescents can be reversed, the lung cancer rates that are currently declining in the United States may rise again.

Phosphonopyruvic acid: A probable precursor of phosphonic acids in cell-free preparation of Tetrahymena.

1. In cell-free preparations of Tetrahymena, doubly labelled [32P]phosphoenol-[3-14C]pyruvate gives rise to 2-aminoethylphosphonate and 2-amino-3-phosphonopropionate, labelled with the two isotopes in the same ratio as the starting compound. The result is consistent with an intra-molecular rearrangement of phosphoenolpyruvate in the biosynthetic sequence of carbon-phosphorus bond formation. 2. Incubation of [32P]phosphoenolpyruvate with the same preparation, followed by treatment with 2,4-dinitrophenylhydrazine, yielded labelled hydrazones. When these were subjected to hydrogenolysis, the radioactivity was recovered in 2-aminoethylphosphonate and 2-amino-3-phosphonopropionate, suggesting that 2-phosphonoacetaldehyde and 3-phosphonopyruvic acid were probable precursors of the aminoalkylphosphonic acids. 3. Radioactivity from 2-amino-3-phosphono-[3-14C]propionic acid was incorporated into 2-aminoethylphosphonic acid, but incorporation of the radioactivity into lipids was negligible.

Phosphate transport in membrane vesicles from Escherichia coli.

Escherichia coli strain AN710 possesses only the PIT system for phosphate transport. Membrane vesicles from this strain, which contain phosphate internally, perform exchange and active transport of phosphate. The energy for active transport is supplied by the respiratory chain with ascorbate phenazine methosulphate as electron donor. To a lesser extent also the oxidation of D-lactate energizes phosphate transport; the oxidation of succinate is only marginally effective. Phosphate transport is driven by the proton-motive force and in particular by the pH gradient across the membrane. This view is supported by the observation that phosphate transport is stimulated by valinomycin, inhibited by nigericin and abolished by the uncoupler carbonyl cyanide m-chlorophenylhydrazone. Neither inhibitor affects phosphate exchange. The phosphate analogue arsenate inhibits both the exchange reaction and active transport. Both processes are stimulated by K+ and Mg2+, the highest activities being observed with both ions present. Membrane vesicles have also been isolated from Escherichia coli K10, a strain which possesses only a functional PST phosphate transport system. These vesicles perform neither exchange nor active transport of phosphate, although active transport of amino acids is observed in the presence of ascorbate-phenazine methosulphate or D-lactate.

Studies of phosphate transport in Escherichia coli. I. Reexamination of the effect of osmotic and cold shock on phosphate uptake and some attempts to restore uptake with phosphate binding protein.

1. The first stage of osmotic shock caused a slight reduction in the primary uptake of inorganic orthophosphate (Pi) in AB3311 cells of Escherichia coli which normally exhibit a biphasic type of phosphate uptake. The second stage of osmotic shock resulted in a marked reduction (a total of 80-85%) in the primary uptake phase and a lesser reduction (50%) in the secondary uptake. When osmotically shocked cells are allowed to recover in a phosphate-free, but otherwise complete medium sufficient repair occurs in the shocked cells to overcome growth lags and to restore the above losses in phosphate uptake almost to normal after 90-180 min of recovery. 2. Extensive investigation was made of the more mild cold shock procedure which involves the rapid disperion of Escherichia coli cells into 80 vol. of water at 2 degrees C. The most consistent cold shock effects, as evidenced by reductions in phosphate uptake, were obtained in cells after they were washed in appropriate buffered salts media, suspended in a minimal volume of water and shocked from 37 degrees C rather than 24 degrees C. Less severe shocks were obtained after washing in imidazole/salts/glucose or Tris/salts/glucose media than in NaCl/Tris. 3. A number of attempts were made to restore by the addition of phosphate binding protein the reduction in phosphate uptake of E. coli AB3311 cells caused by a variety of cold shocks. In no instance was good restoration of phosphate uptake achieved. Qualitatively, it appeared that a better restoration of uptake occurred in unstarved and starved cells washed in imidazole/salts/glucose where the cold shock effect was less severe.

Ribonucleases and host defense: identification, localization and gene expression in adherent monocytes in vitro.

Several ribonucleases of the RNase A family function as antibacterial, anti-parasitic and anti-viral agents. In this work, we have shown that mRNAs encoding five of the six known human ribonucleases of the RNase A family are expressed in cultured human monocytes, and that ribonucleases are released by adherent monocytes in culture. Using a polyclonal antiserum prepared against recombinant protein, we have detected one of these ribonucleases, RNase 4, in lysates of normal human peripheral blood monocytes, but not granulocytes or lymphocytes, by Western blotting. Subcellular localization by immunoelectron microscopy demonstrated the presence of RNase 4 in the cytoplasmic granules of isolated monocytes. Interestingly, mRNA encoding RNase 4 could not be detected in freshly isolated monocytes, emerging only after 16 h in culture, suggesting the possibility of de novo protein synthesis in association with monocyte differentiation.

Glucosylated collagen is antigenic.

Sera from rats inoculated with in vitro glucosylated rat skin acid-soluble collagen were evaluated for specific antibody response using the enzyme-linked immunosorbent assay. The data indicate that the altered protein is capable of eliciting the production of antibodies, but unmodified collagen is not. The specificity of the generated antibodies appears to be directed toward the glucitollysine residues of the modified collagen. Sera from streptozotocin-induced diabetic rats contain antibodies that clearly bind glucosylated collagen. These results provide support for the hypothesis that in diabetes mellitus increased collagen glucosylation during chronic hyperglycemia may be the initiating event of an autoimmune response leading to the long-term complications.

Sequence variation at two eosinophil-associated ribonuclease loci in humans.

Host defense against invading pathogens is of great importance to the survival of higher organisms. We have been studying the evolution of mammalian eosinophil-associated ribonucleases (EARs), which are members of the ribonuclease A superfamily with known antipathogen activities. Earlier studies showed that positive selection promoted rapid diversification of paralogous EAR genes in both primates and rodents. Intraspecifically, however, it is unknown whether these genes also have divergent alleles. The recent discovery that the gene repertoire of the EAR family is much larger in rodents than in primates has led us to consider the possibility that primates maintain a large number of polymorphic alleles to compensate for a smaller gene repertoire. Here we present sequences of 2417 nucleotides at the two EAR loci, the eosinophil-derived neurotoxin (EDN, RNase 2) and eosinophil cationic protein (ECP, RNase 3), from >50 human individuals. Our data demonstrate that the nucleotide diversities (0.06-0.11%) at these loci are typical for human nuclear genes, thus permitting us to reject this polymorphism hypothesis. No significant departure from neutrality is noted and no signs of overdominant selection are observed. Similar patterns were observed in a preliminary study of chimpanzees. In summary, our results suggest that the antipathogen functions of the primate EARs are conserved after they are established and that these proteins are not currently undergoing rapid diversification in response to challenge from invading microorganisms.

Eosinophils, eosinophil ribonucleases, and their role in host defense against respiratory virus pathogens.

Eosinophils remain among the most enigmatic of cells, as our appreciation of their detrimental activities--e.g., asthma and allergic disease--far outweighs our understanding of their beneficial effects. Among the major secretory effector proteins of eosinophils are the ribonucleases eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP) in primates and their orthologs, the eosinophil-associated ribonucleases (EARs) in rodents. The rapid diversification observed among these ribonucleases suggested that the ultimate target(s) might be similarly efficient at generating sequence diversity while maintaining an unalterable susceptibility to ribonucleolytic cleavage. This has prompted us to consider a role for these proteins and by extension, for eosinophils, in host defense against single-stranded RNA virus pathogens. We detail our studies of the antiviral activity of eosinophils and eosinophil ribonucleases against respiratory syncytial virus (RSV) in vitro and the related, natural rodent pathogen, pneumonia virus of mice (PVM), in vivo, and consider the possibility that antiviral host defense and the dysregulated responses leading to asthma represent opposing sides of an eosinophil-mediated double-edged sword.