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1.
Adv Neonatal Care ; 22(5): E169-E181, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-35588063

ABSTRACT

BACKGROUND: Black mothers and their very low birth-weight infants in the United States have increased risk of adverse neonatal and maternal health outcomes compared with White mothers and infants. Disparities in adverse birth outcomes associated with sociodemographic factors are difficult to quantify and modify, limiting their usefulness in assessing intervention effects. PURPOSE: To test hypotheses that (1) the biological factors of maternal testosterone and cortisol are associated with sociodemographic factors and (2) both factors are associated with neonatal health and maternal mental health and healthy behaviors between birth and 40 weeks' gestational age. METHODS: We used a descriptive, longitudinal design. Eighty-eight mothers and very low birth-weight neonates were recruited from a tertiary medical center in the United States. Data on sociodemographic factors and neonatal health were collected from medical records. Maternal mental health and healthy behaviors were collected with questionnaires. Maternal salivary testosterone and cortisol levels were measured using enzyme immunoassays. Data were analyzed primarily using general linear and mixed models. RESULTS: High testosterone and/or low cortisol levels were associated with younger age, less education, enrollment in a federal assistance program, being unmarried, being Black, poorer neonatal health, and delayed physical growth. Low cortisol level was related to higher levels of depressive symptoms. Black mothers had fewer healthy behaviors than White mothers. IMPLICATIONS FOR PRACTICE AND RESEARCH: Findings confirm that biological factors are associated with sociodemographic factors, and both are associated with neonatal health and maternal mental health and healthy behaviors. We propose using sociodemographic and biological factors concurrently to identify risk and develop and evaluate ante- and postpartum interventions.Video abstract available athttps://journals.na.lww.com/advancesinneonatalcare/Pages/videogallery.aspx?autoPlay=false&videoId=59.


Subject(s)
Hydrocortisone , Mothers , Biological Factors , Female , Humans , Infant , Infant, Newborn , Infant, Very Low Birth Weight , Mothers/psychology , Testosterone , United States/epidemiology
2.
Biol Res Nurs ; 23(4): 646-657, 2021 10.
Article in English | MEDLINE | ID: mdl-34000839

ABSTRACT

AIMS: This critical review aimed to summarize: (1) the variability and determinants of testosterone (T) measurements; and (2) reference values for the variability and determinants of T measurements in children. BACKGROUND: As T is a representative androgen, it has been widely used to explain male vulnerability to child health and developmental problems. T measurements in children, however, have been challenging because of low levels, diurnal and episodic secretion patterns, limited quantity and quality of the samples, and inconsistent study findings. METHODS: The search strategy used PubMed, CINAHL, Cochrane Library, Embase, Scopus, and Google Scholar. Studies published between 2008 through 2020 that examined factors influencing T measurement were included. The final 30 studies were selected using two appraisal forms. We extracted five categories of data from the reports. FINDINGS: Variability and determinants of T measurement included assay methods, the source of samples, and child demographic and environmental characteristics. T levels were higher 1-3 months after birth and in males up to 1 year; fewer sex differences were found up to 10-12 years. Serum T levels measured by using liquid chromatography-mass spectrometry were most reliable because immunoassays overestimated the levels, especially in neonates. T levels were stable at different temperatures and durations of storage, although sample collection remained an ongoing challenge for researchers. CONCLUSION: Depending on the study aims and feasibility, mass-spectrometry, multi-methods, and multi-materials are the recent trends in T measurement. Immunoassays may be an option if the study aims for relative rather than absolute comparisons.


Subject(s)
Testosterone , Child , Chromatography, Liquid , Female , Humans , Infant, Newborn , Male , Mass Spectrometry
3.
Biol Res Nurs ; 23(2): 188-197, 2021 04.
Article in English | MEDLINE | ID: mdl-32700638

ABSTRACT

BACKGROUND: Testosterone levels have been used to examine infant boys' vulnerability to health and developmental problems, following the general theories of gender differences and the theory of extreme male brain of autism. OBJECTIVES: As testosterone is a representative androgen hormone and is higher in preterm than full-term infants, we used this steroid to determine if hypothalamic pituitary hormones, testosterone, and cortisol, were related to physical growth, health, and development of very-low-birthweight (VLBW, BW < 1,500 g) infants. METHOD: For this comparative longitudinal study, 40 VLBW infants were recruited from a neonatal intensive care unit of a tertiary medical center. Data were collected from medical record reviews, questionnaires, and assessments of infant development at 6, 12, and 24 months. We collected saliva at the three time points and measured hormones using enzyme-immunoassays. RESULTS: General and generalized mixed models showed that a 1pg/ml increment of testosterone was related to a -0.42% decrease in body weight, a -0.18% decrease in length, and a -0.10% decrease in head circumference. Cortisol levels were not associated with any outcome variable. The interactions between testosterone and time on physical growth and socioemotional development also occurred. DISCUSSION: Elevated testosterone levels can be a biological risk factor for poor infant growth and development. Theories about the effects of elevated prenatal testosterone could be useful in predicting health and developmental outcomes among VLBW infants. Research beyond the first 2 years will be needed as infants show more socioemotional and behavioral problems as they grow older.


Subject(s)
Child Development/physiology , Infant, Premature/growth & development , Testosterone/metabolism , Biomarkers/metabolism , Humans , Hydrocortisone/metabolism , Infant , Infant, Newborn , Infant, Premature/metabolism , Infant, Very Low Birth Weight , Intensive Care Units, Neonatal/statistics & numerical data , Longitudinal Studies , Male , Saliva/metabolism , Sex Factors
4.
J Perinat Neonatal Nurs ; 34(4): E32-E43, 2020.
Article in English | MEDLINE | ID: mdl-33079812

ABSTRACT

This study was conducted to confirm the negative associations between testosterone and cortisol levels and health and developmental outcomes in very low-birth weight (VLBW) infants after controlling for prenatal glucocorticoid (GC) treatment. Seventy-four VLBW infant-mother pairs were recruited from a neonatal intensive care unit in the Southeastern United States. We divided the pairs into the complete (n = 58) and incomplete (n = 16) GC treatment groups. Data on infants and mothers were obtained at birth, 40 weeks' postmenstrual age, and 3 and 6 months' corrected age. Salivary testosterone and cortisol levels of the pairs were determined at 40 weeks' postmenstrual age using enzyme immunoassay. Log-linear and general linear mixed models showed that gestational age and birth weight were lower when testosterone was 1 pg/mL higher. When cortisol was 1 µg/dL higher, technology dependence at discharge was higher and motor development at 6 months was lower. Mothers with complete GC treatment had greater parity and gravida, more prenatal visits, and more medical complications. The study outcomes supported our hypothesis that steroid hormonal levels are more predictive of infant health and development than GC treatment completeness. Single dose of GC treatment might be just as effective as 2 doses, although further study with more subjects would be needed to confirm. As the associations with steroid hormonal levels lasted longer than the GC treatment associations, we recommend confirming the predictive effects of testosterone and cortisol levels after 6 months.


Subject(s)
Glucocorticoids , Hydrocortisone/analysis , Prenatal Exposure Delayed Effects , Saliva/metabolism , Testosterone/analysis , Child Development/drug effects , Duration of Therapy , Female , Gestational Age , Glucocorticoids/administration & dosage , Glucocorticoids/adverse effects , Humans , Infant Health , Infant, Newborn , Infant, Very Low Birth Weight , Intensive Care Units, Neonatal/statistics & numerical data , Male , Pregnancy , Prenatal Care/methods , Prenatal Exposure Delayed Effects/diagnosis , Prenatal Exposure Delayed Effects/metabolism , Prognosis
5.
Ophthalmic Surg Lasers Imaging Retina ; 51(7): 392-400, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32706897

ABSTRACT

BACKGROUND AND OBJECTIVE: To characterize contrast sensitivity function (CSF) in patients with retinal vein occlusion (RVO) compared to age-matched controls using novel computerized contrast sensitivity (CS) testing with active learning algorithms. PATIENTS AND METHODS: CSF was prospectively measured in RVO patients with visual acuity (VA) greater than 20/200 and age-matched controls using the novel Manifold Contrast Vision Meter implementing quantitative CSF testing. Outcomes included area under the Log CSF (AULCSF), contrast acuity (CA), and CS thresholds at 1, 1.5, 3, 12, and 18 cycles per degree (cpd). A sub-analysis was performed on RVO eyes with good acuity (VA ≥ 20/30). RESULTS: Twenty-two eyes with RVO and 63 control eyes were included. Mean AULCSF (± standard deviation) in RVO eyes was 0.817 (0.28) compared to 1.217 (0.28) in controls (P < .0001). Mean contrast acuity in the RVO group was 1.054 (0.19) versus 1.286 ± 0.16 in controls (P < .0001). For individual spatial frequencies, CS loss at 6.0 cpd was most prominent in the RVO group. In 10 RVO eyes with VA of 20/30 or greater, mean AULCSF was 0.978 versus 1.217 in control eyes. (P = .008). CONCLUSIONS: CSF in eyes with RVO was found to be significantly reduced compared to age-matched controls. CSF seems to be a promising visual function endpoint with potential applications in clinical practice and future clinical trials. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:392-400.].


Subject(s)
Contrast Sensitivity/physiology , Learning/physiology , Retinal Vein Occlusion/physiopathology , Visual Acuity , Female , Fluorescein Angiography/methods , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Retinal Vein Occlusion/diagnosis , Tomography, Optical Coherence/methods
6.
J Med Ultrasound ; 27(2): 75-80, 2019.
Article in English | MEDLINE | ID: mdl-31316216

ABSTRACT

OBJECTIVES: The objective of this study was to find the diagnostic values of additional ultrasound (US) in patients with equivocal computed tomography (CT) findings of acute appendicitis, compared to CT reassessment. MATERIALS AND METHODS: Patients with equivocal CT findings of acute appendicitis (n = 115), who underwent the US, were included in the study. Two abdominal radiologists reviewed CT scans independently. They analyzed CT findings and made a diagnosis of acute appendicitis. The patients were categorized into positive and negative appendicitis based on the previous US reports. The diagnostic performance, interobserver agreement of CT findings, and appendicitis likelihood were calculated. RESULTS: The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of US (100%, 92.1%, 79.5%, and 100%, respectively) were higher than those of CT reassessment (reviewer 1: 51.9%, 87.5%, 56.1%, and 85.6%; reviewer 2: 66.7%, 85.2%, 58.1%, and 89.3%, respectively). In the coexistent inflammation group, the sensitivity, specificity, PPV, and NPV of US (reviewer 1: 100%, 98%, 91.5%, and 100%; reviewer 2: 100%, 98%, 87.7%, and 100%, respectively) were higher than those of CT reassessment (reviewer 1: 27.3%, 94.1%, 49.9%, and 85.8%; reviewer 2: 14.3%, 98.0%, 50.5%, and 88.9%, respectively). CONCLUSION: In patients with equivocal CT findings of acute appendicitis, US shows better diagnostic performance than CT reassessment, and helps differentiate with periappendicitis.

7.
Biol Res Nurs ; 21(3): 253-263, 2019 05.
Article in English | MEDLINE | ID: mdl-30764642

ABSTRACT

OBJECTIVES: To examine the concurrent use of self-report questionnaires and hormonal biomarkers, specifically levels of testosterone and cortisol, along with demographic variables and corrected age (CA) in the assessment of mental health and healthy behaviors among mothers of very-low-birthweight (VLBW, BW < 1,500 g) infants at five time points over 2 years post birth. METHOD: Data on 40 mothers from a neonatal intensive care unit of a tertiary medical center in the southeast United States were collected from the medical record, standard questionnaires for the mother (depressive symptoms, perceived stress, anxiety, mental health status, parenting stress, and healthy lifestyle behaviors), and biochemical measurement of maternal testosterone and cortisol using enzyme immunoassay at birth, 40 weeks' postmenstrual age, and 6, 12, and 24 months CA. RESULTS: Maternal self-report of mental health improved from birth to 6 or 12 months then worsened at 24 months. Mixed linear models showed that mothers with higher testosterone levels had more depressive symptoms and smoked more, whereas mothers with higher cortisol levels had healthier behaviors and exercised more. Testosterone levels were negatively correlated with cortisol levels. Marital status, education, and health insurance were the most predictive demographic variables for the levels of hormonal biomarkers, mental health, and healthy behaviors. CONCLUSIONS: The use of self-report and biochemical measurement was effective in assessing maternal mental health and healthy behaviors over 2 years post birth, when mothers of VLBW infants tend to experience more mental health problems and parenting difficulties than mothers of normal-BW full-term infants.


Subject(s)
Biomarkers/blood , Health Behavior/physiology , Hydrocortisone/blood , Infant, Very Low Birth Weight/psychology , Mental Disorders/physiopathology , Mothers/psychology , Testosterone/blood , Adult , Female , Humans , Infant , Infant, Newborn , Intensive Care Units, Neonatal , Male , Mental Health , Pregnancy , Southeastern United States
8.
Ultrasound Med Biol ; 43(11): 2515-2521, 2017 11.
Article in English | MEDLINE | ID: mdl-28844464

ABSTRACT

We investigated the feasibility of using ultrasound shear wave elastography point quantification (ElastPQ) for liver fibrosis staging and compared it with other non-invasive tools with respect to efficacy in liver stiffness measurement. A total of 106 patients who underwent liver stiffness measurements, using ElastPQ and biochemical investigations, before parenchymal liver biopsy or surgery were included. Among these, 51 also underwent transient elastography (TE). Correlations of ElastPQ, TE and aspartate aminotransferase-to-platelet ratio index (APRI) with histopathological findings (as the reference standard) were determined using Spearman's correlation coefficient. The diagnostic performance of ElastPQ, TE and APRI was evaluated using receiver operating characteristic (ROC) curve analysis. ElastPQ had good diagnostic accuracy in identifying each liver fibrosis stage, with an area under the ROC curve (AUC) of 0.810 to 0.864. Stiffness values obtained using ElastPQ, TE and APRI were significantly positively correlated (r = 0.686, r = 0.732 and r = 0.454, respectively) with histologic fibrosis staging (p < 0.001). According to the AUC for the diagnosis of significant fibrosis (≥F2) and cirrhosis (=F4), ElastPQ had better diagnostic accuracy (AUC = 0.929 and 0.834, respectively) than APRI (AUC = 0.656 and 0.618, respectively) (p < 0.05), and was similar to TE (AUC = 0.915 and 0.879, respectively). ElastPQ is a promising ultrasound-based imaging technique for evaluation of liver fibrosis, with a diagnostic accuracy comparable to that of TE.


Subject(s)
Elasticity Imaging Techniques/methods , Liver Cirrhosis/blood , Liver Cirrhosis/diagnostic imaging , Liver/diagnostic imaging , Liver/pathology , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Biopsy , Feasibility Studies , Female , Humans , Liver Cirrhosis/pathology , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Severity of Illness Index , Young Adult
9.
Nurs Res ; 66(5): 350-358, 2017.
Article in English | MEDLINE | ID: mdl-28661908

ABSTRACT

BACKGROUND: Male infants are more prone to health problems and developmental delays than female infants. OBJECTIVES: On the basis of theories of gender differences in brain development and social relationships, we explored associations between testosterone and cortisol levels with infant cognitive, motor, and language development ("infant development") in very low birth weight (VLBW) infants, controlling for mother-infant interactions, characteristics of mothers and infants, and days of saliva collection after birth. METHODS: A total of 62 mother-VLBW infant pairs were recruited from the newborn intensive care unit of a tertiary medical center in the Southeast United States. Data were collected through infant medical record review, biochemical measurement, observation of mother-infant interactions, and standard questionnaires. Infant development was assessed at 6 months corrected age (CA), and mother-infant interactions were observed at 3 and 6 months CA. RESULTS: General linear regression with separate analyses for each infant gender showed that high testosterone levels were positively associated with language development of male infants after controlling for mother-infant interactions and other covariates, whereas high cortisol levels were negatively associated with motor development of female infants after controlling for mother-infant interactions. CONCLUSIONS: Steroid hormonal levels may well be more fundamental factors for assessing infant development than infant gender or mother-infant interactions at 6 months CA.


Subject(s)
Biomarkers/blood , Brain/growth & development , Child Development/physiology , Hydrocortisone/analysis , Infant, Very Low Birth Weight/growth & development , Saliva/chemistry , Testosterone/analysis , Humans , Infant, Newborn , Language , Male , Mother-Child Relations , Sex Factors , Southeastern United States
10.
Biol Res Nurs ; 19(4): 409-418, 2017 07.
Article in English | MEDLINE | ID: mdl-28399640

ABSTRACT

OBJECTIVE: Although the roles of testosterone and cortisol in various health problems have been extensively investigated, little is known about their associations with health outcomes in mothers and their very-low-birthweight (VLBW) infants when maternal testosterone and cortisol are examined together during the postpartum period. METHOD: The 101 mother-VLBW infant pairs were recruited from the neonatal intensive care unit of a tertiary medical center in the southeastern United States. Demographic information, pregnancy and labor complications of mothers, and health and growth outcomes of infants were obtained from medical records and interviews with mothers. Maternal salivary testosterone and cortisol levels were determined using enzyme immunoassay. RESULTS: Linear regression showed that mothers who were older and had a larger body mass index experienced more pregnancy complications, whereas mothers who were single and had a cesarean section experienced more labor complications. Generalized linear models showed that mothers with high cortisol levels had more antepartum hemorrhage, whereas infants of mothers with high cortisol levels had fewer neurological insults and shorter hospitalizations than other infants. More mothers experienced premature prolonged rupture of membranes (PPROM) than chorioamnionitis, and maternal medical complications were negatively associated with infant health outcomes except PPROM, which was positively associated with infant outcomes. CONCLUSIONS: High maternal cortisol levels were associated with maternal health problems during pregnancy. Beneficial effects of PPROM and high maternal cortisol levels on infant health outcomes were important findings, and understanding the mechanisms of these relationships may be of practical value for clinicians and researchers.


Subject(s)
Hydrocortisone/analysis , Infant Health , Maternal Health , Pregnancy Complications/physiopathology , Testosterone/analysis , Adult , Female , Humans , Infant , Infant, Newborn , Infant, Very Low Birth Weight , Mothers , Postpartum Period , Pregnancy , Southeastern United States
11.
Korean J Radiol ; 17(5): 734-41, 2016.
Article in English | MEDLINE | ID: mdl-27587962

ABSTRACT

OBJECTIVE: To evaluate the diagnostic performance of obliteration of normal heterogeneous enhancement of the spleen (ONHES) on arterial phase (AP) computed tomography (CT) images in diffuse infiltrative splenic lymphoma (DISL). MATERIALS AND METHODS: One hundred and thirty-six patients with lymphoma who had undergone two-phase (arterial and portal venous) abdominal CT were included in this study. We retrospectively evaluated the diagnostic performance of ONHES on AP CT in diagnosing DISL. Two observers evaluated ONHES on AP CT using the 5-point confidence level and assessed the presence or absence of subjective splenomegaly on axial CT images. Another two observers measured the splenic index as proposed by objective CT criteria. Statistical analysis included interobserver agreement and diagnostic performance of CT findings. RESULTS: Eleven of the 136 patients with lymphoma had DISL. The area under the receiver operating characteristic curve of ONHES (0.948 for observer 1 and 0.922 for observer 2) was superior to that of the splenic index (0.872 for observer 3 and 0.877 for observer 4), but the difference was not statistically significant (p > 0.05). The diagnostic performance of ONHES in conjunction with subjective splenomegaly showed higher diagnostic performance, as compared with subjective splenomegaly alone (accuracy: 100% and 85.3% for observer 1, 98.5% and 87.5% for observer 2; positive predictive value: 100% and 35.5% for observer 1, 90.9% and 39.3% for observer 2, respectively). CONCLUSION: Obliteration of normal heterogeneous enhancement of the spleen in conjunction with subjective splenomegaly can improve the diagnostic performance for DISL. Our results suggest that ONHES on AP CT images could be useful as an adjunctive diagnostic indicator of DISL in patients with lymphoma.


Subject(s)
Lymphoma/diagnostic imaging , Splenic Neoplasms/diagnostic imaging , Adult , Aged , Aged, 80 and over , Female , Humans , Image Interpretation, Computer-Assisted/methods , Lymphoma/complications , Male , Middle Aged , Observer Variation , Positron Emission Tomography Computed Tomography/methods , ROC Curve , Retrospective Studies , Splenic Neoplasms/complications , Splenomegaly/diagnostic imaging , Splenomegaly/etiology , Tomography, X-Ray Computed/methods , Young Adult
12.
Biol Res Nurs ; 18(1): 31-42, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25954021

ABSTRACT

This study examined the associations of testosterone and cortisol levels with maternal depressive symptoms and infant socioemotional (SE) problems that are influenced by infant gender. A total of 62 mothers and their very-low-birth weight (VLBW) infants were recruited from a neonatal intensive care unit at a tertiary medical center in the southeast United States. Data were collected at three time points (before 40 weeks' postmenstrual age [PMA] and at 3 months and 6 months of age corrected for prematurity). Measures included infant medical record review, maternal interview, biochemical assays of salivary hormone levels in mother-VLBWinfant pairs, and standard questionnaires. Generalized estimating equations with separate analyses for boys and girls showed that maternal testosterone level was negatively associated with depressive symptoms in mothers of boys, whereas infant testosterone level was negatively associated with maternal report of infant SE problems in girls after controlling for characteristics of mothers and infants and number of days post birth of saliva collection. Not surprisingly, the SE problems were positively associated with a number of medical complications. Mothers with more depressive symptoms reported that their infants had more SE problems. Mothers with higher testosterone levels reported that girls, but not boys, had fewer SE problems. In summary, high levels of testosterone could have a protective role for maternal depressive symptoms and infant SE problems. Future research need to be directed toward clinical application of these preliminary results.


Subject(s)
Depression/physiopathology , Hydrocortisone/analysis , Infant, Premature/physiology , Infant, Very Low Birth Weight/physiology , Mothers/psychology , Saliva/chemistry , Testosterone/analysis , Adult , Child, Preschool , Depression/psychology , Female , Humans , Infant , Infant, Newborn/psychology , Infant, Premature/psychology , Intensive Care Units, Neonatal , Male , Middle Aged , Sex Factors , Southeastern United States , Time Factors , United States
14.
Res Nurs Health ; 38(5): 357-68, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26152823

ABSTRACT

Male very-low-birthweight (VLBW) infants are more prone than females to health and developmental problems and less positive mother-infant interactions. Because gender differences in brain development and social relationships suggest hormonal influences on quality of mother-infant interaction, the authors explored the associations of maternal and infant salivary testosterone and cortisol levels with mother-infant interactions in the sample as a whole and by gender, after controlling for covariates. Data were collected prospectively from 62 mothers and their VLBW infants through infant record review, maternal interview, biochemical measurement of both mothers and infants, and observation of mother-infant interactions at 40 weeks postmenstrual age and at three and six months corrected age. Infants' positive interactions increased and mothers' decreased from three to six months. In generalized estimating equation (GEE) analyses, after controlling for covariates, higher maternal testosterone and infant cortisol were associated with more positive and more frequent maternal interactive behaviors. In GEE analyses by infant gender, after controlling for covariates, effects of maternal and infant hormone levels became more significant, especially on infants' interactive behaviors. Based on these preliminary findings, among VLBW infants, males with high testosterone are expected to have less positive mother-infant interactions than males with low testosterone or female infants.


Subject(s)
Hydrocortisone/analysis , Infant, Low Birth Weight/metabolism , Mother-Child Relations , Saliva/chemistry , Testosterone/analysis , Adult , Child Development/physiology , Female , Humans , Infant , Infant, Newborn , Male , Sex Characteristics , Southeastern United States
15.
Appl Biochem Biotechnol ; 172(6): 3263-70, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24510482

ABSTRACT

FtsZ is an essential bacterial cell division protein that is an attractive target for the development of antibacterial agents. FtsZ is a homologue of eukaryotic tubulin, has GTPase activity, and forms a ring-type structure to initiate cell division. In this study, the FtsZ of Bacillus anthracis was cloned into a bacterial expression vector and overexpressed into Escherichia coli BL21 (DE3) cells. The overexpressed B. anthracis FtsZ was soluble and purified to homogeneity using Ni-His-tag affinity chromatography. Like other known FtsZs, the recombinant B. anthracis FtsZ also showed GTP-dependent polymerization, which was analyzed using both spectrophotometric and Transmission Electronic Microscopic (TEM) analysis. Using the purified FtsZ, we screened a naturally extracted chemical library to identify potent and novel inhibitors. The screening yielded three chemicals, SA-011, SA-059, and SA-069, that inhibited the in vitro polymerization activity of FtsZ in the micromolar range (IC50 of 55-168 µM). The inhibition potency was significantly comparable with that of berberine, a known potential inhibitor of FtsZ. Understanding the biochemical basis of the effect of these inhibitors on B. anthracis growth would provide a promising path for the development of new antianthracis drugs.


Subject(s)
Anti-Bacterial Agents/chemistry , Bacillus anthracis/chemistry , Bacterial Proteins/antagonists & inhibitors , Cytoskeletal Proteins/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Small Molecule Libraries/chemistry , Bacillus anthracis/enzymology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Berberine/chemistry , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Gene Expression , Guanosine Triphosphate/chemistry , High-Throughput Screening Assays , Protein Multimerization , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism
16.
Biol Res Nurs ; 16(2): 228-36, 2014 Apr.
Article in English | MEDLINE | ID: mdl-23639953

ABSTRACT

OBJECTIVE: Many researchers and health care providers have noticed male vulnerability in infant health, mother-infant interactions, and some infant cognitive development, especially among very low birth weight (VLBW) preterm infants. However, factors beyond gender that could explain these observed differences have not been clear. The purpose of this article is to review the literature on the subject and to introduce a conceptual framework relating these factors. DISCUSSION: According to gender-difference theories, prenatal exposure to high levels of testosterone may influence infant health and mother-infant interactions by negatively affecting infant cognitive/motor/language development. We constructed a conceptual framework based on the associations among biological (perinatal testosterone), stress-related (perinatal and maternal cortisol), and developmental (infant cognitive/motor/language skills) factors. If research establishes these biological, environmental, and developmental associations in mother-VLBW preterm pairs, the results will highlight the importance of addressing gender differences in nursing research and encourage the development of nursing interventions designed to reduce stress among mothers of VLBW preterm infants, particularly male infants. CONCLUSION: From a psychobiosocial perspective, combining biophysiological factors such as perinatal testosterone and cortisol with socioenvironmental factors such as the quality of mother-infant interactions and infant temperament may provide a broader view of gender differences in infant health and development.


Subject(s)
Child Development , Mother-Child Relations , Testosterone/blood , Depression/physiopathology , Female , Humans , Infant , Infant, Newborn , Male , Sex Factors , Temperament
17.
Cardiovasc Intervent Radiol ; 37(6): 1469-75, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24352864

ABSTRACT

PURPOSE: This study was designed to evaluate retrospectively the efficacy of C-arm CT to confirm right adrenal vein catheterization during adrenal vein sampling (AVS) and to correlate adrenal venography findings with C-arm CT and/or biochemical results for right adrenal vein selection. METHODS: Forty-two consecutive primary aldosteronism patients (M:F = 21:21; age: 29-70 years) underwent C-arm CT assisted sequential AVS. After catheterization of right adrenal vein, C-arm CT was performed to confirm catheter position. Catheter was repositioned when right adrenal gland was not opacified. Radiological images, medical records, and biochemical results were reviewed for technical/biochemical success rates and complications. Right adrenal venography findings of pinnate pattern, visualization of renal capsular vein, and retroperitoneal vein other than renal capsular vein were correlated with C-arm CT and/or biochemical results for right adrenal vein selection. RESULTS: Both the technical and biochemical success of AVS was achieved in 40 patients (95.2%). C-arm CT failed due to catheter instability in one, and adrenal/vena cava cortisol gradient was <3 in one patient. Catheter was repositioned in four patients (9.5%) according to C-arm CT findings. Right adrenal venography finding of renal capsular vein significantly correlated with C-arm CT and/or biochemical results (100%) for right adrenal vein selection (p = 0.011, χ(2) test), whereas pinnate pattern (p = 0.099) and other retroperitoneal veins (p = 0.347) did not. There was no procedure-related complication. CONCLUSIONS: C-arm CT increases confidence of right adrenal vein catheterization during AVS. Visualization of renal capsular vein on adrenal venography suggests right adrenal vein catheterization and C-arm CT may not be required.


Subject(s)
Adrenal Glands/blood supply , Hyperaldosteronism/blood , Phlebography/methods , Radiography, Interventional , Tomography, X-Ray Computed/methods , Adult , Aged , Catheterization , Female , Humans , Male , Middle Aged , Radiography, Abdominal , Retrospective Studies , Sensitivity and Specificity
18.
Biochimie ; 95(7): 1411-21, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23523771

ABSTRACT

Microbes and plants synthesize essential branched-chain amino acids (BCAAs) such as valine, leucine, and isoleucine via a common biosynthetic pathway in which the first reaction is catalyzed by acetohydroxyacid synthase (AHAS, EC 4.1.3.18). Recently, AHAS was identified as a potential anti bacterial target. To help find an effective inhibitor that could act as an antibacterial compound, we cloned and characterized the catalytic subunit (CSU) of Pseudomonas aeruginosa AHAS, and found four potent inhibitors through chemical library screening. The ilvI gene of P. aeruginosa encodes a 65-kDa AHAS protein, consistent with the size of the purified enzyme on SDS-PAGE. Enzyme kinetics showed that the enzyme has a Km of 14.2 mM and a specific activity of 0.12 U/mg. Enzyme activity was optimum at a temperature of 37 °C and a pH of 7.5. The Kd for thiamine diphosphate (ThDP) was 89.92 ± 17.9 µM, as determined by fluorescence quenching. The cofactor activation constants (Ks) for ThDP and (Kc) for Mg(2+) were 0.6 ± 0.1 and 560.8 ± 7.4 µM, respectively. Further, we determined that AVS2087, AVS2093, AVS2236, and AVS2387 compounds are potent inhibitors of the catalytic subunit of P. aeruginosa AHAS. These compounds inhibit nearly 100% of AHAS activity, with IC50 values of 1.19 µM, 5.0 nM, 25 nM, and 13 nM, respectively. Compound AVS2093 showed growth inhibition with a minimal inhibitory concentration (MIC) of 742.9 µg/ml against P. aeruginosa strain ATCC 9027. Furthermore, these findings were supported by molecular docking studies with the AVS compounds against P. aeruginosa AHAS in which AVS2093 showed minimum binding energy (-7.8 kJ/mol) by interacting with the receptor through a single hydrogen bond of 2.873 Å. Correlation of AVS2093 activity with P. aeruginosa AHAS cell growth inhibition suggested that AHAS might serve as a target protein for the development of novel antibacterial therapeutics. Results of the current study provide an impetus to further evaluate the potency of these inhibitors against pathogenic P. aeruginosa strains in vivo and to design more potent antibacterial agents based on these AVS inhibitors.


Subject(s)
Acetolactate Synthase/antagonists & inhibitors , Bacterial Proteins/antagonists & inhibitors , Pseudomonas aeruginosa/enzymology , Acetolactate Synthase/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Hydrogen Bonding , Hydrogen-Ion Concentration , Microbial Sensitivity Tests , Pseudomonas aeruginosa/drug effects , Temperature
19.
Gut Liver ; 6(4): 471-5, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23170152

ABSTRACT

BACKGROUND/AIMS: Various strategies to expand the ablation zone have been attempted using hepatic radiofrequency ablation (RFA). The optimal strategy, however, is unknown. We compared hepatic RFA with an internally cooled wet (ICW) electrode and vascular inflow occlusion. METHODS: EIGHT DOGS WERE ASSIGNED TO ONE OF THREE GROUPS: only RFA using an internally cooled electrode (group A), RFA using an ICW electrode (group B), and RFA using an internally cooled electrode with the Pringle maneuver (group C). The ablation zone diameters were measured on the gross specimens, and the volume of the ablation zone was calculated. RESULTS: The ablation zone volume was greatest in group B (1.82±1.23 cm(3)), followed by group C (1.22±0.47 cm(3)), and then group A (0.48±0.33 cm(3)). The volumes for group B were significantly larger than the volumes for group A (p=0.030). There was no significant difference in the volumes between groups A and C (p=0.079) and between groups B and C (p=0.827). CONCLUSIONS: Both the usage of an ICW electrode and hepatic vascular occlusion effectively expanded the ablation zone. The use of an ICW electrode induced a larger ablation zone with easy handling compared with using hepatic vascular occlusion, although this difference was not statistically significant.

20.
Early Hum Dev ; 88(10): 789-95, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22633533

ABSTRACT

OBJECTIVES: Male vulnerability in health and growth outcomes has often been reported in very low birth weight (VLBW) preterm neonates. On the basis of gender-difference theories, possible associations were explored between the levels of postnatal salivary testosterone/cortisol and the outcomes of neonatal health/growth. METHODS: This study used an exploratory and comparative research design. One-hundred-one mother-VLBW preterm neonate pairs were recruited from the neonatal intensive care unit (NICU) of a tertiary medical center in the Southeastern, US. Demographic information, health and growth variables of neonates, and pregnancy and labor variables of mothers were obtained from the medical record reviews and interviews of mothers. Saliva samples from each pair were collected between 9 and 60 days of age. The levels of testosterone and cortisol were determined by using an enzyme immunoassay methodology. RESULTS: Linear regression analysis showed that neonatal health problems were positively associated with the levels of postnatal salivary testosterone and cortisol, while growth delays were positively associated with the levels of postnatal salivary testosterone after adjusting for the characteristics of neonates and mothers and day of saliva sampling. The salivary levels of testosterone and cortisol were higher in neonates than in mothers. A positive correlation between the levels of testosterone and cortisol was found in neonates and in mothers. CONCLUSIONS: The level of postnatal salivary testosterone is a more reliable marker in assessing neonatal health and growth outcomes compared to salivary cortisol. Further research on both testosterone and cortisol measurements at various stages during the neonatal period may elucidate further these associations.


Subject(s)
Hydrocortisone/analysis , Infant, Very Low Birth Weight/metabolism , Saliva/chemistry , Testosterone/analysis , Adult , Androgens/analysis , Anti-Inflammatory Agents/analysis , Female , Humans , Infant, Newborn , Infant, Premature/growth & development , Infant, Premature/metabolism , Infant, Very Low Birth Weight/growth & development , Male , Sex Factors
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