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1.
J Neuroendocrinol ; 28(2): 12348, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26661058

ABSTRACT

In songbirds and mammals, brain injury results in the up-regulation of aromatase (oestrogen synthase) expression in astroglia. The resulting presumed synthesis of neural oestradiol (E2 ) has neuroprotective effects including a decrease in neurodegeneration, neuroinflammation and apoptosis. The development of therapeutic tools that exploit oestrogenic neuroprotection in the treatment of neurotrauma requires a precise quantification of the endogenous changes in neural aromatase and E2 following brain injury. Surprisingly, the expected increase in neural oestrogens following brain injury has not been demonstrated. Furthermore, we are just beginning to unravel the mechanisms behind the protective effects of centrally synthesised E2 . In the present study, levels of aromatase immunoprotein, neural E2 and steroid receptor mRNA were quantified in adult male and female zebra finches 48 h following a unilateral penetrating brain injury. Both aromatase and E2 were up-regulated in the injured hemisphere of the brain compared to the uninjured hemisphere, demonstrating for the first time a robust increase in neural E2 levels following injury. We did not detect an effect of injury on mRNA expression of the oestrogen receptors (ER)-α, ER-ß or GPER-1, but observed a significant decrease in androgen receptor transcription in the injured lobe relative to the contralateral uninjured hemisphere. We conclude that mechanical damage causes a dramatic increase in local aromatisation, and the resultant high levels of central E2 are available to modulate steroid sensitive targets. Studies using alternate methods of receptor detection and/or time points may be necessary to understand the complete suite of mechanisms underlying the neuroprotective effects of induced oestrogen synthesis in this animal model.


Subject(s)
Aromatase/metabolism , Brain Injuries/metabolism , Estradiol/metabolism , Finches/metabolism , Receptors, Androgen/metabolism , Receptors, Estrogen/metabolism , Animals , Astrocytes/metabolism , Brain Injuries/enzymology , Female , Male , Up-Regulation
2.
J Biol Chem ; 288(48): 34871-81, 2013 Nov 29.
Article in English | MEDLINE | ID: mdl-24121514

ABSTRACT

Cathepsin V is a highly effective elastase and has been implicated in physiological and pathological extracellular matrix degradation. However, its mechanism of action remains elusive. Whereas human cathepsin V exhibits a potent elastolytic activity, the structurally homologous cathepsin L, which shares a 78% amino acid sequence, has only a minimal proteolytic activity toward insoluble elastin. This suggests that there are distinct structural domains that play an important role in elastinolysis. In this study, a total of 11 chimeras of cathepsins V and L were generated to identify elastin-binding domains in cathepsin V. Evaluation of these chimeras revealed two exosites contributing to the elastolytic activity of cathepsin V that are distant from the active cleft of the protease and are located in surface loop regions. Replacement of exosite 1 or 2 with analogous residues from cathepsin L led to a 75 and 43% loss in the elastolytic activity, respectively. Replacement of both exosites yielded a non-elastase variant similar to that of cathepsin L. Identification of these exosites may contribute to the design of inhibitors that will only affect the elastolytic activity of cysteine cathepsins without interfering with other physiological protease functions.


Subject(s)
Cathepsin L/chemistry , Cathepsins/chemistry , Cysteine Endopeptidases/chemistry , Elastin/metabolism , Extracellular Matrix/metabolism , Amino Acid Sequence , Binding Sites , Cathepsin L/metabolism , Cathepsins/isolation & purification , Cathepsins/metabolism , Cysteine Endopeptidases/isolation & purification , Cysteine Endopeptidases/metabolism , Elastin/chemistry , Extracellular Matrix/chemistry , Humans , Macrophages/metabolism , Microscopy, Electron, Scanning , Mutagenesis, Site-Directed , Pancreatic Elastase/chemistry , Pancreatic Elastase/metabolism , Protein Binding , Protein Structure, Secondary , Proteolysis , Structural Homology, Protein , Substrate Specificity
3.
J Microsc ; 226(Pt 1): 6-17, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17381704

ABSTRACT

Fluorescence excitation can result in the formation of reactive oxygen species and free radicals damaging to live cells. In the case of erythrocytes, reaction of these reactive oxygen species with membrane components causes large-scale morphological changes followed by cell haemolysis. In an effort to understand the origin of these morphological changes, we have studied the consequences of localized photodamage on the erythrocyte membrane. For this, we irradiated a small area of the cell membrane using a focused laser beam in the presence of an external photosensitizer. We observed the rapid formation of an invagination (approximately 1 microm deep) at the laser focus, long before photohaemolysis occurred. We measured the rate of invagination formation and the rate of cell haemolysis, using a combination of fluorescence contrast imaging (to detect the membrane position) with fluorescence correlation spectroscopy (to measure photosensitizer concentration). We found that the kinetics of both processes depend in a similar manner on light energy flux, fluorophore concentration and the presence of oxygen scavenger. This leads us to the conclusion that the observed invagination is due to the photooxidation of membrane-associated proteins, representing a precursor of cellular photohaemolysis. We then discuss two different molecular mechanisms (conformational change of the protein band 3 and detachment of the spectrin cytoskeleton from the lipid membrane) that may explain how the photodamage of membrane-associated proteins can lead to a deformation of the lipid bilayer.


Subject(s)
Erythrocyte Membrane/radiation effects , Erythrocytes/cytology , Lasers , Hemolysis , Humans , Image Processing, Computer-Assisted , Microscopy, Fluorescence/methods , Microscopy, Interference/methods , Spectrometry, Fluorescence/methods
5.
J Am Diet Assoc ; 96(8): 771-7, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8683008

ABSTRACT

OBJECTIVE: To assess whether usual diet (especially intake of dietary fat, carbohydrate, and fiber) was related to body fat percentage in healthy men. DESIGN: A written questionnaire provided data on demographic and lifestyle characteristics. Dietary fat, carbohydrate, protein, and fiber intakes were analyzed using the National Cancer Institute food frequency questionnaire. Percentage of body fat was determined using three-site skinfold measurements, and a submaximal treadmill test was used to estimate aerobic fitness. SUBJECTS: Subjects were 203 healthy men (14.0 +/- 5.3% mean body fat) aged 21 to 71 years. The subjects were chosen from randomly selected districts within Utah County and volunteered for free diet and fitness evaluations. STATISTICAL ANALYSIS: Multiple regression analysis determined the extent to which the individual diet components predicted body composition before and after controlling for energy intake, fitness level, body weight, and age. Multivariate analysis of variance was used to compare relative body fat groups in regard to dietary variables. RESULTS: Reported intakes of carbohydrate (P = .0085, R2 = .022), complex carbohydrate (P = .0127, R2 = .024), and fiber (P = .002, R2 = .03) were inversely associated with body fat after controlling for age, energy intake, and fitness level. Energy intake was positively related to body fat after controlling for age, fitness level, and body weight. When subjects were separated into low-, moderate-, and high-body-fat groups, the fattest subjects reported eating significantly more dietary fat (P = .05) and less carbohydrate (P = .01), complex carbohydrate (P = .01), and fiber (P = .005) than the leanest subjects. No significant difference in reported energy intake was noted across body fat groups. APPLICATIONS: Composition of the diet may play a role in obesity beyond energy intake in men over the long-term. Lifestyle changes for men should probably include modifications in diet composition, especially increased consumption of foods high in complex carbohydrate and fiber.


Subject(s)
Adipose Tissue/anatomy & histology , Body Composition , Diet , Adult , Aged , Analysis of Variance , Dietary Carbohydrates/administration & dosage , Dietary Fats/administration & dosage , Dietary Fiber/administration & dosage , Dietary Proteins/administration & dosage , Energy Intake/physiology , Exercise , Humans , Male , Middle Aged , Obesity/etiology , Physical Fitness , Regression Analysis , Skinfold Thickness , Surveys and Questionnaires , Utah
7.
Int J Gynaecol Obstet ; 52(2): 141-4, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8855092

ABSTRACT

OBJECTIVE: To evaluate the perinatal morbidity and mortality of fetuses diagnosed with gastroschisis at our Fetal Diagnosis and Treatment Center. METHODS: A retrospective review of a regional prenatal diagnostic center. Twenty-nine cases of gastroschisis which were diagnosed, managed, delivered and had corrective surgeries through the Fetal Diagnosis and Treatment Center were identified from 1985 to 1994. Perinatal morbidity and mortality were reviewed. Antepartum testing schemes were reviewed when available to determine whether morbidity or mortality could have potentially been prevented. RESULTS: Meconium occurrence, intrauterine growth retardation (IUGR) and oligohydramnios complicated 79%, 41% and 36% of the cases, respectively. The perinatal mortality of this series was 241/1000. Significant differences in perinatal mortality were noted when fetal testing was incorporated (200/1000 vs. 286/1000, P < or = 0.001). CONCLUSION: Gastroschisis is associated with a high incidence of IUGR, meconium, oligohydramnios and high perinatal mortality. Antenatal testing appears to significantly lower perinatal mortality in pregnancies complicated by gastroschisis.


Subject(s)
Abdominal Muscles/abnormalities , Fetal Death/epidemiology , Fetal Diseases/prevention & control , Fetal Monitoring , Female , Fetal Growth Retardation/epidemiology , Humans , Meconium/metabolism , Oligohydramnios/epidemiology , Pregnancy , Retrospective Studies , alpha-Fetoproteins/analysis
8.
Pediatr Neurosurg ; 24(3): 134-7; discussion 138, 1996.
Article in English | MEDLINE | ID: mdl-8870016

ABSTRACT

Advances in realtime ultrasound imaging and a greater availability of high-quality ultrasound equipment have resulted in an increased number of congenital abnormalities being diagnosed prenatally in the last 10-15 years. In addition, testing for maternal serum alpha-fetoprotein, beta-human chorionic gonadotropin, and serum unconjugated estriol has allowed for more sensitive screening for congenital abnormalities. In response to this, in 1989 the Prenatal Diagnosis and Treatment Center was established at our institution to coordinate the care of fetuses and newborns with congenital malformations and to provide alternatives for the parents should the fetus not be carried to term. From January 1990 through June 1993, our group diagnosed 50 singleton pregnancies with various types of central nervous system disorders by the methods outlined above. Thirty-seven fetuses were diagnosed with neural tube defects. Of these, 5 were anencephalic and 1 had an encephalocele. The remaining 31 fetuses had meningomyeloceles with associated hydrocephalus. Of these 31, 18 fetuses were terminated prior to the age of viability as a result of our counseling and 13 fetuses were brought to term. Of the remaining 13 fetuses, 8 had hydrocephalus and 5 had various other diagnoses. Three of the eight hydrocephalic fetuses were either terminated, stillborn, or died following birth. Of the other 5 fetuses with hydrocephalus, 3 had shunts placed, 1 was followed with normal head growth, and 1 had normal ventricular size at birth. Using the methods available, the accuracy of diagnosis is very high, with only 1 fetus in this series being incorrectly diagnosed. Additionally the advantages of being able to counsel the parents regarding their unborn child allows them to make informed decisions. Accurate prenatal diagnosis plays a major role in the care of the fetus and in counseling parents prenatally for pediatric neurosurgical problems.


Subject(s)
Central Nervous System/abnormalities , Hydrocephalus/diagnostic imaging , Neural Tube Defects/diagnostic imaging , Ultrasonography, Prenatal , Abnormalities, Multiple/diagnostic imaging , Abnormalities, Multiple/surgery , Abortion, Eugenic , Amniocentesis , Central Nervous System/diagnostic imaging , Central Nervous System/surgery , Cerebrospinal Fluid Shunts , Female , Humans , Hydrocephalus/surgery , Infant , Infant, Newborn , Meningomyelocele/diagnostic imaging , Meningomyelocele/surgery , Neural Tube Defects/surgery , Patient Care Team , Pregnancy , Prognosis , Treatment Outcome , alpha-Fetoproteins/analysis
9.
Am J Obstet Gynecol ; 171(2): 350-6; discussion 356-8, 1994 Aug.
Article in English | MEDLINE | ID: mdl-8059812

ABSTRACT

OBJECTIVES: Our purpose was to (1) evaluate expectant management of preterm premature rupture of the membranes between 20 and < 36 weeks' gestation and (2) compare outcomes in service and private populations. STUDY DESIGN: The study included only singleton pregnancies prospectively managed between 20 and < 36 weeks' gestation with proved preterm premature rupture of the membranes. None of the patients received prophylactic antibiotics, tocolytics, or steroids, and none of the neonates received surfactant or had lethal anomalies. Patients (n = 511) were divided into private (n = 194) and staff (n = 317) categories, but all were managed identically. RESULTS: Approximately 50% of patients were delivered within 48 hours. Infection is more likely with preterm premature rupture of membranes before 28 weeks' gestation (p = 0.001), as is fetal death associated with infection (p < 0.001). Other findings in this study were (1) no significant differences in evaluated outcomes between private and staff patients, except that significantly more vaginal deliveries occurred in staff patients, (2) a prolongation of pregnancy > or = 7 days in 12.9% of patients, (3) a significant increase in the rate of maternal infection if preterm rupture of membranes occurred before 28 weeks' gestation, (4) a significant increase in fetal and neonatal deaths if preterm premature rupture of membranes occurred before 28 weeks, and (5) an increased probability of survival whose rate of increase is dependent on the gestational age at which preterm premature rupture of membranes occurred. For babies weighing < 1500 gm at birth compared with controls, babies delivered of mothers not having preterm premature rupture of membranes, 1-year follow-up revealed (1) a significantly lower incidence of pulmonary interstitial emphysema and cerebral palsy in the study group delivered before 28 weeks' gestation, (2) a significantly lower incidence in bronchopulmonary dysplasia in the study group delivered after 28 weeks' gestation, and (3) no significant differences in the incidence of intraventricular hemorrhage, pneumothorax, or Bayley Mental Developmental Index < 68 between those delivered before or after 28 weeks' gestation. CONCLUSION: Over 47.8% of the patients continued their pregnancy beyond 48 hours, and in 12.9% of cases expectant management of preterm premature rupture of membranes prolonged the pregnancy by > or = 7 days. The maternal infection rate is greater before 28 weeks' gestation and is associated with higher fetal-neonatal mortality. Status has little impact on outcome. Expectant management is not detrimental to quality of survival. Survival probability increases at a more rapid rate with preterm premature rupture of membranes after 22 weeks of gestation.


Subject(s)
Fetal Membranes, Premature Rupture/therapy , Obstetric Labor, Premature/therapy , Adult , Child Development , Female , Follow-Up Studies , Humans , Incidence , Infant Mortality , Infant, Newborn , Infant, Newborn, Diseases/epidemiology , Infant, Premature , Insurance, Health , Logistic Models , Male , Pregnancy , Survival Analysis
12.
J Reprod Med ; 38(4): 311-3, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8501742

ABSTRACT

The obstetric and anesthetic considerations in the management of a patient with the May-Hegglin anomaly, an autosomal dominant platelet deficiency, are discussed. A review of the medical literature notes three previous case reports of May-Hegglin anomaly in pregnancy. In addition to the two successful pregnancies reported in this paper, there are four infant survivors among the five reported pregnancies. Anesthetic managements included general and spinal anesthesia: the latter employed following platelet transfusion. A successful pregnancy should be anticipated when management includes a well-informed patient and coordinated obstetric and anesthetic care.


Subject(s)
Anesthesia, Obstetrical/methods , Cesarean Section , Pregnancy Complications, Hematologic , Thrombocytopenia/genetics , Adult , Female , Humans , Pregnancy
14.
Am J Med Genet ; 41(4): 426-31, 1991 Dec 15.
Article in English | MEDLINE | ID: mdl-1776631

ABSTRACT

Two pregnancies in a 25-year-old woman with hereditary orotic aciduria who was managed prenatally on uridine therapy are described. The first pregnancy resulted in an infant with multiple congenital anomalies and a 47,xx,inv(4)(p12q25), +der(22)t(11;22)(p23;q11) karyotype. The proposita was found to be a carrier of a de novo 11;22 translocation and a pericentric inversion of chromosome 4. Subsequently, several carriers of orotic aciduria in this family were identified with the inverted chromosome 4. The second pregnancy resulted in a normal male with an inverted chromosome 4.


Subject(s)
Orotic Acid/urine , Pregnancy Complications/urine , Abnormalities, Multiple/genetics , Adult , Chromosome Aberrations , Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 22 , Chromosomes, Human, Pair 5 , Female , Genes, Recessive , Humans , Infant , Infant, Newborn , Male , Multienzyme Complexes/deficiency , Orotate Phosphoribosyltransferase/deficiency , Orotidine-5'-Phosphate Decarboxylase/deficiency , Pedigree , Pregnancy , Translocation, Genetic
15.
Obstet Gynecol Clin North Am ; 18(4): 683-92, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1803297

ABSTRACT

Transvaginal sonography provides improved resolution and avoidance of intervening anatomic structures that can degrade the image. In this article, transvaginal transducers are described and compared with transabdominal transducers. The sagittal and coronal views used in transvaginal sonography are described. Advantages and disadvantages of transvaginal sonography are considered. Safety considerations of the decreased attenuation path to the fetus are dealt with.


Subject(s)
Genitalia, Female/diagnostic imaging , Ultrasonography, Prenatal/methods , Abdomen , Female , Humans , Image Enhancement , Pregnancy , Transducers , Ultrasonography, Prenatal/instrumentation , Vagina
16.
Obstet Gynecol ; 76(3 Pt 2): 506-9, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2199872

ABSTRACT

Vasa previa, which is associated with high fetal mortality, is present when fetal vessels cross the internal cervical os as a velamentous insertion of the umbilical cord with or without a succenturiate lobe or bilobate placenta. This is the first case report of vasa previa not associated with a succenturiate lobe or bilobate placenta and in which the diagnosis was made using a combination of transvaginal ultrasonography and color flow Doppler ultrasound. The infant was delivered by elective cesarean, and the ultrasound findings were confirmed. Color flow Doppler and transvaginal ultrasound facilitate this diagnosis because the internal os and surrounding structures are easier to visualize; in addition, vascular flow and Doppler patterns characteristic of the umbilical cord can be demonstrated in structures suspected to be vessels.


Subject(s)
Prenatal Diagnosis/methods , Ultrasonography/methods , Umbilical Arteries/abnormalities , Umbilical Veins/abnormalities , Adult , Diagnosis, Differential , Female , Humans , Male , Placenta Previa/diagnosis , Pregnancy , Vagina
17.
South Med J ; 83(2): 150-5, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2406930

ABSTRACT

Using continuous wave Doppler ultrasound, we studied the umbilical and uterine flow velocity waveforms in 68 pregnant women who had chronic hypertension and/or preeclampsia. The systolic-diastolic (S/D) ratio was considered an expression of vascular resistance peripheral to the point of insonation. Abnormal umbilical artery S/D ratio (greater than 95th percentile) alone or with abnormal uterine artery S/D ratio was associated with poor pregnancy outcome as judged by incidence of intrauterine growth retardation (IUGR), cesarean section rate, birth weight, perinatal morbidity and mortality, and prematurity. In patients with preeclampsia and abnormal Doppler values, pregnancy outcome was poor, whereas in those with normal Doppler values, pregnancy outcome approached normal. The same relationship was also found in patients with chronic hypertension. The sensitivity and specificity for the prediction of IUGR by the umbilical artery S/D ratio alone was 71% and 93%, respectively. The uterine artery S/D ratio alone yielded a 66% sensitivity and 64% specificity, and when both tests were taken into account, the sensitivity increased to 75% and the specificity to 100%. Abnormal umbilical and uterine artery S/D ratios were associated with 100% IUGR and 25% perinatal mortality. We conclude that in pregnant women with hypertensive disorders there is a significant difference in pregnancy outcome between those with normal and those with abnormal Doppler values. Umbilical artery S/D ratio alone is a better predictor of IUGR and poor pregnancy outcome than the uterine artery S/D ratio.


Subject(s)
Hypertension/physiopathology , Pre-Eclampsia/physiopathology , Pregnancy Complications, Cardiovascular/physiopathology , Ultrasonography/methods , Umbilical Arteries/physiology , Uterus/blood supply , Blood Flow Velocity/physiology , Chronic Disease , Evaluation Studies as Topic , Female , Fetal Growth Retardation/diagnosis , Fetal Growth Retardation/physiopathology , Humans , Hypertension/complications , Infant, Newborn , Pre-Eclampsia/complications , Predictive Value of Tests , Pregnancy , Prognosis , Severity of Illness Index , Vascular Resistance/physiology
19.
Obstet Gynecol ; 74(4): 607-10, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2797638

ABSTRACT

Among 93 acetylcholinesterase determinations performed on amniotic fluid samples from pregnancies at 11-14 weeks' gestation, five unexplained false-positive results were observed. In four of the five cases, the ratio of acetylcholinesterase to pseudocholinesterase was compatible with that observed in association with open neural tube defects in later gestation. In contrast, no false-positive results were noted among 951 acetylcholinesterase determinations performed on samples from women at 15-20 weeks' gestation. Repeat amniocentesis was performed several weeks after the first procedure in four of the five cases of early amniocentesis and false-positive results; in each case, the acetylcholinesterase was negative on the second sample. All four pregnancies had a normal outcome. In the remaining case, trisomy 21 was diagnosed in the fetus and the pregnancy was terminated. Positive acetylcholinesterase results should be interpreted cautiously in samples from early amniocentesis, especially when the amniotic fluid alpha-fetoprotein level is not markedly elevated. The acetylcholinesterase-to-pseudocholinesterase ratio is not useful in identifying fetal neural tube defects before 15 weeks' gestation. Repeat amniocentesis may help in determining the significance of a positive acetylcholinesterase result from early amniocentesis when no fetal defect is identified by ultrasonography.


Subject(s)
Acetylcholinesterase/analysis , Amniocentesis , Amniotic Fluid/analysis , Clinical Enzyme Tests , Neural Tube Defects/diagnosis , False Positive Reactions , Female , Humans , Pregnancy , Pregnancy Trimester, First , Pregnancy Trimester, Second , Prenatal Diagnosis
20.
Am J Obstet Gynecol ; 160(3): 704-7, 1989 Mar.
Article in English | MEDLINE | ID: mdl-2929696

ABSTRACT

We prospectively examined 55 normal pregnant women between 32 and 41 (means = 37) weeks' gestation. Five measurements of the umbilical artery peak-systolic/end-diastolic frequency ratio were obtained from each patient during one examination. Comparison of the fetal heart rate and the umbilical artery peak-systolic/end-diastolic frequency ratios between pregnancies less than 37 and greater than 37 weeks' gestation revealed no difference. Subsequently a total of 256 measurements were analyzed as one group. Plotting the individual peak-systolic/end-diastolic frequency ratios against the corresponding fetal heart rates revealed a moderate negative linear correlation: y = 4.15-0.012x, r = -0.36 and p less than 0.04. When only heart rates between 120 to 160 beats/min were plotted against peak-systolic/end-diastolic frequency ratios, a weaker correlation was found (r = -0.33, p = 0.15). The difference (mean +/- SD) between the obtained and the corrected peak-systolic/end-diastolic frequency ratios was 4.4% +/- 3.2%. The 95th percentile of the obtained peak-systolic/end-diastolic frequency ratio was 3.35 and the corrected ratio was 3.27. Averaging of the five measurements obtained from each patient for all 55 patients decreased the 95th percentile value to 3.09 whereas the same procedure for the corrected peak-systolic/end-diastolic frequency ratios decreased it to 3.07. We conclude that although there is a statistically significant negative linear correlation between the fetal heart rate and the umbilical artery peak-systolic/end-diastolic frequency ratio, this relationship is not clinically significant.


Subject(s)
Fetal Heart , Heart Rate , Umbilical Cord/blood supply , Arteries , Blood Flow Velocity , Diastole , Female , Humans , Pregnancy , Prospective Studies , Regression Analysis , Systole
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