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2.
Ultrasound Obstet Gynecol ; 58(6): 882-891, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33998089

RESUMO

OBJECTIVE: We have shown previously that third-trimester growth in small fetuses (estimated fetal weight (EFW) < 10th percentile) with birth weight (BW) < 10th percentile is heterogeneous using individualized growth assessment (IGA). We aimed to test our hypothesis that individual growth patterns in small fetuses with BW > 10th percentile are also variable but in different ways. METHODS: This was a study of 191 cases with EFW < 10th percentile and BW > 10th percentile (appropriate-for-gestational-age (AGA) cohort), derived from the PORTO study. Composite size parameters were used to quantify growth pathology at individual third-trimester timepoints (individual composite prenatal growth assessment score (-icPGAS)). The fetal growth pathology score 1 (-FGPS1), calculated cumulatively from serial -icPGAS values, was used to characterize third-trimester growth patterns. Vascular-system evaluation included umbilical artery (UA) and middle cerebral artery (MCA) Doppler velocimetry. Outcome variables were birth age (preterm/term delivery) and BW (expressed as growth potential realization index for weight (GPRIWT ) and percentile). The findings from the AGA cohort were compared with those from small fetuses (EFW < 10th percentile) with BW < 10th percentile (small-for-gestational-age (SGA) cohort). RESULTS: The AGA cohort was found to have 134 fetuses (70%) with normal growth pattern and 57 (30%) with growth restriction based on IGA criteria. Seven growth-restriction -FGPS1 patterns were observed, including the previously defined progressive, late, adaptive and recovering types. The recovering type was the most common growth pattern in the AGA cohort (50.9%). About one-third of fetuses without any evidence of growth restriction had significant unexplained abnormalities in the UA (34%) and MCA (31%) and elevated mean GPRIWT values (113 ± 12.5%). Comparison of the AGA and SGA cohorts indicated a significant difference in the distribution of -FGPS1 growth patterns (P = 0.0001). Compared with the SGA cohort, the AGA cohort had more fetuses with a normal growth pattern (70% vs 38%) and fewer cases with growth restriction (30% vs 62%). While the recovering type was the most common growth-restriction pattern in the AGA cohort (51%), the progressive type was the primary growth-restriction pattern in the SGA cohort (44%). No difference in the incidence of MCA or UA abnormality was found between the SGA and AGA cohorts when comparing subgroups of more than 10 fetuses. CONCLUSIONS: Both normal-growth and growth-restriction patterns were observed in the AGA cohort using IGA, as seen previously in the SGA cohort. The seven types of growth restriction defined in the SGA cohort were also identified in AGA cases, but their distribution was significantly different. In one-third of cases without evidence of growth pathology in the AGA cohort, Doppler abnormalities in the UA and MCA were seen. This heterogeneity underscores the difficulty of accurate classification of fetal and neonatal growth status using conventional population-based methods. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Desenvolvimento Fetal/fisiologia , Retardo do Crescimento Fetal/diagnóstico por imagem , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Ultrassonografia Doppler/estatística & dados numéricos , Ultrassonografia Pré-Natal/estatística & dados numéricos , Adulto , Peso ao Nascer/fisiologia , Feminino , Retardo do Crescimento Fetal/fisiopatologia , Peso Fetal/fisiologia , Idade Gestacional , Humanos , Recém-Nascido , Estudos Longitudinais , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/embriologia , Gravidez , Terceiro Trimestre da Gravidez , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/embriologia
3.
Ultrasound Obstet Gynecol ; 54(3): 338-343, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30887629

RESUMO

OBJECTIVE: Increased fetal size is associated with shoulder dystocia during labor and subsequent need for assisted delivery. We sought to investigate if increased fetal adiposity diagnosed sonographically in late pregnancy is associated with increased risk of operative delivery. METHODS: This secondary analysis of the Genesis Study recruited 2392 nulliparous women with singleton pregnancy in cephalic presentation, in a prospective, multicenter study, to examine prenatal and intrapartum predictors of Cesarean delivery. Participants underwent ultrasound and clinical evaluation between 39 + 0 and 40 + 6 weeks' gestation. Data on fetal biometry were not revealed to patients or to their managing clinicians. A fetal adiposity composite of fetal thigh adiposity and fetal abdominal wall thickness was compiled for each infant in order to determine whether fetal adiposity > 90th centile was associated with an increased risk of Cesarean or operative vaginal delivery. RESULTS: After exclusions, data were available for 2330 patients. Patients with a fetal adiposity composite > 90th centile had a higher maternal body mass index (BMI) (25 ± 5 kg/m2 vs 24 ± 4 kg/m2 ; P = 0.005), birth weight (3872 ± 417 g vs 3585 ± 401 g; P < 0.0001) and rate of induction of labor (47% (108/232) vs 40% (834/2098); P = 0.048) than did those with an adiposity composite ≤ 90th centile. Fetuses with adiposity composite > 90th centile were more likely to require Cesarean delivery than were those with adiposity composite ≤ 90th centile (P < 0.0001). After adjusting for birth weight, maternal BMI and need for induction of labor, fetal adiposity > 90th centile remained a risk factor for Cesarean delivery (P < 0.0001). A fetal adiposity composite > 90th centile was more predictive of the need for unplanned Cesarean delivery than was an estimated fetal weight > 90th centile (odds ratio, 2.20 (95% CI, 1.65-2.94; P < 0.001) vs 1.74 (95% CI, 1.29-2.35; P < 0.001). Having an adiposity composite > 90th centile was not associated with an increased likelihood of operative vaginal delivery when compared with having an adiposity composite ≤ 90th centile (P = 0.37). CONCLUSIONS: Fetuses with increased adipose deposition are more likely to require Cesarean delivery than are those without increased adiposity. Consideration should, therefore, be given to adding fetal thigh adiposity and abdominal wall thickness to fetal sonographic assessment in late pregnancy. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Cesárea/estatística & dados numéricos , Macrossomia Fetal/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Feminino , Peso Fetal , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Medição de Risco
4.
Br J Anaesth ; 118(4): 527-532, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28403411

RESUMO

BACKGROUND.: Non-invasive cardiac output monitoring (NICOM) using bioreactance (BRT) in pregnancy is gaining interest but lacks validation. We compared simultaneous cardiac output (CO) measurements obtained using the NICOM ® (BRT-CO) and echocardiography (echo-CO), and assessed the relationship between maternal characteristics and myocardial performance. METHODS.: Paired stroke volume (SV) and CO readings were obtained using NICOM ® and echocardiography, in a group of healthy nulliparous women throughout a 15 min period. Agreement between NICOM ® and echocardiography was assessed using Bland-Altman analysis and the intraclass correlation coefficient (ICC). Left ventricular (LV) function was assessed using systolic strain and tissue Doppler velocities (S', E', and A' waves). RESULTS.: Thirty-five women with a median [interquartile range] age, weight, and gestation of 29 [26-34] yr, 71 [64-79] kg, and 28 [21-29] weeks, respectively, were enrolled. There was good agreement between NICOM ® -measured and echocardiographically measured SV [mean bias 6 ml (limits of agreement -18 to 29); ICC 0.8 (95% confidence interval 0.6-0.9), P <0.001] and CO [mean bias 0.2 litres (limits of agreement -1.3-1.7); ICC 0.8 (95% confidence interval 0.7-0.9), P <0.001; mean percentage error ±26%; coefficient of error (precision)=3.4%]. The mean ( sd ) LV S' was 9.7 (2.3) cm s -1 . The mean ( sd ) LV strain was -18.6 (2.6)%. There was a negative relationship between BMI and LV diastolic function measured using the E':A' ratio ( r = -0.51, P <0.01). CONCLUSIONS.: Stroke volume and CO measurements obtained using NICOM ® were comparable to those obtained using echocardiography, with acceptable limits of agreement. Increased maternal BMI negatively impacts LV diastolic function measured using tissue Doppler imaging.


Assuntos
Débito Cardíaco , Ecocardiografia/métodos , Testes de Função Cardíaca , Monitorização Intraoperatória/métodos , Paridade , Adulto , Estudos Transversais , Feminino , Humanos , Gravidez , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem
5.
Eur J Pain ; 19(8): 1177-85, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25504741

RESUMO

BACKGROUND: Distraction is used clinically to relieve and manage pain. It is hypothesized that pain demands attention and that exposure to another attention-demanding stimulus causes withdrawal of attention away from painful stimuli, thereby reducing perceived pain. We have recently developed a rat model that provides an opportunity to investigate the neurobiological mechanisms mediating distraction-induced analgesia, as these mechanisms are, at present, poorly understood. Given the well-described role of the endogenous cannabinoid (endocannabinoid; EC) system in the modulation of pain and attentional processing, the present study investigated its role in distraction-induced antinociception in rats. METHODS: Animals received the CB1 receptor antagonist/inverse agonist, rimonabant or vehicle intraperitoneally, 30 min prior to behavioural evaluation. Formalin-evoked nociceptive behaviour was measured in the presence or absence of a novel-object distractor. Liquid chromatography-tandem mass spectrometry was used to determine the levels of the endogenous cannabinoids anandamide and 2-arachidonoylglycerol (2-AG) in the ventral hippocampus (vHip). RESULTS: Exposure to a novel object distractor significantly reduced formalin-evoked nociceptive behaviour. The novel object-induced reduction in nociceptive behaviour was attenuated by rimonabant. Novel object exposure was also associated with increased tissue levels of anandamide and 2-AG in the vHip. CONCLUSIONS: These data suggest that the reduction in formalin-evoked nociceptive behaviour that occurs as a result of exposure to a novel object may be mediated by engagement of the EC system, in particular in the vHip. The results provide evidence that the EC system may be an important neural substrate subserving attentional modulation of pain.


Assuntos
Atenção , Comportamento Animal , Antagonistas de Receptores de Canabinoides/farmacologia , Endocanabinoides , Nociceptividade , Dor/fisiopatologia , Dor/psicologia , Piperidinas/farmacologia , Pirazóis/farmacologia , Animais , Ácidos Araquidônicos/metabolismo , Endocanabinoides/metabolismo , Comportamento Exploratório/efeitos dos fármacos , Medo/psicologia , Glicerídeos/metabolismo , Hipocampo/química , Hipocampo/metabolismo , Masculino , Medição da Dor , Alcamidas Poli-Insaturadas/metabolismo , Ratos , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Rimonabanto
6.
Ultrasound Obstet Gynecol ; 44(4): 461-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24407772

RESUMO

OBJECTIVE: To construct monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin reference ranges for umbilical artery (UA) pulsatility index (PI), UA resistance index (RI), fetal middle cerebral artery (MCA) PI and peak systolic velocity (PSV) and cerebroplacental ratio (CPR) from 24 weeks' to 38 weeks' gestation and compare these with published normal values for singleton pregnancies. METHODS: This prospective multicenter cohort study included 1028 unselected twin pairs recruited over a 2-year period. Participants with dichorionic twins underwent fortnightly ultrasound surveillance from 24 weeks' gestation, with monochorionic twins being followed every 2 weeks from 16 weeks until delivery. A total of 7536 fetal Doppler examinations in 618 twin pregnancies were included in the analysis, with reference ranges for MCDA and DCDA pregnancies constructed for each of the Doppler indices using multilevel modeling. RESULTS: UA-PI and UA-RI appear to be higher in twins than in singletons, and MCA-PI and MCA-PSV appear to be lower. The CPR also appears to be lower in twins than in singletons. Similar MCA indices were observed in MCDA and DCDA twins. CONCLUSION: We have established longitudinal reference ranges for UA-PI and UA-RI, MCA-PI and MCA-PSV and CPR in twin pregnancies, which appear to differ from those in singleton pregnancies. The derived twin-specific reference ranges may be more appropriate in the surveillance of these high-risk pregnancies. Applying the singleton CPR cut-off of ≤ 1.0 may lead to a large number of false-positive diagnoses of cerebral redistribution in twin fetuses.


Assuntos
Artéria Cerebral Média/diagnóstico por imagem , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Artérias Umbilicais/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Feto/irrigação sanguínea , Idade Gestacional , Humanos , Estudos Longitudinais , Gravidez , Gravidez de Alto Risco , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência , Ultrassonografia Pré-Natal
7.
Skeletal Radiol ; 36(8): 761-7, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17437103

RESUMO

OBJECTIVE: Several measures can quantify thoracic kyphosis from radiographs, yet their suitability for people with osteoporosis remains uncertain. The aim of this study was to examine the validity and reliability of the vertebral centroid and Cobb angles in people with osteoporosis. DESIGN AND PATIENTS: Lateral radiographs of the thoracic spine were captured in 31 elderly women with osteoporosis. Thoracic kyphosis was measured globally (T1-T12) and regionally (T4-T9) using Cobb and vertebral centroid angles. Multisegmental curvature was also measured by fitting polynomial functions to the thoracic curvature profile. Canonical and Pearson correlations were used to examine correspondence; agreement between measures was examined with linear regression. RESULTS: Moderate to high intra- and inter-rater reliability was achieved (SEM = 0.9-4.0 degrees ). Concurrent validity of the simple measures was established against multisegmental curvature (r = 0.88-0.98). Strong association was observed between the Cobb and centroid angles globally (r = 0.84) and regionally (r = 0.83). Correspondence between measures was moderate for the Cobb method r = 0.72), yet stronger for the centroid method (r = 0.80). The Cobb angle was 20% greater for regional measures due to the influence of endplate tilt. CONCLUSIONS: Regional Cobb and centroid angles are valid and reliable measures of thoracic kyphosis in people with osteoporosis. However, the Cobb angle is biased by endplate tilt, suggesting that the centroid angle is more appropriate for this population.


Assuntos
Cifose/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Interpretação Estatística de Dados , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Cifose/etiologia , Pessoa de Meia-Idade , Variações Dependentes do Observador , Osteoporose/complicações , Radiografia , Reprodutibilidade dos Testes , Fraturas da Coluna Vertebral/etiologia , Vértebras Torácicas/lesões
8.
Man Ther ; 6(4): 213-20, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11673931

RESUMO

The usual activity level and history of low back pain was determined by questionnaire in 614 young Australians (9-27 years); dancers (25%), gymnasts (5%) and a control group who did not participate in dance or gymnastics for > or =6 hours/week during the previous three months (70%). These groups demonstrated significantly different activity levels (dancers >gymnasts >controls). Of all respondents, 34% experienced pain of more than two days duration in the previous year, and 50% in all previous years. The incidence and magnitude of pain in the previous year was significantly greater in the dancers and gymnasts (P<0.05) compared to the controls. The incidence of pain was not linked to the average total hours of activity until this exceeded 30 hours per week. There was no significant difference in the incidence of pain in the previous year between control group respondents who did and did not undertake regular activity. The average hours of activity per incident was approximately 20 hours for the dancers and approximately 5 hours for the other groups. This study has demonstrated that back pain in active and inactive adolescents presents a significant challenge for health-care practitioners involved in the management and prevention of symptomatic spinal disorders.


Assuntos
Dança , Ginástica , Dor Lombar/etiologia , Dor Lombar/terapia , Adolescente , Adulto , Análise de Variância , Austrália/epidemiologia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Incidência , Dor Lombar/epidemiologia , Masculino , Medição da Dor/métodos , Análise de Regressão , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Fatores de Tempo
9.
Arch Phys Med Rehabil ; 78(7): 759-66, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9228881

RESUMO

OBJECTIVE: Despite widespread use of the toe touch test, the relative contribution from vertebral and hip movements has not been clearly established, largely because of unsatisfactory measurement techniques. This study aimed to reinvestigate the kinematics of toe touching by combining computerized videotape analysis with a new model of reference marker placement. METHOD: Twenty-two subjects were videotaped during active toe touching from upright standing. Computer software was then used to derive the sagittal thoracic, lumbar, and hip angles at .02-sec intervals throughout the movement. RESULTS: Hip flexion was directly proportional to toe touch distance (TTD) (r2 = .71) but not lumbar flexion (r2 = .17) or thoracic (r2 = .20) excursion. On average there was .8 degree of thoracolumbar flexion for every 1 degree of hip flexion; however, there were wide variations between subjects. In 19 of 22 subjects the thoracic spine flexed and extended relatively equal amounts during the test resulting in a small total thoracic excursion of 4.8 degrees flexion in unsuccessful toe touchers and 4.0 degrees extension in successful toe touchers. CONCLUSION: The separate contributions of hip, lumbar, and thoracic mobility to toe touching or any other vertebrofemoral motion can only be accurately determined by a measurement strategy that uses the plane of the pelvis to separate vertebral from hip motion and uses tangents at the limits of the thoracic and lumbar regions to separate lumbar from thoracic motion. Using this model the authors found that TTD is not a reliable indicator of either vertebral or hip mobility.


Assuntos
Antropometria/métodos , Fêmur/fisiologia , Amplitude de Movimento Articular , Processamento de Sinais Assistido por Computador , Coluna Vertebral/fisiologia , Gravação de Videoteipe , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Dedos do Pé
10.
Prehosp Disaster Med ; 10(4): 239-44, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-10172477

RESUMO

INTRODUCTION: Awareness of the risk of spinal-cord damage in moving an unconscious person with a suspected neck injury into the "lateral recovery position," coupled with the even greater risk of inadequate airway management if the person is not moved, has resulted in a suggested modification to the lateral recovery position for use in this circumstance. HYPOTHESIS: It is proposed that the modification to the lateral recovery position reduces movement of the neck. In this modification, one of the patient's arms is raised above the head (in full abduction) to support the head and neck. The position is called the "HAINES modified recovery position." HAINES is an acronym for High Arm IN Endangered Spine. METHODS: Neck movements in two healthy volunteers were measured by the use of video-image analysis and radiographic studies when the volunteers were rolled from the supine position to both the lateral recovery position and the HAINES modified recovery position. RESULTS: For both subjects, the total degree of lateral flexion of the cervical spine in the HAINES modified recovery position was less than half of that measured during use of the lateral recovery position (while an open airway was maintained in each). CONCLUSION: An unconscious person with a suspected neck injury should be positioned in the HAINES modified recovery position. There is less neck movement (and less degree of lateral angulation) than when the lateral recovery position is used, and, therefore, HAINES use carries less risk of spinal-cord damage.


Assuntos
Coma/complicações , Serviços Médicos de Emergência/métodos , Lesões do Pescoço , Postura , Adulto , Eletromiografia , Humanos , Masculino , Radiografia , Amplitude de Movimento Articular , Gravação de Videoteipe , Ferimentos e Lesões/complicações , Ferimentos e Lesões/diagnóstico por imagem , Ferimentos e Lesões/fisiopatologia , Ferimentos e Lesões/terapia
12.
South Med J ; 84(3): 323-7, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2000518

RESUMO

Mental illness can devastate persons intellectually and emotionally; with maintenance therapy, however, certain patients with chronic mental illnesses are capable of holding a variety of jobs. From the total population of psychiatric patients in our VA outpatient clinic, the 87 who were gainfully employed were identified to determine common factors among them. Affective disorders were the predominant diagnoses among patients who worked, while schizophrenia was more common among those who did not. Alcoholism was diagnosed in approximately 25% of working and nonworking groups.


Assuntos
Emprego , Transtornos Mentais/reabilitação , Adulto , Transtornos Psicóticos Afetivos/complicações , Transtornos Psicóticos Afetivos/tratamento farmacológico , Transtornos Psicóticos Afetivos/reabilitação , Alcoolismo/complicações , Alcoolismo/reabilitação , Doença Crônica , Características da Família , Feminino , Humanos , Masculino , Transtornos Mentais/tratamento farmacológico , Pessoa de Meia-Idade , Transtornos do Humor/complicações , Transtornos do Humor/tratamento farmacológico , Transtornos do Humor/reabilitação , Ocupações , Estudos Retrospectivos , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico , Esquizofrenia/reabilitação , Apoio Social , Estados Unidos , Veteranos
14.
Adv Exp Med Biol ; 165 Pt B: 419-24, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6720439

RESUMO

Electrical stimulation, as anticipated brought about a fall in total ATP. Despite this there was little extra utilization of [8-14C]adenine to replace the ATP lost. The results suggest that allopurinol increased [8-14C]adenine utilization in both resting and stimulated muscle and, in particular, increased incorporation into ATP. After 30 minutes recovery total ATP levels had not returned to control resting values. [8-14C]adenine utilization, however, was markedly increased with most of the label incorporated into ATP. The results again suggest that addition of allopurinol to the medium increased [8-14C] adenine utilization of the label by recovering muscle.


Assuntos
Adenina/metabolismo , Músculos/metabolismo , Trifosfato de Adenosina/metabolismo , Alopurinol/farmacologia , Animais , Estimulação Elétrica , Hipoxantina , Hipoxantinas/metabolismo , Contração Muscular , Músculos/efeitos dos fármacos , Ratos
15.
Biochem J ; 216(3): 605-10, 1983 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-6421275

RESUMO

Purine biosynthesis by the 'de novo' pathway was demonstrated in isolated rat extensor digitorum longus muscle with [1-14C]glycine, [3-14C]serine and sodium [14C]formate as nucleotide precursors. Evidence is presented which suggests that the source of glycine and serine for purine biosynthesis is extracellular rather than intracellular. The relative incorporation rates of the three precursors were formate greater than glycine greater than serine. Over 85% of the label from formate and glycine was recovered in the adenine nucleotides, principally ATP. Azaserine markedly inhibited purine biosynthesis from both formate and glycine. Cycloserine inhibited synthesis from serine, but not from formate. Adenine, hypoxanthine and adenosine markedly inhibited purine synthesis from sodium [14C]formate.


Assuntos
Músculos/metabolismo , Purinas/biossíntese , Adenina/farmacologia , Adenosina/farmacologia , Animais , Azasserina/farmacologia , Ciclosserina/farmacologia , Feminino , Formiatos/metabolismo , Glicina/metabolismo , Hipoxantina , Hipoxantinas/farmacologia , Técnicas In Vitro , Masculino , Músculos/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Serina/metabolismo
17.
Adv Exp Med Biol ; 122B: 13-7, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-546140

RESUMO

1. Rat skeletal muscle can synthesize purine nucleotides de novo. 2. Nucleotide synthesis de novo was inhibited by approximately 90% in the presence of 1 mM azaserine. 3. Purine nucleotides can be synthesized via "salvage" pathways from purine bases and nucleosides. Under the conditions employed incorporation rates were adenosine adenine inosine/hypoxanthine guanosine guanine. 4. Xanthine was not utilized for nucleotide synthesis.


Assuntos
Músculos/metabolismo , Purinas/metabolismo , Animais , Azasserina/farmacologia , Radioisótopos de Carbono , Formiatos/metabolismo , Glicina/metabolismo , Masculino , Músculos/efeitos dos fármacos , Ratos , Ribonucleotídeos/biossíntese
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