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1.
Trials ; 22(1): 186, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33673867

RESUMEN

BACKGROUND: Depression and anxiety impact up to 1 in 5 pregnant and postpartum women worldwide. Yet, as few as 20% of these women are treated with frontline interventions such as evidence-based psychological treatments. Major barriers to uptake are the limited number of specialized mental health treatment providers in most settings, and problems with accessing in-person care, such as childcare or transportation. Task sharing of treatment to non-specialist providers with delivery on telemedicine platforms could address such barriers. However, the equivalence of these strategies to specialist and in-person models remains unproven. METHODS: This study protocol outlines the Scaling Up Maternal Mental healthcare by Increasing access to Treatment (SUMMIT) randomized trial. SUMMIT is a pragmatic, non-inferiority test of the comparable effectiveness of two types of providers (specialist vs. non-specialist) and delivery modes (telemedicine vs. in-person) of a brief, behavioral activation (BA) treatment for perinatal depressive and anxiety symptoms. Specialists (psychologists, psychiatrists, and social workers with ≥ 5 years of therapy experience) and non-specialists (nurses and midwives with no formal training in mental health care) were trained in the BA protocol, with the latter supervised by a BA expert during treatment delivery. Consenting pregnant and postpartum women with Edinburgh Postnatal Depression Scale (EPDS) score of ≥ 10 (N = 1368) will be randomized to one of four arms (telemedicine specialist, telemedicine non-specialist, in-person specialist, in-person non-specialist), stratified by pregnancy status (antenatal/postnatal) and study site. The primary outcome is participant-reported depressive symptoms (EPDS) at 3 months post-randomization. Secondary outcomes are maternal symptoms of anxiety and trauma symptoms, perceived social support, activation levels and quality of life at 3-, 6-, and 12-month post-randomization, and depressive symptoms at 6- and 12-month post-randomization. Primary analyses are per-protocol and intent-to-treat. The study has successfully continued despite the COVID-19 pandemic, with needed adaptations, including temporary suspension of the in-person arms and ongoing randomization to telemedicine arms. DISCUSSION: The SUMMIT trial is expected to generate evidence on the non-inferiority of BA delivered by a non-specialist provider compared to specialist and telemedicine compared to in-person. If confirmed, results could pave the way to a dramatic increase in access to treatment for perinatal depression and anxiety. TRIAL REGISTRATION: ClinicalTrials.gov NCT04153864 . Registered on November 6, 2019.


Asunto(s)
Ansiedad/terapia , Depresión Posparto/terapia , Depresión/terapia , Accesibilidad a los Servicios de Salud , Complicaciones del Embarazo/terapia , Psicoterapia/métodos , Telemedicina/métodos , COVID-19 , Atención a la Salud/métodos , Estudios de Equivalencia como Asunto , Femenino , Humanos , Servicios de Salud Materna , Servicios de Salud Mental/organización & administración , Partería , Enfermeras y Enfermeros , Ensayos Clínicos Pragmáticos como Asunto , Embarazo , Escalas de Valoración Psiquiátrica , Psiquiatría , Psicología , SARS-CoV-2 , Trabajadores Sociales , Especialización
2.
Int J Eat Disord ; 49(3): 260-75, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26711005

RESUMEN

OBJECTIVE: This article summarizes the literature on obstetric and gynecologic complications associated with eating disorders. METHOD: We performed a comprehensive search of the current literature on obstetric and gynecologic complications associated with eating disorders using PubMed. More recent randomized-controlled trials and larger data sets received priority. We also chose those that we felt would be the most relevant to providers. RESULTS: Common obstetric and gynecologic complications for women with eating disorders include infertility, unplanned pregnancy, miscarriage, poor nutrition during pregnancy, having a baby with small head circumference, postpartum depression and anxiety, sexual dysfunction and complications in the treatment for gynecologic cancers. There are also unique associations by eating disorder diagnosis, such as earlier cessation of breastfeeding in anorexia nervosa; increased polycystic ovarian syndrome in bulimia nervosa; and complications of obesity as a result of binge eating disorder. DISCUSSION: We focus on possible biological and psychosocial factors underpinning risk for poor obstetric and gynecological outcomes in eating disorders. Understanding these factors may improve both our understanding of the reproductive needs of women with eating disorders and their medical outcomes. We also highlight the importance of building multidisciplinary teams to provide comprehensive care to women with eating disorders during the reproductive years.


Asunto(s)
Anorexia Nerviosa/complicaciones , Bulimia Nerviosa/complicaciones , Complicaciones del Embarazo/diagnóstico , Femenino , Humanos , Embarazo
3.
Eur J Neurosci ; 18(12): 3361-6, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14686909

RESUMEN

Sensorimotor gating, measured by prepulse inhibition of the startle response (PPI), is a cross-species form of information processing that is deficient in patients with schizophrenia and is widely used as a model to study the neurobiology of this disorder. The eight known metabotropic glutamate receptors (mGluRs) are divided into three groups on the basis of sequence homology and pharmacological properties. Group I consists of mGluR5 and mGluR1, both of which are coupled positively to phospholipase C. Mice lacking mGluR5 exhibit a deficit in PPI. Like mGluR5, mGluR1 is located in regions that are involved in the modulation of PPI. To test the hypothesis that mGluR1 is involved in the modulation of PPI we assessed PPI in mGluR1 knockout (KO) mice. Littermate mGluR1 wild-type and KO mice were tested at multiple ages in a standard PPI paradigm containing a 65 dB background, 120 dB pulses and prepulses of 69, 73 and 77 dB. At all ages tested, mGluR1 KO mice exhibited a significant PPI deficit. The PPI deficit of the mGluR1 KO mice was not further exaggerated by administration of the N-methyl-d-aspartate antagonist phencyclidine nor was it reversed by administration of the dopamine antagonist raclopride (3.0 mg/kg). The PPI deficit of the mGluR1 KO mice was, however, ameliorated by administration of the mood stabilizer lamotrigine (27 mg/kg base equivalent weight), though increases in PPI were also seen with lamotrigine in the wild-type mice. Thus, both group I metabotropic glutamate receptors are involved in the regulation of PPI in mice.


Asunto(s)
Encéfalo/metabolismo , Inhibición Neural/genética , Receptores de Glutamato Metabotrópico/deficiencia , Reflejo de Sobresalto/genética , Estimulación Acústica , Animales , Antimaníacos/farmacología , Encéfalo/fisiopatología , Modelos Animales de Enfermedad , Antagonistas de Dopamina/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Femenino , Ácido Glutámico/metabolismo , Lamotrigina , Masculino , Ratones , Ratones Noqueados , Receptores de Glutamato Metabotrópico/genética , Esquizofrenia/genética , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología , Transmisión Sináptica/genética , Triazinas/farmacología
4.
CNS Spectr ; 6(10): 835-40, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15334038

RESUMEN

Depression and anxiety are among the top 10 health problems for which complementary and alternative therapies (CATs) are most frequently used, and medicinal herbs are among the most popular of these treatments. St. John's wort (Hypericum perforatum) is a perennial herb that has become a widely used depression therapy. Extracts of hypericum have shown affinity for receptors within multiple neurochemical systems. The primary active substance responsible for the antidepressant effect is not well defined, but most work has concentrated specifically on the hypericin and hyperforin components. Although hypericum has demonstrated significant antidepressant and antianxiety effects in multiple studies, there are several recent studies that do not support the previous evidence. In all reported studies, hypericum extracts have been well tolerated. In addition, new psychiatric uses for hypericum in obsessive-compulsive disorder, generalized anxiety disorder, menopausal symptoms, and alcohol dependence have been reported. Because patients are choosing to pursue CAT as a first-line therapy, psychiatrists will need to have a better understanding of phytomedicines used for treating depression and anxiety, and thus be better prepared to serve as effective allies of their patients.

5.
Am J Respir Crit Care Med ; 151(3 Pt 2): S75-87, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7533609

RESUMEN

Cystic fibrosis (CF) is caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The major manifestations are on the airway epithelial surface, with purulent mucus, recurrent infections, chronic inflammation, and loss of lung function. Consequent to mutations in both parental genes, airway epithelial cells have insufficient CFTR function. Because this can be corrected in vitro by transfer of the normal CFTR gene into airway epithelial cells, it is reasonable to hypothesize that the respiratory manifestations of CF could be prevented by transfer of the normal human CFTR cDNA to the airway epithelium in vivo. Over the past 6 years, our laboratory has developed a strategy to accomplish this goal using a replication deficient E1-E3- recombinant adenovirus (Ad) serotype 5 vector containing the normal human CFTR cDNA (AdCFTR). Studies with experimental animals demonstrate that with administration of such a vector to the airways, the human CFTR cDNA could be transferred to the airway epithelium, with expression of the human CFTR cDNA for at least 6 weeks. Extensive preclinical studies in vitro and in vivo demonstrated that the risks to humans were sufficiently low to initiate a Phase I trial using the AdCFTR vector to treat the respiratory manifestations of CF in humans. Following approval by the National Heart, Lung, and Blood Institute Institutional Review Board, the National Institutes of Health Biosafety Committee, the National Institutes of Health Recombinant DNA Advisory Committee, and the Food and Drug Administration, we initiated the first human trial of gene therapy for CF on April 17, 1993. The clinical study is still ongoing, with safety and efficacy data being evaluated, but there is clear evidence that it is feasible to transfer and express the normal CFTR cDNA to the airway epithelium in vivo in individuals with CF.


Asunto(s)
Fibrosis Quística/terapia , Terapia Genética , Pulmón/fisiopatología , Adenoviridae/genética , Animales , Canales de Cloruro/genética , Canales de Cloruro/fisiología , Ensayos Clínicos como Asunto , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística , ADN Complementario/genética , Epitelio/metabolismo , Regulación de la Expresión Génica , Vectores Genéticos , Humanos , Pulmón/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología
6.
Int J Neurosci ; 78(1-2): 21-32, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7829288

RESUMEN

Classical conditioning is involved in the acquisition of chronic pain. The present study investigated whether experimental pain responses can be conditioned using auditory stimuli in a differential trace conditioning paradigm. 16 healthy subjects served as paid volunteers. The UCS was an intracutaneous electrical stimulus applied to the left middle-finger (10 ms duration). Tones of 1000 and 1400 Hz (both 80 dB SPL, 50 ms) were used as CS+ and CS-, respectively. A trace conditioning paradigm was used with an 800 ms interval between CS and UCS. Somatosensory event related potentials (SEP) and auditory event related potentials (AEP) were recorded from 29 electrode sites. Subjective pain reports were measured with an adjective list that allowed a detailed description of subjects' sensations elicited by painful and auditory stimuli. Data revealed significant differences of the subjective sensations between the CS+ and CS-, but no differences in the amplitudes and latencies of the P50, N100, P200, and P300 AEP components. No changes in the topographical organization of the CS+ and CS- were found. A significant differential negativity in the brain sites responsible for processing the UCS was obtained, which is attributed to the anticipation of the UCS after CS+ presentation.


Asunto(s)
Condicionamiento Clásico/fisiología , Dolor/fisiopatología , Estimulación Acústica , Adulto , Encéfalo/fisiología , Enfermedad Crónica , Aprendizaje Discriminativo , Estimulación Eléctrica , Electroencefalografía , Potenciales Evocados Somatosensoriales , Humanos , Dolor/diagnóstico , Dimensión del Dolor , Encuestas y Cuestionarios
7.
Biofeedback Self Regul ; 19(1): 1-11, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8167160

RESUMEN

The negativity of slow cortical potentials (SCP) of the surface EEG is a measure of brain excitability, correlating with motor and cognitive preparation. Self-control of SCP positivity has been shown to reduce seizure activity. Following SCP biofeedback from a central EEG electrode position, subjects gained bidirectional control over their SCP. The current study used a modified feedback methodology, and found a positive relationship between negativity and magnitude of EMG startle response (a measure of cortical and subcortical arousal, particularly aversive response disposition). Greater success in SCP differentiation was associated with self-report of less relaxation during negativity training.


Asunto(s)
Biorretroalimentación Psicológica/fisiología , Potenciales Evocados Visuales/fisiología , Reflejo de Sobresalto/fisiología , Adulto , Biorretroalimentación Psicológica/métodos , Electroencefalografía , Electromiografía , Femenino , Humanos , Masculino
8.
Psychophysiology ; 31(1): 107-10, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8146248

RESUMEN

Recent human and animal research suggests that the startle reflex might serve as a psychophysiological indicator of the emotional valence of foreground stimulation. The present experiment was designed to evaluate the emotional effects of positive and negative odorant stimuli. We examined the effects of continuous hydrogen sulphide (H2S) and vanillin stimulation on the magnitude of the acoustic startle reflex (measured at the M. orbicularis oculi) and on ratings of subjective valence in 16 healthy subjects. In accordance with the view that odors have emotional qualities, we found that H2S, a presumed negative foreground stimulus, significantly enhanced the startle-reflex amplitude relative to neutral air stimulation, whereas vanillin, a positive foreground stimulus, tended to reduce the reflex amplitude compared with neutral air stimulation. Both odorant stimuli were rated as equally intense by the subjects, and heart rate and electrodermal activity were not affected differentially by the two odorants.


Asunto(s)
Emociones/fisiología , Odorantes , Reflejo de Sobresalto/fisiología , Estimulación Acústica , Adulto , Benzaldehídos/farmacología , Electrocardiografía/efectos de los fármacos , Electromiografía/efectos de los fármacos , Electrooculografía/efectos de los fármacos , Emociones/efectos de los fármacos , Femenino , Aromatizantes/farmacología , Respuesta Galvánica de la Piel/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Humanos , Sulfuro de Hidrógeno/farmacología , Masculino , Reflejo de Sobresalto/efectos de los fármacos
9.
Eur J Biochem ; 212(3): 727-35, 1993 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8385010

RESUMEN

Cardiolipin, a unique dimeric phospholipid of bacteria and mitochondria, can be synthesized by two alternative pathways discovered in rat and Escherichia coli, respectively. In mitochondrial preparations from fungi (Saccharomyces cerevisiae, Neurospora crassa), higher plants (Phaseolus aureus), molluscs (Mytilus edulis) and mammals (rat liver, bovine adrenal gland), cardiolipin was synthesized from CDP-diacylglycerol and phosphatidylglycerol, suggesting a common eukaryotic mechanism of cardiolipin formation which is in contrast to the prokaryotic biosynthesis from two molecules of phosphatidylglycerol. All mitochondrial cardiolipin synthases were inhibited by lysophosphatidylglycerol, were insensitive to N-ethylmaleimide and required divalent cations, although they had different cation specificities. The molecular species of cardiolipin from rat liver, bovine heart, S. cerevisiae and N. crassa were analysed by high-performance liquid chromatography of the derivative 1,3-bis[3'-sn-phosphatidyl]-2-benzoyl-sn-glycerol dimethyl ester. Cardiolipins from these organisms contained mainly monounsaturated or diunsaturated chains with 16 or 18 carbon atoms, resulting in a relatively homogeneous distribution of double bonds and carbon numbers among the four acyl positions. About half of the molecular species were symmetrical, i.e. they combined two identical diacylglycerol moieties. In N. crassa, the same species pattern was found at growth temperatures of 25 degrees C and 37 degrees C. Tentative molecular models were created for the most abundant molecular species and subjected to energy minimization. Geometric data, derived from these models, suggested similarities in the gross structure of the major cardiolipin species from different sources.


Asunto(s)
Cardiolipinas/biosíntesis , Fabaceae/metabolismo , Proteínas de la Membrana , Mitocondrias/metabolismo , Neurospora crassa/metabolismo , Fosfotransferasas/metabolismo , Plantas Medicinales , Saccharomyces cerevisiae/metabolismo , Transferasas (Grupos de Otros Fosfatos Sustitutos) , Glándulas Suprarrenales/metabolismo , Animales , Bivalvos , Cardiolipinas/química , Cardiolipinas/aislamiento & purificación , Cationes Bivalentes , Bovinos , Células Eucariotas/metabolismo , Branquias/metabolismo , Cinética , Mitocondrias Hepáticas/metabolismo , Modelos Moleculares , Conformación Molecular , Ratas , Ratas Sprague-Dawley
10.
Psychopharmacology (Berl) ; 110(3): 337-41, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-7831428

RESUMEN

Activation of arterial blood pressure has been shown to influence higher central nervous activity. In animals, induction of sleep-like states and increases of seizure and pain thresholds in response to baroreceptor stimulation have been reported. In certain human groups, mechanical stimulation of the carotid baroreceptors also increases pain thresholds. The present paper examines the hypothesis that smokers show baroreceptor dependent antinociception as compared to non-smokers. It is speculated that one effect which rewards smoking is the nicotine induced phasic blood pressure increase which leads to baroreceptor stimulation and dampens pain perception. One hundred and twenty subjects were investigated using a recently developed mechanical baroreceptor stimulation technique and an electrical pain stimulus. The group of heavy smokers showed the predicted effect: their pain thresholds were enhanced during conditions of increased baroreceptor activity as compared to the control condition. The group of medium, light and non-smokers, however, did not show this effect. Neither blood lipid levels nor diastolic or systolic blood pressure paralleled the group differences on baroreceptor dependent antinociception. In heavy smokers, the nicotine induced phasic blood pressure increases might have baroreceptor dependent pain dampening effects, which might be among the reinforcing qualities of smoking.


Asunto(s)
Lípidos/sangre , Nociceptores/fisiología , Presorreceptores/fisiología , Fumar/sangre , Fumar/fisiopatología , Adulto , Presión Sanguínea/efectos de los fármacos , Colesterol/sangre , Café , Estimulación Eléctrica , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Dolor/psicología , Psicometría
11.
Biochim Biophys Acta ; 898(1): 23-36, 1987 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-2950925

RESUMEN

The cel mutant of Neurospora, partially blocked in fatty acid synthesis and lacking temperature compensation of its circadian rhythm below 22 degrees C, had a phospholipid fatty acid composition in liquid shaker culture distinctly different from that of a cel+ control strain. During growth, cel+ exhibited a reproducible increase in its linoleic acid level from about 32 to a plateau at 63 mol%, and a corresponding decrease in its linolenic acid level from about 40 to a plateau at 10 mol%. The level of palmitic acid was constant at 19 mol%. In the cel strain, the linoleic acid level was constant at 54 mol% while the palmitic acid level increased from about 12 to about 23 mol%. Supplementation with palmitic or linoleic acids altered the patterns of fatty acid composition of cel, but did not affect the pattern of cel+. Altered fatty acid composition cosegregated with the cel marker. The mitochondrial phospholipids of cel in liquid culture also had abnormal fatty acid composition, as did the whole mycelial phospholipids on solid medium. These results are consistent with the involvement of membrane homeostasis in the temperature compensation of circadian rhythms.


Asunto(s)
Ritmo Circadiano , Lípidos de la Membrana/análisis , Mutación , Neurospora crassa/crecimiento & desarrollo , Neurospora/crecimiento & desarrollo , Fosfolípidos/análisis , Membrana Celular/análisis , Ácidos Grasos/análisis , Neurospora crassa/genética , Temperatura
12.
Proc Natl Acad Sci U S A ; 79(3): 825-9, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6461008

RESUMEN

The circadian rhythm of conidiation (spore formation) in Neurospora crassa is known to be temperature compensated, that is, the period is only slightly affected by the incubation temperature. Thus, the Q10 (the relative rate enhancement corresponding to a 10 degrees C rise in temperature) of the rhythm of the bd csp strain from 14 to 30 degrees C was 1.1, whereas the Q10 of the uncompensated growth rate in the same interval was 2.4. A mutation at the cel locus resulted in loss of the temperature-compensation property in cultures grown below 22 degrees C. The Q10 of the rhythm below 22 degrees C was 2.2, and periods of about 40 hr were observed. In contrast, the Q10 of the rhythm above 22 degrees C was 1.1, with circadian periods of 18-21 hr. Thus, cel displayed a threshold temperature or "break point" for the temperature compensation of its rhythm. Supplementation of cel strains, which require fatty acids, with unsaturated or short-chain fatty acids raised the threshold temperature to 26 degrees C, whereas supplementation with long-chain saturated fatty acids lowered it to 18 degrees C. These data suggest a role for fatty acids, as liquid components or as cellular metabolites, in the mechanism of temperature compensation.


Asunto(s)
Ritmo Circadiano , Neurospora crassa/fisiología , Neurospora/fisiología , Ácidos Grasos/fisiología , Mutación , Neurospora crassa/genética , Esporas Fúngicas , Temperatura
13.
J Bacteriol ; 139(3): 977-83, 1979 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-158008

RESUMEN

To assess their effects on the conidiation rhythm in Neurospora, 14 saturated fatty acids from 6 to 24 carbons long were used to supplement the bd csp and bd csp cel strains. Both strains express a circadian spore-forming rhythm when grown on solid media; the cel mutation confers a partial fatty acid requirement. Fatty acid supplements from 8 to 13 carbons long lengthened the free-running period of bd csp cel compared with the control value of 21 h; the maximal effect (33 h) was obtained with nonanoic acid (9:0) at a concentration of 5 x 10(-4) M. In contrast, the period of bd csp remained unchanged under all experimental conditions. The short-chain fatty acids (<14 carbons) reduced the rate of advance of the growth front in both strains, compared with unsupplemented controls. However, this inhibition did not appear to be responsible for the lengthened periods in bd csp cel. Nor was direct incorporation of the short-chain (period-lengthening) fatty acids into mycelial total lipids responsible, since such incorporation was not observed. In fact, extensive metabolic conversion of these supplements by both strains was indicated by the disappearance of short-chain fatty acids from the agar media coupled with their absence in mycelial lipids, and by the liberation of (14)CO(2) from cultures supplemented with [1-(14)C]lauric acid (12:0).


Asunto(s)
Ritmo Circadiano/efectos de los fármacos , Ácidos Grasos/farmacología , Neurospora crassa/crecimiento & desarrollo , Neurospora/crecimiento & desarrollo , Neurospora crassa/efectos de los fármacos , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/fisiología , Relación Estructura-Actividad
14.
J Bacteriol ; 137(2): 912-5, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-154511

RESUMEN

Employing a fatty acid-requiring strain (bd csp cel) of Neurospora crassa, the 21.5-h period of the circadian spore-forming rhythm was manipulated by fatty acid supplementation. The addition to the medium of an unsaturated fatty acid (oleic, linoleic, or linolenic acid) lengthened the period to 26, 40, or 33 h, respectively. Ther period-lengthening effect of linoleic acid was proportional to its concentration up to 1.3 X 10(-4) M, and also was reversed by the addition to the medium of a saturated fatty acid, palmitic acid. None of these period-lengthening effects was observed in the prototrophic strain (bd csp cel+).


Asunto(s)
Ritmo Circadiano , Ácidos Grasos Insaturados/metabolismo , Neurospora crassa/fisiología , Neurospora/fisiología , Medios de Cultivo , Ácidos Linoleicos/metabolismo , Ácidos Linolénicos/metabolismo , Mutación , Ácidos Oléicos/metabolismo , Ácidos Palmíticos/metabolismo , Esporas Fúngicas
16.
J Biol Chem ; 250(18): 7173-81, 1975 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-126231

RESUMEN

The glycerophospholipids of cultures of Neurospora crassa were extracted, deacylated, and analyzed. In addition to a wild-type strain, several auxotrophic mutant strains were examined: chol-1 (defective S-adenosylmethionine: phosphatidylethanolamine methyltransferase), chol-2 (defective S-adenosyl methionine:phosphatidylmonomethylethanolamine (dimethylethanolamine) methyltransferase), and inos (defective myoinositol-1-phosphate phosphatase). In addition, a double mutant strain, chol-1;chol-2, was constructed. Cultures of the mutant strains grown with concentrations of supplement(s) just adequate to support growth had bizarre phospholipid compositions. By appropriate choice of mutant and supplement(s), it was possible to vary the relative level of every phospholipid of the organism, with the exception of cardiolipin. The maximum ranges encountered for the zwitterionic species, expressed as per cent of total phospholipid phosphorus, were lecithin (0.9 to 53.1%), phosphatidyldimethylethanolamine (0.0 to 55.5%), phosphatidylmonomethylethanolamine (0.0 to 53.9%), and phosphatidylethanolamine (9.8 to 43.3%). For the anionic species, the ranges were phosphatidylserine (1.7 to 10.4%) and phosphatidylinositol (3.6 to 25.1%). Despite the wide variation of the relative proportions of the individual phospholipid species, five quantities remained constant: the cardiolipin content, the total phospholipid content, the total content of the zwitterionic species, the total content of the anionic species, and the ratio of the zwitterionic to anionic totals. The data suggest the existence of an internal compensation mechanism, the net effect of which is maintenance of a fairly constant contribution by the phospholipid components to the over-all membrane charge.


Asunto(s)
Colina/metabolismo , Inositol/metabolismo , Neurospora crassa/metabolismo , Neurospora/metabolismo , Fosfolípidos/metabolismo , Glicerilfosforilcolina/metabolismo , Mutación , Especificidad de la Especie
17.
J Bacteriol ; 108(3): 1310-7, 1971 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4400392

RESUMEN

A morphological mutant (col-2) of Neurospora, which is partially deficient in glucose-6-phosphate dehydrogenase (G-6-PD) activity and has lower levels of reduced nicotinamide adenine dinucleotide phosphate (NADPH), accumulated three-fold more triglycerides during log-phase growth than the wild-type strain. Increased lipid deposition was not found in other strains that included slow-growing morphological mutants, NADPH-deficient strains, G-6-PD-deficient mutants, wild-type revertants from col-2, and a cel, col-2 double mutant. The cel, col-2 strain was supplemented with an exogenous source of fatty acids because it cannot synthesize these lipid moieties. The observed normal lipid content of this strain suggests that the lipid deposition in col-2 on glucose is due to an overstimulation of fatty acid synthesis and not a deficiency in fatty acid breakdown. The neutral lipid levels in both wild type and col-2 were decreased to identical levels when grown on glutamate as a carbon source. This effect was not due to changes in glutamic dehydrogenase levels. The omission of citrate from the glutamate medium reduced wild-type neutral lipid levels even further, but had no effect on col-2. The variations with time in the neutral lipid levels of col-2 upon changes in these carbon sources are presented, as well as a discussion of the possible types of regulatory effects unique to the col-2 mutation which might affect fatty acid synthesis.


Asunto(s)
Medios de Cultivo , Lípidos/biosíntesis , Mutación , Neurospora/metabolismo , Cromatografía de Gases , Citratos/metabolismo , Ácidos Grasos/análisis , Ácidos Grasos/biosíntesis , Genética Microbiana , Glucosa/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Glutamato Deshidrogenasa/metabolismo , Glutamatos/metabolismo , Lípidos/análisis , NADP/metabolismo , Neurospora crassa/análisis , Neurospora crassa/enzimología , Neurospora crassa/crecimiento & desarrollo , Neurospora crassa/metabolismo , Nitratos/metabolismo , Fosfolípidos/análisis , Fosfolípidos/biosíntesis , Compuestos de Amonio Cuaternario/metabolismo , Triglicéridos/biosíntesis , Urea/metabolismo , Xilosa/metabolismo
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