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1.
J Antimicrob Chemother ; 79(4): 868-874, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38394460

RESUMEN

OBJECTIVES: Recently, reports on antimicrobial-resistant Bacteroides and Prevotella isolates have increased in the Netherlands. This urged the need for a surveillance study on the antimicrobial susceptibility profile of Bacteroides, Phocaeicola, Parabacteroides and Prevotella isolates consecutively isolated from human clinical specimens at eight different Dutch laboratories. METHODS: Each laboratory collected 20-25 Bacteroides (including Phocaeicola and Parabacteroides) and 10-15 Prevotella isolates for 3 months. At the national reference laboratory, the MICs of amoxicillin, amoxicillin/clavulanic acid, piperacillin/tazobactam, meropenem, imipenem, metronidazole, clindamycin, tetracycline and moxifloxacin were determined using agar dilution. Isolates with a high MIC of metronidazole or a carbapenem, or harbouring cfiA, were subjected to WGS. RESULTS: Bacteroides thetaiotaomicron/faecis isolates had the highest MIC90 values, whereas Bacteroides fragilis had the lowest MIC90 values for amoxicillin/clavulanic acid, piperacillin/tazobactam, meropenem, imipenem and moxifloxacin. The antimicrobial profiles of the different Prevotella species were similar, except for amoxicillin, for which the MIC50 ranged from 0.125 to 16 mg/L for Prevotella bivia and Prevotella buccae, respectively. Three isolates with high metronidazole MICs were sequenced, of which one Bacteroides thetaiotaomicron isolate harboured a plasmid-located nimE gene and a Prevotella melaninogenica isolate harboured a nimA gene chromosomally.Five Bacteroides isolates harboured a cfiA gene and three had an IS element upstream, resulting in high MICs of carbapenems. The other two isolates harboured no IS element upstream of the cfiA gene and had low MICs of carbapenems. CONCLUSIONS: Variations in resistance between species were observed. To combat emerging resistance in anaerobes, monitoring resistance and conducting surveillance are essential.


Asunto(s)
Antiinfecciosos , Metronidazol , Humanos , Meropenem , Moxifloxacino , Países Bajos , Laboratorios , Bacteroides , Antibacterianos/farmacología , Carbapenémicos , Bacteroides fragilis , Imipenem , Pruebas de Sensibilidad Microbiana , Piperacilina , Tazobactam , Prevotella/genética , Amoxicilina , Ácido Clavulánico
2.
Tijdschr Psychiatr ; 66(3): 151-155, 2024.
Artículo en Holandés | MEDLINE | ID: mdl-38650512

RESUMEN

BACKGROUND: Residents in psychiatry can be confronted with patient-related stressful experiences which can be impactful. Guidelines for dealing with these are lacking. AIM: Questioning residents in psychiatry about patient-related stressful adversities, their impact and resources to contribute to the existing literature. METHOD: Qualitative study through semi-structured interviews of six psychiatry residents, followed by data-analysis using thematic analysis. RESULTS: Reported patient-related stressful experiences were suicide, verbal and imminent physical aggression, questioning expertise, concerns about legal consequences, powerlessness and expectations. Cognitive and physical impact was experienced with symptoms similar to acute stress disorder. The most important resource is social support. CONCLUSION: In this study new patient related stressful experiences are reported that have not previously been described in the literature. Since estimating the impact of a patient related stressful experience proves difficult, it seems appropriate that the environment of the resident offers active support and further development of residents’ skills is stimulated.


Asunto(s)
Internado y Residencia , Psiquiatría , Estrés Psicológico , Humanos , Psiquiatría/educación , Estrés Psicológico/psicología , Apoyo Social , Masculino , Adulto , Femenino , Investigación Cualitativa , Agresión/psicología , Suicidio/psicología
3.
Int J Cosmet Sci ; 37(6): 627-35, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25945793

RESUMEN

OBJECTIVE: A new protocol is described for assessing the efficacy of the dispenser of some packaging systems (PSs) of preservative-free cosmetic products in protecting both their contained formula and their delivered doses. METHODS: Practically, aiming at mimicking contacts with a non-sterile skin or fingers, the dispensing system is put into contact with a pre-contaminated fabric by a standardized colonization of P. aeruginosa. RESULTS: When applied to three different types of packaging, results show clear differences in both criteria between these conditioning articles, that is variable efficacies in protecting the contained product and the delivered doses, knowing that the first aspect is of paramount importance. CONCLUSION: The proposed protocol is proved being able to discriminate between different PSs and provides information on strong and weak features of certain types dispensing technologies prone to efficiently decrease either the dose contamination or to prevent contamination in reaching the contained product. Therefore, the proposed protocol can contribute to an objective selection of a PS for protecting a cosmetic care product with a low content of preservative or preservative free.


Asunto(s)
Cosméticos , Embalaje de Productos , Bacterias , Humanos , Conservadores Farmacéuticos , Agua
4.
JAC Antimicrob Resist ; 4(2): dlac041, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35445193

RESUMEN

Objectives: Plasmid-mediated colistin resistance can be transferred from animals to humans. We investigated the prevalence of carriage of mcr-mediated colistin-resistant Escherichia coli and Klebsiella pneumoniae (ColR-E/K) in veterinary healthcare workers and in the general population in the Netherlands. Methods: Two cross-sectional population studies were performed: one among veterinary healthcare workers and one in the general population. Participants sent in a faecal sample and filled in a questionnaire. Samples were analysed using selective enrichment and culture. Mobile colistin resistance genes (mcr) were detected by PCR and ColR-E/K were sequenced using Illumina and Nanopore technologies. Results: The prevalence of mcr-mediated ColR-E/K was 0.2% (1/482, 95% CI 0.04%-1.17%) among veterinary personnel and 0.8% (5/660, 95% CI 0.3%-1.8%) in the population sample. mcr-1 was found in E. coli from four persons, mcr-8 in K. pneumoniae from one person and another person carried both mcr-1 and mcr-8 in a K. pneumoniae isolate. mcr-1 was found on different plasmid types (IncX4, IncI1 and IncI2), while mcr-8 was found on IncF plasmids only. Conclusions: mcr-mediated ColR-E/K resistance was uncommon in both populations. Professional contact with animals does not increase the chance of carriage of these bacteria in the Netherlands at present. mcr-8 was found for the first time in the Netherlands. Surveillance of colistin resistance and its underlying mechanisms in humans, livestock and food is important in order to identify emerging trends in time.

5.
J Med Genet ; 47(8): 507-12, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19542079

RESUMEN

BACKGROUND: Leigh syndrome is an early onset, progressive, neurodegenerative disorder with developmental and motor skills regression. Characteristic magnetic resonance imaging abnormalities consist of focal bilateral lesions in the basal ganglia and/or the brainstem. The main cause is a deficiency in oxidative phosphorylation due to mutations in an mtDNA or nuclear oxidative phosphorylation gene. METHODS AND RESULTS: A consanguineous Moroccan family with Leigh syndrome comprise 11 children, three of which are affected. Marker analysis revealed a homozygous region of 11.5 Mb on chromosome 20, containing 111 genes. Eight possible mitochondrial candidate genes were sequenced. Patients were homozygous for an unclassified variant (p.P193L) in the cardiolipin synthase gene (CRLS1). As this variant was present in 20% of a Moroccan control population and enzyme activity was only reduced to 50%, this could not explain the rare clinical phenotype in our family. Patients were also homozygous for an amino acid substitution (p.L159F) in C20orf7, a new complex I assembly factor. Parents were heterozygous and unaffected sibs heterozygous or homozygous wild type. The mutation affects the predicted S-adenosylmethionine (SAM) dependent methyltransferase domain of C20orf7, possibly involved in methylation of NDUFB3 during the assembly process. Blue native gel electrophoresis showed an altered complex I assembly with only 30-40% of mature complex I present in patients and 70-90% in carriers. CONCLUSIONS: A new cause of Leigh syndrome can be a defect in early complex I assembly due to C20orf7 mutations.


Asunto(s)
Complejo I de Transporte de Electrón/metabolismo , Enfermedad de Leigh/enzimología , Enfermedad de Leigh/genética , Metiltransferasas/genética , Proteínas Mitocondriales/genética , Mutación/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Sustitución de Aminoácidos/genética , Secuencia de Bases , Preescolar , Análisis Mutacional de ADN , Complejo I de Transporte de Electrón/genética , Familia , Femenino , Homocigoto , Humanos , Enfermedad de Leigh/diagnóstico por imagen , Enfermedad de Leigh/metabolismo , Leucocitos Mononucleares/enzimología , Imagen por Resonancia Magnética , Masculino , Metiltransferasas/química , Proteínas Mitocondriales/química , Datos de Secuencia Molecular , Marruecos , Linaje , Tomografía Computarizada por Rayos X , Adulto Joven
6.
J Med Genet ; 46(11): 776-85, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19578034

RESUMEN

BACKGROUND: Mutations in the DNA polymerase-gamma (POLG) gene are a major cause of clinically heterogeneous mitochondrial diseases, associated with mtDNA depletion and multiple deletions. OBJECTIVE: To determine the spectrum of POLG mutations in our Dutch patient cohort, to evaluate the pathogenicity of novel mutations, and to establish genotype-phenotype correlations. RESULTS: The authors identified 64 predominantly recessive mutations in 37 patients from a total of 232 patients, consisting of 23 different mutations. The substitution p.A467T was most frequently observed (n = 23), but was as frequent in childhood cases as in adult cases. Five new pathogenic recessive mutations, p.Lys925ArgfsX42, p.R275X, p.G426S, p.A804T and p.R869Q were identified. The known dominant chronic progressive external ophthalmoplegia (CPEO) mutation p.R943H was for the first time associated with premature ovarian failure as well. In 19 patients the authors identified only a single recessive mutation, or a sequence variant with unclear clinical significance. The data substantiate earlier observations that in POLG patients a fatal status epilepticus and liver failure can be triggered by sodium valproate. It is therefore important to exclude POLG mutations before administering this treatment. CONCLUSION: The clinical features of the patient are the most important features to select putative POLG mutation carriers and not the presence of mtDNA deletions or OXPHOS (oxidative phosphorylation) activity. The authors conclude that POLG mutations are an important cause of heterogeneous mitochondrial pathology and that more accurate genotype-phenotype correlations allow a more rapid genetic diagnosis and improved prognosis for mutation carriers.


Asunto(s)
ADN Polimerasa Dirigida por ADN/genética , Mutación , Adolescente , Adulto , Anciano , Secuencia de Aminoácidos , Niño , Preescolar , Estudios de Cohortes , Simulación por Computador , Análisis Mutacional de ADN , ADN Polimerasa gamma , ADN Mitocondrial/genética , Femenino , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Oftalmoplejía Externa Progresiva Crónica/genética , Linaje , Fenotipo , Insuficiencia Ovárica Primaria/genética , Alineación de Secuencia
7.
Science ; 151(3715): 1225-6, 1966 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-4956158

RESUMEN

Vesiclulation and other anomalies were observed in the zona pellucida about the ovum of female baboons (Papio anubis) that had received treatment with Pergonal and human chorionic gonadotropin; and in somiie instances the zona pellucida was absent.


Asunto(s)
Gonadotropina Coriónica/farmacología , Gonadotropinas Hipofisarias/farmacología , Óvulo/efectos de los fármacos , Animales , Femenino , Haplorrinos , Técnicas In Vitro
8.
J Med Genet ; 44(4): e74, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17400793

RESUMEN

BACKGROUND: Detection of mutations in the mitochondrial DNA (mtDNA) is usually limited to common mutations and the transfer RNA genes. However, mutations in other mtDNA regions can be an important cause of oxidative phosphorylation (OXPHOS) disease as well. OBJECTIVE: To investigate whether regions in the mtDNA are preferentially mutated in patients with OXPHOS disease. METHODS: Screening of the mtDNA for heteroplasmic mutations was performed by denaturing high-performance liquid chromatography analysis of 116 patients with OXPHOS disease but without the common mtDNA mutations. RESULTS: An mtDNA sequence variant was detected in 15 patients, 5 of which were present in the ND5 gene. One sequence variant was new and three were known, one of which was found twice. The novel sequence variant m.13511A-->T occurred in a patient with a Leigh-like syndrome. The known mutation m.13513G-->A, associated with mitochondrial encephalomyopathy lactic acidosis and stroke-like syndrome (MELAS) and MELAS/Leigh/Leber hereditary optic neuropathy overlap syndrome, was found in a relatively low percentage in two patients from two different families, one with a MELAS/Leigh phenotype and one with a MELAS/chronic progressive external ophthalmoplegia phenotype. The known mutation m.13042G-->A, detected previously in a patient with a MELAS/myoclonic epilepsy, ragged red fibres phenotype and in a family with a prevalent ocular phenotype, was now found in a patient with a Leigh-like phenotype. The sequence variant m.12622G-->A was reported once in a control database as a polymorphism, but is reported in this paper as heteroplasmic in three brothers, all with infantile encephalopathy (Leigh syndrome) fatal within the first 15 days of life. Therefore, a causal relationship between the presence of this sequence variant and the onset of mitochondrial disease cannot be entirely excluded at this moment. CONCLUSIONS: Mutation screening of the ND5 gene is advised for routine diagnostics of patients with OXPHOS disease, especially for those with MELAS- and Leigh-like syndrome with a complex I deficiency.


Asunto(s)
Complejo I de Transporte de Electrón/genética , Enfermedades Mitocondriales/genética , Proteínas Mitocondriales/genética , Fosforilación Oxidativa , Secuencia de Aminoácidos , Animales , Encéfalo/anomalías , Niño , Cromatografía Líquida de Alta Presión , Análisis Mutacional de ADN , ADN Mitocondrial/genética , Enfermedades en Gemelos , Complejo I de Transporte de Electrón/química , Complejo I de Transporte de Electrón/deficiencia , Complejo I de Transporte de Electrón/fisiología , Resultado Fatal , Femenino , Pruebas Genéticas , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Recién Nacido , Enfermedad de Leigh/genética , Síndrome MELAS/genética , Masculino , Mitocondrias Musculares/enzimología , Proteínas Mitocondriales/química , Proteínas Mitocondriales/deficiencia , Proteínas Mitocondriales/fisiología , Datos de Secuencia Molecular , Mutación Missense , Fenotipo , Subunidades de Proteína , Alineación de Secuencia , Homología de Secuencia de Aminoácido
9.
Histol Histopathol ; 33(12): 1335-1345, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29985521

RESUMEN

PURPOSE: Urethral reconstruction is performed in patients with urethral strictures or for correction of congenital disorders. In the case of shortage of tissue, engineered tissue may enhance urethral reconstruction. As the corpus spongiosum (CS) is important in supporting the function of the urethra, tissue engineering of the urethra should be combined with reconstruction of a CS. For that purpose, detailed knowledge of the composition of the CS, more specifically its extracellular matrix (ECM) and vascularization is needed for scaffold design. The objective of this study is to analyze the microarchitecture of the CS through (immuno) histology and scanning electron microscopy (SEM). METHODS: The CS including the urethra of patients undergoing male-to-female genital confirming surgery was harvested. This CS was fixed and processed for either (immuno) histology or for SEM. RESULTS: Four layers could be distinguished in the CS; first a transition zone from urethra epithelium to a collagen rich layer, which was highly vascularized, followed by a second, elastin rich layer. The third layer was formed by veins, arteries and vascular spaces and the last layer showed the transition from this vascular rich region to the collagen rich tunica albuginea. In this layer collagen bundles intertwined with elastic fibres. In the CS different components of the ECM were visible and distinguishable. CONCLUSION: This study provides novel and detailed information on the microarchitecture of the CS and the distribution of vascularization, which is important for scaffold design in tissue engineering.


Asunto(s)
Pene/anatomía & histología , Uretra/anatomía & histología , Humanos , Masculino
10.
JIMD Rep ; 22: 39-45, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25732997

RESUMEN

In a 28-year-old male with a mild mitochondrial myopathy manifesting as exercise intolerance and early signs of cardiomyopathy without muscle weakness or ophthalmoplegia, we identified two novel mutations in the SLC25A4 gene: c.707G>C in exon 3 (p.(R236P)) and c.116_137del in exon 2 (p.(Q39Lfs*14)). Serum lactate levels at rest were elevated (12.7 mM). Both the patient's father and brother were heterozygous carriers of the c.707G>C mutation and were asymptomatic. The second mutation causes a 22 bp deletion leading to a frame shift likely giving rise to a premature stop codon and nonsense-mediated decay (NMD). The segregation of the mutations could not be tested directly as the mother had died before. However, indirect evidence from NMD experiments showed that the two mutations were situated on two different alleles in the patient. This case is unique compared to other previously reported patients with either progressive external ophthalmoplegia (PEO) or clear hypertrophic cardiomyopathy with exercise intolerance and/or muscle weakness carrying recessive mutations leading to a complete absence of the SLC25A4 protein. Most likely in our patient, although severely reduced, SLC25A4 is still partially present and functional.

11.
Endocrinology ; 132(1): 6-12, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8419146

RESUMEN

Circulating relaxin concentrations in the human rise in the late luteal phase and increase further in response to increasing circulating CG concentrations immediately after implantation. Similar events have not been documented in the laboratory macaque because of the lack of sensitivity of heterologous assay systems. A homologous enzyme-linked immunosorbent assay for authentic macaque relaxin was developed and validated. Using this enzyme-linked immunosorbent assay, relaxin concentrations were measured in peripheral and ovarian venous blood collected from cynomolgus and rhesus macaques. Relaxin concentrations rose in the late luteal phase of nonconceptive menstrual cycles in cynomolgus macaques, but it was not detected at other times in the cycle. In conceptive cycles, relaxin concentrations rose rapidly in close association with the appearance of mCG 13-14 days after mating. Pregnant rhesus macaques also had elevated relaxin concentrations in blood samples collected on days 15-17 postbreeding. Relaxin concentrations disappeared immediately after luteectomy or ablation of the trophoblast by either surgery or administration of methotrexate. The rise of relaxin paralleled the rise of mCG until 20-25 days postbreeding, while progesterone concentrations declined during this same time period. The lack of correlation between relaxin and progesterone secretion profiles suggests that either the cellular origins or the intracellular mechanisms promoting the secretion of these hormones are different. The periimplantational profile of serum relaxin in macaques was similar to the profile of relaxin observed during early human pregnancy.


Asunto(s)
Implantación del Embrión/fisiología , Relaxina/metabolismo , Animales , Cuerpo Lúteo/fisiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Fase Luteínica/fisiología , Macaca fascicularis , Macaca mulatta , Metotrexato/farmacología , Embarazo , Progesterona/metabolismo , Relaxina/análisis , Trofoblastos/fisiología
12.
Endocrinology ; 96(1): 185-92, 1975 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1109902

RESUMEN

The concentrations of androstenedione, testosterone and cortisol have been measured in the maternal peripheral plasma of normal pregnant rhesus monkeys (Macaca mulatta), and in rhesus monkeys treated daily with dexamethasone during late pregnancy. During the last 30 days of pregnancy, the mean plasma concentrations of androstenedione, testosterone and cortisol were about 1400-2000 pg/m1375-425pg/ml and 300-400 ng/ml, respectively. None of these steroids increased significantly before parturition. As there was no rise in maternal androgens in late pregnancy when plasma estrogens increase sharply, it suggested that his elevation of plasma estrogens is related to an increase of fetal precursors Dexamethasone treatment resulted in 90% suppression of plasma cortisol and 40%-60% suppression of androstendione and testosterone. As the suppression of maternal androgens was of lesser magnitude than the decline of plasma estrogens, and as the androgens did not continue to fall with continuing dexamethasone treatment as did the estrogens, these findings also suggest that the decline in plasma estrogens is related in large part to suppression and atrophy of the fetal adrenals.


Asunto(s)
Androstenodiona/sangre , Dexametasona/farmacología , Hidrocortisona/sangre , Preñez/efectos de los fármacos , Testosterona/sangre , Animales , Depresión Química , Dexametasona/administración & dosificación , Estradiol/sangre , Estrona/sangre , Femenino , Macaca mulatta , Intercambio Materno-Fetal , Embarazo , Conejos/inmunología , Radioinmunoensayo , Factores de Tiempo , Tritio
13.
Endocrinology ; 125(4): 1766-73, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2791965

RESUMEN

The secretory response of the primate corpus luteum (CL) to CG after implantation suggests that gonadotropin receptors are not depleted despite increasing CG production and continuous elevated tropic stimulation. Such continuous stimulation is known to cause down-regulation of receptors in other tissues. To determine if CG secretion is intermittent during the initial stages of CL rescue, we assessed the secretory pattern of CG during the periimplantation period by collecting frequent (4/h) blood samples in two studies (for 4 h on 3 separate days between days 8-13, or for 2 separate 13-h sequences between days 10-15 postovulation) in 13 chair-adapted females. Day 0 of gestation was defined as the day of ovulation, as estimated by peak urinary estrone conjugate excretion in females mated on days 9, 11, and 13 of the menstrual cycle. Hormone concentrations were measured by either RIA [irFSH; estradiol and progesterone (P)] or Leydig cell bioassay (bioLH or bioCG). In the first study, 4 of 6 females conceived, and the mean for bioLH was not significantly elevated until days 12-13. In the second study, 5 of 7 females conceived, and the episodic secretory pattern of circulating pituitary bioLH typically observed in cycling females (2.7 +/- 0.3 peaks/13 h) was replaced by a relatively nonpulsatile, but steadily increasing profile during days 12-15 of gestation (1.5 +/- 0.4 peaks/13 h). Although occasional large fluctuations in bioLH/CG and P were noted, the bioLH/P peaks were less congruent than those in nonfertile cycles, and there was no diurnal pattern in the secretion of either hormone. In contrast, irFSH concentrations did not fluctuate and were similar in the two groups of females [2.93 +/- 0.28 vs. 2.34 +/- 1.7 ng/ml (mean +/- SEM)]. These data demonstrate that 1) a steady, gradually increasing secretory pattern of CG is associated with rescue of the CL; 2) the circulating profile of CG during the periimplantation interval is not consistently episodic and does not support the hypothesis that intermittent CG release prevents LH/CG receptor down-regulation in the CL during early pregnancy; 3) increased bioLH/CG levels during conceptive cycles in rhesus monkeys are not detected until days 12-13 after the midcycle bioLH peak; 4) irFSH patterns on pooled aliquots appear to be uninformative with regard to gonadotropin dynamics in early pregnancy; and 5) urinary estrone conjugate measurements provide a practical method for the precise timing of infrequent events, such as implantation, in the laboratory macaque.


Asunto(s)
Implantación del Embrión , Gonadotropinas/metabolismo , Macaca mulatta/fisiología , Macaca/fisiología , Animales , Estrona/orina , Estro/metabolismo , Femenino , Gonadotropinas/sangre , Hormona Luteinizante/metabolismo , Macaca mulatta/metabolismo , Concentración Osmolar , Embarazo/metabolismo , Flujo Pulsátil
14.
J Comp Neurol ; 164(1): 23-9, 1975 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-809493

RESUMEN

Radioautographic studies were conducted on early developmental stages of the inner ear in monkey (Macaca mulatta) embryos ranging in age from stage 11 to stage 20 (25 to 39 days' gestation) and labeled for one hour with [3H] thymidine. The most active period of proliferation occurred at stage 13, at which time all regions of the otocyst, including the endolymphatic duct, were heavily labeled. In subsequent stages the dorsal portion of the endolymphatic duct failed to incorporate label, whereas proliferation continued in the ventral portion of the duct near its communication with the medial wall of the otocyst. The duct thus appeared to grow upward as a result of cell division from below. Mitotic activity continued in the remainder of the otocyst although there was a progressive temporal decrease in the labeling index. Spatial gradients also occurred, with dorsal and lateral regions less active than ventral and medial ones. As the otocyst differentiated, the cells in various areas became attenuated. These flattened cells were still capable of undergoing cell division, as indicated by the presence of labeled nuclei in all regions of the utricle, saccule, semicircular ducts, and cochlear duct.


Asunto(s)
Oído Interno/embriología , Macaca mulatta/embriología , Macaca/embriología , Animales , División Celular , Cóclea/embriología , Haplorrinos , Sáculo y Utrículo/embriología , Canales Semicirculares/embriología
15.
Am J Clin Nutr ; 64(6): 908-15, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8942416

RESUMEN

Lethargy is characteristic of malnourished populations, but little is known about the biologic mechanism or consequences for cognitive performance. In the current experiment, 24-h activity patterns and performance of an attention task were studied in adolescent female monkeys (18-33 mo of age, n = 10/group) under conditions of moderate dietary zinc deprivation (2 micrograms Zn/g diet) and adequate dietary zinc (50 micrograms Zn/g). There were progressive decreases in daytime activity levels in the zinc-deprived group followed by slowing of growth around the time of the growth spurt. Attention performance was also impaired before the onset of growth retardation. Zinc-deprived monkeys failed to show the shift to later initiation of the rest phase of the diurnal cycle seen in controls in late adolescence. These data support previous findings that activity and attention can be affected during early stages of zinc deprivation before the onset of growth retardation.


Asunto(s)
Envejecimiento/fisiología , Conducta Animal/fisiología , Cognición/fisiología , Haplorrinos/fisiología , Zinc/deficiencia , Animales , Densidad Ósea/fisiología , Ritmo Circadiano/fisiología , Metabolismo Energético/fisiología , Femenino , Privación de Alimentos/fisiología , Trastornos del Crecimiento/fisiopatología , Trastornos del Crecimiento/veterinaria , Haplorrinos/sangre , Haplorrinos/crecimiento & desarrollo , Enfermedades de los Monos/fisiopatología , Descanso/fisiología , Maduración Sexual/fisiología , Privación de Agua/fisiología , Zinc/sangre , Zinc/fisiología
16.
Am J Clin Nutr ; 42(6): 1229-39, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4072958

RESUMEN

Rhesus monkey infants were marginally deprived of zinc (4 ppm diet) from conception and were compared to controls (100 ppm diet) during the first year of life in development of reflexes and motor patterns, mother-infant interaction, delayed response performance, discrimination learning and reversal, and open field behavior. Deficits in amount and variety of behavior were recorded in deprived infants; spontaneous locomotor activity was 50% below control levels in males at 1 mo of age; spontaneous activity was 7-10% lower in both males and females at 3 mo of age; response latencies were 50% lower than controls at 7-9 mo; failure to reach discrimination reversal criterion was seen in 71% of deprived infants as compared to 10% of controls at 10 mo of age; and abnormally low levels of climbing and exploration were seen in two of six deprived infants at 12 mo of age. No abnormalities in the rate of behavioral development or in emotional adaptability were observed. These and other results suggest that syndromes of lethargy, apathy, and hypoactivity are characteristic of behavioral effects of marginal zinc deprivation in primates.


Asunto(s)
Conducta Animal/fisiología , Zinc/deficiencia , Animales , Animales Recién Nacidos/fisiología , Peso Corporal , Aprendizaje Discriminativo/fisiología , Familia , Femenino , Macaca mulatta , Masculino , Actividad Motora/fisiología , Desempeño Psicomotor/fisiología
17.
Am J Clin Nutr ; 48(5): 1301-6, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3189220

RESUMEN

Low zinc bioavailability from soy formula may be the result of the formula's phytate content. We assessed the effect of phytate removal from soy formula on Zn absorption using infant rhesus monkeys and suckling rat pups as animal models. Zn absorption in monkeys, as determined by whole-body counting, was 65% from human milk, 54% from monkey milk, 60% from whey-predominant formula, 46% from casein-predominant formula, and only 27% from conventional soy formula (0.621 mmol phytate/L). In contrast, Zn absorption from dephytinized soy formula (0.067 mmol phytate/L) was 45%. In suckling rats, Zn absorption from conventional soy formula was only 16% vs 47% from dephytinized soy formula. Phytate concentration in a variety of experimental soy formulas was inversely correlated to Zn absorption. These results suggest that the low bioavailability of Zn from soy formula is a function of its phytate concentration and can be overcome by the removal of phytate.


Asunto(s)
Animales Recién Nacidos/metabolismo , Alimentos Infantiles , Ácido Fítico , Zinc/farmacocinética , Animales , Disponibilidad Biológica , Macaca mulatta , Ratas , Glycine max
18.
Am J Clin Nutr ; 45(6): 1503-13, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3591731

RESUMEN

Adult nonpregnant female rhesus monkeys fed purified diets containing 100 or 4 ppm zinc for 1 yr were mated then studied through midgestation. At mating, zinc-deprived (ZD) monkeys showed maternal lymphocyte response to mitogens concanavalin A (Con A) and phytohemagglutinin (PHA), serum uric acid and carbon dioxide, and WBC lower than in control (C) monkeys. There was a significant positive association between plasma zinc and PHA response. At midgestation, discriminant analysis revealed that maternal lymphocyte response to Con A, fetal abdominal circumference (by ultrasound), plasma fibrinogen, serum IgM, and amniotic fluid iron level were discriminators for diet group, all lower in ZD than in C monkeys. Maternal plasma and RBC zinc at midgestation were positively associated with fetal growth and plasma uric acid. These observations suggest that immune function (ie, mitogen response and serum immunoglobulin level) is a strong discriminator of dietary zinc deprivation in rhesus monkeys, both before and during pregnancy.


Asunto(s)
Desarrollo Embrionario y Fetal , Complicaciones del Embarazo/fisiopatología , Zinc/deficiencia , Animales , Peso Corporal , Ingestión de Alimentos , Femenino , Macaca mulatta , Embarazo , Complicaciones del Embarazo/inmunología , Complicaciones del Embarazo/metabolismo , Zinc/fisiología
19.
Am J Clin Nutr ; 47(6): 1046-51, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3376903

RESUMEN

Arrested adolescent growth and sexual maturation are striking symptoms of severe dietary zinc deprivation. More general implications of mild or marginal Zn deficiency during adolescence are not known. Five marginally Zn-deprived (ZD) male monkeys (4 mg Zn/kg diet) were compared with five controls pair fed a diet containing 100 mg Zn/kg during early adolescence. Mean plasma Zn levels were 38% lower in ZD group than in controls when evaluations began. During rapid growth plasma Zn decreased in controls but not ZD animals. ZD animals had delayed onset of accelerated weight gain and linear growth; loss of subcutaneous fat typical of early adolescence did not occur. ZD monkeys required two to three times more trials for both learning and reversal a visual discrimination task. Immune function was depressed 20-30% as reflected in early reduced proliferative response of peripheral lymphocytes and later lower immunoglobulin levels. Marginal dietary Zn deprivation affects growth and function in adolescence without producing frank developmental retardation.


Asunto(s)
Crecimiento , Maduración Sexual , Zinc/deficiencia , Envejecimiento/fisiología , Fosfatasa Alcalina/sangre , Animales , Peso Corporal , Cobre/sangre , Discriminación en Psicología/fisiología , Eritrocitos/metabolismo , Inmunoglobulina G/metabolismo , Aprendizaje/fisiología , Macaca mulatta , Masculino , Mitógenos/farmacología , Grosor de los Pliegues Cutáneos , Zinc/sangre
20.
Am J Clin Nutr ; 39(6): 879-87, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6539061

RESUMEN

A marginal state of zinc deficiency was induced in the pregnant nonhuman primate, Macaca mulatta, by feeding a diet containing 4 ppm zinc beginning at conception. Pregnancy outcome of marginally zinc-deficient monkeys (ZD) was compared to both pair-fed (PF) and ad libitum fed (AL) control animals (100 ppm zinc). Stillbirths, abortions, and delivery complications were more frequent in both ZD and PF dams than in AL controls; no malformations were detected (maternal plasma zinc was normal during organogenesis). Male ZD neonates weighed significantly less than same sex controls; also, in relation to colony norms, 7/8 ZD males, 2/8 ZD females, and 1/10 PF controls were of low birth weight. Further, plasma zinc and iron levels were lower in ZD neonates than in AL and PF controls. ZD neonates also had reduced muscle tonus. Birth weight and maternal plasma zinc concentration were negatively correlated in ZD group but positively correlated in AL and PF groups. Indeed, maternal plasma zinc concentration alone did not identify a state of zinc deficiency which impaired fetal growth in monkeys.


Asunto(s)
Complicaciones del Embarazo , Zinc/deficiencia , Aborto Espontáneo/etiología , Animales , Antropometría , Peso al Nacer , Dieta , Femenino , Muerte Fetal , Retardo del Crecimiento Fetal/etiología , Mortalidad Infantil , Macaca mulatta , Masculino , Examen Neurológico , Embarazo , Oligoelementos/sangre , Zinc/sangre
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