RESUMEN
Many species of yeast are integral to human society. They produce many of our foods, beverages and industrial chemicals, challenge us as pathogens, and provide models for the study of our own biology. However, few species are regularly studied and much of their ecology remains unclear, hindering the development of knowledge that is needed to improve the relationships between humans and yeasts. There is increasing evidence that insects are an essential component of ascomycetous yeast ecology. We propose a 'dispersal-encounter hypothesis' whereby yeasts are dispersed by insects between ephemeral, spatially disparate sugar resources, and insects, in turn, obtain the benefits of an honest signal from yeasts for the sugar resources. We review the relationship between yeasts and insects through three main examples: social wasps, social bees and beetles, with some additional examples from fruit flies. Ultimately, we suggest that over the next decades, consideration of these ecological and evolutionary relationships between insects and yeasts will allow prediction of where new yeast diversity is most likely to be discovered, particularly yeasts with traits of interest to human industry.
Asunto(s)
Ascomicetos/fisiología , Industria de Alimentos , Insectos/microbiología , Animales , Evolución Biológica , Ecosistema , Humanos , Néctar de las Plantas/metabolismo , SimbiosisRESUMEN
The power of citizen science to contribute to both science and society is gaining increased recognition, particularly in physics and biology. Although there is a long history of public engagement in agriculture and food science, the term 'citizen science' has rarely been applied to these efforts. Similarly, in the emerging field of citizen science, most new citizen science projects do not focus on food or agriculture. Here, we convened thought leaders from a broad range of fields related to citizen science, agriculture, and food science to highlight key opportunities for bridging these overlapping yet disconnected communities/fields and identify ways to leverage their respective strengths. Specifically, we show that (i) citizen science projects are addressing many grand challenges facing our food systems, as outlined by the United States National Institute of Food and Agriculture, as well as broader Sustainable Development Goals set by the United Nations Development Programme, (ii) there exist emerging opportunities and unique challenges for citizen science in agriculture/food research, and (iii) the greatest opportunities for the development of citizen science projects in agriculture and food science will be gained by using the existing infrastructure and tools of Extension programmes and through the engagement of urban communities. Further, we argue there is no better time to foster greater collaboration between these fields given the trend of shrinking Extension programmes, the increasing need to apply innovative solutions to address rising demands on agricultural systems, and the exponential growth of the field of citizen science.
Asunto(s)
Agricultura/tendencias , Participación de la Comunidad , Alimentos , Investigación/tendencias , Agricultura/normas , Investigación/normas , Estados UnidosRESUMEN
The ant genus Odontomachus Latreille in the United States is reviewed. Six species are treated: O. brunneus (Patton), O. clarus Roger, O. desertorum Wheeler stat. nov., O. relictus Deyrup and Cover, O. ruginodis M.R. Smith, and O. haematodus (Linnaeus), a new record for North America. The spread of O. haematodus is documented, and its identity is clarified. The genus is diagnosed for species in the Nearctic region for all castes, and worker- and male-based keys are presented. The workers and males of all six species are described and figured, including the first male descriptions for O. haematodus and O. desertorum. This represents the first study of species-level variation in Odontomachus male genitalia, and one of the first of such studies of the Ponerinae for any biogeographic region. A discussion of the utility of the male sex for Odontomachus taxonomy is provided.
Asunto(s)
Hormigas/anatomía & histología , Hormigas/clasificación , Animales , Femenino , Masculino , México , Estados UnidosRESUMEN
In this study, radiolabeled iodobenzovesamicol (IBVM), which is known to bind with high affinity to the vesicular acetylcholine transporter, was tested for its usefulness in imaging cortical cholinergic deficits in vivo. To induce reductions in cortical cholinergic input, the cholinergic immunotoxin 192IgG-saporin was employed. This has been shown to selectively and efficiently destroy basal forebrain cholinergic neurons in rats. The efficiency of the immunolesion was verified by histochemical acetylcholinesterase staining. [125I]-IBVM binding before and after lesioning was measured using autoradiography. Basal forebrain cholinergic cell loss resulted in a considerable reduction in [125I]-IBVM binding in the cholinoceptive target regions, but not in the striatum and cerebellum, brain regions that do not receive a cholinergic input by the basal forebrain cholinergic nuclei, suggesting that [123I]-IBVM has potential in imaging cortical cholinergic deficits in vivo, at least in animals.
Asunto(s)
Acetilcolinesterasa/deficiencia , Piperidinas/metabolismo , Prosencéfalo/metabolismo , Tetrahidronaftalenos/metabolismo , Acetilcolinesterasa/metabolismo , Análisis de Varianza , Animales , Autorradiografía , Fibras Colinérgicas/metabolismo , Femenino , Radioisótopos de Yodo , Piperidinas/farmacocinética , Prosencéfalo/diagnóstico por imagen , Prosencéfalo/patología , Radiografía , Ratas , Ratas Wistar , Receptores Colinérgicos/metabolismo , Receptores sigma/metabolismo , Tetrahidronaftalenos/farmacocinética , Distribución TisularRESUMEN
This study deals with the question of whether in vivo application of [125I]iodo-quinuclidinyl-benzilate (QNB) is able to demonstrate changes in cortical muscarinic receptor density induced by a cholinergic immunolesion of the rat basal forebrain cholinergic system, and whether the potential effects on IQNB distribution in vivo are also associated with effects on regional cerebral perfusion. Immunolesioned and control animals were injected with (R,S) [125]iodo-QNB and with [99mTc]-d,l-hexamethylpropyleneamine oxime (HMPAO). The cerebral distribution of both tracers was imaged using double tracer autoradiography. Impaired cholinergic transmission was paralleled by a 10-15% increase of [125I]iodo-QNB binding in the regions of cortex and hippocampus. The local cerebral blood flow remained unchanged after cholinergic lesion.
Asunto(s)
Acetilcolina/fisiología , Encéfalo/metabolismo , Circulación Cerebrovascular , N-Glicosil Hidrolasas , Quinuclidinil Bencilato/análogos & derivados , Receptores Muscarínicos/metabolismo , Acetilcolinesterasa/metabolismo , Animales , Desnervación Autonómica , Autorradiografía , Encéfalo/irrigación sanguínea , Corteza Cerebral/irrigación sanguínea , Corteza Cerebral/metabolismo , Hipocampo/irrigación sanguínea , Inmunotoxinas/farmacología , Radioisótopos de Yodo/metabolismo , Masculino , Proteínas de Plantas/farmacología , Prosencéfalo/fisiología , Quinuclidinil Bencilato/metabolismo , Ratas , Ratas Wistar , Flujo Sanguíneo Regional , Proteínas Inactivadoras de Ribosomas Tipo 1 , Saporinas , Exametazima de Tecnecio Tc 99m/metabolismoRESUMEN
PURPOSE: T-cell-located CD4 antigen represents one of the therapeutic targets in rheumatoid arthritis (RA). However, up to now there is no established imaging tool to visualize this target in vivo. The aim of our study was to assess the safety and tolerability of a technetium-99m labelled murine anti-human CD4 IgG1-Fab fragment ([(99m)Tc]-anti-CD4-Fab, [(99m)Tc]-EP1645) in patients with active synovitis due to RA, and to evaluate its potential as a marker of disease activity. METHODS: In the present phase I proof of principle study five patients with RA were examined. Planar scans of the whole body, hands, and feet were taken 30 min up to 24h after application of 550 ± 150 MBq [(99m)Tc]-anti-CD4-Fab, followed by visual analyses, comparison with clinical data in 68 joints per patient and semiquantitative analysis of hand and wrist joints. RESULTS: Neither infusion related adverse events nor adverse events during follow up were observed. No increase in human anti-murine antibody titres was seen. All patients had positive scans in almost 70% of clinically affected joints. Positive scans were also found in 8% of joints without evidence of swelling or tenderness. CONCLUSION: Scintigraphy with [(99m)Tc]-anti-CD4-Fab is a promising technique for evaluation of inflammatory activity in patients with RA, pre-therapeutical evaluation of CD4 status and therapy control. Tracer uptake in clinically inconspicuous joints strongly indicates diagnostic potential of [(99m)Tc]-anti-CD4-Fab. Whether this technique is eligible as a prognostic factor in RA needs to be analysed in further studies as well as the pathophysiological background of clinically affected joints lacking tracer uptake.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Artritis Reumatoide/diagnóstico por imagen , Antígenos CD4/inmunología , Tecnecio , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/farmacocinética , Femenino , Humanos , Inflamación/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Cintigrafía , SeguridadRESUMEN
Triacylglycerol (TAG) is the major storage component for fatty acids, and thus for energy, in eukaryotic cells. In this mini-review, we describe recent progress that has been made with the yeast Saccharomyces cerevisiae in understanding formation of TAG and its cell biological role. Formation of TAG involves the synthesis of phosphatidic acid (PA) and diacylglycerol (DAG), two key intermediates of lipid metabolism. De novo formation of PA in yeast as in other types of cells can occur either through the glycerol-3-phosphate- or dihydroxyacetone phosphate-pathways-each named after its respective precursor. PA, formed in two steps of acylation, is converted to DAG by phosphatidate phosphatase. Acylation of DAG to yield TAG is catalyzed mainly by the two yeast proteins Dga1p and Lro1p, which utilize acyl-CoA or phosphatidylcholine, respectively, as acyl donors. In addition, minor alternative routes of DAG acylation appear to exist. Endoplasmic reticulum and lipid particles (LP), the TAG storage compartment in yeast, are the major sites of TAG synthesis. The interplay of these organelles, formation of LP, and enzymatic properties of enzymes catalyzing the synthesis of PA, DAG, and TAG in yeast are discussed in this communication.
Asunto(s)
Saccharomyces cerevisiae/metabolismo , Triglicéridos/biosíntesis , Acilación , Aciltransferasas/metabolismo , Diacilglicerol O-Acetiltransferasa , Diglicéridos/metabolismo , Retículo Endoplásmico/metabolismo , Orgánulos/metabolismo , Ácidos Fosfatidicos/biosíntesis , Saccharomyces cerevisiae/enzimología , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
The absolute bioavailability of the digoxin tablet (dilanacin new) newly developed by the VEB Arzneimittelwerk Dresden is compared with the bioavailability of the old preparation, and it is referred to the clinical importance of the difference established. The determination of the absolute bioavailability was performed by radioimmunological concentration measurements in the serum and the urine, respectively, after single application of 0.5 and 1 mg, respectively, of the corresponding digoxin preparation (dilanacin intravenously, dilanacin and dilanacin new oral), in which cases 2 methods were applied: comparison of the surfaces below the curves of the serum levels of 0-48 h and the cumulative excretion of urine over 48 h. The typical courses of the serum levels in the different forms of application are figured and tabulated and interpreted. The results of the cumulative excretion of urine are differentiatedly explained in a table. According to the two methods corresponding results for the absolute bioavailability were achieved: 31 and 35%, respectively, for dilanacin and 62 and 67%, respectively, for dilanacin new. For the clinical practice an average oral maintenance dose of 0.25-0.375 mg/die is recommended for patients with healthy kidneys.
Asunto(s)
Digoxina/metabolismo , Administración Oral , Disponibilidad Biológica , Digoxina/administración & dosificación , Semivida , Humanos , Inyecciones Intravenosas , ComprimidosRESUMEN
The tested quality signs of the digoxin-RIA (Medica) correspond to other RIA-test methods. The digoxin-RIA (Medica) is, therefore, well suited for clinical examinations. In the dilanacin- (digoxin-) long-term therapy with the maintenance dose of 0.5 mg digoxin a day 75.4% of the patients examined (n = 65) were within the therapeutic field. In each case 12.3% were underdigitalised or overdigitalised, respectively. In the 8 patients in the toxic region only the half showed signs of digoxin intoxication. It is referred to the importance of creatinine and potassium in the serum, the digoxin clearance depending on age, the body weight and the body surface, respectively, in very obese patients for the height of the serum digoxin level and for the compatibility of this heart glycoside.
Asunto(s)
Digoxina/sangre , Radioinmunoensayo , Anciano , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The effect of different oral contraceptives with an estrogen content of 30-50 micrograms ethinyloestradiol on thyroid hormones and the binding protein TBG was investigated and quantified for 200 women. The sera of 220 normal persons were analysed to get normal values for T3, T4, FT4, Ft3, TBG and TSH. Under the influence of antiovulatory hormone treatment the thyroxin binding globulin increased to values above 32 mg/l in 65% of all euthyroid women. The median for T4 changed from 97 to 120 nmol/l, respectively from 2.3 to 2.8 nmol/l for T3. We think the combination of TSH, FT4 and T3 to be the best analytical tool for differential diagnosis of hyperthyreose. The FT4 level was nearly independent of variations in TBG concentration, so we can accept the normal range from 10-28 pmol/l for patients with contraceptives as well. In 16% of these euthyroid women the T3 level proved to be in the hyperthyroid range with values above 3.6 nmol/l. The FT3 determination is stronger influenced by protein changes caused by oestrogens than FT4 and should not be accepted as a favourite parameter for patients with oral contraceptives.
PIP: The effect of various contraceptives on thyroxin binding globulin (TBG) and the thyroid hormones T4 (thyroxin) and T3 (triiodothyronine) was investigated, and also whether the determination of the free hormones FT4 and FT3 meets expectations. The normal values of T3, T4, FT4, FT3, TBG, and TSH (thyroid-stimulating hormone) were ascertained in 220 people aged 18-70 years, (45% men and 55% women) by radiometric means. Thyroid function was studied in another group of 200 women aged 18-50 years who were taking various oral contraceptives (OCs) for at least 6 months. 107 euthyroid women not taking OCs served as controls. OCs used included Minisiston, Trisiston, Gravistat, Nonovlon, Sequostat, Ovosiston, and Deposiston. Patients were divided in euthyroid and hyperthyroid groups. T3, T4, and TSH determination was also verified in a group of 80 normal people. 65% of OC using euthyroid women had increased TBG levels, mostly under 50 mg/l. 23% of OC using euthyroid women had a T4 level of over 140 nmol/l and 27% had a T3 level above 3.3 nmol/1. Only 40% of women had both an elevated T4 and T3 level. TBG and total T4 and total T3 had weak correlation: coefficients of .33 and .21, respectively. In euthyroid OC users the median T4 values of 97 nmol/l shifted to 120 nmol/l, with the highest range of 140 nmol/l and 170 nmol/l. In euthyroid nonuser women the median T3 value was 2.3 nmol/l, increasing to 2.8 nmol/l in OC users. The average value of the TBG level with all OCs was in the range of 34-40 mg/l: it was over 50 mg/l in 13 cases, mostly with 50 mcg of ethinyl estradiol (EE). 21 hyperthyroid OC users had T3 values of 4 nmol/l and average TBG levels of 30.0 mg.l. In the diagnosis of hyperthyroidism in 90% of OC users the combination of basal TSH, FT4, and T3 can lead to clarification, provided a grey area of 4 nmol/l is accepted for T3. In the rest, TBG and FT3 determinations are also necessary.
Asunto(s)
Anticonceptivos Orales/efectos adversos , Hipertiroidismo/inducido químicamente , Pruebas de Función de la Tiroides , Tiroxina/sangre , Triyodotironina/sangre , Adolescente , Adulto , Anciano , Anticonceptivos Orales/administración & dosificación , Diagnóstico Diferencial , Femenino , Humanos , Hipertiroidismo/sangre , Persona de Mediana Edad , Valores de ReferenciaRESUMEN
Acinetobacter calcoaceticus growing on long-chain n-alkanes contains a soluble iron-sulfur protein, which corresponds in its properties to a rubredoxin. It was prepared from the 50000 X g supernatant of ultrasonically treated cells using ion exchange chromatography on DEAE cellulose and gel filtration on Sephadex G-75. The isolated protein is pure electrophoretically, but yields two bands corresponding to molecular weights of 6000 and 12000 respectively. A content of 11 acidic against 6 basic amino acids is in line with the acidic character of the protein. The absence of acid-labile sulfur, content of 4 cysteine residues and one iron atom per polypeptide chain and the typical absorption maxima at gamma = 280, 380, and 490 nm exclude the presence of a ferredoxin. Involvement of the rubredoxin in the alkane hydroxylation is discussed.
Asunto(s)
Acinetobacter/metabolismo , Ferredoxinas/aislamiento & purificación , Rubredoxinas/aislamiento & purificación , Aminoácidos/análisis , Peso Molecular , Oxidación-Reducción , Rubredoxinas/metabolismo , Espectrofotometría , Espectrofotometría UltravioletaRESUMEN
In 14 patients with short stature aged 4-14 years the effect of clonidine has been investigated. A single oral dose of 0.15 mg/m2 surface area is followed by a marked increase of hGH concentration in blood with a peak value between 60 and 90 min after the administration of the drug. The hGH increase caused by clonidine was comparable to the rise during insulin-induced hypoglycemia. In 5 patients both stimuli failed to increase hGH release. The test procedure is simple. It shows only minimum side effects and can therefore be especially recommended in outpatients.
Asunto(s)
Estatura , Clonidina/uso terapéutico , Hormona del Crecimiento/sangre , Adolescente , Niño , Preescolar , Humanos , Hipoglucemia/sangreRESUMEN
Disturbances of the vitamin B12 resorption by the therapy with biguanides above all metformin are known from literature. In 59 patients with Buformin retard-monotherapy we determined in 18.7% slight reductions of the vitamin B12 level in the serum, in one patient the serum concentration was lower than 50 pg/ml. That means that also under therapy with Buformin can be reckoned with easy disturbances of resorption for vitamin B12. Occasional controls of Hb and anamnestic establishment of neurological symptoms are to be recommended during a therapy with Buformin, in order not to overlook the clinical signs of a vitamin B12 hypovitaminosis.
Asunto(s)
Biguanidas/efectos adversos , Buformina/efectos adversos , Buformina/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Femenino , Humanos , Absorción Intestinal/efectos de los fármacos , Masculino , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/inducido químicamenteRESUMEN
Total testosterone concentrations in the serum of patients treated with antiandrogens were measured by means of an industrially produced radioimmunological testosterone assay kit (VEB Sächsisches Serumwerk Dresden). Antiandrogen therapy using cyproterone acetate (Androcur) leads to a reduction in serum testosterone concentration which is significant at the p less than 0.01 level. The data suggest that testosterone concentrations vary inversely with increasing Androcur dosage; they are around 7 nmol/l at the doses conventionally administered. The testosterone concentrations obtained under depot-Androcur treatment suggest that intervals between injections should be less than 10 days.
Asunto(s)
Ciproterona/análogos & derivados , Trastornos Parafílicos/tratamiento farmacológico , Testosterona/sangre , Adolescente , Adulto , Anciano , Ciproterona/uso terapéutico , Acetato de Ciproterona , Alemania Oriental , Humanos , Masculino , Persona de Mediana Edad , Trastornos Parafílicos/sangreRESUMEN
The influence on the parameters of the thyroid gland BEI, T3-, T4- and TSH-serum level by the iodine-containing oral bile X-ray contrast remedy Falignost is demonstrated. Following a peripheral conversions inhibition from T4 to T3 by the contrast remedy the thyroid hormones in the serum are changed in different kind and duration. This influence is more expressed in patients with liver cirrhosis and continues. The risk of an iodine-induced hyperthyroidism is discussed. In the judgment of a possible disturbance of the function of the thyroid gland anamnestically is always to be asked the question about previous applications of iodine-containing drugs and it must be accordingly be taken into consideration.
Asunto(s)
Medios de Contraste/efectos adversos , Yodobencenos/efectos adversos , Pruebas de Función de la Tiroides/métodos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Cirrosis Hepática/sangre , Masculino , Estudios Prospectivos , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Triyodotironina Inversa/sangreRESUMEN
In a 28 year-old man with epigastric pain endoscopy detected giant gastric folds and multiple superficial erosions. Histologically a mixed form of glandular and foveolar hyper plasia of the gastric mucosa was suggested (Ming's type III). Basal and pentagastrin stimulated secretion volume and acid output were moderately elevated, hypersecretion of protein was not found. Serum levels of calcium and gastrin were normal, also after secretin stimulation. The mucosa of the corpus was extensively infested with Campylobacter pylori. Therapy with cimetidine, antacids, pirenzepine and metronidazol resulted in relief of symptoms but not of histological findings. Bismuth (JatroxR) was successful in eradicating Campylobacter pylori and decreasing inflammation of the mucosa. Cause and prognosis of this mixed hyperplasia are not known.
Asunto(s)
Infecciones por Campylobacter/patología , Mucosa Gástrica/patología , Gastritis Hipertrófica/patología , Adulto , Epitelio/patología , Determinación de la Acidez Gástrica , Gastroscopía , Humanos , Masculino , Antro Pilórico/patologíaRESUMEN
Carcinomas were induced to the thyroid gland of female rats, using a method originally proposed by Thomas and Bollmann (metachronous application of nitrosomethylurea and methylthiouracil), to establish cytomorphological, histomorphological, cytochemical, and flow-cytophotometric criteria for diagnosis of thyroid carcinoma. Verification was also intended of the diagnostic value of each of the methods involved for differentiation of nodular goitre. Another purpose of the study was to find out, whether chemically induced thyroid tumours in rat were comparable to thyroid neoplasms in man. This provided to the examiners genetically coherent and morphologically comparable biological material at various stages of thyroid tumour growth which included diffuse and adenomatous hyperplasias, adenomas, and, from the 18th to 42nd experimental weeks, papillary as well as follicular carcinomas in 31 to 100% of all experimental animals involved. Cytomorphological comparability of rat thyroid material (imprint specimens) with human material (fine-needle aspiration cytology) was ensured for normal as well as for hyperplastically altered thyroid glands, including adenomatous and carcinomatous changes. Hence, group typing of thyroid cytology, originally devised for human specimens, could be easily adapted to material obtained from rat. Assessment of cytological samples by microscopic criteria yielded an accuracy of 89% in malignoma diagnosis and proved to be an approach of highly informative potential also in the context of rat experiments. Use of additional cytochemical techniques (PAS, toluidine-blue, peroxidase, alkaline and acid phosphatases, gamma-glutamyl transpeptidase) as well as quantitative DNA determination by means of flow-cytophotometry was helpful in casting light at some scattered trends of change from normal for certain stages of proliferation, but it failed to enhance information in cytomorphological diagnosis of the individual case.
Asunto(s)
Adenocarcinoma/patología , Adenoma/patología , Carcinoma Papilar/patología , Neoplasias de la Tiroides/patología , Adenocarcinoma/diagnóstico , Adenoma/diagnóstico , Animales , Carcinoma Papilar/diagnóstico , Citofotometría , ADN de Neoplasias/análisis , Diagnóstico Diferencial , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Citometría de Flujo , Histocitoquímica , Hiperplasia , Valor Predictivo de las Pruebas , Ratas , Ratas Endogámicas , Neoplasias de la Tiroides/diagnósticoRESUMEN
20 patients with hyperthyroidism were observed with repeated EEG measurements before and during treatment (ObsidanR; MethimazolR). 17 patients, before starting antithyroid therapy, had slight to moderate EEG abnormalities. A prevalence for moderate disturbances occurred for patients with a higher degree of hyperthyroidism. The dominant EEG frequency was higher than in euthyroid controls, but no exact correlation to T3-values could be observed. 16 patients showed abnormal reactivity to photic stimulation. One-week therapy by propranolol produced only a slight synchronizing effect in EEG's, where T3-values decreased. After 4 weeks selective therapy by MethimazolR all patients were euthyroid, but some EEG abnormalities persisted in 12 patients in a lower degree. The dominant EEG frequency decreased to control-group ranges and abnormal photic reactivity was reduced. After 6 months some EEG disturbances re-increased tentiatively, in 3 relapses excessively. These observations confirm the prognostic value of EEG measurements for the recognition of occurrence and persistence of cerebral disturbances in severe metabolic dysfunctions.