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2.
Proc Biol Sci ; 287(1931): 20200922, 2020 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-33043867

RESUMEN

Most of the world's crops depend on pollinators, so declines in both managed and wild bees raise concerns about food security. However, the degree to which insect pollination is actually limiting current crop production is poorly understood, as is the role of wild species (as opposed to managed honeybees) in pollinating crops, particularly in intensive production areas. We established a nationwide study to assess the extent of pollinator limitation in seven crops at 131 locations situated across major crop-producing areas of the USA. We found that five out of seven crops showed evidence of pollinator limitation. Wild bees and honeybees provided comparable amounts of pollination for most crops, even in agriculturally intensive regions. We estimated the nationwide annual production value of wild pollinators to the seven crops we studied at over $1.5 billion; the value of wild bee pollination of all pollinator-dependent crops would be much greater. Our findings show that pollinator declines could translate directly into decreased yields or production for most of the crops studied, and that wild species contribute substantially to pollination of most study crops in major crop-producing regions.


Asunto(s)
Agricultura , Productos Agrícolas , Polinización , Animales , Abejas , Abastecimiento de Alimentos , Estados Unidos
3.
Anaesth Intensive Care ; 46(5): 463-467, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30189819

RESUMEN

Prolonged fasting leads to a shift from carbohydrate to fat as the primary energy source, resulting in the production of ketones such as beta-hydroxybutyrate. Hyperketonaemia and ketoacidosis have been observed in young children fasting for surgery. The aim of this study was to investigate ketonaemia in adults fasted for surgery. One hundred non-diabetic adults presenting for elective or emergency surgery were assessed for the presence of hyperketonaemia (beta-hydroxybutyrate levels more than 1 mmol/l), and the relationship between beta-hydroxybutyrate, blood glucose and fasting duration was investigated. Three of 100 patients demonstrated hyperketonaemia, one of whom had ingested a ketogenic supplement the evening prior to surgery. No patient demonstrated beta-hydroxybutyrate levels suggestive of ketoacidosis (above 3 mmol/l). No relationship between fasting duration and ketone or glucose levels was observed. We found no evidence that prolonged preoperative fasting led to beta-hydroxybutyrate levels consistent with ketoacidosis.


Asunto(s)
Ayuno , Cuerpos Cetónicos/sangre , Cuidados Preoperatorios , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos Electivos , Urgencias Médicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Centros de Atención Terciaria , Adulto Joven
4.
Psychol Med ; 45(15): 3217-26, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26096463

RESUMEN

BACKGROUND: Glucocorticoids and serotonin may mediate the link between maternal environment, fetal brain development and 'programming' of offspring behaviors. The placenta regulates fetal exposure to maternal hormonal signals in animal studies, but few data address this in humans. We measured prospectively maternal depressive symptoms during pregnancy and mRNAs encoding key gene products determining glucocorticoid and serotonin function in term human placenta and explored associations with infant regulatory behaviors. METHOD: Bi-weekly self-ratings of the Center for Epidemiologic Studies Depression Scale from 12th to 13th gestational week onwards and term placental mRNAs of 11beta-hydroxysteroid dehydrogenase type 2 (HSD2B11), type 1 (HSD1B11), glucocorticoid (NR3C1), mineralocorticoid receptors (NR3C2) and serotonin transporter (SLC6A4) were obtained from 54 healthy mothers aged 32.2 ± 5.3 years with singleton pregnancies and without pregnancy complications. Infant regulatory behaviors (crying, feeding, spitting, elimination, sleeping and predictability) were mother-rated at 15.6 ± 4.2 days. RESULTS: Higher placental mRNA levels of HSD2B11 [0.41 standard deviation (s.d.) unit increase per s.d. unit increase; 95% confidence interval (CI) 0.13-0.69, p = 0.005], HSD1B11 (0.30, 0.03-0.57, p = 0.03), NR3C1 (0.44, 0.19-0.68, p = 0.001) and SLC6A4 (0.26, 0.00-0.53, p = 0.05) were associated with more regulatory behavioral challenges of the infant. Higher placental NR3C1 mRNA partly mediated the association between maternal depressive symptoms during pregnancy and infant regulatory behaviors (p < 0.05). CONCLUSIONS: Higher placental expression of genes regulating feto-placental glucocorticoid and serotonin exposure is characteristic of infants with more regulatory behavioral challenges. Maternal depression acts, at least partly, via altering glucocorticoid action in the placenta to impact on offspring regulatory behaviors.


Asunto(s)
Depresión/metabolismo , Glucocorticoides/metabolismo , Conducta del Lactante/fisiología , Placenta/metabolismo , Complicaciones del Embarazo/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Problema de Conducta , Serotonina/metabolismo , Adulto , Femenino , Estudios de Seguimiento , Expresión Génica , Glucocorticoides/genética , Humanos , Lactante , Masculino , Embarazo , ARN Mensajero/metabolismo , Serotonina/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo
5.
Psychol Med ; 45(10): 2023-30, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25628053

RESUMEN

BACKGROUND: Maternal prenatal depression predicts post-partum depression and increases risk of prematurity and low birth weight. These effects may be mediated by altered placental function. We hypothesized that placental function would be influenced by the gestational week of experiencing depressive symptoms and aimed to examine associations between maternal depressive symptoms during pregnancy and placental expression of genes involved in glucocorticoid and serotonin transfer between mother and fetus. METHOD: We studied women participating in a prospective pregnancy cohort: the Prediction and Prevention of Preeclampsia (PREDO) Study, Helsinki, Finland. Maternal depressive symptoms were assessed at 2-week intervals throughout pregnancy in 56 healthy women with singleton, term pregnancies. Messenger ribonucleic acid (mRNA) levels of glucocorticoid (GR) and mineralocorticoid (MR) receptors and serotonin transporter (SLC6A4), 11ß-hydroxysteroid dehydrogenase type 1 (HSD1) and 2 (HSD2) were quantified in placental biopsies. RESULTS: In adjusted analyses women who reported higher depressive symptoms across the whole pregnancy had higher mRNA levels of GR [effect size 0.31 s.d. units, 95% confidence interval (CI) 0.01-0.60, p = 0.042] and MR (effect size 0.34 s.d. units, 95% CI 0.01-0.68, p = 0.047). These effects were significant for symptoms experienced in the third trimester of pregnancy for GR; findings for MR were also significant for symptoms experienced in the second trimester. GR and MR mRNA levels increased linearly by having the trimester-specific depressive symptoms scores 0, 1 or 2-3 times above the clinical cut-off for depression (p = 0.003, p = 0.049, respectively, and p = 0.004, p = 0.15 in adjusted analyses). CONCLUSIONS: Our findings offer potential gestational-age-specific mechanisms linking maternal depressive symptoms during pregnancy via placental biology. Future studies will test whether these also link with adverse offspring outcomes.


Asunto(s)
Depresión/fisiopatología , Glucocorticoides/metabolismo , Complicaciones del Embarazo/fisiopatología , ARN Mensajero/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasas/análisis , Adulto , Femenino , Finlandia , Glucocorticoides/genética , Humanos , Modelos Lineales , Placenta/química , Embarazo , Trimestres del Embarazo , Escalas de Valoración Psiquiátrica , ARN Mensajero/análisis , ARN Mensajero/genética , Receptores de Mineralocorticoides/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas de Transporte de Serotonina en la Membrana Plasmática/análisis , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Adulto Joven
6.
Pregnancy Hypertens ; 4(3): 238, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26104631

RESUMEN

BACKGROUND: The hypothalamic-pituitary-adrenal (HPA) axis is important for fetal growth and timing of parturition. Maternal obesity is associated with macrosomia (birthweight ⩾4000g) and prolonged pregnancy (⩾41weeks). We aimed to characterise HPA axis hormones in obese pregnancy and to test associations with these pregnancy outcomes. METHOD: Fasting cortisol was measured by radioimmunoassay in venous blood at 16, 28 and 36 weeks of gestation in 286 obese (BMI 44.05±3.98kg/m(2)) and 137 lean (BMI 22.71±1.66kg/m(2)) pregnant women. In subsets (n=20 obese, 20 lean) we measured corticosteroid binding globulin (CBG) and CRH by radioimmunoassay; progesterone, estradiol (E2), estriol (E3) and sex-hormone-binding-globulin (SHBG) by ELISA; and albumin by bromocresol green binding. Free cortisol levels were calculated using Coolen's equation. RESULTS: Cortisol, CBG, calculated free cortisol, CRH, E2, E3, progesterone and SHBG levels rose similarly during pregnancy in obese and lean, but were significantly lower in obese (p<0.05). In obese, lower free cortisol at 16 weeks was associated with higher birthweight (r=-0.46, p<0.05). Cortisol was not associated with labour onset. CRH was significantly lower at 36 weeks in women who delivered at ⩾41weeks and in women with macrosomic babies (p<0.05); and correlated negatively with gestation at delivery in obese (r=-0.557, p<0.05). CONCLUSION: Our findings suggest that decreased HPA axis activity in obese pregnancy may be a mechanism underlying macrosomia and prolonged pregnancy.

7.
Head Neck ; 14(5): 415-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1399578

RESUMEN

The consultants agreed that the differential diagnosis should focus on congenital masses, including an encephalocele, glioma, dermoid, hamartoma, hemangioma, rhabdomyosarcoma, neurofibroma, and nasolacrimal duct cyst. There was some disagreement as to which is the best way to evaluate the mass, ranging from an MRI (Dr. Reilly), to CT scan (Dr. Cotton), to both MRI and CT (Dr. Koopman). Blood tests to evaluate pituitary function could be indicated if there was a sphenoid defect (Dr. Reilly). None of the experts would biopsy this lesion. All would proceed with a definitive resection. One surgeon would defer surgery for several months and then perform the resection via a biocoronal craniotomy (Dr. Reilly). A combined anterior craniotomy and external ethmoidectomy would be planned by another (Dr. Koopman). The third consultant would combine an anterior craniotomy with a mid-face degloving, external rhinoplasty, or lateral rhinotomy approach (Dr. Cotton). Routine perioperative antibiotics would only be used by two of the surgeons (Drs. Reilly and Koopman). If a CSF leak were encountered there are several options. A small lesion could be allowed to close on its own (Dr. Reilly). If the leak occurred while the bicoronal incision was still open or if the leak were large, it could be repaired from above (Drs. Reilly and Koopman). One surgeon would proceed with a repair from above even if the leak were encountered during the intranasal approach (Dr. Cotton). Only one surgeon would restrict postoperative activity with intubation and sedation or paralysis (Dr. Koopman). Regarding follow-up, no one was concerned about the final pathology report.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Encéfalo , Coristoma/diagnóstico , Neoplasias Nasales/diagnóstico , Coristoma/cirugía , Diagnóstico Diferencial , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Neoplasias Nasales/cirugía , Cuidados Posoperatorios , Procedimientos Quirúrgicos Operativos/métodos , Tomografía Computarizada por Rayos X
8.
Am J Surg ; 163(4): 413-6, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1532700

RESUMEN

Over a 5-year period, iliopsoas abscesses were found in 11 patients. Although the most common underlying condition was Crohn's disease (3 of 11 patients), 5 abscesses resulted from hematogenous spread from a distant site. Each of these five patients was elderly, severely malnourished, or had an underlying chronic disease. Fever was a presenting sign in 8 of 11 patients, whereas all 4 patients who presented with back pain had nontuberculous lumbar osteomyelitis or disk space infections. No patient presented with the classic triad of fever, back pain, and anterior thigh or groin pain. Computed tomographic (CT) scans accurately established the clinical diagnosis in 10 of 11 patients. Two of the patients died. One patient was an intravenous drug abuser, whereas the other patient was being treated with steroids for systemic lupus erythematosus. Elderly patients, diabetics, and patients with chronic disease are susceptible to this kind of occult infection and may present with minimal clinical findings. Aggressive diagnosis using CT scanning and treatment with resection of involved bowel, complete drainage of the abscess, and prolonged antibiotics are required to salvage these patients.


Asunto(s)
Absceso del Psoas/etiología , Absceso/complicaciones , Adulto , Anciano , Dolor de Espalda/etiología , Enfermedad Crónica , Femenino , Fiebre/etiología , Enfermedades Gastrointestinales/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Próstata/complicaciones , Absceso del Psoas/complicaciones , Absceso del Psoas/diagnóstico , Absceso del Psoas/terapia , Abuso de Sustancias por Vía Intravenosa/complicaciones , Tuberculosis de la Columna Vertebral/complicaciones
9.
Eur J Drug Metab Pharmacokinet ; Spec No 3: 116-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1820864

RESUMEN

All simple micellar systems investigated, containing both naturally occurring and synthetic surfactants, enhanced the solubility of clofazimine. The incorporation of fatty acid to form mixed micelles, brought about a further enhancement in drug solubility in the case of naturally occurring surfactants, in contrast, with synthetic surfactants this enhancement decreased. The most effective absorption promoter was a synthetic surfactant: fatty acid mixed micellar system. The results indicate an optimum surfactant: fatty acid ratio at which the solubility and membrane effects of the surfactant system are balanced.


Asunto(s)
Clofazimina/química , Tensoactivos/química , Absorción/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Micelas , Permeabilidad , Solubilidad , Espectrofotometría Ultravioleta
11.
J Wildl Dis ; 6(4): 289-94, 1970 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16512129

RESUMEN

Five species of wild animals including opossums, Didelphis marsupialis, striped skunks, Mephitis mephitis, red, Vulpes vulpes, and gray foxes, Urocyon cinereoargenteus and raccoons, Procyon lotor, were inoculated intraperitoneally with varying numbers of Leptospira grippotyphosa, organisms. Clinical signs were not detected, however, leptospiremia, leptospiruria and antibodies for the homologous organism, were demonstrated. Lesions attributed to leptospirosis were observed in liver and kidney tissue of infected animals. Infections were demonstrated in 5 of 9 opossums, 3 of 9 striped skunks, 3 of 9 red foxes, none of the gray foxes, and 9 of 9 raccoons. Therefore, it would appear that under conditions of this experiment that raccoons were most, opossums moderately, and skunks and red foxes least susceptible; gray foxes were not susceptible.


Asunto(s)
Animales Salvajes/microbiología , Susceptibilidad a Enfermedades/veterinaria , Leptospira/patogenicidad , Leptospirosis/veterinaria , Animales , Femenino , Zorros , Leptospirosis/inmunología , Leptospirosis/patología , Masculino , Mephitidae , Zarigüeyas , Mapaches , Especificidad de la Especie
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