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1.
Ergonomics ; 66(8): 1142-1163, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36259259

RESUMEN

There is a variety of visual human-machine interfaces (HMI) designed across vehicle manufacturers that support drivers while supervising driving automation features, such as adaptive cruise control (ACC). These various designs communicate the same limited amount of information to drivers about their ACC system and it is unclear which HMI designs impact driver distraction the least or how their design could be modified to help drivers develop more accurate mental models of their ACC system. Using a user-centred design (UCD) approach, we designed a speedometer to inform drivers about some of the system's capabilities and then invited 23 drivers to use ACC in a low-fidelity driving simulator to compare the usability of three HMIs using eye-tracking, response times, and qualitative data. Our attempt at designing an intuitive and more informative speedometer received mixed results, but design recommendations are given regarding the indication of the set target speed, set time gap between vehicles (headway distance), and system mode (conventional or adaptive cruise). Practitioner summary: Manufacturers' heterogeneous designs of their visual HMIs for the ACC systems may impact driver distraction in different ways. We used usability testing to compare three HMIs in a driving simulator and make several design recommendations to indicate speed, time gap, and system mode in a more efficient way. Abbreviations: ACC: adaptive cruise control; ADAS: advanced driving assistance system; HMI: human-machine interface; ISO: international organisation for standardization; OEM: original equipment manufacturer; RSME: rating scale of mental effort; RT: response time; R-TLX: raw task load index; SUS: system usability scale; TGT: total glance time; UCD: user-centred design; UX: user experience; xTGT: extended total glance time.


Asunto(s)
Conducción de Automóvil , Conducción Distraída , Humanos , Diseño Centrado en el Usuario , Interfaz Usuario-Computador , Tiempo de Reacción , Automatización , Accidentes de Tránsito
2.
J Econ Entomol ; 109(2): 684-98, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26896532

RESUMEN

The western corn rootworm, Diabrotica virgifera virgifera LeConte, is the most important insect of maize, Zea mays L., but knowledge of its interaction with water deficit on maize production is lacking. A series of greenhouse experiments using three infestation levels of the western corn rootworm, D. virgifera virgifera, under well-watered, moderately dry, and very dry soil moisture levels were conducted to quantify the interaction of western corn rootworm and soil water deficit on B73×Mo17 maize growth and physiology. Three separate experiments were conducted. Soil moisture regimes were initiated 30 d postplanting for experiments using neonate and second-instar larvae and 30 d postinfestation in the experiment using eggs. In the neonate and second-instar experiments, there were no significant differences among western corn rootworm levels in their effects on leaf water potential, shoot dry weight, and root dry weight. The interaction of western corn rootworm and soil moisture significantly impacted the larval recovery in the neonate experiment, but no other significant interactions were documented between soil moisture levels and rootworm infestation levels. Overall, the results indicate that under the conditions of these experiments, the effect of water deficit was much greater on plants than the effect of western corn rootworm and that the interactions between water deficit and western corn rootworm levels minimally affected the measured parameters of plant performance.


Asunto(s)
Escarabajos/fisiología , Sequías , Agua/fisiología , Zea mays/crecimiento & desarrollo , Animales , Larva/fisiología , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/crecimiento & desarrollo , Estomas de Plantas/fisiología
3.
Perit Dial Int ; : 8968608241270294, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105257

RESUMEN

Automation has allowed clinicians to program PD treatment parameters, all while obtaining extensive individual treatment data. This data populates in a centralized online platform shortly after PD treatment completion. Individual treatment data available to providers includes patients' vital signs, alarms, bypasses, prescribed PD treatment, actual treatment length, individual cycle fill volumes, ultrafiltration volumes, as well as fill, dwell, and drain times. However, there is no guidance about how often or if this data should be assessed by the clinical team members. We set out to determine current practice patterns by surveying members of the home dialysis team managing PD patients across the United States and Canada. A total of 127 providers completed the survey. While 91% of respondents reported having access to a remote monitoring platform, only 31% reported having a standardized protocol for data monitoring. Rating their perceived importance of having a standard protocol for remote data monitoring, on a scale of 0 (not important at all) to 10 (extremely important), the average response was 8 (physicians 7; nurses 9). Most nurses reported reviewing the data multiple times per week, whereas most physicians reported viewing the data only during regular/monthly visits. Although most of the providers who responded have access to remote monitoring data and feel that regular review is important, the degree of its utilization is variable, and the way in which the information is used is not commonly protocolized. Working to standardize data interpretation, testing algorithms, and educating providers to help process and present the data are important next steps.

4.
Science ; 237(4813): 389-94, 1987 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-17794341

RESUMEN

The proposed role of the 30-kilodalton(kD) protein of tobacco mosaic virus is to facilitate cell-to-cell spread of the virus-during infection. To directly define the function of the protein, a chimeric gene containing a cloned complementary DNA of the 30-kD protein gene was introduced into tobacco cells via a Ti plasmid-mediated transformation system of Agrobacterium tumefaciens. Transgenic plants regenerated from transformed tobacco cells expressed the 30-kD protein messenger RNA and accumulated 30-kD protein. Seedlings expressing the 30-kD protein gene complemented the Lsl mutant of TMV, a mutant that is temperature-sensitive in cell-to-cell movement. In addition, enhanced movement of the Lsl virus at the permissive temperature was detected in seedlings that express the 30-kD protein gene. These results conclusively demonstrate that the 30-kD protein of tobacco mosaic virus potentiates the movement of the virus from cell to cell.

5.
J Vasc Access ; 9(2): 122-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18609528

RESUMEN

BACKGROUND: The use of central venous catheters for vascular access in hemodialysis (HD) patients is associated with an increased risk of complications compared to arteriovenous fistulas (AVF). Despite this, catheter use remains high and patient satisfaction may be an important driver of catheter use. METHODS: We developed the Vascular Access Questionnaire (VAQ) to measure patient-reported views of their vascular access. Chronic HD patients at two centers were asked to rate how bothered they were by 17 access-related problems. VAQ symptom scores were compared between patients using catheters and those using fistulas for vascular access. RESULTS: Two hundred and twenty-two patients were eligible for the study. Symptom score was not different between patients using catheters and those using fistulas (p=0.36). However, patients using fistulas were more likely to be at least moderately bothered by pain, bleeding, bruising, swelling, and the appearance of their access than patients using catheters. Elderly patients reported lower symptom scores with catheters than fistulas. CONCLUSIONS: Patients appear to be primarily concerned with the appearance of their access and cannulation-related complications, particularly the elderly. Better education about the risk of adverse events with catheters and the implementation of measures aimed at reducing cannulation-related complications may help to increase fistula rates and improve patient satisfaction with their vascular access.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/psicología , Cateterismo Venoso Central/psicología , Satisfacción del Paciente , Diálisis Renal/psicología , Encuestas y Cuestionarios , Anciano , Derivación Arteriovenosa Quirúrgica/efectos adversos , Cateterismo Venoso Central/efectos adversos , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Diálisis Renal/efectos adversos
6.
J Econ Entomol ; 111(1): 193-208, 2018 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-29190344

RESUMEN

Anecdotal data in the past have suggested that the effect of the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), on maize yield is greater under drought and the effect of drought is greater under rootworm infestations, but no field experiments have controlled both moisture and rootworm levels. Field studies were conducted in 2012, 2013, and 2014 with treatments in a factorial arrangement of western corn rootworm infestation levels, and maize hybrids (with and without tolerance to drought and rootworm feeding). The experiment was repeated under well-watered and drought conditions in adjacent plots. Leaf water potential and stomatal conductance data suggested significant plant stress was achieved in the drought plots toward the end of the season each year and maize hybrids only played a minor role. In particular, in 2012 and 2013 yield was dramatically lower for the drought experiment than for the well-watered experiment. However, the impacts of rootworm infestation level and maize hybrids on water potential, stomatal conductance, and yield were variable across years and between experiments. In fact, the only year that the main effect of rootworm infestation levels significantly impacted yield was in 2014, when an extremely high infestation level was added and this was only for the well-watered portion of the experiment. Overall, rootworm infestation level played a relatively minor role in maize productivity and it did not appear that soil moisture level influenced that to a large degree.


Asunto(s)
Antibiosis , Escarabajos/fisiología , Sequías , Herbivoria , Zea mays/fisiología , Animales , Escarabajos/crecimiento & desarrollo , Hibridación Genética , Larva/fisiología , Missouri , Distribución Aleatoria , Estrés Fisiológico , Zea mays/genética
7.
Accid Anal Prev ; 96: 39-45, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27497055

RESUMEN

The influence of driver distraction on driving performance is not yet well understood, but it can have detrimental effects on road safety. In this study, we examined the effects of visual and non-visual distractions during driving, using a high-fidelity driving simulator. The visual task was presented either at an offset angle on an in-vehicle screen, or on the back of a moving lead vehicle. Similar to results from previous studies in this area, non-visual (cognitive) distraction resulted in improved lane keeping performance and increased gaze concentration towards the centre of the road, compared to baseline driving, and further examination of the steering control metrics indicated an increase in steering wheel reversal rates, steering wheel acceleration, and steering entropy. We show, for the first time, that when the visual task is presented centrally, drivers' lane deviation reduces (similar to non-visual distraction), whilst measures of steering control, overall, indicated more steering activity, compared to baseline. When using a visual task that required the diversion of gaze to an in-vehicle display, but without a manual element, lane keeping performance was similar to baseline driving. Steering wheel reversal rates were found to adequately tease apart the effects of non-visual distraction (increase of 0.5° reversals) and visual distraction with offset gaze direction (increase of 2.5° reversals). These findings are discussed in terms of steering control during different types of in-vehicle distraction, and the possible role of manual interference by distracting secondary tasks.


Asunto(s)
Atención , Conducción de Automóvil/psicología , Conducción Distraída/psicología , Movimientos Oculares/fisiología , Seguridad , Aceleración , Cognición , Femenino , Humanos , Masculino , Percepción Visual , Adulto Joven
8.
Plant Physiol ; 102(1): 295-302, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-12231821

RESUMEN

Analysis of the temperatures providing maximal photosystem II fluorescence reappearance following illumination and thermal kinetic windows (TKWs), obtained from the temperature characteristics of enzyme apparent Km values, have been proposed as indicators of the bounds of thermal stress in plants. In this study, we have evaluated the temperature optimum for the accumulation of the chlorophyll a/b light-harvesting complex of photosystem II (LHCP II), its mRNA, and the mRNA of the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) in cucumber (Cucumis sativus L. cv Ashley) as a broader measure of metabolism than that provided by either the fluorescence reappearance or TKWs. The TKW for cucumber is between 23.5 and 39[deg]C, with the minimum apparent Km occurring at 32.5[deg]C. The photosystem II variable fluorescence reappearance following illumination was maximal between 30 and 35[deg]C. Maximum synthesis of the LHCP II occurred at 30[deg] C. The light-induced accumulation of the LHCP II and the small subunit of Rubisco mRNAs showed similar temperature characteristics. Suboptimal temperatures delayed germination, altered cotyledonary soluble sugar content, and broadened the temperature range for chlorophyll accumulation. These results demonstrate an effect of seed reserve mobilization on the range of temperatures for chlorophyll accumulation, and suggest that metabolic temperature characteristics may be broadened by increasing available substrates for enzyme utilization. This study provides new information about the relationship between TKWs and cellular responses to temperature. In addition, the results suggest that the temperature range outside of which plants experience temperature stress is narrower than traditionally supposed.

9.
Plant Physiol ; 107(2): 429-434, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12228369

RESUMEN

We report here an approach to metabolic engineering to alter the temperature characteristics of an enzyme pool based on the concept of thermal kinetics windows (TKWs), a useful indicator of enzyme performance. A chimeric cucumber NADH-hydroxypyruvate reductase (HPR) gene under the control of a cauliflower mosaic virus 35S promoter was constructed and introduced into the genome of tobacco (Tobacum tobacum). The root system of the R1 generation of the resultant transgenic plants expresses only the cucumber enzyme (the native tobacco HPR gene is light regulated and only found in the aerial portions of the plant). Enzyme isolated from the transgenic root tissues exhibits a TKW centered at 32.5[deg]C, characteristic of cucumber. The pool of HPR in the shoots, containing both tobacco and cucumber enzymes, exhibits a broad TKW consistent with an equal mix of the two forms. These data do not simply demonstrate that an introduced gene can be expressed in a transgenic plant but that the kinetics properties of the resultant enzyme are unaltered and when sufficient enzyme is produced the temperature characteristics of the total pool are altered. This suggests that the temperature characteristics of plant biochemical pathways can be broadened to suit changing thermal environments.

10.
Plant Biol (Stuttg) ; 7(3): 315-20, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15912452

RESUMEN

We have employed EST analysis in the resurrection moss Tortula ruralis to discover genes that control vegetative desiccation tolerance and describe the characterization of the EST-derived cDNA TrDr3 ( Tortula ruralis desiccation-stress related). The deduced polypeptide TRDR3 has a predicted molecular mass of 25.5 kDa, predicted pI of 6.7, and six transmembrane helical domains. Preliminary expression analyses demonstrate that the TrDr3 transcript ratio increases in response to slow desiccation relative to the hydrated control in both total and polysomal mRNA (mRNP fraction), which classifies TrDr3 as a rehydrin. Bioinformatic searches of the electronic databases reveal that Tortula TRDR3 shares significant similarities to the hdeD gene product ( HNS- dependent expression) from Escherichia coli. The function of the HdeD protein in E. coli is unknown, but it is postulated to be involved in a mechanism of acid stress defence. To establish the role of E. coli HdeD in abiotic stress tolerance, we determined the log survival percentage from shaking cultures of wild-type bacteria and the isogenic hdeD deletion strain (Delta hdeD) in the presence of low temperature (28 degrees C), elevated NaCl (5 % (w/v)), or decreased pH (4.5), or all treatments simultaneously. The Delta hdeD deletion strain was less sensitive, as compared to wild-type E. coli, in response to decreased pH ( p > 0.009), and the combination of all three stresses ( p > 0.0001).


Asunto(s)
Bryopsida/fisiología , Desecación , Proteínas de Escherichia coli/genética , Proteínas de la Membrana/genética , Proteínas de Plantas/genética , Aclimatación , Secuencia de Aminoácidos , Bryopsida/clasificación , Bryopsida/genética , Frío , ADN/genética , ADN de Plantas/genética , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Peso Molecular , Filogenia , Proteínas de Plantas/química , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transcripción Genética
11.
Med Phys ; 19(5): 1285-91, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1435611

RESUMEN

High-resolution neutron fluence spectra have been measured in the National Accelerator Centre's p(66)/Be(40) neutron therapy beam by the pulsed-beam time-of-flight method. ICRU muscle kerma spectra have been derived from the fluence spectra. Spectral changes resulting from different irradiation conditions have been quantified in terms of the average neutron energy and the fractional low-energy (< 16 MeV) contribution. The changes observed with different thicknesses of polyethylene filtration are consistent with changes in quality parameters determined in biological and microdosimetric experiments. The dosimetry parameters (KtissueA150) N and (Wgas) N calculated for the measured spectra agree with the values recommended in the neutron dosimetry protocol. The shapes of the present fluence spectra differ from previous measurements of p(> 40)/Be spectra. In particular, they differ significantly from the spectrum measured by recoil techniques in an identical neutron therapy unit at the Clatterbridge Hospital, UK. The reasons for the difference are not known.


Asunto(s)
Berilio , Terapia por Captura de Neutrón , Humanos , Matemática , Músculos/efectos de la radiación , Terapia por Captura de Neutrón/métodos , Dosificación Radioterapéutica
12.
Int J Pharm ; 186(1): 31-41, 1999 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-10469921

RESUMEN

Due to the inherent structural instability of proteins, development of chlorofluorocarbon (CFC) free metered dose inhalers (MDIs) containing these biomolecules is beset with numerous challenges. In assessing the conformation of proteins in any medium, both secondary and tertiary structures need to be elucidated. This study uses Fourier transform (FT-) Raman spectroscopy to probe protein conformational stability in hydrofluoroalkane (HFA) propellants. Assignments of molecular modes for lysozyme as a solid and in aqueous solution, and for the first time, HFAs tetrafluoroethane (HFA 134a) and heptafluoropropane (HFA 227) are given. The Raman spectra provided molecular structural information on the peptide backbone, disulfide bonds and C-C stretching vibrations of hen egg lysozyme, enabling the secondary conformation of protein in HFA propellants to be determined; structural integrity of this robust model protein was maintained in both propellants. These results demonstrate that FT-Raman may be a useful tool for the optimisation of protein MDI formulations.


Asunto(s)
Hidrocarburos Fluorados/administración & dosificación , Nebulizadores y Vaporizadores , Conformación Proteica , Estabilidad de Medicamentos , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman
13.
J Pediatr Surg ; 25(12): 1240-1, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2286892

RESUMEN

Many complications are known to occur in association with congenital diaphragmatic hernia. Acute pancreatitis in this situation is very rare. A case is reported and guidelines are given for the management of this complication.


Asunto(s)
Hernias Diafragmáticas Congénitas , Pancreatitis/etiología , Enfermedad Aguda , Preescolar , Hernia Diafragmática/complicaciones , Humanos , Masculino , Vólvulo Gástrico/etiología
14.
Int J Artif Organs ; 25(1): 40-4, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11853070

RESUMEN

Temporary catheters are still essential for acute dialysis access but their performance has not been compared in randomized trials. We conducted a randomized trial of our standard catheter and a newly designed catheter. The primary outcome was maximized blood flow over the entire use of the catheter. Seventy-six patients provided maximum blood flows. The new catheter provided an average blood flow of 349 ml/min and the standard catheter provided flows of 320 ml/mm (p=0.09). Lumen reversal occurred in 56.8% of dialysis sessions with the standard catheter compared to 27.4% with the new catheter (p<0.001). Left-sided internal jugular catheters and catheters inserted in females provided 103 ml/min and 36 ml/min less blood flow, respectively, compared to right sided catheters and catheters placed in males. Approximately 20% of catheters were removed for poor blood flow. Left sided catheters and catheters in females were more likely to need removal for malfunction but catheter design did not influence removal rates.


Asunto(s)
Catéteres de Permanencia , Diálisis Renal/instrumentación , Adolescente , Adulto , Velocidad del Flujo Sanguíneo , Niño , Preescolar , Diseño de Equipo , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Tiempo
15.
Nutr Hosp ; 10(4): 228-33, 1995.
Artículo en Español | MEDLINE | ID: mdl-7662761

RESUMEN

UNLABELLED: The authors present a prospective study whose objective is to estimate the degree of injury from laparoscopic cholecystectomy, by means of the determination of the neuroendocrine response to the surgical aggression. By means of a simple randomization, two study groups are established: group A, consisting of 17 patients subjected to laparoscopic cholecystectomy, and group B, consisting of 18 patients subjected to different techniques of open surgery. EXCLUSION CRITERIA: transfusion of blood derivatives or therapy with corticosteroids. The groups are homogeneous with regard to age, sex, Quetelet index, duration of the intervention, and anaesthetic drugs. A postoperative increase of plasma ACTH, growth hormone, insulin, cortisol and T3 was found in both groups (p < 0.05), and a significant postoperative increase of cortisol and catecholamines in 24 hour urine was found especially in group B. It can be concluded that even though there is an increase of the contraregulatory hormones in the postoperative phase of both groups, the neuroendocrine response is lower after laparoscopic cholecystectomy.


Asunto(s)
Colecistectomía Laparoscópica/efectos adversos , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Análisis de Varianza , Distribución de Chi-Cuadrado , Colecistectomía/efectos adversos , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistemas Neurosecretores/fisiopatología , Complicaciones Posoperatorias/fisiopatología , Estudios Prospectivos
16.
Nutr Hosp ; 9(5): 316-23, 1994.
Artículo en Español | MEDLINE | ID: mdl-7986855

RESUMEN

The use of "all in one" admixtures is supported by an extensive number of studies and by many years of experience. However, we detected stability problems in some mixtures whose stability was previously reported. We made modifications in one of these mixtures [composed of 1.000 ml Freamine 8.5%, 100 ml 10% dextrose, 500 ml water, 500 ml Intralipid 20%, 75 ml electrolyte solution (Na 75 mEq, K 60 mEq, Ca 15 mEg, Mg 15 mEq, Cl 90 mEq, acetate 75 mEq)] in order to see how the different components affect the emulsion stability. All the admixtures were visually inspected after storage during 24 hour at room temperature. It was observed that admixtures with low glucose concentration, high electrolyte levels and high volume were less stable than admixtures containing high glucose, low electrolyte and low volume. Amino acid concentration did not increased the stability as expected. MCT/LCT emulsions were more stable than LCT emulsions. More studies are needed to explain the stability problems of these TPN solutions.


Asunto(s)
Nutrición Parenteral Total/efectos adversos , Aminoácidos/química , Combinación de Medicamentos , Estabilidad de Medicamentos , Electrólitos/química , Estudios de Evaluación como Asunto , Emulsiones Grasas Intravenosas/química , Glucosa/química , Seguridad , Agua/química
17.
Cent Afr J Med ; 38(4): 166-8, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1394398

RESUMEN

Three cases of metastatic Clostridial myonecrosis are reported, two following spontaneous and one following criminal abortion. This particular combination has not been reported before. The two survivors were managed by hysterectomy and disarticulation of the leg through the hip. The patient who died did so before surgery could be undertaken. The literature on gas gangrene infections of the uterus and metastatic Clostridial myonecrosis is reviewed and guidelines for management are discussed.


Asunto(s)
Brazo , Infecciones por Clostridium/diagnóstico , Gangrena Gaseosa/etiología , Pierna , Enfermedades Uterinas/diagnóstico , Aborto Criminal , Aborto Espontáneo , Adulto , Amputación Quirúrgica , Infecciones por Clostridium/complicaciones , Infecciones por Clostridium/cirugía , Femenino , Humanos , Histerectomía , Embarazo , Enfermedades Uterinas/complicaciones , Enfermedades Uterinas/cirugía
18.
Cent Afr J Med ; 35(2): 327-9, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2776198

RESUMEN

Fifty cases of community acquired strains of Staphylococcus aureus causing superficial abscesses were tested for their sensitivity to commonly used antibiotics. Ninety-two percent of isolates were resistant to benzyl-penicillin and ampicillin. Possible causes for this very high level of resistance and the implications for antibiotic usage are discussed.


Asunto(s)
Absceso/microbiología , Resistencia a la Ampicilina , Resistencia a las Penicilinas , Infecciones Cutáneas Estafilocócicas/microbiología , Absceso/tratamiento farmacológico , Ampicilina/uso terapéutico , Humanos , Penicilina G/uso terapéutico , Pautas de la Práctica en Medicina , Infecciones Cutáneas Estafilocócicas/tratamiento farmacológico , Zimbabwe
19.
Acta Otorrinolaringol Esp ; 54(4): 273-6, 2003 Apr.
Artículo en Español | MEDLINE | ID: mdl-12825243

RESUMEN

INTRODUCTION: The success in the surgical management of hyperparathyroidism has conventionally required a bilateral neck exploration. The intraoperative monitoring of intact parathyroid hormone (PTHi), allows a less extensive procedure by confirming the complete removal of hypersecreting tissue. METHODS: Plasma samples were obtained from 32 consecutive patients before and 10 minutes after removal of abnormal parathyroid tissue. PTH was measured with a modifie immunochemiluminometric assay with a short incubation time and the results made available in 15 minutes. RESULTS: PTHi decreased by at least 60% in 30 of 32 cases. A single adenoma was removed in 26 cases, and multiple hyperplastic glands in 4 cases. The two cases in which PTHi fell < 60% were diagnosed as hyperplasia. PTHi decreased > 60% after the removal of the remnant hyperplastic glands. CONCLUSIONS: The rapid PTHi assay had excellent analytical performance and predicted the success of parathyroid surgery.


Asunto(s)
Hiperparatiroidismo/metabolismo , Hiperparatiroidismo/cirugía , Monitoreo Intraoperatorio , Hormona Paratiroidea/metabolismo , Adenoma/metabolismo , Adenoma/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de las Paratiroides/metabolismo , Neoplasias de las Paratiroides/cirugía , Cuidados Preoperatorios , Estudios Prospectivos
20.
Plant Biol (Stuttg) ; 16(5): 935-46, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24397604

RESUMEN

Shoots of bryophytes collected in the desiccated state from the field are likely to be hardened to desiccation tolerance (DT) to varying degrees. To account for this, most studies on DT include a relatively short deacclimation period. However, no study has experimentally determined the appropriate deacclimation time for any bryophyte species. Our purposes are to (i) determine if 'field effects' are biologically relevant to DT studies and how long a deacclimation period is required to remove them; and (ii) utilise field versus cultured shoot responses within the context of a deacclimation period to elucidate the ecological strategy of DT. Our hypothesis (based on an extensive literature on DT) is that a deacclimation period from 24 to 72 h should be sufficient to eliminate historical stress effects on the physiology of the shoots and allow an accurate determination of the inherent ecological DT strategy (constitutive or inducible). We determined, however, using chlorophyll fluorescence and visual estimates of shoot damage, that field-collected shoots of the desert moss Crossidium crassinerve required an experimental deacclimation period of >7 days before field effects were removed, and revealed an ecological DT strategy of inducible DT. If the deacclimation period was <6 days, the shoot response conformed to an ecological strategy of constitutive protection. Thus the presence of field effects can obscure the ecological strategy of desiccation tolerance exhibited by the species, and this translates into a need to re-evaluate previous mechanistic and ecological studies of desiccation tolerance in plants.


Asunto(s)
Bryopsida/fisiología , Estrés Fisiológico , Agua/metabolismo , Aclimatación , Bryopsida/metabolismo , Clorofila/metabolismo , Desecación , Humedad , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Brotes de la Planta/metabolismo , Brotes de la Planta/fisiología
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