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1.
Curr Osteoporos Rep ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39254815

RESUMEN

PURPOSE OF REVIEW: We review the literature about patients 50 years and older with a recent clinical fracture for the presence of skeletal and extra-skeletal risks, their perspectives of imminent subsequent fracture, falls, mortality, and other risks, and on the role of the fracture liaison service (FLS) for timely secondary fracture prevention. RECENT FINDINGS: Patients with a recent clinical fracture present with heterogeneous patterns of bone-, fall-, and comorbidity-related risks. Short-term perspectives include bone loss, increased risk of fractures, falls, and mortality, and a decrease in physical performance and quality of life. Combined evaluation of bone, fall risk, and the presence of associated comorbidities contributes to treatment strategies. Since fractures are related to interactions of bone-, fall-, and comorbidity-related risks, there is no one-single-discipline-fits-all approach but a need for a multidisciplinary approach at the FLS to consider all phenotypes for evaluation and treatment in an individual patient.

2.
Osteoporos Int ; 31(3): 567-576, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31784787

RESUMEN

Manual correction of automatically generated contours for high-resolution peripheral quantitative computed tomography can be time consuming and introduces precision error. However, bias related to the automated protocol is unknown. This study provides insight into error bias that is present when using uncorrected contours and inter-operator precision error based on operator training. INTRODUCTION: High-resolution peripheral quantitative computed tomography workflow includes manually correcting contours generated by the manufacturer's automated protocol. There is interest in minimizing corrections to save time and reduce precision error; however, bias related to the automated protocol is unknown. This study quantifies error bias when contours are uncorrected and identifies the impact of operator training on bias and precision error. METHODS: Forty-five radii and tibiae scans across a representative range of bone density were analyzed using the automated and manually corrected contours of three operators, with training ranging from beginner to expert, and compared with a "ground truth" to estimate bias. Inter-operator precision was measured across operators. RESULTS: The tibia had greater error bias than the radius when contours were uncorrected, with compartmental bone mineral densities and cortical microarchitecture having greatest biases, which could have significant implications for interpretation of studies using this skeletal site. Bias and precision error were greatest when contours were corrected by the beginner operator; however, when this operator was removed, bias was no longer present and inter-operator precision was between 0.01 and 3.74% for all parameters except cortical porosity. CONCLUSION: These findings establish the need for manual correction and provide guidance on operator training needed to maximize workflow efficiency.


Asunto(s)
Huesos , Radio (Anatomía) , Sesgo , Densidad Ósea , Humanos , Radio (Anatomía)/diagnóstico por imagen , Reproducibilidad de los Resultados , Tibia/diagnóstico por imagen , Flujo de Trabajo
3.
Osteoporos Int ; 31(9): 1607-1627, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32458029

RESUMEN

INTRODUCTION: The application of high-resolution peripheral quantitative computed tomography (HR-pQCT) to assess bone microarchitecture has grown rapidly since its introduction in 2005. As the use of HR-pQCT for clinical research continues to grow, there is an urgent need to form a consensus on imaging and analysis methodologies so that studies can be appropriately compared. In addition, with the recent introduction of the second-generation HrpQCT, which differs from the first-generation HR-pQCT in scan region, resolution, and morphological measurement techniques, there is a need for guidelines on appropriate reporting of results and considerations as the field adopts newer systems. METHODS: A joint working group between the International Osteoporosis Foundation, American Society of Bone and Mineral Research, and European Calcified Tissue Society convened in person and by teleconference over several years to produce the guidelines and recommendations presented in this document. RESULTS: An overview and discussion is provided for (1) standardized protocol for imaging distal radius and tibia sites using HR-pQCT, with the importance of quality control and operator training discussed; (2) standardized terminology and recommendations on reporting results; (3) factors influencing accuracy and precision error, with considerations for longitudinal and multi-center study designs; and finally (4) comparison between scanner generations and other high-resolution CT systems. CONCLUSION: This article addresses the need for standardization of HR-pQCT imaging techniques and terminology, provides guidance on interpretation and reporting of results, and discusses unresolved issues in the field.


Asunto(s)
Densidad Ósea , Osteoporosis , Humanos , Osteoporosis/diagnóstico por imagen , Radio (Anatomía)/diagnóstico por imagen , Tibia , Tomografía Computarizada por Rayos X
4.
Theriogenology ; 66(2): 166-72, 2006 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-16310840

RESUMEN

Two experiments were conducted to investigate the effects of timing of prostaglandin F2(alpha) (PGF2(alpha)) administration, controlled internal drug release device (CIDR) removal and second gonodotropin releasing hormone (GnRH) administration on the pregnancy outcome in CIDR-based synchronization protocols. In Experiment 1, suckled Angus crossbred beef cows (n = 580) were given 100 microg of GnRH+a CIDR on Day 0. Cows in Group 1 (modified Ovsynch-P) received 25 mg of dinoprost (PGF2(alpha)) and CIDR device removal on Day 8 (AM), 100 microg of GnRH 36 h later on Day 9 (p.m.), and fixed-time AI (FTAI) 16 h later on Day 10 (47.5+/-1.1 h after PGF2(alpha)). Cows in Group 2 (Ovsynch-P) received 25mg of PGF2(alpha) and CIDR device removal on Day 7 (p.m.), 100 microg of GnRH 48 h later on Day 9 and FTAI 16 h later on Day 10 (66.6+/-1.2 h after PGF2(alpha)). Pregnancy rates were 56.5% (170/301) for Group 1 and 55.6% (155/279) for Group 2, respectively (P = 0.47). In Experiment 2, beef cows (n=734) were synchronized with 100 microg of GnRH+CIDR on Day 0, 25 mg of PGF2(alpha) and CIDR device removal on Day 7 and either 100 microg of GnRH 48 h later on Day 9 (Ovsynch-P) and FTAI 16 h later on Day 10 (64.9+/-3.3 h from PGF2(alpha)) or 100 microg of GnRH on Day 10 (CO-Synch-P) at the time of AI (63.2+/-4.2 h from PGF2(alpha)). Pregnancy rates were 48.8% (180/369) for Ovsynch-P and 44.7% (163/365) for CO-synch-P groups, respectively (P = 0.11). In both experiments, there was a locationxtreatment interaction (P<0.05); pregnancy rates between locations were different (P < 0.05) in the Ovsynch-P group. In conclusion, in a CIDR-based Ovsynch synchronization protocol, delaying administration of prostaglandin and CIDR removal by 12 h, or timing of the second GnRH by 16 h, did not affect pregnancy rates to FTAI. Therefore, there may be an opportunity to make changes in synchronization protocols with out adversely affecting FTAI pregnancy rates.


Asunto(s)
Bovinos/fisiología , Dinoprost/administración & dosificación , Fármacos para la Fertilidad Femenina/administración & dosificación , Hormona Liberadora de Gonadotropina/administración & dosificación , Inseminación Artificial/veterinaria , Índice de Embarazo , Animales , Sistemas de Liberación de Medicamentos/instrumentación , Sistemas de Liberación de Medicamentos/veterinaria , Implantes de Medicamentos , Sincronización del Estro , Femenino , Gonadotropinas/metabolismo , Lactancia , Embarazo , Distribución Aleatoria , Factores de Tiempo
5.
Science ; 252(5003): 321-2, 1991 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-17769280
6.
Meat Sci ; 57(4): 359-63, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22061707

RESUMEN

We investigated whether consumer preferences for beef colors (red, purple, and brown) or for beef packaging systems (modified atmosphere, MAP; vacuum skin pack, VSP; or overwrap with polyvinyl chloride, PVC) influenced taste scores of beef steaks and patties. To test beef color effects, boneless beef top loin steaks (choice) and ground beef patties (20% fat) were packaged in different atmospheres to promote development of red, purple, and brown color. To test effects of package type, steaks and patties were pre-treated with carbon monoxide in MAP to promote development of red color, and some meat was repackaged using VSP or PVC overwrap. The differently colored and packaged meats were separately displayed for members of four consumer panels who evaluated appearance and indicated their likelihood to purchase similar meat. Next, the panelists tasted meat samples from what they had been told were the packaging treatments just observed. However, the meat samples actually served were from a single untreated steak or patty. Thus, any difference in taste scores should reflect expectations established during the visual evaluation. The same ballot and sample coding were used for both the visual and taste evaluations. Color and packaging influenced (P<0.001) appearance scores and likelihood to purchase. Appearance scores were rated red>purple >brown and PVC >VSP>MAP. Appearance scores and likelihood to purchase were correlated (r=0.9). However, color or packaging did not affect (P>0.5) taste scores. Thus, consumer preferences for beef color and packaging influenced likelihood to purchase, but did not bias eating satisfaction.

7.
Meat Sci ; 59(3): 317-24, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22062786

RESUMEN

Our goal was to obtain > 21 days red color stability for carbon monoxide (CO)-treated beef steaks in vacuum packaging (VP). In preliminary tests, pretreatment for 24 h in a 5% CO modified atmosphere package (MAP) was needed to maintain redness after re-packaging in VP. Pressure pretreatment with 5% CO for 2 h developed redness, but was impractical for large-scale application. Color stability and microbial load were then compared after treatment of steaks in 5% CO-MAP for 24 h, then VP; 100% CO-MAP for 1 h, then VP; steaks and ground beef in 0.5% CO-MAP; and steaks and ground beef in polyvinyl chloride (PVC) wrap. Steaks remained red for 5, 6, 8 and <1-week storage at 2°C, respectively. Steaks microbial load exceeded spoilage levels (>10(6)cfu/cm(2)) at 5, 6, 7 and <2-weeks, respectively. Thus, extended color stability in VP was achieved by pretreatment with 5% CO for 24 h or 100% CO for 1 h.

8.
J Zoo Wildl Med ; 28(4): 464-70, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9523641

RESUMEN

Reference hematologic and plasma biochemical values from island (Pteropus hypomelanus), Malaysian (P. vampyrus), and Rodriquez Island (P. rodricensis) flying foxes were determined. In comparison to other mammals, these bats had very low plasma cholesterol and urea levels, which may be related to diet. The predominant white blood cells observed in P. hypomelanus and P. vampyrus were lymphocytes, while in P. rodricensis they were neutrophils. Elevated plasma levels of calcium, phosphorus, and alkaline phosphatase observed in the juvenile P. hypomelanus were expected, given the greater osteogenic activity of growing animals. In P. hypomelanus, bilirubin levels were higher in juveniles than in adults, and cholesterol levels were higher in females than in males.


Asunto(s)
Quirópteros/sangre , Factores de Edad , Animales , Análisis Químico de la Sangre/veterinaria , Glucemia/análisis , Recolección de Muestras de Sangre/veterinaria , Femenino , Florida , Hematócrito/veterinaria , Pruebas Hematológicas/veterinaria , Hemoglobinas/análisis , Masculino , Embarazo , Valores de Referencia , Manejo de Especímenes/veterinaria
9.
J Food Sci ; 72(7): C351-5, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17995631

RESUMEN

The USDA FSIS meat and poultry jerky compliance guidelines recommend a high humidity or liquid immersion pasteurization step before drying. The objective of this study was to evaluate the effects of high humidity (>90%) or wet marinade pasteurization on jerky characteristics (water activity, moisture/protein ratio, total aerobic plate count [TAC]) and sensory properties. Jerky pasteurized by nonmarinade method A (76.6 degrees C dry bulb, 54.4 degrees C oven wet bulb temperature for 1 h) had highest sensory scores for spice intensity and interior cured color (redness), and generally lower TACs than jerky from marinade pasteurization methods. Jerky pasteurized by method B (54 degrees C for 121 min in marinade) had higher TACs than other methods. Approximately 2-log reduction in TAC was observed using marinade pasteurization in the smokehouse to internal temperature of 60 degrees for 12 min (method C), or in hot marinade to internal temperature of 70 degrees C before drying (method D), but jerky was less spicy and somewhat darker than jerky from method A. Extruded jerky (1.5-cm thickness) was similar to intact jerky for spice flavor intensity and interior redness, but required longer drying time to reach the target Aw of 0.85. Marinade pasteurization by methods C or D was feasible, and may be a preferred alternative for some processors, since monitoring of oven humidity during pasteurization is not necessary.


Asunto(s)
Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Calor , Productos de la Carne/normas , Productos Avícolas/normas , Animales , Bovinos , Recuento de Colonia Microbiana , Comportamiento del Consumidor , Desecación , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Humanos , Humedad , Productos de la Carne/microbiología , Productos Avícolas/microbiología , Proteínas/análisis , Gusto , Factores de Tiempo , Agua/metabolismo
10.
Planta ; 111(1): 85-90, 1973 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24469421

RESUMEN

The level of induced apogamy in gametophytic colonies of Pteridium aquilinum (L.) Kuhn is altered by varying the number of colonies per culture vessel or by including a constant number of colonies in culture vessels of different volumes. In either case, placing vials of mercuric perchlorate, an absorber of ethylene, within the closed culture vessels reduced the apogamous response to a very low level. Production of ethylene by the gametophytes was demonstrated by gas chromatography. Ethylene supplied in a continuous-flow system promoted the apogamous response above that of an air control.

11.
Am J Bot ; 87(7): 920-4, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10898769

RESUMEN

Mature, gametangia-bearing photosynthetic gametophytes of Phylloglossum can be grown from the nonphotosynthetic, cylindrical, negatively gravitropic immature stages in illuminated axenic culture on a nutrient medium with or without 0.2% glucose. The gametangial-bearing region of these gametophytes, the photosynthetic crown, grows horizontally from the apex of the immature cylindrical stage. At maturity the photosynthetic crown is thickened and bilaterally symmetrical. It is usually narrow and bean-shaped with dorsal and ventral regions. Occasionally, the ventral region becomes thicker and the crown is deltoid in cross section. The dorsal edge or ridge of the crown is the gametangial region with archegonia and antheridia. The gametangia are often hidden because they are interspersed among numerous uni- or bicellular paraphyses. The lateral surfaces below the gametangial region lack outgrowths, and the ventral region is covered with long rhizoids. The apical meristem at the anterior end of the crown is overarched by the developing dorsal tissue of the gametangial ridge. The lower derivatives of the meristem form the ventral region with rhizoids. Phylloglossum gametophytes are unusual because their mode of organic nutrition changes from mycorrhizal to photosynthetic during ontogeny.

12.
Planta ; 99(2): 174-8, 1971 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24487554

RESUMEN

Pteridium gametophytes cultured on a medium containing 4% sucrose under various qualities of light exhibit different developmental responses. Under far-red illumination (690-730 nm) apogamy is produced without enhanced gametophytic growth, thus allowing a distinct separation of the specific induction of apogamy from a general enhancement of gametophytic growth.

13.
Am Ind Hyg Assoc J ; 40(2): 108-17, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-495442

RESUMEN

The results of an industry-wide study to determine the exposure of workers to man-made mineral fibers are summarized. The purpose of the study was to determine current employee exposures to airborne fibers and to utilize results to estimate past exposures. Measured exposures of workers to airborne total particulate matter and fibers are presented; samples were evaluated by phase contrast and electron microscopy. Results of the three year study, which encompassed 16 facilities and over 1500 eight hour samples, show that although there is a wide variation in concentrations of airborne fibers and particulate matter between and within the facilities surveyed, the concentrations of airborne particulate matter and fibers are generally less than 2.5 mg/m3 and 0.5 fibers/cm3, respectively. The norminal fiber size of the fibers manufactured and average airborne fiber concentration were highly correlated.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Contaminantes Atmosféricos/análisis , Polvo/análisis , Vidrio , Industria Textil , Exposición a Riesgos Ambientales , Humanos , Métodos , Textiles
14.
Am J Bot ; 88(7): 1151-63, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11454615

RESUMEN

In this correlated SEM (scanning electron microscope) and TEM (transmission electron microscope) investigation, we describe architectural details of the multiflagellated sperm cell of Psilotum nudum. Comparisons with other pteridophytes are made to (1) assess the placement of Psilotum among pteridophyte taxa and (2) evaluate structural modifications of sperm cells during land plant evolution. The released spermatozoid of Psilotum coils 2.0 revolutions and is outlined by a parallel band of up to 190 microtubules. The elongated nucleus is highly compacted and parallels the cellular coils with numerous mitochondria and starch-laden plastids distributed along its length. Along the anterior coil is an elaborate locomotory apparatus that includes ∼36 flagella that are inserted into the cell by basal bodies. Subtending the basal bodies is the multilayered structure, which consists of a long narrow lamellar strip and an overlying band of microtubules. An elongated anterior mitochondrion underlies the multilayered structure. Additional amyloplasts and mitochondria are aggregated along the anterior coil in association with the locomotory apparatus, while a fibrous band encircles the leading edge of the cell. Salient features of this cell, including details of the locomotory apparatus, structure and position of organelles, and arrangement of the spline, are shared by spermatozoids of Equisetum and ferns (including eusporangiate and leptosporangiate taxa). Thus, this study provides morphological support for the hypothesis that Psilotum nudum is a member of an assemblage that includes ferns and Equisetum. However, the less streamlined architecture of Psilotum gametes and the lack of architectural features shared with any specific taxon examined to date suggest that Psilotum is an early divergent fern, with relatively remote affinities to Ophioglossaceae and Equisetaceae.

16.
J Air Pollut Control Assoc ; 22(5): 359-63, 1972 May.
Artículo en Inglés | MEDLINE | ID: mdl-5041617

Asunto(s)
Sulfuros , Metano , Fotólisis
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