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1.
Oper Dent ; 48(5): E119-E136, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37655625

RESUMEN

OBJECTIVE: This study compares the physical properties and clinical performance of short fiber reinforced composites (SFRC) to those of particulate-filled resin-based composites (PFRC) for class I and II direct restorations in permanent dentition. METHODS: Systematic review and meta-analysis was conducted using PubMed, Embase (Elsevier), and Dentistry and Oral Sciences Source (EBSCO) databases. The outcomes evaluated were physical properties including flexural strength, flexural modulus, elastic modulus, microhardness, shrinkage, fracture toughness, degree of conversion, and depth of cure. Clinical performance was evaluated with a systematic review. RESULTS: The meta-analyses favored SFRC for flexural strength and fracture toughness compared to every PFRC subgroup, with a high quality of evidence. For all other properties, the meta-analyses favored SFRC to overall PFRC, with some non-significant differences with certain PFRC subgroups. The most recent clinical trial showed SFRC performed similarly to PFRC, however older studies suggest inferior surface texture and discoloration of SFRC compared to PFRC. CONCLUSION: This study can aid dental professionals in clinical decision making, supporting that SFRC offers improved physical properties, especially fracture resistance and flexural strength, compared to PFRC.


Asunto(s)
Materiales Dentales , Dentición , Módulo de Elasticidad , Resistencia Flexional
2.
Int J Oral Maxillofac Surg ; 51(10): 1362-1369, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35568657

RESUMEN

The emerging field of global oral and maxillofacial surgery (OMS) aims to improve worldwide access to safe, timely, and affordable OMS care. However, there exists a dearth of literature thoroughly detailing the scope of academic global OMS collaborations between high-income countries (HICs) and low- and/or lower middle-income countries (LICs/LMICs). This scoping review was performed to characterize the landscape of global academic OMS collaborations between HICs and LICs/LMICs. A five-stage methodological framework was used. Academic global OMS collaborations from 1996 to 2020 were identified via an electronic database and grey literature review. A total 1318 articles were identified on December 17, 2020. Following the application of inclusion and exclusion criteria, 71 articles describing 81 unique global OMS academic collaborations were included in the final analysis. The most common HIC was the United States (44.4%); the majority of LIC/LMICs were within Africa (45.8%). Of the total interventions, 89.6% improved LIC/LMIC capacity development, and surgical (43.8%) interventions were the most common. By serving as a central report on current and past academic collaborations in global OMS, this review helps identify areas in need of surgical capacity building, lays the foundation for future research efforts on the topic, and serves as a resource for individuals aiming to become involved in global OMS.


Asunto(s)
Cirugía Bucal , Países en Desarrollo , Humanos , Estados Unidos
3.
Phys Rev Lett ; 123(13): 131801, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31697542

RESUMEN

We report the first measurement of the double-differential and total muon neutrino charged current inclusive cross sections on argon at a mean neutrino energy of 0.8 GeV. Data were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab Booster neutrino beam and correspond to 1.6×10^{20} protons on target of exposure. The measured differential cross sections are presented as a function of muon momentum, using multiple Coulomb scattering as a momentum measurement technique, and the muon angle with respect to the beam direction. We compare the measured cross sections to multiple neutrino event generators and find better agreement with those containing more complete treatment of quasielastic scattering processes at low Q^{2}. The total flux integrated cross section is measured to be 0.693±0.010(stat)±0.165(syst)×10^{-38} cm^{2}.

4.
Biometals ; 31(3): 425-443, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29748743

RESUMEN

Among the properties of lactoferrin (LF) are bactericidal, antianemic, immunomodulatory, antitumour, antiphlogistic effects. Previously we demonstrated its capacity to stabilize in vivo HIF-1-alpha and HIF-2-alpha, which are redox-sensitive multiaimed transcription factors. Various tissues of animals receiving recombinant human LF (rhLF) responded by expressing the HIF-1-alpha target genes, hence such proteins as erythropoietin (EPO), ceruloplasmin, etc. were synthesized in noticeable amounts. Among organs in which EPO synthesis occurred were brain, heart, spleen, liver, kidneys and lungs. Other researchers showed that EPO can act as a protectant against severe brain injury and status epilepticus in rats. Therefore, we tried rhLF as a protector against the severe neurologic disorders developed in rats, such as the rotenone-induced model of Parkinson's disease and experimental autoimmune encephalomyelitis as a model of multiple sclerosis, and observed its capacity to mitigate the grave symptoms. Moreover, an intraperitoneal injection of rhLF into mice 1 h after occlusion of the medial cerebral artery significantly diminished the necrosis area measured on the third day in the ischaemic brain. During this period EPO was synthesized in various murine tissues. It was known that EPO induces nuclear translocation of Nrf2, which, like HIF-1-alpha, is a transcription factor. In view that under conditions of hypoxia both factors demonstrate a synergistic protective effect, we suggested that LF activates the Keap1/Nrf2 signaling pathway, an important link in proliferation and differentiation of normal and malignant cells. J774 macrophages were cultured for 3 days without or in the presence of ferric and ferrous ions (RPMI-1640 and DMEM/F12, respectively). Then cells were incubated with rhLF or Deferiprone. Confocal microscopy revealed nuclear translocation of Nrf2 (the key event in Keap1/Nrf2 signaling) induced by apo-rhLF (iron-free, RPMI-1640). The reference compound Deferiprone (iron chelator) had the similar effect. Upon iron binding (in DMEM/F12) rhLF did not activate the Keap1/Nrf2 pathway. Added to J774, apo-rhLF enhanced transcription of Nrf2-dependent genes coding for glutathione S-transferase P and heme oxygenase-1. Western blotting revealed presence of Nrf2 in mice brain after 6 days of oral administration of apo-rhLF, but not Fe-rhLF or equivalent amount of PBS. Hence, apo-LF, but not holo-LF, induces the translocation of Nrf2 from cytoplasm to the nucleus, probably due to its capacity to induce EPO synthesis.


Asunto(s)
Eritropoyetina/metabolismo , Lactoferrina/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Neuroprotección , Fármacos Neuroprotectores/uso terapéutico , Animales , Isquemia Encefálica/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/inducido químicamente , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Eritropoyetina/administración & dosificación , Femenino , Humanos , Lactoferrina/administración & dosificación , Masculino , Ratones , Ratones Endogámicos BALB C , Esclerosis Múltiple/tratamiento farmacológico , Factor 2 Relacionado con NF-E2/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Ratas , Ratas Wistar , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/metabolismo
5.
Horm Behav ; 100: 12-19, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29481807

RESUMEN

In mice, olfaction is crucial for identifying social odors (pheromones) that signal the presence of suitable mates. We used a custom-built olfactometer and a thirst-motivated olfactory discrimination Go/No-Go (GNG) task to ask whether discrimination of volatile odors is sexually dimorphic and modulated in mice by adult sex hormones. Males and females gonadectomized prior to training failed to learn even the initial phase of the task, which involved nose poking at a port in one location obtaining water at an adjacent port. Gonadally intact males and females readily learned to seek water when male urine (S+) was present but not when female urine (S-) was present; they also learned the task when non-social odorants (amyl acetate, S+; peppermint, S-) were used. When mice were gonadectomized after training the ability of both sexes to discriminate urinary as well as non-social odors was reduced; however, after receiving testosterone propionate (castrated males) or estradiol benzoate (ovariectomized females), task performance was restored to pre-gonadectomy levels. There were no overall sex differences in performance across gonadal conditions in tests with either set of odors; however, ovariectomized females performed more poorly than castrated males in tests with non-social odors. Our results show that circulating sex hormones enable mice of both sexes to learn a GNG task and that gonadectomy reduces, while hormone replacement restores, their ability to discriminate between odors irrespective of the saliency of the odors used. Thus, gonadal hormones were essential for both learning and maintenance of task performance across sex and odor type.


Asunto(s)
Conducta Apetitiva/fisiología , Hormonas Esteroides Gonadales/sangre , Odorantes , Conducta Sexual Animal/fisiología , Olfato/fisiología , Animales , Conducta Apetitiva/efectos de los fármacos , Castración , Estradiol/análogos & derivados , Estradiol/farmacología , Femenino , Hormonas Esteroides Gonadales/metabolismo , Aprendizaje , Masculino , Ratones , Odorantes/análisis , Feromonas/análisis , Condicionamiento Físico Animal/fisiología , Caracteres Sexuales , Conducta Sexual Animal/efectos de los fármacos , Olfato/efectos de los fármacos , Testosterona/farmacología , Orina/química
6.
Eur Phys J C Part Fields ; 78(1): 82, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31258394

RESUMEN

The development and operation of liquid-argon time-projection chambers for neutrino physics has created a need for new approaches to pattern recognition in order to fully exploit the imaging capabilities offered by this technology. Whereas the human brain can excel at identifying features in the recorded events, it is a significant challenge to develop an automated, algorithmic solution. The Pandora Software Development Kit provides functionality to aid the design and implementation of pattern-recognition algorithms. It promotes the use of a multi-algorithm approach to pattern recognition, in which individual algorithms each address a specific task in a particular topology. Many tens of algorithms then carefully build up a picture of the event and, together, provide a robust automated pattern-recognition solution. This paper describes details of the chain of over one hundred Pandora algorithms and tools used to reconstruct cosmic-ray muon and neutrino events in the MicroBooNE detector. Metrics that assess the current pattern-recognition performance are presented for simulated MicroBooNE events, using a selection of final-state event topologies.

7.
Physiol Int ; 103(2): 202-210, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28639858

RESUMEN

It is unknown whether age-related site-specific muscle loss is associated with areal bone mineral density (aBMD) in older adults. To examine the relationships between aBMD and whole-body muscle thickness distribution, 97 healthy adults (46 women and 51 men) aged 50-78 years volunteered. Total and appendicular lean soft tissue mass, aBMD of the lumbar spine (LS-aBMD) and femoral neck (FN-aBMD) were determined using dual-energy X-ray absorptiometry. Muscle thickness (MT) was measured by ultrasound at nine sites of the body (forearm, upper arm, trunk, upper leg, and lower leg). Relationships of each co-variate with aBMD were tested partialling out the effect of age. aBMD was not correlated with either MT of the trunk or anterior lower leg in either sex. In men, significant and relatively strong correlations were observed between anterior and posterior upper arms, posterior lower leg, and anterior upper leg MT and LS-aBMD or FN-aBMD. In women, significant correlations were observed between anterior and posterior upper legs, posterior lower leg, and anterior upper arm MT and FN-aBMD. LS-aBMD was only correlated with forearm and posterior upper leg MT in women. In conclusion, the site-specific association of MT and aBMD differs between sexes and may be associated with the participants' daily physical activity profile.


Asunto(s)
Composición Corporal/fisiología , Densidad Ósea/fisiología , Músculo Esquelético/anatomía & histología , Factores de Edad , Anciano , Brazo , Ejercicio Físico/fisiología , Femenino , Cuello Femoral , Humanos , Pierna , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología
8.
Tsitologiia ; 57(1): 39-46, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-25872374

RESUMEN

Transmission of foreign mtDNA along the paternal lineage founded by male mice (F0), and distribution of that mtDNA in their progeny at early stages of prenatal development were studied. Transmitochondrial males of F0 obtained after injection of human mitochondria into mouse zygotes has been shown to transmit foreign mtDNA to subsequent generations. Individual peculiarities among the males studied, concerning transmission of foreign mtDNA to the progeny, are likely to exist. Besides, the distribution of human mtDNA among blastomeres of transmitochondrial embryos under study differed from that observed in previous investogation of its inheritance along the maternal lineage.


Asunto(s)
ADN Mitocondrial/genética , Embrión de Mamíferos/metabolismo , Patrón de Herencia , Mitocondrias/genética , Cigoto/metabolismo , Animales , Quimera , Femenino , Células Hep G2 , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Mitocondrias/química , Factores Sexuales , Cigoto/crecimiento & desarrollo
9.
Phys Rev Lett ; 113(24): 241803, 2014 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-25541766

RESUMEN

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1 GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged ν(e) charged current cross section on carbon is measured to be ⟨σ⟩(ϕ)=1.11±0.10(stat)±0.18(syst)×10⁻³8 cm²/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10⁻³8 cm²/nucleon and the GENIE prediction is 1.08×10⁻³8 cm²/nucleon. The total ν(e) charged current cross-section result is also in agreement with data from the Gargamelle experiment.

10.
Phys Rev Lett ; 112(18): 181801, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24856687

RESUMEN

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×10(20) protons on target, T2K has fit the energy-dependent νµ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(θ23) is 0.514(-0.056)(+0.055) (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm32(2)=(2.51±0.10)×10(-3) eV(2)/c(4) (inverted hierarchy: Δm13(2)=(2.48±0.10)×10(-3) eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

11.
Phys Rev Lett ; 112(6): 061802, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24580687

RESUMEN

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3) eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

12.
Phys Rev Lett ; 111(21): 211803, 2013 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-24313479

RESUMEN

The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.

13.
Ann Oncol ; 24(3): 710-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23108953

RESUMEN

BACKGROUND: We evaluated AMG 386, an investigational peptibody that neutralizes the interaction between angiopoietins-1 and -2 and the Tie2 receptor, combined with cisplatin/capecitabine (CX) as first-line treatment for metastatic gastro-oesophageal cancer. PATIENTS AND METHODS: Patients with metastatic gastric, gastro-oesophageal junction, or distal oesophageal adenocarcinoma were randomized 1:1:1 to CX (cisplatin 80 mg/m(2) IV Q3W; capecitabine 1000 mg/m(2) P.O. BID for 14 days Q3W) plus intravenous AMG 386 10 mg/kg QW (Arm A) or 3 mg/kg QW (Arm B), or placebo QW (Arm C). The primary end point was estimated progression-free survival (PFS). RESULTS: A total of 171 patients were enrolled. Median estimated PFS in Arms A, B, and C was 4.2, 4.9, and 5.2 months, respectively (hazard ratio for Arms A+B combined versus Arm C, 0.98; 95% CI 0.67-1.43; P = 0.92). Objective response rates were 27% (Arm A), 43% (Arm B), and 35% (Arm C). Incidence of grade ≥3 adverse events was 80% in Arm A, 84% in Arm B, and 75% in Arm C. There was no evidence of pharmacokinetic interactions. CONCLUSIONS: In this study, PFS and ORR were estimated to be similar with AMG 386 plus CX and placebo plus CX treatment. Compared with placebo, toxicity of AMG 386 plus CX was greater but manageable. PREVIOUS PRESENTATION: The results of this study have not been previously published or submitted for publication elsewhere. The results were presented in part at the Gastrointestinal Cancers Symposium, San Francisco, CA, January 20-22, 2011. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov registration number: NCT00583674.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Capecitabina , Enfermedades Cardiovasculares/inducido químicamente , Cisplatino/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Método Doble Ciego , Neoplasias Esofágicas/mortalidad , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/análogos & derivados , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/administración & dosificación , Neoplasias Gástricas/mortalidad , Resultado del Tratamiento , Adulto Joven
14.
Phys Rev Lett ; 107(4): 041801, 2011 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-21866992

RESUMEN

The T2K experiment observes indications of ν(µ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Δm(23)(2)| = 2.4×10(-3) eV(2), sin(2)2θ(23) = 1 and sin(2)2θ(13) = 0, the expected number of such events is 1.5±0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2θ(13) < 0.28(0.34) for δ(CP) = 0 and a normal (inverted) hierarchy.

16.
Vet Comp Orthop Traumatol ; 22(2): 166-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19290401

RESUMEN

This report describes the successful use of the novel fixed-angle locking plating system ALPS (advanced locking plate system) in the case of dorsal tarsometatarsal instability in a cat. Partial arthrodesis of the tarsometatarsal joint was performed with a two hole ALPS 5 and two 2.4 mm selftapping locking screws through a small dorsal approach. Five days after the surgery the cat was walking without lameness. Radiographs made after six weeks showed uneventful healing. ALPS offers an alternative to existing plating systems when selecting an implant for the stabilisation of dorsal tarsometatarsal instabilities in cats.


Asunto(s)
Artrodesis/veterinaria , Gatos/cirugía , Huesos Metatarsianos/cirugía , Huesos Tarsianos/cirugía , Articulaciones Tarsianas/cirugía , Animales , Artrodesis/instrumentación , Artrodesis/métodos , Placas Óseas/veterinaria , Tornillos Óseos/veterinaria , Femenino , Huesos Metatarsianos/anomalías , Huesos Tarsianos/anomalías , Tarso Animal , Resultado del Tratamiento
17.
Vet Comp Orthop Traumatol ; 22(1): 16-20, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19151865

RESUMEN

The influence of the tibial tuberosity conformation on cranial cruciate ligament (CrCl) rupture was evaluated and the size of the tibial tuberosity of healthy dogs (group H) was compared with dogs with CrCl rupture (group R) and dogs treated by tibial tuberosity advancement (TTA) (group T). The medio-lateral radiographs of 219 stifle joints were evaluated. Relative tibial tuberosity width (rTTW), proximal tibial tuberosity angle (PTTA), tibial plateau angle (TPA), tibial width (TW) and tibial plateau length (TPL) were measured on each radiograph. Body weight (BW) was measured and relative body weight (rBW) was calculated. The data from group H was compared with that of group R and group T. Group H had significantly larger rTTW, lower BW, lower rBW and smaller PTTA than group R. A comparison of groups H and T showed that dogs from group H were significantly younger, had a lower BW, a lower rBW, a greater PTTA and a smaller rTTW. In each of the comparisons, the TPA and the TW/TPL were not significantly different. The conformation of the canine tibial tuberosity has a significant influence on CrCl rupture. We hypothesized that the smaller the tibial tuberosity width, the larger the cranial tibial thrust, which results in more rapid CrCL degeneration, thus leading to rupture in a younger population of dogs. The rTTW could be a helpful measurement for breeding selection. Only dogs with a rTTW of more than 0.90 should be used for breeding.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Peso Corporal/fisiología , Perros/lesiones , Rodilla de Cuadrúpedos/diagnóstico por imagen , Tibia/diagnóstico por imagen , Animales , Cruzamiento , Radiografía , Factores de Riesgo , Rotura/veterinaria , Índice de Severidad de la Enfermedad , Rodilla de Cuadrúpedos/patología , Tibia/patología
18.
Tsitologiia ; 50(11): 983-7, 2008.
Artículo en Ruso | MEDLINE | ID: mdl-19140345

RESUMEN

Distribution of human mitochondrial DNA (mtDNA) among separate murine blastomeres was analyzed during the splitting of embryos in which the suspension of human mitochondria had been injected at the one- or two-cell stage. Human mtDNA was detected by PCR with species specific primers. The total amount of the two- and four-cell murine embryos analyzed in the study was 339. In all embryos examined the copies of human mitochondrial genome were revealed along with murine mtDNA, which indicated the phenomenon of an artificially modeled heteroplasmy. The foreign mtDNA was not ubiquitous among the blastomeres of transmitochondrial embryos. Mathematical analysis of the results showed that in the period between the injection of human mitochondria and the subsequent splitting no equal distribution of the human mtDNA occurred in the cytoplasm. These results also point at the presence of more than 2-3 segregation units of mtDNA in the entire pool of mitochondria (about 5 x 10(2)) introduced into an embryo by microinjection.


Asunto(s)
Blastómeros/metabolismo , ADN Mitocondrial/metabolismo , Embrión de Mamíferos/metabolismo , Animales , Blastómeros/química , ADN Mitocondrial/análisis , ADN Mitocondrial/genética , Frecuencia de los Genes , Humanos , Ratones , Ratones Transgénicos , Mitocondrias Hepáticas/química
19.
J Chem Phys ; 123(9): 94301, 2005 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16164339

RESUMEN

The hydrogen or deuterium atom abstraction reactions between Cl((2)P(3/2)) and methane, or its deuterated analogues CD(4) and CH(2)D(2), have been studied at mean collision energies around 0.34 eV. The experiments were performed in a coexpansion of molecular chlorine and methane in helium, with the atomic Cl reactants generated by polarized laser photodissociation of Cl(2) at 308 nm. The Cl-atom reactants and the methyl radical products were detected using (2+1) resonantly enhanced multiphoton ionization, coupled with velocity-map ion imaging. Analysis of the ion images reveals that in single-beam experiments of this type, careful consideration must be given to the spread of reagent velocities and collision energies. Using the reactions of Cl with CH(4), CD(4), and CH(2)D(2), as examples, it is shown that the data can be fitted well if the reagent motion is correctly described, and the angular scattering distributions can be obtained with confidence. New evidence is also provided that the CD(3) radicals from the Cl+CD(4) reaction possess significant rotational alignment under the conditions of the present study. The results are compared with previous experimental and theoretical works, where these are available.

20.
J Small Anim Pract ; 46(5): 227-31, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15909445

RESUMEN

OBJECTIVES: To evaluate indications for and outcome of perineal urethrostomy in cats. METHODS: The medical records of 59 cats that had undergone perineal urethrostomy were evaluated. Short-term follow up information (for a period of four weeks following surgery) was available for all of the cats. Long-term follow up information (for a period of at least four months) was available for 39 cats. RESULTS: Early complications occurred in 25.4 per cent of cats and late complications were observed in 28.2 per cent of cats. The most frequent late complication was recurring bacterial urinary tract Infection. CLINICAL SIGNIFICANCE: Despite frequent complications and recurring signs of lower urinary tract disease, 32.2 per cent of the cats had a disease-free long-term outcome (mean four years, median 3.9 years), and 88.6 per cent of clients interviewed thought that their cats had a good quality of life after surgery.


Asunto(s)
Enfermedades de los Gatos/cirugía , Uretra/cirugía , Enfermedades Uretrales/veterinaria , Derivación Urinaria/veterinaria , Animales , Gatos , Masculino , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/veterinaria , Calidad de Vida , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento , Enfermedades Uretrales/cirugía , Derivación Urinaria/métodos , Infecciones Urinarias/epidemiología , Infecciones Urinarias/etiología , Infecciones Urinarias/veterinaria
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