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1.
Urolithiasis ; 52(1): 21, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38189835

RESUMO

Marine mammals may develop kidney stones, which can be challenging to treat. We describe burst wave lithotripsy (BWL) and ultrasonic propulsion to treat ureteral calculi in a 48-year-old female bottlenose dolphin (Tursiops truncatus) and to reduce renal stone burden in a 23-year-old male harbor seal (Phoca vitulina). BWL and ultrasonic propulsion were delivered transcutaneously in sinusoidal ultrasound bursts to fragment and reposition stones. Targeting and monitoring were performed with real-time imaging integrated within the BWL system. Four dolphin stones were obtained and fragmented ex vivo. The dolphin case received a 10-min and a 20-min BWL treatment conducted approximately 24 h apart to treat two 8-10 mm partially obstructing right mid-ureteral stones, using oral sedation alone. For the harbor seal, while under general anesthesia, retrograde ureteroscopy attempts were unsuccessful because of ureteral tortuosity, and a 30-min BWL treatment was targeted on one 10-mm right kidney stone cluster. All 4 stones fragmented completely to < 2-mm fragments in < 20 min ex vivo. In the dolphin case, the ureteral stones appeared to fragment, spread apart, and move with ultrasonic propulsion. On post-treatment day 1, the ureteral calculi fragments shifted caudally reaching the ureteral orifice on day 9. On day 10, the calculi fragments passed, and the hydroureter resolved. In the harbor seal, the stone cluster was observed to fragment and was not visible on the post-operative computed tomography scan. The seal had gross hematuria and a day of behavior indicating stone passage but overall, an uneventful recovery. BWL and ultrasonic propulsion successfully relieved ureteral stone obstruction in a geriatric dolphin and reduced renal stone burden in a geriatric harbor seal.


Assuntos
Golfinho Nariz-de-Garrafa , Cálculos Renais , Litotripsia , Phoca , Cálculos Ureterais , Animais , Feminino , Masculino , Cálculos Renais/terapia , Cálculos Renais/veterinária , Litotripsia/veterinária , Ultrassom , Cálculos Ureterais/terapia , Cálculos Ureterais/veterinária
2.
Dis Aquat Organ ; 139: 69-79, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32351237

RESUMO

Dolphin tattoo lesions are superficial non-raised skin lesions caused by poxviruses. Their presentation can vary but typical lesions in bottlenose dolphins are circular to ovoid with concentric rings of black stippling. These lesions have at times been suggested as an indicator of overall dolphin health and welfare. This study explored the effect of water temperature on the extent of tattoo lesions in 25 dolphins, along with established hematological health parameters and food consumption. Study animals consisted of 9 males and 16 females with dolphin tattoo lesions ranging in age from 2 to 45 yr. A significant decrease (p < 0.01) in extent and appearance of tattoo lesions was documented following increase in water temperature from 21-24°C (70-75°F) to 25.5-26.5°C (78-80°F). Reduction in tattoo lesions could be noted as early as 2-3 wk following water temperature increase. Marked reduction to complete resolution of tattoo lesions was reproducibly seen 5-6 wk post temperature increase. Food consumption following temperature increase was variable: decrease in intake was noted in 48% of dolphins, increase in intake in 52%. Routine blood parameters (complete blood count, serum chemistry panel, fibrinogen, erythrocyte sedimentation rate) remained within normal limits. A significant increase (p < 0.05) in extent and appearance of tattoo lesions was documented in 3 dolphins as early as 4-5 wk following a decrease in water temperature from 26.1°C (79°F) to 21°C (70°F). Water temperature is a key environmental parameter affecting cetacean pox ('tattoo') lesions in bottlenose dolphins. The absence of changes in hematological parameters along with lack of correlation between extent of pox lesions and food intake indicates that dolphin tattoo lesions are not an appropriate indicator of overall health.


Assuntos
Golfinho Nariz-de-Garrafa , Tatuagem , Animais , Feminino , Masculino , Temperatura , Água
3.
Adv Colloid Interface Sci ; 230: 2-12, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26869216

RESUMO

This review summarizes everything we currently know about the nonionic surfactants alkyl dimethyl (C(n)DMPO) and alkyl diethyl (C(n)DEPO) phosphine oxide (PO surfactants). The review starts with the synthesis and the general properties (Section 2) of these compounds and continues with their interfacial properties (Section 3) such as surface tension, surface rheology, interfacial tension and adsorption at solid surfaces. We discuss studies on thin liquid films and foams stabilized by PO surfactants (Section 4) as well as studies on their self-assembly into lyotropic liquid crystals and microemulsions, respectively (Section 5). We aim at encouraging colleagues from both academia and industry to take on board PO surfactants whenever possible and feasible because of their broad variety of excellent properties.


Assuntos
Óxidos/química , Fosfinas/química , Tensoativos/química , Adsorção , Fosfinas/síntese química , Propriedades de Superfície , Tensoativos/síntese química
4.
Proc Natl Acad Sci U S A ; 112(33): 10371-6, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26240329

RESUMO

It is pointed out that the mystery of how biological systems measure their lengths vanishes away if one premises that they have discovered a way to generate linear waves analogous to compressional sound. These can be used to detect length at either large or small scales using echo timing and fringe counting. It is shown that suitable linear chemical potential waves can, in fact, be manufactured by tuning to criticality conventional reaction-diffusion with a small number substance. Min oscillations in Escherichia coli are cited as precedent resonant length measurement using chemical potential waves analogous to laser detection. Mitotic structures in eukaryotes are identified as candidates for such an effect at higher frequency. The engineering principle is shown to be very general and functionally the same as that used by hearing organs.


Assuntos
Escherichia coli/citologia , Adenosina Trifosfatases/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Engenharia Biomédica , Fenômenos Biofísicos , Proteínas de Ciclo Celular/metabolismo , Proteínas do Citoesqueleto/metabolismo , Difusão , Proteínas de Escherichia coli/metabolismo , Células Gigantes/citologia , Lasers , Modelos Biológicos , Movimento (Física) , Neurônios/citologia , Oscilometria , Espectrometria de Fluorescência , Fuso Acromático
5.
Phys Biol ; 11(5): 053003, 2014 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-25292265

RESUMO

Despite their cultural differences, physics and biology are destined to interact with each other more in the future. The reason is that modern physics is fundamentally about codification of emergent law, and life is the greatest of all emergent phenomena.


Assuntos
Biofísica , Biofísica/métodos , Biofísica/organização & administração
6.
Neuron ; 83(6): 1253-5, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25233307

RESUMO

Experience with complex systems more primitive than the brain teaches important lessons about big data in biology. Chief among them is that physical laws, relationships among measured things that are always true, emerge out of chaos, not the other way around. Correct prediction (as opposed to incorrect prediction) from large data sets requires understanding of these laws. The reason is that the same processes that make them also make the system wildly error-intolerant if the errors are too large. This instability routinely causes computer simulations of even primitive systems to fail by enabling mistakes to cascade into ever worsening falsehoods. The more complex and sophisticated the system is, the more intolerant to errors it becomes.


Assuntos
Encéfalo/fisiologia , Conectoma/métodos , Fenômenos Físicos , Animais , Simulação por Computador , Humanos
7.
Artigo em Inglês | MEDLINE | ID: mdl-23498337

RESUMO

Reconstruction of maxillofacial composite defects is a technically demanding and time-demanding process. It also requires a prolonged treatment course, a team approach, and meticulous planning that is prosthetic and esthetically driven. The use of vascularized flap reconstruction, dental implants, and computer-aided technology and advances in maxillofacial prosthetics has contributed immensely toward the goal of fully reconstructing victims of large avulsive wounds. Further advances in technology, surgical training, and maxillofacial prosthodontics will undoubtedly aid in minimizing the number of surgical interventions and maximize the final functional and esthetic results of these patients.


Assuntos
Ossos Faciais/lesões , Traumatismos Faciais/cirurgia , Traumatismos Maxilofaciais/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Alveoloplastia/métodos , Traumatismos por Explosões/cirurgia , Transplante Ósseo/métodos , Desenho Assistido por Computador , Implantação Dentária Endóssea/métodos , Implantes Dentários , Ossos Faciais/cirurgia , Sobrevivência de Enxerto , Humanos , Prótese Maxilofacial , Planejamento de Assistência ao Paciente , Equipe de Assistência ao Paciente , Complicações Pós-Operatórias , Lesões dos Tecidos Moles/cirurgia , Cirurgia Assistida por Computador/métodos , Retalhos Cirúrgicos/cirurgia , Retalhos Cirúrgicos/transplante , Tomografia Computadorizada por Raios X/métodos , Ferimentos por Arma de Fogo/cirurgia
8.
Langmuir ; 25(20): 12387-92, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19678654

RESUMO

Electrowetting devices often utilize aqueous solutions with ionic surfactants and inorganic salts to modify the electrowetting response. It has been observed in low-voltage electrowetting devices (thin dielectric, <12 V) that a frequent onset of dielectric failure (electrolysis) occurs with use of ionic solutes such as potassium chloride (KCl) or sodium dodecyl sulfate. More detailed current-voltage investigations reveal less dielectric failure for the larger size ions. Specifically, improved resistance to failure is seen for surfactant ions carrying a long alkane chain. Therefore, a catanionic surfactant (in which both ions are amphiphilic) was custom synthesized, and elimination of dielectric failure was observed in both negative and positive voltage. Because water is a small molecule that easily penetrates dielectrics, further experiments were performed to show that dielectric failure can also be eliminated by use of larger size polar molecules such as propylene glycol. In addition to these results, important parameters such as conductivity and interfacial tensions are reported.

9.
J Oral Maxillofac Surg ; 65(1): 89-96, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17174770

RESUMO

PURPOSE: The hypothesis for this prospective evaluation is that resorbable plates are equal to the performance of titanium 2-mm plates, regarding healing of the fracture with bone union and restoration of function. To prove this hypothesis, specific end points will be compared with literature norms for titanium 2-mm miniplate rigid fixation. The primary end point variable for this analysis is the union of the fracture and return to normal function. Secondary end point variables included the incidence of complications such as infection, malunion with malocclusion, soft tissue dehiscence, the need for revision surgery, specific technical challenges, operative time, and the learning curve for the surgeon. PATIENTS AND METHODS: This prospective study consisted of a sequential enrollment of 50 fractures that met the inclusion criteria of having a fracture of the mandibular body, symphysis, angle, or ramus, and required an open reduction and internal fixation for stabilization and repair. The resorbable plates and screws used consisted of an amorphous injection molded copolymer of L-lactide/D-lactide/trimethylene carbonate (Inion CPS system, Tampere, Finland). Data were collated and compared with literature norms for titanium plates and also compared with nonrigid fixation data from a prospective study performed on a similar population in the same institution. RESULTS: Clinical and radiographic evaluation indicated union of all fractures at the eighth follow-up visit. Three sites (6%) noted to have clinical signs of infection were treated immediately upon presentation, with fracture union by 8 weeks. There was no need for revision surgery in this series of patients; 12 screw heads fractured during screw placement and were immediately replaced without significant fracture sequelae. CONCLUSION: Based on this limited series of patients, the hypothesis formulated for this study was validated.


Assuntos
Implantes Absorvíveis , Placas Ósseas , Fixação Interna de Fraturas/instrumentação , Consolidação da Fratura/fisiologia , Fraturas Mandibulares/cirurgia , Adolescente , Adulto , Materiais Biocompatíveis/química , Parafusos Ósseos , Dioxanos/química , Feminino , Seguimentos , Fixação Interna de Fraturas/métodos , Fraturas Mal-Unidas/etiologia , Humanos , Masculino , Má Oclusão/etiologia , Pessoa de Meia-Idade , Poliésteres/química , Estudos Prospectivos , Reoperação , Deiscência da Ferida Operatória/etiologia , Infecção da Ferida Cirúrgica/etiologia , Fatores de Tempo , Titânio/química , Resultado do Tratamento
10.
Phys Rev Lett ; 91(14): 147003, 2003 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-14611548

RESUMO

Recently, a new phenomenological Hamiltonian has been proposed to describe the superconducting cuprates. This so-called Gossamer Hamiltonian is an apt model for a superconductor with strong on-site Coulomb repulsion between the electrons. It is shown that at half-filling the Gossamer superconductor with strong repulsion is unstable toward an antiferromagnetic insulator. The superconducting state undergoes a quantum phase transition to an antiferromagnetic insulator as one increases the on-site Coulomb repulsion. Near the transition the Gossamer superconductor becomes spectroscopically indistinguishable from the insulator.

11.
Crit Care Med ; 31(2): 598-607, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12576972

RESUMO

Severe and prolonged states of catabolic stress have been shown to have profound effects on the intestinal tract microflora and intestinal function. Gut-derived sepsis is a term used to describe a state of systemic inflammation with organ dysfunction after severe catabolic stress hypothesized to be initiated and perpetuated by the intestinal tract microflora. Popular notions of the mechanism of this process have suggested that stress promotes the translocation of intestinal bacteria or their toxins into the systemic compartment resulting in the release of proinflammatory cytokines which participate in the systemic inflammatory response syndrome. This review is an attempt to redefine the mechanism of gut-derived sepsis by focusing on molecular events that result from host-pathogen interactions within the intestinal tract itself. This evidence-based review posits that gut-derived bacteremia, even with potent nosocomial pathogens, is an event of low proinflammatory potential and, itself, is an insufficient stimulus for the systemic inflammatory response and organ failure state typically seen after severe and prolonged catabolic stress. Mechanisms of this apparent paradox are discussed.


Assuntos
Intestinos/microbiologia , Sepse/microbiologia , Bacteriemia/microbiologia , Bactérias/genética , Bactérias/patogenicidade , Translocação Bacteriana , Estado Terminal , Epitélio/microbiologia , Humanos , Pancreatite Necrosante Aguda/microbiologia , Traumatismo por Reperfusão/metabolismo , Virulência
12.
Chem Phys Lipids ; 115(1-2): 63-76, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12047898

RESUMO

Pure all-trans beta-carotene has been prepared on the 10's of grams scale by isothermal Fractional Dissolution (FD) of commercial laboratory samples in tetrahydrofuran (THF). beta-Carotene purified in this way is black, with a faint brownish tinge. The electronic spectra of black samples extend into the near infrared, with end-absorption past 750 nm. Black samples react directly with dioxygen under mild conditions to yield the familiar orange or red powders. Pure beta-carotene rigorously obeys Beer's Law in octane over the entire UV-Vis spectral range, while commercial laboratory samples and recrystallized samples do not. NMR self-diffusion coefficient data demonstrate that beta-carotene exists as simple molecular solutions in octane and toluene. The anomalously high crystallinity of beta-carotene can be attributed (from analysis using molecular mechanics) to the facts that: (1) the number of theoretically possible conformers of beta-carotene is extremely small, and (2) only a small fraction of these (ca. 12%, or 127) may actually exist in fluid phases.


Assuntos
beta Caroteno/síntese química , Cor , Difusão , Espectroscopia de Ressonância Magnética , Octanos/química , Oxigênio/química , Solubilidade , Espectrofotometria Ultravioleta , beta Caroteno/química , beta Caroteno/isolamento & purificação
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