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1.
PLoS Biol ; 20(3): e3001576, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35320264

RESUMEN

Mitochondria and the complex endomembrane system are hallmarks of eukaryotic cells. To date, it has been difficult to manipulate organelle structures within single live cells. We developed a FluidFM-based approach to extract, inject, and transplant organelles from and into living cells with subcellular spatial resolution. The technology combines atomic force microscopy, optical microscopy, and nanofluidics to achieve force and volume control with real-time inspection. We developed dedicated probes that allow minimally invasive entry into cells and optimized fluid flow to extract specific organelles. When extracting single or a defined number of mitochondria, their morphology transforms into a pearls-on-a-string phenotype due to locally applied fluidic forces. We show that the induced transition is calcium independent and results in isolated, intact mitochondria. Upon cell-to-cell transplantation, the transferred mitochondria fuse to the host cells mitochondrial network. Transplantation of healthy and drug-impaired mitochondria into primary keratinocytes allowed monitoring of mitochondrial subpopulation rescue. Fusion with the mitochondrial network of recipient cells occurred 20 minutes after transplantation and continued for over 16 hours. After transfer of mitochondria and cell propagation over generations, donor mitochondrial DNA (mtDNA) was replicated in recipient cells without the need for selection pressure. The approach opens new prospects for the study of organelle physiology and homeostasis, but also for therapy, mechanobiology, and synthetic biology.


Asunto(s)
ADN Mitocondrial , Mitocondrias , Calcio , Homeostasis , Mitocondrias/fisiología , Orgánulos
2.
Brain ; 145(5): 1726-1742, 2022 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-35202467

RESUMEN

Neuromyelitis optica is a chronic neuroinflammatory disease, which primarily targets astrocytes and often results in severe axon injury of unknown mechanism. Neuromyelitis optica patients harbour autoantibodies against the astrocytic water channel protein, aquaporin-4 (AQP4-IgG), which induce complement-mediated astrocyte lysis and subsequent axon damage. Using spinal in vivo imaging in a mouse model of such astrocytopathic lesions, we explored the mechanism underlying neuromyelitis optica-related axon injury. Many axons showed a swift and morphologically distinct 'pearls-on-string' transformation also readily detectable in human neuromyelitis optica lesions, which especially affected small calibre axons independently of myelination. Functional imaging revealed that calcium homeostasis was initially preserved in this 'acute axonal beading' state, ruling out disruption of the axonal membrane, which sets this form of axon injury apart from previously described forms of traumatic and inflammatory axon damage. Morphological, pharmacological and genetic analyses showed that AQP4-IgG-induced axon injury involved osmotic stress and ionic overload, but does not appear to use canonical pathways of Wallerian-like degeneration. Subcellular analysis demonstrated remodelling of the axonal cytoskeleton in beaded axons, especially local loss of microtubules. Treatment with the microtubule stabilizer epothilone, a putative therapy approach for traumatic and degenerative axonopathies, prevented axonal beading, while destabilizing microtubules sensitized axons for beading. Our results reveal a distinct form of immune-mediated axon pathology in neuromyelitis optica that mechanistically differs from known cascades of post-traumatic and inflammatory axon loss, and suggest a new strategy for neuroprotection in neuromyelitis optica and related diseases.


Asunto(s)
Neuromielitis Óptica , Animales , Acuaporina 4 , Astrocitos/metabolismo , Autoanticuerpos/metabolismo , Axones/patología , Humanos , Inmunoglobulina G/metabolismo , Ratones , Neuromielitis Óptica/metabolismo
3.
Dermatol Online J ; 29(1)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37040916

RESUMEN

Multicentric reticulohistiocytosis is a rare, non-Langerhans cell histiocytosis that most commonly presents in women in their fourth or fifth decades of life. Cutaneous involvement, characterized by reddish-brown papules in a "string of pearls" or "coral bead" linear formation, and joint involvement are the two most common manifestations at presentation. Histopathology demonstrates dermal proliferation of epithelioid histiocytic-appearing cells with ground glass cytoplasm. We report a 51-year-old woman who presented with ruddy, periungual papules and bilateral joint pain in the hands, consistent with multicentric reticulohistiocytosis. We describe the clinical and histopathologic presentation, therapeutic options, and differential diagnosis of this rare condition.


Asunto(s)
Artritis , Histiocitosis de Células no Langerhans , Enfermedades de la Piel , Humanos , Femenino , Enfermedades de la Piel/patología , Histiocitosis de Células no Langerhans/patología , Diagnóstico Diferencial , Artritis/diagnóstico
4.
Neurochem Res ; 47(9): 2826-2838, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35859078

RESUMEN

Cells in the white matter of the adult brain have a characteristic distribution pattern in which several cells are contiguously connected to each other, making a linear array (LA) resembling pearls-on-a-string parallel to the axon axis. We have been interested in how this pattern of cell distribution changes during aging and remyelination after demyelination. In the present study, with a multiplex staining method, semi-quantitative analysis of the localization of oligodendrocyte lineage cells (oligodendrocyte progenitors, premyelinating oligodendrocytes, and mature oligodendrocytes), astrocytes, and microglia in 8-week-old (young adult) and 32-week-old (aged) corpus callosum showed that young adult cells still include immature oligodendrocytes and that LAs contain a higher proportion of microglia than isolated cells. In aged mice, premyelinating oligodendrocytes were decreased, but microglia continued to be present in the LAs. These results suggest that the presence of microglia is important for the characteristic cell localization pattern of LAs. In a cuprizone-induced demyelination model, we observed re-formation of LAs after completion of cuprizone treatment, concurrent with remyelination. These re-formed LAs again contained more microglia than the isolated cells. This finding supports the hypothesis that microglia contribute to the formation and maintenance of LAs. In addition, regardless of the distribution of cells (LAs or isolated cells), astrocytes were found to be more abundant than in the normal corpus callosum at 24 weeks after cuprizone treatment when remyelination is completed. This suggests that astrocytes are involved in maintaining the functions of remyelinated white matter.


Asunto(s)
Cuprizona , Enfermedades Desmielinizantes , Animales , Cuerpo Calloso , Cuprizona/toxicidad , Enfermedades Desmielinizantes/inducido químicamente , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Vaina de Mielina , Oligodendroglía
5.
J Anat ; 239(1): 32-45, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33641166

RESUMEN

Although the development of the sympathetic trunks was first described >100 years ago, the topographic aspect of their development has received relatively little attention. We visualised the sympathetic trunks in human embryos of 4.5-10 weeks post-fertilisation, using Amira 3D-reconstruction and Cinema 4D-remodelling software. Scattered, intensely staining neural crest-derived ganglionic cells that soon formed longitudinal columns were first seen laterally to the dorsal aorta in the cervical and upper thoracic regions of Carnegie stage (CS)14 embryos. Nerve fibres extending from the communicating branches with the spinal cord reached the trunks at CS15-16 and became incorporated randomly between ganglionic cells. After CS18, ganglionic cells became organised as irregular agglomerates (ganglia) on a craniocaudally continuous cord of nerve fibres, with dorsally more ganglionic cells and ventrally more fibres. Accordingly, the trunks assumed a "pearls-on-a-string" appearance, but size and distribution of the pearls were markedly heterogeneous. The change in position of the sympathetic trunks from lateral (para-aortic) to dorsolateral (prevertebral or paravertebral) is a criterion to distinguish the "primary" and "secondary" sympathetic trunks. We investigated the position of the trunks at vertebral levels T2, T7, L1 and S1. During CS14, the trunks occupied a para-aortic position, which changed into a prevertebral position in the cervical and upper thoracic regions during CS15, and in the lower thoracic and lumbar regions during CS18 and CS20, respectively. The thoracic sympathetic trunks continued to move further dorsally and attained a paravertebral position at CS23. The sacral trunks retained their para-aortic and prevertebral position, and converged into a single column in front of the coccyx. Based on our present and earlier morphometric measurements and literature data, we argue that differential growth accounts for the regional differences in position of the sympathetic trunks.


Asunto(s)
Embrión de Mamíferos/anatomía & histología , Desarrollo Embrionario , Sistema Nervioso Simpático/embriología , Humanos
6.
Radiographics ; 41(2): 609-624, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33577417

RESUMEN

Adnexal torsion is the twisting of the ovary, and often of the fallopian tube, on its ligamental supports, resulting in vascular compromise and ovarian infarction. The definitive management is surgical detorsion, and prompt diagnosis facilitates preservation of the ovary, which is particularly important because this condition predominantly affects premenopausal women. The majority of patients present with severe acute pain, vomiting, and a surgical abdomen, and the diagnosis is often made clinically with corroborative US. However, the symptoms of adnexal torsion can be variable and nonspecific, making an early diagnosis challenging unless this condition is clinically suspected. When adnexal torsion is not clinically suspected, CT or MRI may be performed. Imaging has an important role in identifying adnexal torsion and accelerating definitive treatment, particularly in cases in which the diagnosis is not an early consideration. Several imaging features are characteristic of adnexal torsion and can be seen to varying degrees across different modalities: a massive, edematous ovary migrated to the midline; peripherally displaced ovarian follicles resembling a string of pearls; a benign ovarian lesion acting as a lead mass; surrounding inflammatory change or free fluid; and the uterus pulled toward the side of the affected ovary. Hemorrhage and absence of internal flow or enhancement are suggestive of ovarian infarction. Pertinent conditions to consider in the differential diagnosis are a ruptured hemorrhagic ovarian cyst, massive ovarian edema, ovarian hyperstimulation, and a degenerating leiomyoma. Online supplemental material is available for this article. ©RSNA, 2021.


Asunto(s)
Enfermedades de los Anexos , Quistes Ováricos , Enfermedades de los Anexos/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Torsión Ovárica , Anomalía Torsional/diagnóstico por imagen , Anomalía Torsional/cirugía
7.
Clin Exp Dermatol ; 46(8): 1471-1481, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34047380

RESUMEN

BACKGROUND: Basal cell carcinoma (BCC) is the most common skin cancer in the general population. Treatments vary from Mohs surgery to topical therapy, depending on the subtype. Dermoscopy, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) have gained a foothold in daily clinical practice to optimize diagnosis and subtype-oriented treatment. The new technique of line-field confocal OCT (LC-OCT) allows imaging at high resolution and depth, but its use has not yet been investigated in larger studies. AIM: To evaluate the main LC-OCT criteria for the diagnosis and subtyping of BCC compared with histopathology, OCT and RCM. METHODS: In total, 52 histopathologically confirmed BCCs were evaluated for imaging criteria. Their frequency, predictive values and ROC curves were calculated. A multinominal regression with stepwise variables selection to distinguish BCC subtypes was performed. RESULTS: Nodular BCCs were mainly characterized by atypical keratinocytes, altered dermoepidermal junction (DEJ), tumour nests in the dermis, dark clefting, prominent vascularization and white hyper-reflective stroma. Superficial BCCs showed a thickening of the epidermis due to a series of tumour lobules with clear connection to the DEJ (string of pearls pattern). Infiltrative BCCs were characterized by elongated hyporeflective tumour strands, surrounded by bright collagen (shoal of fish pattern). The overall BCC subtype agreement between LC-OCT and conventional histology was 90.4% (95% CI 79.0-96.8). CONCLUSION: LC-OCT allows noninvasive, real-time identification of BCCs and their subtypes in vertical, horizontal and three-dimension mode compared with histology, RCM and OCT. Further larger studies are needed to better explore the clinical applications of this promising device.


Asunto(s)
Carcinoma Basocelular/diagnóstico por imagen , Carcinoma Basocelular/patología , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/patología , Tomografía de Coherencia Óptica/métodos , Anciano , Carcinoma Basocelular/clasificación , Dermoscopía , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Estudios Prospectivos , Sensibilidad y Especificidad , Neoplasias Cutáneas/clasificación
8.
N Z Vet J ; 69(6): 337-342, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34085907

RESUMEN

AIMS: To compare the mechanical performance and mode of failure in four-point bending of two different 2.0 mm "string of pearls" locking plates that differ in dimensions. METHODS: Ten *2.0 mm, 82 mm long, 10-hole (Plate A) and ten 2.0 mm, 69 mm long, 12-hole (Plate B) Cortical Pearl Systems were secured to plate extenders and centred beneath an Instron tensile tester in four-point bending. In all constructs, a simulated fracture gap was maintained at 33 mm. Due to differences in plate dimensions, 33 mm corresponded to four pearls (Plate A) and six pearls (Plate B). Following an initial preload of 10 N, ramped single-cycle load-to-failure at 0.1 mm/second was performed in five Plate A and five Plate B constructs. Load and displacement were recorded. Constant frequency sinusoidal cyclic loading (33 N) at 20 mm/minute was performed on five Plate A and five Plate B constructs following 10 N of preload. Maximum moment and cycle count were recorded. Testing and data analysis were completed in accordance with the American Society for Testing and Materials F382-14 guidelines. Differences in performance and mode of failure were compared. RESULTS: : Plate A constructs produced higher mean values for bending stiffness (19.8 (SD 2.0) N/mm vs. 10.1 (SD 0.6) N/mm; p < 0.001), bending structural stiffness (0.77 (SD 0.08) Nm2 vs. 0.39 (SD 0.02) Nm2; p < 0.001), yield point (64.1 (SD 4.2) N vs. 54.6 (SD 3.9) N; p = 0.01), proof load (65.4 (SD 3.2) N vs. 55.6 (SD 4.0) N; p = 0.005), and bending strength (1.3 (SD 0.1) Nm vs. 1.1 (SD 0.08) Nm; p = 0.005) when compared to Plate B constructs in single cycle load-to-failure. Plate A constructs had a greater (p = 0.001) mean cycle count to failure (26,178 (SD 4,061) cycles) when compared with Plate B constructs (15,550 (SD 1,291) cycles). All plates failed by non-catastrophic plastic deformation. CONCLUSIONS: Plate A, which is wider, thicker and has a greater spacing between pearls, was mechanically superior to Plate B in four-point bending under single-cycle load-to-failure and sinusoidal cyclic loading. CLINICAL RELEVANCE: Although mechanical differences were identified in four-point bending, in vivo biomechanical performance remains undetermined. By selecting Plate B, the clinician may gain bone purchase through a greater number of pearls and thus screws per unit length, however, the inferior mechanical characteristics, as evaluated in four-point bending, should also be considered. Further research into the mechanical and biomechanical performance of these plating systems is warranted.


Asunto(s)
Fijación Interna de Fracturas , Fracturas Óseas , Animales , Fenómenos Biomecánicos , Placas Óseas/veterinaria , Fijación Interna de Fracturas/veterinaria , Fracturas Óseas/veterinaria
9.
J Dtsch Dermatol Ges ; 19(1): 31-36, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32989899

RESUMEN

Clear cell acanthoma is a rarely diagnosed tumor with variable clinical morphology that is usually only recognized by its histopathological features. The primary lesion is a red papule a few millimeters in diameter that often occurs as a single lesion on the lower extremities. In dermoscopy, resemblance of the vessels to a string of pearls is a largely specific finding of clear cell acanthoma. In contrast to the initially uncharacteristic clinical findings, histopathology of clear cell acanthomas is characterized by a typical compact, well-demarcated acanthosis consisting of pale-staining, PAS-reactive keratinocytes. As etiology and pathogenesis are both unclear, nosology of clear cell acanthoma is also controversial, with an ongoing debate as to its classification as cutaneous neoplasia or reactive inflammatory dermatosis.


Asunto(s)
Acantoma , Queratosis , Neoplasias Cutáneas , Dermoscopía , Humanos , Queratinocitos
10.
Langmuir ; 36(39): 11556-11563, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-32931288

RESUMEN

N-(2-Hydroxypropyl)methacrylamide (HPMA)-based statistical copolymers bearing anticancer drugs have attracted attention for their efficacy in cancer treatments. However, controlling the size and morphology of aggregates of this type of polymer has been challenging and is far from being understood. In this study, small-angle X-ray scattering and asymmetric-flow field-flow fractionation with multiangle light scattering were used to investigate the structure of aggregates formed in aqueous solutions of HPMA-based statistical copolymers of different molecular weights with the model drug pyrene borne in different amounts. The analysis revealed that spherical objects (flower micelles) were formed by the assembly of pyrene moieties in low-molecular-weight copolymers, and the flower micelles connected linearly to form string-of-pearls assemblies (flower necklaces) in high-molecular-weight copolymers. The number of pyrene moieties per polymer chain likely dominates the size and morphology of the copolymer micelles. This study shows how to alter the aggregate structure by changing the molecular weight and composition of copolymers.

11.
Eur J Neurol ; 27(1): 85-91, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31299123

RESUMEN

BACKGROUND AND PURPOSE: The aim of this study was to assess the prevalence of cancer and its characteristics in patients with ischemic stroke and to compare this with cancer prevalence in the general population. METHODS: This was a multicenter cohort study with 2736 patients presenting with ischemic stroke or transient ischemic attack. The prevalence of cancer was assessed by interview and verified by reviewing all medical records. In stroke patients with a history of cancer, we studied the subtype of cancer and its treatment characteristics. We used the national database of The Netherlands Cancer Registry to calculate population-based age and sex cancer standardized prevalence ratios (SPRs) for patients with ischemic stroke. RESULTS: Cancer prevalence in ischemic stroke patients was 12%, corresponding to an SPR of 1.2 [95% confidence interval (CI), 1.0-1.3]. Increased SPRs were observed for cancer of the central nervous system (SPR, 18.2; 95% CI, 9.0-27.4), head and neck (SPR, 3.4; 95% CI, 2.3-4.6), lower respiratory tract (SPR, 2.4; 95% CI, 1.5-3.3) and urinary tract (SPR, 2.1; 95% CI, 1.4-2.9), but not for other cancer types. Cardiovascular risk factors, stroke etiology, treatment and outcome were not different between patients with or without a history of cancer. CONCLUSIONS: In stroke patients, the prevalence of cancer, most prominently cancer of the central nervous system, head and neck, lower respiratory and urinary tract, was higher than in the general population. Medical treatment for the prevention of stroke in cancer survivors deserves further study.


Asunto(s)
Accidente Cerebrovascular Isquémico/epidemiología , Neoplasias/epidemiología , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Comorbilidad , Bases de Datos Factuales , Femenino , Humanos , Ataque Isquémico Transitorio/epidemiología , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Prevalencia , Sistema de Registros , Factores de Riesgo
12.
J Med Primatol ; 49(6): 352-355, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32779224

RESUMEN

This case reports the successful management of a traumatic diaphyseal femoral fracture in an infant Western chimpanzee (Pan troglodytes verus) from a rescue centre in Sierra Leone using a 2.4-mm intramedullary pin and two 2.7-mm String of Pearls™ locking plates. Locking plate use has not been previously described in chimpanzees.


Asunto(s)
Clavos Ortopédicos/veterinaria , Placas Óseas/veterinaria , Fracturas del Fémur/veterinaria , Pan troglodytes/lesiones , Animales , Animales de Zoológico/lesiones , Animales de Zoológico/cirugía , Clavos Ortopédicos/estadística & datos numéricos , Placas Óseas/estadística & datos numéricos , Diáfisis/patología , Femenino , Fracturas del Fémur/cirugía , Pan troglodytes/cirugía , Sierra Leona
13.
J Chem Phys ; 153(6): 064901, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-35287460

RESUMEN

Understanding the conformation of a polyelectrolyte (PE) is not only a fundamental challenge in polymer science but also critical for understanding the folding and aggregation of proteins. Here, we develop a theory by systematically including the electrostatic interactions into the self-consistent field theory for polymers to study the conformational behaviors of a single PE in poor solvents. As the backbone charge fraction of the PE increases, our theory predicts that the spherical globule (Sph) can either be elongated to a series of pearl-necklace (PN) structures or be flattened to two novel structures that have not been reported before: biconcave red cell and toroid. While the PN structures are stable conformations, the two fattened structures are metastable. We find that the cylindrical globule, the stability of which is under debate, is an unstable structure. The signature of the PN structures obtained by our calculation is less pronounced than that reported by other theoretical works due to the continuous change in the curvature from the pearl to the necklace, which, however, is in good agreement with the results from molecular simulations and neutron scattering experiments. In addition, our theory reveals different characteristics of the globule to PN transition: the transition from the Sph to the PN with double pearls is discontinuous, whereas those from adjacent PN structures are continuous at finite salt concentrations. Furthermore, we observe different scaling behaviors: the string width is not a constant as a thermal blob but decays as the backbone charge fraction increases.

14.
Microb Pathog ; 134: 103602, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31226289

RESUMEN

Little attention has been paid to the influence of asymptomatic colonizers of genital tract on female infertility. Albeit, a variety of uropathogens have been known to negatively alter sperm parameters in vitro, but their impact on female fertility outcome under in vivo conditions is not clearly established. Therefore, the present study was intended to investigate the effect of Pseudomonas aeruginosa on sperm parameters and to identify its role in female infertility. The strain of P. aeruginosa was found to reduce sperm motility, viability and sperm Mg++ATPase activity. It could also lead to premature acrosomal loss and induce morphological defect in spermatozoa. For fertility studies, female mice administered intravaginally with 104, 106, 108 cfu of P. aeruginosa for 10 consecutive days, were allowed to mate with proven breeder male on day 12. The results showed that group of mice receiving P. aeruginosa were rendered infertile whereas group receiving PBS showed abdominal distension, string of pearls and finally delivered pups at the end of gestation period. Further, no other clinical manifestation could be observed apparently, histologically or immunologically. Thus, it can be concluded that infertility in mice might be attributed to asymptomatic colonization of genital tract with sperm immobilizing P. aeruginosa.


Asunto(s)
Infertilidad/etiología , Infertilidad/microbiología , Infecciones por Pseudomonas/complicaciones , Pseudomonas aeruginosa/crecimiento & desarrollo , Vagina/microbiología , Acrosoma/metabolismo , Administración Oral , Animales , Antibacterianos/farmacología , ATPasa de Ca(2+) y Mg(2+)/metabolismo , Supervivencia Celular , Citocinas/análisis , Modelos Animales de Enfermedad , Femenino , Humanos , Inmovilización , Infertilidad Masculina/etiología , Inflamación , Masculino , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/patología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/patogenicidad , Reproducción , Aglutinación Espermática , Motilidad Espermática , Espermatozoides/citología , Vagina/patología
16.
BMC Vet Res ; 15(1): 287, 2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31399093

RESUMEN

BACKGROUND: Acetabular fractures comprise 12-30% of canine pelvic fractures and require accurate anatomic reduction and rigid stability to ensure proper healing and minimize future osteoarthritis. Many techniques have been used to repair these fractures, with common techniques including veterinary acetabular plates or use of screw/wire/polymethylmethacrylate constructs. String-of-Pearl™ plating systems have also been used clinically but there is a lack of research supporting their use for these fractures. The purpose of this study was to compare fracture reduction accuracy, biomechanical characteristics, and mode of failure between String-of-Pearls™, veterinary acetabular plates, screw/wire/polymethylmethacrylate constructs in a simulated, ex-vivo acetabular fracture model. We hypothesized that the String-of-Pearls™ constructs would have equivalent or greater mechanical properties and reduction compared to the other constructs. RESULTS: The mean craniocaudal acetabular diameter before fixation (mean 25.2 mm; range 20 mm - 30.1 mm) was not significantly different from after fixation (mean 23.9 mm; range 20 mm - 28.3 mm) for any fixation method. Comparison of reduction scores between groups revealed no significant differences. No significant differences were noted for cyclical displacement or stiffness. There was significant difference with superior failure load of String-of-Pearls™ compared to screw/wire/polymethylmethacrylate in the 75th percentile of animal weight (P = 0.0021), and superior failure load of String-of-Pearls™ compared to veterinary acetabular plates in the 50th (P = 0.0232) and 75th percentiles (P = 0.0058). Stiffness of the String-of-Pearls™ construct was significantly greater than the veterinary acetabular plate construct (P = 0.0417). For ultimate load, String-of-Pearls™ constructs were significantly greater than screw/wire/polymethylmethacrylate (P = 0.0331) and veterinary acetabular plates (P = 0.0218). CONCLUSION: Although the ease of application for the String-of-Pearls™ implant was subjectively better than other implants, no significant differences were found in fracture reduction scores. The String-of-Pearls™ constructs were stiffer than veterinary acetabular plates and exhibited greater failure and ultimate loads compared to veterinary acetabular plates and screw/wire/polymethylmethacrylate fixations. The String-of-Pearls™ implant appears to be a suitable fixation choice for simple canine acetabular fractures.


Asunto(s)
Placas Óseas , Tornillos Óseos , Hilos Ortopédicos , Perros , Fracturas Óseas/cirugía , Polimetil Metacrilato , Animales , Fenómenos Biomecánicos , Cadáver , Femenino , Masculino , Ensayo de Materiales
17.
Pediatr Dermatol ; 36(5): 735-736, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31177579

RESUMEN

Skin lesions in early congenital syphilis can show considerable variability. A 35-day-old infant presented with rhinitis, desquamation of palms and soles, pseudoparalysis of the right upper limb, and annular lesions with peripheral blistering over the chest and abdomen, resembling a "string-of-pearls." A diagnosis of congenital syphilis was made on the basis of radiologic evaluation and reactive Venereal Disease Research Laboratory (VDRL) in both mother and child. We report this case to highlight the unusual presentation of congenital syphilis with annular configuration of blisters, mimicking a "string-of-pearls."


Asunto(s)
Vesícula/patología , Vesícula/virología , Sífilis Congénita/patología , Humanos , Lactante , Masculino
18.
Microsurgery ; 39(6): 548-552, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31225685

RESUMEN

We present our "String of Pearls" technique for upper and lower extremity lymphedema based off the right gastroepiploic artery. The entire laprascopically harvested omentum is placed through a longitudinal incision at the lymphedematous area, and anastomosed proximally, with additional distal venous outflow. This approach preserves the native lymphaticovenous architecture, distributes free lymphatic tissue along the axis of the extremity, and allows for scar release. The additional vein serves to restore bidirectional physiologic drainage inherent in the omentum and providing further lymphaticovenous drainage. We present two cases of upper and lower extremity lymphedema as a result of malignancy treated using this method. The first case was a result of breast cancer in a 55-year-old female with orthotopically placed omentum, and the second case a result of malignant nodular fasciitis in the distal lower extremity in a 56-year-old female with distally placed omentum. No complications occurred. At 3 months follow up, there is a 25% and 28% reduction in lower and upper extremity volume, respectively, with no recurrent cellulitis episodes. The safety and feasibility of placement of the entire omentum longitudinally with additional venous anastomosis are apparent. However, long-term studies are required.


Asunto(s)
Neoplasias de la Mama/cirugía , Arteria Gastroepiploica/cirugía , Ganglios Linfáticos/irrigación sanguínea , Ganglios Linfáticos/trasplante , Linfedema/cirugía , Epiplón/trasplante , Anastomosis Quirúrgica , Brazo/irrigación sanguínea , Femenino , Estudios de Seguimiento , Humanos , Laparoscopía , Pierna/irrigación sanguínea , Persona de Mediana Edad
19.
Vet Surg ; 48(1): 105-111, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30370537

RESUMEN

OBJECTIVE: To describe a surgical technique for rostral mandibulectomy and reconstruction of the mandibular symphysis. STUDY DESIGN: Case report. ANIMAL: One 5-month-old warmblood cross filly. METHODS: A preoperative diagnosis of a juvenile ossifying fibroma was made on the basis of clinical appearance and was later confirmed via histology. The tumor was large, rapidly growing and extending to the caudal aspect of the mandibular symphysis. Computed tomography was performed for surgical planning. The tumor was excised by performing a mandibulectomy caudal to the symphysis. The mandibular symphysis was reconstructed with String of Pearls (SOP) plates. Cortex screws placed in lag fashion, a cortical bone graft from one of the mandibles and a cancellous graft harvested from the tuber coxae. RESULTS: At 9 months of age there was no sign of tumor reoccurrence, the implants were removed because of infection and the mandible had formed a new stable symphysis. The horse was able to prehend food and masticate normally. The owner was pleased with the cosmetic and functional outcome. CONCLUSION: The described surgical technique is a viable option for mandibulectomy and reconstruction of the mandibular symphysis. The technique provided adequate stability for healing to occur in the face of infection. CLINICAL SIGNIFICANCE: Neoplasia and other conditions affecting the entire mandibular symphysis can be treated by complete surgical excision and reconstruction.


Asunto(s)
Autoinjertos/cirugía , Fibroma Osificante/cirugía , Enfermedades de los Caballos/cirugía , Neoplasias Mandibulares/veterinaria , Osteotomía Mandibular/veterinaria , Reconstrucción Mandibular/veterinaria , Animales , Placas Óseas/veterinaria , Hueso Esponjoso/trasplante , Hueso Cortical/trasplante , Femenino , Caballos , Mandíbula/cirugía , Neoplasias Mandibulares/cirugía
20.
Vet Surg ; 48(2): 247-256, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30467870

RESUMEN

OBJECTIVE: To describe and report outcomes after lateral translation of the manus for limb-sparing management of distal radial osteosarcoma in dogs. STUDY DESIGN: Retrospective case series. STUDY POPULATION: Eighteen client-owned dogs. METHODS: The distal aspect of the affected radius and associated neoplastic tissues were excised. The distal aspect of the ulna was preserved except for its medial cortex, which was removed en bloc with the radial segment. The manus was translated laterally to place the radial carpal bone in contact with the distal aspect of the ulna. A limb-sparing or locking compression plate was placed on the remaining proximal radius and the 3rd metacarpal bone. A 3.5-mm SOP (string of pearls) plate was placed on the lateral aspect of the proximal ulna and the 4th metacarpal bone. Dogs were administered chemotherapy. Data were collected to assess surgical and oncologic outcomes. Limb function was subjectively assessed. RESULTS: The percentage of radius removed ranged from 43% to 94% (median 54%). Complications developed in 12 limbs, with infection in 10, biomechanical complications in 6, and local recurrence in 4. Limb function was subjectively assessed as acceptable. Median disease-free interval was 219 days, and median survival time was 370 days. CONCLUSION: Outcomes after lateral translation of the manus compared favorably to other limb-sparing techniques for dogs with distal radial osteosarcoma, particularly in dogs requiring excision of a large segment of the radius. CLINICAL SIGNIFICANCE: The lateral manus translation provides an alternative limb-sparing technique that does not require an allograft, endoprosthesis, or autograft.


Asunto(s)
Neoplasias Óseas/veterinaria , Trasplante Óseo/veterinaria , Enfermedades de los Perros/cirugía , Recuperación del Miembro/veterinaria , Osteosarcoma/veterinaria , Animales , Neoplasias Óseas/cirugía , Perros , Miembro Anterior , Recuperación del Miembro/métodos , Masculino , Recurrencia Local de Neoplasia/veterinaria , Osteosarcoma/cirugía , Prótesis e Implantes , Estudios Retrospectivos , Trasplante Autólogo
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