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1.
J Hand Surg Glob Online ; 5(4): 498-502, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37521562

RESUMO

Purpose: The lacertus fibrosus or bicipital aponeurosis is a sheet of ligamentous tissue just distal to the elbow joint and can be a compression point for the median nerve. Essentially, lacertus syndrome is a subset of pronator syndrome and an uncommon diagnosis by itself. Surgical release of the lacertus consists of a small 2-cm incision that can be performed under local anesthesia. This study aimed to evaluate the outcome of lacertus release in resolving median nerve symptoms. Methods: This retrospective study was performed at Prince Court Medical Centre, Kuala Lumpur, Malaysia, from January 2020 until June 2021. Ninety-three patients who presented with numbness of fingers, hand, or upper limb; forearm pain; and muscle weakness. They were diagnosed with lacertus syndrome on the basis of local tenderness at the lacertus fibrosus with either weakness of flexor pollicis longus and flexor digitorum profundus of the index finger or paresthesia over the thenar eminence. The patients underwent 3 months of hand therapy, and those with no symptom improvement were offered lacertus release performed by a single surgeon. The surgical technique consists of a surgical incision starting from a point 2 cm distally and 2 cm radially to the medial epicondyle. The incision projects 2 cm distally in an oblique fashion toward the radial styloid. A wide-awake local anesthesia no tourniquet (WALANT) technqiue was utilized and 20 mL of local anesthesic was injected subcutaneously around this region at least 20 minutes before the surgery. Careful dissection was made subcutaneously, and the lacertus fibrosus was identified as a thickened, shiny white structure and released. The Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, grip strength, and pinch strength were tested before and after surgery. At 6 months after surgery, the QuickDASH score was again assessed with a WALANT satisfactory questionnaire. Results: A total of 93 patients were included in the study. The mean age of the patients was 38.7 years, and most were women (77.4%). The mean operating time was 70 minutes. The mean preoperative QuickDASH score was 53, which significantly reduced immediately after surgery to 7.8 (P < .001) and remained low at 6 months after surgery (10.6). The mean grip strength showed a significant increase from a preoperative mean of 16 kg to a postoperative mean of 24 kg (P < .001). Pinch strength also significantly increased from a preoperative mean of 9 kg to 13 kg after surgery (P < .001). Conclusions: Lacertus syndrome remains an underdiagnosed disease that can be treated efficiently with a directed minimal surgical incision under wide-awake local anesthesia. Lacertus release appears to significantly reduce pain and numbness with markedly improved hand grip and pinch strength. The corresponding QuickDASH scores also improved significantly after surgery. This study is vital to our understanding of proximal median nerve entrapment and to accurately diagnose it. Type of study/level of evidence: Therapeutic III.

2.
Cureus ; 13(7): e16269, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34377605

RESUMO

Background The Wide-Awake-Local-Anaesthesia-No-Tourniquet (WALANT) technique achieves an almost bloodless field for clear visualization during surgeries. WALANT utilizes lidocaine and epinephrine for anesthesia and hemostasis, respectively, without the usage of sedation and tourniquet. This avoids the potential side effects of tourniquet-related pain and sedation-related complications. However, acceptance is still low due to concerns regarding the safety of epinephrine injection in the finger. There is a persistent belief that epinephrine can cause digital ischemia. Purpose To evaluate retrospectively possible complications of hand surgeries performed using the WALANT technique. Methods All finger and hand procedures performed under the WALANT technique from June 2016 to May 2021 in an urban tertiary hospital were studied retrospectively. Results There were a total of 1073 cases, of which 694 were females and 379 were males. The mean age was 55 years. Finger surgeries (e.g., trigger finger release, excision of finger lesions, removal of implants) consisted of 707 cases; and the rest (366 cases) were hand surgeries (e.g., carpal tunnel release, excision of hand lesions, removal of implants). In all cases reviewed, there were no instances of circulatory compromise. There were also no circumstances where usage of reversal with phentolamine is recorded. Conclusion We believe that performing finger and hand surgeries using the WALANT technique is safe and beneficial. The usage of WALANT in hand surgeries avoids tourniquet pain. However, WALANT should be used with caution in those with vascular insufficiency or disease.

3.
Surg Endosc ; 32(12): 4813-4819, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29766307

RESUMO

BACKGROUND: Paediatric laparoscopic procedures are now becoming routine practice. Therefore, there is a need for simulated laparoscopic models to acquire part-procedural competency prior to direct patient contact in a safe learning environment. For this reason, we chose two paediatric conditions; inguinal hernia (IH) and congenital diaphragmatic hernia (CDH), which were combined to create the laparoscopic inguinal and diaphragmatic defect (LIDD) model. Our aim was to assess this novel surgical simulation model by determining its construct and content validity. METHODS: A total of 107 participants completed the validation study: volunteer medical students (novices), surgical trainees (intermediate) and consultant surgeons (experts). Basic demographic data were collected. Subjects were shown a pre-recorded video of both exercises. The assessment exercise involved closing both the simulated inguinal or diaphragmatic hernial orifice. The task was assessed using a novel scoring system with a maximum score of 21 for IH model and 15 for the CDH. The content validity was assessed by a 6-point Likert scale of the expert group. RESULTS: 105/107 participants successfully completed the two exercises. Both aspects of the LIDD model revealed a statistical significance between the scores obtained by the three groups of subjects. Experts scored 20.3/21 for the IH and 14.8/15 for the CDH models which significantly higher than medical students (6.3/21 and 5.3/15; p < 0.05 for both) and trainees (11.2/21 and 9.3/15; p < 0.05 for both). Similarly, trainees performed significantly better than medical students in both models (p < 0.05). Therefore, the LIDD model was found to have a good construct validity. It was, however, unable to differentiate between the various levels of trainees in the intermediate group. Content validity from the experts revealed that there was a high score for the potential of both aspects of LIDD (4.8 and 4.8). There was also a high level of functional fidelity for task completion (4.0 and 4.0). CONCLUSIONS: We have demonstrated both the construct and content validity of the LIDD model for both laparoscopic IH and CDH repair. It was able to successfully differentiate between the expert, trainees and inexperienced laparoscopic surgeons.


Assuntos
Hérnia Inguinal/cirurgia , Hérnias Diafragmáticas Congênitas/cirurgia , Laparoscopia/educação , Treinamento por Simulação/métodos , Adulto , Competência Clínica , Feminino , Humanos , Masculino
4.
Nat Commun ; 8: 15019, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28492224

RESUMO

Osteoarthritis (OA) is characterized by cartilage destruction and chondrocytes have a central role in this process. With age and inflammation chondrocytes have reduced capacity to synthesize and maintain ATP, a molecule important for cartilage homeostasis. Here we show that concentrations of ATP and adenosine, its metabolite, fall after treatment of mouse chondrocytes and rat tibia explants with IL-1ß, an inflammatory mediator thought to participate in OA pathogenesis. Mice lacking A2A adenosine receptor (A2AR) or ecto-5'nucleotidase (an enzyme that converts extracellular AMP to adenosine) develop spontaneous OA and chondrocytes lacking A2AR develop an 'OA phenotype' with increased expression of Mmp13 and Col10a1. Adenosine replacement by intra-articular injection of liposomal suspensions containing adenosine prevents development of OA in rats. These results support the hypothesis that maintaining extracellular adenosine levels is an important homeostatic mechanism, loss of which contributes to the development of OA; targeting adenosine A2A receptors might treat or prevent OA.


Assuntos
5'-Nucleotidase/genética , Adenosina/farmacologia , Artrite Experimental/tratamento farmacológico , Cartilagem Articular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Receptor A2A de Adenosina/genética , 5'-Nucleotidase/deficiência , Adenosina/metabolismo , Animais , Artrite Experimental/genética , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Condrócitos/metabolismo , Condrócitos/patologia , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Regulação da Expressão Gênica , Homeostase , Humanos , Injeções Intra-Articulares , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/farmacologia , Lipossomos/administração & dosagem , Masculino , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoartrite/tratamento farmacológico , Osteoartrite/genética , Osteoartrite/metabolismo , Osteoartrite/patologia , Ratos , Ratos Sprague-Dawley , Receptor A2A de Adenosina/deficiência , Transdução de Sinais , Tíbia/efeitos dos fármacos , Tíbia/metabolismo , Tíbia/patologia
5.
Med Anthropol ; 36(7): 615-628, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28328239

RESUMO

A growing corpus of anthropological scholarship demonstrates how science and medicine in Mexico are imbued by national concerns with modernization. Drawing on ethnographic research in a public hospital located in the south of Mexico City, I unpack one manifestation of this dynamic, which is the conjugation of the normal and the modern in Mexican reconstructive surgery. The aspiration toward normality underlies everyday clinic practices and relationships in this field, including why parents want surgery for their children and how doctors see their patients and their responsibilities toward them. It is also central to the professional ethic of reconstructive surgeons. I argue that the realities of health care provision in Mexico coalesced with this ethic to produce reconstructive surgeons as political subjects. They aimed to modernize craniofacial surgery in Mexico and so make the bodies of craniofacial patients normal.


Assuntos
Hospitais Públicos , Procedimentos de Cirurgia Plástica , Adulto , Antropologia Médica , Criança , Fenda Labial/etnologia , Fenda Labial/cirurgia , Fissura Palatina/etnologia , Fissura Palatina/cirurgia , Humanos , México/etnologia , Mudança Social
6.
Bioethics ; 31(2): 87-96, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28060429

RESUMO

Despite the growing importance of 'social value' as a central feature of research ethics, the term remains both conceptually vague and to a certain extent operationally rigid. And yet, perhaps because the rhetorical appeal of social value appears immediate and self-evident, the concept has not been put to rigorous investigation in terms of its definition, strength, function, and scope. In this article, we discuss how the anthropological concept of liminality can illuminate social value and differentiate and reconfigure its variegated approaches. Employing liminality as a heuristic encourages a reassessment of how we understand the mobilization of 'social value' in bioethics. We argue that social value as seen through the lens of liminality can provide greater clarity of its function and scope for health research. Building on calls to understand social value as a dynamic, rather than a static, concept, we emphasize the need to appraise social value iteratively throughout the entire research as something that transforms over multiple times and across multiple spaces occupied by a range of actors.


Assuntos
Bioética , Ética em Pesquisa , Religião e Psicologia , Valores Sociais , Humanos , Espiritualidade
7.
Med Anthropol Q ; 31(3): 385-402, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27550815

RESUMO

Plastic surgeons around the globe are implementing projects that mix audit with medical research to ensure and improve the level of care offered to patients with cleft lip and palate. Drawing on recent literature on "audit culture" and the global growth of "performance indicators" as a form of governance, I demonstrate the conjugation of ethics and the production of numerical indicators in cleft treatment. By standardizing documentation, cleft treatment audit programs facilitate evidence-based medicine and a form of reflexive self-governance. However, the abstraction that accompanies standardization is amplified as corollary data practices travel. In emerging as the answer to improving treatment, these projects lock out the politico-economic factors that mediate medical care in resource poor settings. This danger is compounded by the tendency of numerical governance to replace political conversation with technocratic expertise.


Assuntos
Fenda Labial , Fissura Palatina , Procedimentos de Cirurgia Plástica , Adolescente , Antropologia Médica , Criança , Fenda Labial/economia , Fenda Labial/etnologia , Fenda Labial/cirurgia , Fissura Palatina/economia , Fissura Palatina/etnologia , Fissura Palatina/cirurgia , Humanos , Auditoria Médica , México/etnologia , Procedimentos de Cirurgia Plástica/economia , Procedimentos de Cirurgia Plástica/ética
8.
Law Innov Technol ; 8(2): 149-176, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-28058061

RESUMO

Biomedicine and the life sciences continuously rearrange the relationship between culture and biology. In consequence, we increasingly look for a suitable regulatory response to reduce perceived uncertainty and instability. This article examines the full implications of this 'regulatory turn' by drawing on the anthropological concept of liminality. We offer the term 'regulatory compression' to characterise the effects of extant regulatory approaches on health research practices. With its focus on transformation and the 'in-between', liminality allows us to see how regulatory frameworks rely on a silo-based approach to classifying and regulating research objects such that they: (1) limit the flexibility necessary in clinical and laboratory research; (2) result in the emergence of unregulated spaces that lie between the bounded regulatory spheres; and (3) curtail modes of public participation in the health research enterprise. We suggest there is a need to develop the notion of 'processual regulation', a novel framework that requires a temporal-spatial examination of regulatory spaces and practices as these are experienced by all actors, including the relationship of actors with the objects of regulation.

11.
Front Physiol ; 6: 24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25759670

RESUMO

A key challenge for the physiology modeling community is to enable the searching, objective comparison and, ultimately, re-use of models and associated data that are interoperable in terms of their physiological meaning. In this work, we outline the development of a workflow to modularize the simulation of tissue-level processes in physiology. In particular, we show how, via this approach, we can systematically extract, parcellate and annotate tissue histology data to represent component units of tissue function. These functional units are semantically interoperable, in terms of their physiological meaning. In particular, they are interoperable with respect to [i] each other and with respect to [ii] a circuitboard representation of long-range advective routes of fluid flow over which to model long-range molecular exchange between these units. We exemplify this approach through the combination of models for physiology-based pharmacokinetics and pharmacodynamics to quantitatively depict biological mechanisms across multiple scales. Links to the data, models and software components that constitute this workflow are found at http://open-physiology.org/.

12.
Bull Math Biol ; 77(1): 23-45, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25515028

RESUMO

Internodons are a formalization of Hennig's concept of species. We present an alternative construction of internodons imposing a tree structure on the genealogical network. We prove that the segments (trivial unary trees) from this tree structure are precisely the internodons. We obtain the following spin-offs. First, the generated tree turns out to be an organismal tree of life. Second, this organismal tree is homeomorphic to the phylogenetic Hennigian species tree of life, implying the discovery of a multi-level tree of life: this phylogenetic tree can be obtained by zooming out from the organismal tree, or conversely, the organismal tree of life can be generated by expanding the phylogenetic nodes into unary trees. Finally, the definition of the organismal tree allows an efficient algorithmic transformation of a given genealogical network into its corresponding phylogenetic species tree of life. The latter will be presented in a separate paper.


Assuntos
Especiação Genética , Filogenia , Algoritmos , Animais , Feminino , Masculino , Conceitos Matemáticos , Modelos Genéticos
13.
Acta Biotheor ; 61(2): 181-201, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23297024

RESUMO

We argue that C. Darwin and more recently W. Hennig worked at times under the simplifying assumption of an eternal biosphere. So motivated, we explicitly consider the consequences which follow mathematically from this assumption, and the infinite graphs it leads to. This assumption admits certain clusters of organisms which have some ideal theoretical properties of species, shining some light onto the species problem. We prove a dualization of a law of T. A. Knight and C. Darwin, and sketch a decomposition result involving the internodons of D. Kornet, J. Metz and H. Schellinx. A further goal of this paper is to respond to B. Sturmfels' question, "Can biology lead to new theorems?"


Assuntos
Evolução Molecular , Biologia de Sistemas , Modelos Biológicos , Especificidade da Espécie
14.
PLoS One ; 6(7): e22040, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21789209

RESUMO

BACKGROUND: Organotypic brain slice culturing techniques are extensively used in a wide range of experimental procedures and are particularly useful in providing mechanistic insights into neurological disorders or injury. The cellular and morphological alterations associated with hippocampal brain slice cultures has been well established, however, the neuronal response of mouse cortical neurons to culture is not well documented. METHODS: In the current study, we compared the cell viability, as well as phenotypic and protein expression changes in cortical neurons, in whole brain slice cultures from mouse neonates (P4-6), adolescent animals (P25-28) and mature adults (P50+). Cultures were prepared using the membrane interface method. RESULTS: Propidium iodide labeling of nuclei (due to compromised cell membrane) and AlamarBlue™ (cell respiration) analysis demonstrated that neonatal tissue was significantly less vulnerable to long-term culture in comparison to the more mature brain tissues. Cultures from P6 animals showed a significant increase in the expression of synaptic markers and a decrease in growth-associated proteins over the entire culture period. However, morphological analysis of organotypic brain slices cultured from neonatal tissue demonstrated that there were substantial changes to neuronal and glial organization within the neocortex, with a distinct loss of cytoarchitectural stratification and increased GFAP expression (p<0.05). Additionally, cultures from neonatal tissue had no glial limitans and, after 14 DIV, displayed substantial cellular protrusions from slice edges, including cells that expressed both glial and neuronal markers. CONCLUSION: In summary, we present a substantial evaluation of the viability and morphological changes that occur in the neocortex of whole brain tissue cultures, from different ages, over an extended period of culture.


Assuntos
Envelhecimento/metabolismo , Córtex Cerebral/citologia , Neuroglia/citologia , Neurônios/citologia , Técnicas de Cultura de Órgãos/métodos , Animais , Animais Recém-Nascidos , Astrócitos/citologia , Astrócitos/metabolismo , Western Blotting , Morte Celular , Forma Celular , Células Cultivadas , Proteínas do Citoesqueleto/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/metabolismo , Neurônios/metabolismo
15.
J Oral Maxillofac Surg ; 64(1): 87-93, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16360862

RESUMO

PURPOSE: Extension of dental abscesses to distant areas of the head and neck has been repeatedly reported in the medical literature. Subsequent involvement of the orbit still remains a rarity, resulting in protracted onset of therapy because of inaccurate diagnosis. Considering the possible lasting damage that can result from insufficient therapy, like blindness or even death, the need to extensively educate practicing physicians becomes evident. MATERIALS AND METHODS: With the help of a comprehensive review of the medical literature underlined with a clinical case, the etiology, diagnosis, and therapy of the acute orbit are highlighted with emphasis on the new imaging modalities as well as the broad spectrum antibiotics currently available on the market. RESULTS: Orbital infections of odontogenic origin are the rarest sequelae, with a prevalence of 1.3%. Correct diagnosis, adequate antibiotic therapy, and surgical drainage are the keys to success. CONCLUSION: The acute orbit continues to be a medical challenge. With the proposed diagnostic and therapy guidelines, this affliction can be identified and contained with a high degree of certainty.


Assuntos
Abscesso/etiologia , Infecção Focal Dentária/complicações , Doenças Orbitárias/etiologia , Abscesso/diagnóstico , Abscesso/terapia , Antibacterianos/uso terapêutico , Drenagem , Infecção Focal Dentária/terapia , Humanos , Doenças Orbitárias/diagnóstico , Doenças Orbitárias/terapia , Tomografia Computadorizada por Raios X
16.
Reprod Biomed Online ; 8(4): 454-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15149570

RESUMO

Experience with conventional clinical IVF indicates that a first cleavage can occur in the absence of detectable pronuclear formation (so-called silent fertilization). In these instances, the first division is often asymmetrical and delayed when compared with normally fertilized siblings. In this study, DNA configurations and spindle organization were examined by fluorescence microscopy in metaphase II human oocytes that remained unfertilized after conventional IVF and were considered likely candidates for silent fertilization. The results show comparatively high frequencies of penetration in the absence of detectable pronuclear evolution, and that both a maternal meiotic and a sperm-derived mitotic-like spindle can coexist in the same oocyte. Patterns of cell division and blastomere nucleation in silent fertilizations suggest the possibility that this division may involve uniparental chromosomal segregation in which maternal and paternal DNA is differentially partitioned into daughter blastomeres. This pattern of inheritance may generate certain types of ploidy and nucleation defects detected at the 2- to 4-cell stage.


Assuntos
Núcleo Celular/ultraestrutura , Fertilização in vitro , Fertilização , Oócitos/ultraestrutura , Espermatozoides/ultraestrutura , Fuso Acromático/ultraestrutura , Blastômeros/ultraestrutura , Segregação de Cromossomos , DNA/metabolismo , Feminino , Humanos , Masculino , Metáfase , Microscopia Confocal , Microscopia de Fluorescência , Interações Espermatozoide-Óvulo , Fuso Acromático/metabolismo , Tubulina (Proteína)/metabolismo
17.
Hum Reprod ; 18(11): 2429-40, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14585897

RESUMO

BACKGROUND: The relative magnitude of the inner mitochondrial membrane potential (DeltaPsim) has been suggested to indicate the competence of mammalian gametes and early embryos. This study examined the response of cultured somatic cells and mouse oocytes to inhibitors and conditions that affect DeltaPsim or metabolism, or both, and measured treatment-specific changes in ATP and cytoplasmic free Ca(2+). METHODS: During and after treatment, relative DeltaPsim, free Ca(2+), and ATP levels and cortical granule density were determined. RESULTS: Comparable responses of somatic cells and metaphase II mouse oocytes to experimental manipulations that affect DeltaPsim and metabolism were observed and reversible loss of DeltaPsim was associated with increased intracellular free Ca(2+), which in certain instances resulted in parthenogenetic activation. CONCLUSION: The findings support a mitochondrial basis for pericortical J-aggregate fluorescence but not for a direct association between high DeltaPsim and metabolism. The results extend previous findings indicating that high-polarized (high DeltaPsim, JC-1 J-aggregate-forming) mitochondria occur in pericortical domains in mouse and human oocytes and early preimplantation stage embryos and support the notion that this spatial distribution may be related to localized ionic and metabolic regulation.


Assuntos
Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Citoplasma/metabolismo , Metáfase/fisiologia , Mitocôndrias/fisiologia , Oócitos/metabolismo , Animais , Benzimidazóis , Ácido Bongcréquico/farmacologia , Calcimicina/farmacologia , Carbocianinas , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Células Cultivadas , Exocitose/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Corantes Fluorescentes , Humanos , Membranas Intracelulares/metabolismo , Ionóforos/farmacologia , Potenciais da Membrana , Camundongos , Oligomicinas/farmacologia , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Temperatura
18.
Hum Reprod ; 17(2): 393-406, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11821285

RESUMO

BACKGROUND: The magnitude of the inner mitochondrial membrane potential (deltapsim) appears to influence the level of certain mitochondrial activities including regulation of ionic fluxes and ATP liberation, activities that are often compartmentalized or location dependent in cells. Recent evidence suggests that within cells, mitochondria can be heterogeneous with respect to deltapsim, and that high-polarized mitochondria (high deltapsim) may occur in the subplasmalemmal cytoplasm where intercellular contact is absent. Here, we investigated whether deltapsim in oocytes and preimplantation embryos was heterogeneous and cell contact-associated. METHODS: Mouse and human oocytes and preimplantation stage embryos stained with mitochondria-specific probes rhodamine 123, MitoTracker Orange, and the deltapsim-sensitive probe JC-1, (5,5',6,6'-tetrachloro-1,1,3,3'-tetraethylbenzimidazoylcarbocyanine iodide), were examined by epifluorescence, scanning laser confocal, and transmission electron microscopy. The possibility that intercellular contact and deltapsim are associated was examined for oocytes, where transzonal coronal cell contacts were terminated naturally or experimentally, and for intact, disaggregated, and reconstructed cleavage stage mouse embryos. RESULTS: For both oocytes and embryos, clusters of apparently high-polarized mitochondria occur in the pericortical cytoplasm in regions free from intercellular contact. CONCLUSIONS: The findings suggest that mitochondria in oocytes and preimplantation embryos may be heterogeneous with respect to deltapsim. We propose that high-polarized pericortical mitochondria may have a role in the acquisition of oocyte competence and the regulation of early developmental processes that may be associated with elevated metabolism or intracellular signalling through calcium-induced calcium release pathways.


Assuntos
Blastocisto/fisiologia , Mitocôndrias/fisiologia , Oócitos/fisiologia , Animais , Benzimidazóis , Blastocisto/ultraestrutura , Carbocianinas , Comunicação Celular/fisiologia , Senescência Celular/fisiologia , Feminino , Fluorescência , Corantes Fluorescentes , Humanos , Membranas Intracelulares/fisiologia , Potenciais da Membrana/fisiologia , Camundongos , Microscopia Confocal , Microscopia Eletrônica , Mitocôndrias/ultraestrutura , Oócitos/ultraestrutura , Rodamina 123 , Coloração e Rotulagem , Xantenos
19.
J Nematol ; 34(2): 130-4, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19265920

RESUMO

Current strategies for management of Pratylenchus penetrans in both white potato and tomato consist of the use of fumigant or non-fumigant nematicides or crop rotation. The objective of this study was to determine if double-cropping African marigolds (Tagetes erecta) with potatoes or tomatoes could reduce P. penetrans populations. Plots were 10 m x 3 m arranged in a randomized complete block design with four replications. Treatments included marigolds, potatoes or tomatoes, and natural weedy fallow followed by either potatoes or tomatoes. Nematode populations were sampled before spring planting, between crops in August and after harvest in November. During the 3 years of the study, P. penetrans soil population density declined by an average of 93% from the pre-plant level when marigold was grown in rotation with potato and by 98% when marigold was grown.in rotation with tomato. Weedy fallow preceding potato resulted in an average decline in P. penetrans soil population density of 38%, and a similar decrease (37%) was seen when fallow preceded tomato. There was a significant reduction in the number of P. penetrans found in both potato and tomato roots when the crops followed marigolds. These results suggest that P. penetrans population density may be significantly reduced when marigolds are double-cropped with potatoes or tomatoes.

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