RESUMEN
Effective conservation requires an understanding not only of contemporary vegetation distributions in the landscape, but also cognizance of vegetation transitions over time with the goal of maintaining persistence of all states within the landscape. Using a state and transition model framework, we investigated temporal transitions over 31 years in species composition among five upland swamp vegetation communities in southeastern Australia. We applied fuzzy clustering to document transitions across communities; evaluated the resilience and resistance of communities to change; and explored the relationship between ecosystem states and major environmental factors posited to structure the system. We also evaluated the predictive ability of an established vegetation dynamics model. We found that community composition remained stable or underwent reversible or directional transitions depending on the vegetation type. Wetter communities (Ti-tree thicket and Cyperoid heath) were more stable (i.e., resistant) while drier communities showed a greater propensity to transition (i.e., had lower resistance) under the observed disturbance regime (low variance fire intervals). The resilience of drier communities differed under this regime, with Banksia thicket showing reversible compositional change, while Restioid heath and Sedgeland showed directional change. In accord with an established conceptual model, we found that communities were distributed along a hydrological gradient. In addition, vegetation structure, along with light penetration to ground level, differentiated communities. However, internal dynamics of drier communities were complex: differences in fire regime (penultimate fire interval in 2014 and number of fires since 1965) were unable to predict differences in community membership among sites. Aspects of the fire regime are expected to be more important predictors if fire intervals vary more strongly among sites in the future. Fuzzy clustering of compositional data allows managers to track community transitions over time and facilitates planned interventions for conservation purposes.
Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Plantas , Humedales , Biota , Nueva Gales del Sur , Dinámica Poblacional , Estaciones del AñoRESUMEN
Heterotopic ossification (HO) is defined as 'bone where it does not belong'. Given the historical variety of nomenclature and eponyms, there is significant confusion about the etiology, pathogenesis, classification, and treatment of HO related to the temporomandibular joint (TMJ). The existing classifications for TMJ HO have shortcomings: they relate to specific populations, use differing imaging studies and demographic data, do not universally include alloplastic/autologous replacements, are based variously on radiological and/or clinical presentations that cannot always be combined, and were largely developed to assist oral and maxillofacial surgeons in surgical management. These deficiencies make it problematic to compare studies, draw valid conclusions, and pursue research. The aim of this study was to develop a new, more inclusive classification for TMJ HO. Currently available classifications were evaluated and a Delphi-type system used to build consensus from clinicians and researchers to develop a new system. Fourteen unique classifications for TMJ ankylosis/HO were identified. In light of the biological specifics related to heterotopic calcification of extracellular matrix versus heterotopic formation of actual bone, the group recommends a more unambiguous term - peri-articular bone formation - and proposes a new classification. This will help clinicians and researchers to study, describe, and manage various types of ectopic bone associated with the TMJ.
Asunto(s)
Anquilosis , Osificación Heterotópica , Trastornos de la Articulación Temporomandibular , Humanos , Osteogénesis , Consenso , Técnica Delphi , Articulación Temporomandibular/cirugía , Trastornos de la Articulación Temporomandibular/patología , Osificación Heterotópica/cirugía , Anquilosis/cirugíaRESUMEN
There are few animal models for heterotopic ossification of the temporomandibular joint (TMJ-HO). This scoping review provides an overview of current knowledge on the induction methods and specific conditions required to produce TMJ-HO in various animal models. Two independent reviewers selected papers from the PubMed, Web of Science, and Cochrane Library databases. The inclusion criteria were articles in English, in vivo studies, and a TMJ-HO induction method. Observational, in vitro, human studies, reviews, and book chapters were excluded. Twenty-four publications were included. HO was surgically, genetically, or chemically induced through single or combined defects in the condyle, articular disc, and temporal bone in animal models (sheep=9 studies, mouse=5, rat=4, rabbit=2, pig=2, goat=1, dog=1, monkey=1) specific for traumatic TMJ-HO (n=4), ankylosis (n=9), osteoarthritis (n=8), experimental disc perforation (n=1), status post-TMJ replacement (n=1), and status post bilateral sagittal split osteotomy (n=1). TMJ-HO remains challenging to study due to its multifactorial etiology and largely unknown pathogenesis, which varies between species. There is a need for more accurate, reproducible animal models that can be extrapolated to human TMJ-HO and a consolidated clinical classification system to allow for meaningful future research.
RESUMEN
Surgery is an effective modality to reduce pain and increase range of motion (ROM) in TMJ disorders. The aim of this study was to determine which comorbidities and risk factors affect outcomes and progression to total joint replacement (TJR). A retrospective cohort study of patients who underwent TJR between 2000- 2018 at MGH was conducted. Primary outcome was successful vs unsuccessful surgery. Success was defined as pain score ≤ 4 and ROM ≥ 30 mm; failure was defined as lack of either or both. Secondary outcome was differences between patients undergoing TJR only (group A) and those undergoing multiple surgeries progressing to TJR (group B). 99 patients (82 females, 17 males) were included. Mean follow-up was 4.1 years; mean age at first surgery was 34.2 (range 14-71) years. Unsuccessful outcomes were associated with high preoperative pain, low preoperative ROM, and higher number of surgeries. Male sex favored successful outcome. 75.0% group A and 47.6% group B had successful outcome. Group B had more females, higher postoperative pain, lower postoperative ROM, and used more opioids compared to group A. High preoperative pain, low preoperative ROM, and more surgeries were associated with poorer outcomes and frequent opioid use.
Asunto(s)
Prótesis Articulares , Articulación Temporomandibular , Femenino , Humanos , Masculino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Factores de Riesgo , Dolor Postoperatorio , Resultado del Tratamiento , Rango del Movimiento ArticularRESUMEN
More than half of global wetlands have been lost because of anthropogenic disturbance, with the trend of decline continuing in the 21st century. While much of this loss relates to changes in surface flows, groundwater is also critical to sustaining wetland hydrology. Underground longwall mines extract coal seams, in turn fracturing the overlying stratigraphy, influencing aquifer connectivity and affecting surface flows via subsidence disturbance. Crucially, this subterranean disturbance may disrupt the hydrological processes that sustain freshwater wetlands at the surface. Here we present a new designed empirical study that compares the persistence of soil moisture after a rainfall event in wetlands subject to underground longwall coal mining to that in unmined reference wetlands. Accelerated Failure Time models showed that mined wetlands were persistently drier, retained water for shorter durations and exhibited less spatial differentiation than unmined wetlands. This quantitative evidence of severe, persistent hydrological change following resource extraction reinforces earlier observations and has important implications for biodiversity and provision of ecosystem services to a large urban population. If Ecologically Sustainable Development (ESD) outcomes and effective deployment of the mitigation hierarchy are to be achieved in line with current legislative and policy paradigms, our results highlight the need for more emphasis on impact avoidance and minimisation than restoration or offsetting to protect water and biodiversity values. Given severe constraints on restoration success, greater emphasis on avoidance in mine design and approval processes offers realistic opportunities for an improved balance between sustaining irreplaceable public assets and short-term benefits from non-renewable resource extraction.
RESUMEN
Oceania is a diverse region encompassing Australia, Melanesia, Micronesia, New Zealand, and Polynesia, and it contains six of the world's 39 hotspots of diversity. It has a poor record for extinctions, particularly for birds on islands and mammals. Major causes include habitat loss and degradation, invasive species, and overexploitation. We identified six major threatening processes (habitat loss and degradation, invasive species, climate change, overexploitation, pollution, and disease) based on a comprehensive review of the literature and for each developed a set of conservation policies. Many policies reflect the urgent need to deal with the effects of burgeoning human populations (expected to increase significantly in the region) on biodiversity. There is considerable difference in resources for conservation, including people and available scientific information, which are heavily biased toward more developed countries in Oceania. Most scientific publications analyzed for four threats (habitat loss, invasive species, overexploitation, and pollution) are from developed countries: 88.6% of Web of Science publications were from Australia (53.7%), New Zealand (24.3%), and Hawaiian Islands (10.5%). Many island states have limited resources or expertise. Even countries that do (e.g., Australia, New Zealand) have ongoing and emerging significant challenges, particularly with the interactive effects of climate change. Oceania will require the implementation of effective policies for conservation if the region's poor record on extinctions is not to continue.
Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ambiente , Animales , Contaminación Ambiental , Humanos , OceaníaRESUMEN
Certain anticonvulsant drugs, especially phenytoin and phenobarbital, interfere with vitamin K metabolism as indicated by a raised serum osteocalcin level. This finding may be of importance in the pathogenesis of side effects of these medications.
Asunto(s)
Anticonvulsivantes/farmacología , Proteínas de Unión al Calcio/sangre , Vitamina K/metabolismo , Adolescente , Adulto , Envejecimiento , Anticonvulsivantes/uso terapéutico , Niño , Preescolar , Interacciones Farmacológicas , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Osteocalcina , Fenobarbital/farmacología , Fenitoína/farmacología , Convulsiones/tratamiento farmacológicoRESUMEN
Histochemical and chemical techniques have been used to identify, isolate and characterize elastin from certain bovine cartilages. The results strongly suggest that in addition to fibroblasts and smooth muscle cells, chondroblasts also synthesize elastin. Some of the possible functions of elastin in elastic cartilages are discussed and the possiblity of a new type of elastin perhaps unique to cartilage is suggested.
Asunto(s)
Cartílago/análisis , Elastina/análisis , Aminoácidos/análisis , Amoníaco , Animales , Cartílago/citología , Bovinos , Cianuros , Oído/citología , Epiglotis/citología , Histocitoquímica , Laringe/citología , Coloración y EtiquetadoRESUMEN
We report on several relatives in 5 generations of one family with prominence of the ears, with a marked constriction at the junction between the lower and middle thirds of the pinna. Computerized tomography and radiographs in the propositus and his affected father showed abnormalities of the condyle of the mandible. The propositus had more severe changes in the condyle with microstomia and reduced range of motion of the mandible in the temporomandibular joint. There was no hearing loss or abnormalities of the bones of the middle ear.
Asunto(s)
Oído Externo/anomalías , Cóndilo Mandibular/anomalías , Niño , Oído Externo/diagnóstico por imagen , Humanos , Masculino , Cóndilo Mandibular/diagnóstico por imagen , Microstomía/diagnóstico por imagen , Microstomía/genética , Microstomía/patología , Radiografía , Síndrome , Articulación Temporomandibular/anomalías , Tomografía Computarizada de EmisiónRESUMEN
Epacris stuartii (Epacridaceae) is an endangered heathland shrub in which seedling recruitment occurs almost exclusively after fire. Seed viability and multiple seed dormancy mechanisms were examined to explore why levels of seedling recruitment were low after some fires, despite high rates of pre-fire seed production. The individual and combined effects of heat shock, smoke derivatives and darkness on germination were tested in the laboratory using an orthogonal logit-linear model, a form of analysis ideally suited to hypotheses concerning multiple germination cues. Seed viability (56%) was found not to be limiting. After 89 days of incubation, germination was significantly enhanced by heat shock, smoke treatment and continuous darkness but there were no significant interactions. These effects were equal in magnitude and additive such that maximum germination (42% of viable seeds) was stimulated when all three treatments were combined, significantly less germination occurred in response to any two treatments combined (22-23%), any single treatment stimulated germination at levels (10-11%) significantly less than two treatments and the lowest levels of germination occurred among untreated seeds (4%). Relative to the untreated control, germination was stimulated by smoke derivatives in high concentrations but not in low concentrations. The effect of darkness diminished with time so that after 270 days of incubation darkness had no significant effect on germination, while heat and smoke still enhanced germination significantly, additively and interchangeably. More prolonged germination of seeds exposed to light on the soil surface than buried seed may spread the risk of desiccation of emerging seedlings over multiple rainfall events. The role of heat and smoke derivates suggests that fire management is a crucial tool for influencing seedling recruitment and hence the survival of E. stuartii at its only known location.
RESUMEN
The human organotypic skin explant culture (hOSEC) model is a promising alternative in vitro model for screening contact allergens. In this model, the chemical-induced migration of Langerhans cells (LCs) out of the epidermis, evaluated after a 24-h exposure period, is used as a measure of sensitizer potential. As skin irritants can also induce LC migration it is essential that concentrations of test chemicals are used that are not even weakly irritant. Using the hOSEC irritation model chemicals are classified as weak irritants if they are toxic after a 48-h exposure period. Toxicity is determined by methyl green-pyronine (MGP) staining of hOSEC. We studied three frequently used non-sensitizing skin irritants and six potent or frequent human sensitizers in a dose-response. A complete discrimination between non-sensitizers and contact sensitizers was obtained for the chemicals tested when the concentrations used were lower than the weak irritant concentrations. Frequency of positive allergen reactions in patch test of human populations correlated with the difference between weak irritant concentrations and the lowest concentration inducing significant LC migration. Sensitizer potency correlated with chemical irritancy as determined by keratinocyte death. For the compounds tested, the hOSEC model predicted allergenicity in humans better than the guinea pig maximization test and the mouse local lymph node assay.
Asunto(s)
Alérgenos/toxicidad , Epidermis/efectos de los fármacos , Inmunización , Irritantes/toxicidad , Células de Langerhans/efectos de los fármacos , Alérgenos/clasificación , Alternativas a las Pruebas en Animales , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Epidermis/patología , Femenino , Humanos , Irritantes/clasificación , Células de Langerhans/patologíaRESUMEN
Subjects taking the anticonvulsant phenytoin were examined for gingival enlargement and skin-fold thickness. Induced synthesis of their hepatic microsomal enzymes was estimated by measuring urinary D-glucaric acid. Gingival enlargement was positively correlated (p less than 0.05) with urinary D-glucaric acid. Although skin-fold thickness was not correlated with either urinary D-glucaric acid or gingival enlargement, mean gingival enlargement was greater in some subjects who did have an increased skin thickness than in those with normal skin thickness. The results suggest that induction of microsomal enzyme synthesis, as estimated by urinary D-glucaric acid, is related to taking phenytoin, as is gingival enlargement, and that there are other factors that affect both phenomena.
Asunto(s)
Encía/crecimiento & desarrollo , Microsomas Hepáticos/enzimología , Fenitoína/efectos adversos , Adolescente , Adulto , Niño , Preescolar , Inducción Enzimática/efectos de los fármacos , Femenino , Encía/efectos de los fármacos , Ácido Glucárico/análogos & derivados , Ácido Glucárico/orina , Humanos , Masculino , Grosor de los Pliegues CutáneosRESUMEN
AIMS: Chronic neurogenic facial pain is commonly resistant to treatment and is often the source of significant patient morbidity. Adrenergic mechanisms are postulated to play a role in producing this type of pain, and adrenergic blocking agents are frequently used in clinical practice for pain control therapy. The analgesic effectiveness of an adrenergic blocking agent, intravenous phentolamine, was compared to saline and intravenous lidocaine in the present study using a single-blind protocol in patients with chronic neurogenic facial pain. METHODS: Thirty patients were studied whose common clinical features included pain for more than 6 months, unilateral trigeminal distribution, constant dysesthesia, and no evidence of pathology or known etiology. Phentolamine (30 mg), lidocaine (100 mg), and saline were each infused over periods of 5 to 10 minutes. Pain ratings were assessed every 4 minutes throughout each study period using a 10-point pain intensity scale. RESULTS: No patient reported subjective improvement of pain during or immediately following phentolamine or saline infusions alone. Sixteen of the 30 patients reported decreased pain following lidocaine infusion. In the majority of the patients, the duration of lidocaine analgesia was less than 30 minutes; however, some patients reported decreased pain for a longer time. CONCLUSION: The results do not support an adrenergic mechanism for chronic neurogenic facial pain. The response to lidocaine, a nonadrenergic, membrane-stabilizing agent, suggests that it may have clinical effectiveness in certain neurogenic facial pain patients.
Asunto(s)
Antagonistas Adrenérgicos alfa/administración & dosificación , Dolor Facial/tratamiento farmacológico , Fentolamina/administración & dosificación , Neuralgia del Trigémino/tratamiento farmacológico , Adulto , Anciano , Anestésicos Locales/administración & dosificación , Causalgia/tratamiento farmacológico , Enfermedad Crónica , Dolor Facial/etiología , Femenino , Humanos , Infusiones Intravenosas , Lidocaína/administración & dosificación , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/complicaciones , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Dimensión del Dolor , Método Simple Ciego , Encuestas y Cuestionarios , Sistema Nervioso Simpático/fisiopatología , Insuficiencia del TratamientoRESUMEN
Six cases are reported in which the primary complaint was episodic, recurrent facial pain that was triggered by a taste stimulus. The pain first occurred days to weeks after head and neck surgery. Patients reported that a food stimulus placed in the mouth evoked episodic, electric shock-like pain in a preauricular location on the surgical side. The smell of food or, less reliably, emotional excitement could also trigger pain. Mandibular movement did not evoke the pain, and between lancinating attacks there was either no pain or only mild discomfort. Following an episode of pain, there was a refractory period during which the pain could not be elicited. Physical examination demonstrated a preauricular sensory loss of variable distribution. No abnormal sweating or vasomotor findings were clinically apparent. No odontogenic, muscular, salivary gland, neurologic, or psychologic pathology was found to explain the clinical symptoms. The pain was not relieved with standard doses of anticonvulsants that are commonly used to treat trigeminal neuralgia. The duration of the recurrent pain symptoms in this group was 8 to 132 months without remission. Gustatory neuralgia may be a discrete syndrome that results from abnormal interactions between salivary efferent fibers and trigeminal sensory afferent fibers in the injured auriculotemporal nerve. The unique features of the disorder make it a potentially useful clinical model for the investigation of autonomic/sensory interactions in neuropathic pain.
Asunto(s)
Enfermedades de los Nervios Craneales/etiología , Dolor Facial/etiología , Neuralgia/etiología , Procedimientos Quirúrgicos Orales/efectos adversos , Dolor Postoperatorio/etiología , Adulto , Enfermedades de los Nervios Craneales/diagnóstico , Diagnóstico Diferencial , Ingestión de Alimentos , Femenino , Alimentos/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Glándula Parótida/fisiopatología , Estudios Retrospectivos , Sudoración Gustativa/fisiopatología , Neuralgia del Trigémino/diagnósticoRESUMEN
The vitamin K-dependent hemostatic factors are present in reduced quantities at birth and may decrease further in the first few days of life. Administration of vitamin K1 on day 1 prevents hemorrhagic disease of the newborn. Maternal ingestion of anticonvulsants puts the newborn at greater risk from hemorrhage, possibly as a result of induction of fetal microsomal enzymes with a resultant increased oxidative degradation of vitamin K which gives rise to a vitamin K deficiency and other concomitant clinical results, for example skeletal defects. Evidence for this sequence of events is presented and the widespread effect of vitamin K deficiency on the fetus is discussed.
Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Huesos/anomalías , Fenitoína/efectos adversos , Sangrado por Deficiencia de Vitamina K/inducido químicamente , Deficiencia de Vitamina K/inducido químicamente , Animales , Factores de Coagulación Sanguínea/fisiología , Embrión de Pollo , Femenino , Hemostasis/efectos de los fármacos , Humanos , Intercambio Materno-Fetal , Microsomas Hepáticos/enzimología , Oxidación-Reducción , Embarazo , Vitamina K 1/uso terapéutico , Sangrado por Deficiencia de Vitamina K/tratamiento farmacológico , Warfarina/farmacologíaRESUMEN
Elastin was isolated and purified by a procedure which sequentially removed lipids, collagen, structural glycoproteins and the microfibrillar proteins. Crosslinking profiles were obtained by column chromatography either after reduction with 3[H]NaBH4 or after reaction with 14[C]NaCN and NH3. Examination of the crosslinking profiles of the elastins from various tissue regions revealed differences in the type, distribution and quality of crosslinks.
Asunto(s)
Elastina , Pulmón/análisis , Animales , Bronquios/análisis , Bovinos , Desmosina , Oxidación-Reducción , Pleura/análisis , Tráquea/análisisRESUMEN
The differential diagnosis of pain in the face and dysfunction of the masticatory system is complex. Although most diagnoses are readily made, common symptoms can occasionally belie more serious diseases. Each patient was originally treated for TMJ dysfunctions and subsequently was diagnosed as suffering from pathosis of the infratemporal space.
Asunto(s)
Actinomicosis Cervicofacial/diagnóstico , Neoplasias de Cabeza y Cuello/diagnóstico , Trastornos de la Articulación Temporomandibular/diagnóstico , Adenocarcinoma/diagnóstico , Carcinoma/diagnóstico , Niño , Diagnóstico Diferencial , Dolor Facial/diagnóstico , Femenino , Fibrosarcoma/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Hueso TemporalRESUMEN
Injuries to the temporomandibular joint can range from contusion to complex displaced fractures. Major factors in the treatment of any injury are the patient's age and the stage in development of the temporomandibular joint and surrounding structures. A failure to diagnosis or the lack of proper treatment may lead to deformities. Following initial evaluation and management, vigorous mobilization of the joint remains a cornerstone of treatment.