ATP released during hypoxia from the ventrolateral medulla activates purinergic receptors (P2Rs) to attenuate the secondary hypoxic depression of breathing by a mechanism that likely involves a P2Y 1 R-mediated excitation of preBötzinger complex (preBötC) inspiratory rhythm-generating networks. In this study, we used rhythmically active in vitro preparations from embryonic and postnatal rats and ATP microinjection into the rostral ventral respiratory group (rVRG)/preBötC to reveal that these networks are sensitive to ATP when rhythm emerges at embryonic day 17 (E17). The peak frequency elicited by ATP at E19 and postnatally was the same (ϳ45 bursts/min), but relative sensitivity was threefold greater at E19, reflecting a lower baseline frequency (5.6 Ϯ 0.9 vs 19.0 Ϯ 1.3 bursts/min). Combining microinjection techniques with ATP biosensors revealed that ATP concentration in the rVRG/preBötC falls rapidly as a result of active processes and closely correlates with inspiratory frequency. A phosphate assay established that preBötC-containing tissue punches degrade ATP at rates that increase perinatally. Thus, the agonist profile [ATP/ADP/adenosine (ADO)] produced after ATP release in the rVRG/preBötC will change perinatally. Electrophysiology further established that the ATP metabolite ADP is excitatory and that, in fetal but not postnatal animals, ADO at A 1 receptors exerts a tonic depressive action on rhythm, whereas A 1 antagonists extend the excitatory action of ATP on inspiratory rhythm. These data demonstrate that ATP is a potent excitatory modulator of the rVRG/preBötC inspiratory network from the time it becomes active and that ATP actions are determined by a dynamic interaction between the actions of ATP at P2 receptors, ectonucleotidases that degrade ATP, and ATP metabolites on P2Y and P1 receptors.
BackgroundTo analyze the characteristics and outcomes of women with breast cancer in the Northern Alberta Health Region (NAHR) who declined recommended primary standard treatments.MethodsA chart review was performed of breast cancer patients who refused recommended treatments during the period 1980 to 2006. A matched pair analysis was performed to compare the survival data between those who refused or received standard treatments.ResultsA total of 185 (1.2%) patients refused standard treatment. Eighty-seven (47%) were below the age of 75 at diagnosis. The majority of those who refused standard treatments were married (50.6%), 50 years or older (60.9%), and from the urban area (65.5%). The 5-year overall survival rates were 43.2% (95% CI: 32.0 to 54.4%) for those who refused standard treatments and 81.9% (95% CI: 76.9 to 86.9%) for those who received them. The corresponding values for the disease-specific survival were 46.2% (95% CI: 34.9 to 57.6%) vs. 84.7% (95% CI: 80.0 to 89.4%).ConclusionsWomen who declined primary standard treatment had significantly worse survival than those who received standard treatments. There is no evidence to support using Complementary and Alternative Medicine (CAM) as primary cancer treatment.
There is an unmet demand for partial breast reconstruction, with an opportunity to advocate and increase awareness on behalf of patients undergoing breast conservation therapy.
Introduction There is an ongoing shortage of burn specialists, and workforce reports suggest possible hurdles attracting plastic surgeons into burn care. The purpose of this study was to (1) determine the state of burn care in plastic surgery residency and (2) identify what barriers might exist for plastic surgeons pursuing a practice that involves burn care. Methods Surveys were distributed to North American plastic surgery program directors and residents, respectively, during the 2018–2019 academic year. Results Fifty-eight program directors (response, 54%) and 320 plastic surgery residents (response, 30%) participated. Burn care was felt to be an important component in training by most program directors (USA, 88%; Canada, 100%) and residents (USA, 87%; Canada, 99%). The majority of program directors included a burn unit rotation (USA, 88%; Canada, 90%). Rotations for integrated residents averaged 2.5 months and most commonly occurred during second year; independent residents spent 1.2 months on rotation, usually in first year. Three-quarters of American residents were interested in a career that involves burn care in some capacity, primarily burn reconstruction (40%). Factors that would discourage a trainee from practicing burn care in the future included the nature of burn care (60%) and burn operations (45%), the on-call commitment (39%), and a narrow scope of practice (38%). Discussion This study challenges the belief that plastic surgery trainees are disinterested in burn care. Burn surgery remains an important component of training programs, and we propose several steps to encourage greater interest and participation in the burn surgery workforce.
In contrast to the well-established association between ultraviolet radiation (UVR) exposure and skin cancers, the relationship between UVR and uveal malignant melanoma (UM) remains controversial. To address this controversy, we evaluated the incidence rates of cutaneous malignancies in the eyelids as a proxy for UVR exposure in the ocular region using a population-based cancer registry. Overall, 74,053 cases of eyelid basal cell carcinoma (BCC) and 7890 cases of melanoma over a 26-year period (1982–2007) were analyzed. The incidence of eyelid basal cell carcinoma and uveal melanoma remained stable, whereas other cutaneous areas demonstrated an increase in the rates. A comparability test demonstrated that BCC incidence trends were significantly different between the eyelid versus both chronically exposed (males p = 0.001; females p = 0.01) and intermittently exposed skin (males and females, p = 0.0002), as well as the skin of the face (males p = 0.002; females p = 0.02). Similarly, melanoma trends were significantly different between the UM group versus both chronically exposed cutaneous melanoma (CM) (males p = 0.001; females p = 0.04) and intermittently exposed CM (males p = 0.005), as well as facial skin CM (males and females p = 0.0002). The discrepancy of cancer incidence between tumors in the peri-ocular region versus the rest of the body suggests that the peri-ocular region might have a different or unique exposure pattern to ultraviolet radiation.
Background Orbital compartment syndrome (OCS) is a rare but devastating complication of over-resuscitation in burn patients that may lead to permanent visual loss. The purpose of this study was to (1) present a series of burn patients with OCS, and (2) survey practice patterns of monitoring intra-ocular pressure (IOP) during burn resuscitation. Methods Cases of OCS at two American Burn Association (ABA)-verified burn centers were retrospectively reviewed. Patients were included if they (a) required lateral canthotomy/cantholysis for elevated IOPs, or (b) developed blindness during admission unrelated to any other ocular pathology. Data was collected on demographics, burn characteristics, fluid administration, ophthalmologic findings and complications. An eight-item electronic survey was distributed by email through the ABA to all physician members. Results Twelve patients with OCS were identified, with a mean age of 47.8 ±12.4 years and TBSA of 63.7 ±18.6%. Mean fluid resuscitation at 24 hours was 4.9 ±1.6 mL/kg/%TBSA, or 0.29 ±0.06 L/kg. Eight patients underwent canthotomy/cantholysis for OCS, while four were later found to have visual loss. A total of 83 (14%) ABA physicians responded to the survey. IOP was routinely measured by 23% of respondents during acute burn resuscitation. Conclusions OCS appears to have developed despite a relatively low 24-hour mL/kg/% burn resuscitation volume, but with a relatively higher cumulative (L/kg) fluid volume. Our survey found that monitoring of IOP during burn resuscitation is not routinely performed by the majority of providers. Taken together, the present study suggests clinical guidelines to recognize this complication of over-resuscitation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.