Adherent Primary Cultures of Mouse Intercostal Muscle Fibers for Isolated Fiber Studies

Primary culture models of single adult skeletal muscle fibers dissociated from locomotor muscles adhered to glass coverslips are routine and allow monitoring of functional processes in living cultured fibers. To date, such isolated fiber cultures have not been established for respiratory muscles, despite the fact that dysfunction of core respiratory muscles leading to respiratory arrest is the most common cause of death in many muscular diseases. Here we present the first description of an adherent culture system for single adult intercostal muscle fibers from the adult mouse. This system allows for monitoring functional properties of these living muscle fibers in culture with or without electrical field stimulation to drive muscle fiber contraction at physiological or pathological respiratory firing patterns. We also provide initial characterization of these fibers, demonstrating several common techniques in this new model system in the context of the established Flexor Digitorum Brevis muscle primary culture model

Variability in presentation and management of gastric volvulus: report of 3 cases

Gastric volvulus is a pathology of acute or subacute presentation. Depending on the type, a gastric volvulus can present as an emergency if there is vascular compromise with necrosis and high risk of perforation and its surgical resolution is mandatory. Subacute gastric volvulus does not compromise the organ or organism urgently but is associated with high morbidity and should be resolved when the patient is in optimal conditions to offer definitive treatment. Depending on the torsion axis, it is classified as axial or mesenteroaxial organ, both merit reduction according to their presentation and the clinical context of the patient.

The deep inferior epigastric artery perforator flap: a review

Breast cancer is recognized worldwide as a major health problem among women due to its high incidence and high mortality and morbidity rates. Breast reconstruction is an approach of great value for those patients who underwent mastectomy, impacting their quality of life and psychological stress. The deep inferior epigastric artery perforator (DIEP) flap was described as the preferred graft for breast reconstruction with an autologous flap by surgeons because it represented a decrease in complications for the time and obtained better results. DIEP flap reconstruction requires microsurgical skills as well as continuous monitoring of the patient to identify and resolve possible associated complications.

Optimal spatiotemporal scales to aggregate satellite ocean color data for nearshore reefs and tropical coastal waters: two case studies

Remotely sensed ocean color data are useful for monitoring water quality in coastal environments. However, moderate resolution (hundreds of meters to a few kilometers) satellite data are underutilized in these environments because of frequent data gaps from cloud cover and algorithm complexities in shallow waters. Aggregating satellite data over larger space and time scales is a common method to reduce data gaps and generate a more complete time series, but potentially smooths out the small-scale, episodic changes in water quality that can have ecological influences. By comparing aggregated satellite estimates of Kd(490) with related in-water measurements, we can understand the extent to which aggregation methods are viable for filling gaps while being able to characterize ecologically relevant water quality conditions. In this study, we tested a combination of six spatial and seven temporal scales for aggregating data from the VIIRS instrument at several coral reef locations in Maui, Hawai‘i and Puerto Rico and compared these with in situ measurements of Kd(490) and turbidity. In Maui, we found that the median value of a 5-pixels, 7-days spatiotemporal cube of satellite data yielded a robust result capable of differentiating observations across small space and time domains and had the best correlation among spatiotemporal cubes when compared with in situ Kd(490) across 11 nearshore sites (R2 = 0.84). We also found long-term averages (i.e., chronic condition) of VIIRS data using this aggregation method follow a similar spatial pattern to onshore turbidity measurements along the Maui coast over a three-year period. In Puerto Rico, we found that the median of a 13-pixels, 13-days spatiotemporal cube of satellite data yielded the best overall result with an R2 = 0.54 when compared with in situ Kd(490) measurements for one nearshore site with measurement dates spanning 2016–2019. As spatiotemporal cubes of different dimensions yielded optimum results in the two locations, we recommend local analysis of spatial and temporal optima when applying this technique elsewhere. The use of satellite data and in situ water quality measurements provide complementary information, each enhancing understanding of the issues affecting coastal ecosystems, including coral reefs, and the success of management efforts

Shopping for Ecological Indices? On the Use of Incidence-Based Species Compositional Similarity Measures

β-diversity has been under continuous debate, with a current need to better understand the way in which a new wave of measures work. We assessed the results of 12 incidence-based β-diversity indices. Our results of gradual species composition overlap between paired assemblages considering progressive differences in species richness show the following: (i) four indices (β-2, β-3, β-3.s, and βr) should be used cautiously given that results with no shared species retrieve results that could be misinterpreted; (ii) all measures conceived specifically as partitioned components of species compositional dissimilarities ought to be used as such and not as independent measures per se; (iii) the non-linear response of some indices to gradual species composition overlap should be interpreted carefully, and further analysis using their results as dependent variables should be performed cautiously; and (iv) two metrics (βsim and βsor) behave predictably and linearly to gradual species composition overlap. We encourage ecologists using measures of β-diversity to fully understand their mathematical nature and type of results under the scenario to be used in order to avoid inappropriate and misleading inferences

Shopping for Ecological Indices? On the Use of Incidence-Based Species Compositional Similarity Measures

β-diversity has been under continuous debate, with a current need to better understand the way in which a new wave of measures work. We assessed the results of 12 incidence-based β-diversity indices. Our results of gradual species composition overlap between paired assemblages considering progressive differences in species richness show the following: (i) four indices (β-2, β-3, β-3.s, and βr) should be used cautiously given that results with no shared species retrieve results that could be misinterpreted; (ii) all measures conceived specifically as partitioned components of species compositional dissimilarities ought to be used as such and not as independent measures per se; (iii) the non-linear response of some indices to gradual species composition overlap should be interpreted carefully, and further analysis using their results as dependent variables should be performed cautiously; and (iv) two metrics (βsim and βsor) behave predictably and linearly to gradual species composition overlap. We encourage ecologists using measures of β-diversity to fully understand their mathematical nature and type of results under the scenario to be used in order to avoid inappropriate and misleading inferences

Uso y duración de terapia antibiótica en la exacerbación pulmonar aguda de la fibrosis quística: un tema aún sin definir

Cystic fibrosis is a condition about which not much is yet known and remains a hot topic in translational and pulmonary medicine. Evidence on the management of exacerbations is limited, with few clinical trials and systematic reviews. For example, the use and duration of antibiotics in this condition is unknown. Considering that this is a disease that entails high health costs and substantially decreases the functional capacity of the affected person, it is necessary to quickly establish practical algorithms based on evidence. Based on the above, the objective of this narrative review is to synthesize evidence on the use and duration of antibiotic therapy in acute pulmonary exacerbations in patients with cystic fibrosis. For this, a bibliographic search was carried out in the search engines and databases PubMed, ScienceDirect, Embase, EBSCO and MEDLINE. It was defined that any article related to the evaluation of the use and duration of antibiotic therapy in acute pulmonary exacerbation in patients with cystic fibrosis would be included, giving priority to original studies and systematic reviews and meta-analyses. After the review of the title and the summary of all the results, 42 articles were finally included. It was found that antibiotic therapy 10 days after standard treatment, by intravenous route, either doxycycline or azithromycin plus colistimethate, allows greater recovery of lost pulmonary function, lengthens the time until the next exacerbation and resolves symptoms quickly.La fibrosis quística es una enfermedad sobre la que aún no se sabe mucho y sigue siendo un tema candente en la medicina traslacional y pulmonar. La evidencia sobre el manejo de las exacerbaciones es limitada, con pocos ensayos clínicos y revisiones sistemáticas. Por ejemplo, se desconoce el uso y la duración de los antibióticos en esta enfermedad. Teniendo en cuenta que se trata de una enfermedad que supone un elevado coste sanitario y que disminuye sustancialmente la capacidad funcional del afectado, es necesario establecer rápidamente algoritmos prácticos basados en la evidencia. En base a lo anterior, el objetivo de esta revisión narrativa es sintetizar evidencia sobre el uso y la duración del tratamiento antibiótico en las exacerbaciones pulmonares agudas en pacientes con fibrosis quística. Para esto, se llevó a cabo una búsqueda bibliográfica en los motores de búsqueda y bases de datos bases de datos PubMed, ScienceDirect, Embase, EBSCO y MEDLINE. Se definió que cualquier artículo relacionado con la evaluación del uso y duración de antibioticoterapia en la exacerbación aguda pulmonar del paciente con fibrosis quística, sería incluido, dando prioridad a los estudios originales y a las revisiones sistemáticas y meta-análisis. Posterior a la revisión del título y resumen de todos los resultados, se incluyeron 42 artículos. Se encontró que instaurar antibioticoterapia 10 días posterior al tratamiento estándar, por vía intravenosa, ya sea de doxiciclina o azitromicina más colistimetato, permite obtener mayor recuperación de la función pulmonar perdida, alargar el tiempo hasta la próxima exacerbación y solucionar sintomatología rápidamente

Mice Null for Calsequestrin 1 Exhibit Deficits in Functional Performance and Sarcoplasmic Reticulum Calcium Handling

In skeletal muscle, the release of calcium (Ca2+) by ryanodine sensitive sarcoplasmic reticulum (SR) Ca2+ release channels (i.e., ryanodine receptors; RyR1s) is the primary determinant of contractile filament activation. Much attention has been focused on calsequestrin (CASQ1) and its role in SR Ca2+ buffering as well as its potential for modulating RyR1, the L-type Ca2+ channel (dihydropyridine receptor, DHPR) and other sarcolemmal channels through sensing luminal [Ca2+]. The genetic ablation of CASQ1 expression results in significant alterations in SR Ca2+ content and SR Ca2+ release especially during prolonged activation. While these findings predict a significant loss-of-function phenotype in vivo, little information on functional status of CASQ1 null mice is available. We examined fast muscle in vivo and in vitro and identified significant deficits in functional performance that indicate an inability to sustain contractile activation. In single CASQ1 null skeletal myofibers we demonstrate a decrease in voltage dependent RyR Ca2+ release with single action potentials and a collapse of the Ca2+ release with repetitive trains. Under voltage clamp, SR Ca2+ release flux and total SR Ca2+ release are significantly reduced in CASQ1 null myofibers. The decrease in peak Ca2+ release flux appears to be solely due to elimination of the slowly decaying component of SR Ca2+ release, whereas the rapidly decaying component of SR Ca2+ release is not altered in either amplitude or time course in CASQ1 null fibers. Finally, intra-SR [Ca2+] during ligand and voltage activation of RyR1 revealed a significant decrease in the SR[Ca2+]free in intact CASQ1 null fibers and a increase in the release and uptake kinetics consistent with a depletion of intra-SR Ca2+ buffering capacity. Taken together we have revealed that the genetic ablation of CASQ1 expression results in significant functional deficits consistent with a decrease in the slowly decaying component of SR Ca2+ release

A Proof-Of-Principle Study of Epigenetic Therapy Added to Neoadjuvant Doxorubicin Cyclophosphamide for Locally Advanced Breast Cancer

BACKGROUND: Aberrant DNA methylation and histone deacetylation participate in cancer development and progression; hence, their reversal by inhibitors of DNA methylation and histone deacetylases (HDACs) is at present undergoing clinical testing in cancer therapy. As epigenetic alterations are common to breast cancer, in this proof-of-concept study demethylating hydralazine, plus the HDAC inhibitor magnesium valproate, were added to neoadjuvant doxorubicin and cyclophosphamide in locally advanced breast cancer to assess their safety and biological efficacy. METHODOLOGY: This was a single-arm interventional trial on breast cancer patients (ClinicalTrials.gov Identifier: NCT00395655). After signing informed consent, patients were typed for acetylator phenotype and then treated with hydralazine at 182 mg for rapid-, or 83 mg for slow-acetylators, and magnesium valproate at 30 mg/kg, starting from day –7 until chemotherapy ended, the latter consisting of four cycles of doxorubicin 60 mg/m(2) and cyclophosphamide 600 mg/m(2) every 21 days. Core-needle biopsies were taken from primary breast tumors at diagnosis and at day 8 of treatment with hydralazine and valproate. MAIN FINDINGS: 16 patients were included and received treatment as planned. All were evaluated for clinical response and toxicity and 15 for pathological response. Treatment was well-tolerated. The most common toxicity was drowsiness grades 1–2. Five (31%) patients had clinical CR and eight (50%) PR for an ORR of 81%. No patient progressed. One of 15 operated patients (6.6%) had pathological CR and 70% had residual disease <3 cm. There was a statistically significant decrease in global 5(m)C content and HDAC activity. Hydralazine and magnesium valproate up- and down-regulated at least 3-fold, 1,091 and 89 genes, respectively. CONCLUSIONS: Hydralazine and magnesium valproate produce DNA demethylation, HDAC inhibition, and gene reactivation in primary tumors. Doxorubicin and cyclophosphamide treatment is safe, well-tolerated, and appears to increase the efficacy of chemotherapy. A randomized phase III study is ongoing to support the efficacy of so-called epigenetic or transcriptional cancer therapy