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1.
J Bioeth Inq ; 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37930560

RESUMEN

Feelings of guilt are human emotions that may arise if a person committed an action that contradicts basic moral mores or failed to commit an action that is considered moral according to their ethical standards and values. Psychological scholarship distinguishes between altruistic guilt (AG) and deontological guilt (DG). AG results from having caused harm to an innocent victim, either by acting or failing to act, whereas DG is caused by violating a moral principle. Although physicians may be expected to experience frequent feelings of guilt in their demanding and intensive work, it is surprising to find that this issue has not been explored in the professional literature on medical ethics. To that end, we conducted a qualitative study that included personal in-depth interviews with Sunni Muslim gynaecologists. These doctors provide underground infertility care and perform religiously forbidden treatments involving sex selection and gamete donation. They opened their hearts and spoke about the emotionally taxing pangs of conscience they suffer. Analysing their narratives led us to characterize their feelings of guilt as DG. We discuss the causes for their plight and the way they cope with it, compare DG to the concept of moral distress, and call for future research on clinicians' feelings of guilt and pangs of conscience.

2.
J Hosp Infect ; 126: 116-122, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35569577

RESUMEN

OBJECTIVE: Data on the transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) remain conflicting. Airborne transmission is still debated. However, hospital risk control requires better understanding of the different modes of transmission. This study aimed to evaluate the frequency of, and factors associated with, environmental air and surface contamination in the rooms of patients with coronavirus disease 2019 in the acute phase of the disease. METHODS: Sixty-five consecutive patients were included in this study. For each patient, seven room surfaces, air 1 m and 3 m from the patient's head, the inner surface of the patient's mask, and the outer surface of healthcare workers' (HCW) masks were sampled. Environmental contamination was assessed by quantitative reverse transcription polymerase chain reaction (RT-qPCR) for SARS-CoV-2 RNA on surfaces, air and masks. A viral isolation test was performed on Vero cells for samples with an RT-qPCR cycle threshold (Ct) ≤37. RESULTS: SARS-CoV-2 RNA was detected by RT-qPCR in 34%, 12%, 50% and 10% of surface, air, patient mask and HCW mask samples, respectively. Infectious virus was isolated in culture from two samples among the 85 positive samples with Ct ≤37. On multi-variate analysis, only a positive result for SARS-CoV-2 RT-qPCR for patients' face masks was found to be significantly associated with surface contamination (odds ratio 5.79, 95% confidence interval 1.31-25.67; P=0.025). CONCLUSION: This study found that surface contamination by SARS-CoV-2 was more common than air and mask contamination. However, viable virus was rare. The inner surface of a patient's mask could be used as a marker to identify those at higher risk of contamination.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Chlorocebus aethiops , Hospitales , Humanos , Habitaciones de Pacientes , ARN Viral , Células Vero
3.
BJOG ; 129(2): 267-272, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34486797

RESUMEN

OBJECTIVE: To examine the putative associations between breast implants and postpartum lactational mastitis. DESIGN: Observational retrospective study. SETTING: Digital database of Maccabi Healthcare Services, integrated health maintenance organisation in Israel. POPULATION: Breastfeeding mothers from 2003 to 2016 based on an initial health maintenance organisation data set of 28 383 singleton live births in Israel. METHODS: Multivariate analysis and propensity score matching were used to test the extent to which breast implants were associated with lactational mastitis during the 6-month postpartum period in breastfeeding mothers. Analyses for potential confounders were adjusted for socio-economic status, smoking and parity. MAIN OUTCOME MEASURE: Lactational mastitis among breastfeeding women with breast implants compared with women without breast implants. RESULTS: Mothers with breast implants (n = 6099) were significantly (P < 0.001) more likely to be diagnosed with postpartum mastitis (8.3%) than mothers with no breast implants(n = 22 284) (6.6%) at an odds ratio of 1.22 (95% CI 1.09-1.35) after adjusting for confounders. CONCLUSION: Breast augmentation is associated with an increased risk of postpartum lactational mastitis in the 6-month postpartum period. In light of these findings, it is important for health professionals to instruct women who have undergone breast augmentation on correct breastfeeding techniques, ways to avoid risk factors, and to be alert to signs permitting the early detection of lactational mastitis. TWEETABLE ABSTRACT: A study of over 28,000 breastfeeding women has shown that breast augmentation is associated with an increased risk of postpartum lactational mastitis in the six-month postpartum period.


Asunto(s)
Lactancia Materna , Implantes de Mama/efectos adversos , Mastitis/epidemiología , Adolescente , Adulto , Bases de Datos Factuales , Femenino , Humanos , Recién Nacido , Israel/epidemiología , Mastitis/etiología , Persona de Mediana Edad , Análisis Multivariante , Periodo Posparto , Embarazo , Puntaje de Propensión , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
4.
Blood Adv ; 5(16): 3053-3061, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34387648

RESUMEN

Patients diagnosed with B-cell non-Hodgkin lymphoma (B-NHL), particularly if recently treated with anti-CD20 antibodies, are at risk of severe COVID-19 disease. Because studies evaluating humoral response to COVID-19 vaccine in these patients are lacking, recommendations regarding vaccination strategy remain unclear. The humoral immune response to BNT162b2 messenger RNA (mRNA) COVID-19 vaccine was evaluated in patients with B-NHL who received 2 vaccine doses 21 days apart and compared with the response in healthy controls. Antibody titer, measured by the Elecsys Anti-SARS-CoV-2S assay, was evaluated 2 to 3 weeks after the second vaccine dose. Patients with B-NHL (n = 149), aggressive B-NHL (a-B-NHL; 47%), or indolent B-NHL (i-B-NHL; 53%) were evaluated. Twenty-eight (19%) were treatment naïve, 37% were actively treated with a rituximab/obinutuzumab (R/Obi)-based induction regimen or R/Obi maintenance, and 44% had last been treated with R/Obi >6 months before vaccination. A seropositive response was achieved in 89%, 7.3%, and 66.7%, respectively, with response rates of 49% in patients with B-NHL vs 98.5% in 65 healthy controls (P < .001). Multivariate analysis revealed that longer time since exposure to R/Obi and absolute lymphocyte count ≥0.9 × 103/µL predicted a positive serological response. Median time to achieve positive serology among anti-CD20 antibody-treated patients was longer in i-B-NHL vs a-B-NHL. The humoral response to BNT162b2 mRNA COVID-19 vaccine is impaired in patients with B-NHL who are undergoing R/Obi treatment. Longer time since exposure to R/Obi is associated with improved response rates to the COVID-19 vaccine. This study is registered at www.clinicaltrials.gov as #NCT04746092.


Asunto(s)
COVID-19 , Linfoma no Hodgkin , Linfocitos B , Vacuna BNT162 , Vacunas contra la COVID-19 , Humanos , Linfoma no Hodgkin/terapia , ARN Mensajero , SARS-CoV-2
5.
Comput Electron Agric ; 187: None, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34381288

RESUMEN

Collection of accurate and representative data from agricultural fields is required for efficient crop management. Since growers have limited available resources, there is a need for advanced methods to select representative points within a field in order to best satisfy sampling or sensing objectives. The main purpose of this work was to develop a data-driven method for selecting locations across an agricultural field given observations of some covariates at every point in the field. These chosen locations should be representative of the distribution of the covariates in the entire population and represent the spatial variability in the field. They can then be used to sample an unknown target feature whose sampling is expensive and cannot be realistically done at the population scale. An algorithm for determining these optimal sampling locations, namely the multifunctional matching (MFM) criterion, was based on matching of moments (functionals) between sample and population. The selected functionals in this study were standard deviation, mean, and Kendall's tau. An additional algorithm defined the minimal number of observations that could represent the population according to a desired level of accuracy. The MFM was applied to datasets from two agricultural plots: a vineyard and a peach orchard. The data from the plots included measured values of slope, topographic wetness index, normalized difference vegetation index, and apparent soil electrical conductivity. The MFM algorithm selected the number of sampling points according to a representation accuracy of 90% and determined the optimal location of these points. The algorithm was validated against values of vine or tree water status measured as crop water stress index (CWSI). Algorithm performance was then compared to two other sampling methods: the conditioned Latin hypercube sampling (cLHS) model and a uniform random sample with spatial constraints. Comparison among sampling methods was based on measures of similarity between the target variable population distribution and the distribution of the selected sample. MFM represented CWSI distribution better than the cLHS and the uniform random sampling, and the selected locations showed smaller deviations from the mean and standard deviation of the entire population. The MFM functioned better in the vineyard, where spatial variability was larger than in the orchard. In both plots, the spatial pattern of the selected samples captured the spatial variability of CWSI. MFM can be adjusted and applied using other moments/functionals and may be adopted by other disciplines, particularly in cases where small sample sizes are desired.

6.
Int J Tuberc Lung Dis ; 25(3): 199-205, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33688808

RESUMEN

OBJECTIVE: Interstitial lung diseases (ILDs) are associated with poor prognosis in the intensive care unit (ICU). We aimed to assess factors associated with hospital mortality in ILD patients admitted to the ICU and to investigate long-term outcome.MATERIAL AND METHODS: This was a retrospective study in a teaching hospital specialised in ILD management. Patients with ILD who were hospitalised in the ICU between 2000 and 2014 were included. Independent predictors of hospital mortality were identified using logistic regression.RESULTS: A total of 196 ILD patients were admitted to the ICU during the study period. Overall hospital mortality was 55%. Two years after ICU admission, 70 (36%) patients were still alive. Of the 196 patients, 108 (55%) required invasive mechanical ventilation, of whom 21 (20%) were discharged alive from hospital. Acute exacerbation of ILD and multi-organ failure were highly associated with hospital mortality (OR 5.4, 95% CI 1.9-15.5 and OR 12.6, 95% CI 4.9-32.5, respectively).CONCLUSION: Hospital mortality among ILD patients hospitalised in the ICU was high, but even where invasive mechanical ventilation was required, a substantial number of patients were discharged alive from hospital. Multi-organ failure could lead to major ethical concerns.


Asunto(s)
Unidades de Cuidados Intensivos , Enfermedades Pulmonares Intersticiales , Estudios de Seguimiento , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Enfermedades Pulmonares Intersticiales/terapia , Pronóstico , Respiración Artificial , Estudios Retrospectivos
7.
J Ovarian Res ; 13(1): 22, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32101156

RESUMEN

BACKGROUND: Fragile X premutation (Amplification of CGG number 55-200) is associated with increased risk for fragile X-Associated Premature Ovarian Insufficiency (FXPOI) in females and fragile X-associated tremor/ataxia syndrome (FXTAS) predominantly in males. Recently, it has been shown that CGG repeats trigger repeat associated non-AUG initiated translation (RAN) of a cryptic polyglycine-containing protein, FMRpolyG. This protein accumulates in ubiquitin-positive inclusions in neuronal brain cells of FXTAS patients and may lead to protein-mediated neurodegeneration. FMRpolyG inclusions were also found in ovary stromal cells of a FXPOI patient. The role of FMRpolyG expression has not been thoroughly examined in folliculogenesis related cells. The main goal of this study is to evaluate whether FMRpolyG accumulates in mural granulosa cells of FMR1 premutation carriers. Following FMRpolyG detection, we aim to examine premutation transfected COV434 as a suitable model used to identify RAN translation functions in FXPOI pathogenesis. RESULTS: FMRpolyG and ubiquitin immunostained mural granulosa cells from six FMR1 premutation carriers demonstrated FMRpolyG aggregates. However, co-localization of FMRpolyG and ubiquitin appeared to vary within the FMR1 premutation carriers' group as three exhibited partial ubiquitin and FMRpolyG double staining and three premutation carriers demonstrated FMRpolyG single staining. None of the granulosa cells from the five control women expressed FMRpolyG. Additionally, human ovarian granulosa tumor, COV434, were transfected with two plasmids; both expressing 99CGG repeats but only one enables FMRpolyG expression. Like in granulosa cells from FMR1 premutation carriers, FMRpolyG aggregates were found only in COV434 transfected with expended CGG repeats and the ability to express FMRpolyG. CONCLUSIONS: Corresponding with previous studies in FXTAS, we demonstrated accumulation of FMRpolyG in mural granulosa cells of FMR1 premutation carriers. We also suggest that following further investigation, the premutation transfected COV434 might be an appropriate model for RAN translation studies. Detecting FMRpolyG accumulation in folliculogenesis related cells supports previous observations and imply a possible common protein-mediated toxic mechanism for both FXPOI and FXTAS.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Células de la Granulosa/metabolismo , Adulto , Animales , Ataxia/genética , Ataxia/metabolismo , Modelos Animales de Enfermedad , Femenino , Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/metabolismo , Humanos , Ratones , Ratones Transgénicos , Mutación , Insuficiencia Ovárica Primaria/genética , Insuficiencia Ovárica Primaria/metabolismo , Transfección , Temblor/genética , Temblor/metabolismo
8.
J Assist Reprod Genet ; 37(4): 849-854, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32096109

RESUMEN

PURPOSE: While FMR1 premutation carriers (CGG 55-200) were shown to have reduced success with IVF treatment (lower oocyte yield), studies reporting on the association between the number of CGG repeats and patients' response to controlled ovarian hyperstimulation (COH) are inconsistent. In the present study, we aim to explore whether the number of CGG repeats in women with premutation in FMR1 gene, undergoing COH for IVF, correlates with COH variables and whether the number of AGG interruptions may function as a "protective factor" by improving the ovarian response to COH. METHODS: Retrospective study, in an academic IVF-PGD unit. Fifty-seven consecutive FMR1 premutation carriers who underwent 285 IVF treatment cycles were included. The numbers of CGG repeats and AGG interruptions were retrieved and correlated to the demographics and COH variables. RESULTS: There were no significant association between the numbers of CGG or the AGG interruptions and the number of oocyte retrieved or the peak estradiol levels. The lack of association was also observed when including all the IVF treatment cycles or only the first or last IVF treatment cycle. Moreover, no associations were found between the number of CGG repeats or AGG interruptions and other COH variables, i.e., duration of stimulation, the total dose of gonadotropin used, or the number of top-quality embryos. CONCLUSIONS: No associations were observed between the number of CGG repeats or AGG interruptions and any of the COH variables. Further studies are required to identify early biomarkers of POI to empower FMR1 premutation carriers with risk assessment tools to consider procedures such as fertility preservation.


Asunto(s)
Fertilidad/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Repeticiones de Trinucleótidos/genética , Adulto , Alelos , Femenino , Fertilización In Vitro , Síndrome del Cromosoma X Frágil/epidemiología , Síndrome del Cromosoma X Frágil/patología , Gonadotropinas/genética , Heterocigoto , Humanos , Ovario/crecimiento & desarrollo , Ovario/patología , Expansión de Repetición de Trinucleótido/genética
9.
J Intensive Care ; 7: 45, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31452899

RESUMEN

BACKGROUND: Extracorporeal carbon dioxide removal (ECCO2R) is a promising technique for the management of acute respiratory failure, but with a limited level of evidence to support its use outside clinical trials and/or data collection initiatives. We report a collaborative initiative in a large metropolis. METHODS: To assess on a structural basis the rate of utilization as well as efficacy and safety parameters of 2 ECCO2R devices in 10 intensive care units (ICU) during a 2-year period. RESULTS: Seventy patients were recruited in 10 voluntary and specifically trained centers. The median utilization rate was 0.19 patient/month/center (min 0.04; max 1.20). ECCO2R was started under invasive mechanical ventilation (IMV) in 59 patients and non-invasive ventilation in 11 patients. The Hemolung Respiratory Assist System (Alung) was used in 53 patients and the iLA Activve iLA kit (Xenios Novalung) in 17 patients. Main indications were ultraprotective ventilation for ARDS patients (n = 24), shortening the duration of IMV in COPD patients (n = 21), preventing intubation in COPD patients (n = 9), and controlling hypercapnia and dynamic hyperinflation in mechanically ventilated patients with severe acute asthma (n = 6). A reduction in median V T was observed in ARDS patients from 5.9 to 4.1 ml/kg (p <0.001). A reduction in PaCO2 values was observed in AE-COPD patients from 67.5 to 51 mmHg (p< 0.001). Median duration of ECCO2R was 5 days (IQR 3-8). Reasons for ECCO2R discontinuation were improvement (n = 33), ECCO2R-related complications (n = 18), limitation of life-sustaining therapies or measures decision (n = 10), and death (n = 9). Main adverse events were hemolysis (n = 21), bleeding (n = 17), and lung membrane clotting (n = 11), with different profiles between the devices. Thirty-five deaths occurred during the ICU stay, 3 of which being ECCO2R-related. CONCLUSIONS: Based on a registry, we report a low rate of ECCO2R device utilization, mainly in severe COPD and ARDS patients. Physiological efficacy was confirmed in these two populations. We confirmed safety concerns such as hemolysis, bleeding, and thrombosis, with different profiles between the devices. Such results could help to design future studies aiming to enhance safety, to demonstrate a still-lacking strong clinical benefit of ECCO2R, and to guide the choice between different devices. TRIAL REGISTRATION: ClinicalTrials.gov: Identifier: NCT02965079 retrospectively registered https://clinicaltrials.gov/ct2/show/NCT02965079.

10.
Rev Med Interne ; 40(4): 255-257, 2019 Apr.
Artículo en Francés | MEDLINE | ID: mdl-30616928

RESUMEN

INTRODUCTION: Acute muscle involvement is an infrequent complication of corticosteroids, characterized by muscle weakness and a rhabdomyolysis, rapidly regressive after withdrawal of corticosteroids. CASE REPORT: We report the case of a woman admitted in intensive care unit for acute severe asthma, treated with high doses of methylprednisolone. Serum CPK level raised with a peak at 28,160 UI/L (n<250 UI/L) at day 15, suggesting acute rhabdomyolysis with renal failure. CPK rapidly normalized when corticosteroids were discontinued. Other causes of rhabdomyolysis were ruled out. CONCLUSION: This necrosing myopathy under high doses of corticosteroids has been described in patients with severe acute asthma. The mechanism of the muscle damage results from a combination of corticosteroids toxicity, respiratory acidosis and mechanic ventilation.


Asunto(s)
Corticoesteroides/efectos adversos , Asma/tratamiento farmacológico , Rabdomiólisis/inducido químicamente , Enfermedad Aguda , Corticoesteroides/uso terapéutico , Asma/patología , Enfermedad Crítica , Femenino , Humanos , Unidades de Cuidados Intensivos , Persona de Mediana Edad , Rabdomiólisis/diagnóstico , Índice de Severidad de la Enfermedad
11.
Artículo en Inglés | MEDLINE | ID: mdl-28900539

RESUMEN

Biofilms are organised aggregates of bacteria that adhere to each other or surfaces. The matrix of extracellular polymeric substances that holds the cells together provides the mechanical stability of the biofilm. In this study, we have applied Brillouin microscopy, a technique that is capable of measuring mechanical properties of specimens on a micrometre scale based on the shift in frequency of light incident upon a sample due to thermal fluctuations, to investigate the micromechanical properties of an active, live Pseudomonas aeruginosa biofilm. Using this non-contact and label-free technique, we have extracted information about the internal stiffness of biofilms under continuous flow. No correlation with colony size was found when comparing the averages of Brillouin shifts of two-dimensional cross-sections of randomly selected colonies. However, when focusing on single colonies, we observed two distinct spatial patterns: in smaller colonies, stiffness increased towards their interior, indicating a more compact structure of the centre of the colony, whereas, larger (over 45 µm) colonies were found to have less stiff interiors.

12.
Transl Psychiatry ; 7(8): e1207, 2017 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-28809861

RESUMEN

Although there have been previous studies of deep-brain stimulation (DBS), we present, to our knowledge, the first example of high-frequency depressive severity measurement-based DBS treatment in particular and psychiatric treatment in general. Daily post-surgical e-mail prompts for a period of 6 months resulted in 93 administrations of a computerized adaptive test (CAT) of depression severity (CAT-Depression Inventory or CAT-DI) via the internet. There was an average of 3.37 weekly measurements with an average separation of 2.12 days. No additional incentive was provided to the patient for completing the adaptive tests. The patient is a 55-year-old female with six psychiatric hospitalizations for depression, two suicide attempts, marginal response to eight electroconvulsive therapy (ECT) treatments and 35 psychotropic medications. We report results after high-frequency stimulation of the superolateral branch of the medial forebrain bundle. The CAT-DI was used for daily assessments before, during and after (remotely in response to an e-mail prompt) the DBS procedure. Two follow-up Hamilton Depression Scales (HAM-Ds) were also collected. Response to treatment varied markedly, with a decrease from severe (>75) to mild (60), which is three times the size of the uncertainty level. Although the HAM-D scores decreased, they missed the more complete temporal pattern identified by CAT-DI daily monitoring. We demonstrated feasibility of daily depressive severity measurement at high levels of precision and compliance. Clinician ratings confirm the general pattern of treatment benefit, but mask the marked variability in mood and more marked periods of benefit and decline.


Asunto(s)
Estimulación Encefálica Profunda , Trastorno Depresivo Resistente al Tratamiento/diagnóstico , Trastorno Depresivo Resistente al Tratamiento/terapia , Femenino , Humanos , Haz Prosencefálico Medial/fisiopatología , Persona de Mediana Edad , Cooperación del Paciente , Escalas de Valoración Psiquiátrica , Índice de Severidad de la Enfermedad , Telemedicina , Resultado del Tratamiento
13.
J Laryngol Otol ; 131(9): 817-822, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28758602

RESUMEN

OBJECTIVE: This study aimed to investigate the prevalence of and risk factors for Eustachian tube dysfunction leading to middle-ear pathology in patients on chronic mechanical ventilation via tracheostomy tube. METHODS: A total of 40 patients on chronic ventilation were included in a prospective cohort study. Middle-ear status was determined by tympanometry. Tympanograms were categorised as types A, B or C; types B and C were defined as middle-ear pathology. RESULTS: In all, 57 ears of 40 patients were examined. Disease was found in at least 1 ear in 26 out of 40 patients. Middle-ear pathology was found in 25 out of 34 patients who were tube fed (via nasogastric tube or percutaneous endoscopic gastrostomy) vs 1 patient out of the 6 fed orally (p = 0.014), and in 23 out of 31 with conscious or cognitive impairment vs 3 out of 9 cognitively intact patients (p = 0.044). CONCLUSION: Middle-ear pathology is common in patients on chronic mechanical ventilation via tracheostomy tube. The highest prevalence was in those with impaired consciousness or cognition, and oral feeding appeared protective.


Asunto(s)
Enfermedades del Oído/epidemiología , Trompa Auditiva/fisiopatología , Respiración Artificial/efectos adversos , Pruebas de Impedancia Acústica , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades del Oído/fisiopatología , Oído Medio/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
14.
16.
Phys Rev E ; 95(3-1): 033113, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28415309

RESUMEN

Inspired by river networks and other structures formed by Laplacian growth, we use the Loewner equation to investigate the growth of a network of thin fingers in a diffusion field. We first review previous contributions to illustrate how this formalism reduces the network's expansion to three rules, which respectively govern the velocity, the direction, and the nucleation of its growing branches. This framework allows us to establish the mathematical equivalence between three formulations of the direction rule, namely geodesic growth, growth that maintains local symmetry, and growth that maximizes flux into tips for a given amount of growth. Surprisingly, we find that this growth rule may result in a network different from the static configuration that optimizes flux into tips.

17.
Anaesthesia ; 72(2): 156-171, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27900760

RESUMEN

A predicted difficult airway is sometimes considered a contra-indication to rapid sequence induction of general anaesthesia, even in an urgent case such as a category-1 caesarean section for fetal distress. However, formally assessing the risk is difficult because of the rarity and urgency of such cases. We have used decision analysis to quantify the time taken to establish anaesthesia, and probability of failure, of three possible anaesthetic methods, based on a systematic review of the literature. We considered rapid sequence induction of general anaesthesia with videolaryngoscopy, awake fibreoptic intubation and rapid spinal anaesthesia. Our results show a shorter mean (95% CI) time to induction of 100 (87-114) s using rapid sequence induction compared with 9 (7-11) min for awake fibreoptic intubation (p < 0.0001) and 6.3 (5.4-7.2) min for spinal anaesthesia (p < 0.0001). We calculate the risk of ultimate failed airway control after rapid sequence induction to be 21 (0-53) per 100,000 cases, and postulate that some mothers may accept such a risk in order to reduce potential fetal harm from an extended time interval until delivery. Although rapid sequence induction may not be the anaesthetic technique of choice for all cases in the circumstance of a category-1 caesarean section for fetal distress with a predicted difficult airway, we suggest that it is an acceptable option.


Asunto(s)
Anestesia Obstétrica/métodos , Cesárea/métodos , Técnicas de Apoyo para la Decisión , Intubación Intratraqueal/métodos , Femenino , Tecnología de Fibra Óptica , Humanos , Máscaras Laríngeas , Laringoscopía
18.
Oncogene ; 36(5): 628-638, 2017 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-27452524

RESUMEN

Chronic lymphocytic leukemia (CLL) is a malignant disease of small mature lymphocytes. Signals from the CLL microenvironment promote progression of the disease and induce drug resistance. This phenomenon is largely dependent on direct contact between the malignant B cells and stromal cells. CD84 belongs to the signaling lymphocyte activation molecule family of immunoreceptors, which self-associates, forming an orthogonal homophilic dimer. We therefore hypothesized that CD84 may bridge between CLL cells and their microenvironment, promoting cell survival. Our in vitro results show that CD84 expressed on CLL cells interact with CD84 expressed on cells in their microenvironment, inducing cell survival in both sides. Blocking CD84 in vitro and in vivo disrupt the interaction of CLL cells with their microenvironment, resulting in induced cell death. Thus, our findings suggest novel therapeutic strategies based on the blockade of this CD84-dependent survival pathway.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/biosíntesis , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microambiente Tumoral
19.
Int J Oral Maxillofac Surg ; 45(6): 721-5, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26811072

RESUMEN

The phosphoinositide 3-kinase (PIK3)/v-akt murine thymoma (AKT) oncogene pathway and the RAS/RAF pathway are involved in regulating the signalling of multiple biological processes, including apoptosis, metabolism, cell proliferation, and cell growth. Mutations in the genes within these pathways are frequently found in several tumours. The aim of this study was to investigate the frequency of mutations in the PIK3CA, BRAF, and KRAS genes in cases of malignant salivary gland tumours. Mutational analysis of the PIK3CA, KRAS, and BRAF genes was performed by direct sequencing of material from 21 patients with malignant salivary gland tumours who underwent surgery between 1992 and 2001. No mutations were found in the KRAS exon 2, BRAF exon 15, or PIK3CA exon 9 genes. However, an unpublished mutation of the PIK3CA gene in exon 20 (W1051 stop mutation) was found in one case of adenocarcinoma NOS. The impact of this mutation on the biological behaviour of the tumour has yet to be explored, however the patient with adenocarcinoma NOS harbouring this mutation has survived for over 20 years following surgery despite a high stage at presentation. Further studies with more homogeneous patient cohorts are needed to address whether this mutation reflects a different clinical presentation and may benefit from targeted treatment strategies.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I/genética , Mutación , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-raf/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Neoplasias de las Glándulas Salivales/genética , Neoplasias de las Glándulas Salivales/metabolismo , Adulto , Anciano , Animales , Análisis Mutacional de ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Phytopathology ; 106(3): 254-61, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26623996

RESUMEN

Clavibacter michiganensis subsp. michiganensis, the causal agent of bacterial canker and wilt of tomato, is considered to be one of the most important bacterial pathogens worldwide. In the year 2000 there was an increase in the number of infected greenhouses and in the severity of the disease in Israel. As part of the effort to cope with the disease, a comprehensive survey was conducted. Scouts recorded disease severity monthly in 681 production units. At the end of the season the scouts met with the growers and together recorded relevant details about the crop and cultural practices employed. The results suggested an absence of anisotropy pattern in the study region. Global Moran's I analysis showed that disease severity had significant spatial autocorrelation. The strongest spatial autocorrelation occurred within a 1,500 m neighborhood, which is comparable to the distance between production units maintained by one grower (Farm). Next, we tested three groups of variables including or excluding the Farm as a variable. When the Farm was included the explained variation increased in all the studied models. Overall, results of this study demonstrate that the most influential factor on bacterial canker severity was the Farm. This variable probably encompasses variation in experience, differences in agricultural practices between growers, and the quality of implementation of management practices.


Asunto(s)
Actinobacteria/fisiología , Ambiente Controlado , Enfermedades de las Plantas/microbiología , Solanum lycopersicum/microbiología , Israel , Factores de Riesgo
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