67 resultados para paroxysmal nocturnal hemoglobinuria


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Adaptations to new pollinators involve multiple floral traits, each requiring coordinated changes in multiple genes. Despite this genetic complexity, shifts in pollination syndromes have happened frequently during angiosperm evolution. Here we study the genetic basis of floral UV absorbance, a key trait for attracting nocturnal pollinators. In Petunia, mutations in a single gene, MYB-FL, explain two transitions in UV absorbance. A gain of UV absorbance in the transition from bee to moth pollination was determined by a cis-regulatory mutation, whereas a frameshift mutation caused subsequent loss of UV absorbance during the transition from moth to hummingbird pollination. The functional differences in MYB-FL provide insight into the process of speciation and clarify phylogenetic relationships between nascent species.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

UNLABELLED Obstructive sleep apnea (OSA) is a frequent syndrome characterized by intermittent hypoxemia and increased prevalence of arterial hypertension and cardiovascular morbidity. In OSA, the presence of patent foramen ovale (PFO) is associated with increased number of apneas and more severe oxygen desaturation. We hypothesized that PFO closure improves sleep-disordered breathing and, in turn, has favorable effects on vascular function and arterial blood pressure. In 40 consecutive patients with newly diagnosed OSA, we searched for PFO. After initial cardiovascular assessment, the 14 patients with PFO underwent initial device closure and the 26 without PFO served as control group. Conventional treatment for OSA was postponed for 3 months in both groups, and polysomnographic and cardiovascular examinations were repeated at the end of the follow-up period. PFO closure significantly improved the apnea-hypopnea index (ΔAHI -7.9±10.4 versus +4.7±13.1 events/h, P=0.0009, PFO closure versus control), the oxygen desaturation index (ΔODI -7.6±16.6 versus +7.6±17.0 events/h, P=0.01), and the number of patients with severe OSA decreased significantly after PFO closure (79% versus 21%, P=0.007). The following cardiovascular parameters improved significantly in the PFO closure group, although remained unchanged in controls: brachial artery flow-mediated vasodilation, carotid artery stiffness, nocturnal systolic and diastolic blood pressure (-7 mm Hg, P=0.009 and -3 mm Hg, P=0.04, respectively), blood pressure dipping, and left ventricular diastolic function. In conclusion, PFO closure in OSA patients improves sleep-disordered breathing and nocturnal oxygenation. This translates into an improvement of endothelial function and vascular stiffening, a decrease of nighttime blood pressure, restoration of the dipping pattern, and improvement of left ventricular diastolic function. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01780207.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background Chronic mountain sickness (CMS) is often associated with vascular dysfunction, but the underlying mechanism is unknown. Sleep disordered breathing (SDB) frequently occurs at high altitude. At low altitude SDB causes vascular dysfunction. Moreover, in SDB, transient elevations of right-sided cardiac pressure may cause right-to-left shunting in the presence of a patent foramen ovale (PFO) and, in turn, further aggravate hypoxemia and pulmonary hypertension. We speculated that compared to healthy high-altitude dwellers, in patients with CMS, SDB and nocturnal hypoxemia are more pronounced and related to vascular dysfunction. Methods We performed overnight sleep recordings, and measured systemic and pulmonary-artery pressure in 23 patients with CMS (mean±SD age 52.8±9.8 y) and 12 healthy controls (47.8±7.8 y) at 3600 m. In a subgroup of 15 subjects with SDB, we searched for PFO with transesophagal echocardiography. Results The major new findings were that in CMS patients, a) SDB and nocturnal hypoxemia was more severe (P<0.01) than in controls (apnea/hypopnea index, AHI, 38.9±25.5 vs. 14.3±7.8[nb/h]; SaO2, 80.2±3.6 vs. 86.8±1.7[%], CMS vs. controls), and b) AHI was directly correlated with systemic blood pressure (r=0.5216, P=0.001) and pulmonary-artery pressure (r=0.4497, P=0.024). PFO was associated with more severe SDB (AHI 48.8±24.7 vs. 14.8±7.3[nb/h], P=0.013, PFO vs. no PFO) and hypoxemia. Conclusion SDB and nocturnal hypoxemia are more severe in CMS patients than in controls and are associated with systemic and pulmonary vascular dysfunction. The presence of a PFO appeared to further aggravate SDB. Closure of PFO may improve SDB, hypoxemia and vascular dysfunction in CMS patients. Clinical Trials Gov Registration NCT01182792.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

OBJECTIVES To assess 12-month changes in nutritional status and quality of life (QoL) in systemic sclerosis (SSc) patients requiring home parenteral nutrition (HPN). METHOD We conducted a retrospective, single-centre database analysis of SSc patients regarding a 12-month period of HPN at an interdisciplinary University Unit/team for nutrition and rheumatic diseases. Nutritional status was analysed by nutritional risk screening (NRS) and body mass index (BMI). QoL was evaluated using Short-Form Health Survey (SF-36) questionnaires. RESULTS Between 2008 and 2013, daily nocturnal HPN was initiated in five consecutive SSc patients (four females and one male, mean age 62.2 years) suffering severe malnutrition due to gastrointestinal tract (GIT) involvement. After 12 months of HPN, the mean NRS score decreased from 4.4 (range 4-5) to 1.4 (range 1-2), the mean BMI increased from 19.1 (range 17.4-20.3) to 21.0 kg/m(2) (range 18.3-23.4). QoL improved in all patients, reflected by the summary of physical components with 33.92 points before vs. 67.72 points after 12 months of HPN, and the summary of mental components with 49.66 points before vs. 89.27 points after 12 months of HPN. Two patients suffered one catheter-related infection each with subsequent surgical removal and reinsertion. CONCLUSIONS HPN is a feasible method for improving anthropometric parameters and QoL in SSc patients severely affected by GIT dysfunction. We recommend HPN in malnourished, catabolic SSc patients unable to otherwise maintain or improve their nutritional status.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND Traditional approaches for nighttime glycemic control in glycogen storage disease type I (GSDI) include continuous tube feeding, or ingestion of uncooked corn starch (CS) at bedtime. A modified corn starch (MCS) has been shown to prolong euglycemia in some patients. The aim of this study was to evaluate whether stable nighttime glucose control can be achieved with other types of slowly digested carbohydrates in adult GSDI patients. METHODS In this cross-over study, nocturnal glucose control and fasting times were assessed with three different nocturnal nutrition regimens in five patients, using continuous glucose monitoring (CGMS) in an outpatient everyday life setting. For each patient, continuous glucose profiles were measured after ingestion of (1) CS, (2) MCS or (3) a pasta meal at bedtime, during 5 to 6 consecutive nights for each regimen. RESULTS Stable nocturnal glucose control was achieved for all patients with a pasta meal, with a mean duration of glycemia >3.5 mmol/l of 7.6 h (range 5.7-10.8), and >4 mmol/l of 7 h (5.2-9.2), similar to CS and MCS. Fasting glucose before breakfast on workdays (after 7.1 ± 0.8 h) was not significantly different between the three interventions (CS 4.1 ± 0.5 mmol/l, MCS 4.6 ± 0.7 mmol/l, pasta 4.3 ± 0.9 mmol/l). During prolonged fasting on weekends, longer duration of normoglycemia was achieved with CS or MCS than with pasta. CONCLUSION Consumption of cooked pasta is a suitable and more palatable alternative to uncooked corn starch to achieve nighttime glucose control in adult patients with GSDI.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

PURPOSE Paroxysmal atrial fibrillation (PAF) often remains undiagnosed. Long-term surface ECG is used for screening, but has limitations. Esophageal ECG (eECG) allows recording high quality atrial signals, which were used to identify markers for PAF. METHODS In 50 patients (25 patients with PAF; 25 controls) an eECG and surface ECG was recorded simultaneously. Partially A-V blocked atrial runs (PBARs) were quantified, atrial signal duration in eECG was measured. RESULTS eECG revealed 1.8‰ of atrial premature beats in patients with known PAF to be PBARs with a median duration of 853ms (interquartile range (IQR) 813-1836ms) and a median atrial cycle length of 366ms (IQR 282-432ms). Even during a short recording duration of 2.1h (IQR 1.2-17.2h), PBARs occurred in 20% of PAF patients but not in controls (p=0.05). Left atrial signal duration was predictive for PAF (72% sensitivity, 80% specificity). CONCLUSIONS eECG reveals partially blocked atrial runs and prolonged left atrial signal duration - two novel surrogate markers for PAF.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The syndrome known as nocturnal frontal lobe epilepsy is recognized worldwide and has been studied in a wide range of clinical and scientific settings (epilepsy, sleep medicine, neurosurgery, pediatric neurology, epidemiology, genetics). Though uncommon, it is of considerable interest to practicing neurologists because of complexity in differential diagnosis from more common, benign sleep disorders such as parasomnias, or other disorders like psychogenic nonepileptic seizures. Moreover, misdiagnosis can have substantial adverse consequences on patients' lives. At present, there is no consensus definition of this disorder and disagreement persists about its core electroclinical features and the spectrum of etiologies involved. To improve the definition of the disorder and establish diagnostic criteria with levels of certainty, a consensus conference using formal recommended methodology was held in Bologna in September 2014. It was recommended that the name be changed to sleep-related hypermotor epilepsy (SHE), reflecting evidence that the attacks are associated with sleep rather than time of day, the seizures may arise from extrafrontal sites, and the motor aspects of the seizures are characteristic. The etiology may be genetic or due to structural pathology, but in most cases remains unknown. Diagnostic criteria were developed with 3 levels of certainty: witnessed (possible) SHE, video-documented (clinical) SHE, and video-EEG-documented (confirmed) SHE. The main research gaps involve epidemiology, pathophysiology, treatment, and prognosis.