Increased noradrenergic activity in prefrontal cortex slices of an animal model for attention-deficit hyperactivity disorder--the spontaneously hypertensive rat

Spontaneously hypertensive rats (SHR) are used as a model for attention-deficit/hyperactivity disorder (ADHD) since SHR are hyperactive and they show defective sustained attention in behavioral tasks. Using an in vitro superfusion technique we showed that norepinephrine (NE) release from prefrontal cortex slices of SHR was not different from that of their Wistar-Kyoto (WKY) control rats when stimulated either electrically or by exposure to buffer containing 25 mM K(+). The monoamine vesicle transporter is, therefore, unlikely to be responsible for the deficiency in DA observed in SHR, since, in contrast to DA, vesicle stores of NE do not appear to be depleted in SHR. In addition, alpha(2)-adrenoceptor mediated inhibition of NE release was reduced in SHR, suggesting that autoreceptor function was deficient in prefrontal cortex of SHR. So, while DA neurotransmission appears to be down-regulated in SHR, the NE system appears to be under less inhibitory control than in WKY suggesting hypodopaminergic and hypernoradrenergic activity in prefrontal cortex of SHR. These findings are consistent with the hypothesis that the behavioral disturbances of ADHD are the result of an imbalance between NE and DA systems in the prefrontal cortex, with inhibitory DA activity being decreased and NE activity increased relative to controls.     

Septic paradoxical embolus through a patent foramen ovale after pacemaker implantation

A case of a septic paradoxic embolus due to an infected pacemaker lead associated with a patent foramen ovale (PFO) is described. Treatment consisted of immediate intracardiac embolectomy, pericardial patch closure of the PFO, total removal of the infected pacemaker lead and generator, and placement of a new permanent epicardial lead pacemaker system.     

Breathe easy: 5 steps to better breathing with your metered-dose inhaler (MDI)

Proper use of the metered-dose inhaler (MDI) is essential for medications to prevent and treat acute asthma exacerbations. This training video teaches children and clinicians correct technique for MDI use.     

The use of hemodynamics to predict mortality in patients undergoing primary PCI for ST-elevation myocardial infarction

Introduction: Challenges remain in predicting mortality and severe myocardial dysfunction in patients undergoing primary percutaneous coronary intervention (PPCI) for ST elevation myocardial infarction (STEMI).

Areas covered: Cardiogenic shock is associated with a high mortality rate. Less well characterized are patients who are not in cardiogenic shock but will die from pump failure as a result of a STEMI. There is a long history of using hemodynamics to risk stratify patients with acute MI with the Killip class being shown to provide prognostic information in the prereperfusion, thrombolytic and PPCI eras. Recent studies have identified low systolic blood pressure (SBP), elevated heart rate, elevated left ventricular end diastolic pressure (LVEDP), and low SBP/LVEDP ratio as hemodynamic parameters associated with early mortality in patients undergoing PPCI. Although infrequently used, prognostic information can be obtained from right heart catheterization in the setting of STEMI with the best-studied parameters being cardiac power, pulmonary capillary wedge pressure (PCWP), cardiac output, right atrial pressure/PCWP ratio, and pulmonary artery pulsatility index.

Expert commentary: Hemodynamic parameters measured at the time of PPCI provide important prognostic information. Whether hemodynamics can be used to determine which patients benefit from early initiation of mechanical support remains to be determined.     

Clinical outcomes in patients with native valve infective endocarditis and diabetes mellitus

BACKGROUNDThere is a lack of data on the clinical outcomes in patients with native valve infective endocarditis (NVIE) and diabetes mellitus (DM).AIMTo investigate (1) trends in the prevalence of DM among patients with NVIE; and (2) the impact of DM on NVIE outcomes. METHODSWe identified 76385 with NVIE from the 2004 to 2014 National Inpatient Sample, of which 22284 (28%) had DM. We assessed trends in DM from 2004 to 2014 using the Cochrane Armitage test. We compared baseline comorbidities, microorganisms, and in-patients procedures between those with vs without DM. Propensity match analysis and multivariate logistic regression were used to investigate study outcomes in in-hospital mortality, stroke, acute heart failure, cardiogenic shock, septic shock, and atrioventricular block.RESULTSCrude rates of DM increased from in 22% in 2004 to 30% in 2014. There were significant differences in demographics, comorbidities and NVIE risk factors between the two groups. Staphylococcus aureus was the most common organism identified with higher rates in patients with DM (33.1% vs 35.6%; P < 0.0001). After propensity matching, in-hospital mortality (11.1% vs 11.9%; P < 0.0001), stroke (2.3% vs 3.0%; P < 0.0001), acute heart failure (4.6% vs 6.5%; P = 0.001), cardiogenic shock (1.5% vs 1.9%; P < 0.0001), septic shock (7.2% vs 9.6%; P < 0.0001), and atrioventricular block (1.5% vs 2.4%; P < 0.0001), were significantly higher in patients with DM. Independent predictors of mortality in NVIE patients with DM include hemodialysis, congestive heart failure, atrial fibrillation, staphylococcus aureus, and older age.CONCLUSIONThere is an increasing prevalence of DM in NVIE and it is associated with poorer outcomes. Further studies are crucial to identify the clinical, and sociodemographic contributors to this trend and develop strategies to mitigate its attendant risk.     

Characterization of 10 polymorphic microsatellite markers for the purple martin, Progne subis

The purple martin is a large North American swallow that suffered a severe population crash in the 20th century due to nesting competition from invasive species. We screened an enriched DNA library for microsatellites from purple martins (Progne subis subis). Ten loci consistently amplified and were polymorphic with an allele range of 2–19 and observed heterozygosity ranged from 0.31 to 0.93. Two loci are sex-linked, and two additional loci failed to meet Hardy–Weinberg expectations likely due to the presence of null alleles. These polymorphic microsatellite loci can be used for studies of genetic diversity, population structure, and relatedness, all of which have been suggested to determine the impact of substantial regional declines in population density.     

Radiotherapy for carcinoma in situ of the true vocal cords

PURPOSE: To report long-term rates of tumor control after radiotherapy (RT) for carcinoma in situ (CIS) of the true vocal cords (TVC). A comprehensive literature review was performed, and outcomes with other modalities of treatment for CIS of the TVC were compared. METHODS AND MATERIALS: Thirty patients with CIS of the TVC were treated between July 1967 and May 1998 with curative intent using megavoltage RT. Most patients (28 of 30) were treated with cobalt-60 through small (usually 5 x 5 cm) fields. Median RT dose was 56.25 Gy (range, 56.25-75 Gy; mean dose, 59.15 Gy) at 2.25 Gy per fraction. One patient was treated for a synchronous head and neck primary malignancy with large fields to a total dose of 75 Gy at 1.8 Gy per fraction. Approximately two thirds of the patients (19 of 30) were referred for RT because of recurrence after at least one stripping procedure. RESULTS: With a mean follow-up of 7.1 years (range, 2-17 years), the 5-year rates of local control, local control with larynx preservation, and ultimate local control (including salvage surgery) were the following: 88%, 88%, and 100%, respectively. Invasive squamous cell carcinoma developed in three (10%) of the patients. Time to failure was 14 months, 34 months, and 48 months, respectively. All three patients were surgically salvaged with a total laryngectomy. Cause-specific survival at 5 years was 100%. There were no late complications. CONCLUSIONS: RT to approximately 60 Gy at 2.25 Gy per fraction using small (5 x 5 cm) fields produces excellent results with CIS of the TVC.