Shifting food web structure during dam removal-Disturbance and recovery during a major restoration action.

We measured food availability and diet composition of juvenile salmonids over multiple years and seasons before and during the world's largest dam removal on the Elwha River, Washington State. We conducted these measurements over three sediment-impacted sections (the estuary and two sections of the river downstream of each dam) and compared these to data collected from mainstem tributaries not directly affected by the massive amount of sediment released from the reservoirs. We found that sediment impacts from dam removal significantly reduced invertebrate prey availability, but juvenile salmon adjusted their foraging so that the amount of energy in diets was similar before and during dam removal. This general pattern was seen in both river and estuary habitats, although the mechanisms driving the change and the response differed between habitats. In the estuary, the dietary shifts were related to changes in invertebrate assemblages following a hydrological transition from brackish to freshwater caused by sediment deposition at the river's mouth. The loss of brackish invertebrate species caused fish to increase piscivory and rely on new prey sources such as plankton. In the river, energy provided to fish by Ephemeroptera, Plecoptera, and Trichoptera taxa before dam removal was replaced first by terrestrial invertebrates, and then by sediment-tolerant taxa such as Chironomidae. The results of our study are consistent with many others that have shown sharp declines in invertebrate density during dam removal. Our study further shows how those changes can move through the food web and affect fish diet composition, selectivity, and energy availability. As we move further along the dam removal response trajectory, we hypothesize that food web complexity will continue to increase as annual sediment load now approaches natural background levels, anadromous fish have recolonized the majority of the watershed between and above the former dams, and revegetation and microhabitats continue to develop in the estuary.

Health care disparities in the acute management of venous thromboembolism based on insurance status in the U.S.

Acute venous thromboembolism (VTE) is common, costly, and potentially lethal. Therapeutic anticoagulation requires timely, closely monitored medical follow-up. If ineffective, clinical outcomes worsen and resource utilization increases. This risk may be magnified in uninsured patients. This study examined VTE care in hospital patients and investigated differences based on insurance status. We performed a retrospective chart review on medical VTE patients at an academic teaching hospital between December 1, 2007 and April 30, 2009. We reviewed medical records for demographics, insurance, admission status, length of stay (LOS), and 30-day Emergency Department (ED) recidivism and hospital readmission. Measured outcomes were analyzed based on payer source. We identified 234 medical VTE patients; 67 patients were uninsured (28.6%). 106 patients (45.3%) presented with deep vein thrombosis only. Most VTE patients were admitted to the hospital (171; 73.1%), including all 128 pulmonary embolism patients. Admitted uninsured patients averaged a LOS of 5.5 versus 3.7 days for insured (P = 0.03), with ED recidivism rates of 26.1 versus 11.3%, respectively (P = 0.02). Average cost for all VTE care in uninsured patients was $12,297 versus $7,758 for insured patients (P = 0.04). This study identified disparities in medical care and resource utilization for medical VTE patients based on insurance. Uninsured VTE patients were hospitalized nearly two additional days and were more than two times as likely to return to the ED within 30 days compared to insured patients. Additional research is needed to explain these disparities, and to explore system improvements for the uninsured VTE patient.

Familial clustering of ruptured intracranial aneurysms in autosomal dominant polycystic kidney disease.

Ruptured intracranial aneurysm (RICA) is a life-threatening complication of autosomal dominant polycystic kidney disease (ADPKD). A family history of RICA may be a risk factor for RICA. Six hundred eight adult members of 199 ADPKD families were interviewed, and family pedigrees were constructed. Individuals were classified as having definite, probable, or possible RICAs from evidence and history obtained in interviews. Central nervous system (CNS) events not consistent with RICA were classified as other CNS events. Seventy-seven CNS events occurred in 906 subjects with ADPKD (8.5%) versus 13 events in 823 subjects without ADPKD (1.6%; P < 0.0001). No event in subjects without ADPKD was consistent with an RICA. Twenty-seven other (non-RICA) CNS events occurred in subjects with ADPKD (3%) versus 13 events in subjects without ADPKD (1.6%; P = 0.05). The frequency of RICA was increased in subjects with ADPKD: 21 definite RICAs in subjects with ADPKD (2%) versus none in subjects without ADPKD (P < 0.001); 28 definite and probable RICAs in subjects with ADPKD (3%) versus none in subjects without ADPKD (P < 0.001); and 50 definite, probable, and possible RICAs in subjects with ADPKD (5.5%) versus none in subjects without ADPKD (P < 0.001). The null hypothesis that RICAs are randomly distributed among subjects with ADPKD was tested for definite RICAs (n = 21), definite and probable RICAs (n = 28), and definite, probable, and possible RICAs (n = 50). In the three categories, the null hypothesis was rejected at P less than 0.05, P less than 0.05, and P less than 0.005, respectively. Vascular CNS events occurred more frequently in ADPKD than non-ADPKD family members, and clustering of RICAs occurred in families with ADPKD.

Mental retardation and sentences for murder: comparison of two recent court cases.

Several states and the United States have laws that exempt persons who have mental retardation from the death penalty and other severe sentences. Two recent murder cases in Indiana, which has such a law, illustrate some of the problems in applying it. The characteristics of the two defendants were quite similar, but one defendant was found to have mental retardation and was exempted from the death penalty and the other was not. The disparity was attributed to differences in the assessment of adaptive behavior and to general stereotypes of people who have mental retardation. Equal application of sentencing limitation laws requires greater involvement of professionals with specialized training and experience in mental retardation.

Quality improvement in an integrated urban healthcare system: a necessary journey.

Public hospitals and clinics in the United States provide health care for the needs of large numbers of people who are medically indigent, homeless, chronically mentally ill, and suffer medical and social disorders associated with poverty. These "safety-net" healthcare providers traditionally struggle with barriers to providing high-quality, patient-sensitive care, including decaying physical facilities, burdensome bureaucracies, underfunded capital equipment and construction programs, and complex, politically driven budgets and governance. However, these same institutions now must compete for their own Medicaid and Medicare clientele because the private sector is marketing to those patients. They also must continue to provide increasing services to growing numbers of uninsured patients. To accomplish this, these institutions must reinvent themselves as patient-focused, high-quality, cost-effective healthcare providers. The Denver Health system is the public safety-net provider for the city and county of Denver. This large public institution has instituted a multifaceted performance-improvement program. The program includes training employees for patient-focused service, implementing continuous quality-improvement practices, instituting clinical pathways, revising the preexisting ambulatory quality-management program, reengineering key aspects of ambulatory clinic services, and redesigning the hospital-based patient-care services. Major successes have been achieved in some initiatives, but not in all. Many key "lessons learned" may guide others.

Report of the AAN Task Force on access to health care: the effect of no personal health insurance on health care for people with neurologic disorders. Task Force on Access to Health Care of the American Academy of Neurology.

Access to medical care is limited for people with no health insurance. In the United States, an estimated 31 to 41 million people under age 65 have no health insurance. Among the uninsured, an estimated 340,000 new cases of neurologic disorders occur annually. The Task Force on Access to Health Care of the Academy analyzed data from four nationwide health surveys to describe the national population of people with neurologic disorders (PWND) by insurance status and to examine access to care, utilization of services, and expenses for health care of PWND. Health insurance status significantly affected access to and utilization of health care services. Compared with insured PWND, the uninsured less often had a usual source of medical care, saw a particular doctor, or visited a neurologist. The uninsured had fewer doctor's office visits and fewer hospital admissions than privately insured PWND. In the doctor's office they got fewer tests, fewer referrals for therapies, but more medications. In the hospital they received more diagnostic and therapeutic procedures overall, but those with cerebrovascular disease received fewer angiograms and endarterectomies. National health care reform may improve access to care for PWND if they are equitably included in the new systems. However, neurologists should assertively advocate for the needs of PWND to have adequate insurance and appropriate access to neurologic consultations, neurologic tests, and treatments.

Seizures.

Alcohol-related seizures have been recognized since the time of Hippocrates. Most such seizures are related to acute abstinence from chronic, high doses of alcohol use. Increasing use of illicit drugs, especially cocaine, has dramatically increased the incidence of acute drug-toxicity-related seizures. In cases of alcohol- or drug-related seizures, occult structural and infectious causes must be ruled out. Treatment usually focuses on management of the alcohol or drug abuse. Rarely are anticonvulsants indicated.

Cytochrome oxidase in the human visual cortex: distribution in the developing and the adult brain.

Cytochrome-oxidase (CO) histochemistry has revealed important functional subdivisions, modules, and processing streams in the macaque visual cortex. The present study is aimed at analyzing the development and characteristics of CO patterns in the human visual cortex by means of histochemistry and immunohistochemistry. At 26 weeks of gestation, both the ventricular and subventricular zones had low levels of CO, while the cortical plate had moderate levels of CO. At birth, supragranular CO-rich zones (puffs) were not clearly organized, indicating that the development of puffs in the neonatal striate cortex lags behind that of the macaque monkey, whose puffs appear weeks before birth. Puffs were more clearly discernible in human cortex at postnatal day 24, and became well organized by the fourth postnatal month. Layer IVc alpha in the neonate exhibited a higher level of activity and amount of CO than the central portion of IVc beta, which contained a dense aggregate of small neurons. The base of IVc beta, however, was often as CO reactive as IVc alpha. In contrast, the majority of specimens available to us from the fourth postnatal month and from adults with no known neurological diseases had significantly greater CO reactivity in layer IVc beta than in IVc alpha. Layer VI was moderately reactive for CO throughout development. In V2, stripes with globular zones of high CO activity were sporadically present at birth, suggesting that their development may parallel or precede that of puffs in V1. These stripes with CO-rich globular zones became more prominent in the adult and radiated orthogonally from the V1/V2 border. They were not, however, clearly organized into alternating thick and thin stripes as they are in the squirrel monkey. Visual cortical areas beyond V2 exhibited high CO activity mainly in layers III and IV and moderate levels in VI, suggesting that sites associated with cortico-cortical pathways may be metabolically most active.

Intracranial aneurysms in autosomal dominant polycystic kidney disease.

BACKGROUND AND METHODS: Intracranial aneurysms are a feature of autosomal dominant polycystic kidney disease, but their prevalence is uncertain. We studied 92 subjects with autosomal dominant polycystic kidney disease who had no symptoms or signs of any neurologic disorder. To determine the prevalence of intracranial aneurysms, we performed high-resolution computed tomography (CT) in 60 subjects, four-vessel cerebral angiography in 21, and both procedures in 11. RESULTS: Four of the 88 subjects in whom the radiologic studies were successfully completed had intracranial aneurysms (4 percent; 95 percent confidence interval, 0.1 to 9 percent), as compared with the prevalence of 1 percent reported for an angiographic study of the general population. Three of the four subjects had multiple aneurysms. Seven subjects for whom the results of CT studies were suspicious underwent cerebral angiography: two had aneurysms, and five had normal vascular structures that accounted for the suspicious results of tomography. Four subjects who had normal CT imaging studies also had normal angiographic examinations. Eight of the 32 subjects who underwent angiography (25 percent) had transient complications, as compared with 22 of 220 control subjects (10 percent) who did not have polycystic kidney disease (P less than 0.05). We could not identify any risk factor in these subjects that was related to the occurrence of aneurysm. CONCLUSIONS: Asymptomatic intracranial aneurysms appear to be more frequent in people with polycystic kidney disease than in the general population, although our 95 percent confidence interval includes the possibility of no difference. Because cerebral angiography is associated with increased morbidity in people with polycystic kidney disease, we recommend high-resolution CT as a screening test.

Grand mal seizures temporally related to cocaine use: clinical and diagnostic features.

STUDY OBJECTIVES: To determine the appropriate diagnostic workup of the emergency department patient with an uncomplicated cocaine-related grand mal seizure. DESIGN SETTING: Retrospective analysis. A city and county ED with 45,000 selected visits per year. TYPE OF PARTICIPANTS: Thirty-seven patients with acute grand mal seizure after cocaine exposure were studied. All had historical or laboratory evidence of cocaine use and no history of prior seizure disorder. INTERVENTIONS: The diagnostic workup varied among patients. Most received computed head tomography (35), whereas fewer received-ECG (18), EEG (16), and lumbar puncture (six). MEASUREMENTS AND MAIN RESULTS: Thirty-three patients with an uncomplicated cocaine-related seizure had an unremarkable series of diagnostic tests. The four patients with remarkable neurologic manifestations were compared with the remainder of patients who were without neurologic abnormalities. Comparison of groups by route of cocaine intake revealed no significant difference in the time interval to seizure (P = .761). CONCLUSION: Diagnostic workup probably is not indicated for the patient experiencing a cocaine-related generalized seizure who will recover promptly and have a normal postictal examination.

The sudden unexplained death syndrome in epilepsy: demographic, clinical, and postmortem features.

Sudden unexplained death syndrome (SUDS) accounts for about 10% of deaths in patients with epilepsy. It is associated with subtherapeutic postmortem serum antiepileptic drug (AED) levels but no anatomic cause of death on autopsy. The mechanisms of death are not known. We investigated 44 cases of SUDS for details of seizure history, treatment, medical and psychological history, events at the time of death, and postmortem findings. Cases of status epilepticus, drowning or other identifiable causes of death were excluded. Two groups emerged: five children with uncontrolled seizures receiving multiple AEDs and good compliance with medications, and 39 adults with less frequent seizures, often receiving monotherapy, but noncompliant with medications. Four children (80%) but only one adult (3%) had fully therapeutic postmortem AED levels. Sixty-three percent of adults recently had experienced an unusually stressful life event. Investigation of the circumstances at the time of death suggested two possible modes of death: (a) a seizure with an immediately fatal arrhythmia, or, (b) a seizure, recovery, then delayed secondary respiratory arrest or arrhythmia. Even though the mechanisms of death are unknown, the risk of SUDS may be reduced by encouraging patients to be compliant with medications, especially in times of unusual life stress.

A PAF receptor antagonist, BN 52021, attenuates thromboxane release and improves survival in lethal canine endotoxemia.

Platelet-activating (PAF) is a putative mediator in endotoxemia and sepsis. Administration of a PAF receptor antagonist prior to endotoxin improves survival in rats and attenuates the hypotension of endotoxemia. Both PAF and endotoxin stimulate eicosanoid production. We hypothesized that a PAF receptor antagonist, BN 52021, would alter the hemodynamic events, improve the survival and attenuate the eicosanoid release associated with endotoxemia in a resuscitated, but lethal, canine model. Male dogs were randomzied to two groups (n = 10 each). Group I received only E. coli endotoxin, 1 mg/kg IV, at time 0, while group II received BN 52021, 5 mg/kg IV, 30 min before and again 240 min after endotoxin treatment. During the 4-h study period, hemodynamics were measured and blood samples were taken at 0, 2, 60, 120, and 240 min. Survival was determined at 24, 48, and 72 h. All group I animals died before 24 h; all group II lived longer than 72 h (P less than 0.05). In group I, plasma TXB2 values increased from a baseline value of 0.26 +/- .04 ng/ml to 4.38 +/- 1.56 ng/ml at 120 min and then decreased to 2.64 +/- .96 ng/ml by 240 min. For group II, respective plasma TXB2 values were 0.35 +/- 0.13 ng/ml at baseline, 0.58 +/- 0.14 ng/ml at 120 min, and 0.39 +/- .09 ng/ml at 240 min. At the 120-min and 240-min time points, the groups differed at P less than 0.05. Heart rate tended to be less in group II, but MAP was unaffected. In group I, pH values were more acidotic than those observed in group II.

Access to health care. One neurologist's perspective.

Millions of residents of the United States have difficulty obtaining health care. Barriers impeding access to care include poverty, physical unavailability of health care services, absence of health insurance, and physicians unwilling to care for uninsured patients. Many patients do not successfully use health services because of educational, cultural, and language barriers. A major access barrier is lack of health insurance. Over 30 million people in the United States have none, the so-called medically indigent. Among them are over 3 million people with neurologic disorders. They have additional barriers to overcome because often they cannot work, cannot drive, have difficulty using public transportation, and have major cognitive and communication impairments. Medical and governmental bodies are debating solutions to the health care access crisis. Physicians should actively participate in this national debate. Neurologists should address the special needs of patients with neurological disorders.

Access to health care in the United States: barriers for neurologic patients, challenges for neurologic physicians.

Approximately 34 million people in the United States have no health insurance. Up to 80 million people have insurance inadequate to provide care for severe or long-term illness (the underinsured). In 1986, an estimated 1 million persons in the US could not obtain needed health care for financial reasons, and another 18.8 million had difficulty obtaining care. There probably are 3.2 million people with neurologic disorders among the 34 million uninsured, and more among the underinsured. Those patients probably have difficulty obtaining health care, including neurologic consultations, laboratory tests, and radiologic procedures. Congress and many state legislatures are considering various proposals to address the problems of the un- and underinsured. Several national medical professional societies have developed programs to improve access to care for their patients. The American Academy of Neurology Task Force on Access to Health Care is studying access to care for neurologic patients and will recommend a course of action to the Academy. The Task Force welcomes suggestions concerning appropriate steps to improve access to health care for patients with neurologic disorders.

Platelet activating factor receptor antagonist improves survival and attenuates eicosanoid release in severe endotoxemia.

Exogenous platelet activating factor (PAF) causes hypotension, plasma extravasation, metabolic acidosis, and death. These effects are similar to those of endotoxin as well as the eicosanoids. A specific PAF receptor antagonist, BN52021, was used to determine its effects on the hemodynamic events, the eicosanoid production, and on survival in severe rat endotoxemia. Endotoxin alone significantly produced hypotension, prostaglandins (TxB2, PGE2) release, and death. In contrast pretreatment with BN52021, a specific PAF receptor antagonist, significantly altered the hypotension, significantly attenuated the eicosanoid release, and improved the survival rate (p less than 0.01). These findings suggest that PAF receptor activation is an early event in endotoxemia. Eicosanoid release in endotoxemia could be related to PAF synthesis and PAF receptor activation. These findings support the hypothesis that there may be an intimate relationship between PAF and the eicosanoids and that in endotoxemia some of the effects of PAF may be mediated via the cyclo-oxygenase pathway.

Stroke in patients with fusiform vertebrobasilar aneurysms.

We studied seven patients with brainstem infarction and large fusiform vertebrobasilar (VB) aneurysms to clarify the clinical, radiologic, and pathologic features. All presented with pontine infarcts; one also had a cerebellar infarct. VB TIAs preceded brainstem infarction in four patients. Angiography and CT documented VB fusiform aneurysmal dilatation. Four had intraluminal thrombi and one had severe basilar artery stenosis. Two distinct clinical pictures emerged: unilateral pontine infarcts with favorable outcome, presumably related to obstruction of a pontine penetrating artery at its origin from the posterior wall of the aneurysmal basilar artery, and major fatal bilateral pontine infarcts from basilar artery occlusion. Two patients came to autopsy. One had thrombus in the dilated basilar artery and a posterior cerebral artery branch embolus with hemorrhagic occipital infarction; the other had basilar artery thrombus with aneurysmal rupture and subarachnoid hemorrhage. Fusiform VB aneurysms caused brainstem stroke by intraluminal thrombus, local embolism, atherostenosis, and obstruction of paramedian penetrating arteries. Subarachnoid hemorrhage is an uncommon complication.

Intracranial lesions shown by CT scans in 259 cases of first alcohol-related seizures.

We obtained CTs in 259 patients with a first alcohol-related convulsion. Each subject had generalized convulsions, recent abstinence from alcohol abuse, and no obvious etiology for seizures other than alcohol withdrawal. Patients with only focal seizures, major head injury, coma, or a severe toxic-metabolic disorder were excluded. We recorded history and signs of minor head injury, presence of headache, level of consciousness, neurologic signs, routine medical examination findings, and subsequent clinical course. Sixteen patients (6.2%) had intracranial lesions on CT. Eight had subdural hematomas or hygromas, two had vascular malformations, two had neurocysticercosis, and one each showed a Berry aneurysm, possible tumor, skull fracture with subarachnoid hemorrhage, and probable cerebral infarction. In ten cases (3.9%), clinical management was altered because of the CT result. History or signs of minor head trauma, headache, level of consciousness, or focal neurologic signs did not significantly correlate with CT abnormality.

Pentoxifylline in acute nonhemorrhagic stroke. A randomized, placebo-controlled double-blind trial.

The efficacy and safety of pentoxifylline were assessed in 297 adult patients with ischemic stroke in a multicenter, double-blind, randomized and placebo-controlled trial. Treatment was started within 12 hours after the stroke onset. Study medication was administered intravenously continuously (16 mg/kg/day, maximum 1,200 mg/day) for 3 days and per os (400 mg t.i.d.) for the remainder of 28 days. Demographic data were comparable, and functional impairment and mortality (pentoxifylline 12%, placebo 10%) were not different between the two groups. Neurologic deficit scores improved from baseline admission scores during the 4-week study in both groups but did not differ between groups at admission or throughout the study except during the first few days when the consciousness level (Days 1 and 2), motor function (Days 1 and 2), cranial nerve function (Days 1-4), and total neurologic deficit scores (Days 1 and 2) were better in the pentoxifylline group than in the placebo group, especially in a subset of patients with severe deficits at admission. Laboratory values and side effects were also comparable between groups. Our study indicates that pentoxifylline can be given safely in patients with acute ischemic stroke. Although pharmacologic effects were present during the first few days, the clinical benefits were small and not sustained.