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Analysis of human remains and a copper band found in the center of a Late Archaic (ca. 5000–3000 cal BP) shell ring demonstrate an exchange network between the Great Lakes and the coastal southeast United States. Similarities in mortuary practices suggest that the movement of objects between these two regions was more direct and unmediated than archaeologists previously assumed based on “down-the-line” models of exchange. These findings challenge prevalent notions that view preagricultural Native American communities as relatively isolated from one another and suggest instead that wide social networks spanned much of North America thousands of years before the advent of domestication.
Alteplase is an effective treatment for ischaemic stroke patients, and it is widely available at all primary stroke centres. The effectiveness of alteplase is highly time-dependent. Large tertiary centres have reported significant improvements in their door-to-needle (DTN) times. However, these same improvements have not been reported at community hospitals.
Red Deer Regional Hospital Centre (RDRHC) is a community hospital of 370 beds that serves approximately 150,000 people in their acute stroke catchment area. The RDRHC participated in a provincial DTN improvement initiative, and implemented a streamlined algorithm for the treatment of stroke patients. During this intervention period, they implemented the following changes: early alert of an incoming acute stroke patient to the neurologist and care team, meeting the patient immediately upon arrival, parallel work processes, keeping the patient on the Emergency Medical Service stretcher to the CT scanner, and administering alteplase in the imaging area. Door-to-needle data were collected from July 2007 to December 2017.
A total of 289 patients were treated from July 2007 to December 2017. In the pre-intervention period, 165 patients received alteplase and the median DTN time was 77 minutes [interquartile range (IQR): 60–103 minutes]; in the post-intervention period, 104 patients received alteplase and the median DTN time was 30 minutes (IQR: 22–42 minutes) (p < 0.001). The annual number of patients that received alteplase increased from 9 to 29 in the pre-intervention period to annual numbers of 41 to 63 patients in the post-intervention period.
Community hospitals staffed with community neurologists can achieve median DTN times of 30 minutes or less.
The incidence of recreational water-associated outbreaks in the United States has significantly increased, driven, at least in part, by outbreaks both caused by Cryptosporidium and associated with treated recreational water venues. Because of the parasite's extreme chlorine tolerance, transmission can occur even in well-maintained treated recreational water venues (e.g. pools) and a focal cryptosporidiosis outbreak can evolve into a community-wide outbreak associated with multiple recreational water venues and settings (e.g. childcare facilities). In August 2004 in Auglaize County, Ohio, multiple cryptosporidiosis cases were identified and anecdotally linked to pool A. Within 5 days of the first case being reported, pool A was hyperchlorinated to achieve 99·9% Cryptosporidium inactivition. A case-control study was launched to epidemiologically ascertain the outbreak source 11 days later. A total of 150 confirmed and probable cases were identified; the temporal distribution of illness onset was peaked, indicating a point-source exposure. Cryptosporidiosis was significantly associated with swimming in pool A (matched odds ratio 121·7, 95% confidence interval 27·4–∞) but not with another venue or setting. The findings of this investigation suggest that proactive implementation of control measures, when increased Cryptosporidium transmission is detected but before an outbreak source is epidemiologically ascertained, might prevent a focal cryptosporidiosis outbreak from evolving into a community-wide outbreak.
We analyzed a 10-year stroke administrative dataset to examine trends in admissions, mortality, and discharge destination in Canada.
We conducted an analysis of hospital administrative data from April 1st 2003 to March 31st 2013 from the Canadian Institute of Health Information’s Discharge Abstract Database. Ten-year trends for population-based age- and sex-standardized admission rates were calculated. We reviewed 10-year trends in absolute stroke admissions for differences between provinces and age groups. Stroke 30-day in-hospital mortality rates were calculated and adjusted for sex, age, stroke type and comorbidities. We documented changes in discharge location for ischemic and hemorrhagic stroke patients discharged from acute care.
The rate of hospital admissions has declined from 140.2 to 117.5 (per 100,000 people). The number of absolute stroke admissions within provinces increased in Alberta and British Columbia (21.7% and 16.2% respectively). The proportion of stroke patients aged 40-69 years old increased by 4.8% (p<0.0001) over the 10 years, whereas the proportion aged over 70 decreased by 4.9% (p<0.0001). Risk-adjusted 30-day in-hospital mortality decreased from: 18.5% to 14.9% for all strokes; 15.2% to 12.1% for ischemic strokes; 35.6% to 29.7% for intracerebral hemorrhage; and 25.1% to 18.0% for subarachnoid hemorrhage. The absolute increase in patients requiring inpatient and outpatient support increased by 4% (p<0.0001).
The rate of admissions for stroke is decreasing but there is an increase in stroke admissions for younger patients. In-hospital mortality is decreasing; fewer patients are going directly home without services and more are requiring support services.
Sildenafil is frequently prescribed to children with single ventricle heart defects. These children have unique hepatic physiology with elevated hepatic pressures, which may alter drug pharmacokinetics. We sought to determine the impact of hepatic pressure on sildenafil pharmacokinetics in children with single ventricle heart defects.
A population pharmacokinetic model was developed using data from 20 single ventricle children receiving single-dose intravenous sildenafil during cardiac catheterisation. Non-linear mixed effect modelling was used for model development, and covariate effects were evaluated based on estimated precision and clinical significance.
The analysis included a median (range) of 4 (2–5) pharmacokinetic samples per child. The final structural model was a two-compartment model for sildenafil with a one-compartment model for des-methyl-sildenafil (active metabolite), with assumed 100% sildenafil to des-methyl-sildenafil conversion. Sildenafil clearance was unaffected by hepatic pressure (clearance=0.62 L/hour/kg); however, clearance of des-methyl-sildenafil (1.94×(hepatic pressure/9)−1.33 L/hour/kg) was predicted to decrease ~7-fold as hepatic pressure increased from 4 to 18 mmHg. Predicted drug exposure was increased by ~1.5-fold in subjects with hepatic pressures ⩾10 versus <10 mmHg (median area under the curve=533 versus 792 µg*h/L).
Elevated hepatic pressure delays clearance of the sildenafil metabolite – des-methyl-sildenafil – and increases drug exposure. We speculate that this results from impaired biliary clearance. Hepatic pressure should be considered when prescribing sildenafil to children. These data demonstrate the importance of pharmacokinetic assessments in patients with unique cardiovascular physiology that may affect drug metabolism.
Longitudinal, patient-level data on resource use and costs after an ischemic stroke are lacking in Canada. The objectives of this analysis were to calculate costs for the first year post-stroke and determine the impact of disability on costs.
The Economic Burden of Ischemic Stroke (BURST) Study was a one-year prospective study with a cohort of ischemic stroke patients recruited at 12 Canadian stroke centres. Clinical history, disability, health preference and resource utilization information was collected at discharge, three months, six months and one year. Resources included direct medical costs (2009 CAN$) such as emergency services, hospitalizations, rehabilitation, physician services, diagnostics, medications, allied health professional services, homecare, medical/assistive devices, changes to residence and paid caregivers, as well as indirect costs. Results were stratified by disability measured at discharge using the modified Rankin Score (mRS): non-disabling stroke (mRS 0-2) and disabling stroke (mRS 3-5).
We enrolled 232 ischemic stroke patients (age 69.4 ± 15.4 years; 51.3% male) and 113 (48.7%) were disabled at hospital discharge. The average annual cost was $74,353; $107,883 for disabling strokes and $48,339 for non-disabling strokes.
An average annual cost for ischemic stroke was calculated in which a disabling stroke was associated with a two-fold increase in costs compared to NDS. Costs during the hospitalization to three months phase were the highest contributor to the annual cost. A “back of the envelope” calculation using 38,000 stroke admissions and the average annual cost yields $2.8 billion as the burden of ischemic stroke.
The “chronic cerebrospinal venous insufficiency” or “CCSVI” hypothesis, namely that multiple sclerosis (MS) is caused by abnormalities in the azygous and internal jugular veins with subsequent alterations in venous hemodynamics in the central nervous system, has been a dominant topic in MS care in Canada over the past year. Although there is no methodologically rigorous evidence to support this hypothesis presently, a considerable number of MS patients have undergone endovascular CCSVI procedures. Such procedures include angioplasty or stent placement in jugular and azygous veins. The safety and efficacy of these procedures is unknown, but not without risk.
Chart and patient review of five patients with confirmed MS followed in Calgary were undertaken after patients came to medical attention by referral or admission secondary to complications believed to be associated with CCSVI procedures.
Complications upon investigation and review included internal jugular vein stent thrombosis, cerebral sinovenous thrombosis, stent migration, cranial nerve injury and injury associated with venous catheterization.
As the debate about CCSVI and its relationship to MS continues, the complications and risks associated with venous stenting and angioplasty in jugular and azygous veins are becoming clearer. As increasing numbers of MS patients are seeking such procedures, these five cases represent the beginning of a wave of complications for which standardized care guidelines do not exist. Our experience and that of our colleagues will be used to develop guidelines and strategies to monitor and manage these patients as their numbers increase.
This article provides an overview of the New Zealand Health, Work and Retirement Study (HWR), the focus of which is on determinants of cultural-contextual factors on physical and mental health among 6,662 New Zealand citizens, a nationally representative sample of adults between 55 and 70 years of age. The HWR was initiated in 2006 with two-year re-assessment intervals. The health and wellbeing of older Māori was a study priority as previous research has shown large health disparities between Māori and non-Māori in New Zealand. Persons of Māori origin were over-sampled to ensure adequate information for subsequent analyses. First-wave results indicated that socioeconomic status, social support and retirement status were associated with optimal ageing among older adults in New Zealand. Māori scored lower on markers of physical and mental health, which was partially explained by restrictive factors including reduced economic living standards and a propensity towards less physical activity. After controlling for multiple socio-contextual and biological variables, ethnicity continued to predict health, suggesting that there are other markers of health and wellbeing in ageing among Māori. Structural variables which restrict access to health care and predispose Māori to engage in maladaptive lifestyle behaviours combined with the distal effects of colonisation may contribute to the health disparities found between Māori and the majority population in New Zealand.
Previous studies have shown that En-1, a homeobox-containing gene, maps close to or at the Dh locus in the mouse. Since homeobox-containing genes are key genes in the control of development the close proximity of En-1 to the developmentally significant gene Dh raised the possibility that the Dh mutation represented a mutant allele of En-1. A genetic analysis involving En-1, Dh, and other chromosome 1 markers (Emv-17, In and Pep-3) shows that although Dh and En-1 are closely linked they are separable by recombination (4/563). The likely gene order and recombination frequencies of these loci are: In (5.2±0.9) Emv-17 (1.1±0.4) Dh (0.7±0.4) En-1 (3.0±0.7) Pep-3. This shows that Dh is not a mutant allele of En-1.
Accuracy of intracranial magnetic resonance angiography (MRA) and reliability of interpretation are not well established compared to conventional selective catheter angiography. The purpose of this study was to determine the accuracy of MRA in evaluation of intracranial vessels in acute stroke and transient ischemic attack (TIA) patients.
Twenty-nine patients (seven females, 22 males; median age 53) with acute stroke or TIA were enrolled into the study. All patients underwent both MRA using a 3 T clinical magnet and conventional angiography within 48 hours. Median time between MRA and angiography was 263 minutes. Conventional angiography preceded MRA in 15 cases. Fourteen patients received thrombolysis during MRA or angiography. National Institutes of Health Stroke Scale scores were obtained prior to the MR exam. One neuroradiologist rated all conventional angiograms, which were used as gold standard. Five observers, blinded to conventional angiography results and all clinical information except symptom side, rated the MR angiograms. Kappa statistics were used to assess reliability; contingency tables were used to assess accuracy of non-enhanced and enhanced MRA.
Two hundred and fifty two intracranial vessels were assessed. Agreement between raters was good for both non-enhanced (k=0.50) and gadolinium-enhanced (k=0.46) images. There were a total of 26 vessels occluded by DSA. Overall, the non-enhanced MRA showed sensitivity of 84.2% (95% CI 60.4-96.6) and specificity of 84.6% (95% CI 78.6-89.4). The enhanced MRA showed sensitivity of 69.2 (95% CI 38.6-90.9) and specificity of 73.6 (95% CI 65.5-80.7).
Magnetic resonance angiography is a good non-invasive screening tool for assessing intracranial vessel status in acute ischemic stroke. Angiography remains the gold standard for definitive assessment of the intracranial circulation.
Polyclonal antibodies to purified recombinant barley haemoglobin (Hb) have been raised in rabbits and used to investigate its expression in monocotyledonous plants. Very little or no Hb expression was observed in dry barley seeds but germination resulted in the expression of Hb which peaked at 2–3 days after imbibition. Hb expression was also observed in maize, wheat, wild oat and Echinochloa crus-galli seeds during germination. Dissection of tissues from the barley seedlings showed that most of the haemoglobin was expressed in the root and seed coat (aleurone layer), with very little in the coleoptile. Imbibition of half-seeds or excised embryos resulted in the expression of haemoglobin. ATP measurements of barley embryos showed that ATP levels quickly increase after imbibition. α-Amylase activity was also determined in embryos to correlate Hb expression with a well-characterized germination response. The results demonstrate that Hb expression is a normal consequence of germination.
As the role of paramedics evolves, evaluation of their ability to accomplish an expanded scope of practice is necessary. The objective of this study was to determine whether specially trained paramedics can monitor and treat patients appropriately during interfacility transports that traditionally have required the use of supplemental, hospital-based personnel.
A paramedic-staffed mobile intensive care unit was developed as a cooperative program between Huron Valley Ambulance and the Washtenaw/Livingston County Medical Control Authority. This prospective observational study involved 111 patients requiring interfacility transport, conveyed by a paramedic-staffed mobile intensive care unit. A change in the Acute Physiologic and Chronic Health Evaluation (APACHE II) score components of mean arterial pressure, heart rate, and respiratory rate at the beginning and end of the transport was used to evaluate the ability of the paramedics to accomplish the transfer appropriately.
APACHE II scares increased in 20 patients, decreased in 16, and were unchanged in 75. The mean value for the change in APACHE score was 0.11 (95% confidence interval: −0.11−0.33).
Specially trained paramedics can monitor and treat patients appropriately during interfacility transfers that traditionally would have required supplementation with additional hospital staff.
The linear polarization of the Crab pulsar as a function of pulse phase was observed by the High Speed Photometer on the Hubble Space Telescope in March, 1993. Observations were obtained in a bandpass centered on 2770 A using a 0.25 ms sample time, corresponding to a time resolution of 0.0075 in pulse phase. The UV polarization of the pulsar [Fig. 1] is strikingly similar to that observed in the visible (cf. Smith et al. 1988). The same values of polarization and the same swing of position angle occur through the main and secondary pulses. The polarization pulse profile must be essentially wavelength independent at frequencies above the infrared.