Continuous wave Doppler echocardiography after surgical repair of coarctation of the aorta

Objective—To find how closely pressure gradients across the aortic arch derived from Doppler echocardiography reflect gradients measured by catheter after surgical repair of coarctation of the aorta.Design—Pressure drop across the aortic arch was measured simultaneously by continuous wave Doppler and double lumen catheter in 20 patients with repaired coarctation of the aorta.Results—The peak pressure drop estimated by Doppler was almost invariably higher than the peak to peak gradient measured by catheter, as might be expected. Wide variation was seen between the Doppler measured pressure drop and instantaneous peak gradient measured by catheter, ranging from +22 to −17 mm Hg. The reasons for these differences are unclear but are probably related to a combination of complex flow dynamics in the aortic arch, difficulty in closely aligning the Doppler beam with flow, and inability to measure flow velocity immediately proximal to the site of the surgical repair with continuous wave Doppler.Conclusions—Continuous wave Doppler echocardiography may significantly overestimate or underestimate the pressure drop after repair of coarctation and it should be interpreted with caution in individual patients. Catheterisation with angiography remains the reference standard for assessment of surgical repair of the aortic arch.     

Progressive and regressive changes in the nucleus pulposus. Part I. The neonate

Magnetic resonance (MR) imaging, correlated with anatomic sections, was used to characterize the progressive and regressive changes in the nucleus pulposus in neonates. The spines of five fetuses and five full-term infants between 16 and 40 weeks old were studied. In anatomic sections, the nucleus pulposus was sharply demarcated from the anulus fibrosus, Sharpey fibers were conspicuous, and a plate of primitive notochord was evident in the equator of the disk. On long repetition time (TR)/long echo time (TE) or long TR/short TE MR images, Sharpey fibers (low signal intensity) and notochord (low signal intensity) could be differentiated from the high-signal-intensity nucleus pulposus and anulus fibrosus. The major differences between the fetal and infant spines were the amount of notochord in the disk and ossification in the vertebral body.     

RNAi knock-down of the Litopenaeus vannamei Toll gene (LvToll) significantly increases mortality and reduces bacterial clearance after challenge with Vibrio harveyi

In this study, we used real-time PCR to simultaneously monitor the responses of 12 key genes of the shrimp innate immune system in Litopenaeus vannamei after challenge with Vibrio harveyi. In the proPO activating system, we found that proPO was up-regulated (3.3× control at 36 hpi). The hemolymph clotting genes transglutaminase (TGase) and clotting protein were also up-regulated, as were 5 genes in the antimicrobial peptide system (ALF, Crustin, Lyz, PEN2 and PEN4), with only PEN3 showing no significant changes. In the antioxidant defense system, SOD was slightly elevated while GPx was substantially down-regulated. In the pattern recognition receptor system, at 24 hpi, the Toll gene (LvToll) showed the highest relative increase in expression level of all the investigated genes (15× greater than the sterile seawater control). In the second part of this study, when LvToll was knocked down by RNAi silencing, there was no effect on either survival rates or bacterial number in unchallenged shrimp. There was also no difference in mortality rates between control shrimp and LvToll-silenced shrimp when these two groups were challenged with a viral pathogen (white spot syndrome virus; WSSV). However, when LvToll-silenced shrimp were challenged by V. harveyi, there was a significant increase in mortality and bacterial CFU counts. We note that the increase in bacterial CFU count occurred even though treatment with EGFP dsRNA had the opposite effect of reducing the CFU counts. We conclude that LvToll is an important factor in the shrimp innate immune response to acute V. harveyi infection, but not to WSSV.     

A breast cancer cell microarray (CMA) as a rapid method to characterize candidate biomarkers

Tissue microarrays (TMAs) have become an invaluable tool in cancer research to evaluate expression and subcellular localization of proteins in cells and tissues. As the catalogs of candidate biomarkers and therapeutic targets become more extensive, there is a need to characterize and validate these targets and biomarkers in cell lines as a primary biological system in research laboratories. Thus, cell microarrays (CMAs) are useful as a high-throughput screening tool. Here, we constructed a CMA containing 32 publicly available immortalized breast cell lines with the goal of creating a method to rapidly screen for antigens of interest in breast cancer research in a relatively easy, rapid and cost-effective manner. As proof of concept, we performed immunocytochemical staining of the HER2 receptor, as the status of this protein is relevant to breast cancer and has previously been reported for these cell lines. We observed a complete concordance of our staining with the published status of HER2 in these cell lines. In addition, we examined the expression of CD44, epithelial markers EpCAM and E-cadherin and tyrosine phosphoproteins. The labeling of these proteins correlates with the known biology of the cell lines. Our results demonstrate the utility of our method to screen for potential biomarkers and therapeutic targets in breast cancer and we suggest that CMAs be used as a general approach in breast cancer research.     

Working with capacity limitations: operations management in critical care

As your hospital's ICU director, you are approached by the hospital's administration to help solve ongoing problems with ICU bed availability. The ICU seems to be constantly full, and trauma patients in the emergency department sometimes wait up to 24 hours before receiving a bed. Additionally, the cardiac surgeons were forced to cancel several elective coronary-artery bypass graft cases because there was not a bed available for postoperative recovery. The hospital administrators ask whether you can decrease your ICU length of stay, and wonder whether they should expand the ICU to include more beds For help in understanding and optimizing your ICU's throughput, you seek out the operations management researchers at your university.     

Out of Pocket Expenditure for Sick Newborn Care in Referral Hospitals of Nepal

Background

Almost all preventable neonatal deaths take place in low- and middle-income countries and affect the poorest who have the least access to high quality health services. Cost of health care is one of the factors preventing access to quality health services and universal health coverage. In Nepal, the majority of expenses related to newborn care are borne by the caregiver, regardless of socioeconomic status. We conducted a study to assess the out of pocket expenditure (OOPE) for sick newborn care in hospitals in Nepal.

Methods

This cross-sectional study of hospital care for newborns was conducted in 11 hospitals in Nepal and explored OOPE incurred by caregivers for sick newborn care. Data were collected from the caregivers of the sick newborn on the topics of cost of travel, accommodation, treatment (drugs, diagnosis) and documented on a sick newborn case record form.

Results

Data were collected from 814 caregivers. Cost of caregivers’ stay accounted for more than 40% of the OOPE for sick newborn care, followed by cost of travel, and the baby’s stay and treatment. The overall OOPE ranged from 13.6 to 226.1 US dollars (USD). The median OOPE was highest for preterm complications ($33.2 USD; CI 14.0–226.1), followed by hyperbilirubinemia ($31.9 USD; CI 14.0–60.7), respiratory distress syndrome ($26.9 USD; 15.3–121.5), neonatal sepsis ($ 25.8 USD; CI 13.6–139.8) and hypoxic ischemic encephalopathy ($23.4 USD; CI 13.6–97.7).

Discussion for practice

In Nepal, OOPE for sick newborn care in hospitals varied by neonatal morbidity and duration of stay. The largest proportion of OOPE were for accommodation and travel. Affordable and accessible health care will substantially reduce the OOPE for sick newborn care in hospitals.