Disposable platform provides visual and color-based point-of-care anemia self-testing

BACKGROUND. Anemia, or low blood hemoglobin (Hgb) levels, afflicts 2 billion people worldwide. Currently, Hgb levels are typically measured from blood samples using hematology analyzers, which are housed in hospitals, clinics, or commercial laboratories and require skilled technicians to operate. A reliable, inexpensive point-of-care (POC) Hgb test would enable cost-effective anemia screening and chronically anemic patients to self-monitor their disease. We present a rapid, stand-alone, and disposable POC anemia test that, via a single drop of blood, outputs color-based visual results that correlate with Hgb levels.METHODS. We tested blood from 238 pediatric and adult patients with anemia of varying degrees and etiologies and compared hematology analyzer Hgb levels with POC Hgb levels, which were estimated via visual interpretation using a color scale and an optional smartphone app for automated analysis.RESULTS. POC Hgb levels correlated with hematology analyzer Hgb levels (r = 0.864 and r = 0.856 for visual interpretation and smartphone app, respectively), and both POC test methods yielded comparable sensitivity and specificity for detecting any anemia (n = 178) (<11 g/dl) (sensitivity: 90.2% and 91.1%, specificity: 83.7% and 79.2%, respectively) and severe anemia (n = 10) (<7 g/dl) (sensitivity: 90.0% and 100%, specificity: 94.6% and 93.9%, respectively).CONCLUSIONS. These results demonstrate the feasibility of this POC color-based diagnostic test for self-screening/self-monitoring of anemia.TRIAL REGISTRATION. Not applicable.FUNDING. This work was funded by the FDA-funded Atlantic Pediatric Device Consortium, the Georgia Research Alliance, Children’s Healthcare of Atlanta, the Georgia Center of Innovation for Manufacturing, and the InVenture Prize and Ideas to Serve competitions at the Georgia Institute of Technology.     

Development of innervation within syngeneic thymus tissue transplanted under the kidney capsule of the nude mouse: a light and ultrastructural microscope study

The developing thymus, prior to the onset of its functional and structural organization, is innervated by the autonomic nervous system (ANS). The present study extends these earlier findings by analyzing at the light and ultrastructural microscope level the distribution of ANS nerves within normal 18-day-old embryo thymus, adult thymus, and thymic tissue transplanted under the kidney capsule of syngeneic nude mice. The results of this study showed that prior to birth the murine thymus is innervated by AChE-positive fibers that are distributed at the corticomedullary boundaries and throughout the adjacent cortex, as well as to cells beneath the thymic capsule. This pattern of distribution remains constant during adult life. The examination of the various thymic tissues by ultrastructural analysis demonstrated that myelinated and nonmyelinated fiber bundles penetrate the thymic capsule and the interface between the kidney and the thymus transplant. The myelinated fibers measured 2 micron or less in diameter; the nonmyelinated fibers were 1 micron in diameter. Myelination did not accompany the nerves into the parenchyma of the normal gland but was observed in the intralobular trabeculae of the transplanted thymus. Subcapsular nerves form a network that terminates among the thymocytes, whereas intrathymic nerves enter the parenchyma in bundles along the vasculature and interlobular septa before penetrating into the deeper layers of the thymic cortex. Some larger nerve fibers terminate in the corticomedullary boundaries and in the interlobular septa. Smaller fibers form en passant boutons near parenchymal cells. The innervation of both the normal thymus and the transplanted thymus prior to the onset of thymic immune function supports a role for ANS innervation in the development of thymic competency.     

Selective blockade by nifedipine of ''purinergic'' rather than adrenergic nerve-mediated vasopressor responses in the pithed rat.

1. Nifedipine can attenuate pressor responses to sympathetic nerve stimulation both in the presence and in the absence of alpha-adrenoceptor blocking agents. 2. In the presence of alpha,beta-methylene ATP, nifedipine produces only a small attenuation of the vasopressor response. 3. Nifedipine attenuates the vasopressor response produced by intravenous bolus administration of alpha,beta-methylene ATP. 4. The results suggest that the purinergic component of the vasopressor response to stimulation of the sympathetic outflow in the rat is subject to blockade by nifedipine, whereas the alpha-adrenoceptor-mediated response to co-transmitter noradrenaline is relatively resistant.     

Traumatic ventricular septal defects

Two previously unreported cases of traumatic ventricular septal defect are presented. One, which is an unusual occurrence, has been diagnosed on clinical evidence as a ventricular septal defect resulting from a gunshot wound of the chest. The defect has been successfully repaired in one of the patients. The etiology, prognosis and indications for operation in these cases are briefly discussed.     

Controlled Ultrafiltration During Single-Pass Dialysis with the RP-6 Dialyzer and Evaluation of Its Time-Dependent Ultrafiltration Index

A simple and inexpensive method is described for controlling ultrafiltration when using the high flux RP-6 dialyzer. When the RP-6 is operated in the co-current mode and with single-pass dialysate delivery, (P_bo-P_dn) can be used to accurately and safely control ultrafiltration. Combined results from ten dialyses indicate there is a pressure-dependent concentration polarization which affects ultrafiltration as reported previously, and in addition, a time-dependent effect indicating a more complex dialyzer/blood interaction. The ultrafiltration index decreases linearly with time. The ultrafiltration can be adequately predicted by
Q v =16.1 ml/hr-mmHg [1–0.0761/hr t] (P_Bo-P_Do)