A versatile cryo-transfer system, connecting cryogenic focused ion beam sample preparation to atom probe microscopy.

Atom probe tomography (APT) is a powerful technique to obtain 3D chemical and structural information, however the 'standard' atom probe experimental workflow involves transfer of specimens at ambient conditions. The ability to transfer air- or thermally-sensitive samples between instruments while maintaining environmental control is critical to prevent chemical or morphological changes prior to analysis for a variety of interesting sample materials. In this article, we describe a versatile transfer system that enables cryogenic- or room-temperature transfer of specimens in vacuum or atmospheric conditions between sample preparation stations, a focused ion beam system (Zeiss Crossbeam 540) and a widely used commercial atom probe system (CAMECA LEAP 4000X HR).

The Relationship Between Attitudes about Research and Health Literacy among African American and White (Non-Hispanic) Community Dwelling Older Adults.

Background: Ethnic minority representation lacks in research. Understanding factors that promote minorities in research helps address this participation gap. Minorities often face representation disparities, including health education, socioeconomic status, and race.

Positive Impacts of a Sport Intervention on Male Students of Color and School Climate.

A positive school climate is strongly associated with enhanced student outcomes. With the disengagement of Black and Latinx youth living in poverty being at an all-time high, participation in sport-based youth development (SBYD) programs may enhance school climate, while capitalizing on existing interests. The purpose of this study was to examine the impact of a SBYD intervention on male students of color and school climate.

A simple approach to atom probe sample preparation by using shadow masks.

Here, we present a new method that utilises shadow masks in a broad ion beam system to prepare atom probe samples. It is particularly suited to non-conductors and materials with surface layers such as surface oxides, implanted layers or thin films. This new approach bypasses the focused ion beam (FIB) lift-out step, increasing the sample throughput, dramatically reducing the required FIB beam time and decreasing the complexity of sample preparation.

Unsuspected rejection episodes on routine surveillance endomyocardial biopsy post-heart transplant in paediatric patients.

The use of routine endomyocardial biopsies post-heart transplant in children remains controversial. It is generally accepted as the gold standard for detecting rejection, but details of the surveillance protocol, such as number and timing of biopsies, remain uncertain, with suggestions that recent advances in immunosuppressant therapy have obviated the need to perform surveillance biopsies. We retrospectively analysed results of endomyocardial biopsies performed in our unit since the introduction of a policy of three routine biopsies in the first six months post-transplantation.

Reduction of transmissible spongiform encephalopathy infectivity from human red blood cells with prion protein affinity ligands.

Background: There is a demonstrated risk of infection by transmissible spongiform encephalopathies (TSEs) through transfusion from asymptomatic donors. Currently, blood-borne TSE infectivity cannot be detected with a diagnostic test, nor is it likely to be amenable to inactivation; however, its depletion with specific adsorp-tive ligand resins is possible.

Study Design And Methods: Six ligands that bind the prion protein, PrP, were selected by screening large solid-phase combinatorial chemical libraries.

Transfusion via the carotid artery in the hamster.

Public health policy makers need quantitative scientific data to assess the risk to the blood supply posed by transmissible spongiform encephalopathy (TSE) diseases. To this end, our laboratory has developed a model of blood-borne TSE infectivity in hamsters infected with the 263K strain of scrapie, an experimental model of choice for quantitative studies of TSE infectivity. We report here a microsurgical method for cannulation of the carotid artery in the hamster that allows transfusion of a large fraction of the blood volume of the hamster, with virtually no blood loss to the surgical site or exposure to nervous tissue.

Aggressive active case detection: a malaria control strategy based on the Brazilian model.

Since 1996, the Brazilian Ministry of Health has adopted a malaria control strategy known as aggressive active case detection (AACD) in which most or all members of every community are tested and treated for malaria on a monthly basis. The strategy attempts to identify and treat cases of asymptomatic malaria, which, if untreated, continue to transmit the infection. Malaria remains uncontrolled because almost all health care systems in the world rely on passive case detection: the treatment of only symptomatic cases of malaria.

Viral chemokine-binding proteins inhibit inflammatory responses and aortic allograft transplant vasculopathy in rat models.

Background: Both CC and CXC chemokines direct monocyte and T-cell migration and activation at sites of vascular injury, but the relative contributions of each chemokine class to transplant vasculopathy development have not been defined. The nonselective C, CC, and CXC chemokine binding protein, M-T7, inhibits vasculopathy development after angioplasty and after renal transplant. We have assessed the effects of three viral chemokine-binding proteins with differing ranges of chemokine inhibition on plaque growth in rats after aortic allograft transplant.

Partitioning of TSE infectivity during ethanol fractionation of human plasma.

The practice of validating processes for their capacity to inactivate a range of non-enveloped and enveloped viruses also provides confidence that plasma products will be safe from emerging viral pathogens with known aetiology. Of greater concern are diseases of unknown or poorly defined aetiology such as the group of neurological diseases collectively called the transmissible spongiform encephalopathies (TSEs), or prion diseases, for which the best known human disease is Creutzfeldt-Jakob Disease (CJD) and its variant form (vCJD). The goal of the current study was to investigate the potential for manufacturing steps used in the production of albumin and immunoglobulin products by Kistler-Nitschmann fractionation, and the utility of nanofiltration of immunoglobulin to remove TSE agents.

Inactivation of viral and prion pathogens by gamma-irradiation under conditions that maintain the integrity of human albumin.

Background And Objectives: The administration of therapeutic plasma protein concentrates has been associated with the real risk of transmitting viral diseases and the theoretical risks of prion transmission. Our objective was to determine if gamma-irradiation can inactivate viral or prion infectivity without damaging a protein biotherapeutically.

Materials And Methods: Human albumin 25% solution, spiked with four model viruses (including porcine parvovirus) or with brain homogenate from scrapie-infected hamsters, was gamma-irradiated at constant low-dose rates and assayed for viral and prion infectivity or for albumin integrity.

Scrapie infectivity in hamster blood is not associated with platelets.

The infectivity of hamster scrapie strain 263K was measured in platelets isolated from blood pooled from six hamsters with clinical scrapie. The total number of infectious doses present in the blood pool was 220, out of which only 3.5 infectious doses were associated with platelets.

The viral anti-inflammatory chemokine-binding protein M-T7 reduces intimal hyperplasia after vascular injury.

Chemokines and IFN-gamma function as central regulators of inflammatory responses to vascular injury. Both classes of cytokines are upregulated during restenosis, a response to vascular injury that leads to recurrent atherosclerotic plaque growth, but the relative impact of each class of cytokines remains undetermined. M-T7 is a secreted myxoma viral immunomodulatory glycoprotein that functions both as a species-specific inhibitor of rabbit IFN-gamma and as a chemokine-binding protein, interacting with a wide range of C, C-C, and C-X-C chemokines in a species-nonspecific fashion.

The distribution of infectivity in blood components and plasma derivatives in experimental models of transmissible spongiform encephalopathy.

Background: The administration of blood components from donors who subsequently develop Creutzfeldt-Jakob disease has raised the issue of blood as a possible vehicle for iatrogenic disease.

Study Design And Methods: We examined infectivity in blood components and Cohn plasma fractions in normal human blood that had been "spiked" with trypsinized cells from a scrapie-infected hamster brain, and in blood of clinically ill mice that had been inoculated with a mouse-adapted strain of human transmissible spongiform encephalopathy. Infectivity was assayed by intracerebral inoculation of the blood specimens into healthy animals.

Classifying cervical cells using a recurrent neural network by building basins of attraction.

This paper describes the result of classifying cervical cells employing a novel way of using a Hopfield-style neural network for classification. This method could be used as part of an automated cervical screening system. Rather than storing the exemplars (training elements) as stable points, a connection matrix is determined, using perceptron-type learning, such that the exemplars are placed in basins of attraction.

Plasma pharmacokinetics and tissue distribution of paclitaxel in CD2F1 mice.

We defined the pharmacokinetics of paclitaxel after i.v., i.

Local versus general anesthesia for lumbar percutaneous discectomy.

Ninety-two adult patients scheduled for automated percutaneous discectomy (PERC) were assigned to receive either local anesthesia supplemented with monitored i.v. analgesia (MIVA) or general endotracheal anesthesia (GA-LITE).

ZDV delays but does not prevent the transmission of MAIDS by LP-BM5 MuLV-infected macrophage-monocytes.

LP-BM5 MuLV infection of monocyte-macrophages (MM cells) and the ability of MM cells infected with this murine oncornavirus complex to transmit murine acquired immune deficiency syndrome (MAIDS) were assessed. Adherent cells expressing Mac-1 antigen (Mac-1+) were isolated from the peritoneum of infected C57BL/6 mice at weekly intervals postinoculation. A small percentage of MM cells was infected by 7 days after inoculation with LP-BM5 MuLV and virus production could be detected in MM cells throughout the course of disease.

Effect of 3'azidothymidine administered in drinking water or by continuous infusion on the development of MAIDS.

LP-BM5 MuLV infection of C57BL/6 mice induces a well characterized, lymphoproliferative, immunodeficiency disease (MAIDS), which is useful for evaluation of potential antiviral agents, because of the reproducibility of virological and clinical endpoints. This MAIDS retrovirus model was used to evaluate 3'azido-2,3'dideoxythymidine (AZT), using different doses, methods of administration and timing for initiation and continuation of therapy. AZT therapy 1 mg/ml in the drinking water given 30 days prior to virus challenge, and continued for 16 weeks, prevented LP-BM5 MuLV dissemination and disease in 13 of 15 treated mice.

Transmission in NFS/N mice of the heritable spongiform encephalopathy associated with the gray tremor mutation.

It has been shown that the autosomal recessive mutation, gray tremor (gt) was associated in the homozygous state (gt/gt) with a rapidly fatal spongiform encephalopathy. Heterozygotes (+/gt) developed mild asymptomatic spongiform brain lesions as did recipient inbred mice inoculated with gt/gt brain homogenates, some of whom also showed behavioral abnormalities [Sidman, R. L.