Cadaver lungs for transplantation. Effect of ventilation with alveolar gas

In an effort to increase the donor pool for lung transplantation (LTX), we have demonstrated the feasibility of LTX from circulation-arrested cadavers in a canine LTX model. We hypothesized that ventilation of the cadaver lung with alveolar gas (20% O2, 5% CO2, balance N2) (AG) would be superior to ventilation with 100% oxygen (O2) after circulatory arrest of the donor. Twelve mongrel dogs were intubated, heparinized and euthanized by pentothal injection and ventilated with AG (n=6) or O2 (n=6). Four hours later, donor animals underwent sternotomy, and the lungs were flushed with cold modified Euro-Collins solution, harvested, and stored inflated in ice slush. Left lung allotransplantation was performed, and recipients were made dependent o n the transplanted lung by occlusion of the contralateral bronchus and pulmonary artery. Recipient animals were ventilated with an FiO2 of 0.4 and followed for 8 hr. Total ischemic time was 7.9 hr for both groups. Pulmonary edema developed in all recipients of AG lungs; one recipient survived the 8-hr observation period with poor oxygenation. In contrast, three of six recipients of O2-ventilated lungs survived for 8-hr with excellent gas exchange. Specimens of donor lungs before and after transplant were evaluated histologically utilizing trypan blue exclusion as an indicator of cell viability. At the time of organ retrieval 4 hr after death, 6% of cells were nonviable in the O2-ventilated cadaver lungs. Circulation-arrested cadaver lungs ventilated with 100% O2 prior to organ retrieval have superior pulmonary function after transplant compared with lungs ventilated with AG. Ventilation of cadaver lungs with AG induces pulmonary injury in this model. retrieval of donor lungs from circulation-arrested cadavers has potential for increasing the pulmonary donor pool.     

Absence of detectable human herpesvirus 8 in the semen of human immunodeficiency virus-infected men without Kaposi's sarcoma

The prevalence of human herpesvirus 8 (HHV-8)/Kaposi's sarcoma (KS)-associated herpesvirus was investigated in the semen of 99 human immunodeficiency virus (HIV)-infected men (median CD4 cell count, 357/mm3) by use of a polymerase chain reaction (PCR) assay capable of detecting <10 copies of HHV-8 DNA. Of the subjects, 95 (96%) self-identified as men who have sex with men (MSM), and 3 had a history of clinical KS. Seminal cell specimens were negative for HHV-8 in 98 subjects. None of the 26 without KS (27.1% of 96 tested) who were seropositive for HHV-8 by IFA for latency-associated nuclear antigens had HHV-8 detected in their semen. The only subject with any evidence for seminal HHV-8 DNA was seropositive for HHV-8 and had active KS. HHV-8 was detected in 10 (10.4%) of 96 peripheral blood mononuclear cell specimens. The prevalence of HHV-8 DNA by PCR in semen of HIV-infected MSM without KS is low.     

An Experimental Investigation into the Feed Rate Capacity of Rotary Valve and Blow Tank Feeders

Industry widely uses rotary valves and blow tanks for the pneumatic conveying of products, each having their pros and cons depending on the specific application. This article shows the differing results obtained when low-velocity conveying a product through a common pipeline using both a drop-through rotary valve and a bottom-discharge blow tank feeder. A number of issues arise in the rotary valve system, the main one being rotary valve air leakage. A blow tank system, on the other hand, does not leak, as it is an enclosed system. The experimental results show dramatic differences in product throughput. Further exploration leads to a novel modification being made to the rotary valve system in an attempt to increase its capacity. The result of this modification shows a slight increase in output tonnage, but still significantly less than that obtained from the blow tank.     

P#: a concurrent Prolog for the .NET framework

We discuss P#, our implementation of a tool that allows interoperation between a concurrent superset of the Prolog programming language and C#. This enables Prolog to be used as a native implementation language for Microsoft's .NET platform. P# compiles a linear logic extension of Prolog to C# source code. We can thus create C# objects from Prolog and use C#'s graphical, networking and other libraries. We add language constructs on the Prolog side that allow concurrent Prolog code to be written. A primitive predicate is provided that evaluates a Prolog structure on a newly forked thread. Communication between threads is based on the unification of variables contained in such a structure. It is also possible for threads to communicate through a globally accessible table. All of the new features are available to the programmer through new built-in Prolog predicates. We discuss two software engineering tools implemented using P#. Copyright © 2004 John Wiley & Sons, Ltd.     

Collaborative cross-checking to enhance resilience

Resilience, the ability to adapt or absorb disturbance, disruption, and change, may be increased by team processes in a complex, socio-technical system. In particular, collaborative cross-checking is a strategy where at least two individuals or groups with different perspectives examine the others’ assumptions and/or actions to assess validity or accuracy. With this strategy, erroneous assessments or actions can be detected quickly enough to mitigate or eliminate negative consequences. In this paper, we seek to add to the understanding of the elements that are needed in effective cross-checking and the limitations of the strategy. We define collaborative cross-checking, describe in detail three healthcare incidents where collaborative cross-checks played a key role, and discuss the implications of emerging patterns.     

Pigeon perception and discrimination of rapidly changing texture stimuli

The perception and discrimination of rapidly changing texture stimuli by pigeons was examined in a target localization task. Five experienced pigeons were rewarded for finding and pecking at a randomly placed odd target block of small repeated elements embedded in a larger rectangular array of contrasting distractor elements. On dynamic color test trials, the color of the target, distractor, or both of these regions changed at rates of 100, 250, 500, or 1000 ms per frame. The number of colors appearing within such trials also varied. Pigeons performed well above chance in all test conditions, with target-associated changes producing the best discrimination. The results suggest: (a) global relational information can exclusively guide target localization behavior, (b) pigeons can perceptually group and segregate colored textured differences quite rapidly (< or = 100 ms), and (c) pigeons may possess automatic search control processes that can be captured by stimulus-driven changes in the display.     

Renal length in sickle cell disease: observations from a cohort study

Renal length has been measured by ultrasound in 237 subjects with homozygous sickle cell (SS) disease, 147 with sickle cell-hemoglobin C (SC) disease, and in 78 age-matched controls with a normal hemoglobin (AA) genotype. As expected, renal length increased with age in all genotypes but mean length was significantly greater in SS disease compared with SC disease (mean difference 4.3 mm after adjustment for height) and significantly greater in both genotypes than in AA controls (SS/AA difference 9.2 mm, SC/AA difference 5.0 mm after adjustment for height). Examination of relationships between renal length and some hematological indices (hemoglobin, fetal hemoglobin, reticulocyte counts, alpha thalassemia status) in SS or SC disease showed only a significant negative correlation with hemoglobin and positive correlation with reticulocyte count in SS disease. Further analysis suggested that the stronger relationship was between renal length and high reticulocyte count. The mechanism of renal enlargement is unknown although glomerular hypertrophy and increased renal blood volume are likely contributors.     

Cerebellar deficient folia (cdf): a new mutation on mouse chromosome 6

OBJECTIVE: To discuss the case of an 8-yr-old boy with an aneurysmal bone cyst of the right proximal humerus, including the features imaged on plain film radiography, computed tomography (CT), magnetic resonance imaging (MRI), including spin echo and fast field echo imaging. CLINICAL FEATURES: The patient suffered for 1 yr from intermittent but progressive pain in his right upper arm and shoulder area. There was no history of trauma or known systemic disease. There was decreased range of motion in abduction of the glenohumeral joint and pain on focal pressure along the deltoid muscle. A complete imaging evaluation consisting of plain film radiography, CT and MRI was performed, which revealed the classical imaging features of an aneurysmal bone cyst. An additional cystic lesion was detected by the MRI that was not appreciated on the plain films or CT. INTERVENTION AND OUTCOME: The patient was referred for biopsy to confirm the preliminary diagnosis of aneurysmal bone cyst. No treatment was instituted. CONCLUSION: Evaluation of aneurysmal bone cyst may be completed with CT scanning and more specifically with MRI MRI coronal T2, weighted images are advantageous for visualization of the main cystic lesion and any additional cysts. Fast field echo images show a better contrast between the cyst and bone marrow with extension of the cyst into the epiphysis as evident in this case. Follow-up studies revealed complete healing of the cyst with only residual densities in the humeral metaphyseal area.