Orbital venous anomalies. A long-standing dilemma

Chronic pancreas transplant rejection with enteric exocrine drainage can lead to significant long-term complications. We report a case of a 47-year-old male insulin-dependent diabetic who survived the complications of peripancreatic abscess, enterocutaneous fistula, and arterioenteric fistula related to pancreas transplantation. To avoid these long-term complications, we now recommend elective removal of nonfunctioning, enterically drained pancreas allografts.     

Humoral (antibody-mediated) rejection in lung transplantation

To confirm the existence and characterize the pathologic features of humoral (antibody-mediated) lung rejection, we prospectively studied 55 lung transplant recipients (24 male [44%] and 31 female [56%], age range 14 to 69 years [mean 45]). The time between transplantation and biopsy ranged from 2 to 1546 days (mean 274). We performed direct immunofluorescence with C3, immunoglobulin M, and immunoglobulin G antibodies on frozen sections of 106 transbronchial biopsies and one wedge biopsy and compared the results with 13 explanted lungs, one donor lung, and two controls. The histologic diagnoses of these 107 biopsies included acute cellular rejection (62, 58% [minimal 23, mild 33, moderate 5, and severe 1]), chronic rejection (eight, 7%), chronic vascular rejection (two, 2%), acute vasculitis (five, 5%), cytomegalovirus pneumonitis (two, 2%), acute pneumonia (two, 2%), acute organizing pneumonia (two, 2%), diffuse alveolar damage (one, 1%), no evidence of rejection or infection (30, 28%), lipoid pneumonia (one, 1%), and inadequate for histologic diagnosis (one, 1%). Eighty-nine of 106 (84%) transbronchial biopsies, the wedge biopsy, and control lungs were satisfactory for direct immunofluorescence, because each contained alveolate lung parenchyma and arterioles or venules. There was no demonstrable immunofluorescence in the wall of the blood vessels or in the lung parenchyma in any case. We conclude that (1) transbronchial biopsies and wedge biopsies provide adequate material to evaluate humoral rejection, and (2) in spite of the large population studied, the satisfactory material obtained, and the wide range of histologic diagnoses, we could not demonstrate the occurrence of humoral rejection in the lung.     

Pheromone of the male flesh fly,Sarcophaga bullata

Hexanal, isolated from a whole animal extract of the flesh fly,Sarcophaga bullata, attracts over 65% of the females tested with no apparent effect on males.     

A Flow Boiling Microchannel Evaporator Plate for Fuel Cell Thermal Management

In order to provide a high-power density thermal management system for PEM fuel cell applications, a flow boiling microchannel evaporator plate has been developed that operates in a closed loop two-phase thermosyphon. The flow is passively driven by gravity, and the flow rate initially increases with increasing evaporation rate and then decreases after reaching a peak flow rate. A microchannel plate has been fabricated with 56 square channels that have a 1 mm × 1 mm cross-section and are 115 mm long. The working fluid, HFE-7100, has been chosen due to its favorable saturation temperature at one atmosphere. Experiments have been conducted with the heat flux as the control variable. Measurements of mass flow rate, temperature field, and pressure drop have been made. The flow regimes are predominately bubbly and slug. The maximum heat flux observed, 32 kW/m², is an order of magnitude greater than that required in current fuel cells and is limited by a Ledinegg instability. Two-phase thermal hydraulic models give a reasonable prediction for the mass flow rates and wall temperatures using standard flow boiling correlations. This paper will thoroughly describe the performance of the two-phase thermal management system over a wide range of operating conditions.     

The role of second-intention healing in periocular reconstruction

Second-intention healing is a time-honored method of wound management. Its role in periocular reconstruction, however, is currently controversial. The objectives of this thesis are threefold: to evaluate carefully the outcomes in a cohort of patients treated by this technique, to provide a comprehensive review of published reports, and to formulate recommendations and guidelines for appropriate application in selected patients. Eyelid and periorbital defects after excision of periocular tumors were allowed to heal by second intention in 59 patients. The locations of the wounds were the medial canthus (n = 32), lower eyelid (n = 20), upper eyelid, (n = 4), glabella (n = 2), and nasojugal fold (n = 1). Five excised areas involved the eyelid margin, and in three patients the defect included the canalicular system. The size of the defects ranged from 3 x 3 mm to 22 x 27 mm. The average duration of follow-up was 19 months (range, 6 months to 8 years). The functional and cosmetic results were satisfactory in 49 patients (83%). Complications occurred in 10 patients and included ectropion, medial canthal webbing, trichiasis, eyelid notching, and hypertrophic scarring. Only two patients, however, required secondary repair. Healing by second intention is a safe, effective, and inexpensive alternative to surgical reconstruction after tumor excision in selected patients.     

Characterization of emissions of dioxins and furans from ethylene dichloride (EDC), vinyl chloride (VCM) and polyvinylchloride (PVC) manufacturing facilities in the United States. I. Resin, treated wastewater, and ethylene dichloride

Under the auspices of its Dioxin Characterization Program, members of The Vinyl Institute (VI), have analyzed for potential polychlorinated dibenzodioxin/furan (PCDD/F) concentrations in polyvinylchloride (PVC) resins, treated wastewater effluent and ethylene dichloride (EDC) product at EDC, vinyl chloride monomer (VCM) and PVC manufacturing facilities in the U.S. and Canada. No 2,3,7,8-tetrachlorodibenzodioxin (TCDD) was detected in any sample analyzed under the program to date. Trace concentrations (low pg/g) of PCDD/F were detected in only a few samples of PVC resins and EDC product. Treated wastewater contained low ppq concentrations of PCDD/F. All concentrations are expressed as Toxic Equivalents (TEQ). Extrapolation of these data shows that the contribution of EDC/VCM/PVC manufacturing via these media constitutes substantially less than 1 percent of the estimated annual U.S. dioxin releases to the environment.     

Disentangling the relationships between plant pigments and the photochemical reflectance index reveals a new approach for remote estimation of carotenoid content

The Photochemical Reflectance Index (PRI) is used as an indicator of leaf and plant canopy photosynthetic efficiency. However, the photosynthetic efficiency-PRI relationship has been shown to be inconsistent over time, likely due to changes in foliar pigment content.We measured reflectance spectra and biochemical properties from 24 leaves of two deciduous tree species and acquired pigment and reflectance data from the Leaf Optical Properties EXperiment database for an additional nine species. These data were used as inputs for the PROSPECT-5 leaf optical model. We found measurements of PRI to be significantly (p < 0.05) correlated with chlorophyll content, carotenoid content, and the carotenoid/chlorophyll ratio. However, only the PRI-carotenoid/chlorophyll ratio relationship was consistent across all analyses. Two predictive equations were derived from PROSPECT-5 simulations: a curvilinear PRI model (PRI(clm)) predicted the carotenoid/chlorophyll ratio (r² = 0.99), and a linear model using the chlorophyll index (CI(lm)) predicted chlorophyll content (r² = 0.98). Multiplying PRI(clm) with CI(lm) canceled the influence of chlorophyll content on PRI(clm) and thus allowed for prediction of carotenoid content from 11 deciduous tree species (r² = 0.83). Our results confirm that the PRI is significantly influenced by chlorophyll and carotenoid pools and demonstrate a new approach for non-destructive estimation of leaf carotenoid content using the PRI. Because variation in foliar physiological status is known to relate to leaf carotenoid content and the carotenoid/chlorophyll ratio, convolving the PRI with a chlorophyll index is likely to be useful for understanding the photosynthetic performance of deciduous vegetation across a wide range of temporal periods, ranging from daily to seasonal time scales.