Attribution of net carbon change by disturbance type across forest lands of the conterminous United States.

BACKGROUND: Locating terrestrial sources and sinks of carbon (C) will be critical to developing strategies that contribute to the climate change mitigation goals of the Paris Agreement. Here we present spatially resolved estimates of net C change across United States (US) forest lands between 2006 and 2010 and attribute them to natural and anthropogenic processes. RESULTS: Forests in the conterminous US sequestered -460 ± 48 Tg C year-1, while C losses from disturbance averaged 191 ± 10 Tg C year-1. Combining estimates of net C losses and gains results in net carbon change of -269 ± 49 Tg C year-1. New forests gained -8 ± 1 Tg C year-1, while deforestation resulted in losses of 6 ± 1 Tg C year-1. Forest land remaining forest land lost 185 ± 10 Tg C year-1 to various disturbances; these losses were compensated by net carbon gains of -452 ± 48 Tg C year-1. C loss in the southern US was highest (105 ± 6 Tg C year-1) with the highest fractional contributions from harvest (92%) and wind (5%). C loss in the western US (44 ± 3 Tg C year-1) was due predominantly to harvest (66%), fire (15%), and insect damage (13%). The northern US had the lowest C loss (41 ± 2 Tg C year-1) with the most significant proportional contributions from harvest (86%), insect damage (9%), and conversion (3%). Taken together, these disturbances reduced the estimated potential C sink of US forests by 42%. CONCLUSION: The framework presented here allows for the integration of ground and space observations to more fully inform US forest C policy and monitoring efforts.

Foreign body-induced changes in the reticular contraction pattern of sheep observed with M-mode ultrasonography.

In the pre-experimental period of a clinical trial, an apparently clinically healthy sheep fitted with ruminal and abomasal cannulas showed changes in the reticular contraction pattern visualized in M-mode ultrasonogram. Radiographic examination revealed a blunt metal screw in its reticulum. By the time change in the reticular motility through the ultrasound examination was detected, the animal had still not expressed any behavioral changes. A description of the clinical case, follow-up of the findings and laboratory data, like white blood cell count, serum pepsinogen and fibrinogen concentrations, were presented. The foreign body was removed through the ruminal cannula and reticular contraction tended to normal. An association of the contraction pattern with measured clinical data was possible, leading to the conclusion that use of M-mode ultrasonography has a potential application in similar clinical situations.

Patellar instability following experimental medial patellar desmotomy in horses.

A controlled study was designed in order to evaluate the effects of medial patellar desmotomy (MPD), combined with exercise restriction, on clinically and radiographically normal femoropatellar joints, and to identify the patellar instability by radiographic examination. MPD was performed on the right hind limb and the horses were rested for 120 days. Both hind limbs were radiographed before surgery and at 15, 30, 60, 90, and 120 days after MPD, obtaining lateromedial, flexed lateromedial, caudocranial and cranioproximal-craniodistal (skyline) views. The femorotibial and femoropatellar angles were assessed on the lateromedial views, and the distance between the medial and lateral cortex of the femur, and the distance between the medial cortex of the femur and the lateral border of the patella were evaluated in the caudocranial views. An increase in the angle between the proximal articular surface of the patella and the cranial distal surface of the femur along with enthesophyte formation and lateral deviation of the patella were found on the radiographs of the right stifles after MPD. Therefore, MPD leads to patellar instability, which can be demonstrated by the radiographic changes. The 120 days rest did not prevent the lesions caused by postsurgical patellar instability.

Rapid mobilization of intracellularly stored RANTES in response to interferon-gamma in human eosinophils.

The CC chemokine RANTES is synthesized, stored, and upregulated in response to interferon-gamma (IFN-gamma) in human peripheral blood eosinophils. In this report, we propose that RANTES is rapidly mobilized from eosinophil crystalloid granules during agonist-induced degranulation. We stimulated purified eosinophils (>99%) from atopic asthmatics with 500 U/mL IFN-gamma to analyze the kinetics of mobilization and release of RANTES (0 to 240 minutes). We used subcellular fractionation, immunogold analysis, two-color confocal laser scanning microscopy (CLSM), and enzyme-linked immunosorbent assay (ELISA) to trace the movement of eosinophil-derived RANTES from intracellular stores to release. RANTES was rapidly mobilized (10 minutes) and released after 120 minutes of stimulation (80 +/- 15 pg/mL per 2 x 10(6) cells). RANTES appeared to be stored in at least two intracellular compartments: the matrix of crystalloid granules, detected by major basic protein and eosinophil peroxidase activities, and a specialized small secretory vesicle present in light membrane fractions. The extragranular RANTES was mobilized more rapidly than that of crystalloid granules during IFN-gamma stimulation. This effect was not observed in eosinophils treated with IFN-alpha, interleukin-3 (IL-3), IL-5, granulocyte-macrophage colony-stimulating factor (GM-CSF), or genistein followed by IFN-gamma. Our findings suggest that RANTES may be mobilized and released by piecemeal degranulation upon stimulation, involving transport through a putative pool of small secretory vesicles.

Intracellular localization of interleukin-6 in eosinophils from atopic asthmatics and effects of interferon gamma.

Eosinophils, prominent cells in asthmatic inflammation, have been shown to synthesize, store, and release an array of up to 18 cytokines and growth factors, including interleukin-6 (IL-6). In this report, we show that IL-6 immunofluorescence localizes to the matrix of the crystalloid granule in peripheral blood eosinophils from atopic asthmatics using confocal laser scanning microscopy (CLSM). Granule localization of IL-6 was confirmed using dot-blot analysis and enzyme-linked immunosorbent assay (ELISA) on subcellular fractions of highly purified eosinophils produced from density centrifugation across a 0% to 45% Nycodenz gradient. IL-6 was found to coelute with eosinophil crystalloid granule marker proteins, including eosinophil peroxidase (EPO), major basic protein (MBP), arylsulfatase B, and beta-hexosaminidase. Immunoreactivity to IL-6 colocalized with granule-associated IL-2 and IL-5 in subfractionated eosinophils. We also made the novel and compelling observation that interferon gamma (IFNgamma), a Th1-type cytokine, stimulated an early elevation in eosinophil IL-6 immunoreactivity. A 2.5-fold enhancement of IL-6 immunoreactivity in eosinophil granules was observed within 10 minutes of IFNgamma treatment (500 U/mL), as determined by subcellular fractionation and CLSM. These findings suggest that IFNgamma has short-term effects on human eosinophil function and imply that a physiologic role exists for Th1-type cytokine modulation of Th2-type responses in these cells.

Effects of pinealectomy on reproduction in the Syrian hamster mutant anophthalmic white (Wh).

The gene Wh, causing anophthalmia in the Syrian hamster, Mesocricetus auratus, is a pleiotropic gene affecting eye development, pigmentation, hearing, and reproduction. Male hamsters homozygous for this gene are usually sterile. Since both Wh and the pineal organ are known to suppress reproductive function, the objective of this study was twofold: (1) to determine whether Wh, by itself, influences testicular differentiation; and (2) to determine whether removal of the pineal gland will restore fertility to both experimentally blinded (B), genetically normal [wh/wh(B)] hamsters and mutant, eyeless (Wh/Wh) hamsters. Accordingly, one testis from each of ten wh/wh(B) and ten Wh/Wh hamsters at approximately 60 days of age was removed, and these testes were compared at the gross and light microscopic level. Since all testes were identical at 60 days of age and contained normal differentiating germ cells, the gene Wh does not appear to affect initial testicular differentiation. Testicular tissues from at least ten wh/wh, wh/wh(B), heterozygous (Wh/wh), and Wh/Wh hamsters, at 135 days of age, were also compared. Testes from all wh/wh(B), and 70% of the Wh/Wh hamsters were hypoplasic and aspermic. Approximately 30% of the testes from Wh/Wh hamsters contained some seminiferous tubules with normal sperm present. Pinealectomy fully restored adult testicular size and morphology in all wh/wh(B) and Wh/Wh hamsters. Thus, it was demonstrated that the atrophy of testes from Wh/Wh individuals is a pineal-mediated phenomenon due to failure of eye development and the subsequent lack of a functional visual pathway. Testes from Wh/Wh hamsters appear to be completely competent to respond to the normal, antigonadotrophic effects of the pineal.