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We present 60 years of Δ14CO2 measurements from Wellington, New Zealand (41° S, 175° E). The record has been extended and fully revised. New measurements have been used to evaluate the existing record and to replace original measurements where warranted. This is the earliest direct atmospheric Δ14CO2 record and records the rise of the 14C bomb spike and the subsequent decline in Δ14CO2 as bomb 14C moved throughout the carbon cycle and increasing fossil fuel CO2 emissions further decreased atmospheric Δ14CO2. The initially large seasonal cycle in the 1960s reduces in amplitude and eventually reverses in phase, resulting in a small seasonal cycle of about 2 ‰ in the 2000s. The seasonal cycle at Wellington is dominated by the seasonality of cross-tropopause transport and differs slightly from that at Cape Grim, Australia, which is influenced by anthropogenic sources in winter. Δ14CO2 at Cape Grim and Wellington show very similar trends, with significant differences only during periods of known measurement uncertainty. In contrast, similar clean-air sites in the Northern Hemisphere show a higher and earlier bomb 14C peak, consistent with a 1.4-year interhemispheric exchange time. From the 1970s until the early 2000s, the Northern and Southern Hemisphere Δ14CO2 were quite similar, apparently due to the balance of 14C-free fossil fuel CO2 emissions in the north and 14C-depleted ocean upwelling in the south. The Southern Hemisphere sites have shown a consistent and marked elevation above the Northern Hemisphere sites since the early 2000s, which is most likely due to reduced upwelling of 14C-depleted and carbon-rich deep waters in the Southern Ocean, although an underestimate of fossil fuel CO2 emissions or changes in biospheric exchange are also possible explanations. This developing Δ14CO2 interhemispheric gradient is consistent with recent studies that indicate a reinvigorated Southern Ocean carbon sink since the mid-2000s and suggests that the upwelling of deep waters plays an important role in this change.

Hepatocyte transplantation is restricted by the impaired ability of hepatocytes to engraft and survive in the damaged liver. Understanding the mechanisms that control this process will permit the development of strategies to improve engraftment. We studied changes in liver matrix during acute injury and delineated the mechanisms that perturb the successful adhesion and engraftment of hepatocytes. Collagen IV expression was increased in sinusoidal endothelium and portal tracts of fulminant hepatic failure explants, whereas there were minimal changes in the expression of fibronectin, tenascin, and laminin. Using an in vitro model of cellular adhesion, hepatocytes were cultured on collagen-coated plates and exposed to serum from patients with liver injury to ascertain their subsequent adhesion and survival. There was a rapid, temporally progressive decrease in the adhesive properties of hepatocytes exposed to such serum that occurred within 4 hours of exposure. Loss of activity of the beta1-integrin receptor, which controls adhesion to collagen, was seen to precede this loss of adhesive ability. Addition of the beta1-integrin activating antibody (TS2/16) to cells cultured with liver injury serum significantly increased their adhesion to collagen, and prevented significant apoptosis. In conclusion, we have identified an important mechanism that underpins the failure of infused hepatocytes to engraft and survive in liver injury. Pretreating cells with an activating antibody can improve their engraftment and survival, indicating that serum from patients with liver injury exerts a defined nontoxic biological effect. This finding has important implications in the future of cellular transplantation for liver and other organ diseases., (Copyright 2004 American Association for the Study of Liver Diseases)

Purpose: New nitric oxide (NO) donating nonsteroidal anti-inflammatory drugs (NSAIDs) have been synthesized to counteract the side effects of conventional NSAIDs. Mounting evidence suggests that NSAIDs may have a possible chemopreventative/therapeutic role in prostate cancer. NO is a powerful biological messenger with multiple cellular effects. We established the effects of 2 of these new drugs in prostate cell systems., Materials and Methods: We studied the effects of NO-ibuprofen (NCX 2111) and NO-aspirin (NCX 4060) on hormone sensitive (LNCap) and insensitive (PC3) prostate cancer epithelial cell lines as well as primary cultures of prostatic stroma. Proliferation was measured using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazalium bromide) assay to examine proliferation. Subsequently flow cytometry, cell cycle analysis and TUNEL staining were used to look for apoptosis. Caspase-3 expression was also examined in treated cell types., Results: NCX 2111 and NCX 4060 were found to be potent inhibitors of proliferation in a dose dependent fashion. The 2 drugs induced apoptosis, as seen by flow cytometry, cell cycle analysis and TUNEL staining, at doses between 10 and 100 microM. These NO-NSAIDs increased caspase-3 expression. NCX 4060 was more effective at lower concentrations (10 microM) but each compound was much more potent than conventional ibuprofen and aspirin at inducing apoptosis and inhibiting proliferation., Conclusions: NO-NSAIDs are potent antiproliferative pro-apoptotic compounds in prostate cell systems. This pro-apoptotic effect is mediated via caspase-3 and it is independent of the type of prostate cell used. These findings have ramifications for the use of these new drugs in prostate cancer chemoprevention or treatment.

Sphingolipids are emerging as important regulators of mammalian cell biology. In this study, the contents of six separate preparations of human omental mesothelial cells in vitro were examined for free sphingosine and sphinganine, and for the total levels of these sphingoid bases in ceramide-containing sphingolipids. Two high-performance liquid chromatography (HPLC) methods for determination of sphingoid base levels in cultured cells were compared. The rapid-HPLC method was found to yield the highest recovery of internal standard. Mesothelial cells initially isolated by collagenase digestion of the omentum were found to have higher free- and total-sphingoid base levels than cells isolated by trypsin-EDTA digestion. Use of sphingoid base levels to gain insights into the status of cellular nutrition, inflammation, programmed cell death, exposure to microbial toxins, cytokines, and growth factors within the peritoneum will require a systematic description of sphingolipids in normal, diseased, and dialyzed mesothelium.

In recent years it has become clear that the mesothelium plays a prominent homeostatic role in the peritoneum, and can be profoundly altered in disease and during peritoneal dialysis. The cell-surface phenotype of the mesothelial cell has not been thoroughly investigated. This study begins to identify cell surface molecules which may be important in mesothelial functions such as adhesion and interaction with cells of the immune system. The expression of adhesion structures on mesothelial cells such as CD44, the beta integrin chain CD29, the beta 3 integrin chain CD61 and alpha chains CD49 alpha (alpha 1), CD49b (alpha 2), CD49c (alpha 3), CD49e (alpha 5), and CD51 (alpha v) is described. In addition, a wide range of novel molecules including CD90, CD105, CD140b, CD142, CD147, CD151, CD157, CD165, and CD166 are identified. The role and function of such molecules in mesothelial biology and their significance for peritoneal dialysis is discussed.

6-Keto-PGF1 alpha, PGF2 alpha and PGE2 production by homogenates of aorta was unaffected by age, sex or smoking habits. Homogenates of saphenous vein from women aged 51-60 years produced greater and smaller amounts of 6-keto- PGF1 alpha and PGF2 alpha, respectively, than from women aged 41-50 and 61-70 years. In the 41-50 and 61-70 age groups, the amounts of 6-keto-PGF1 alpha and PGF2 alpha produced by homogenates of saphenous vein were smaller and greater, respectively, in women than in men. Cigarette smoking had no effect on PG production by homogenates of female saphenous vein. 6-Keto-PGF1 alpha production by homogenates of male saphenous vein was 20% lower in smokers and ex-smokers than in non-smokers, although this reduction was statistically significant only for ex-smokers. The amounts of PGE2 and PGF2 alpha produced by homogenates of male saphenous vein were smaller in smokers and ex-smokers, respectively, than in non-smokers. In spite of these changes in PG production by homogenates of saphenous vein, the basal outputs of PGs, particularly of 6-keto-PGF1 alpha, from the saphenous vein were little affected by age, sex or smoking habits.

Cimetidine infusion (100 mg h-1) reduced the acid secretory response to insulin infusion (0.03 units Kg-1h-1) when compared to paired control tests in 6 healthy volunteers. There was no significant difference between cimetidine and control tests in terms of pepsin output or serum gastrin concentrations. Cimetidine also reduced the acid secretory response when administered after 90 minutes of insulin had established a secretory response in extended tests in 3 additional volunteers. Cimetidine may have therapeutic potential in the peptic ulcer diathesis.

Extravascular lung water (EVLW) has been measured by a non-invasive technique using 123I-antipyrine and 113Indiumm-transferrin, as diffusible and non-diffusible indicators, and a gamma-camera computer system. Group A patients were normal radiologically and clinically. Group B patients were radiologically normal, clinically normal but were previously in heart failure and are currently on diuretics. Group C patients were radiologically normal, currently on diuretics with signs of pulmonary oedema. EVLW per unit blood flow and per unit blood volume were normal in groups A and B but raised in Group C patients. The peak height to equilibrium ratio of the 123I-antipyrine first pass curve was itself a useful discriminator in minimal pulmonary oedema.