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Abstract. We analyse the development of a radiation fog event and its gradual transition from optically thin fog in a stable boundary layer to well-mixed optically-thick fog. Comparison of observations and a detailed large-eddy simulation demonstrate that aerosol growth and activation is the key process in determining the onset of adiabatic fog. Weak turbulence and low supersaturations lead to the growth of aerosol particles which can significantly affect the visibility, but do not significantly interact with the long-wave radiation, allowing the atmosphere to remain stable. Only when a substantial fraction of the aerosol 5 become activated into cloud droplets can the fog interact with the radiation, becoming optically thick and well-mixed. Modifications to the parametrization of cloud droplet numbers in fog, resulting in lower and more realistic concentrations, are shown to give significant improvements to an NWP model, which initially struggled to accurately simulate the transition. Finally, consequences of this work for common aerosol activation parametrizations used in climate models are discussed, demonstrating that many schemes are reliant on an artificial minimum value when activating aerosol in fog, and adjustment of this minimum 10 can significantly affect the sensitivity of the climate system to aerosol radiative forcing.

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Purpose To test whether memantine can prevent methotrexate-induced cognitive deficits in a preclinical model. Experimental Design After noting that methotrexate exposure induces prolonged elevations of the glutamate analog homocysteic acid (HCA) within cerebrospinal fluid, we tested whether intrathecal injection of HCA would produce memory deficits similar to those observed after intrathecal methotrexate. We then tested whether memantine, an antagonist of the N-methyl-D-aspartate (NMDA) subclass of glutamate receptors, could protect animals treated with clinically relevant doses of intrathecal methotrexate against developing memory deficits. Finally, we asked whether memantine affected this pathway beyond inhibiting the NMDA receptor by altering expression of the NMDA receptor or affecting concentrations of HCA or glutamate within the central nervous system. Results Four intrathecal doses of methotrexate induced deficits in spatial memory, persisting at least one month following the final injection. Intrathecal HCA was sufficient to reproduce this deficit. Concurrent administration of memantine during the period of methotrexate exposure was protective, decreasing the incidence of methotrexate-induced spatial memory deficits from 56% to 20% (P < 0.05). Memantine neither altered expression of NMDA receptors within the hippocampus nor blunted the methotrexate-induced increases in glutamate or HCA. Conclusions Excitotoxic glutamate analogs including HCA contribute to cognitive deficits observed after intrathecal methotrexate. Memantine, an NMDA receptor antagonist, reduces the incidence of cognitive deficits in rats treated with intrathecal methotrexate, and may therefore benefit patients with cancer receiving similar treatment.

Objective To assess the prognostic significance of presentation serum albumin, clinical stage and CA125 levels in ovarian cancer. Design Retrospective analysis of data using a Cox proportional hazards model. Setting A district general hospital oncology unit. Subject One hundred and fourteen consecutive patients with epithelial ovarian cancer. Interventions Cytotoxic chemotherapy and surgery. Main outcome measure Survival. Results A linear increase in risk was observed with high log CA125 (P < 0.0001) and with low albumin (P < 0.0001). In late stage patients (III and IV) albumin is the best predictor of survival (P= 0.0006). The presence of ascites, blood transfusion, type of surgery or chemotherapy did not improve the predictive model. Conclusions CA125 and albumin can be used to identify prognostic subgroups independently of stage. Albumin alone can also be used as a predictor of survival. A simple classification of patients into three groups based on serum albumin of 41 g/l or more, 35 to 40 g/l and 34 g/l or less provides a clear separation of survival curves in the present group of patients.

Summary Serum levels of mucin-like carcinoma associated antigen (MCA) were

Over a 2-year period, more than 1700 abdominal ultrasound scans were performed which included a search for bowel disease in the scanning routine. Features consistent with a primary colonic neoplasm were reported in 35 patients. In 14 patients, ultrasound indicated the possibility of a colonic neoplasm in the absence of a clinically palpable mass. An intraabdominal mass was confirmed in 12 patients (86%), and was a primary colonic neoplasm in 11 patients (79%). In one patient a metastatic malignant mass had been misinterpreted as arising from the colon. In two patients no lesion could be demonstrated to account for the ultrasonographic abnormality. In a further 21 patients in which an abdominal mass had been evident on clinical examination, ultrasound was performed for further elucidation and indicated the mass to be arising from the colon. In this group, a primary colonic neoplasm was the cause in 11 patients (52%), while other primary or metastatic malignancy was found in six patients (29%) and benign disease in four patients (19%). We conclude that ultrasound is a useful primary diagnostic technique for colonic neoplasms, with a predictive value of 79% in detecting clinically non-palpable lesions. In our experience, false positive results due to scanning artefacts are rare. We consider that examination of the bowel is a worthwhile addition to the routine scan in patients with non-specific abdominal complaints.

The present report of four cases highlights the potential for focal organizing pneumonia (FOP) to masquerade as a small peripheral lung adenocarcinoma on CT scans. Both entities may present the CT appearance of a peripheral spiculated lung nodule, often with an air bronchogram. A history suggestive of an infectious aetiology and the presence of other foci of inflammatory change on CT scan may be helpful clues to the diagnosis of FOP. Because FOP is comparatively rare, surgical excision will usually be required to exclude malignancy. In some cases, however, particularly after a negative percutaneous biopsy, conservative management with a follow-up CT scan at 3-4 weeks may be an alternative to immediate surgical intervention.