11␤-Hydroxysteroid dehydrogenase type 1 (11HSD1) regenerates cortisol from cortisone within adipose tissue and liver. 11HSD1 inhibitors may enhance insulin sensitivity in type 2 diabetes and be most efficacious in obesity when 11HSD1 is increased in subcutaneous adipose biopsies. We examined the regeneration of cortisol in vivo in obesity, and the effects of the 11HSD1 inhibitor carbenoxolone. We compared six lean and six obese men and performed a randomized, placebo-controlled crossover study of carbenoxolone in obese men. 11␤-Hydroxysteroid dehydrogenase type 1 (11HSD1) is a microsomal enzyme expressed in many tissues, including liver and adipose tissue (1). It catalyzes the regeneration of the active glucocorticoid cortisol from its inactive 11-keto metabolite cortisone. This intracellular generation of cortisol plays a key role in amplifying glucocorticoid receptor activation independently of the level of cortisol in the circulating plasma. Its potential importance is illustrated in animal models. Transgenic mice that overexpress 11HSD1 by approximately threefold selectively in adipocytes under the AP2 promoter/enhancer (2,3) develop about a twofold increase in intraadipose glucocorticoid levels despite no change in plasma levels, which are controlled by a compensatory fall in ACTH secretion. This results in central obesity together with hyperinsulinemia, hyperglycemia, hyperlipidemia, and hypertension. Mice with similar overexpression of 11HSD1 in liver under the ApoE promoter develop insulin resistance, dyslipidemia, and hypertension without obesity (4). Conversely, 11HSD1 knockout mice on a high-fat diet are protected from obesity, hyperglycemia, and dyslipidemia and redistribute fat to peripheral rather than central fat depots (5-7). Moreover, inbred rodent models of obesity and diabetes show tissue-specific dysregulation of 11HSD1 (2,8,9); most commonly, 11HSD1 is reduced in liver but increased in adipose tissue. These findings substantiate the hypothesis that increased intra-adipose glucocorticoid regeneration by 11HSD1 contributes to obesity and its metabolic complications.Whether increased 11HSD1 levels have a similar importance in human obesity and associated type 2 diabetes is controversial (10). The conventional measure of 11HSD1 is the ratio of urinary cortisol to cortisone metabolites, which is inconsistently altered in obesity (11-16) and diabetes (17)(18)(19). However, this ratio may be confounded by the activity of other enzymes (e.g., 11HSD type 2, 5␣-and 5␤-reductase) that differ in obesity, and is insensitive to the tissue-specific changes in 11HSD1 that have been observed in animals. Hepatic 11HSD1 has been assessed in humans by measuring the conversion of an oral dose of cortisone into cortisol in peripheral plasma after "first pass" metabolism, and is consistently reduced in obesity

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The application of membrane gas separation to CO2 capture from a coal gasification process is one potential solution to reduce greenhouse gas emissions. This review considers the potential for either H2-or CO2-selective membranes in an integrated gasification combined cycle (IGCC) process. In particular, the advantages and disadvantages of metallic, porous inorganic and polymeric membranes are considered. This analysis is extended to consider membrane technology as an enhancement to the water gas shift reaction, to drive the production of hydrogen above the thermodynamic limit. The review concludes with a brief overview of the economics of incorporating membrane gas separation into the IGCC process and gives an indication of the potential economic use of membrane gas separation technology in the IGCC process.

Currently, a large proportion of global fossil fuel emissions originate from large point sources such as power generation or industrial processes. This trend is expected to continue until the year 2030 and beyond. Carbon capture and storage (CCS), a straightforward and effective carbon reduction approach, will play a significant role in reducing emissions from these sources into the future if atmospheric carbon dioxide (CO 2 ) emissions are to be stabilized and global warming limited below a threshold of 2°C. This review provides an update on the status of large scale integrated CCS technologies using solvent absorption for CO 2 capture and provides an insight into the development of new solvents, including advanced amine solvents, amino acid salts, carbonate systems, aqueous ammonia, immiscible liquids and ionic liquids. These proposed new solvents aim to reduce the overall cost CO 2 capture by improving the CO 2 absorption rate, CO 2 capture capacity, thereby reducing equipment size and decreasing the energy required for solvent regeneration.

The prospect of a hormonal male contraceptive is no longer distant. Data on the potential impact of this improvement in contraceptive provision, however, is limited, particularly between different cultures. We have therefore carried out a multi-centre study to assess men's attitudes to proposed novel hormonal methods. Questionnaire-based structured interviews were administered to men in Edinburgh, Cape Town, Shanghai and Hong Kong. Approximately 450 men were interviewed in Edinburgh, Shanghai and Hong Kong, and a slightly larger group (n = 493) in Cape Town to give samples (n > 150) of black, coloured and white men. Knowledge of existing male and female methods of contraception was high in all centres and groups. The majority of men welcomed a new hormonal method of contraception, 44-83% stating that they would use a male contraceptive pill. Overall, a pill was more acceptable than an injectable form (most popularly given at 3-6 month intervals); long-acting implants were least so except in Shanghai. Familiarity with comparable female methods appeared to influence acceptability, for both oral and injectable methods. Hong Kong was the only centre where a male method (condom) was currently the most commonly used; men there appeared to rate the convenience of condoms highly while being least likely to think that they provided effective protection against pregnancy compared to other centres, and were least enthusiastic about novel male methods. The acceptability of potential male hormonal methods of contraception was high in some groups but showed wide variability, determining factors including cultural background and current contraceptive usage. These results suggest that the emerging emphasis that men should have greater involvement in family planning will be substantiated when appropriate contraceptive methods become available.

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A majority of children eventually ceased feeds successfully, but slow and failed weaning is more likely after age 5 years.