Thirty-seven patients with external gastrointestinal fistulas were treated with a combination of total parenteral nutrition (TPN) and somatostatin (ST). There was a significant fall in fistula output within the first day of treatment (p less than 0.001). On the first day of combined therapy, the reduction of fistula output was 70%, and in 68% of the cases, the fistula output fell to less than 50% of the initial level. Spontaneous closure was observed in 82% of the cases, and the time taken to close the fistula ranged between 1 and 14 days of starting therapy [5.4 +/- 0.7 days (mean +/- SEM)]. The response to TPN-ST treatment occurred, irrespective of age and sex of patients, duration and daily output of the fistulas before ST use, and their location in the gastrointestinal tract. Infection of fistula output was a factor of adverse prognosis. In all cases, and in the absence of mechanical obstacles, treatment that combines TPN and ST could be tried and continued up to 14 days in cases in which the fistula output falls more than 50% on the first day of treatment.
The effect of progesterone on 14C-testosterone metabolism and on 14C-lipid synthesis was studied in two animal sebaceous gland models, hamster flank organ and rat ear skin. Unilateral topical application of progesterone to the female hamster flank organ topically treated with testosterone propionate resulted in localized inhibition of both in vitro 14C-lipogenesis and in vitro conversion of 14C-testosterone to 5 alpha-reduced radio-metabolites. Topical progesterone did not inhibit in vitro 14C-lipogenesis in the male hamster flank organ. Progesterone added in vitro inhibited 14-C-lipogenesis and 14C-testosterone metabolism in male rat ear sebaceous glands. These results lend support to the hypothesis that inhibition of sebaceous gland lipogenesis by progesterone is a consequence of its inhibitory effect on testosterone metabolism. Such a rationale provides a valid explanation for the clinical findings with progesterone reported by other investigators.
Comparative study of experimental and theoretical curves obtained by plotting transepidermal water loss against stratum corneum thickness in man, shows that every layer in the stratum corneum acts as part of the epidermal barrier to water loss. Another function of the stratum corneum is to decrease the cutaneous penetration of topical corticosteroids like difluprednate and to modify their bioavailability (‘corticosteroid reservoir’) Our data suggest that variations in stratum corneum thickness between subjects explain variation of transepidermal water loss and sensitivity difluprednate, as there is a close relationship between these two parameters. It is then conceivable that the phototype has clinical implications if there really exists a relationship between phototype, stratum corneum thickness and sensitivity to steroids.
Phototoxicity of bergamot oil in solar simulating radiation (SSR ≥ 290 nm) and in long ultraviolet radiation (LUV ≥ 320 nm) has been compared by studying photoaugmentation of erythema in the guinea pig after 24 h and pigmentary photoaugmentation in man on the 8th day. The results show that a close relationship exists between guinea pig and human responses, with both radiations used, and that man seems to be slightly more sensitive to phototoxic effects of bergamot oil than the guinea pig. This difference of sensitivity necessarily implies the participation of U VA (320–400 nm) in the phototoxic reaction of bergamot oil with solar radiation. This UVA participation is particularly obvious in the guinea pig; in man, the results are less clear and a certain synergy of UVB rays (290–320 nm) may be involved in the phototoxic UVA-induced reaction of bergamot oil. Despite these slight differences, the erythematous reaction in the guinea pig appears to be a remarkable experimental model to show out potential phototoxic reactions of products containing psoralens in man.
SynopsisAprks avoir rappelk brikvement lc spectre d'action biologique du rayonnement ultraviolet du soleil sur la peau normale et les donndes thkoriques de protection qui en dicoulent, le caract& privisionnel de diff6rentes mkthodes d'6tude in vitro et in viuo des antisolaires est comment6 1 partir dc rksultats obtcnus en lahoratoire sur differents principes actifs (PABA, F:usolcx 4360, Giv Tan I:), ct prdparations cosm6tiques du commerce.Les mdthodes in vitro, basks sur I'absorption dans 1'UV des produits, aboutissent i une protection sur6valude et dans ces conditions B une extrapolation trds al6atoirc du pouvoir de protection.La m6thode utilis6c in vivo (ddterniination classique d'un indice de protection) souligne, dans le cadre de la prkdiction, le choix de la qualite d'absorption du fitre, de la source UV utilisbe, mais aussi de nombreus autres facteurs agissant sur la protection. Dans ces conditions, les rdsultats obtcnus chez Ie cobaye et l'homme avcc des irradiations simulant le spectre solaire, niontrent alors unc concordance satisfaisante pour les principes actifs 6tudibs. Ces observations sont ensuite commentkes par comparaison i d'autres travaux publiks faisant mention d'autre source d'irradiation (spectre de raies) et de methode de detection (therrnombtriquc cn particulier). Predictive nature of laboratory methods in sunscreen studies Summary After a brief summary of biological actions of UV radiation in sunlight on normal skin and the resulting theoretical claims of protcction, the different in viiro and i n . viuo methods of studies of sunscreens arc revic~ed. Laboratory results are given for different active substances: paraamino benzoic acid (PABA), 2 hydro4methoxy benzophenone and 2 ethoxy ethyl p-niethoxycinnamate, and a number of commercial preparations.Most in viiro methods are spectrophotonietric and dependence on them seems logical since the efficiency of sunscreens depends on a selective absorption of UV. The calculated sun protection factor (SPF) based on them is, however, always exaggerated. They also do not takc into account product interactions with normal skin, thickness of applied f i l m , product resistance to water nor the synergistic action of UV-A on the erythematous reaction of UV-B. This renders these methods of limited value and their extrapolation to an SPF is hazardous. The in viuo determination of SPF (multiplication factor of the time of natural photoprotection) used is based on the comparison of W irradiated 0142-5463/82/0800-0115 $02.00 0 1982 International Journal of Cosmetic Science 115 116 J. Girard et al. skin protected and unprotected with the sunscreen product using an objective method of measurement of erythema.Comparison of results on man and guinea-pig using a solar simulation give good agreement for the three materials studied and refcrence is made to other irradiating spectra and methods of determination of erythema, notably thermometric.The method described appears to be readily extrapolable to man and conveniently and rapidly applicable to cosmetic formulati...
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