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Secondary Effects (secondary + effects)
Selected AbstractsDo "Off-Site" Adult Businesses Have Secondary Effects?LAW & POLICY, Issue 2 2009Empirical Evidence, Legal Doctrine, Social Theory Recent federal court decisions appear to limit the ability of cities to mitigate the ambient crime risks associated with adult entertainment businesses. In one instance, a court has assumed that criminological theories do not apply to "off-site" adult businesses. After developing the legal doctrine of secondary effects, we demonstrate that the prevailing criminological theory applies to all adult business models. To corroborate the theory, we report the results of a before/after quasi-experiment for an off-site adult business. When an off-site adult business opens, ambient crime risk doubles compared to a control area. As theory predicts, moreover, ambient victimization risk is most acute in night-time hours. The theoretical development and empirical results have obvious implications for the evolving legal doctrine of secondary effects. [source] Secondary effects induced by the colon carcinogen azoxymethane in BDIX rats,APMIS, Issue 6 2004MORTEN KOBÆK-LARSEN Azoxymethane (AOM) is claimed to be a colon-specific carcinogen. In our studies, AOM was administered to adult BDIX/OrlIco rats by four weekly subcutaneous injections of 15 mg/kg body weight each , two periods of 2 weeks of AOM treatment separated by a one-week break. This treatment schedule resulted in colon carcinomas with a high frequency (75,100%) and with a high reproducibility. However, some serious side effects are associated with this carcinogen treatment. In addition to the colorectal tumours, we found small intestinal tumours, hepatic lesions and a high frequency of mesenchymal renal tumours which increased with longer latency periods. The renal tumours were only found in female rats, and this indicates a possible relation to sex hormones. We therefore analyzed both male and female kidneys for the expression of estrogen and progesterone receptors by immunohistochemical methods. A positive nuclear reaction for estrogen receptor was present in most tumour cells in all tumours and occasionally in nuclei of entrapped tubular cells, but never in glomeruli. Normal appearing renal tissue from female rats showed no positive reaction, but in male rats a slight nuclear reaction was seen in tubuli in the peripheral part of the medulla. A similar pattern was seen for progesterone receptors, but less pronounced. No rats developed tumours in the external ear canal, which is in contrast to studies performed in other rat strains. This may therefore be strain related. In order to reduce the secondary effects of the induction of colon cancer by AOM, it is advisable to use male rats only and a maximum latency period of 32 weeks. [source] Angiokeratoma Circumscriptum Naeviforme: Successful Treatment with Carbon-Dioxide Laser VaporizationDERMATOLOGIC SURGERY, Issue 2 2005Jesús del Pozo MD Background Angiokeratoma circumscriptum naeviforme (ACN) is an unusual type of localized angiokeratoma that occurs more frequently in females and is usually located on the buttocks or thighs, showing a unilateral distribution. ACN usually causes large lesions, which may require laser ablation because they often are too extensive to perform surgical excision. Carbon-dioxide laser is a known alternative for treating angiokeratomas. Objective Report of two cases of ACN treated with carbon-dioxide laser vaporization. Patients and methods A 28-year-old woman with a hyperkeratotic, violaceus plaque on her left buttock and a 24-year-old woman with a similar lesion on her right buttock were treated with a carbon-dioxide laser. Two laser passes were performed on each lesion within a single session. Results A successful cosmetic aspect of treated areas was obtained, with minimal pigmentary or textural changes. After a 2-year follow-up in the first patient and a 6-month follow-up in the second patient, no recurrence of the lesions was observed. Conclusions Our results, obtaining relevant cosmetic improvement after a few sessions of treatment, with low morbidity and minimal secondary effects, suggest that continuous-wave carbon-dioxide laser vaporization is a safe and effective treatment for ACN. JESÚS DEL POZO, MD, AND EDUARDO FONSECA, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Loss of steroidogenic factor 1 alters cellular topography in the mouse ventromedial nucleus of the hypothalamusDEVELOPMENTAL NEUROBIOLOGY, Issue 4 2004Aline M. Davis Abstract Knockout (KO) mice lacking the orphan nuclear receptor steroidogenic factor 1 (SF-1) exhibit marked structural abnormalities of the ventromedial nucleus of the hypothalamus (VMH). In this study, we sought to determine the molecular mechanisms underlying the VMH abnormalities. To trace SF-1-expressing neurons, we used a SF-1/enhanced green fluorescent protein (eGFP) transgene. Although the total numbers of eGFP-positive cells in wild-type (WT) and SF-1 KO mice were indistinguishable, cells that normally localize precisely within the VMH were scattered more diffusely in adjacent regions in SF-1 KO mice. This abnormal distribution is likely due to the loss of SF-1 expression in VMH neurons rather than secondary effects of deficient steroidogenesis, as redistribution also was seen in mice with a CNS-specific KO of SF-1. Thus, the absence of SF-1 alters the distribution of cells that normally form the VMH within the mediobasal hypothalamus. Consistent with this model, the hypothalamic expression patterns of the transcription factors islet-1 and nkx2.1 also were displaced in SF-1 KO mice. Independent of gene expression, birthdate analyses further suggested that cells with earlier birthdates were affected more severely by the loss of SF-1 than were later born cells. We conclude that the absence of SF-1 causes major changes in cellular arrangement within and around the developing VMH that result from altered cell migration. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 424,436, 2004 [source] Antioxidant and antimutagenic effects of the crude foliar extract and the alkaloid brachycerine of Psychotria brachycerasENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 9 2007Naíla Cannes do Nascimento Abstract The monoterpene indole alkaloid brachycerine from Psychotria brachyceras has been shown to be induced by UV and to have in vitro antioxidant activity, indicating a possible protective role against the secondary effects of this radiation. In this work, we have studied the antioxidant properties of brachycerine and a crude foliar extract from P. brachyceras by using Saccharomyces cerevisiae strains proficient and deficient in antioxidant defenses. The mutagenic and antimutagenic potential of these substances were assayed in S.cerevisiae N123 strain in the presence and absence of H2O2. In addition, we tested the antioxidant capacity of brachycerine and a crude foliar extract from P. brachyceras on hydroxyl radicals (OH,) using the hypoxanthine/xanthine oxidase assay. The results show that brachycerine and the crude foliar extract of P. brachyceras have antioxidant and antimutagenic effects in yeast and probably this action is mainly due to the scavenging of OH, radicals. Environ. Mol. Mutagen., 2007. © 2007 Wiley-Liss, Inc. [source] Syntheses, Structures and Theoretical Investigations of 1,4,3,4,5,4 -Trithia-2,4,6,8,9-pentaazabicyclo[3.3.1]nona-1(9),2,3,5,7-pentaenesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 17 2003Carsten Knapp Abstract The syntheses of the title compounds RCN5S3 with electron-withdrawing aryl substituents [R = 2-FC6H4 (1m), 4-FC6H4 (1n), 2,6-F2C6H3 (1o), C6F5 (1p), 4-NCC6H4 (1q) and Cl3C (1r)] are described. The X-ray structures of 1n, 1o, 1q and 1r, together with those of Me2NCN5S3 (1b) and 4-CH3C6H4CN5S3 (1f), are reported. The experimentally determined dependence of the bond lengths on the substituents R within the bicyclic system RCN5S3 is well-reflected in the results of the theoretical calculations (RHF, MP2, B3LYP). The bonding model developed shows that acceptor substituents do not influence bonding within the bicycle. In the solid state, two fundamentally different primary interactions of the RCN5S3 molecules are observed; "stacking" and "dimerisation", which can be rationalised by electrostatic interactions between the CN5S3 units. However, secondary effects , the interactions between the R substituents , may be even more dominant. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Cutaneous leishmaniasis: successful treatment with itraconazoleINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 1 2006Javier Consigli MD Background, Leishmaniasis is a disease produced by several species of protozoa of the Leishmania genus. These protozoa are injected into the human bloodstream by sandflies. The symptomathology, either cutaneous, mucocutaneous or visceral, depends on the infective species and the immune status of the patient. Antimonial drugs are the mainstay treatment for all the clinical forms of the disease. Amphotericin B is the second-choice drug. Methods We report two clinical cases of cutaneous leishmaniasis treated with itraconazole. One case was a relapsing form unresponsive to conventional therapy. Results, Both patients achieved fast resolution of their lesions with no secondary effects. Conclusions, Itraconazole may be a valid option for the treatment of cutaneous leishmaniasis, mainly in those cases unresponsive to conventional drugs. [source] Robust control of multi-axis magnetic bearing systemsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 14 2001T.-J. Yeh Abstract This paper proposes robust control schemes for multi-axis magnetic bearing systems under current control and voltage control. The control schemes are based on a model which characterizes not only the electromagnetic interaction but also secondary effects such as flux leakage, fringing fluxes, and finite core permeance in the magnetic bearing. In the current control case, a sliding-mode-based robust controller, whose control parameters have to be deliberately chosen to account for the uni-directionality of magnetic forces, is proposed to provide robust performance against uncertain dynamics. In the voltage control case, a control scheme that combines the sliding methodology and the backstepping technique is used to provide robust performance under the influence of the electrical dynamics. It is demonstrated through simulations and experiments that, because the nonlinearity and the uncertainty inherently residing in the system behaviour are directly tackled, the proposed controllers achieve superior tracking performances compared to control lers based on linearization. Copyright © 2001 John Wiley & Sons, Ltd. [source] Relevance of the developmental toxicity of ethanol in the occupational setting: a review,JOURNAL OF APPLIED TOXICOLOGY, Issue 5 2003Lorraine F. H. Irvine Abstract Numerous studies have been conducted investigating the reproductive toxicology of ethanol, the overwhelming majority concerning the adverse effects of consuming alcohol in beverages during pregnancy. Because many of the in vivo studies were designed to model alcoholism, they used comparatively high doses and assessed relatively few endpoints. Outcomes may have been affected by disturbances of metabolism at such high exposures, giving rise to secondary effects on development. The available data on ethanol from ,conventional' developmental toxicity study test methods of the type used for regulatory hazard assessment of chemicals are limited. It is in this context, however, i.e. the use of ethanol as an industrial chemical rather than as a component of beverages, that this review is based. Using the usual criteria applied for the purpose of hazard assessment of industrial chemicals, it is concluded that there is no evidence that industrial exposure to ethanol is a developmental toxicity hazard. Developmental toxicity may result from drinking alcoholic beverages, the threshold level for all aspects of which has yet to be de,ned. This is not, however, considered relevant to the low blood alcohol concentrations resulting from any conceivable inhalation or dermal exposure in the workplace or through the directed use of any consumer product containing ethanol. Copyright © 2003 John Wiley & Sons, Ltd. [source] Modified method for external attachment of transmitters to birds using two subcutaneous anchorsJOURNAL OF FIELD ORNITHOLOGY, Issue 3 2008Tyler L. Lewis ABSTRACT Of the transmitter attachment techniques for birds, the subcutaneous anchor provides a secure attachment that yields relatively few secondary effects. However, the use of subcutaneous anchors has been limited by transmitter size and retention time. Using a modified method of attachment that utilized two subcutaneous anchors, we deployed 69 GPS transmitters, plus 13 VHF transmitters that were similar in size and weight to GPS models, on Pacific Black Brant (Branta bernicla nigricans). Prior to our study, only harnesses were used for attaching GPS transmitters on birds, mainly because GPS transmitters are too large for other external attachment techniques and implantation in the body cavity attenuates the GPS signal. Thus, to increase the size capacity of anchor attachment and to avoid the well-documented negative effects of harnesses on behavior and survival, we added a second anchor at the transmitter's posterior end. The double-anchor attachment technique was quickly and easily accomplished in the field, requiring bird handling times of <10 min. Incidental recoveries of tagged Brant indicate a high degree of transmitter retention. Five recaptured birds (4,6 weeks after deployment) and eight killed by hunters (3,6 mo after deployment) retained their GPS transmitters. For studies involving the use of relatively large transmitters, the double-anchor method appears to provide a viable alternative for external attachment. SINOPSIS Entre las técnicas para montar radiotransmisores a aves, el anclaje subcutáneo provee una forma segura de montaje que presenta muy pocos efectos secundarios. Sin embargo, la utilidad del anclaje subcutáneo ha sido limitada por el tamaño del transmisor y el tiempo de retención en el ave. Utilizando un método modificado que utiliza dos puntos subcutáneos de anclaje, desarrollamos 69 transmisores GPS y 13 transmisores VHF que replicaban el tamaño y peso de modelos GPS, y que fueron montados en individuos del ganso, Branta bernicla nigricans. Previo a este estudio, solo se habían utilizado arneses para colocar radiotransmisores en los gansos. Esto fue así porque los tipo GPS son demasiado grandes para ser colocados de otra manera y cuando se implantan en la cavidad celómica, queda atenuada la señal del transmisor. Por tal razon, y para incrementar la capacidad de anclaje del transmisor y evitar el impacto negativo documentado en los arneses (en conducta y sobrevivencia), añadimos un segundo punto de anclaje en la parte posterior del transmisor. La técnica desarrollada fue fácil de aplicar en el campo y se hizo de forma rápida (<10 minutos). Recobros incidentales de gansos (4 recapturas, 4,6 semanas después) y ocho individuos cazados (3,6 meses después) indicaron un 100% de retención de los transmisores. Para estudios que conlleven transmisores de gran tamaño, el método de doble anclaje parece proveer una alternativa adecuada. [source] Cold subduction and the formation of lawsonite eclogite , constraints from prograde evolution of eclogitized pillow lava from CorsicaJOURNAL OF METAMORPHIC GEOLOGY, Issue 4 2010E. J. K. RAVNA Abstract A new discovery of lawsonite eclogite is presented from the Lancône glaucophanites within the Schistes Lustrés nappe at Défilé du Lancône in Alpine Corsica. The fine-grained eclogitized pillow lava and inter-pillow matrix are extremely fresh, showing very little evidence of retrograde alteration. Peak assemblages in both the massive pillows and weakly foliated inter-pillow matrix consist of zoned idiomorphic Mg-poor (<0.8 wt% MgO) garnet + omphacite + lawsonite + chlorite + titanite. A local overprint by the lower grade assemblage glaucophane + albite with partial resorption of omphacite and garnet is locally observed. Garnet porphyroblasts in the massive pillows are Mn rich, and show a regular prograde growth-type zoning with a Mn-rich core. In the inter-pillow matrix garnet is less manganiferous, and shows a mutual variation in Ca and Fe with Fe enrichment toward the rim. Some garnet from this rock type shows complex zoning patterns indicating a coalescence of several smaller crystallites. Matrix omphacite in both rock types is zoned with a rimward increase in XJd, locally with cores of relict augite. Numerous inclusions of clinopyroxene, lawsonite, chlorite and titanite are encapsulated within garnet in both rock types, and albite, quartz and hornblende are also found included in garnet from the inter-pillow matrix. Inclusions of clinopyroxene commonly have augitic cores and omphacitic rims. The inter-pillow matrix contains cross-cutting omphacite-rich veinlets with zoned omphacite, Si-rich phengite (Si = 3.54 apfu), ferroglaucophane, actinolite and hematite. These veinlets are seen fracturing idiomorphic garnet, apparently without any secondary effects. Pseudosections of matrix compositions for the massive pillows, the inter-pillow matrix and the cross-cutting veinlets indicate similar P,T conditions with maximum pressures of 1.9,2.6 GPa at temperatures of 335,420 °C. The inclusion suite found in garnet from the inter-pillow matrix apparently formed at pressures below 0.6,0.7 GPa. Retrogression during initial decompression of the studied rocks is only very local. Late veinlets of albite + glaucophane, without breakdown of lawsonite, indicate that the rocks remained in a cold environment during exhumation, resulting in a hairpin-shaped P,T path. [source] The history of sweet taste: not exactly a piece of cakeJOURNAL OF MOLECULAR RECOGNITION, Issue 3 2006Pierandrea Temussi Abstract Understanding the molecular bases of sweet taste is of crucial importance not only in biotechnology but also for its medical implications, since an increasing number of people is affected by food-related diseases like, diabetes, hyperlipemia, caries, that are more or less directly linked to the secondary effects of sugar intake. Despite the interest paid to the field, it is only through the recent identification and functional expression of the receptor for sweet taste that new perspectives have been opened, drastically changing our approach to the development of new sweeteners. We shall give an overview of the field starting from the early days up to discussing the newest developments. After a review of early models of the active site, the mechanisms of interaction of small and macromolecular sweet molecules will be examined in the light of accurate modeling of the sweet taste receptor. The analysis of the homology models of all possible dimers allowed by combinations of the human T1R2 and T1R3 sequences of the sweet receptor and the closed (A) and open (B) conformations of the mGluR1 glutamate receptor shows that only ,type B' sites, either T1R2(B) and T1R3(B), can host the majority of small molecular weight sweeteners. Simultaneous binding to the A and B sites is not possible with two large sweeteners but is possible with a small molecule in site A and a large one in site B. This observation accounted for the first time for the peculiar phenomenon of synergy between some sweeteners. In addition to these two sites, the models showed an external binding site that can host sweet proteins. Copyright © 2006 John Wiley & Sons, Ltd. [source] Do "Off-Site" Adult Businesses Have Secondary Effects?LAW & POLICY, Issue 2 2009Empirical Evidence, Legal Doctrine, Social Theory Recent federal court decisions appear to limit the ability of cities to mitigate the ambient crime risks associated with adult entertainment businesses. In one instance, a court has assumed that criminological theories do not apply to "off-site" adult businesses. After developing the legal doctrine of secondary effects, we demonstrate that the prevailing criminological theory applies to all adult business models. To corroborate the theory, we report the results of a before/after quasi-experiment for an off-site adult business. When an off-site adult business opens, ambient crime risk doubles compared to a control area. As theory predicts, moreover, ambient victimization risk is most acute in night-time hours. The theoretical development and empirical results have obvious implications for the evolving legal doctrine of secondary effects. [source] Mycophenolate mofetil in combination with reduction of calcineurin inhibitors for chronic renal dysfunction after liver transplantation,LIVER TRANSPLANTATION, Issue 12 2006Georges-Philippe Pageaux The purpose of the study was to introduce mycophenolate mofetil (MMF) in liver transplant recipients with renal dysfunction to decrease calcineurin inhibitor (CNI) dosages without increasing rejection risk. In this prospective, multicenter, randomized study, chronic CNI-related renal dysfunction was defined by an increase in serum creatinine with values >140 ,mol/L and <300 ,mol/L. Patients were randomized in 2 groups. Study group: combination of MMF (2 to 3 g/day) and reduced dose of CNI ,50% of initial dose; control group: no MMF, but with the ability to reduce CNI doses, but not below 75% of initial dose. Fifty-six patients were included, 27 in the study group and 29 in the control group. In the study group, there was a significant decrease in serum creatinine values, from 171.7 ± 24.2 ,mol/L at day 0 to 143.4 ± 19 ,mol/L at month 12 and a significant increase in creatinine clearance, from 42.6 ± 10.9 mL/min to 51.7 ± 13.8 mL/min. No rejection episode was observed in the study group. In the control group, there was no improvement of renal function, assessed by the changes in serum creatinine values, from 175.4 ± 23.4 ,mol/L at day 0 to 181.6 ± 63 ,mol/L at month 12, and in creatinine clearance, from 42.8 ± 12.8 mL/min to 44.8 ± 19.7 mL/min. The differences between the 2 groups were significant: P = 0.001 for serum creatinine, and P = 0.04 for creatinine clearance. In conclusion, the introduction of MMF combined with the reduction of at least 50% of CNI dose allowed the renal function of liver transplant recipients to significantly improve at 1 year, without any rejection episode and without significant secondary effects. Liver Transpl 12:1755,1760, 2006. © 2006 AASLD. [source] Methods in Nutrition Science: Cre/loxP System for Generating Tissue-specific Knockout Mouse ModelsNUTRITION REVIEWS, Issue 6 2004Claudine H. Kos Ph.D. Editor's note: From time to time, we take the opportunity in Nutrition Reviews to highlight a particularly exciting application of sophisticated methodological advances that are relevant to the nutrition research community. In the current issue of Nutrition Reviews, Dr. Claudine Kos has provide a brief review of some of the salient features of the Cre/loxP system for generating tissue-specific knockout mouse models. Hopefully, this review will provide additional background to Dr. George Wolf's Brief Critical Review (page 253) of the use of the Cre/loxP technique by investigators to gain further insight into the function of the peroxysome proliferators-activated receptor-gamma (PPAR-,), as well as promote its further use within experimental nutrition. Alteration of the mouse genome by conventional transgenic and gene-targeted approaches has greatly facilitated studies of gene function. However, a gene alteration expressed in the germ line may cause an embryonic lethal phenotype resulting in no viable mouse to study gene function. Similarly, a gene alteration may exert its effect in multiple different cell and tissue types, creating a complex phenotype in which it is difficult to distinguish direct function in a particular tissue from secondary effects resulting from altered gene function in other tissues. Therefore, methods have been developed to control conditions such as the timing, cell-type, and tissue specificity of gene activation or repression. This brief review provides an overview of the Cre/LoxP system for generating tissue-specific knockout mouse models. [source] Interactions of Valeriana officinalis L. and Passiflora incarnata L. in a patient treated with lorazepamPHYTOTHERAPY RESEARCH, Issue 12 2009María Consuelo Carrasco Abstract There is an increasing interest in the health risks related to the use of herbal remedies. Although most consumers think that phytomedicines are safe and without side effects, interactions between complementary alternative and conventional medicines are being described. The aim of this clinical case report is to highlight the importance of the safe use of herbal remedies by providing a clinical interaction study between pharmaceutical medicines and herbal medicinal products. The case of a patient self-medicated with Valeriana officinalis L. and Passiflora incarnata L. while he was on lorazepam treatment is described. Handshaking, dizziness, throbbing and muscular fatigue were reported within the 32 h before clinical diagnosis. The analysis of family medical history ruled out essential tremor, Parkinson's disease, Wilson's disease and other symptom-related pathologies. His medical history revealed a generalized anxiety disorder and medicinal plant consumption but no neurological disorder. Appropriate physical examination was carried out. An additive or synergistic effect is suspected to have produced these symptoms. The active principles of Valerian and passionflower might increase the inhibitory activity of benzodiazepines binding to the GABA receptors, causing severe secondary effects. Due to the increase in herbal product self-medication, the use of herbal remedies should be registered while taking the personal clinical history. Multidisciplinary teams should be created to raise studies on medicinal plants with impact on medical praxis. Copyright © 2009 John Wiley & Sons, Ltd. [source] Secondary effects induced by the colon carcinogen azoxymethane in BDIX rats,APMIS, Issue 6 2004MORTEN KOBÆK-LARSEN Azoxymethane (AOM) is claimed to be a colon-specific carcinogen. In our studies, AOM was administered to adult BDIX/OrlIco rats by four weekly subcutaneous injections of 15 mg/kg body weight each , two periods of 2 weeks of AOM treatment separated by a one-week break. This treatment schedule resulted in colon carcinomas with a high frequency (75,100%) and with a high reproducibility. However, some serious side effects are associated with this carcinogen treatment. In addition to the colorectal tumours, we found small intestinal tumours, hepatic lesions and a high frequency of mesenchymal renal tumours which increased with longer latency periods. The renal tumours were only found in female rats, and this indicates a possible relation to sex hormones. We therefore analyzed both male and female kidneys for the expression of estrogen and progesterone receptors by immunohistochemical methods. A positive nuclear reaction for estrogen receptor was present in most tumour cells in all tumours and occasionally in nuclei of entrapped tubular cells, but never in glomeruli. Normal appearing renal tissue from female rats showed no positive reaction, but in male rats a slight nuclear reaction was seen in tubuli in the peripheral part of the medulla. A similar pattern was seen for progesterone receptors, but less pronounced. No rats developed tumours in the external ear canal, which is in contrast to studies performed in other rat strains. This may therefore be strain related. In order to reduce the secondary effects of the induction of colon cancer by AOM, it is advisable to use male rats only and a maximum latency period of 32 weeks. [source] Perfluorocarbon-Based Oxygen Carriers: Review of Products and TrialsARTIFICIAL ORGANS, Issue 8 2010Camila Irene Castro Abstract A viable blood substitute is still of great necessity throughout the world. Perfluorocarbon-based oxygen carriers (PFCOCs) are emulsions that take advantage of the high solubility of respiratory gases in perfluorocarbons (PFCs). Despite attractive characteristics, no PFCOC is currently approved for clinical uses. Some PFCOCs have failed due to secondary effects of the surfactants employed, like Fluosol DA, whereas others to adverse cerebrovascular effects on cardiopulmonary bypass, such as Oxygent. Further in-depth, rigorous work is needed to overcome the annotated failures and to obtain a safe PFCOC approved for human use. The aim of this study is to review in detail the most-used PFCOCs, their formulation, and preclinical and clinical trials, and to reflect upon causes of failure and strategies to overcome such failures. [source] Unverzichtbar gegen Bakterien: Antibiotika.CHEMIE IN UNSERER ZEIT (CHIUZ), Issue 5 200980 Jahre Verwendung von Antibiotika in der Medizin Abstract Auch 80 Jahre nach der Entdeckung von Penicillin ist die Forschung nach neuen Antibiotika noch nicht abgeschlossen. Zunehmendes Auftreten von Resistenzen gegenüber den verwendeten Antibiotika erfordern einen verantwortungsvollen Einsatz bekannter Anibiotika und die Entwicklung verbesserter Medikamente. Mittlerweile existieren 8000 antibiotisch wirksame Substanzen, von denen ca. 100 in der Medizin angewandt werden. Trotzdem gibt es zahlreiche Infektionen, die nicht ausreichend behandelt werden können. Antibiotika werden in der Human- und Veterinärmedizin eingesetzt. Der bedenkliche Einsatz als Ergotropika, um die Infektionsraten von Masttieren zu vermindern und die Futterverwertung der Tiere zu steigern, konnte in den letzten Jahren zurückgedrängt werden. Die teils unsachgemäße Anwendung erzeugt einen selektiven Druck, der Resistenzen bei den Erregern hervorruft. Ihr bedrohlicher Einfluss auf die Therapie vor allem gramnegativer Bakterien könnten manche Teile der Welt in eine präantibiotische Ära zurückversetzen, da sich adäquate Therapiemöglichkeiten zunehmend verringern. Dies unterstreicht wiederum die Wichtigkeit neue Antibiotika bzw. neue Therapieansätze zu entwickeln. Ideen dazu gibt es genug. Eighty years after the recovery of Penicillin the search for new antibiotics is still ongoing. By now there exist 8000 effective antibiotics, from which 100 have medical applications. Nevertheless there exist a lot of infections, which cannot be sufficiently treated. New antibiotics should have a specific mode of function that differs from known antibiotics. Additionally they should avoid secondary effects on humans, have a good resorption and act at the right place in the body, without being immediately released. [source] | ||||||||||||||||