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1.
Lasers Surg Med ; 41(2): 96-103, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19226578

RESUMEN

BACKGROUND: The occurrence of non-melanoma skin cancer (NMSC), including actinic keratosis (AK) is increasing all over the world. The detection and diagnosis of NMSC is not optimal in clinical practice. Complementary methods for detection and accurate demarcation of NMSC at an early stage are needed in order to limit the damage caused by tumours. OBJECTIVE: The purpose of the present study was to use a large area skin fluorescence detection system to detect early NMSCs (clinical visible as well as non-visible lesions) in the face, neck, chest, back and hands of patients treated with UV and outdoor workers. METHODS: Fluorescence detection with a purpose-made digital camera and software (Dyaderm combined with 5-aminolevulinic acid (5-ALA) encapsulated in liposomes. RESULTS: In 93 consecutively referred patients positive skin fluorescence was detected in 61 patients. After histological examination the positive fluorescence appeared to be correlated to benign lesions in 28 patients (sebaceous gland hyperplasia in 22 patients) and to (pre-) malignant lesions in 33 patients (actinic keratosis in 29, BCC in 3 and SCC in 1 patient). False negative fluorescence was found in only one lesion. In five patients the FD technique used in this study appeared to be more sensitive for the identification of (pre-) malignant lesions than the clinical examination. This is in contrast with FD techniques used in previous studies. CONCLUSION: Diagnostic skin fluorescence using liposomal encapsulated 5-ALA and a specialised computerised detection and visualisation system offers the possibility for detection of NMSC at an early, pre-clinical stage. The technique is well suited to examine large areas of skin. It also identifies areas of most interest for performing confirmatory skin biopsies, as well as pre-operative assessment of boundaries of skin malignancies, and finally, the technique is applicable in the control and follow-up of skin cancer treatment.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias Cutáneas/diagnóstico , Ácido Aminolevulínico , Femenino , Fluorescencia , Humanos , Liposomas , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Fármacos Fotosensibilizantes
2.
Int Immunopharmacol ; 8(2): 188-96, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18182225

RESUMEN

Kinin B1 and B2 receptor (R) gene expression (mRNA) is increased in the sensory system after peripheral nerve injury. This study measured the densities of B1R and B2R binding sites in the spinal cord and dorsal root ganglia (DRG) by quantitative autoradiography, and evaluated the effects of two selective non-peptide antagonists at B1R (LF22-0542) and B2R (LF16-0687) on pain behavior after partial ligation of the left sciatic nerve. Increases of B1R binding sites were seen in superficial laminae of the ipsi- and contralateral spinal cord at 2 and 14 days while B2R binding sites were increased on the ipsilateral side at 2 days and on both sides at 14 days. In DRG, B1R and B2R binding sites were significantly increased at 2 days (ipsilateral) and 14 days on both sides. Whereas tactile allodynia started to develop progressively from 2 to 25 days post-ligation, the occurrence of cold allodynia and thermal hyperalgesia became significant from day 8 and day 14 post-ligation, respectively. At day 21 after sciatic nerve ligation, thermal hyperalgesia was blocked by LF22-0542 (10 mg/kg, s.c.) and LF16-0687 (3 mg/kg, s.c.), yet both antagonists had no effect on tactile and cold allodynia. Data highlight the implication of both kinin receptors in thermal hyperalgesia but not in tactile and cold allodynia associated with peripheral nerve injury. Hence LF22-0542 and LF16-0687 present therapeutic potential for the treatment of some aspects of neuropathic pain.


Asunto(s)
Hiperalgesia/etiología , Receptor de Bradiquinina B1/fisiología , Receptor de Bradiquinina B2/fisiología , Acrilamidas/farmacología , Animales , Sitios de Unión , Modelos Animales de Enfermedad , Fumaratos/farmacología , Masculino , Quinolinas/farmacología , Ratas , Ratas Sprague-Dawley
3.
Br J Pharmacol ; 172(10): 2573-87, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25598508

RESUMEN

BACKGROUND AND PURPOSE: Phosphorylation of δ opioid receptors (DOP receptors) by cyclin-dependent kinase 5 (CDK5) was shown to regulate the trafficking of this receptor. Therefore, we aimed to determine the role of CDK5 in regulating DOP receptors in rats treated with morphine or with complete Freund's adjuvant (CFA). As µ (MOP) and DOP receptors are known to be co-regulated, we also sought to determine if CDK5-mediated regulation of DOP receptors also affects MOP receptor functions. EXPERIMENTAL APPROACH: The role of CDK5 in regulating opioid receptors in CFA- and morphine-treated rats was studied using roscovitine as a CDK inhibitor and a cell-penetrant peptide mimicking the second intracellular loop of DOP receptors (C11-DOPri2). Opioid receptor functions were assessed in vivo in a series of behavioural experiments and correlated by measuring ERK1/2 activity in dorsal root ganglia homogenates. KEY RESULTS: Chronic roscovitine treatment reduced the antinociceptive and antihyperalgesic effects of deltorphin II (Dlt II) in morphine- and CFA-treated rats respectively. Repeated administrations of C11-DOPri2 also robustly decreased Dlt II-induced analgesia. Interestingly, DAMGO-induced analgesia was significantly increased by roscovitine and C11-DOPri2. Concomitantly, in roscovitine-treated rats the Dlt II-induced ERK1/2 activation was decreased, whereas the DAMGO-induced ERK1/2 activation was increased. An acute roscovitine treatment had no effect on Dlt II- or DAMGO-induced analgesia. CONCLUSIONS AND IMPLICATIONS: Together, our results demonstrate that CDK5 is a key player in the regulation of DOP receptors in morphine- and CFA-treated rats and that the regulation of DOP receptors by CDK5 is sufficient to modulate MOP receptor functions through an indirect process.


Asunto(s)
Quinasa 5 Dependiente de la Ciclina/metabolismo , Receptores Opioides delta/metabolismo , Receptores Opioides mu/metabolismo , Analgesia , Animales , Péptidos de Penetración Celular/síntesis química , Péptidos de Penetración Celular/farmacología , Quinasa 5 Dependiente de la Ciclina/antagonistas & inhibidores , Interacciones Farmacológicas , Encefalina Ala(2)-MeFe(4)-Gli(5)/farmacología , Ganglios Espinales/metabolismo , Lipopéptidos/síntesis química , Lipopéptidos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Morfina/farmacología , Oligopéptidos/antagonistas & inhibidores , Oligopéptidos/farmacología , Dimensión del Dolor/efectos de los fármacos , Purinas/farmacología , Ratas , Roscovitina
4.
J Bone Miner Res ; 9(8): 1179-89, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7976500

RESUMEN

PTH is regarded conventionally as a catabolic hormone that stimulates osteoclastic resorption of bone. However, it has been known since 1932 that intermittent pulses of PTH stimulate bone formation in animals and humans. PTH independently activates two signal mechanisms: one that stimulates adenylyl cyclase and one that stimulates protein kinase C (PKC). The goal of this study was to use the 3- to 5-month-old ovariectomized (OVX) rat model to determine which of the two signal mechanisms is responsible for the anabolic action of PTH on bone. OVX triggered a large loss of trabecular bone without significantly affecting the normal slow growth of cortical bone in the distal halves of the femora. Daily injections of human hPTH(1-34) fragment (1 nmol/100 g body weight), which stimulated both adenylyl cyclase and membrane-associated PKC activity in osteoblast-like ROS 17/2 rat osteosarcoma cells, stimulated the growth of both cortical and trabecular bone in the OVX rats. Daily injections of the same dose of hPTH(1-31), which stimulated adenylyl cyclase but not PKC in ROS 17/2 cells, stimulated trabecular bone growth in the OVX rats less effectively than hPTH(1-34), but it stimulated cortical bone growth as rapidly and as dramatically as hPTH(1-34). Injections of equimolar amounts of desamino-hPTH(1-34) [N-propionyl(2-3)hPTH-amide], which stimulated PKC as strongly as hPTH(1-34) in ROS 17/2 cells but had a drastically reduced ability to stimulate adenylyl cyclase, or injections of recombinant hPTH(8-84) which stimulated PKC only in the ROS 17/2 cells, did not stimulate cortical or trabecular bone growth in the OVX animals. Thus, cyclic AMP and cyclic AMP-dependent protein kinases may be the primary mediators of the anabolic action of intermittent pulses of PTH on bone in OVX rats.


Asunto(s)
Adenilil Ciclasas/metabolismo , Desarrollo Óseo/efectos de los fármacos , Hormona Paratiroidea/farmacología , Fragmentos de Péptidos/farmacología , Adenilil Ciclasas/efectos de los fármacos , Animales , Densidad Ósea/efectos de los fármacos , Calcio/análisis , Femenino , Fémur/química , Fémur/efectos de los fármacos , Fémur/crecimiento & desarrollo , Inyecciones Subcutáneas , Masculino , Ovariectomía , Proteína Quinasa C/efectos de los fármacos , Proteína Quinasa C/metabolismo , Ratas , Ratas Sprague-Dawley
5.
J Bone Miner Res ; 9(6): 943-9, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8079668

RESUMEN

The protein kinase C (PKC) activation domain of the parathyroid hormone (PTH) was believed to be the 28-34 region of the molecule. We have now shown that PTH-(29-32) is the smallest PTH fragment that can stimulate significantly membrane-associated PKC activity in ROS 17/2 rat osteosarcoma cells. As was previously shown for full-length PTH-(1-84) and the fully bioactive PTH-(1-34) fragment, there were two peaks in the PKC response to PTH-(29-32): one peak was obtained with low picomolar concentrations and the other with much higher nanomolar concentrations of the fragment. The PKC-activating ability was unaffected by the loss of Asn33 and Phe34, but it was abolished by removing His32. Thus, the PTH-(28-31) and PTH-(29-31) fragments did not stimulate membrane-associated PKC activity. The much larger PTH-(1-31) fragment also did not stimulate membrane-associated PKC activity, although it stimulated adenylyl cyclase as strongly as PTH-(1-34). This functional sensitivity to the loss of the polar His32 was not caused by a specific need for His or another polar amino acid in this position because replacing it with the apolar Leu did not abolish adenylyl cyclase or PKC activation. It is concluded that the minimum, fully functional PKC activation domain of the PTH molecule is Gln29-Asp30-Val31-His32.


Asunto(s)
Hormona Paratiroidea/química , Proteína Quinasa C/química , Adenilil Ciclasas/metabolismo , Secuencia de Aminoácidos , Animales , Activación Enzimática , Humanos , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Osteosarcoma , Fragmentos de Péptidos/química , Proteína Quinasa C/metabolismo , Ratas , Células Tumorales Cultivadas
6.
J Bone Miner Res ; 8(4): 497-503, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8475799

RESUMEN

N-terminal fragments of PTH-related protein (PTHrP), PTHrP-(1-34), and PTHrP-(1-40) stimulated both adenylyl cyclase and a mechanism that increases membrane-associated protein kinase C (PKC) activity in ROS 17/2 rat osteosarcoma cells. There were two peaks in the PKC response to the N-terminal PTHrP fragments: one peak was obtained with picomolar and the other with nanomolar PTHrP concentrations. The PKC-stimulating picomolar concentrations of the PTHrP fragments did not detectably stimulate adenylyl cyclase, but the nanomolar concentrations did. Since a similar two-peak response of PKC activity was obtained with PTHrP-(28-34), the single, N-terminal PKC activation domain of the PTHrP is in the same 28-34 region of the molecule as that of PTH despite this region having different primary amino acid sequences in the two hormones. Unlike PTH, PTHrP has a second PKC activation domain, as indicated by the ability of picomolar concentrations of the PTHrP-(107-111) fragment to stimulate maximally membrane-associated PKC activity in the osteosarcoma cells.


Asunto(s)
Hormona Paratiroidea/fisiología , Proteína Quinasa C/metabolismo , Proteínas/fisiología , Adenilil Ciclasas/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Huesos/enzimología , Activación Enzimática/fisiología , Humanos , Datos de Secuencia Molecular , Osteosarcoma , Proteína Relacionada con la Hormona Paratiroidea , Fragmentos de Péptidos , Fosforilación , Ratas , Células Tumorales Cultivadas
7.
Endocrinology ; 130(1): 53-60, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1727720

RESUMEN

The PTH activates both adenylate cyclase and a mechanism that increases membrane-associated protein kinase-C (PKC) activity. To define the hormone's PKC activation domain we have used a panel of PTH fragments and ROS 17/2 rat osteosarcoma cells as the target cells. PTH equally and maximally increased PKC activity in ROS 17/2 cell membranes at physiological concentrations between 1-50 pM and 5-50 nM, but not at intermediate concentrations or concentrations above 50 nM. The PKC-stimulating picomolar concentrations of PTH did not stimulate adenylate cyclase in ROS 17/2 cells, while the PKC-stimulating nanomolar concentrations of the hormone did stimulate adenylate cyclase, with an EC50 of 1-2 nM. Very high concentrations of PTH, such as 100 nM, that did not increase membrane PKC activity were still able to maximally stimulate adenylate cyclase. PTH fragments lacking the N-terminal amino acids needed for adenylate cyclase activation increased membrane PKC activity, and the PKC activation domain was found to lie within the 28-34 region of the PTH molecule. This was confirmed by showing that optimally effective picomolar concentrations of the human PTH-(28-34) fragment itself were able to increase membrane-associated PKC activity to the same extent as the optimally effective picomolar concentrations of the intact PTH-(1-84) or the larger PTH-(1-34) or PTH-(3-34) fragments.


Asunto(s)
Hormona Paratiroidea/farmacología , Fragmentos de Péptidos/farmacología , Proteína Quinasa C/metabolismo , Animales , Activación Enzimática , Osteosarcoma/enzimología , Ratas , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas , Fosfolipasas de Tipo C/análisis
8.
Hypertension ; 33(3): 823-9, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10082494

RESUMEN

-To protect from metabolism and to improve potency of the AcLys-[D-betaNal7,Ile8]desArg9-bradykinin (BK) (R 715), we prepared and tested 3 analogues containing alpha-methyl-L-Phe ([alphaMe]Phe) in position 5: these are the AcLys-[(alphaMe)Phe5,D-betaNal7, Ile8]desArg9BK (R 892), Lys-Lys-[(alphaMe)Phe5,D-betaNal7, Ile8]desArg9BK (R 913), and AcLys-Lys-[(alphaMe)Phe5,D-betaNal7, Ile8]desArg9BK (R 914). The new compounds were tested against the contractile effect induced by desArg9BK on 2 B1 receptor bioassays, the human umbilical vein, and the rabbit aorta. Their antagonistic activities were compared with those of the early prototypes (Lys-[Leu8]desArg9BK and [Leu8]desArg9BK) and with other recently described peptide antagonists. The 3 (alphaMe)Phe analogues showed high antagonistic potencies (pA2) at both the human (8.8, 7.7, and 8. 7, respectively) and rabbit (8.6, 7.8, and 8.6, respectively) B1 receptors. No antagonistic effects (pA2<5) were observed on the B2 receptors that mediate the contractile effects of BK on the human umbilical vein, the rabbit jugular vein, and the guinea pig ileum. Moreover, these new B1 antagonists were found to be resistant to in vitro degradation by purified angiotensin-converting enzyme from rabbit lung. The Nalpha-acetylated forms, R 892 and R 914, were resistant to aminopeptidases from human plasma. In vivo antagonistic potencies (ID50) of B1 receptor antagonists were evaluated in anesthetized lipopolysaccharide-treated (for B1 receptor) and nontreated (for B2 receptor) rabbits against the hypotensive effects of exogenous desArg9BK and BK. R 892 efficiently inhibited (ID50 2.8 nmol/kg IV) hypotension induced by desArg9BK without affecting that evoked by BK (ID50 >600 nmol/kg IV). Conversely, the peptide antagonists Lys-Lys-[Hyp3,Igl5,D-Igl7,Oic8]desArg9BK (B 9858) and DArg-[Hyp3,Thi5,D-Tic7,Oic8] desArg9BK (S 0765) showed dual B1/B2 receptor antagonism in vitro and in vivo. It is concluded that R 892 and congeners provide selective, highly potent, and metabolically stable B1 kinin receptor antagonists that can be useful for the assessment of the physiological and pathological roles of kinin B1 receptors.


Asunto(s)
Bradiquinina/análogos & derivados , Péptidos/farmacología , Receptores de Neuroquinina-3/antagonistas & inhibidores , Animales , Presión Sanguínea/efectos de los fármacos , Bradiquinina/química , Bradiquinina/farmacología , Humanos , Calidina/análogos & derivados , Calidina/química , Calidina/farmacología , Péptidos/química , Peptidil-Dipeptidasa A , Fenilalanina/análogos & derivados , Fenilalanina/química , Plasma , Conejos , Factores de Tiempo
9.
Hypertension ; 28(5): 833-9, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8901831

RESUMEN

We tested several peptides related to des-Arg9-bradykinin as stimulants or inhibitors of B1 (rabbit aorta, human umbilical vein) and B2 (rabbit jugular vein, guinea pig ileum, human umbilical vein) receptors. We also incubated the compounds with purified angiotensin-converting enzyme from rabbit lung to test their resistance to degradation. We evaluated apparent affinities (in terms of the affinity constant pA2) of compounds and their potential residual agonistic activities (alpha E). Bradykinin and des-Arg9-bradykinin were used as agonists for the B2 and B1 receptors, respectively. Degradation of peptides by the angiotensin-converting enzyme was prevented in the presence of a D-residue in position 7 of des-Arg9-bradykinin. Replacement of Pro7 with D-Tic combined with Leu, Ile, Ala, or D-Tic in position 8 led to weak B1 receptor antagonists, some of which had strong residual agonistic activities on the B2 receptor preparations. The use of D-beta Nal in position 7, combined with Ile in position 8 and AcLys at the N-terminal (eg, AcLys[D-beta Nal7, Ile8]des-Arg9-bradykinin) gave the most active B1 receptor antagonist (pA2 of 8.5 on rabbit aorta and human umbilical vein), which is also partially resistant to enzymatic degradation. Extension of the N-terminal end by Sar-Tyr-epsilon Ahx (used for labeling purposes) and even cold-labeling of Tyr with iodine were compatible with high, selective, and specific antagonism of the B1 receptors. We compared some compounds with some already known B1 receptor antagonists to underline the novelty of new peptidic compounds.


Asunto(s)
Antagonistas de los Receptores de Bradiquinina , Bradiquinina/análogos & derivados , Péptidos/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Femenino , Cobayas , Humanos , Masculino , Péptidos/síntesis química , Conejos , Relación Estructura-Actividad , Venas Umbilicales/efectos de los fármacos , Venas Umbilicales/metabolismo
10.
J Med Chem ; 35(1): 151-7, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1732523

RESUMEN

Several potential photoaffinity analogues of the peptide hormone vasopressin (VP) were prepared by classical solid-phase peptide synthesis using two different pathways. Peptide sequences were built by introduction of (a) Nar-protected aminophenylalanine or (b) nitrophenylalanine in the photolabeling position. Conversion to the azido peptide was completed in pathway a after cleavage and before purification and in pathway b from small quantities of purified nitrophenylalanine-containing precursor peptides. V1 receptor binding properties were measured using membranes prepared from rat liver cells. The binding potential of agonistic VP structures was abolished by the introduction of an azido or a nitro group into the aromatic side chain at position 3. Cyclo desamino-beta,beta-dialkyl-Cys1-type VP antagonist structures were prepared with the photoactivable moiety in position 2 and an iodination residue in position 9. One particular compound, [Dmpa1, Phe(N3)2, Val4, Lys8,D-Tyr9]VP (8), containing beta,beta-dimethyl-beta-mercaptopropionic acid in position 1, had excellent binding properties, both in the radioiodinated (Kd = 4.8 +/- 1.9 x 10(-10) M) and noniodinated form (Kd = 6.4 +/- 0.98 x 10(-10) M). The analogues with long-chain beta-alkylation (diethyl and pentamethylene) and the linear antagonist photolabel showed significantly less affinity. Optimal binding properties were obtained within a very narrow range of hydrophobicity; greater or lesser hydrophobicity was correlated to less potent binding. The precursor analogues, containing nitrophenylalanine, displayed a structure-activity relationship similar to that of the azido peptides. The most potent analogues will be used for receptor labeling studies. A linear antagonist structure having a photosensitive group in position 1, has also been prepared, but this compound displayed much less affinity than the cyclic antagonists. The most potent compounds were also highly selective for the V1 receptor and did not recognize the V2 receptor from other preparations.


Asunto(s)
Marcadores de Afinidad/síntesis química , Vasopresinas/síntesis química , Marcadores de Afinidad/metabolismo , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Hígado/metabolismo , Datos de Secuencia Molecular , Ratas , Relación Estructura-Actividad , Vasopresinas/metabolismo
11.
J Med Chem ; 40(20): 3271-9, 1997 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-9379447

RESUMEN

Lipidated angiotensin II (Ang) agonists and antagonists were synthesized and evaluated for their biological activities for eventual use an antimyoproliferative agents. Solid phase peptide synthesis was used for the assembly of the peptides with the Fmoc protection scheme. N-Acetyl-Ser1 Ang was palmitoylated on the serine hydroxyl function. The nonpalmitoylated analogue retained one-third of Ang's affinity toward the AT1 receptor on bovine adrenal cortex membranes, and the palmitoylated analogue was essentially inactive. Upon enzymatic lipolysis or mild saponification of the palmitoylated peptide, biological activity was restored. An analogous compound of Ang, N-acetyl-Ser1,beta-D-naphthylalanine8 ([NAcSer1,D-Nal8]Ang), was a pure antagonist on rabbit aorta but with lower affinity. Its O-palmitoylated form was inactive as well but was easily converted to the nonlipidated active form by lipolysis or saponification. Direct palmitoylation of [sarcosine1]Ang with palmitoyl chloride was obtained on the free phenolic hydroxyl of Tyr4 on solid phase on an otherwise fully protected peptide. This lipopeptide was fully active, was comparable to [Sar1]Ang, and exhibited strongly prolonged activity. Lipolysis and saponification under mild conditions yielded standard [Sar1]Ang. The corresponding [Sar1,D-Nal8]Ang was a potent and very long-lasting antagonist (pA2 = 8.1), and its analogous palmitoyl phenyl ester in position 4 was active in its palmitoylated form (antagonist) and, again, returned to the nonlipidated form upon saponification or lipolysis. [Sar1,Tyr4(O-octadecyl)]Ang, an analogue to Tyr-palmitoylated [Sar1]Ang with an octadecyl phenyl ether in position 4, was also prepared. Surprisingly, the ether compound was inactive. Premature hydrolysis of the palmitoyl phenyl ester peptide was excluded by HPLC analysis, and the activity of the ester peptide is attributed to a putative hydrogen bond that may be critical for biological activity. The discovery of potent biologically active lipidated antagonists of Ang gives access to potential antimyoproliferative agents with numerous application possibilities.


Asunto(s)
Angiotensina II/análogos & derivados , Ácido Palmítico/metabolismo , Corteza Suprarrenal/efectos de los fármacos , Corteza Suprarrenal/metabolismo , Angiotensina II/agonistas , Angiotensina II/antagonistas & inhibidores , Angiotensina II/metabolismo , Animales , Aorta/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Bovinos , Cromatografía Líquida de Alta Presión , Lipólisis , Modelos Químicos , Conejos , Relación Estructura-Actividad
12.
J Med Chem ; 31(10): 1907-10, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2459385

RESUMEN

The N-terminal hexa- or pentapeptide sequences of the three mammalian tachykinins substance P, neurokinin A, and neurokinin B have been synthesized by the conventional solid-phase procedure with 6-aminocaproyl-S-(acetamidomethyl)cysteine as a C-terminal spacer and attachment function. A fourth sequence, with an additional N-terminal 6-aminocaproyl residue on the substance P-hapten sequence, was cyclized N- to C-terminally. For this purpose, a four-level protection scheme has been applied: BOC-TFA for N-terminal protection and cleavage; TFA-stable but HF-labile anchoring function and side-chain protection; S-acetamidomethyl for semipermanent thiol protection. The side chain amino function of Lys was protected with NO2Z, stable against HF but readily cleaved with hydrogenation. The hapten sequences were coupled to maleimidated BSA, after the Acm group was removed by mercury/hydrogen sulfide treatment. Mice immunized with the three linear hapten sequences produced sera that were specific in enzyme-linked immunosorbant assay for the presented hapten and the respective tachykinin but displayed no crossreactivity at all toward the other haptens nor to one of the other tachykinins. It is concluded that this approach produced antisera, specific and selective for its respective mammalian tachykinins.


Asunto(s)
Taquicininas/inmunología , Animales , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática , Femenino , Ratones , Ratones Endogámicos BALB C , Neuroquinina A/inmunología , Neuroquinina B/inmunología , Sustancia P/inmunología , Taquicininas/síntesis química
13.
J Med Chem ; 40(9): 1373-80, 1997 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-9135034

RESUMEN

In a search for analogues of human parathyroid hormone (hPTH) with improved activities and bioavailabilities, we have prepared the following three lactam analogues of hPTH-(1-31)-NH2 (1) or [Leu27]hPTH-(1-31)-NH2 (2): [Leu27]cyclo(Glu22-Lys26)-hPTH-(1-31)-NH2 (3), [Leu27]cyclo(Lys26-Asp30)-hPTH-(1-31)-NH2 (4), and cyclo(Lys27-Asp30)-hPTH-(1-31)-NH2 (5). Analogues 1, 2, and 5 had seven or eight residues of alpha-helix, as estimated from their circular dichroism (CD) spectra, in contrast to 12 residues in cyclic analogues 3 and 4. Thus, lactams 3 and 4 stabilized a helix previously shown to exist within residues 17-29. The adenylyl cyclase activity (EC50), measured in rat osteosarcoma 17/2 cells, of 5 (40.3 +/- 2.3 nM) was half that of its linear form 1 (19.9 +/- 3.9 nM). The linear Leu27 mutant 2 was twice as active (11.5 +/- 5.2) as analogue 1, and lactam analogue 3 was 6-fold more active (3.3 +/- 0.3 nM). Lactam analogue 4 had less activity (16.9 +/- 3.3 nM) than 2, its linear form. Peptides hPTH-(1-30)-NH2 (6), [Leu27]hPTH-(1-30)-NH2 (7), and [Leu27]cyclo(Glu22-Lys26)-hPTH-(1-30)-NH2 (8) all had AC-stimulating activities similar to that of 1. When injected intravenously, with a dose of 0.8 nmol/100 g of analogue in acid saline, hypotensive effects paralleled their adenylyl cyclase activities. They behaved quite differently when applied subcutaneously. Analogues 1, 5, and 6, the weakest, showed about half the drop in blood pressure observed with 3 and 4, the most active. In contrast, the time required to reach a maximum drop in blood pressure of 4-8, after subcutaneous administration, was 2-4 times that of the other analogues. Thus, the bioavailabilities of the lactam analogues, unlike their adenylyl cyclase-stimulating activities, were highly dependent on the presence or conformation of Val31.


Asunto(s)
Adenilil Ciclasas/metabolismo , Antihipertensivos/química , Lactamas/química , Hormona Paratiroidea/química , Receptores de Hormona Paratiroidea/metabolismo , Secuencia de Aminoácidos , Aminoácidos/análisis , Animales , Antihipertensivos/síntesis química , Antihipertensivos/metabolismo , Antihipertensivos/farmacología , Presión Sanguínea/efectos de los fármacos , Dicroismo Circular , Activación Enzimática , Humanos , Lactamas/síntesis química , Lactamas/metabolismo , Lactamas/farmacología , Modelos Moleculares , Datos de Secuencia Molecular , Osteoblastos/enzimología , Hormona Paratiroidea/metabolismo , Hormona Paratiroidea/farmacología , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/farmacología , Conformación Proteica , Estructura Secundaria de Proteína , Ratas , Células Tumorales Cultivadas
14.
Antiviral Res ; 40(1-2): 45-51, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9864045

RESUMEN

Adenoviruses encode a cysteine protease (AVP) which carries out highly specific cleavages on at least seven viral proteins and two cellular proteins. Virus infectivity is dependent on this function. The three-dimensional positions of the amino acids involved in catalysis display a striking similarity to those of papain, suggesting a similar catalytic mechanism. This similarity has prompted us to compare the effect of papain inhibitors on the two enzymes. AVP and papain activity was tested on a fluorescent peptide substrate as well as on metabolically labeled adenovirus (Ad2) precursor proteins. Hep2 cells infected with Ad2 were exposed to inhibitors and assayed for, (a) infectious virus, (b) in situ Ad2 protease activity, (c) physical particle production and their polypeptide composition. We found that in both substrate systems AVP was sensitive to the papain inhibitors benzamidoacetonitrile, acetamidoacetonitrile and N-methoxyphenylalanine glycylnitrile, and that the degree of sensitivity was influenced by the substrate. Unlike papain, AVP was relatively insensitive to E64. In ex vivo tests, Hep2 cells infected with Ad2 were exposed to inhibitors and assayed for, (a) infectious virus, (b) in situ Ad2 protease activity, (c) physical particle production and their polypeptide composition. A 4-fold reduction in virus titer was obtained when the inhibitors were added between 17 and 25 h after infection. Processing of precursor proteins was also inhibited yet the production of physical particles was only reduced 2-fold. These experiments show that papain inhibitors are also capable of inhibiting the adenovirus protease both in vitro and ex vivo, thus forging a possible link between structural similarity and functionality.


Asunto(s)
Acetonitrilos/farmacología , Adenovirus Humanos/efectos de los fármacos , Antivirales/farmacología , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/farmacología , Inhibidores Enzimáticos/farmacología , Nitrilos/farmacología , Papaína/antagonistas & inhibidores , Catálisis , Humanos , Células Tumorales Cultivadas
15.
Peptides ; 13(1): 7-11, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1535709

RESUMEN

Highly potent and specific peptide hormone analogues with fluorescent reporter groups are current research goals. Until now, however, only moderately potent analogues have been described. We report here several types of vasopressin (VP) analogues with different fluorophores attached to the peptide. In a first series, fluorophores were attached to the free epsilon amino function of [des-amino1-lysine8]VP (dLVP), producing agonistic analogues. In a second series, reporter groups were added to the N-terminal of open-chain antagonist structures. The biological activities of these analogues were assessed by two different sets of experiments: 1) The measurement of their binding affinities towards the V1a-vasopressin receptor subtype from WRK1 cells or rat liver membrane preparations; 2) Their ability to stimulate the phospholipase C activity in WRK1 cells. As expected, a simple acylation of fluorophores to dLVP resulted in a considerable loss of affinity. If however, the Lys8 side chain was extended through double Schiff-base formation with glutaraldehyde-ethylenediamine followed by reduction to an aminoalkyl aminoalkylamine, single fluorophores could be added without loss of affinity compared to VP. The open-chain analogues, on the other hand, while displaying weak affinity, nevertheless exhibited pure antagonistic behavior.


Asunto(s)
Antagonistas de Receptores de Angiotensina , Desamino Arginina Vasopresina/análogos & derivados , Colorantes Fluorescentes/química , Vasopresinas/antagonistas & inhibidores , Secuencia de Aminoácidos , Animales , Células Cultivadas , Desamino Arginina Vasopresina/química , Desamino Arginina Vasopresina/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática , Colorantes Fluorescentes/metabolismo , Hígado/metabolismo , Membranas/metabolismo , Datos de Secuencia Molecular , Ratas , Receptores de Vasopresinas , Transducción de Señal/efectos de los fármacos , Fosfolipasas de Tipo C/efectos de los fármacos
16.
Rofo ; 132(3): 309-15, 1980 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-6448788

RESUMEN

Injuries to the epiphysel plates without involvement of the epiphyses or metaphyses, such as crush fractures or pure epiphysiolysis may be difficult to diagnose radiologically. Thirteen bone scans after damage to the growth plate have been performed on eight children. These indicate that these scans are able to diagnose lesions of the epiphyseal plates at an early stage and with certainty. The scintigrams also provide information concerning the healing process of the plate; they indicate when healing has been completed and when the extremity can be used for weight-bearing again. Radiation exposure of the children during scintigraphy with 99mTc-polyphosphate is within acceptable limits.


Asunto(s)
Epífisis/lesiones , Fracturas Óseas/diagnóstico por imagen , Tecnecio , Adolescente , Niño , Epífisis/diagnóstico por imagen , Epífisis Desprendida/diagnóstico por imagen , Femenino , Peroné/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Masculino , Polifosfatos , Radiografía , Cintigrafía , Radioisótopos de Estroncio , Tibia/diagnóstico por imagen
17.
Int J Occup Environ Health ; 4(2): 79-84, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10026468

RESUMEN

In a case-control study performed in an area of former coal, iron, and steel industries, the professional and lifestyle histories of 412 male urothelial bladder cancer inpatients (cases) and 414 inpatients with benign prostatic hyperplasia (controls) were investigated. Smoking habits were identified as the main confounder for occupational bladder cancer risk. Two hundred and forty (58.3%) of the bladder cancer inpatients and 146 (35.3%) of the inpatients with benign prostatic hyperplasia were smokers. The percentage of ex-smokers in the bladder cancer cases was 10.2%; the percentage of ex-smokers in the controls was 9.7%. Smoking-adjusted Mantel-Haenszel estimates of the odds ratios (OR&infMH;) for bladder cancer were elevated in underground hard-coal miners (OR&infMH; =2. 54, 95% CI =[1.64; 3.93]), chemical workers (OR&infMH; =2.16, 95% CI =[0.87; 5.38]), painters/varnishers (OR&infMH; = 2.42, 95% CI =[1. 05; 5.57]), technicians (OR&infMH; = 1.99, 95% CI =[0.95; 4.16]), and foundry workers (OR&infMH; = 2.22, 95% CI = [0.53; 9.08]). Administrative officers had significantly lower smoking-adjusted odds ratios (OR&infMH; = 0.61, 95% CI = [0.42; 0.88]). Although statistically not significant, the results of the Breslow-Day test of homogeneity of the odds ratios over the strata are compatible with interactions between tobacco smoking and the occupations of underground hard-coal miners (chi(2)&infBD; = 4.91, p=0.07) and chemical workers (chi(2)&infBR; = 3.32, p=0.06).


Asunto(s)
Minas de Carbón , Metalurgia , Enfermedades Profesionales/etiología , Neoplasias de la Vejiga Urinaria/etiología , Adulto , Estudios de Casos y Controles , Factores de Confusión Epidemiológicos , Alemania , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Hiperplasia Prostática/etiología , Factores de Riesgo , Fumar/efectos adversos , Encuestas y Cuestionarios , Urotelio
18.
Chirurg ; 50(10): 643-6, 1979 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-92395

RESUMEN

A transhepatic drainage tube was used in 27 patients suffering from echinococcus alveolaris of the liver of malignant process of the portal fissure from 1967 to 1978. If an hepatocholangioenterostomy is not possible, another surgical palliative procedure is necessary for drainage of the bile. The transhepatic drainage tube is a simple palliative method. The technique of this procedure, the indications, the possible complications, and the advantages are reported.


Asunto(s)
Neoplasias de los Conductos Biliares/cirugía , Drenaje/métodos , Hígado/cirugía , Cuidados Paliativos/métodos , Adolescente , Adulto , Neoplasias de los Conductos Biliares/complicaciones , Neoplasias de los Conductos Biliares/secundario , Colestasis/etiología , Colestasis/cirugía , Drenaje/efectos adversos , Drenaje/instrumentación , Drenaje/mortalidad , Equinococosis Hepática/cirugía , Humanos , Cuidados Paliativos/instrumentación
19.
Chirurg ; 52(11): 728-31, 1981 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-7307688

RESUMEN

Since 1977, the Ender and Simon-Weidner nailing technique has been increasingly used at the Surgical University Clinic in Tübingen. This is an simple, gentle, low-risk procedure for surgical stabilization of pertrochanter femoral fractures and fractures of the lateral femoral neck in elderly people. Errors in external rotation are not always avoidable with this procedure, but they are tolerated with a lower surgical mortality than in the more complex method of osteosynthesis. Intraoperative complications are caused by faulty positioning, bad reposition of the fracture, false selection of the pinning site and nail length as well as insufficient splaying of the nails in the femoral head. Postoperative complications occur with distal as well as cranial displacement of the nails. Further complications are caused by placing a normal burden on the fracture too quickly and by the necessity of changing nails. Instructions will be given as to how these errors can be avoided.


Asunto(s)
Fracturas del Fémur/cirugía , Fracturas del Cuello Femoral/cirugía , Fijación Intramedular de Fracturas/métodos , Complicaciones Posoperatorias/prevención & control , Anciano , Humanos , Complicaciones Intraoperatorias/prevención & control , Infección de la Herida Quirúrgica/prevención & control
20.
Urologe A ; 38(4): 358-63, 1999 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-10444795

RESUMEN

Aim of this case-control study, performed on 412 male bladder cancer cases and 414 controls with benign prostatic hyperplasia in a former area of coal, iron and steel industries in Germany, was to identify occupations with an increased bladder cancer risk. In bladder cancer cases, smokers were overrepresented (58.3%) compared to controls (35.2%). The percentage of patients who had stopped smoking for at least 10 years did not differ in cases (10.2%) and controls (9.7%). Significantly elevated smoking-adjusted bladder cancer odds ratios (MH) were observed in painters and lacquers (MH 2.24, 95% CI 1.07-5.13), chemistry-related occupations (MH 2.44, 95% CI 1.05-5.67), coke plant workers (MH 2.89, 95% CI 1.16-7.16) and hard coal miners (MH 2.33, 95% CI 1.52-3.58). Significantly decreased smoking-adjusted bladder cancer odds ratios (MH) were observed in businessmen (MH 0.64, 95% CI 0.45-0.92) and office personnel (MH 0.58, 95% CI 0.41-0.81). In these two groups a relevant exposure to occupational bladder carcinogens is not likely.


Asunto(s)
Carcinoma de Células Transicionales/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Neoplasias de la Vejiga Urinaria/inducido químicamente , Anciano , Carcinoma de Células Transicionales/diagnóstico , Cocarcinogénesis , Humanos , Masculino , Enfermedades Profesionales/diagnóstico , Factores de Riesgo , Fumar/efectos adversos , Neoplasias de la Vejiga Urinaria/diagnóstico
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