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1.
J Eur Acad Dermatol Venereol ; 34(9): 2106-2110, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32078195

RESUMO

BACKGROUND: Few large studies have assessed spironolactone treatment of adult female acne. OBJECTIVES: To explore the role of spironolactone in the treatment of adult female acne. METHODS: We performed a retrospective case series assessing the efficacy of spironolactone treatment of a cohort of women evaluated at Mayo Clinic in Rochester, Minnesota, from 2007 through 2017. RESULTS: In total, 395 patients (median age, 32 years) received a median spironolactone dose of 100 mg daily. Approximately two-thirds of patients (66.1%) had a complete response; 85.1% had a complete response or a partial response greater than 50%. Median times to initial response and maximum response were 3 and 5 months. Efficacy was observed across all severity subtypes of acne, including those with papulopustular and nodulocystic acne. Patients received long-term treatment with spironolactone (median duration, 13 months) and had few adverse effects. CONCLUSIONS: Spironolactone is a safe and effective treatment of acne for women.


Assuntos
Acne Vulgar , Espironolactona , Acne Vulgar/tratamento farmacológico , Adulto , Feminino , Humanos , Minnesota , Estudos Retrospectivos , Resultado do Tratamento
4.
J Eur Acad Dermatol Venereol ; 25(1): 100-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20477930

RESUMO

BACKGROUND: Lichen planus is an autoimmune, inflammatory dermatosis of unknown cause that affects the skin and mucous membranes. OBJECTIVE: The aim of this study was to report the clinical features and response to therapy in a series of patients with ocular lichen planus. METHODS: A retrospective chart review was performed to identify patients with ocular lichen planus. Information about clinical presentation, treatment, and therapeutic response was extracted from the medical records. RESULTS: Eleven patients with ocular lichen planus were identified. The diagnosis was confirmed histologically for 10 patients. Nine patients were women. The average time from onset of ocular symptoms to diagnosis was 4.1 years. Eight patients had mucous membrane involvement at other sites. Disease was well controlled in eight patients. CONCLUSION: Lichen planus should be considered in the differential diagnosis of cicatricial conjunctivitis, especially when severe lichen planus is noted at other sites.


Assuntos
Cicatriz/complicações , Conjuntivite/patologia , Conjuntivite/terapia , Líquen Plano/patologia , Líquen Plano/terapia , Conjuntivite/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
5.
J Cell Physiol ; 182(3): 438-47, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10653611

RESUMO

The actin cytoskeleton plays an important role in the mediation of exocytosis and the determination of cell shape. Experimentally induced changes in cell shape have been shown to affect stimulated secretion in pancreatic acini. In this study, we have examined whether physiologic agonists induce changes in acinar cell shape to modulate secretion. Computer-enhanced video microscopy, immunofluorescence confocal microscopy, and quantitative Western blotting were used to study cell shape changes and cytoskeletal dynamics in rat pancreatic acini. Amylase assays were performed to study the effect of the actin-myosin cytoskeletal antagonists latrunculin A, BDM, and ML-9 on secretion. We found that pancreatic acini underwent a prominent and reversible shape change in response to the physiologic secretory agonist cholecystokinin. This was accompanied by an apical activation of myosin II as well as a basolateral redistribution of both actin and myosin II. Cytoskeletal antagonists inhibited this shape change and attenuated stimulated amylase secretion. Therefore, in addition to acting as a barrier at the apex, the actin-myosin cytoskeleton may also function to modulate cell shape to further regulate stimulated secretion.


Assuntos
Colecistocinina/farmacologia , Pâncreas/efeitos dos fármacos , Pâncreas/ultraestrutura , Actinas/análise , Actinas/metabolismo , Amilases/metabolismo , Animais , Azepinas/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Tamanho Celular/efeitos dos fármacos , Citocalasina D/farmacologia , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Diacetil/análogos & derivados , Diacetil/farmacologia , Inibidores Enzimáticos/farmacologia , Imunofluorescência , Masculino , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Vídeo , Cadeias Leves de Miosina/antagonistas & inibidores , Cadeias Leves de Miosina/metabolismo , Miosinas/metabolismo , Inibidores da Síntese de Ácido Nucleico/farmacologia , Pâncreas/metabolismo , Ratos , Ratos Sprague-Dawley , Tiazóis/farmacologia , Tiazolidinas
6.
J Cell Sci ; 111 ( Pt 19): 2911-22, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9730983

RESUMO

Suprastimulation of pancreatic acinar cells with specific agonists inhibits zymogen secretion and induces the formation of large basolateral blebs. Currently the molecular mechanisms that mediate this dramatic morphologic response are undefined. Further, it is unclear if blebbing represents a terminal or reversible event. Using computer-enhanced video microscopy of living acini we have found that these large blebs form rapidly (within 2-3 minutes) and exhibit ameboid undulations. They are induced by small increases in agonist concentration and require an energy-dependent phosphorylation event. Remarkably, the blebs are rapidly absorbed when agonist levels are reduced, indicating that blebbing is a reversible response to a physiological stimulus, not a terminal event. Morphological methods show that these dramatic changes in cell shape are accompanied by a marked reorganization of actin and myosin II at the basolateral domain. During 30 minutes of suprastimulation, both basolateral actin and myosin II gradually increase to form a ring centered at the necks of the blebs. Immunocytochemical and biochemical studies with a phospho-specific antibody to the myosin regulatory light chain reveal an activation of myosin II in suprastimulated acini that is completely absent in resting cells. Studies using cytoskeletal antagonistic drugs indicate that bleb formation and motility require actin remodeling concomitant with an activation of myosin II. This aberrant activation and reorganization of the actin-myosin cytoskeleton is likely to have detrimental effects on acinar cell function. Additionally, this mechanism of bleb formation may be conserved among other forms of physiological blebbing events.


Assuntos
Actinas/metabolismo , Citoesqueleto/metabolismo , Miosinas/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Tamanho Celular/efeitos dos fármacos , Colecistocinina/farmacologia , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/ultraestrutura , Técnicas In Vitro , Masculino , Microscopia Eletrônica de Varredura , Microscopia de Vídeo , Microtúbulos/efeitos dos fármacos , Microtúbulos/ultraestrutura , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/ultraestrutura , Fosforilação , Ratos , Ratos Sprague-Dawley , Sincalida/farmacologia
7.
Eur J Cell Biol ; 75(2): 140-52, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9548371

RESUMO

In secretory cells, microtubule- (Mt-) based motor enzymes are thought to support transport of secretory vesicles to the cell surface for subsequent release. At present, the role of Mts and kinesin in secretory vesicle transport in exocrine epithelial cells has not been defined. Furthermore, it is unclear whether an agonist-induced secretory event modifies kinesin function and distribution, thus altering vesicle transport. To this end, we utilized isolated rat pancreatic acini and cultured rat pancreatic acinar cells to examine the role of Mts and kinesin in regulated secretion. Exposure of cells to cytoskeletal antagonistic drugs demonstrated that the observed movements of apically clustered zymogen granules (ZGs) are supported by Mts, but not actin. Morphological studies of Mt organization in polarized acini show that Mt plus ends extend outward from the apical membrane toward the cell center. Immunofluorescence microscopy in both cell models revealed a clear association of kinesin with apical ZGs, while quantitative immunoblot analysis of pancreatic subcellular fractions confirmed kinesin enrichment on ZG membranes. In addition, microinjection of kinesin antibodies into cultured acinar cells inhibited ZG movements. Indirect immunofluorescence staining of isolated cells and quantitative Western blotting of isolated ZGs revealed that kinesin association with granule membranes increased up to 3-fold in response to a secretory stimulus. Autoradiographic studies of 32P-labeled acini showed up to a 6-fold increase in kinesin heavy chain (KHC) phosphorylation during stimulated secretion. These studies provide the first direct evidence that Mts and kinesin support ZG movements and that physiological agonists induce a marked phosphorylation of KHC while increasing the association of kinesin with ZG membranes. These changes during agonist stimulation suggest that the participation of kinesin in zymogen secretion is regulated.


Assuntos
Cinesinas/metabolismo , Pâncreas/metabolismo , Sequência de Aminoácidos , Animais , Células Cultivadas , Grânulos Citoplasmáticos , Precursores Enzimáticos/metabolismo , Microtúbulos/fisiologia , Dados de Sequência Molecular , Pâncreas/citologia , Fosforilação , Ratos , Ratos Sprague-Dawley , Secretina/farmacologia , Sincalida/farmacologia
8.
Vaccine ; 10(1): 3-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1371632

RESUMO

We seek to identify consensus sequences in digested fragments of antigenic proteins regulating selection and major histocompatibility complex (MHC)-restricted presentation to T cells of epitopes within those fragments. One such pattern, of recurrent, hydrophobic sidechains forming a longitudinal hydrophobic strip when a sequence is coiled as an alpha-helix, is found in or near most T cell-presented epitopes. Such recurrent hydrophobicity may lead to protease-protected coiling of the fragment against endosomal membranes and transfer to MHC molecules. This concept leads to better identification of T cell-presented sequences and possible to engineering of T cell-presented vaccines to affect their potency and MHC restriction.


Assuntos
Epitopos/química , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Fenômenos Químicos , Físico-Química , Humanos , Complexo Principal de Histocompatibilidade/imunologia , Dados de Sequência Molecular , Conformação Proteica
9.
Trends Biotechnol ; 9(7): 238-42, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1370048

RESUMO

The regular recurrence of hydrophobic amino acid residues along a peptide sequence determines the formation of a longitudinal hydrophobic strip when the peptide forms an alpha-helix. An understanding of the ways this may affect both folding of nascent proteins and antigen presentation should facilitate vaccine and therapeutics design.


Assuntos
Proteínas/imunologia , Sequência de Aminoácidos , Antígenos/imunologia , Sequência Consenso , Epitopos/imunologia , Dados de Sequência Molecular , Conformação Proteica , Proteínas/química , Linfócitos T/imunologia
10.
J Biol Chem ; 266(9): 5521-4, 1991 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-2005094

RESUMO

Helix formation in folding proteins is stabilized by binding of recurrent hydrophobic side chains in one longitudinal quadrant against the locally most hydrophobic region of the protein. To test this hypothesis, we fitted sequences of 247 alpha-helices of 55 proteins to the circular (infinite) template (symbol; see text) to maximize the strip-of-helix hydrophobicity index (the mean hydrophobicity of residues in (symbol; see text) positions). These template-predicted configurations closely matched crystallographic structures in 87% of four- or five-turn helices compared. We determined the longitudinal quadrant distributions of amino acids in the template-fitted, sheet projections of alpha-helices with respect to the best longitudinal, hydrophobic strip on each helix and to the N and C termini, interiors, and entire helices. Amino acids Leu, Ile, Val, and Phe were concentrated in one longitudinal quadrant (p less than 0.001). Lys, Arg, Asp, and Glu were not in the quadrant of Leu, Ile, Val, and Phe (p less than 0.001). Significant quadrant distributions for other amino acids and for termini of the helices were also found.


Assuntos
Aminoácidos , Conformação Proteica
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