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2.
J Am Acad Dermatol ; 45(5): 697-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11606918

RESUMO

BACKGROUND: UVA1 radiation seems to be effective in morphea. CD34+ dendritic cells are significantly decreased in lesional skin of morphea patients. OBJECTIVE: We evaluated the therapeutic effectiveness of medium-dose UVA1 phototherapy in localized scleroderma and its effect in the number of dermal CD34+ dendritic cells in skin biopsy specimens of these patients. METHOD: Patients were irradiated with UVA1 (30 J/cm(2)) 30 times. Dermal CD34+ dendritic cells were counted before and after therapy. RESULTS: There was clinical improvement after UVA1 irradiation. Dermal CD34+ dendritic cells significantly increased after UVA1 irradiation. CONCLUSION: Medium-dose UVA1 therapy is effective in the treatment of localized morphea. Effectiveness is associated with an increase in the number of CD34+ dendritic cells in the dermis.


Assuntos
Esclerodermia Localizada/terapia , Terapia Ultravioleta , Adulto , Antígenos CD34/análise , Células Dendríticas/imunologia , Feminino , Humanos , Masculino , Esclerodermia Localizada/imunologia , Esclerodermia Localizada/patologia , Resultado do Tratamento
3.
Br J Radiol ; 74(877): 77-82, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11227782

RESUMO

Radiation-induced loss of mouse brain endothelial cells has been examined in mice given an intravenous injection of the DNA-binding radioprotector Hoechst 33342 (80 mg kg-1). At the time of irradiation, 10 min after injection, Hoechst fluorescence in the brain was confined to the endothelial cells. Endothelial cell density was measured using a histochemical fluorescence technique that had been used previously to monitor post-irradiation changes in endothelial cell density in rat brain, in which it was shown that a sensitive subpopulation comprising about 15% of the endothelial cells was lost within 24 h of radiation exposure. The present study shows a similar dose-response for the control mice, with depletion of the sensitive subpopulation to 85% being almost complete after a dose of 2.5 Gy gamma-rays. However, in mice irradiated 10 min after Hoechst 33342 administration, doses between 12 Gy and 20 Gy were required to ablate these cells. The kinetics of cell loss and the rather large dose modification factor suggests that Hoechst 33342 may be suppressing an apoptotic response in this subpopulation. Whatever the mechanism involved, Hoechst 33342 clearly provides substantial protection against early radiation-induced endothelial cell loss. Further studies are necessary to determine the extent to which this initial protection translates into an improved long-term survival of the "protected" cells and, especially, to see whether this endothelial cell protection can ameliorate the later consequences of central nervous system irradiation, namely necrosis and paralysis.


Assuntos
Benzimidazóis/uso terapêutico , Encéfalo/efeitos da radiação , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/uso terapêutico , Animais , Encéfalo/citologia , Contagem de Células , Relação Dose-Resposta à Radiação , Endotélio/citologia , Endotélio/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Análise de Regressão
4.
Acta Oncol ; 39(6): 681-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11130004

RESUMO

The subcellular distribution and cytotoxicity of a DNA-binding ligand [125I]-Hoechst 33258 following incubation of K562 cells with the drug was investigated. The ability of a radical scavenger, dimethyl sulphoxide, to protect cells from the 125I-decay induced cell death was also studied. Three different concentrations and specific activities of the drug were used to provide different ligand : DNA binding ratios. The results demonstrated a trend toward improved delivery of the ligand to the nucleus and to chromatin at higher ligand concentrations, with concomitant increased sensitivity to 125I-decay induced cytotoxicity and decreased protection by dimethyl sulphoxide. This correlation of radiobiological parameters with subcellular drug distribution is consistent with the classical dogma that attributes cytotoxicity to DNA double-stranded breakage in the vicinity of the site of decay, where the high LET nature of the damage confers minimal sensitivity to radical scavenging.


Assuntos
Apoptose , Bisbenzimidazol/toxicidade , Dano ao DNA/genética , DNA de Neoplasias/genética , Corantes Fluorescentes/toxicidade , Radioisótopos do Iodo/toxicidade , Compostos Radiofarmacêuticos/toxicidade , Sítios de Ligação , DNA de Neoplasias/efeitos dos fármacos , Humanos , Células K562/efeitos dos fármacos , Ligantes
5.
Surg Clin North Am ; 80(2): 709-28, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10836013

RESUMO

The past century has been nearly all of the growth in knowledge about the anatomy and pathophysiology associated with cancers of the pancreas and surrounding biliary structures. Through advances in imaging technology, endoscopic practice, improvement in surgical technique and perioperative care, anesthesia advances, and a better appreciation for the usefulness of adjuvant chemotherapy and radiation therapy, physicians can offer patients some hope for long-term survival and a better quality of life when they are faced with these devastating tumors. Although surgical intervention is the "last best hope" for these patients, advances in the nonoperative disciplines will be required for substantial further improvement in patient outcomes.


Assuntos
Neoplasias do Sistema Biliar , Neoplasias Pancreáticas , Neoplasias do Sistema Biliar/diagnóstico , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/radioterapia , Neoplasias do Sistema Biliar/cirurgia , Quimioterapia Adjuvante , Colangiocarcinoma/terapia , Neoplasias da Vesícula Biliar/terapia , Humanos , Cuidados Paliativos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/cirurgia , Equipe de Assistência ao Paciente , Radioterapia Adjuvante
6.
Nucleic Acids Res ; 28(5): 1252-8, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10666470

RESUMO

The DNA photosensitisers m-iodo Hoechst and m-iodo, p-methoxy Hoechst have been co-crystallised with the oligonucleotide d(CGCGAATTCGCG)(2)and their crystal structures determined. The crystals were then subjected to slow dehydration, which reduced their solvent contents from 40 (normal) to 30 (partially dehydrated) and then 20% (fully dehydrated) and caused a reduction in cell volume from 68,000 to 60,000 then 51,000 A(3). The dehydration resulted in a dramatic enhancement of diffraction resolution from approximately 2.6 to beyond 1.5 A. Crystal structures have also been determined for the partially and fully dehydrated states. The fully dehydrated crystals consist of an infinite polymeric network, in which neighbouring dodecamer duplexes are crosslinked through phosphate oxygens via direct bonding to bridging magnesium cations. This unique three-dimensional structure for DNA is described in detail in the following companion paper. The present paper details evidence from the sequence of crystal structures that the DNA is able to breathe locally, allowing the ligand to leave the minor groove, re-orient in the surrounding solvent medium and then re-enter the groove in a different orientation and location. The rearrangement of the minor groove binding ligands during the dehydration process mimics the binding behaviour of these ligands in solution and in vivo. We also present details of the DNA-ligand interactions that are consistent with a hydrogen atom ion mechanism for photocleavage of DNA.


Assuntos
DNA/química , Desenho de Fármacos , Corantes Fluorescentes/química , Animais , Humanos , Conformação de Ácido Nucleico , Radiossensibilizantes/química
7.
Int J Radiat Oncol Biol Phys ; 42(4): 827-31, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9845105

RESUMO

PURPOSE: The aim of the study was to obtain evidence to support the hypothesis that the radioprotection by DNA-binding bibenzimidazoles is due to reduction by the DNA-bound ligand of transient radiation-induced oxidizing species on DNA, by following oxidation of the ligand after pulse radiolysis. A second aim was to compare the activities of methylproamine and Hoechst 33342 in the pulse radiolysis system, with the view to seeking a correlation with radioprotective activity. METHODS: Solutions of deoxyguanosine or DNA, with or without Hoechst 33342 or methylproamine, and containing sodium selenate and tert-butanol were subjected to pulse radiolysis, and the oxidation of the ligand followed by time-resolved spectrophotometry. RESULTS: The initial pulse radiolysis experiments using deoxyguanosine (dG) established that pulse radiolysis of sodium selenate produces a transient oxidant SeO3*-, which oxidizes dG to a species (presumably dG*+), with spectral characteristics indistinguishable from those described in previous pulse radiolysis studies using Br2*- as the oxidant. The estimate obtained for the bimolecular rate constant (k2) for the reaction of the selenite radical with dG, was 1.2 x 10(9) M(-1) s(-1). The corresponding reaction of SeO3*- with DNA is much slower (k2 3 x 10(7) M(-1) s(-1)). Although unbound Hoechst 33342 is oxidized directly by SeO3*- (k2 2.3 x 10(9) M(-1) s(-1)), experiments with mixtures of Hoechst 33342 with an excess of dG (or DNA) indicated that ligand oxidation was mediated by dG*+ (or DNAoxid). For example, successive dilution of a DNA-Hoechst solution had little impact on the rate of ligand oxidation, consistent with an intramolecular rate-determining step. When the concentration of DNA was maintained at 1.0 mM DNA bp, increasing the concentration of the ligand resulted in a linear increase in the rate of oxidation; the increase being steeper for methylproamine than for Hoechst 33342. Investigation of the dependence of yield of oxidized ligand on ligand occupancy also indicated that the methylproamine was more active than Hoechst 33342, with the estimates for the range of electron transfer from the ligand to DNAoxid being 14 and 31 bp for Hoechst 33342 and methylproamine, respectively. CONCLUSIONS: At this stage we conclude that radioprotection by these DNA-binding ligands is mediated by electron transfer, and that the improved radioprotective activity of methylproamine may be attributable to the observed kinetic differences. However, further studies are required to confirm the correlation, and if it is sustained, pulse radiolysis could be useful in evaluating new analogues in an attempt to further improve the radioprotective properties of methylproamine, which already has considerable clinical potential.


Assuntos
Benzimidazóis/farmacologia , DNA/farmacologia , Radiossensibilizantes/farmacologia , DNA/metabolismo , Elétrons , Radiólise de Impulso
8.
World J Surg ; 22(11): 1125-32, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9828720

RESUMO

The introduction of laparoscopic techniques for the management of biliary stone disease has expanded the therapeutic choices for surgeons confronted with choledocholithiasis. As new strategies emerge, the treatment of cholelithiasis and choledocholithiasis remains controversial. This paper discusses the options available for the treatment of common bile duct stones. Diagnostic and therapeutic algorithms are proposed. The treatment of these patients must be individualized, taking into consideration the condition of the patient, associated diseases, secondary complications of the gallstones, and the surgical expertise and resources of the institution.


Assuntos
Colecistectomia , Cálculos Biliares/cirurgia , Doença Aguda , Algoritmos , Colecistectomia Laparoscópica , Colecistite/complicações , Análise Custo-Benefício , Cálculos Biliares/complicações , Cálculos Biliares/diagnóstico , Infecções por HIV/complicações , Humanos , Imageamento por Ressonância Magnética/economia , Pancreatite/complicações
9.
Med Pediatr Oncol ; 31(2): 86-90, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9680932

RESUMO

BACKGROUND: The primary purpose of this descriptive study was to determine the long-term effects of cancer treatment in childhood on musculoskeletal function and gross motor skills. PROCEDURE: Musculoskeletal and gross motor function were assessed in a cohort of 36 survivors of acute lymphoblastic leukemia (ALL) seen in a pediatric tertiary care referral centre, compared to 36 age and gender matched comparison subjects. Basic gross motor skills were assessed using dimensions D: standing, and E: walking, running, and jumping of the Gross Motor Function Measure (GMFM). Strength, balance, and running speed and agility were assessed using the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP). Hand grip strength and ankle dorsiflexion range of motion were also measured. Findings in the children with ALL were compared by dependent (paired) t-tests to those in age and gender matched children. RESULTS: The GMFM scores for standing were 98.7% and for walking, running, and jumping were 99% of normal. The mean standard scores for the BOTMP were significantly lower than those of the comparison group: strength 11.5 vs. 19.4, balance 9.4 vs. 15.5, and running speed and agility 9.9 vs. 16.6. The ALL subjects had less hand grip strength 156.3 vs. 190.2, and less ankle dorsiflexion 7.5 vs. 16.1 degrees than the comparison group. The survivors of childhood leukemia were able to perform most basic gross motor functions. However, musculoskeletal impairment was evident and levels of motor proficiency were significantly poorer than those of age and gender matched children. CONCLUSIONS: Programs to promote physical activity and limit disability may improve gross motor function and increase overall quality-of-life in survivors of leukemia in childhood.


Assuntos
Antineoplásicos/efeitos adversos , Desenvolvimento Infantil/efeitos dos fármacos , Destreza Motora/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Fatores de Tempo
10.
Br J Cancer Suppl ; 27: S99-101, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8763857

RESUMO

Molecular studies on the mechanism of radioprotection by Hoechst 33342 have suggested that radioprotective activity might be improved by addition of electron-donating substituents to the ligand. This paper reports the results of experiments with proamine, in which the ethoxy group of Hoechst 33342 has been replaced with a dimethylamino group. Clonogenic survival studies with V79 cells confirmed the expectation of increased radioprotective activity of proamine. Also, proamine is less cytotoxic than Hoechst 33342, which further improves the extent of achievable radioprotection. The more general features of DNA-binding radioprotectors are also discussed in terms of their potential use in cancer radiotherapy. In particular it is proposed that the limited penetration of the compounds through cell layers might enable delivery to epithelial tissues by topical application, with limited access to the tumour via systemic uptake. In this context, the question of whether sufficient concentrations of such radioprotectors can be achieved in vivo has been addressed by experiments with the mouse lung model. In control animals, the ED50 for lethal loss of respiratory function at 16 weeks after irradiation was 19 Gy (single dose). Intravenous injection of Hoechst 33342 before irradiation extended the ED50 to 23 Gy.


Assuntos
Benzimidazóis/farmacologia , DNA/metabolismo , Protetores contra Radiação/farmacologia , Animais , Células Cultivadas , Cricetinae , Ligantes , Camundongos , Camundongos Endogâmicos DBA
11.
Arch Surg ; 131(3): 247-52, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8611088

RESUMO

OBJECTIVE: To assess the long-term outcome of patients following pylorus-preserving pancreatoduodenectomy (PPPD) for chronic pancreatitis. DESIGN: Retrospective study with mean follow-up of 63 months (range, 1 month to 13.7 years). SETTING: Tertiary referral hospital. PATIENTS: Records of all patients who underwent PPPD for chronic pancreatitis at Lahey Clinic were reviewed. All patients who were alive were contacted by telephone. In cases where patients had died, information was gathered from family members and hospital records. RESULTS: Forty-five patients underwent PPPD for disabling chronic pancreatitis. The mean preoperative duration of pain was 50 months, with 32 patients (70%) requiring daily narcotics. In one patient resection of the portal vein was required. One patient died within 30 days of the operation. Forty-one patients (92%) had improvement of pain at 5 years. The mean pain score (on a scale of 0 to 10) was 9.2 preoperatively and 1.5, 0.8, 1.1, and 1.1 at 6 months, 1 year, 2 years, and 5 years, respectively. Thirty-three patients (74%) had a postoperative weight gain to an average of 92% of their pre-illness weight. New-onset diabetes occurred in six patients (14%) by 6 months and in 21 patients (46%) by 5 years. Hypoglycemia was the cause of death in one patient who underwent total pancreatectomy. Four patients died of causes unrelated to PPPD. Marginal ulcers occurred in five patients (10%). Nine patients required late operations. CONCLUSIONS: In selected patients, resection of the head of the pancreas achieves long-term pain improvement in over 90% of cases. The early development of diabetes mellitus is infrequent, but over longer follow-up periods it reaches prevalence rates similar to those described in patients who have not undergone resection. Weight gain in this group was superior to that previously reported for our patients who underwent "standard Whipple" operation for chronic pancreatitis.


Assuntos
Pancreaticoduodenectomia , Pancreatite/cirurgia , Adulto , Idoso , Doença Crônica , Diabetes Mellitus/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Piloro , Encaminhamento e Consulta , Estudos Retrospectivos , Resultado do Tratamento
12.
Acta Oncol ; 35(7): 809-15, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9004757

RESUMO

The DNA breakage produced by decay of 125I in a double-stranded 41 bp oligodeoxynucleotide was investigated by DNA sequencing gel analysis. Use of both 5'- and 3'-end 32P labelling of the 125I containing strand provided the single-stranded breakage pattern at either side of the 125I-dC. The asymmetric pattern of breakage relative to the 125I-labelled nucleotide enabled deconvolution of two components of breakage. One of them declines very quickly with nucleotide number from 125I-dC and dominates within 4-5 nucleotides. We assume this component to be associated with neutralisation of charged Te atom resulted from decay, or/and with radiation damage to an initial target other than the deoxyribosyl moiety--probably the bases. The second component depends on the geometrical distance between the 125I atom and deoxyribosyl atoms. These two components are responsible for breakage under conditions limiting radical mediated damage, namely in the presence of 2M dimethylsulphoxide. The third component, associated with radical-mediated damage, contributes to the total breakage during incubation in 20 mM phosphate buffer alone, and under these incubation conditions dominates the breakage beyond 8-9 nucleotides from 125I-dC. The estimated average numbers of single-stranded breaks produced in the 125I-containing strand by each mechanism in 41-mer oligodeoxynucleotide with 125I-dC at 21st position are respectively 2.33, 0.98 and 0.63.


Assuntos
Dano ao DNA , DNA/efeitos da radiação , Radioisótopos do Iodo , Transferência Linear de Energia , Nucleotídeos/efeitos da radiação , DNA/efeitos dos fármacos , Dimetil Sulfóxido/farmacologia
13.
Acta Oncol ; 35(7): 803-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9004756

RESUMO

A double stranded oligodeoxynucleotide containing a single 125I-dC in a defined location was used to investigate DNA strand breakage resulting from 125I decay. Samples of a 41 bp oligodeoxynucleotide were incubated in 20 mM phosphate buffer (PB), or PB plus 2 M dimethylsulphoxide (DMSO), at 4 degrees C during 18-20 days. The 32P-5'-end labelled DNA fragments produced by 125I decays were separated on denaturing polyacrylamide gels, and the 32P activity in each fragment was determined by scintillation counting after elution of fragments from gel. Most of the breaks, around 90%, occurred within 4-5 nucleotides of the 125I-dC, but DNA breaks were detected up to 16 nucleotides from the decay site. The 125I-dC was located at the 21st nucleotide from the 32P-5'-end label, and since 32P was not detected in fragments longer than 20 nucleotides, it was assumed that all 125I decay events produce at least one break in the 125I-labelled DNA strand. The results show a considerable protection effect of DMSO on DNA breaks at sites >5-6 nucleotides from the 125I location. The probability of breaks in this region was decreased with DMSO by a factor of 2 to 8-fold, suggesting significant role for radical-mediated DNA breaks at the more distant sites. However, the total protection effect of DMSO is rather small: 1.1, because of the small contribution of breakage at distant sites to the total yield.


Assuntos
Dano ao DNA , DNA/efeitos da radiação , Desoxirribonucleotídeos , Radioisótopos do Iodo , Transferência Linear de Energia , Sequência de Bases/efeitos da radiação , DNA/efeitos dos fármacos , Dimetil Sulfóxido/farmacologia , Dados de Sequência Molecular
14.
Acta Oncol ; 35(7): 849-56, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9004762

RESUMO

We have analyzed a newly available high resolution and precision repeat of the original Martin and Haseltine experiment which includes the influence of DMSO on the results. The new model includes the production and diffusion of radical species and .OH radical attack on DNA as well as the direct hits. Calculations of single-strand breaks use individual Auger electron along with the tracks of electrons and radical species superimposed on an atomistic model of B-DNA. Comparison of the preliminary calculations with the experiment supports the earlier choice of data for the amount of energy required to produce a single-strand break, i.e. 17.5 eV. In a separate simulation we found that an average of less than two ionizations inducing a single-strand break gave the best fit to experimental data. Direct hits were found to be predominantly occurring at short range while the damage by .OH radicals was mainly of the long-range type.


Assuntos
DNA de Cadeia Simples/efeitos da radiação , Radioisótopos do Iodo/metabolismo , Transferência Linear de Energia , DNA de Cadeia Simples/metabolismo , Dimetil Sulfóxido/farmacologia , Radicais Livres/metabolismo , Radical Hidroxila/metabolismo , Método de Monte Carlo
16.
Arch Surg ; 130(4): 375-9; discussion 379-80, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7710335

RESUMO

OBJECTIVE: To assess the efficacy and safety of the removal of pancreatic duct stones by a combined modality approach in patients with pancreatic ductal lithiasis and recurrent abdominal pain. DESIGN: Retrospective review with a mean follow-up of 19 months (range, 1 to 56 months). SETTING: A tertiary care, private community hospital with a university affiliation. PATIENTS: The records of patients who presented to the hospital or who were referred with recurrent abdominal pain and who were demonstrated to have pancreatic ductal lithiasis between 1989 and 1994 were reviewed. Patients were assessed by their clinical response to pancreatic duct stone extraction by a variety of therapeutic interventions. RESULTS: Fifteen patients were included in the study. One patient was excluded from analysis because of a concurrent choledochocele. Two patients required operative decompression and stone extraction for endoscopically inaccessible stones. Six patients were treated with endoscopic management alone, and six were treated with a combination of extracorporeal shock wave lithotripsy and endoscopic stone retrieval. Twelve patients had complete clearance of the pancreatic duct. One patient had a stone that was not removed, but adequate pancreatic ductal decompression was achieved. The remaining patient had incomplete clearance of pancreatic stone fragments following extracorporeal shock wave lithotripsy but had adequate ductal drainage. No patient has required further therapy or hospitalization for abdominal pain. No complications occurred as a result of any intervention in this study. CONCLUSIONS: A multidisciplinary combined modality approach is a safe and effective method for extracting pancreatic duct stones in symptomatic patients. Stone extraction and reestablishment of adequate ductal drainage appear to relieve symptoms in some patients.


Assuntos
Cálculos/terapia , Ductos Pancreáticos , Dor Abdominal/etiologia , Dor Abdominal/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cálculos/complicações , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatopatias/complicações , Pancreatopatias/terapia , Recidiva , Estudos Retrospectivos
17.
Int J Dermatol ; 33(6): 418-20, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8056475

RESUMO

BACKGROUND: One-third of melanomas in Puerto Ricans occur on the skin of palms and soles. This is a study to define the characteristics of melanocytic nevi in those locations. METHODS: A sample of 1,039 patients were randomly examined for pigmented macules on the palms and soles. After informed consent, biopsies of these lesions were done on 67 patients. RESULTS: Among the patients, 13% were found to have pigmented macules on the palms and soles. Volar melanocytic macule was the most frequent lesion. CONCLUSIONS: Melanocytic nevi occur frequently on volar skin. The criteria for removal of these lesions should not be different from those lesions at other locations.


Assuntos
Doenças do Pé/epidemiologia , Mãos , Nevo Pigmentado/epidemiologia , Neoplasias Cutâneas/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Lentigo/epidemiologia , Masculino , Melanoma/epidemiologia , Pessoa de Meia-Idade , Nevo de Células Epitelioides e Fusiformes/epidemiologia , Nevo Pigmentado/congênito , Prevalência , Porto Rico/epidemiologia
18.
P R Health Sci J ; 13(2): 159-60, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7938403

RESUMO

This is the case of a 13 year-old female evaluated for a congenital skin lesion on the left buttock. Physical examination revealed a well-defined light brown patch with a 4mm papule on the center. A skin biopsy revealed an increased number of eccrine glands associated to a proliferation of vascular channels, particularly capillaries. These findings are consistent with a diagnosis of eccrine angiomatous hamartoma.


Assuntos
Glândulas Écrinas , Hemangioma Capilar/congênito , Neoplasias Cutâneas/congênito , Neoplasias das Glândulas Sudoríparas/congênito , Adolescente , Nádegas , Feminino , Humanos
19.
Int J Radiat Oncol Biol Phys ; 29(3): 549-53, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7516320

RESUMO

PURPOSE: To evaluate the importance of the position of the halogen atom in iodinated DNA-binding bibenzimidazoles, with respect to sensitization of UV-A-induced DNA breakage. METHODS AND MATERIALS: Three analogues of iodoHoechst 33258, denoted ortho-, meta- and paraiodoHoechst, according to the site of iodine substitution, were synthesized. Plasmid DNA (pBR322) was used to assay UV-A-induced DNA single-strand breaks (ssbs). The location of the sites of strand breakage was determined by DNA sequencing gel analysis, using a 32P-endlabelled oligoDNA with a single binding site for the ligands. RESULTS: A clear trend in decreasing activity of sensitization of UV-induced DNA ssbs was established: ortho- > meta-, para- > iodoHoechst 33258. The sequencing gel studies showed that orthoiodoHoechst was distinct from the other three compounds, with respect to the sites of DNA strand breakage and the chemistry of the cleavage reaction. CONCLUSION: The position of iodine substitution in iodinated bibenzimidazoles determines the location of the carbon-centered radical on the ligand in the minor groove of DNA. DNA strand cleavage is mediated by abstraction of a nearby deoxyribosyl H-atom. Hence, the position of the radical species determines: which deoxyribosyl group is attacked (i.e., site of cleavage relative to the ligand binding site); which H-atom is abstracted, more specifically which of the five deoxyribosyl carbons is involved (i.e., the chemistry of the cleavage reaction), and the stereochemistry of the transition state for the H-atom abstraction (and hence the efficiency or extent of strand breakage). The ortho-compound represents the best example to date of iodinated DNA ligands designed as potential radiation sensitizers, as an extension of the well-established sensitization by halogenated DNA precursors.


Assuntos
Bisbenzimidazol/metabolismo , Dano ao DNA , DNA/efeitos da radiação , Sequência de Bases , DNA/metabolismo , Ligantes , Dados de Sequência Molecular , Relação Estrutura-Atividade , Raios Ultravioleta
20.
Arch Surg ; 127(5): 536-8; discussion 538-9, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1374228

RESUMO

During a 2-year interval, we identified 10 patients with symptoms of pancreaticobiliary disorders and small choledochoceles by endoscopic retrograde cholangiopancreatography. Patients ranged from 36 to 89 years of age. Eight were female. Seven presented with recurrent, acute pancreatitis, two presented with biliary colic, and one presented with cholangitis. Dilated common bile ducts were seen in four patients, and no other biliary lesions were demonstrated in any patients. Five patients were shown to have normal gallbladders by ultrasonographic or computed tomographic criteria. Choledochoceles were identified endoscopically as a bulge above or involving the ampulla. Diagnosis was confirmed by cholangiography. All patients underwent successful unroofing of the choledochocele and sphincterotomy of the common bile duct. One pancreatic sphincterotomy was performed for pancreatic ductal obstruction. We encountered no complications. Hospital stays ranged from 1 to 4 days. Follow-up intervals ranged from 2 to 20 months. At this time, no patients have had any recurrence of symptoms, and none has required rehospitalization or surgery.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/normas , Cisto do Colédoco/terapia , Esfinterotomia Endoscópica/normas , Adulto , Idoso , Amilases/sangue , Colangiografia , Colangiopancreatografia Retrógrada Endoscópica/métodos , Cisto do Colédoco/classificação , Cisto do Colédoco/diagnóstico , Feminino , Seguimentos , Humanos , Tempo de Internação/estatística & dados numéricos , Lipase/sangue , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Recidiva , Esfinterotomia Endoscópica/métodos
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