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1.
Blood Cancer J ; 13(1): 181, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38065967

RESUMO

Multiple myeloma (MM) remains incurable despite the availability of novel agents. This multi-center retrospective cohort study used the Canadian Myeloma Research Group Database to describe real-world outcomes of patients withanti-CD38 monoclonal antibody (mAb) refractory MM subsequently treated with standard of care (SoC) regimens. Patients with triple class refractory (TCR) disease (refractory to a proteasome inhibitor, immunomodulatory drug, and anti-CD38 mAb) were examined as a distinct cohort. Overall, 663 patients had disease progression on anti-CD38 mAb therapy, 466 received further treatment (346 with SoC regimens were included, 120 with investigational agents on clinical trial and were excluded). The median age at initiation of subsequent SoC therapy of 67.9 (range 39.6-89.6) years with a median of 3 prior lines (range 1-9). The median PFS and OS from the start of subsequent therapy was 4.6 (95% CI 4.1-5.6) months and 13.3 (95% CI 10.6-16.6) months, respectively. The median PFS and OS of patients with TCR disease (n = 199) was 4.4 (95% CI 3.6-5.3) months and 10.5 (95% CI 8.5-13.8) months. Our results reinforce that real-world patients with relapsed MM, particularly those with TCR disease, have dismal outcomes. There remains an urgent unmet need for the development of and access to effective therapeutics for these patients.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Mieloma Múltiplo/tratamento farmacológico , Estudos Retrospectivos , Canadá/epidemiologia , Antineoplásicos/uso terapêutico , Receptores de Antígenos de Linfócitos T , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
3.
Eye (Lond) ; 27(6): 767-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23579405

RESUMO

PURPOSE: To ascertain the feasibility of pars plana vitrectomy (PPV) through a permanent Boston Keratoprosthesis type 1 (KPro) without the use of a temporary KPro. METHODS: A retrospective interventional case series. Eyes implanted with Boston KPro type 1 between 2008 and 2011 requiring PPV for vitreoretinal complications were included. Feasibility of PPV through the KPro, its anatomical and functional success were studied. RESULTS: Five out of 70 patients required PPV for vitreoretinal complications post-KPro surgery resulting in an incidence of 7%. PPV was feasible through the Boston KPro with no deleterious effects on the corneal carrier or the KPro itself. Repeat PPV was necessary in some cases. Although anatomical repair of the vitreoretinal complications was achieved in most cases, post PPV visual acuity remained poor in the majority. CONCLUSION: Our study suggests that although PPV through the Boston KPro is a viable approach for vitreoretinal disease repair, visual rehabilitation remains poor.


Assuntos
Próteses e Implantes , Doenças Retinianas/cirurgia , Vitrectomia/métodos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Implantação de Prótese/efeitos adversos , Estudos Retrospectivos , Acuidade Visual
4.
J Hazard Mater ; 166(2-3): 670-5, 2009 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-19223119

RESUMO

A study on laboratory scale to evaluate the environmental compatibility of electric arc furnace dust (EAFD) is reported in this article. EAFD, a waste by-product of the steel-making process, was generated on a steel plant located in Brazil. Different leaching tests, NBR10005 (Brazilian), AFNORX31-210 (French), JST-13 (Japanese), DIN38414-S4 (German), TCLP (American), and NEN 7343 (Netherland) were conducted. These leaching procedures are batch tests and are columns conducted in a way that an equilibrium condition should be achieved. The pH of the medium showed a crucial parameter governing the release of metals from the solid phase into solution. As the pH of the medium varies with the leachant used, this determines the dissolution of the elements. Zn, Pb, Mn, Cd, and Cu presented high leachability at NBR10005 procedures (acid pH). Except Pb and Cr, the leachability of all others metals in leaching tests with alkaline pH decreases with the increase of the pH. NBR10005 classifies the EAFD as a hazardous waste due to high concentration of Pb and Cd in leachate. The column tests are presented in the following order of leaching: Pb>Cr>Zn>Mn>Cu>Cd.


Assuntos
Resíduos Industriais/análise , Metais/isolamento & purificação , Aço , Poluentes Químicos da Água/isolamento & purificação , Brasil , Poeira , Substâncias Perigosas/análise , Substâncias Perigosas/isolamento & purificação , Concentração de Íons de Hidrogênio , Resíduos Industriais/prevenção & controle , Metalurgia/métodos , Metais/análise , Projetos Piloto , Poluentes Químicos da Água/análise
5.
Am J Ophthalmol ; 130(6): 834-5, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11124309

RESUMO

PURPOSE: To describe 2 cases of long-term successful clinical outcome after goniosynechialysis for secondary angle-closure glaucoma after vitreoretinal surgery. METHODS: Case reports. Goniosynechialysis was performed bilaterally in 1 patient and unilaterally in another for uncontrolled angle-closure glaucoma after vitreoretinal surgery. RESULTS: Angle reopening was performed 2 to 4 months after initial closure. After follow-up of between 3 and 5 years, intraocular pressure has remained below 21 mm Hg without medication in all three eyes. CONCLUSION: Goniosynechialysis should be considered a viable therapeutic alternative to filtration surgery in selected patients with a recent history of angle-closure glaucoma after vitreoretinal surgery.


Assuntos
Doenças da Córnea/cirurgia , Glaucoma de Ângulo Fechado/cirurgia , Doenças da Íris/cirurgia , Procedimentos Cirúrgicos Oftalmológicos , Recurvamento da Esclera/efeitos adversos , Vitrectomia/efeitos adversos , Idoso , Doenças da Córnea/etiologia , Feminino , Glaucoma de Ângulo Fechado/etiologia , Gonioscopia , Humanos , Pressão Intraocular , Doenças da Íris/etiologia , Masculino , Pessoa de Meia-Idade , Aderências Teciduais , Acuidade Visual
6.
J Biol Chem ; 273(28): 17573-8, 1998 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-9651351

RESUMO

A partial resistance to the growth inhibitory influence of 1, 25-dihydroxyvitamin D3 is apparent when immortalized keratinocytes are transformed by the ras oncogene. The vitamin D receptor (VDR) was isolated, analyzed, and found to be identical in normal, immortalized, and ras-transformed keratinocytes. Subsequently, nuclear extracts from immortalized and ras-transformed keratinocytes were analyzed in gel mobility shift assays utilizing labeled vitamin D response elements or thyroid hormone response elements. A specific protein.DNA complex that was shown to contain VDR using an anti-VDR antibody was identified in both types of extracts; however, the addition of an anti-retinoid X receptor (RXR) antibody identified RXR in the complex of both normal and immortalized keratinocyte cell extracts, but not in ras-transformed keratinocytes. Furthermore, transfection of ras-transformed keratinocytes with wild-type human RXRalpha rescued VDR.RXR and thyroid hormone receptor.RXR complexes as demonstrated by a supershift in the presence of the anti-RXR antibody. Both cell lines were found to express RXRalpha message in equal amounts. Western blot analysis revealed that RXRalpha protein from ras-transformed keratinocytes was indistinguishable from that from immortalized keratinocytes and from control cells. These results suggest a causal relationship between resistance to the growth inhibitory influences of 1,25-dihydroxyvitamin D3 and disruption of the VDR.RXR complex in malignant keratinocytes.


Assuntos
Transformação Celular Neoplásica/genética , Genes ras , Queratinócitos/metabolismo , Receptores de Calcitriol/metabolismo , Receptores do Ácido Retinoico/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Bases , Calcitriol/farmacologia , Linhagem Celular , Clonagem Molecular , DNA Complementar , Dimerização , Humanos , Oligodesoxirribonucleotídeos , Receptores do Ácido Retinoico/genética , Receptores X de Retinoides , Fatores de Transcrição/genética , Transcrição Gênica/efeitos dos fármacos
7.
Eur J Endocrinol ; 136(6): 640-8, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9225729

RESUMO

We examined the expression of parathyroid hormone-related peptide (PTHrP) and its receptor in normal newborn human calvaria osteoblastic (NHCO) cells. Northern blot analysis showed that NHCO cells express a single 1.6 kb transcript of PTHrP, which was increased within 1 h (2x) and peaked at 6 h (7x) after serum treatment. In the culture media, the release of PTHrP peptide was maximally increased (4x) 24 h after the addition of serum, as determined by immunoradiometric assay. NHCO cells exhibited a cytoplasmic immunostaining for PTHrP in the presence of serum, and most PTHrP-positive cells were alkaline phosphatase-negative, suggesting that PTHrP was expressed in undifferentiated cells. Furthermore, RT-PCR analysis showed that both PTHrP and PTH/PTHrP receptor were expressed in NHCO cells in basal conditions or after stimulation with serum. The maximal PTHrP expression induced by serum suppressed PTH/PTHrP receptor expression, suggesting that PTHrP down-regulated its receptor in NHCO cells. Treatment with 10 nM human PTH(1-34) which binds to PTH/PTHrP receptors, increased intracellular cAMP levels and alkaline phosphatase activity, and decreased cell growth, indicating that ligand binding to PTH/PTHrP receptors regulates NHCO cell proliferation and differentiation. The expression and synthesis of PTHrP and the presence of functional PTH/PTHrP receptors suggest a possible paracrine mechanism of action of PTHrP in normal human calvaria osteoblastic cells.


Assuntos
Osteoblastos/metabolismo , Proteínas/metabolismo , Receptores de Hormônios Paratireóideos/metabolismo , Crânio/metabolismo , Células Cultivadas , Humanos , Lactente , Recém-Nascido , Isomerismo , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/genética , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Hormônio Paratireóideo , Crânio/citologia
8.
J Biol Chem ; 271(27): 16310-6, 1996 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-8663213

RESUMO

Parathyroid hormone-related peptide (PTHRP) gene transcription is suppressed by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), the active metabolite of vitamin D3. In the present report, we examined 1, 25(OH)2D3-mediated repression of PTHRP expression by transfection of PTHRP promoter/reporter constructs in normal human keratinocytes and by DNA binding. We localized an element conferring 1, 25(OH)2D3-mediated repression in vivo to a 47-base pair (bp) region located -1121 to -1075 from the transcriptional start site. Mobility shift analysis revealed that this vitamin D response element (VDRE) forms DNA-protein complexes. The addition of a monoclonal antibody that recognizes the DNA binding region of the vitamin D receptor (VDR) attenuated binding of the receptor to the 47-bp sequence, whereas the addition of monoclonal antibody raised against the retinoid X receptor (RXR) further retarded the mobility of the protein-DNA complex. Consequently, the PTHRP promoter element binds a VDR.RXR heterodimer. Examination of this VDRE revealed complete sequence homology with a half-site of the human and rat osteocalcin VDRE (GGGTGA). Furthermore, mutation analysis suggests that a 16-bp domain consisting of an almost perfect repeat separated by a 3-base pair "spacer" GGGTGGAGAGGGGTGA is responsible for the DNA-protein interaction within this 47-bp sequence. Our results therefore indicate the existence of an inhibitory VDRE within the PTHRP promoter that is similar in sequence composition and cellular factor requirement to classical up-regulatory VDREs.


Assuntos
Calcitriol/farmacologia , Queratinócitos/metabolismo , Regiões Promotoras Genéticas , Biossíntese de Proteínas , Proteínas/genética , Sequências Reguladoras de Ácido Nucleico , Animais , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , Linhagem Celular , Células Cultivadas , Galinhas , Chlorocebus aethiops , Primers do DNA , Glutationa Transferase/biossíntese , Humanos , Queratinócitos/citologia , Cinética , Camundongos , Dados de Sequência Molecular , Proteína Relacionada ao Hormônio Paratireóideo , Reação em Cadeia da Polimerase , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Deleção de Sequência , Homologia de Sequência do Ácido Nucleico , Transfecção
9.
J Invest Dermatol ; 103(3): 323-9, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8077697

RESUMO

Calcium enhances keratinocyte differentiation, and 1,25 dihydroxyvitamin D3 (1,25(OH)2D3) is both antiproliferative and prodifferentiative in many cell types, including normal human keratinocytes. In the present study, we examined the combined effects of calcium and 1,25(OH)2D3 on parameters of growth and differentiation and on c-fos and p53 gene expression in normal human keratinocytes. Exposure of normal human keratinocytes to 1,25(OH)2D3 markedly reduced [3H] thymidine incorporation and cell number at low and high medium Ca++ concentrations. Simultaneously, cells in the G0/G1 phase of the cell cycle increased significantly and those in the S phase fell precipitously. 1,25(OH)2D3 and calcium also induced keratinocyte differentiation independently, as assessed by immunocytochemistry and by induction of involucrin mRNA. Both Ca++ and 1,25(OH)2D3 were shown, by nuclear run-on assays, to increase involucrin gene transcription. A rapid, transient elevation in c-fos protooncogene expression preceded these effects when epidermal growth factor was present alone. When 1,25(OH)2D3 was added to quiescent keratinocytes, there was a marked augmentation of c-fos mRNA accumulation at low and high medium Ca++ concentrations. Varying medium Ca++ concentrations had no effect on c-fos mRNA levels. Increasing medium Ca++ concentrations from 0.15 to 2.0 mM produced marked elevations of p53 mRNA accumulation and of the rate of p53 gene transcription, whereas 1,25(OH)2D3 had no effect. These results, therefore, suggest that 1,25(OH)2D3 and calcium act in concert to modulate the expression of two important cell-cycle-associated genes, which may be important components in the initial programming of growth and differentiation of normal human keratinocytes.


Assuntos
Calcitriol/farmacologia , Cálcio/farmacologia , Expressão Gênica/efeitos dos fármacos , Genes fos , Genes p53 , Queratinócitos/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Humanos , Queratinócitos/citologia , Queratinócitos/fisiologia , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Timidina/metabolismo , Transcrição Gênica/efeitos dos fármacos
10.
Am J Physiol ; 267(3 Pt 1): C723-30, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7943200

RESUMO

We have examined the expression and production of parathyroid hormone-related peptide (PTHRP) in primary cultures of normal human mammary epithelial cells (HMEC) derived from nonlactating breast tissue. In response to growth factors such as insulin, insulin-like growth factor I (IGF-I), and epidermal growth factor (EGF), immunoreactive PTHRP was released into conditioned medium, and PTHRP mRNA rapidly increased. In contrast, hydrocortisone and 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] inhibited these effects in a dose-dependent manner. Addition of prolactin (PRL) in the presence or absence of insulin, IGF-I, or EGF did not influence PTHRP production during the time course studied. To investigate whether these factors were acting at the transcriptional level, we performed nuclear run-on assays and demonstrated that IGF-I increased PTHRP gene transcription whereas hydrocortisone and 1,25(OH)2D3 inhibited this effect. These studies therefore demonstrate that IGF-I, EGF, 1,25(OH)2D3, and hydrocortisone modulate PTHRP expression in HMEC and that these effects occur in part at the level of gene transcription. Additionally, PRL, a known stimulator of PTHRP expression in vivo, has no effect in this in vitro model.


Assuntos
Mama/metabolismo , Proteínas/metabolismo , Mama/citologia , Calcitriol/farmacologia , Células Cultivadas , Células Epiteliais , Epitélio/metabolismo , Feminino , Substâncias de Crescimento/farmacologia , Hormônios/farmacologia , Humanos , Hidrocortisona/farmacologia , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/genética , RNA Mensageiro/metabolismo , Radioimunoensaio , Valores de Referência , Transcrição Gênica/efeitos dos fármacos
11.
Can J Ophthalmol ; 29(4): 182-6, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7994673

RESUMO

This prospective study was done to compare the efficacy of timolol and acetazolamide in lowering the intraocular pressure (IOP) secondary to the use of sodium hyaluronate (Healon) in cataract surgery. Fifty patients undergoing extracapsular cataract extraction and implantation of a posterior chamber lens were randomly assigned to one of four treatment groups: no viscoelastic (10 patients), Healon with 0.5% timolol drops postoperatively (12 patients), Healon with acetazolamide postoperatively (16 patients), or Healon only (12 patients). The IOP was measured during the first 24 hours after surgery. Sodium hyaluronate caused a marked increase in IOP in the early (6 to 12 hours) postoperative period. Timolol proved to be more effective than acetazolamide in controlling this pressure increase.


Assuntos
Acetazolamida/uso terapêutico , Extração de Catarata , Ácido Hialurônico/efeitos adversos , Pressão Intraocular/efeitos dos fármacos , Hipertensão Ocular/tratamento farmacológico , Timolol/uso terapêutico , Acetazolamida/administração & dosagem , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Lentes Intraoculares , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/induzido quimicamente , Soluções Oftálmicas , Complicações Pós-Operatórias , Estudos Prospectivos , Timolol/administração & dosagem
12.
Mol Endocrinol ; 8(2): 139-47, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8170470

RESUMO

We have used antisense RNA technology to inhibit endogenous PTH-related peptide (PTHRP) production in an established human keratinocyte cell line, HPK1A, to assess the role of PTHRP as a modulator of cell differentiation. Initially to determine the specificity of any alterations in cell function that might be observed, HPK1A cells and Rat-2 fibroblasts (which do not synthesize PTHRP) were both infected with the same retrovirus (pYN) containing antisense PTHRP. In contrast to antisense-infected HPK1A cells (HPK1A-AS), which show accelerated growth indices when endogenous PTHRP production is blocked, antisense-infected Rat-2 cells (Rat-2-AS) displayed no increase in cell proliferation. Consequently, this alteration in HPK1A cell function appeared to be specific to the inhibition of PTHRP production. In HPK1A-AS cells, no PTHRP transcript was observed in cytoplasmic RNA, and none was sequestered in a nuclear RNA preparation. Therefore, hybridization with the antisense strand appears to destabilize PTHRP mRNA, leading to rapid disappearance of the sense-antisense heteroduplex. We then examined the effect of PTHRP inhibition on keratinocyte differentiation using three indices. PTHRP inhibition in HPK1A-AS cells resulted in reduced high mol wt keratin production, as assessed by immunocytochemistry. Expression of mRNA encoding transglutaminase and involucrin was decreased in HPK1A-AS cells compared to that in control cells under conditions of high ambient calcium. Involucrin protein levels were also diminished in HPK1A-AS cells in parallel with the reduced levels of involucrin gene expression. These data, therefore, show that interference with PTHRP production inhibits expression of maturation-specific keratinocyte indices and indicate that endogenous PTHRP acts to enhance differentiation in this keratinocyte model.


Assuntos
Diferenciação Celular/fisiologia , Hormônio Paratireóideo/fisiologia , Proteínas/fisiologia , Animais , Linhagem Celular , Expressão Gênica/fisiologia , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Peso Molecular , Hormônio Paratireóideo/biossíntese , Proteína Relacionada ao Hormônio Paratireóideo , Biossíntese de Proteínas , Precursores de Proteínas/metabolismo , RNA Antissenso , Ratos , Ratos Endogâmicos F344
14.
Am J Ophthalmol ; 115(5): 623-8, 1993 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8488915

RESUMO

We examined ciprofloxacin levels in the aqueous humor, vitreous, or subretinal fluid in 40 patients undergoing cataract extraction, vitrectomy, or scleral buckling. Ciprofloxacin, 750 mg, was administered orally an average of 17 1/2 and 5 1/2 hours preoperatively. We obtained mean ciprofloxacin levels of 0.53 microgram/ml in aqueous humor, 0.51 microgram/ml in vitreous, and 0.71 microgram/ml in subretinal fluid. These vitreous levels exceed the minimum inhibitory concentration (MIC)90 of Staphylococcus epidermidis, Propionibacterium species, Pseudomonas aeruginosa, Proteus mirabilis, and Haemophilus influenzae, as well as the MIC70 of S. aureus and Bacillus cereus. Therefore, ciprofloxacin may have a role in the management and prevention of endophthalmitis.


Assuntos
Humor Aquoso/metabolismo , Ciprofloxacina/farmacocinética , Retina/metabolismo , Corpo Vítreo/metabolismo , Administração Oral , Bactérias/efeitos dos fármacos , Extração de Catarata , Ciprofloxacina/farmacologia , Endoftalmite/tratamento farmacológico , Endoftalmite/prevenção & controle , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Recurvamento da Esclera , Vitrectomia
15.
J Biol Chem ; 267(17): 12162-7, 1992 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-1318311

RESUMO

We have examined the effect of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on mitogen-stimulated growth and on c-myc proto-oncogene expression in a keratinocyte model of tumor progression. A dose-dependent inhibition of cell growth by 1,25-(OH)2D3 was demonstrated in both established (HPK1A) and malignant (HPK1A-ras) cells. However, this inhibition was observed with the addition of 1,25-(OH)2D3 at a higher concentration in HPK1A-ras cells than in HPK1A cells. Cell cycle analysis revealed a blockage of the normal progression of the cell cycle from G0 to S phase in the presence of 1,25-(OH)2D3. A higher concentration of 1,25-(OH)2D3 was required in HPK1A-ras cells to overcome the mitogen-stimulated progression into S phase, when compared with HPK1A cells. Analysis of c-myc messenger RNA revealed a strong inhibition of its expression at early time points with higher concentrations of 1,25-(OH)2D3 being required to obtain an inhibition in HPK1A-ras cells similar to that obtained in HPK1A cells. 1,25-(OH)2D3 receptor characterization by sucrose gradient analysis and equilibrium binding demonstrated the presence of a single 3.7 S protein with similar receptor numbers and affinity in both cell lines. These observations therefore demonstrate that an alteration of the growth inhibitory response to 1,25-(OH)2D3 occurs when keratinocytes acquire the malignant phenotype and suggest that the alteration lies beyond the interaction of the ligand with its receptor. In addition, relative resistance to 1,25-(OH)2D3 was also observed in the expression of the cell-cycle associated oncogene c-myc. These studies may therefore have important implications in vivo in the development and growth of epithelial cell cancers.


Assuntos
Calcitriol/farmacologia , Transformação Celular Neoplásica/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Animais , Northern Blotting , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Fator de Crescimento Epidérmico/farmacologia , Citometria de Fluxo , Genes myc , Humanos , Queratinócitos/citologia , Camundongos , Camundongos Nus , Proto-Oncogene Mas , RNA Mensageiro/metabolismo , Receptores de Calcitriol , Receptores de Esteroides/metabolismo
16.
Cancer Res ; 51(24): 6521-8, 1991 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-1742725

RESUMO

Using a human keratinocyte model of tumor progression, we have examined the regulation of gene expression and secretion of a parathyroid hormone-like peptide (PLP) that has been implicated in the pathogenesis of hypercalcemia in cancer. A rapid and transient induction of PLP mRNA in response to serum stimulation was demonstrated in both established (HPK1A) and malignant (HPK1A-ras) cells; however the dose dependent increases were greater in HPK1A than in HPK1A-ras. Significant inhibition of this induction was noted with the addition of 1,25-dihydroxyvitamin D3 at a lower concentration in HPK1A than in HPK1A-ras. Amino-terminal PLP immunoreactivity and bioactivity correlated well (r = 0.98) when measured in conditioned medium. In the absence of mitogenic stimuli, malignant keratinocytes (HPK1A-ras) secreted significantly more PLP than established (HPK1A) keratinocytes. However, in response to increasing concentrations of epidermal growth factor and fetal bovine serum, PLP release was far greater from HPK1A (maximum 13 x basal) than from HPK1A-ras (maximum 3 x basal) cells. In addition, 1,25-dihydroxyvitamin D3 was more effective in inhibiting both basal and stimulated PLP secretion in HPK1A than in HPK1A-ras cultures. Reduction of extracellular Ca2+ from 2.0 mM to 0.5 mM appeared to be more effective at an early time point in reducing PLP secretion from the established cells compared with the malignant cells. These studies therefore demonstrate a progressive dysregulation of PLP expression and secretion in human keratinocytes in the transformation from established to malignant phenotype and may have important implications for understanding the pathogenetic mechanisms involved in vivo in the development of hypercalcemia in cancer.


Assuntos
Queratinócitos/fisiologia , Proteínas de Neoplasias/genética , Neoplasias/genética , Proteínas/genética , Northern Blotting , Calcitriol/farmacologia , Cálcio/farmacologia , Células Cultivadas , Meios de Cultura , Fator de Crescimento Epidérmico/farmacologia , Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Neoplasias/patologia , Proteína Relacionada ao Hormônio Paratireóideo , RNA Mensageiro/genética , Fatores de Tempo
17.
Acta Ophthalmol (Copenh) ; 69(5): 603-10, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1776413

RESUMO

Computerized image processing was used to analyze color fundus photographs of 11 patients (22 eyes) with macular drusen who were followed for more than 2 years (mean follow-up, 4.7 years). Significant changes over time (more than +/- 20% of baseline area) were measured in the surface area of macular drusen in 18 of 22 (82%) eyes. An increase in the drusen area was associated significantly with eyes with mostly hard drusen and an initially smaller drusen area; but a decrease was associated with eyes with mostly soft drusen and an initially larger drusen area (P less than 0.01). The mean absolute rate of change in the drusen area was more than twice as great in eyes with mostly soft drusen compared with those with mostly hard drusen (P less than 0.05). All eye pairs studied showed a concomitant increase or decrease in the drusen area.


Assuntos
Processamento de Imagem Assistida por Computador , Drusas Retinianas/patologia , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Fundo de Olho , Humanos , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Fotografação , Reprodutibilidade dos Testes
18.
Exp Eye Res ; 52(2): 167-73, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2013299

RESUMO

The ocular hemodynamics in diabetic patients with increasingly severe retinopathy have been evaluated using a non-invasive computerized methodology. In a group of 19 healthy volunteers the mean ophthalmic arterial pressure and the ocular pulsatile blood flow were 83 +/- 2.4 mmHg and 648 +/- 42 microliters min-1 respectively. Nine diabetics with no apparent retinopathy had ophthalmic pressures and pulsatile blood flows similar to those in the control subjects. In 11 diabetic patients with background retinopathy the mean pulsatile blood flow was 471 +/- 70 microliters min-1. Thirteen diabetics with proliferative retinopathy had a pulsatile blood flow of 210 +/- 37 microliters min-1 and abnormally low ophthalmic arterial pressures. The results provide evidence that the choroidal blood flow decreases with the severity of the retinopathy in diabetes due to increased vascular resistance and a decreased ocular perfusion pressure.


Assuntos
Corioide/irrigação sanguínea , Retinopatia Diabética/fisiopatologia , Adulto , Pressão Sanguínea/fisiologia , Humanos , Pressão Intraocular/fisiologia , Pessoa de Meia-Idade , Artéria Oftálmica/fisiologia , Fluxo Pulsátil/fisiologia
19.
Ophthalmology ; 96(6): 801-10, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2662102

RESUMO

Proliferative vitreoretinopathy (PVR) is the leading cause of failure after retinal detachment surgery. Therefore, both the extracellular matrix and cellular components of preretinal membranes from 23 eyes with PVR were characterized immunohistochemically. The membrane stroma was composed primarily of types I, II, and III collagen. Laminin and both heparan sulfate proteoglycans and collagens types IV and V were co-distributed in discrete regions within the stroma. Glial and retinal pigment epithelial (RPE) cell populations were identified in these membranes using specific immunohistochemical markers as was a small but significant macrophage population. Double-labeling experiments indicated that RPE cells in these membranes expressed the class II histocompatibility antigen HLA-DR, although neither the RPE monolayer in situ nor cultured RPE cells was HLA-DR positive unless induced by gamma interferon. Only rare isolated vascular endothelial cells were detected in 5 of the 23 membranes.


Assuntos
Doenças Retinianas/imunologia , Colágeno/imunologia , Matriz Extracelular/imunologia , Imunofluorescência , Antígenos HLA-DR/imunologia , Heparitina Sulfato/imunologia , Humanos , Técnicas Imunoenzimáticas , Laminina/imunologia , Proteínas de Membrana , Epitélio Pigmentado Ocular/citologia , Epitélio Pigmentado Ocular/imunologia , Vitrectomia
20.
Arch Neurol ; 45(3): 353-6, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3341961

RESUMO

A 63-year-old man developed bilateral paresis of horizontal and upward eye movements. He was found to have a small oat cell carcinoma of the lung. Four months later he experienced acute visual blurring on the right side. Examination of the right eye at that time revealed a visual acuity of 3/200 and a central scotoma. There was swelling of the right optic disc. Three weeks after the onset of the visual loss, the acuity of the right eye spontaneously improved to 20/60, the field deficit lessened, and there was a decrease in the swelling of the optic disc. Subsequently, his neuro-ophthalmologic condition remained unchanged but his general health deteriorated, and he died nine months after the onset of the disease. Neuropathologic examination showed mild perivascular lymphocytic infiltration and fibrosis of the meninges throughout the central nervous system, loss of neurons and gliosis in the third and fourth cranial nerve nuclei, perivascular inflammation and gliosis of the optic nerves, and chiasm and central demyelination of the right optic nerve. No tumor cells were seen. These findings were consistent with a diagnosis of paraneoplastic optic neuritis and paraneoplastic encephalomyelitis. The present case confirms the existence of paraneoplastic optic neuritis and illustrates the clinical course of the disease.


Assuntos
Encefalomielite/complicações , Neurite Óptica/complicações , Síndromes Paraneoplásicas/complicações , Encefalomielite/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neurite Óptica/patologia , Síndromes Paraneoplásicas/patologia
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