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1.
J Exp Biol ; 222(Pt 20)2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31492818

RESUMEN

Holometabolous insects have been able to radiate to vast ecological niches as adults through the evolution of adult-specific structures such as wings, antennae and eyes. These structures arise from imaginal discs that show regenerative capacity when damaged. During imaginal disc regeneration, development has been shown to be delayed in the fruit fly Drosophila melanogaster, but how conserved the delay-inducing mechanisms are across holometabolous insects has not been assessed. The goal of this research was to develop the hornworm Manduca sexta as an alternative model organism to study such damage-induced mechanisms, with the advantage of a larger hemolymph volume enabling access to the hormonal responses to imaginal disc damage. Upon whole-body X-ray exposure, we noted that the imaginal discs were selectively damaged, as assessed by TUNEL and Acridine Orange stains. Moreover, development was delayed, predominantly at the pupal-to-adult transition, with a concomitant delay in the prepupal ecdysteroid peak. The delays to eclosion were dose dependent, with some ability for repair of damaged tissues. We noted a shift in critical weight, as assessed by the point at which starvation no longer impacted developmental timing, without a change in growth rate, which was uncoupled from juvenile hormone clearance in the body. The developmental profile was different from that of D. melanogaster, which suggests species differences may exist in the mechanisms delaying development.


Asunto(s)
Discos Imaginales/patología , Manduca/crecimiento & desarrollo , Nicotiana/parasitología , Animales , Peso Corporal/efectos de la radiación , Ecdisteroides/metabolismo , Cabeza , Discos Imaginales/efectos de la radiación , Hormonas Juveniles/metabolismo , Estadios del Ciclo de Vida/efectos de la radiación , Manduca/efectos de la radiación , Modelos Biológicos , Factores de Tiempo , Rayos X
2.
Am J Transplant ; 17(9): 2381-2389, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28199785

RESUMEN

Extending the functional integrity of renal allografts is the primary goal of transplant medicine. The development of donor-specific antibodies (DSAs) posttransplantation leads to chronic active antibody-mediated rejection (cAMR) and transplant glomerulopathy (TG), resulting in the majority of graft losses that occur in the United States. This reduces the quality and length of life for patients and increases cost. There are no approved treatments for cAMR. Evidence suggests the proinflammatory cytokine interleukin 6 (IL-6) may play an important role in DSA generation and cAMR. We identified 36 renal transplant patients with cAMR plus DSAs and TG who failed standard of care treatment with IVIg plus rituximab with or without plasma exchange. Patients were offered rescue therapy with the anti-IL-6 receptor monoclonal tocilizumab with monthly infusions and monitored for DSAs and long-term outcomes. Tocilizumab-treated patients demonstrated graft survival and patient survival rates of 80% and 91% at 6 years, respectively. Significant reductions in DSAs and stabilization of renal function were seen at 2 years. No significant adverse events or severe adverse events were seen. Tocilizumab provides good long-term outcomes for patients with cAMR and TG, especially compared with historical published treatments. Inhibition of the IL-6-IL-6 receptor pathway may represent a novel approach to stabilize allograft function and extend patient lives.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Rechazo de Injerto/tratamiento farmacológico , Antígenos HLA/inmunología , Isoanticuerpos/efectos adversos , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Receptores de Interleucina-6/antagonistas & inhibidores , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Supervivencia de Injerto/efectos de los fármacos , Supervivencia de Injerto/inmunología , Humanos , Inmunosupresores/uso terapéutico , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Pronóstico , Receptores de Interleucina-6/inmunología , Factores de Riesgo , Trasplante Homólogo
3.
Anticancer Res ; 44(4): 1791-1797, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537958

RESUMEN

BACKGROUND/AIM: Tumor-induced osteomalacia (TIO) is a rare pathology caused by overproduction of fibroblast growth factor 23 (FGF23). Its common clinical features include generalized muscle weakness, bone pain, and fractures. Complete resection of the offending tumor is the mainstay treatment. In this report, we present the first case of TIO by an FGF23 producing tumor treated using a tumor-bearing autograft treated with liquid nitrogen. CASE REPORT: A 63-year old female presented with generalized body pain, particularly in the left arm. The patient was diagnosed with a FGF23 producing tumor of the left humerus. Wide resection of the involved tumor was performed using a tumor-bearing autograft that was treated with liquid nitrogen. Postoperatively, the FGF23 and alkaline phosphatase (ALP) levels significantly decreased and inorganic phosphate normalized. There was also subsequent relief of generalized body pain. Immediately after the operation, range of motion of the left shoulder and elbow was initiated. The patient was instructed to perform forward flexion and abduction up to 90° with a rotational restraint. Almost complete bone union was observed at 12 months post procedure. Postoperative functional results were as follows: Musculoskeletal Tumor Society (MSTS) score of 27/30, 90% and International Society of Limb Salvage (ISOLS) score of 26/30, 87%. Ten years after the surgery, osteotomy line was completely obscured based on radiographs. The patient was disease free and without activity limitation. CONCLUSION: This is the first case report of wide excision of a FGF23 producing tumor and reconstruction using a tumor-bearing frozen autograft performed with excellent outcomes.


Asunto(s)
Osteomalacia , Síndromes Paraneoplásicos , Femenino , Humanos , Persona de Mediana Edad , Autoinjertos , Dolor , Nitrógeno
4.
Br J Cancer ; 109(7): 1744-9, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24022189

RESUMEN

BACKGROUND: The aging process is accompanied by physiological changes including reduced glomerular filtration and hepatic function, as well as changes in gastric secretions. To investigate what effect would aging have on the disposition of capecitabine and its metabolites, the pharmacokinetics between patients ≥70 years and <60 years were compared in SWOG0030. METHODS: Twenty-nine unresectable colorectal cancer patients were stratified to either ≥70 or <60 years of age, where the disposition of capecitabine and its metabolites were compared. RESULTS: Notable increase in capecitabine area under the curve (AUC) was accompanied by reduction in capecitabine clearance in ≥70 years patients (P<0.05). No difference in 5'-deoxy-5-fluorocytidine, 5'-deoxy-5-fluorouridine (DFUR), and 5-fluorouracil (5FU) AUCs between the two age groups, suggesting that carboxylesterase and cytidine deaminase (CDA) activity was similar between the two age groups. These results suggest that metabolic enzymes involved in converting capecitabine metabolites are not altered by age. An elevation in capecitabine Cmax and reduction in clearance was seen in females, where capecitabine AUC was 40.3% higher in women. Elevation of DFUR Cmax (45%) and AUC (46%) (P<0.05) was also noted, suggesting that CDA activity may be higher in females. CONCLUSION: Increases in capecitabine Cmax and AUC was observed in patients ≥70 years when compared with younger patients who were >60 years.


Asunto(s)
Antimetabolitos Antineoplásicos/sangre , Antimetabolitos Antineoplásicos/farmacocinética , Neoplasias Colorrectales/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Fluorouracilo/análogos & derivados , Factores de Edad , Anciano , Antimetabolitos Antineoplásicos/uso terapéutico , Área Bajo la Curva , Capecitabina , Neoplasias Colorrectales/metabolismo , Desoxicitidina/sangre , Desoxicitidina/farmacocinética , Desoxicitidina/uso terapéutico , Femenino , Floxuridina/sangre , Fluorouracilo/sangre , Fluorouracilo/farmacocinética , Fluorouracilo/uso terapéutico , Tasa de Filtración Glomerular , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Factores Sexuales
5.
Cancers (Basel) ; 15(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37568742

RESUMEN

Tumor-bearing frozen autografts have been widely used for reconstruction of bone defects caused by tumor resection. However, some patients undergo removal of the grafted bone due to surgical site infection, tumor recurrence, or fractures of the grafted bone. In this retrospective cohort study, predictive factors for graft survival were investigated in 123 patients who underwent reconstructions using a tumor-bearing frozen autograft after bone tumor resection of the extremities. To determine the independent predictors of graft survival, the association between various parameters and graft survival was investigated. The graft survival rates were 83.2% at 5 years and 70.2% at 10 years. Among the 123 frozen autografts, 25 (20.3%) were removed because of complications. In univariate analyses, male sex, BMI of ≥23.6, tibia, and chemotherapy were significantly associated with poor graft survival, whereas the pedicle/hemicortical freezing procedure was significantly associated with better graft survival. Multivariate analysis using the Cox proportional hazards regression model revealed that BMI of ≥23.6 (HR, 3.4; p = 0.005), tibia (HR, 2.3; p = 0.047), and freezing procedure (HR, 0.3; p = 0.016) were independently associated with graft survival. Based on the results, pedicle or hemicortical freezing techniques are recommended in cases where these techniques can be applied.

6.
Anticancer Res ; 43(5): 2127-2133, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37097658

RESUMEN

BACKGROUND/AIM: Amputation is still a viable option for musculoskeletal tumors that are multi-compartmental, adjacent to neurovascular structures, and involving pathological fractures. Complications such as poor surgical margins, local recurrence and infection after limb salvage surgery are also indications for secondary amputation. An effective hemostatic technique is vital for preventing complications of massive blood loss and prolonged operative time. The use of LigaSure™ in the field of musculoskeletal oncology has not been well documented. PATIENTS AND METHODS: This retrospective study included 27 patients with musculoskeletal tumor who underwent amputation using either LigaSure™ system (n=12) or traditional hemostatic technique (n=15) from 1999 to 2020. The purpose of this study was to evaluate the effect of LigaSure™ in terms of intra-operative blood loss, blood transfusion rates, and duration of surgery. RESULTS: The use of LigaSure™ resulted in a significant decrease in intraoperative blood loss (p=0.027) and blood transfusion rates (p=0.020). There was no significant difference for the duration of surgery between the two groups (p=0.634). CONCLUSION: The LigaSure™ system can potentially improve clinical outcomes in patients with musculoskeletal tumor undergoing amputation surgeries. The LigaSure™ system is a safe and effective hemostatic tool for musculoskeletal tumor amputation surgeries.


Asunto(s)
Neoplasias , Torniquetes , Humanos , Resultado del Tratamiento , Estudios Retrospectivos , Pérdida de Sangre Quirúrgica/prevención & control , Amputación Quirúrgica
7.
Trop Med Infect Dis ; 9(1)2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38251207

RESUMEN

Snail control to complement mass drug administration is being promoted by the World Health Organization for schistosomiasis control. Oncomelania hupensis quadrasi, the snail intermediate host of Schistosoma japonicum in the Philippines, has a very focal distribution; thus, scrutinizing baseline data and parameters affecting this distribution is very crucial. In this study in Gonzaga, Cagayan, Philippines, snail habitats were surveyed, and the various factors affecting the existence of the snails were determined. Malacological surveys and the mapping of sites of perpetual wetness in five endemic and five neighboring non-endemic barangays were conducted. Environmental and physicochemical factors were also examined. Maps of both snail and non-snail sites were generated. Of the fifty sites surveyed, O. h. quadrasi were found in twelve sites, and two sites yielded snails that were infected with S. japonicum cercariae. Factors such as silty loam soil, proximity to a snail site, water ammonia, and soil attributes (organic matter, iron, and pH) are all significantly associated with the presence of snails. In contrast, types of habitats, temperatures, and soil aggregation have no established association with the existence of snails. Mapping snail sites and determining factors favoring snail presence are vital to eliminating snails. These approaches will significantly maximize control impact and minimize wasted efforts and resources, especially in resource-limited schistosomiasis endemic areas.

8.
Lancet Respir Med ; 11(12): 1075-1088, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37979588

RESUMEN

BACKGROUND: The live-attenuated influenza virus vector-based intranasal SARS-CoV-2 vaccine (dNS1-RBD, Pneucolin; Beijing Wantai Biological Pharmacy Enterprise, Beijing, China) confers long-lasting and broad protection in animal models and is, to our knowledge, the first COVID-19 mucosal vaccine to enter into human trials, but its efficacy is still unknown. We aimed to assess the safety and efficacy (but not the immunogenicity) of dNS1-RBD against COVID-19. METHODS: We did a multicentre, randomised, double-blind, placebo-controlled, adaptive design, phase 3 trial at 33 centres (private or public hospitals, clinical research centres, or Centre for Disease Control and Prevention) in four countries (Colombia, Philippines, South Africa, and Viet Nam). Men and non-pregnant women (aged ≥18 years) were eligible if they had never been infected with SARS-CoV-2, and if they did not have a SARS-CoV-2 vaccination history at screening or if they had received at least one dose of other SARS-CoV-2 vaccines 6 months or longer before enrolment. Eligible adults were randomly assigned (1:1) to receive two intranasal doses of dNS1-RBD or placebo administered 14 days apart (0·2 mL per dose; 0·1 mL per nasal cavity), with block randomisation via an interactive web-response system, stratified by centre, age group (18-59 years or ≥60 years), and SARS-CoV-2 vaccination history. All participants, investigators, and laboratory staff were masked to treatment allocation. The primary outcomes were safety of dNS1-RBD in the safety population (ie, those who had received at least one dose of dNS1-RBD or placebo) and efficacy against symptomatic SARS-CoV-2 infection confirmed by RT-PCR occurring 15 days or longer after the second dose in the per-protocol population (ie, those who received two doses, were followed up for 15 days or longer after the second dose, and had no major protocol deviations). The success criterion was predefined as vaccine efficacy of more than 30%. This trial is registered with the Chinese Clinical Trial Registry (ChiCTR2100051391) and is completed. FINDINGS: Between Dec 16, 2021, and May 31, 2022, 41 620 participants were screened for eligibility and 31 038 participants were enrolled and randomly assigned (15 517 in the vaccine group and 15 521 in the placebo group). 30 990 participants who received at least one dose (15 496 vaccine and 15 494 placebo) were included in the safety analysis. The results showed a favourable safety profile, with the most common local adverse reaction being rhinorrhoea (578 [3·7%] of 15 500 vaccine recipients and 546 [3·5%] of 15 490 placebo recipients) and the most common systemic reaction being headache (829 [5·3%] vaccine recipients and 797 [5·1%] placebo recipients). We found no differences in the incidences of adverse reactions between participants in the vaccine and placebo groups. No vaccination-related serious adverse events or deaths were observed. Among 30 290 participants who received two doses, 25 742 were included in the per-protocol efficacy analysis (12 840 vaccine and 12 902 placebo). The incidence of confirmed symptomatic SARS-CoV-2 infection caused by omicron variants regardless of immunisation history was 1·6% in the vaccine group and 2·3% in the placebo group, resulting in an overall vaccine efficacy of 28·2% (95% CI 3·4-46·6), with a median follow-up duration of 161 days. INTERPRETATION: Although this trial did not meet the predefined efficacy criteria for success, dNS1-RBD was well tolerated and protective against omicron variants, both as a primary immunisation and as a heterologous booster. FUNDING: Beijing Wantai Biological Pharmacy Enterprise, National Science and Technology Major Project, National Natural Science Foundation of China, Fujian Provincial Science and Technology Plan Project, Natural Science Foundation of Fujian Province, Xiamen Science and Technology Plan Special Project, Bill & Melinda Gates Foundation, the Ministry of Education of China, Xiamen University, and Fieldwork Funds of Xiamen University.


Asunto(s)
COVID-19 , Vacunas Virales , Adulto , Masculino , Femenino , Humanos , Adolescente , Adulto Joven , Persona de Mediana Edad , Vacunas contra la COVID-19/efectos adversos , SARS-CoV-2 , COVID-19/prevención & control , Método Doble Ciego
9.
J Exp Med ; 144(5): 1243-53, 1976 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-186553

RESUMEN

Some human marrows in culture release particles with oncornavirus-like properties. This study was designed to examine the immunological properties of similar particles in human marrow culture supernates. Leukemic and nonleukemic marrows were cultured for 5-7 days in the presence of [14C]uridine and [3H]leucine or [3H]glucosamine. Labeled supernatant components banding in sucrose gradient densities of 1.20-1.24 g/ml were used as antigen in a double antibody immunoprecipitation assay. The assay was validated by end point titrations and competition with unlabeled antigen; purified myeloma proteins were used as negative controls. Cross-reactivity with mammalian oncornaviruses, as judged by competitive inhibition of precipitation by these viruses, was slight and at the border of the sensitivity of the method. Precipitated antigens analyzed by SDS polyacrylamide gel electrophoresis contained three distinct polypeptides of about 70,000, 45,000 and 30,000 mol wt; these comigrated with the gp 70, pg 45, and p 30 of a murine leukemia virus. Similar polypeptides were obtained from both leukemic and nonleukemic marrow culture supernates. As determined by the radioimmunoprecipitation assay, 32 of 45 leukemic sera (71%), 36 of 45 normal sera (80%), 15 of 19 sera from family contacts of leukemic patients (79%), 14 of 21 cord blood specimens (67%), and 21 of 23 sera (91%) from patients with systemic lupus erythematosus had detectable antibody activity.


Asunto(s)
Anticuerpos Antivirales/análisis , Células de la Médula Ósea , Médula Ósea/microbiología , Proteínas Virales/aislamiento & purificación , Reacciones Cruzadas , Gammaretrovirus/inmunología , Humanos , Leucemia/microbiología , Proteínas Virales/inmunología
10.
Science ; 269(5226): 966-7, 1995 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-17807732

RESUMEN

The successful synthesis of pure boron nitride (BN) nanotubes is reported here. Multi-walled tubes with inner diameters on the order of 1 to 3 nanometers and with lengths up to 200 nanometers were produced in a carbon-free plasma discharge between a BN-packed tungsten rod and a cooled copper electrode. Electron energy-loss spectroscopy on individual tubes yielded B:N ratios of approximately 1, which is consistent with theoretical predictions of stable BN tube structures.

11.
J Nutr Biochem ; 69: 1-9, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31035100

RESUMEN

Folate-dependent one-carbon cycle metabolism (FOCM) plays a critical role in maintaining genomic stability through regulating DNA biosynthesis, repair and methylation. Folate metabolites as well as other metabolites in the FOCM are hypothesized to be altered when cells transition from normal to cancerous state. Using cells at different stages in their development into colorectal cancer, the FOCM metabolites were profiled as an effort to phenotype the cells, and the metabolite levels were compared to the expressions of related genes. Here, we investigate whether there is a correlation between the metabolite levels, DNA methylation levels and the expression of the related genes that drive the levels of these metabolites. Using CRL1459, APC10.1, HCT116 and Caco-2, we show for the first time that FOCM metabolites correlate with the gene expression patterns. These differences follow a trend that may facilitate distinguishing colon cells at the different stages as they transition into cancerous state. The folate distribution and methionine levels were found to be key in determining the staging of the colon cells in CRC development. Also, expression of CBS, MTRR and MAT genes may facilitate distinguishing between untransformed and transformed colon cells.


Asunto(s)
Carbono/metabolismo , Colon/patología , Ácido Fólico/metabolismo , Células CACO-2 , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Transformación Celular Neoplásica , Colon/citología , Colon/metabolismo , Metilación de ADN , Ferredoxina-NADP Reductasa/genética , Receptor 1 de Folato/genética , Ácido Fólico/genética , Ácido Fólico/farmacología , Regulación de la Expresión Génica , Glicina Hidroximetiltransferasa/genética , Células HCT116 , Humanos
12.
Pathogens ; 8(4)2019 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-31547610

RESUMEN

BACKGROUND: The perpetuation of schistosomiasis japonica in the Philippines depends to a major extent on the persistence of its intermediate host Oncomelania hupensis quadrasi, an amphibious snail. While the malacological survey remains the method of choice in determining the contamination of the environment as evidenced by snails infected with schistosome larval stages, an emerging technology known as environmental DNA (eDNA) detection provides an alternative method. Previous reports showed that O. hupensis quadrasi eDNA could be detected in water, but no reports have been made on its detection in soil. METHODS: This study, thus focused on the detection of O. hupensis quadrasi eDNA from soil samples collected from two selected schistosomiasis-endemic barangays in Gonzaga, Cagayan Valley using conventional and TaqMan-quantitative (qPCR) PCRs. RESULTS: The results show that qPCR could better detect O. hupensis quadrasi eDNA in soil than the conventional method. In determining the possible distribution range of the snail, basic edaphic factors were measured and correlated with the presence of eDNA. The eDNA detection probability increases as the pH, phosphorous, zinc, copper, and potassium content increases, possibly indicating the conditions in the environment that favor the presence of the snails. A map was generated to show the probable extent of the distribution of the snails away from the body of the freshwater. CONCLUSION: The information generated from this study could be used to determine snail habitats that could be possible hotspots of transmission and should, therefore, be targeted for snail control or be fenced off from human and animal contact or from the contamination of feces by being a dumping site for domestic wastes.

13.
Nat Commun ; 9(1): 4559, 2018 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-30455465

RESUMEN

Epigenetic regulators are attractive anticancer targets, but the promise of therapeutic strategies inhibiting some of these factors has not been proven in vivo or taken into account tumor cell heterogeneity. Here we show that the histone methyltransferase G9a, reported to be a therapeutic target in many cancers, is a suppressor of aggressive lung tumor-propagating cells (TPCs). Inhibition of G9a drives lung adenocarcinoma cells towards the TPC phenotype by de-repressing genes which regulate the extracellular matrix. Depletion of G9a during tumorigenesis enriches tumors in TPCs and accelerates disease progression metastasis. Depleting histone demethylases represses G9a-regulated genes and TPC phenotypes. Demethylase inhibition impairs lung adenocarcinoma progression in vivo. Therefore, inhibition of G9a is dangerous in certain cancer contexts, and targeting the histone demethylases is a more suitable approach for lung cancer treatment. Understanding cellular context and specific tumor populations is critical when targeting epigenetic regulators in cancer for future therapeutic development.


Asunto(s)
Progresión de la Enfermedad , Histona Demetilasas/metabolismo , Histona Metiltransferasas/metabolismo , Neoplasias Pulmonares/metabolismo , Adenocarcinoma del Pulmón/metabolismo , Animales , Carcinogénesis , Línea Celular Tumoral/efectos de los fármacos , Supervivencia Celular , Modelos Animales de Enfermedad , Matriz Extracelular/genética , Histona Demetilasas/efectos de los fármacos , N-Metiltransferasa de Histona-Lisina/efectos de los fármacos , N-Metiltransferasa de Histona-Lisina/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Organoides/anatomía & histología , Fenotipo , Proteínas Proto-Oncogénicas p21(ras)/genética
14.
J Clin Invest ; 73(6): 1731-9, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6725557

RESUMEN

A single-chain 55,000-mol wt form of urokinase (UK), similar to that previously isolated from urine, was purified from a transformed kidney cell culture medium and characterized; and its fibrinolytic properties were evaluated. The preparation immunoprecipitated with UK antiserum, had a low intrinsic amidolytic activity that was 0.1% of its active derivative, and resisted diisopropyl fluorophosphate treatment and inactivation by plasma inhibitors. The single-chain UK was therefore designated pro-UK. In the presence of plasmin and during clot lysis, activation by conversion to two-chain, 55,000-mol wt UK (TC-UK) was demonstrated. This did not occur during blood clotting nor on incubation with purified thrombin. Clot lysis in plasma consistently occurred in 2-5 h with 50-100 IU per ml of pro-UK, whereas comparable lysis was inconsistently achieved by 500-1,000 IU of UK. Pro-UK, in sharp contrast to UK, caused no fibrinogen degradation at fibrinolytic concentrations. In the absence of a clot, pro-UK in plasma was stable for more than 2 d. When a clot was added after incubation (37 degrees C) for 50 h, activation to full lytic activity took place. The findings in vivo were comparable but the rapid clearance of pro-UK required that it be given by a constant infusion despite its plasma stability. In rabbits, a UK-resistant species, pro-UK was significantly (P less than 0.001) more efficacious than TC-UK but neither induced significant fibrinogen degradation. In dogs, a more sensitive species, the high specificity of thrombolysis by pro-UK contrasted with the defibrinogenation and uncontrollable bleeding that accompanied thrombolysis by UK. It was concluded that clot lysis by pro-UK is more effective and specific than UK. The advantage of pro-UK is in the limitation of its activation to the site of a clot. This can be explained by an activation mechanism that is dependent, under physiological conditions, on fibrin-stabilized plasmin.


Asunto(s)
Precursores Enzimáticos/metabolismo , Fibrina/metabolismo , Fibrinólisis , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Animales , Perros , Electroforesis en Gel de Poliacrilamida , Precursores Enzimáticos/aislamiento & purificación , Fibrinógeno/análisis , Humanos , Cinética , Peso Molecular , Oxidación-Reducción , Conejos , Especificidad de la Especie , Activador de Plasminógeno de Tipo Uroquinasa/aislamiento & purificación
15.
J Natl Cancer Inst ; 55(3): 691-8, 1975 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-169383

RESUMEN

The incidence of infectious murine leukemia virus (MuLV) in congenic-resistant C57BL mice was studied. No constant relationship between the incidence of MuLV and the H-2 complex was apparent. Two lines, B10 and B10.A, were examined in detail because the incidence of MuLV in B10 was low and the virus appeared relatively late in life, whereas B10.A animals had a relatively high incidence of infection by MuLV early in life. Further studies of B10.A mice revealed an almost universal concordance between the virologic status of the mother and her offspring. This was particularly evident when (B10 times B10.A)F1 animals were compared with (B10.A times B10)F1 mice: Although genetically identical, the incidence of MuLV in the latter was high, whereas in the former it was low. Transmission of MuLV by milk was proved by foster-nursing experiments; when the infants of MuLV-positive B10.A mothers were suckled on MuLV-negative B10.A mothers, they were free of MuLV. Milk-borne infection may account for the natural dissemination of MuLV among some inbred lines of mice.


Asunto(s)
Virus de la Leucemia Murina , Leche/microbiología , Infecciones Tumorales por Virus/transmisión , Animales , Genotipo , Antígenos de Histocompatibilidad , Virus de la Leucemia Murina/aislamiento & purificación , Ratones , Ratones Endogámicos AKR , Ratones Endogámicos C57BL , Bazo/microbiología , Infecciones Tumorales por Virus/genética , Ensayo de Placa Viral
16.
J Natl Cancer Inst ; 89(23): 1797-802, 1997 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-9392621

RESUMEN

BACKGROUND: In vitro and in vivo clinical studies have shown that certain preparations of human chorionic gonadotropin have antitumor activity against Kaposi's sarcoma, the most common tumor in patients infected with human immunodeficiency virus type 1 (HIV-1). METHODS: A phase I trial was conducted in 18 male patients with acquired immunodeficiency syndrome-related Kaposi's sarcoma. Successive cohorts of six patients each received human chorionic gonadotropin (A.P.L.; Wyeth-Ayerst, Radnor, PA) subcutaneously at doses of 5000 IU daily (level I), 10,000 IU three times a week (level II), or 10,000 IU daily (level III). Toxic effects, changes in reproductive hormone levels, HIV-1 RNA plasma levels, and response to therapy were evaluated. RESULTS: A.P.L. treatment was well tolerated at all dose levels, and no maximum-tolerated, dose-defined toxic effects were observed at the highest dose tested. The most common side effects were weight gain, increased libido, and increased energy. A persistent increase in testosterone level and a persistent decline in luteinizing hormone and follicle-stimulating hormone levels were seen over time. Major responses were observed in six patients. Partial remissions (> or =50% decrease in lesion numbers, volume, or surface area) were observed at dose level I and dose level II (two patients each); biopsy-confirmed complete remissions (resolution of all lesions) were observed at dose level III (two patients). All but one major response have persisted from 207 to more than 515 days. Nine patients had stable disease lasting 10 weeks or longer. CONCLUSIONS: A.P.L. given at daily doses ranging from 5000 to 10,000 IU has antitumor activity in patients with acquired immunodeficiency syndrome-related Kaposi's sarcoma. A.P.L. can be given for more than 1 year with minimal side effects. Larger efficacy studies are warranted.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Antineoplásicos/uso terapéutico , Gonadotropina Coriónica/uso terapéutico , Sarcoma de Kaposi/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Adulto , Antineoplásicos/administración & dosificación , Gonadotropina Coriónica/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Sarcoma de Kaposi/virología , Neoplasias Cutáneas/virología , Resultado del Tratamiento
17.
Clin Pharmacol Ther ; 100(5): 419-422, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27500791

RESUMEN

The American Association of Pharmaceutical Scientists/International Transporter Consortium Joint Workshop on Drug Transporters in absorption, distribution, metabolism, and excretion was held with the objective of discussing innovative advances in transporter pharmacology. Specific topics included (i) transporters at the blood-brain barrier (BBB); (ii) emerging transport proteins; (iii) recent advances in achieving hepatoselectivity and optimizing clearance for organic anion-transporting polypeptide (OATP) substrates; (iv) utility of animal models for transporter studies; and (v) clinical correlation of transporter polymorphisms. Here, we present state-of-the-art highlights from this workshop in these key areas of focus.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Modelos Animales , Transportadores de Anión Orgánico/metabolismo , Animales , Humanos , Proteínas de Transporte de Membrana/genética , Estados Unidos
18.
Oncogene ; 19(52): 5982-7, 2000 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-11146549

RESUMEN

The steroid hormone, estradiol, is essential for both the growth of normal breast and induction of mammary carcinomas. The growth promoting effects of estrogen are presumed to be mediated by growth factors, in particular, epidermal growth factor, which mediates its effects through erbB receptors, erbB1 and erbB2/C-neu. C-neu is amplified and over-expressed in a large number of human cancers and transgenic mice over-expressing C-neu also develop mammary tumors. However, as yet, the impact of C-neu over-expression on estrogen action during normal mammary development and hence, its precise role in carcinogenesis, remains unclear. In the present studies, we demonstrate that estradiol-dependent mammary ductal growth accompanying puberty is impaired in transgenic mice expressing wild type Cneu, and is intrinsic to the tissue. The impairment is not due to an overall impairment in estrogen action, since progesterone receptor expression is unaffected in C-neu mice. It is also not due to an intrinsic inability of the epithelial cells to proliferate, since impeded ductal growth co-exists with alveolar growth during pregnancy. Therefore, we propose that, depending on the physiological state, C-neu may either promote or inhibit the growth of mammary epithelial cells, and discuss its potential significance to carcinogenesis.


Asunto(s)
Glándulas Mamarias Animales/crecimiento & desarrollo , Receptor ErbB-2/genética , Receptor ErbB-2/fisiología , Envejecimiento/fisiología , Animales , División Celular/efectos de los fármacos , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/trasplante , Estradiol/farmacología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Glándulas Mamarias Animales/efectos de los fármacos , Glándulas Mamarias Animales/metabolismo , Glándulas Mamarias Animales/trasplante , Ratones , Ratones Transgénicos , Receptor ErbB-2/análisis , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Transducción de Señal/efectos de los fármacos , Transgenes/genética
19.
J Clin Oncol ; 17(6): 1876-83, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10561228

RESUMEN

PURPOSE: Liposomal anthracyclines are the present standard treatment for advanced AIDS-related Kaposi's sarcoma (KS). No effective therapies have been defined for use after treatment failure of these agents. A phase II trial was thus conducted with paclitaxel in patients with advanced KS to assess safety and antitumor activity. MATERIALS AND METHODS: A regimen of paclitaxel at a dose of 100 mg/m(2) was given every 2 weeks to patients with advanced AIDS-related KS. Patients were treated until complete remission, disease progression, or unacceptable toxicity occurred. RESULTS: Fifty-six patients with advanced AIDS-related KS were accrued. Tumor-associated edema was present in 70% of patients and visceral involvement in 45%. Forty patients (71%) had received prior systemic therapy; 31 of these were resistant to an anthracycline. The median entry CD4(+) lymphocyte count was 20 cells/mm(3) (range, 0 to 358). A median of 10 cycles (range, 1 to 54+) of paclitaxel was administered. Fifty-nine percent of patients showed complete (n = 1) or partial response (n = 32) to paclitaxel. The median duration of response was 10.4 months (range, 2.8 to 26.7+ months) and the median survival was 15.4 months. The main side effects of therapy were grade 3 or 4 neutropenia in 61% of patients and mild-to-moderate alopecia in 87%. CONCLUSION: Paclitaxel at 100 mg/m(2) given every 2 weeks is active and well tolerated in the treatment of advanced and previously treated AIDS-related KS. The median duration of response is among the longest observed for any regimen or single agent reported for AIDS-related KS. Paclitaxel at this dosage and schedule is a treatment option for patients with advanced AIDS-related KS, including those who have experienced treatment failure of prior systemic therapy.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Antineoplásicos Fitogénicos/uso terapéutico , Paclitaxel/uso terapéutico , Sarcoma de Kaposi/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Adulto , Antineoplásicos Fitogénicos/efectos adversos , Relación Dosis-Respuesta a Droga , Edema/diagnóstico , Edema/tratamiento farmacológico , Femenino , Neoplasias Gastrointestinales/complicaciones , Neoplasias Gastrointestinales/diagnóstico , Neoplasias Gastrointestinales/tratamiento farmacológico , Neoplasias Gastrointestinales/mortalidad , Humanos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Paclitaxel/efectos adversos , Inducción de Remisión , Sarcoma de Kaposi/complicaciones , Sarcoma de Kaposi/diagnóstico , Sarcoma de Kaposi/mortalidad , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/mortalidad , Tasa de Supervivencia , Resultado del Tratamiento
20.
Arch Intern Med ; 145(7): 1231-4, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4015271

RESUMEN

Demonstration of the fistulous tract linking pancreatic pseudocysts to the mediastinum and pleural cavity has diagnostic and therapeutic implications. In four cases, pseudocyst drainage through the esophageal and aortic diaphragmatic crus into the mediastinum and pleural cavity was delineated by computed tomography. In two cases, significant pericardial effusions were demonstrated. Computed tomography offers an effective diagnostic method when treatment is dependent on anatomic localization of the disrupted pseudocyst and its intrathoracic drainage tract.


Asunto(s)
Quiste Pancreático/fisiopatología , Derrame Pleural/fisiopatología , Tomografía Computarizada por Rayos X , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Quiste Pancreático/terapia , Derrame Pericárdico/complicaciones , Derrame Pleural/complicaciones
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