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1.
Med Vet Entomol ; 32(4): 462-472, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30027674

RESUMO

The flea genus Neotyphloceras Rothschild (Siphonaptera: Ctenophthalmidae) includes five species and two subspecies distributed from Venezuela to southern Chile and Argentina. Only Neotyphloceras crassispina hemisus Jordan has been registered in Bolivia. The present study examines species of Neotyphloceras collected in Bolivian localities in the Departments of La Paz, Cochabamba and Tarija, and describes the morphology of the modified abdominal segments in males and females of Neotyphloceras rosenbergi Rothschild on the basis of type material and specimens collected from Tarija. A new species, Neotyphloceras boliviensis n. sp., is described and new host associations are reported for N. rosenbergi, Neotyphloceras crassispina crassispina and N. crassispina hemisus. Neotyphloceras c. crassispina and N. rosenbergi are reported for the first time in Bolivia. The distribution of N. rosenbergi is extended 1600 km to the south. Given the potential medical and veterinary significance of fleas as disease vectors, and considering that in the Departments of La Paz and Tarija several human cases of plague have been reported, and species of flea have been identified as main vectors of these diseases, the new records of fleas in Bolivia reported herein may be useful for epidemiological studies on flea-borne diseases.


Assuntos
Infestações por Pulgas/veterinária , Gambás/parasitologia , Ratos/parasitologia , Doenças dos Roedores/parasitologia , Sigmodontinae/parasitologia , Sifonápteros/classificação , Animais , Bolívia/epidemiologia , Feminino , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/parasitologia , Masculino , Doenças dos Roedores/epidemiologia , Sifonápteros/anatomia & histologia
2.
Lett Appl Microbiol ; 66(6): 491-495, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29575121

RESUMO

The continued emergence and global spread of bacterial antibiotic resistance has fuelled the search for novel antimicrobial agents and resistance-modifying compounds. Manuka honey has both antimicrobial properties and the ability to increase the efficacy of FDA-approved antibiotic drugs. Compared to other types of honey, manuka honey contains elevated levels of methylglyoxal (MGO), a small molecule that contributes to its antibacterial activity. Manuka honey has shown particular promise for the treatment of antibiotic-resistant Gram-positive organisms such as methicillin-resistant Staphylococcus aureus. Linezolid is an oxazolidinone antibiotic used in the treatment of infections caused by a range of Gram-positive pathogens. Here, we demonstrate that manuka honey, as well as MGO in isolation, increases the sensitivity of S. aureus to linezolid in both agar diffusion and broth microdilution assays. This synergistic interaction is mediated in part by increased intracellular accumulation of linezolid in the presence of MGO. SIGNIFICANCE AND IMPACT OF THE STUDY: Manuka honey is widely recognized for its antimicrobial activity. Our study adds to the growing body of evidence that manuka honey and its active ingredient, methylglyoxal (MGO), can also function as antibiotic adjuvants. In this study, we provide the first report of synergy between MGO and linezolid against Staphylococcus aureus. Both manuka honey and purified MGO significantly increased the sensitivity of S. aureus to linezolid.


Assuntos
Antibacterianos/farmacologia , Mel/análise , Linezolida/farmacologia , Aldeído Pirúvico/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Farmacorresistência Bacteriana , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Aldeído Pirúvico/análise , Infecções Estafilocócicas/tratamento farmacológico
3.
J Helminthol ; 91(6): 762-766, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27809941

RESUMO

A unique adaptation of many internal parasites of mammals is their ability to stay in the intestine for extended periods of time and resist the normal peristaltic movements and forces that push and expel material. To better understand parasite adhesion behaviour and replicate their attachment method in medical devices, an experiment was designed and performed using the rat tapeworm, Hymenolepis diminuta. The experiment employed a tensile test machine and a digital scale and was designed to calculate the attachment strength of the scolex to the mucosa through the change of the value of the digital scale during the tensile test. The attachment force of H. diminuta is 0.021 ± 0.011 g. This method could be applied in studies of parasite biomechanics and the results may help medical device researchers to better mimic the unique functional morphology of this species of parasite.


Assuntos
Himenolepíase/veterinária , Hymenolepis diminuta/química , Hymenolepis diminuta/fisiologia , Intestinos/parasitologia , Parasitologia/métodos , Doenças dos Roedores/parasitologia , Animais , Fenômenos Biomecânicos , Himenolepíase/parasitologia , Parasitologia/instrumentação , Ratos
4.
J Helminthol ; 89(1): 34-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26262594

RESUMO

Plagioscion squamosissimus (Heckel, 1840) (Osteichthyes: Sciaenidae) is considered piscivorous and is a generalist species endemic to the Amazon region. This fish is an important part of the natural ecosystems in which it occurs and provides basic functional components in the food web. The genus Neoechinorhynchus Stiles & Hassall, 1905 is distributed worldwide and parasitizes fish and turtles, but there are few reports of parasites of this genus in South America, due to the high diversity of fish that can be found in this region. A new species of thorny-headed worm (Acanthocephala: Neoechinorhynchidae) is described from P. squamosissimus from Guajará Bay, Belém, Pará, Brazil. In general, the unique characteristics of the hooks on the anterior end of the proboscis and the length-to-width ratio relationship separate this new species from other described species in the genus Neoechinorhynchus. Although the species in this genus are mostly found in North America, the dearth of species known from the neotropics may be due to the lack of studies in this region.


Assuntos
Acantocéfalos/isolamento & purificação , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Intestinos/parasitologia , Acantocéfalos/anatomia & histologia , Acantocéfalos/classificação , Acantocéfalos/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Feminino , Masculino , Perciformes/parasitologia
5.
Eur J Cancer Care (Engl) ; 23(4): 481-92, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24472013

RESUMO

Couplelinks is an original, professionally facilitated online intervention tailored to the unique challenges facing young women with breast cancer and their male partners. The purpose of this evaluation was to determine the feasibility and acceptability of the intervention and areas for improvement. Sixteen couples were sequentially enrolled over an 18-month period. Couples provided feedback via a treatment satisfaction survey, and post-treatment interviews with a sub-group of participants. Qualitative information was analysed for themes relevant to the program's acceptability, perceived benefits and limitations, and directions for improvement. Of the 16 couples who enrolled, six completed four modules or less, and 10 completed the entire program. Completers reported satisfaction with the program overall, as well as with the website useability and professional facilitation. Reported benefits were: enhanced communication and self-other knowledge; creation of opportunities for meaningful, cancer-related discussion; affirmation of relationship strengths; and a greater sense of closeness between partners. The main reported limitation was how program participation disrupted the couple's usual routine. Themes related to non-completion suggest that partners with particularly elevated relational or illness-related distress, or with differential levels of motivation, are less likely to finish. These findings have led to targeted improvements to the website and intervention protocol.


Assuntos
Neoplasias da Mama/psicologia , Características da Família , Internet , Estresse Psicológico/terapia , Adulto , Comunicação , Estudos de Viabilidade , Feminino , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Satisfação do Paciente , Projetos Piloto , Estresse Psicológico/psicologia , Terapia Assistida por Computador
6.
J Parasitol ; 106(5): 611-615, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32997755

RESUMO

Oxyuricassis ekstromi n. sp. is the third species of the genus described from the intestine of Lasiancistrus saetiger Armbruster in Brazil. This species can be easily differentiated from its congeners by the presence of a tooth-like sclerotized piece that occupies half of the stoma and absence of spine projections on the tail of both males and females. Also, males of the new species lack caudal alae present in Oxyuricassis coronatus and Oxyuricassis hexaspinatus. Additionally, we observed a different number and pattern of the distribution of cloacal papilla; males of O. coronatus and O. hexaspinatus have 1 pair of pre-cloacal and 2 pairs of post-cloacal papillae; while the new species has 1 pre-cloacal and 3 post-cloacal pairs of papillae.


Assuntos
Peixes-Gato/parasitologia , Doenças dos Peixes/parasitologia , Enteropatias Parasitárias/veterinária , Oxiuríase/veterinária , Oxyuroidea/classificação , Animais , Brasil , Feminino , Enteropatias Parasitárias/parasitologia , Intestinos/parasitologia , Masculino , Microscopia Eletrônica de Varredura/veterinária , Oxiuríase/parasitologia , Oxyuroidea/anatomia & histologia , Oxyuroidea/ultraestrutura , Rios
7.
Bone Marrow Transplant ; 41(10): 867-72, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18246113

RESUMO

The aim of this study was to identify risk factors associated with PFS in patients with Ewing sarcoma undergoing ASCT; 116 patients underwent ASCT in 1989-2000 and reported to the Center for International Blood and Marrow Transplant Research. Eighty patients (69%) received ASCT as first-line therapy and 36 (31%), for recurrent disease. Risk factors affecting ASCT were analyzed with use of the Cox regression method. Metastatic disease at diagnosis, recurrence prior to ASCT and performance score <90 were associated with higher rates of disease recurrence/progression. Five-year probabilities of PFS in patients with localized and metastatic disease at diagnosis who received ASCT as first-line therapy were 49% (95% CI 30-69) and 34% (95% CI 22-47) respectively. The 5-year probability of PFS in patients with localized disease at diagnosis, and received ASCT after recurrence was 14% (95% CI 3-30). PFS rates after ASCT are comparable to published rates in patients with similar disease characteristics treated with conventional chemotherapy, surgery and irradiation suggesting a limited role for ASCT in these patients. Therefore, ASCT if considered should be for high-risk patients in the setting of carefully controlled clinical trials.


Assuntos
Agonistas Mieloablativos/uso terapêutico , Sarcoma de Ewing/terapia , Transplante de Células-Tronco/métodos , Adolescente , Adulto , Criança , Terapia Combinada , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sarcoma de Ewing/mortalidade , Sarcoma de Ewing/secundário , Análise de Sobrevida , Transplante Autólogo
8.
J Parasitol ; 103(2): 176-182, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27902893

RESUMO

This study presents the helminth composition and parameters of infection by several species of nematodes in teiid lizards, Ameiva ameiva ameiva (Linnaeus, 1758), Cnemidophorus cryptus Cole and Dessauer, 1993, and Kentropyx calcarata Spix, 1825 from the Brazilian Amazonian Rainforest. The population of lizards studied were parasitized by 6 species of Phylum Nemata including: Spinicauda spinicauda (Olfers, 1919), Parapharyngodon alvarengai Freitas, 1957, Physaloptera sp. (adults), Physaloptera sp. (larvae), Piratuba digiticauda Lent and Freitas, 1941, and Anisakidae (larvae). The overall prevalence was 66.17% and the mean intensity of infection was 19.40 ± 25.48. The association between the body-length of lizards and the abundance and richness of parasitic nematodes was statistically significant only in Ameiva a. ameiva. A new host record is reported here with 1 specimen of the family Anasakidae in Ameiva a. ameiva. Both S. spinicauda and Physaloptera sp. represent new records from C. cryptus.


Assuntos
Ascaridoidea/classificação , Lagartos/parasitologia , Infecções por Nematoides/veterinária , Oxyuroidea/classificação , Spiruroidea/classificação , Animais , Brasil/epidemiologia , Feminino , Lagartos/anatomia & histologia , Masculino , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Prevalência , Floresta Úmida
9.
Bone Marrow Transplant ; 51(7): 945-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26950375

RESUMO

Since 1991, three sequential prospective clinical trials have been conducted by the 'Head Start' (HS) Consortium in which young children with newly-diagnosed malignant central nervous system (CNS) tumors were treated with induction chemotherapy followed by single-cycle marrow-ablative chemotherapy and autologous hematopoietic rescue as a means of improving disease cure rate and quality of survival through avoidance (<6 years old at diagnosis) or reduction (6-10 years old) of brain irradiation. Bone Marrow (HS I) or filgrastim-mobilized peripheral hematopoietic cells (HS II and III) were obtained following recovery from the first and/or second induction cycles. Radiotherapy was administered following all chemotherapy only for patients with residual tumor following completion of induction or with age greater than 6 years at diagnosis. Two hundred and twenty-six children were enrolled on three consecutive HS trials with primary malignant CNS tumors and underwent marrow-ablative chemotherapy. The 100-day treatment-related mortality (TRM) steadily declined as did grade IV transplant-related oropharyngeal mucositis. Factors most likely associated with the decrease in TRM and morbidity are increasing experience with the marrow-ablative chemotherapy regimen combined with improved leukapheresis and post-reinfusion supportive care techniques, contributing toward improved overall survival.


Assuntos
Neoplasias do Sistema Nervoso Central/terapia , Ensaios Clínicos como Assunto/normas , Transplante de Células-Tronco Hematopoéticas/métodos , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/radioterapia , Criança , Terapia Combinada , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Transplante de Células-Tronco Hematopoéticas/tendências , Humanos , Quimioterapia de Indução/métodos , Morbidade/tendências , Mortalidade/tendências , Agonistas Mieloablativos/uso terapêutico , Estudos Retrospectivos , Transplante Autólogo
10.
Bone Marrow Transplant ; 51(4): 542-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26726947

RESUMO

Recurrence of malignant brain tumors results in a poor prognosis with limited treatment options. High-dose chemotherapy with autologous hematopoietic cell rescue (AHCR) has been used in patients with recurrent malignant brain tumors and has shown improved outcomes compared with standard chemotherapy. Temozolomide is standard therapy for glioblastoma and has also shown activity in patients with medulloblastoma/primitive neuro-ectodermal tumor (PNET), particularly those with recurrent disease. Temozolomide was administered twice daily on days -10 to -6, followed by thiotepa 300 mg/m(2) per day and carboplatin dosed using the Calvert formula or body surface area on days -5 to -3, with AHCR day 0. Twenty-seven patients aged 3-46 years were enrolled. Diagnoses included high-grade glioma (n=12); medulloblastoma/PNET (n=9); central nervous system (CNS) germ cell tumor (n=4); ependymoma (n=1) and spinal cord PNET (n=1). Temozolomide doses ranged from 100 mg/m(2) per day to 400 mg/m(2) per day. There were no toxic deaths. Prolonged survival was noted in several patients including those with recurrent high-grade glioma, medulloblastoma and CNS germ cell tumor. Increased doses of temozolomide are feasible with AHCR. A phase II study using temozolomide, carboplatin and thiotepa with AHCR for children with recurrent malignant brain tumors is being conducted through the Pediatric Blood and Marrow Transplant Consortium.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Autoenxertos , Carboplatina/administração & dosagem , Criança , Pré-Escolar , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Taxa de Sobrevida , Temozolomida , Tiotepa/administração & dosagem
11.
J Clin Oncol ; 16(1): 222-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9440746

RESUMO

PURPOSE: Medulloblastoma is a highly lethal disease when it recurs. Very few patients survive with conventional treatment. This study evaluated the use of high-dose carboplatin, thiotepa, and etoposide with autologous stem-cell rescue (ASCR) in patients with recurrent medulloblastoma. METHODS: Chemotherapy consisted of carboplatin 500 mg/m2 (or area under the curve = 7 mg/mL x min via Calvert formula) on days -8, -7, and -6; and thiotepa 300 mg/m2 and etoposide 250 mg/m2 on days -5, -4, and -3; followed by ASCR on day 0. In addition to the study-prescribed therapy, 21 patients received other treatment: neurosurgical resection in seven, conventional chemotherapy in 17, and external-beam irradiation in 11 cases. RESULTS: Twenty-three patients with recurrent medulloblastoma, aged two to 44 years (median, 13 years) at ASCR, were treated. Three patients died of treatment-related toxicities within 21 days of ASCR; multiorgan system failure in two, and Aspergillus infection with venoocclusive disease in one. Seven of 23 patients (30%) are event-free survivors at a median of 54 months post-ASCR (range, 24 to 78 months). Kaplan-Meier estimates of event-free (EFS) and overall survival are 34% +/- 10% and 46% +/- 11%, respectively, at 36 months post-ASCR. CONCLUSION: This strategy may provide long-term survival for some patients with recurrent medulloblastoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Cerebelares/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas , Meduloblastoma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Neoplasias Cerebelares/mortalidade , Criança , Pré-Escolar , Terapia Combinada , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Lactente , Masculino , Meduloblastoma/mortalidade , Recidiva Local de Neoplasia/mortalidade , Análise de Sobrevida , Tiotepa/administração & dosagem , Tiotepa/efeitos adversos , Transplante Autólogo
12.
Int J Parasitol ; 25(9): 1065-75, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8847168

RESUMO

Classical and morphometric analyses were conducted on several samples of oxyurid nematodes parasitic in strepsirrhine primates: Cheirogaleus major, Galago senegalensis, and Microcebus murinus. A diagnosis of Lemuricola contagiosus Chabaud & Petter, 1959 from C. major is given using syntypes, from which a lectotype is selected. The rest of the specimens were compared to L. contagiosus. From measurements taken from each sex, an initial Principal Component Analysis (PCA) was performed on log-transformed data and a second PCA was performed on log-shape ratios after elimination of the isometric differences. The parasites collected from M. murinus, which can be differentiated from the closely related L. contagiosus by both standard morphological characters and morphometric variables, are described as Lemuricola microcebi n. sp. The parasites collected from Galago are morphologically very similar to L. microcebi n. sp. The most probable explanation for this resemblance is considered to be a transfer from Microcebus to Galago but, due to the small numbers of individuals in our samples, it is impossible to eliminate the possibility that the parasites of Galago belong to an undescribed species. Until more material or information can be obtained, it is proposed to refer to the parasites from Galago as Lemuricola sp.


Assuntos
Oxyuroidea/anatomia & histologia , Oxyuroidea/fisiologia , Primatas/parasitologia , Animais , Cheirogaleidae/parasitologia , Feminino , Galago/parasitologia , Lemur/parasitologia , Masculino , Especificidade da Espécie
13.
Int J Parasitol ; 26(2): 147-59, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8690538

RESUMO

Recent redescriptions of most members of the Oxyuridae Cobbold, 1864 parasitic in primates revealed that they share following derived characters: sexual dimorphism of lateral alae (single-crested in the males, double-crested in the females); in males a second pair of genital papillae always surrounded by strongly cuticularized rings; in females, uterine tube divided into 2 parts by a cellular wall forming a diaphragm. These characters are interpreted as synapomorphies, providing evidence that these taxa represent a monophyletic group, and we propose to classify them in a new subfamily of the Oxyuridae: the Enterobiinae subfam.nov. The Enterobiinae as recognized herein occurs in both Old World and New World Primates and rodents of the family Sciuridae (tribe Sciurini in the Holarctic region and tribe Xerini in the Ethiopian region). The new subfamily includes the following genera: Enterobius Leach, 1853; Colobenterobius Quentin, Betterton & Krishnasamy, 1979; Rodentoxyuris Quentin & Tenora 1974; Xeroxyuris Hugot, 1995; Lemuricola Chabaud & Petter, 1959; Protenterobius Inglis, 1961; Madoxyuris Chabaud, Brygoo & Petter, 1965; Trypanoxyuris Vevers, 1923; Hapaloxyuris Inglis & Cosgrove, 1965 and Paraoxyuronema Artigas, 1936. The genus Paraoxyuronema is revalidated as a subgenus of Trypanoxyuris due to its specialized buccal structures. This genus groups all pinworm nematodes specific for primates of the family Atelidae, including: P. brachytelesi Artigas, 1937 occurring in Brachyteles arachnoides; P. atelis (Cameron, 1929) occurring in Ateles spp., and P. duplicidens (Buckley, 1931) and P. lagothricis (Buckley, 1931), which are parasites of Lagothrix spp. Inglisoxyuris inglisi Chabaud, Petter & Golvan, 1961, included in the monospecific genus Inglisoxyuris and previously classified as a subgenus of the Lemuricola, does not share the characters of the new subfamily and, until its precise classification can be considered with more information, it is proposed to refer to this species as an Oxyuridae sensu lato. A diagnosis and a key of the genera included in the new subfamily are given.


Assuntos
Oxyurida/classificação , Oxyurida/patogenicidade , Primatas/parasitologia , Sciuridae/parasitologia , Animais , Enterobius/anatomia & histologia , Enterobius/classificação , Enterobius/patogenicidade , Feminino , Masculino , Oxyurida/anatomia & histologia , Infecções por Oxyurida/diagnóstico , Infecções por Oxyurida/veterinária , Caracteres Sexuais
14.
Int J Parasitol ; 29(2): 275-84, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10221628

RESUMO

Faecal samples collected from 300 Bolivian marsupials (Didelphimorphia: Didelphidae) between 1984 and 1993 were examined for coccidian parasites. Sporulated oocysts were present in the faeces of 50 (17%) marsupials representing 11 genera and 22 species. Three new species of Eimeria are described and named from six host species. One species occurred in Marmosops dorothea, Monodelphis domestica and Thylamys venustus, another in Micoureus constantiae constantiae and Micoureus constantiae budini and a third in Marmosops dorothea. A discriminant analysis performed on five quantitative oocyst measurements revealed similarities between the first and third Eimeria species because of similar sizes and shapes of the oocysts, whereas the second Eimeria species was structurally discrete. The Eimeria that infects multiple hosts may be a common widespread species. Future surveys are advised for a thorough assessment of the coccidian biodiversity within Bolivian marsupials.


Assuntos
Coccidiose/veterinária , Eimeria/classificação , Eimeria/isolamento & purificação , Gambás/parasitologia , Animais , Bolívia/epidemiologia , Coccidiose/epidemiologia , Coccidiose/parasitologia , Eimeria/crescimento & desenvolvimento , Fezes/parasitologia , Gambás/classificação
15.
Cancer Chemother Pharmacol ; 34(4): 331-4, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8033300

RESUMO

To test the feasibility of a regimen of high-dose cisplatin, ifosfamide, and etoposide (VP-16; VIPP regimen), we registered 15 patients with advanced non-small-cell lung cancer in a phase I trial of the Northern California Oncology Group. One cycle of treatment consisted of high-dose cisplatin given at 100 mg/m2 i.v. on days 1 and 8, VP-16 given at 60-75 mg/m2 i.v. on days 1-3, plus ifosfamide given at 1.0-1.2 g/m2 i.v. on days 1-3; cycles were repeated every 28 days. There were 13 men and 2 women; the median age was 59 years (range, 47-72 years). The median Karnofsky performance status (KPS) was 90 (range, 70-100). All patients were assessable for toxicity and response. The median number of cycles delivered per patient was two (range, one to four). Hematologic toxicity was dose-limiting and required de-escalation of the ifosfamide and VP-16 doses. Ten patients developed a white blood count of < 1000/mm3 and seven patients developed a platelet count of < 50,000/mm3. The duration of cytopenia increased progressively with each subsequent cycle of therapy. Two patients required antibiotics for neutropenic fever with documented infections (pneumonia, bacteremia). Seven patients received red blood cell transfusions for a hemoglobin level of < 8 gm/dl. Grade III or IV non-hematologic toxicities were uncommon and involved one patient each with grade 3 ototoxicity and grade 3 neurotoxicity. Five patients developed laboratory evidence of renal salt wasting. The overall response rate was 33% (5/15) with a complete response being achieved by two patients (13%) and a partial response being attained by three (20%). The overall median survival was 44 weeks. We conclude that although this regimen demonstrated activity, hematologic toxicity limited its use in the palliative treatment of non-small-cell lung cancer. Using hemopoietic growth-factor support to permit dose escalation, this schedule of VIPP may be of interest in a number of different chemotherapy-sensitive tumor types.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Esquema de Medicação , Etoposídeo/administração & dosagem , Estudos de Viabilidade , Feminino , Humanos , Ifosfamida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
16.
Free Radic Res ; 31 Suppl: S137-45, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10694052

RESUMO

The origin of the oxidative burst during plant-pathogen interactions remains controversial. A number of possibilities have been identified, which involve the protoplast, plasmalemma or apoplast. The apoplastic production of H2O2 requires three components, an extracellular peroxidase, ion fluxes leading to extracellular alkalinisation and release of a substrate. Fatty acids are the major compounds that appear in the apoplast following elicitation, which can activate H2O2 production by peroxidases in vitro. However, the reaction with peroxidases appears to be novel and is uncharacterised at present. The apoplastic mechanism also cannot be readily distinguished from the operation of a plasma membrane NADPH oxidase system by the use of the inhibitors diphenylene iodonium and N,N diethyl-dithiocarbamate since it is also inhibited by these. These inhibitors have often in the past been used to define the involvement of the latter in the oxidative burst. In common with the NADPH oxidase system, the peroxidase responsible has been cloned but unlike the NADPH oxidase it has been shown to function in vitro to generate H2O2. In vivo studies of the oxidative burst have shown that the alkalinisation is essential and the underlying ion fluxes may be regulated by cAMP. Calcium fluxes are also essential. Although the oxidative activity of peroxidase requires calcium the fluxes have obvious other function. These may include activation of release of substrate and through the activation of a CDPK, regulation of enzymes involved in phytoalexin and cell wall phenolic production such as PAL.


Assuntos
Plantas/metabolismo , Explosão Respiratória , Cálcio/metabolismo , Parede Celular/metabolismo , Concentração de Íons de Hidrogênio , Modelos Biológicos , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Peroxidases/metabolismo , Transdução de Sinais , Especificidade por Substrato
17.
J Parasitol ; 77(1): 52-7, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1899451

RESUMO

Fresh (36 days old) sporulated oocysts of Eimeria nieschulzi were divided into 7 groups. Control oocysts were maintained at 23 C in 2% aqueous (w/v) K2Cr2O7. The 6 experimental groups were mixed with either Bouin's solution, 10% aqueous (v/v) buffered formalin, Karnovsky's solution, glutaraldehyde, paraformaldehyde, or 70% aqueous (v/v) ethanol (EtOH). After 115 days, oocysts from all 7 groups were examined under oil immersion to determine the effect of fixation on their structural integrity. The parameters examined were lengths and widths of oocysts and sporocysts, percent sporulation (%S), and percent crenation (%C) of oocysts and sporocysts. The highest destruction (%S and %C) occurred in oocysts exposed to glutaraldehyde and Karnovsky's fixatives where 100% of both oocysts and sporocysts crenated and only 8% and 48%, respectively, remained sporulated. Of the oocysts in paraformaldehyde, 93% remained sporulated, but 95%of these oocysts and 100% of the sporocyst crenated. In Bouin's solution, 75% of the oocysts were intact structurally, but of these, only 60% were still sporulated with 70% of their sporocysts crenated. Oocysts preserved in 70% EtOH were 80% intact and 70% remained sporulated, but nearly 60% of their sporocysts collapsed even though the oocyst walls were intact. Oocysts preserved in 10% buffered formalin maintained structural integrity but had lower numbers of sporulated oocysts (84%) and greater numbers of crenated oocysts (18%) than control oocysts maintained in the dichromate solution (95% and 0%, respectively).


Assuntos
Ácido Acético , Eimeria/efeitos dos fármacos , Fixadores/farmacologia , Preservação Biológica , Acetatos/farmacologia , Animais , Eimeria/anatomia & histologia , Etanol/farmacologia , Formaldeído/farmacologia , Glutaral/farmacologia , Picratos/farmacologia , Polímeros/farmacologia
18.
J Parasitol ; 78(5): 795-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1403419

RESUMO

A new species of cestode of the genus Linstowia (Cestoda: Anoplocephalidae) is described from marsupials of the genera Thylamys and Monodelphis. The new species (Linstowia schmidti) differs from Linstowia iheringi Zschokke, 1904, in having a much smaller strobila and reduced number of proglottids, and in the distribution of the eggs in gravid proglottids. In Bolivia, cestodes of the genus Linstowia appear to have a restricted geographic distribution, occurring in marsupials only in southeastern Bolivia near the western margin of the Chaco. This host-parasite association may represent an ecological-historical relict.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Gambás/parasitologia , Animais , Bolívia/epidemiologia , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia
19.
J Parasitol ; 78(4): 596-600, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1635018

RESUMO

Cestodes of the genus Linstowia, parasitic in marsupials, show patterns of coevolution and ancient historical-ecological connections. Correlated with the breakup of the austral landmasses (Gondwanaland) of the Neotropical and Australian regions from the Antarctic continent, the age of this host-parasite community is estimated to be between 60 and 70 million years old. Based on the data from the survey of parasites of mammals from throughout Bolivia and from the phylogenetic analysis of the cestodes, we urge the planners of biodiversity preserves in the neotropics to consider the Yungas of Bolivia as a region that supports an ancient ecological community worthy of consideration as a biopreserve.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Variação Genética , Gambás/parasitologia , Filogenia , Animais , Austrália , Evolução Biológica , Bolívia , Cestoides/genética , Infecções por Cestoides/parasitologia , Interações Hospedeiro-Parasita , Gambás/genética , Software
20.
J Parasitol ; 86(3): 545-54, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10864253

RESUMO

Filarioid nematodes of the genus Litomosoides occur in the abdominal and (or) thoracic cavities of marsupials, rodents, and bats of the Nearctic and Neotropical regions. In this study, the phylogenetic relationships among these nematodes were estimated with a parsimony analysis of morphological characters derived from species descriptions. This nonweighted analysis produced 20 shortest trees. The monophyly of the genus was not supported in that Litomosoides thomomydis and Litomosoides westi failed to group with the other members of the genus. When these 2 taxa (parasites of pocket gophers) were excluded, monophyly of Litomosoides was supported by 2 synapomorphies (structure of the walls and general shape of the stoma); however, ancestor-descendant relationships among the species in the genus were not well resolved. A posteriori reweighting of the characters produced a single tree, different from all 20 most parsimonious trees. Alternative host-parasite evolutionary models were tested against these results supporting the process of host switching as being most important in forming the patterns of mammal-nematode associations that have been detected in this group of nematodes.


Assuntos
Quirópteros/parasitologia , Filariose/veterinária , Filarioidea/classificação , Marsupiais/parasitologia , Filogenia , Roedores/parasitologia , América , Animais , Feminino , Filariose/parasitologia , Filarioidea/anatomia & histologia , Filarioidea/fisiologia , Interações Hospedeiro-Parasita , Masculino
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