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1.
Pediatr Surg Int ; 37(8): 1061-1068, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33740107

RESUMO

PURPOSE: The neonatal period is the most vulnerable period for a child. There is a paucity of data on the burden of neonatal surgical disease in our setting. The aim of this study was to describe the frequency with which index neonatal surgical conditions are seen within our setting and to document the 30-day outcome of these patients. METHODS: This was a single-centre prospective observational study in which all neonates with paediatric surgical pathology referred to the paediatric surgical unit with a corrected gestational age of 28 days were included. RESULTS: Necrotising enterocolitis was the most frequent reason for referral to the paediatric surgical unit (n = 68, 34.34%). Gastroschisis was the most frequent congenital anomaly referred (n = 20, 10.10%). The overall morbidity was 57.58%. Surgical complications contributed to 18.51% of morbidities. The development of gram negative nosocomial sepsis was the most frequent cause of morbidity (n = 98, 50.78%). Mortality at 30 days was 21.74% (n = 40). Sepsis contributed to mortality in 35 patients (87.5%), 16 of which had gram negative sepsis. CONCLUSION: Gram-negative sepsis was a major contributing factor in the development of morbidity and mortality in our cohort. Prevention and improvement in infection control are imperative if we are to improve outcomes in our surgical neonates.


Assuntos
Enterocolite Necrosante/mortalidade , Gastrosquise/mortalidade , Sepse Neonatal/mortalidade , Complicações Pós-Operatórias/mortalidade , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Estudos Prospectivos , África do Sul/epidemiologia , Centros de Atenção Terciária/estatística & dados numéricos
2.
Ir Med J ; 113(7): 119, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35574822

RESUMO

Aims Our aim was to assess if outcomes for cystic fibrosis (CF) patients at six & sixteen years of age have improved in the last 17 years looking at FEV1, BMI and death. Methods A retrospective observational study using a prospectively maintained database of CF patients at Cork University Hospital. Results 84 patients were included in the 16-year-old data and 89 patients were included in the six-year-old data. The mean FEV1 and BMI (16 years) for the 2002-2007 group was 72.9±21.0% and 18.9±2.53 respectively, 2008-2013 group was 75.4±27.2% and 19.8±2.7 and for the 2014-2018 group was 95.2±16.0% and 22.9±4.1. The percentage of patients (16 years) with chronic pseudomonas status was 37.9% (11/30) in the 2002-2007 group, 51.6 % (16/31) in the 2008-2013 group and 4.2% (1/24) in the 2014-2018 group. The relationship between FEV1 and FVC with BMI remained significant in multivariate analysis (P <0.001). The mean FEV1 (six years) for the 2002-2007 group was 90.7±16.1%, 2008-2013 group was 99.3±17.9% and for the 2014-2018 group was 100.9±15.8%. Conclusions Improvements in FEV1 and BMI aged six and 16 years are notable as well as a significant decline in the number of patients with chronic pseudomonas.

3.
Clin Genet ; 88(4): 386-90, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25256757

RESUMO

A novel X-linked intellectual disability (XLID) syndrome with moderate intellectual disability and distinguishing craniofacial dysmorphisms had been previously mapped to the Xq26-q27 interval. On whole exome sequencing in the large family originally reported with this disorder, we identified a 23 bp frameshift deletion in the RNA binding motif protein X-linked (RBMX) gene at Xq26 in the affected males (n = 7), one carrier female, absent in unaffected males (n = 2) and in control databases (7800 exomes). The RBMX gene has not been previously causal of human disease. We examined the genic intolerance scores for the coding regions and the non-coding regions of RBMX; the findings were indicative of RBMX being relatively intolerant to loss of function variants, a distinctive pattern seen in a subset of XLID genes. Prior expression and animal modeling studies indicate that loss of function of RBMX results in abnormal brain development. Our finding putatively adds a novel gene to the loci associated with XLID and may enable the identification of other individuals affected with this distinctive syndrome.


Assuntos
Exoma , Ribonucleoproteínas Nucleares Heterogêneas/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Adolescente , Adulto , Idoso , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem
4.
Intern Med J ; 45(10): 1037-43, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26178306

RESUMO

BACKGROUND: Carbapenems are traditionally reserved as the last line of defence for treatment of serious infections with multiresistant Gram-negative bacilli. Reports of Klebsiella pneumoniae carbapenemase (KPC)-producing organisms have been emerging globally, but rare in Australasia to date. We describe an outbreak of KPC-2 producing K. pneumoniae at an Australian hospital. METHODS: After initial detection in October 2012, a retrospective review of patients with meropenem-resistant K. pneumoniae to June 2012, and ongoing prospective surveillance, was undertaken. Included patients were admitted to the hospital after June 2012 and had meropenem-resistant K. pneumoniae isolated from any site. Available isolates underwent detection of the KPC-2 gene by polymerase chain reaction and molecular typing was performed to determine genetic relatedness between isolates. Point-prevalence screening was performed on selected wards to detect asymptomatic carriage. Infection control procedures were implemented to contain the outbreak. RESULTS: Ten cases were identified in the initial cluster. Eight were localised to a single inpatient ward. Point-prevalence screening revealed one extra case. After temporary containment, re-emergence of KPC-producing isolates was observed post October 2013 with 18 further cases identified. Four K. pneumoniae isolates in the 2012 cluster and 16 from the 2013-2014 cluster were referred for further testing. All carried the KPC-2 beta-lactamase gene. The 2012 isolates were genetically similar to the 2014 isolates. CONCLUSION: KPC-2 mediated resistance is an emerging threat in Australia. The re-emergence of KPC despite initial containment emphasises the need for constant vigilance in the microbiology laboratory and ongoing maintenance of infection control and antimicrobial stewardship activity.


Assuntos
Infecção Hospitalar/tratamento farmacológico , Mortalidade Hospitalar , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/isolamento & purificação , Resistência beta-Lactâmica/genética , beta-Lactamases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Austrália/epidemiologia , Carbapenêmicos/uso terapêutico , Surtos de Doenças , Feminino , Humanos , Controle de Infecções , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Ir Med J ; 108(8): 250-1, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26485836

RESUMO

We report the case of an asymptomatic arteriovenous malformation (AVM), extending from the forearm into the palm, in an 11-year-old boy. A debulking procedure was performed meticulously dissecting the lesion from the involved structures. The post-operative course was uncomplicated and no evidence of recurrence was noted at eighteen months follow-up. Extensive AVMs involving structures vital for hand function may be asymptomatic. Clinical follow-up is paramount, due to the inherent risk of recurrence.


Assuntos
Malformações Arteriovenosas/diagnóstico , Antebraço/irrigação sanguínea , Deformidades Congênitas da Mão/diagnóstico , Mãos/irrigação sanguínea , Criança , Antebraço/anormalidades , Antebraço/cirurgia , Mãos/cirurgia , Humanos , Masculino
6.
Ir Med J ; 107(6): 180-1, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24988837

RESUMO

Nasopharyngeal cancer is unique among head and neck cancers. Despite definitive treatment, there is a high rate of recurrence, most commonly in the bone, lung or liver. Brain metastases and particularly, leptomeningeal carcinomatosis are extremely rare. We present a case of recurrent nasopharyngeal carcinoma with brain metastases and leptomeningeal carcinomatosis in the absence of local recurrence and systemic metastases.


Assuntos
Neoplasias Encefálicas/secundário , Carcinoma/secundário , Neoplasias Nasofaríngeas/patologia , Neoplasias da Medula Espinal/secundário , Adulto , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/terapia , Carcinoma/terapia , Quimiorradioterapia , Humanos , Neoplasias Nasofaríngeas/terapia , Neoplasias da Medula Espinal/terapia
7.
Microbiol Spectr ; 12(1): e0297923, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38047694

RESUMO

IMPORTANCE: We present a protocol to efficiently sequence genomes of the MPXV-causing mpox. This enables researchers and public health agencies to acquire high-quality genomic data using a rapid and cost-effective approach. Genomic data can be used to conduct surveillance and investigate mpox outbreaks. We present 91 mpox genomes that show the diversity of the 2022 mpox outbreak in Ontario, Canada.


Assuntos
Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Sequenciamento Completo do Genoma , Genômica , Surtos de Doenças , Ontário/epidemiologia
8.
J Exp Med ; 172(4): 1217-24, 1990 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-2212951

RESUMO

To study the effects of localized secretion of cytokines on tumor progression, the gene for human interleukin 2 (IL-2) was introduced via retroviral vectors into CMS-5 cells, a weakly immunogenic mouse fibrosarcoma cell line of BALB/c origin. Secretion of low levels of IL-2 from the tumor cells abrogated their tumorigenicity and induced a long-lasting protective immune response against a challenge with a tumorigenic dose of parental CMS-5 cells. Co-injection of IL-2-producing CMS-5 cells with unmodified tumor cells inhibited tumor formation even when highly tumorigenic doses of CMS-5 cells were used. Cytolytic activity in mice injected with parental CMS-5 cells was transient and was greatly diminished 3 wk after injection, as commonly observed in tumor-bearing animals. However, in mice injected with IL-2-producing cells, tumor-specific cytolytic activity persisted at high levels for the duration of the observation period (at least 75 d). High levels of tumor-specific cytolytic activity could also be detected in parental CMS-5 tumor-bearing animals 18 d after inoculation with tumor cells, if IL-2-producing CMS-5 cells but not unmodified parental tumor cells were used as targets. These studies highlight the potential advantages of localized secretion of cytokines mediated via gene transfer to induce potent anti-tumor immune responses.


Assuntos
Interleucina-2/genética , Neoplasias Experimentais/imunologia , Transfecção , Animais , Citotoxicidade Imunológica , Humanos , Interleucina-2/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas
9.
J Small Anim Pract ; 60(7): 430-437, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30790291

RESUMO

OBJECTIVES: To compare the progression-free survival of dogs with high-grade T-cell lymphoma treated with either a cyclophosphamide, doxorubicin, vincristine and prednisone-based or a modified mechlorethamine, vincristine, prednisone and procarbazine chemotherapy protocol. MATERIALS AND METHODS: In this retrospective study, cases were selected based on histologic or cytologic diagnosis of lymphoma, T-cell phenotype, hypercalcaemia, or both, and no previous chemotherapy for lymphoma. Treatment was not randomly allocated. RESULTS: Seventy-three dogs were included in this study: 50 in the cyclophosphamide, doxorubicin, vincristine and prednisone group and 23 in the mechlorethamine, vincristine, prednisone and procarbazine group. The median progression-free survival was 133 days for dogs in the cyclophosphamide, doxorubicin, vincristine and prednisone group and 97 days for dogs in the mechlorethamine, vincristine, prednisone and procarbazine group. When golden retrievers (n = 16) were evaluated -separately, progression-free survival was longer in the cyclophosphamide, doxorubicin, vincristine and prednisone versus mechlorethamine, vincristine, prednisone and procarbazine treatment group (median PFS 154 days versus 70.5 days, respectively). CLINICAL SIGNIFICANCE: The progression-free survival time for dogs with multi-centric T-cell lymphoma treated with a modified mechlorethamine, vincristine, prednisone and procarbazine protocol was similar to that of dogs treated with cyclophosphamide, doxorubicin, vincristine and prednisone. Further studies, including those evaluating golden retrievers separately, are needed to confirm these findings.


Assuntos
Hipercalcemia/veterinária , Linfoma/tratamento farmacológico , Linfoma/veterinária , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Asparaginase/uso terapêutico , Ciclofosfamida/uso terapêutico , Doenças do Cão , Cães , Doxorrubicina/uso terapêutico , Prednisona/uso terapêutico , Estudos Retrospectivos , Linfócitos T , Vincristina/uso terapêutico
10.
J Small Anim Pract ; 60(1): 32-37, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30209807

RESUMO

OBJECTIVES: To determine whether the addition of metronomic chemotherapy improved outcome for dogs with splenic haemangiosarcoma treated with splenectomy and adjuvant maximum tolerated dose chemotherapy. MATERIALS AND METHODS: Medical records were examined retrospectively for dogs with splenic haemangiosarcoma that had undergone splenectomy followed by anthracycline-based chemotherapy. Thirty-nine dogs underwent splenectomy followed by maximum tolerated dose chemotherapy with an anthracycline, cyclophosphamide, or both (Group 1). Twenty-two dogs underwent splenectomy followed by adjuvant maximum tolerated dose chemotherapy with an anthracycline, cyclophosphamide, or both, plus metronomic chemotherapy (Group 2). Dogs in both groups were further separated into those treated with either maximum tolerated dose anthracycline or maximum tolerated dose anthracycline and cyclophosphamide. RESULTS: Median progression-free survival was 165 days and median overall survival time was 180 days in Group 1. Median progression-free survival was 185 days and median overall survival time was 212 days in Group 2. In both groups, the overall survival was shorter in dogs that had received maximum tolerated dose cyclophosphamide. CLINICAL SIGNIFICANCE: The addition of metronomic to maximum tolerated dose chemotherapy protocols does not appear to improve outcome in dogs with splenic haemangiosarcoma treated with splenectomy and maximum tolerated dose chemotherapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Doenças do Cão/tratamento farmacológico , Hemangiossarcoma/veterinária , Administração Metronômica/veterinária , Animais , Antraciclinas/administração & dosagem , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Doenças do Cão/cirurgia , Cães , Feminino , Hemangiossarcoma/tratamento farmacológico , Hemangiossarcoma/cirurgia , Estimativa de Kaplan-Meier , Masculino , Dose Máxima Tolerável , Estudos Retrospectivos , Baço/patologia , Baço/cirurgia , Resultado do Tratamento
12.
J Clin Microbiol ; 46(6): 2074-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18400916

RESUMO

The ResPlex I assay (Qiagen) was designed to amplify and detect DNA of six bacterial respiratory pathogens. This assay was compared with real-time PCR assays based upon the same target sequences for the ability detect the target bacteria by use of both stock strains and specimens from respiratory disease patients. The ResPlex I assay is somewhat less sensitive than real-time PCR assays but offers the advantage of multiple assays in a single reaction.


Assuntos
Bactérias/classificação , Reação em Cadeia da Polimerase/métodos , Kit de Reagentes para Diagnóstico , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/microbiologia , Bactérias/genética , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Primers do DNA , DNA Bacteriano/análise , Humanos , Sistema Respiratório/microbiologia , Sensibilidade e Especificidade
13.
Can Commun Dis Rep ; 44(10): 231-236, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31524884

RESUMO

BACKGROUND: Lyme disease is an infection caused by the spirochete Borrelia burgdorferi and, in most of North America, is transmitted by the blacklegged tick Ixodes scapularis. Climate change has contributed to the expansion of the geographic range of blacklegged ticks in Ontario, increasing the risk of Lyme disease for Ontarians. OBJECTIVE: To identify the number of cases and incidence rates, as well as the geographic, seasonal and demographic distribution of Lyme disease cases reported in Ontario in 2017, with comparisons to historical trends. METHODS: Data for confirmed and probable Lyme disease cases with episode dates from January 1, 2012, through December 31, 2017, were extracted from the integrated Public Health Information System (iPHIS). Data included public health unit (PHU) of residence, episode date, age and sex. Population data from Statistics Canada were used to calculate provincial and PHU-specific incidence rates per 100,000 population. The number of cases reported in 2017 by PHU of residence, month of occurrence, age and sex was compared to the 5-year averages for the period 2012-2016. RESULTS: There were 959 probable and confirmed cases of Lyme disease reported in Ontario in 2017. This was three times higher than the 5-year (2012-2016) average of 313. The provincial incidence rate for 2017 was 6.7 cases per 100,000 population, although this varied markedly by PHU. The highest incidence rates were found in Leeds-Grenville and Lanark District (128.8 cases per 100,000), Kingston-Frontenac, Lennox and Addington (87.2 cases per 100,000), Hastings and Prince Edward Counties (28.6 cases per 100,000), Ottawa (18.1 cases per 100,000) and Eastern Ontario (13.5 cases per 100,000). Cases occurred mostly from June through September, were most common among males, and those aged 5-14 and 50-69 years. CONCLUSION: In 2017, Lyme disease incidence showed a marked increase in Ontario, especially in the eastern part of the province. If current weather and climate trends continue, blacklegged ticks carrying tick-borne pathogens, such as those causing Lyme disease, will continue to spread into suitable habitat. Monitoring the extent of this geographic spread will inform future clinical and public health actions to detect and mitigate the impact of Lyme disease in Ontario.

14.
Pediatr Obes ; 13(7): 406-412, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29700995

RESUMO

BACKGROUND: Sleep has emerged as a potentially modifiable risk factor for obesity in children. OBJECTIVES: The purpose of this investigation was to evaluate the association between overnight sleep duration and obesity among American Indian (AI) children ages 2-5 years. METHODS: Data were examined from the baseline assessment of children enrolling in the Healthy Children, Strong Families study, which is a randomized lifestyle intervention trial in five diverse rural and urban AI communities nationally among children ages 2-5 years. Multivariable models were built to assess the relationship between sleep duration and BMI z-score while controlling for potential sociodemographic and behavioural covariates. RESULTS: Three hundred and ninety-eight children had sufficient data to be included in analysis. In multivariable models controlling for potential covariates, overnight sleep duration was significantly and inversely associated with BMI z-score (B = -0.158, t = -1.774, P = 0.006). Similarly, when controlling for covariates, children who slept 12 or more hours had significantly lower BMI z-scores compared with those who slept 8 to 10 h (P = 0.018) or less than 8 h (P = 0.035); the difference between 12+ hours and 10 to 12-h groups did not reach statistical significance (P = 0.073) but supported a linear relationship between overnight sleep duration and BMI. Weekday-to-weekend variability in overnight sleep duration was not associated with BMI z-score (B = 0.010, t = 0.206, P = 0.837). CONCLUSIONS: Overnight sleep duration is independently and inversely related to BMI z-score among AI children ages 2-5 years, even when controlling for important sociodemographic and obesogenic lifestyle factors. This represents the first report, to our knowledge, of sleep duration as a risk factor for obesity among AI children.


Assuntos
Indígenas Norte-Americanos , Obesidade Infantil/etiologia , Sono , Índice de Massa Corporal , Pré-Escolar , Feminino , Humanos , Estilo de Vida , Masculino , Fatores de Risco , Fatores de Tempo
15.
FASEB J ; 20(3): 565-7, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16436466

RESUMO

We have developed a chamber model of islet engraftment that optimizes islet survival by rapidly restoring islet-extracellular matrix relationships and vascularization. Our aim was to assess the ability of syngeneic adult islets seeded into blood vessel-containing chambers to correct streptozotocin-induced diabetes in mice. Approximately 350 syngeneic islets suspended in Matrigel extracellular matrix were inserted into chambers based on either the splenic or groin (epigastric) vascular beds, or, in the standard approach, injected under the renal capsule. Blood glucose was monitored weekly for 7 weeks, and an intraperitoneal glucose tolerance test performed at 6 weeks in the presence of the islet grafts. Relative to untreated diabetic animals, glycemic control significantly improved in all islet transplant groups, strongly correlating with islet counts in the graft (P<0.01), and with best results in the splenic chamber group. Glycemic control deteriorated after chambers were surgically removed at week 8. Immunohistochemistry revealed islets with abundant insulin content in grafts from all groups, but with significantly more islets in splenic chamber grafts than the other treatment groups (P<0.05). It is concluded that hyperglycemia in experimental type 1 diabetes can be effectively treated by islets seeded into a vascularized chamber functioning as a "pancreatic organoid."


Assuntos
Glicemia/análise , Diabetes Mellitus Experimental/cirurgia , Transplante das Ilhotas Pancreáticas/instrumentação , Engenharia Tecidual/instrumentação , Transplante Heterotópico/instrumentação , Animais , Colágeno , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Combinação de Medicamentos , Teste de Tolerância a Glucose , Sobrevivência de Enxerto , Virilha , Insulina/uso terapêutico , Rim , Laminina , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica , Proteoglicanas , Baço , Transplante Homólogo
16.
J Hosp Infect ; 96(2): 111-115, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28389093

RESUMO

BACKGROUND: Reports of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-Kp) in Australia were previously uncommon, with cases imported sporadically by travellers from higher prevalence countries. AIM: The study institution reported the first outbreak of KPC-Kp in Australia. The aim of this study was to identify risk factors for KPC-Kp colonization and infection using a matched case-control study. METHODS: The study included all hospitalized patients with KPC-Kp colonization or infection from January 2012 to September 2015. FINDINGS: Thirty-four cases of KPC-producing Enterobacteriaceae (including 31 KPC-Kp cases) were matched with 136 controls. Variables associated with KPC-Kp acquisition included: length of hospital stay >28 days in the past 12 months, prior vancomycin-resistant enterococci (VRE) colonization, central venous catheter (CVC), gastrointestinal disease and invasive procedures. Exposure to broad-spectrum antibiotics was also found to be a significant risk factor. In the multi-variate analysis, three factors independently associated with KPC-Kp acquisition were length of hospital stay >28 days in the past 12 months [odds ratio (OR) 23.6, 95% confidence interval (CI) 4.9-113.3], presence of a CVC (OR 15.4, 95% CI 2.7-86.9), and prior VRE colonization (OR 6.0, 95% CI 1.6-23.2). Very few patients had a history of overseas travel. CONCLUSION: This study demonstrates that patients with prolonged hospital exposure are more likely to acquire KPC-Kp in the setting of a local outbreak, and suggests that risk factors for KPC-Kp acquisition may be shared with those for VRE colonization. Local screening strategies targeting overseas travellers would likely miss many cases. The results of this study will help to inform screening policies for carbapenemase-producing Enterobacteriaceae.


Assuntos
Proteínas de Bactérias/metabolismo , Portador Sadio/epidemiologia , Infecção Hospitalar/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/enzimologia , beta-Lactamases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Portador Sadio/microbiologia , Estudos de Casos e Controles , Enterobacteriaceae/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
17.
J Natl Cancer Inst ; 90(7): 498-504, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9539244

RESUMO

This review summarizes methodologic theories for the design of cancer screening case-control studies and examines the methods applied in studies published in English from 1980 through 1996. In addition to summarizing state-of-the-art methodologic approaches, we identify areas where obvious gaps exist between theory and practice, and we recommend potential areas where theory and methodology may need further development. In particular, we focus on three major areas: 1) the selection of case and control subjects, 2) the definition of exposure (i.e., exposure to the screening test), and 3) bias. Each area is considered carefully by summarizing current theory, reviewing cancer screening applications, and linking recommended methodologic approaches to those used in practice to identify areas where inconsistencies exist. In general, we found methodologic theory and practice in this field of research to be consistent. However, discrepancies were identified in the area of exposure definition, including the use of screening frequency and the use of a detectable, curable preclinical phase for case subjects as the exposure measures. Even when recommended methods were followed, a number of difficulties arose in practice. Specific concerns included the ability to carry out the following: identifying all case subjects within a source population, defining eligibility criteria to ensure that case and control subjects had equal access to screening during the exposure period, distinguishing between symptomatic and diagnostic tests, and controlling for self-selection bias. Careful scrutiny is warranted in all aspects of the design of cancer screening case-control studies, and caution is advised in the interpretation of study results.


Assuntos
Programas de Rastreamento/métodos , Neoplasias/diagnóstico , Neoplasias/prevenção & controle , Projetos de Pesquisa , Estudos de Casos e Controles , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Valor Preditivo dos Testes
18.
J Natl Cancer Inst ; 91(12): 1033-9, 1999 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-10379966

RESUMO

BACKGROUND: The objective of this study was to investigate the circumstances under which dissemination of prostate-specific antigen (PSA) testing, beginning in 1988, could plausibly explain the declines in prostate cancer mortality observed from 1992 through 1994. METHODS: We developed a computer simulation model by use of information on population-based PSA testing patterns, cancer detection rates, average lead time (the time by which diagnosis is advanced by screening), and projected decreased risk of death associated with early diagnosis of prostate cancer through PSA testing. The model provides estimates of the number of deaths prevented by PSA testing for the 7-year period from 1988 through 1994 and projects what prostate cancer mortality for these years would have been in the absence of PSA testing. RESULTS: Results were generated by assuming a level of screening efficacy similar to that hypothesized for the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Under this assumption, the projected mortality in the absence of PSA testing continued the increasing trend observed before 1991 only when it was assumed that the mean lead time was 3 years or less. Projected mortality trends in the absence of PSA screening were not consistent with pre-1991 increasing trends for lead times of 5 years and 7 years. CONCLUSIONS: When screening is assumed to be at least as efficacious as hypothesized in the PLCO trial, it is unlikely that the entire decline in prostate cancer mortality can be explained by PSA testing based on current beliefs concerning lead time. Only very short lead times would produce a decline in mortality of the magnitude that has been observed.


Assuntos
Programas de Rastreamento , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/mortalidade , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Simulação por Computador , Humanos , Masculino , Programas de Rastreamento/métodos , Modelos Estatísticos , Mortalidade/tendências , Vigilância da População , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/imunologia , Taxa de Sobrevida , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos
19.
J Natl Cancer Inst ; 86(10): 785-91, 1994 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-8169977

RESUMO

BACKGROUND: Previous studies have suggested that some of the limitations associated with the administration of high-dose exogenous interleukin 2 (IL2) may be overcome, at least partly, by cytokine gene transfer modalities. These findings have prompted investigations into whether human tumor cells may be transduced with the IL2 gene and whether tumor cell lines could be engineered to release IL2. PURPOSE: The purpose of this study was to evaluate the possibility of inducing a productive transfer of the IL2 gene into human acute leukemia cells and to assess the phenotypic and proliferative changes generated in the engineered cells, as well as their tumorigenic potential in nude mice. METHODS: Three retroviral vectors (DC/TK/IL2, DC/AD/R/IL2, and N2/CMV/IL2) carrying the IL2 gene were used to transduce three human leukemic cell lines: K562 and U937 (myeloid) and ST4 (lymphoid). Messenger RNA expression of the IL2 gene was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) and productive IL2 release using a human IL2 assay and an enzyme-linked immunosorbent assay kit. The expression of the p55 (alpha) and p75 (beta) chains of the IL2 receptor were determined by RT-PCR and indirect immunofluorescence. The kinetics of in vitro growth and proliferation of parental and engineered cells were also measured. Parental and IL2 gene-transduced ST4 lymphoblasts were injected into immunosuppressed nude mice that had their tumors measured twice weekly. RESULTS: The productive insertion of the IL2 gene was achieved in all three cell lines studied. The amounts of IL2 constitutively released by the engineered neoplastic cells ranged between 1 and 11 U/mL of IL2 produced from 10(6) cells in 72 hours. A fivefold increase in IL2 production was obtained in ST4 cells by further limiting dilution cloning of the bulk-infected cells. The stable integration of the IL2 gene did not modify the phenotype of the leukemic cells, the expression of the IL2 receptor alpha and beta chains and of several cytokine genes, or the kinetics of in vitro growth and proliferation. In nude mice injected with various IL2-producing ST4 clones, tumor growth associated inversely with the amounts of IL2 secreted by the leukemic cells. CONCLUSIONS: The results of this study demonstrate that the IL2 gene can be productively transduced into human myeloid and lymphoid leukemic cells without modifying their phenotypic and proliferative properties and that this transduction leads to a reduced or abrogated in vivo tumorigenic potential.


Assuntos
Terapia Genética/métodos , Interleucina-2/genética , Leucemia/terapia , Doença Aguda , Animais , Divisão Celular/genética , Feminino , Expressão Gênica , Vetores Genéticos , Humanos , Interleucina-2/biossíntese , Leucemia/imunologia , Camundongos , Camundongos Nus , Vírus da Leucemia Murina de Moloney , RNA Mensageiro/biossíntese , Receptores de Interleucina-2/genética , Fatores de Tempo , Células Tumorais Cultivadas
20.
Cancer Res ; 50(24): 7820-5, 1990 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-2123742

RESUMO

Retroviral vectors were used to introduce the gamma-interferon (IFN-gamma) gene into CMS-5 cells, a weakly immunogenic tumor of BALB/c origin. After selection in G418-containing medium, colonies were isolated, cloned, and expanded to cell lines. IFN-gamma secretion was assessed using a bioassay and enzyme-linked immunosorbent assay, and high (25 units/ml) and low (5 units/ml) IFN-gamma producers were isolated. Tumor growth was followed after intradermal injection, and spleen cells were isolated at different time points. IFN-gamma secretion by tumor cells abrogated their tumorigenicity and induced a persistent and specific antitumor immunity. In contrast to the normally observed cellular immunosuppression in unmodified CMS-5 tumor-bearing mice, IFN-gamma-producing tumors induced a long lasting state of T-cell immunity, as judged by rejection of a CMS-5 tumor challenge and persistence of specific cytotoxic activity in the spleen cell population. High levels of tumor-specific cytotoxic activity could also be detected if IFN-gamma-secreting tumor cells, but not unmodified CMS-5 cells, were used as targets at a time point when immunosuppression was usually seen. These studies highlight the potential advantages of localized IFN-gamma secretion to induce potent antitumor immune responses.


Assuntos
Fibrossarcoma/imunologia , Vetores Genéticos , Interferon gama/genética , Vírus da Leucemia Murina de Moloney/genética , Transfecção , Animais , Divisão Celular , Linhagem Celular , DNA/genética , Ensaio de Imunoadsorção Enzimática , Fibrossarcoma/patologia , Tolerância Imunológica , Interferon gama/biossíntese , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos , Regiões Promotoras Genéticas
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