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1.
JNCI Cancer Spectr ; 8(3)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38730548

RESUMO

BACKGROUND: Traditional constraints specify that 700 cc of liver should be spared a hepatotoxic dose when delivering liver-directed radiotherapy to reduce the risk of inducing liver failure. We investigated the role of single-photon emission computed tomography (SPECT) to identify and preferentially avoid functional liver during liver-directed radiation treatment planning in patients with preserved liver function but limited functional liver volume after receiving prior hepatotoxic chemotherapy or surgical resection. METHODS: This phase I trial with a 3 + 3 design evaluated the safety of liver-directed radiotherapy using escalating functional liver radiation dose constraints in patients with liver metastases. Dose-limiting toxicities were assessed 6-8 weeks and 6 months after completing radiotherapy. RESULTS: All 12 patients had colorectal liver metastases and received prior hepatotoxic chemotherapy; 8 patients underwent prior liver resection. Median computed tomography anatomical nontumor liver volume was 1584 cc (range = 764-2699 cc). Median SPECT functional liver volume was 1117 cc (range = 570-1928 cc). Median nontarget computed tomography and SPECT liver volumes below the volumetric dose constraint were 997 cc (range = 544-1576 cc) and 684 cc (range = 429-1244 cc), respectively. The prescription dose was 67.5-75 Gy in 15 fractions or 75-100 Gy in 25 fractions. No dose-limiting toxicities were observed during follow-up. One-year in-field control was 57%. One-year overall survival was 73%. CONCLUSION: Liver-directed radiotherapy can be safely delivered to high doses when incorporating functional SPECT into the radiation treatment planning process, which may enable sparing of lower volumes of liver than traditionally accepted in patients with preserved liver function. TRIAL REGISTRATION: NCT02626312.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Fígado , Radioterapia Guiada por Imagem , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Masculino , Feminino , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/diagnóstico por imagem , Pessoa de Meia-Idade , Idoso , Fígado/diagnóstico por imagem , Fígado/efeitos da radiação , Radioterapia Guiada por Imagem/métodos , Neoplasias Colorretais/radioterapia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/diagnóstico por imagem , Tamanho do Órgão , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto
2.
Endosc Ultrasound ; 9(1): 24-30, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31670288

RESUMO

Current treatment options for patients with unresectable locally advanced pancreatic cancer (LAPC) include chemotherapy alone or followed by chemoradiation or stereotactic body radiotherapy. However, the prognosis for these patients remains poor, with a median overall survival <12 months. Therefore, novel treatment options are needed. Currently, there is no brachytherapy device approved for pancreatic cancer treatment. Hereby, we present the protocol of a prospective, multicenter, interventional, open-label, single-arm pilot study (OncoPac-1, Clinicaltrial.gov-NCT03076216) aiming to determine the safety and efficacy of Phosphorus-32 when implanted directly into pancreatic tumors using EUS guidance, for patients with unresectable LAPC undergoing chemotherapy (gemcitabine ± nab-paclitaxel).

4.
Am J Addict ; 27(1): 23-28, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29251380

RESUMO

BACKGROUND AND OBJECTIVES: Prior research has revealed a strong relationship between Posttraumatic Stress Disorder (PTSD) and alcohol misuse. However, previous attempts to understand nuanced associations between PTSD symptom clusters and alcohol misuse within military veteran samples have produced mixed results. In an attempt to better understand the associations between PTSD and alcohol misuse, the current study examined the unique relationships between the newly classified Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) PTSD symptom clusters and alcohol misuse in an outpatient sample of military veterans seeking treatment for PTSD and Substance Use Disorders. METHODS: Veterans (N = 100) were administered a brief battery of self-report questionnaires prior to receiving psychological services to aid in diagnostic assessment and treatment planning. RESULTS: Hierarchical regression analyses revealed that PTSD intrusions (cluster B), negative alterations in cognition and mood (cluster D), and arousal/reactivity (cluster E) symptoms were associated with alcohol misuse. DISCUSSION AND CONCLUSIONS: The positive association between alcohol misuse and PTSD symptom severity is consistent with a broader body of literature demonstrating the co-occurrence of these disorders, particularly in military samples. SCIENTIFIC SIGNIFICANCE: Increased alcohol consumption may interfere with current front-line treatments for PTSD, which encourages patients to experience a full range of emotions. As such, future research should explore the impact of substance use on the effectiveness of trauma focused treatments in the alleviation of DSM-5 PTSD symptoms. (Am J Addict 2018;27:23-28).


Assuntos
Transtornos Relacionados ao Uso de Álcool/etiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Veteranos/psicologia , Adulto , Idoso , Transtornos Relacionados ao Uso de Álcool/diagnóstico , Transtornos Relacionados ao Uso de Álcool/psicologia , Estudos Transversais , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Fatores de Risco , Autorrelato , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Adulto Jovem
5.
Kidney Int ; 71(10): 985-93, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17361118

RESUMO

In chronic renal disease, the progressive accumulation of collagen and other extracellular matrix proteins in the mesangium results in fibrosis, glomerulosclerosis, and eventual renal failure. Mice deficient in proalpha2(I) collagen are not only a model of osteogenesis imperfecta but also accumulate fibrillar homotrimeric type I collagen in the mesangium. This accumulation spreads to the subendothelial space in the peripheral capillary loops. Picosirius red staining of kidney sections demonstrates that in comparison to wild-type mice, Col1a2-deficient homozygous and heterozygous mice exhibit abnormal glomerular collagen deposition in a gene dosage-dependent manner. The glomerulopathy initiates during the first postnatal week, appears progressive following the pattern of glomerular maturation and results in albuminuria in severely affected animals. In situ hybridization revealed no gross differences in steady-state proalpha1(I) and proalpha2(I) collagen mRNA levels among the three genotypes. Quantitative reverse transcriptase-polymerase chain reaction, however, using whole kidney sections showed a twofold increase in steady-state proalpha1(I) collagen mRNA in 1-month homozygous Col1a2-deficient animals compared with wild-type and heterozygous animals. We suggest that glomerular collagen deposition seen in the osteogenesis imperfecta model mice is, in part, owing to pretranslational mechanisms and may represent an over compensation of wound healing.


Assuntos
Animais Recém-Nascidos/metabolismo , Colágeno Tipo I/metabolismo , Colágeno/deficiência , Nefropatias/etiologia , Nefropatias/fisiopatologia , Glomérulos Renais/crescimento & desenvolvimento , Albuminúria/etiologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Colágeno/genética , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Heterozigoto , Homeostase , Nefropatias/metabolismo , Nefropatias/patologia , Glomérulos Renais/patologia , Camundongos , Camundongos Knockout , Microscopia Eletrônica , RNA Mensageiro/metabolismo
6.
J Neuroophthalmol ; 24(1): 19-23, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15206433

RESUMO

BACKGROUND: Epilepsy surgery involves well-planned discrete injury to the brain and may create visual deficits. This study seeks to evaluate the indirect effects of temporal lobectomy on brain metabolism by correlating visual field defects and glucose metabolism in the visual cortex of patients before and after undergoing epilepsy surgery. METHODS: A retrospective survey of 11 patients who had undergone temporal lobectomy for refractory epilepsy in a single institution from 1986 to 1989, and who had pre-lobectomy and post-lobectomy visual field examinations and F-18 2-fluorodeoxyglucose positron emission tomography (FDG-PET) as part of a standard comprehensive epilepsy surgery evaluation. The PET images were analyzed to provide a correlation with the visual field defects that developed after the temporal lobectomy. RESULTS: Occipital hypometabolism in the absence of structural lesions of the occipital lobe was noted in seven patients with contralateral visual field defects and in one of four patients without a visual field defect. FDG-PET studies in three patients repeated for as long as 20 months after lobectomy showed no significant change in the occipital hypometabolism pattern. CONCLUSIONS: Although the occipital cortex was not directly injured during temporal lobectomy, the resulting hypometabolism correlates with the clinical findings of visual field defects. The hypometabolism may be due to deafferentation after interruption of the optic pathways and appears to be persistent.


Assuntos
Epilepsia do Lobo Temporal/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/metabolismo , Lobo Temporal/cirurgia , Tomografia Computadorizada de Emissão , Adulto , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Fatores de Tempo
7.
Gut ; 49(5): 656-64, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11600468

RESUMO

AIM: We evaluated the effect of coadministration of sulphasalazine, mesalamine, and balsalazide on the pharmacokinetics and pharmacodynamics of azathioprine and 6-mercaptopurine. METHODS: Thirty four patients with Crohn's disease receiving azathioprine or 6-mercaptopurine were enrolled in an eight week non-randomised parallel group drug interaction study and treated with mesalamine 4 g/day, sulphasalazine 4 g/day, or balsalazide 6.75 g/day. The primary outcome measure was the occurrence of clinically important leucopenia during the study, defined separately as total leucocyte counts < 3.0 x 10(9)/l and < or = 3.5 x 10(9)/l. Whole blood 6-thioguanine nucleotide concentrations were determined. RESULTS: Three patients could not be evaluated for the primary outcome measure. In the remaining 31 patients, the frequency of total leucocyte counts < 3.0 and < or = 3.5 were: 1/10 and 5/10 in the mesalamine group; 1/11 and 6/11 in the sulphasalazine group; and 0/10 and 2/10 in the balsalazide group. There were significant increases in mean whole blood 6-thioguanine nucleotide concentrations from baseline at most time points in the mesalamine and sulphasalazine groups but not in the balsalazide group. CONCLUSIONS: In patients with Crohn's disease receiving azathioprine or 6-mercaptopurine, coadministration of mesalamine, sulphasalazine, and possibly balsalazide results in an increase in whole blood 6-thioguanine nucleotide concentrations and a high frequency of leucopenia.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Imunossupressores/efeitos adversos , Leucopenia/induzido quimicamente , Adulto , Ácidos Aminossalicílicos/efeitos adversos , Análise de Variância , Azatioprina/efeitos adversos , Distribuição Binomial , Cromatografia Líquida de Alta Pressão , Intervalos de Confiança , Interações Medicamentosas , Feminino , Humanos , Leucopenia/metabolismo , Masculino , Mercaptopurina/efeitos adversos , Mesalamina/efeitos adversos , Metiltransferases/sangue , Fenil-Hidrazinas , Sulfassalazina/efeitos adversos , Tioguanina/análise
8.
Gut ; 49(5): 665-70, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11600469

RESUMO

BACKGROUND: Measurement of 6-thioguanine nucleotide concentrations may be useful for optimising treatment with azathioprine and 6-mercaptopurine. METHODS: We conducted a study of 170 patients with inflammatory bowel disease treated with azathioprine or 6-mercaptopurine to determine the relationship between 6-thioguanine nucleotide concentrations and both disease activity, as measured by the inflammatory bowel disease questionnaire (active disease < 170, remission > or = 170) and leucopenia. Blood was submitted for whole blood 6-thioguanine nucleotide concentration and leucocyte count. RESULTS: Mean (SD) inflammatory bowel disease questionnaire score was 176 (32). There was no correlation between inflammatory bowel disease questionnaire scores and 6-thioguanine nucleotide concentrations (r(s) = -0.09, p = 0.24). Median 6-thioguanine nucleotide concentrations in 56 patients with active disease and 114 patients in remission were similar (139 v 131 pmol/8 x 10(8) red blood cells; p = 0.26). There was no correlation between 6-thioguanine nucleotide concentrations and leucocyte counts. CONCLUSIONS: In patients with inflammatory bowel disease treated with azathioprine or 6-mercaptopurine, 6-thioguanine nucleotide concentrations did not correlate with disease activity, as measured by the inflammatory bowel disease questionnaire, or leucocyte count. These findings are discrepant with most previous studies, possibly due to selection of responding patients who tolerated the medications. A prospective, randomised, dose optimisation trial using 6-thioguanine nucleotide concentrations is warranted.


Assuntos
Azatioprina/sangue , Imunossupressores/sangue , Doenças Inflamatórias Intestinais/tratamento farmacológico , Metiltransferases/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Azatioprina/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/sangue , Leucopenia/induzido quimicamente , Masculino , Mercaptopurina/sangue , Mercaptopurina/uso terapêutico , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Estatísticas não Paramétricas
9.
J Clin Microbiol ; 39(11): 3920-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11682508

RESUMO

Over the past decade, several Helicobacter species have been isolated from rodents. With the advent of PCR for the diagnosis of infectious agents, it has become clear that several previously uncharacterized Helicobacter species also colonize rodents. In this report, we describe a novel urease-negative helicobacter, Helicobacter typhlonius sp. nov., which was isolated from colonies of laboratory mice independently by two laboratories. Infection of immunodeficient mice by this bacterium resulted in typhlocolitis similar to that observed with other helicobacter infections. H. typhlonius is genetically most closely related to H. hepaticus. Like H. hepaticus, it is a spiral bacterium with bipolar sheathed flagella. However, this novel species contains a large intervening sequence in its 16S rRNA gene and is biochemically distinct from H. hepaticus. Notably, H. typhlonius does not produce urease or H(2)S nor does it hydrolize indoxyl-acetate. Compared to other Helicobacter species that commonly colonize rodents, H. typhlonius was found to be less prevalent than H. hepaticus and H. rodentium but as prevalent as H. bilis. H. typhlonius joins a growing list of helicobacters that colonize mice and are capable of inducing enteric disease in various strains of immunodeficient mice.


Assuntos
Animais de Laboratório , Infecções por Helicobacter/veterinária , Helicobacter/classificação , Doenças dos Roedores/microbiologia , Urease/metabolismo , Animais , Genes de RNAr , Helicobacter/enzimologia , Helicobacter/genética , Infecções por Helicobacter/microbiologia , Interleucina-10/genética , Intestinos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
J Nerv Ment Dis ; 189(8): 548-51, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11531207

RESUMO

Studies of posttraumatic stress disorder (PTSD) have found high levels of comorbid major depressive disorder (MDD). One reason suggested for the comorbidity is the symptom overlap (contaminated symptoms) between the disorders. The present study investigated the contribution of contaminated symptoms (anhedonia, concentration, and sleep problems) to the comorbidity of PTSD and MDD. PTSD symptoms were subdivided into two groups: the contaminated symptoms and the 14 unique symptoms. It was speculated that if the contaminated symptoms are responsible for the comorbidity, then they will show less specificity than the unique symptoms, will be less highly correlated with a PTSD symptom total count, and be more frequently endorsed in PTSD patients with than without MDD. These hypotheses were tested in a sample (N = 1300) of psychiatric outpatients, 260 of whom had lifetime PTSD. None of the hypotheses were supported, thereby suggesting that the comorbidity between PTSD and MDD is not an artifact of symptom overlap.


Assuntos
Transtorno Depressivo/diagnóstico , Transtorno Depressivo/epidemiologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Adolescente , Adulto , Idoso , Assistência Ambulatorial , Especificidade de Anticorpos , Distribuição de Qui-Quadrado , Comorbidade , Transtorno Depressivo/psicologia , Diagnóstico Diferencial , Feminino , Humanos , Acontecimentos que Mudam a Vida , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Psicometria , Reprodutibilidade dos Testes , Transtornos de Estresse Pós-Traumáticos/psicologia
11.
Vet Pathol ; 38(4): 441-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11467479

RESUMO

An approximately 8-week-old pet Syrian hamster (Mesocricetus auratus) with a 1-week history of dyspnea, hyporexia, and ataxia was submitted for necropsy. On gross examination, the hamster had multiple abdominal adhesions and enlargement of the mesenteric lymph node. Histologic evaluation revealed multicentric lymphoma of the liver, jejunum, mesenteric lymph node, testicular fat pad, and epididymis. Based on the hamster's age and the type and distribution of the lymphoma, a presumptive diagnosis of hamster polyomavirus-induced lymphoma was made. A specific polymerase chain reaction (PCR) was developed, which confirmed the diagnosis. An in situ PCR demonstrated hamster polyomavirus DNA within lymphocytes of the multicentric lymphoma and renal tubular epithelial cells and within clusters of enterocytes in the jejunum. These data are consistent with environmental dissemination of hamster polyomavirus virions through the renal tubular epithelium and into the urine and with fecal shedding of hamster polyomavirus virions; however, additional studies will be needed to confirm these observations.


Assuntos
Linfoma/veterinária , Mesocricetus , Infecções por Polyomavirus/veterinária , Polyomavirus/isolamento & purificação , Doenças dos Roedores/virologia , Infecções Tumorais por Vírus/veterinária , Animais , Cricetinae , DNA Viral/química , DNA Viral/isolamento & purificação , Evolução Fatal , Histocitoquímica/veterinária , Jejuno/patologia , Jejuno/virologia , Rim/patologia , Rim/virologia , Linfoma/patologia , Linfoma/virologia , Masculino , Reação em Cadeia da Polimerase/veterinária , Polyomavirus/genética , Infecções por Polyomavirus/patologia , Infecções por Polyomavirus/virologia , Doenças dos Roedores/patologia , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/virologia
12.
J Chromatogr B Biomed Sci Appl ; 757(1): 1-9, 2001 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-11419732

RESUMO

The conversion of the cytotoxic and immunosuppressive 6-mercaptopurine (6MP) to the active 6-thioguanine nucleotides (6TGN) is necessary for clinical efficacy of 6MP and its prodrug azathioprine. Another metabolite, 6-methylmercaptopurine nucleotide (6MMPN), is formed via a competing pathway by thiopurine methyl transferase. The concentrations of 6TGN and 6MMPN are measured in washed erythrocytes as a surrogate to the intracellular levels of these metabolites in the target tissues. Analysis of 6TGN and 6MMPN in multi-center clinical studies is more complicated because of the requirement to wash erythrocytes. In this investigation, we found no differences in the concentrations of 6TGN and 6MMPN in blood versus washed erythrocytes in samples obtained from patients taking therapeutic doses of oral 6MP or azathioprine for inflammatory bowel disease. We concluded that whole blood could be used for the analysis of these analytes, thus saving sample preparation time. We also found that the erythrocyte 6TGN concentration in blood at ambient temperature declined 2-4% per day, a loss that can be avoided by shipping blood samples frozen. The loss of 6TGN in blood stored at approximately -80 degrees C was 1% after 1 week and 12% after 24 weeks, indicating the analyte was moderately stable. 6MMPN in blood did not significantly change after 24 weeks of storage at approximately -80 degrees C. In addition, the sensitivity of the 6TGN assay was improved by modifying the HPLC conditions, which made the method more suitable for quantifying low levels of 6TGN in human intestinal biopsy samples and blood.


Assuntos
Mercaptopurina/análogos & derivados , Mercaptopurina/sangue , Tioguanina/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mercaptopurina/uso terapêutico , Reprodutibilidade dos Testes , Espectrometria de Fluorescência , Tioguanina/uso terapêutico
13.
Contemp Top Lab Anim Sci ; 40(3): 43, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11353526
14.
Infect Immun ; 69(6): 3697-702, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11349033

RESUMO

The cilium-associated respiratory (CAR) bacillus is a gram-negative, extracellular bacterium that causes persistent respiratory tract infections in rodents. We have previously demonstrated that BALB/c mice are more susceptible to CAR bacillus-induced disease than resistant C57BL/6 mice, with elevations in pulmonary gamma interferon (IFN-gamma) and interleukin (IL)-4. IL-10 is a type 2 cytokine that can increase host susceptibility to bacterial diseases through its anti-inflammatory effects, including suppression of macrophage function. The purpose of this study was to further describe the cytokine profiles associated with histologic lesions in CAR bacillus-infected mice and to assess the effects of cytokine depletion on the pathogenesis of disease. Six-week-old female BALB/c and C57BL/6 mice and mice with targeted mutations in IFN-gamma and IL-4 were inoculated intratracheally with 10(5) CAR bacillus organisms, and samples were collected at 6 to 7 weeks postinoculation. Lung samples were collected for histopathologic examination and analysis of cytokine mRNA. IFN-gamma, IL-10, and IL-4 mRNA levels in the lungs of infected mice were semiquantitatively measured using a reverse transcriptase-mediated PCR assay and compared to those in uninfected control animals of each strain. BALB/c mice infected with CAR bacillus had a median lung lesion score of 6 and IL-10 and IL-4 mRNA levels were significantly elevated. The majority of C57BL/6 mice were resistant to disease characterized by lung lesions scores of 2 or less and a dominant IFN-gamma mRNA cytokine profile. A few C57BL/6 mice with lesions scores of 5 or greater had elevations in all three cytokines and were susceptible to disease. C57BL/6 IFN-gamma knockout mice had increased disease with elevations in IL-10 and IL-4 mRNA, while BALB/c IL-4 knockout mice infected with CAR bacillus had a mild decrease in lesion severity and an attenuated IL-10 mRNA expression compared to wild-type BALB/c mice. These data indicate that IL-10 and IL-4 predominate in CAR bacillus-induced histologic lesions in mice, while IFN-gamma may play a role in resistance to disease.


Assuntos
Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Interferon gama/metabolismo , Interleucina-10/metabolismo , Pulmão/imunologia , RNA Mensageiro/metabolismo , Animais , Suscetibilidade a Doenças , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/fisiopatologia , Interferon gama/genética , Interleucina-10/genética , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções Respiratórias/imunologia , Infecções Respiratórias/microbiologia , Infecções Respiratórias/fisiopatologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Comp Med ; 51(2): 145-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11922178

RESUMO

PURPOSE: Mouse polyoma virus and K virus are murine polyomaviruses frequently used in carcinogenicity and cellular biology studies in mice. These viruses can cause persistent infections, which increase the likelihood of transmission through transplantation of cells from infected mice. To identify polyomavirus-infected biological samples, several diagnostic polymerase chain reaction (PCR) assays were developed. METHODS: Polyomavirus-family and virus-specific PCR assays were designed and optimized for specificity and sensitivity. The generic (polyomavirus-family) PCR assay and mouse polyoma virus-specific assays were compared with the mouse bioassay for diagnosis of infected cellular samples. RESULTS: Specificity of the PCR assays was confirmed by testing a battery of other murine viruses. The mouse polyoma virus PCR test was the most sensitive assay, detecting as few as 2,000 copies of homologous virus. The K virus PCR assay was about eightfold less sensitive, and the generic PCR test was the least sensitive. Mouse polyoma virus and generic PCR assays amplified mouse polyoma virus in the inoculum and tissues from experimentally infected mice, and performed better than did the mouse bioassay. CONCLUSIONS: Results of this study confirm that PCR is a specific and sensitive method for detection of murine polyomaviruses in biological samples.


Assuntos
Linhagem Celular/virologia , DNA Viral/análise , Camundongos/virologia , Reação em Cadeia da Polimerase/métodos , Infecções por Polyomavirus/veterinária , Polyomavirus/isolamento & purificação , Infecções Tumorais por Vírus/veterinária , Animais , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Ciência dos Animais de Laboratório/métodos , Camundongos Endogâmicos BALB C , Camundongos Nus , Polyomavirus/genética , Polyomavirus/imunologia , Infecções por Polyomavirus/diagnóstico , Sensibilidade e Especificidade , Infecções Tumorais por Vírus/diagnóstico
16.
Comp Med ; 51(4): 357-60, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11924795

RESUMO

Two from a group of approximately 50 C.B-17 scid-bg mice were examined because of lethargy, dehydration, and rough coat. Three months prior to development of clinical signs of disease, mice of this study had been surgically implanted with fetal bovine liver, thymus, and lymph node. At necropsy, marked splenomegaly and mild hepatomegaly were observed in both animals. Large areas of necrosis and inflammation, with associated intracytoplasmic granular basophilic inclusions, were observed in histologic sections of multiple organs. Aerobic and anaerobic culturing of the liver yielded negative results. Six months after the initial case, four more reconstituted scid-bg mice from a different fetal donor had identical clinical, gross, and histologic signs of disease. To determine whether the basophilic inclusions represented an infective agent, 4-month-old immune-naive C.B-17 scid-bg mice were inoculated intraperitoneally with a liver and spleen homogenate from an affected mouse. Two weeks after inoculation, mice developed clinical signs of disease and lesions identical to those seen in the signal mice. On ultrastructural examination of the liver, pleomorphic bacteria were found in large cytoplasmic vacuoles of hepatocytes. Bacterial DNA was amplified from the liver, using primers that amplify a segment of the 16S rRNA gene from many bacterial species. Sequencing of the polymerase chain reaction (PCR) product revealed gene sequence identical to that of Coxiella burnetii, the agent of Q-fever. These results highlight the need to consider infective agents of the donor species when working with xenografted animals.


Assuntos
Coxiella burnetii/isolamento & purificação , Transplante de Tecido Fetal , Camundongos SCID/cirurgia , Complicações Pós-Operatórias/microbiologia , Febre Q/transmissão , Transplante Heterólogo , Abdome , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Coxiella burnetii/genética , DNA Bacteriano/análise , Microbiologia Ambiental , Contaminação de Equipamentos , Feminino , Hepatite Crônica/etiologia , Hepatite Crônica/microbiologia , Hepatite Crônica/patologia , Hospedeiro Imunocomprometido , Fígado/embriologia , Fígado/microbiologia , Transplante de Fígado , Linfonodos/embriologia , Linfonodos/microbiologia , Linfonodos/transplante , Camundongos , Camundongos SCID/microbiologia , Reação em Cadeia da Polimerase , Complicações Pós-Operatórias/patologia , Febre Q/microbiologia , Febre Q/patologia , Timo/embriologia , Timo/microbiologia , Timo/transplante , Quimeras de Transplante/microbiologia , Transplante Heterotópico
17.
Infect Immun ; 68(9): 4961-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10948111

RESUMO

The cilium-associated respiratory (CAR) bacillus is a gram-negative, gliding bacterium that causes persistent respiratory tract infections in rodents despite histologic and serologic evidence of a marked immune response. To assess humoral immunity and cytokine responses in CAR bacillus disease, 6-week-old female BALB/c and C57BL/6 mice were inoculated intratracheally with 10(5) CAR bacillus organisms. CAR bacillus-specific serum immunoglobulins (immunoglobulin M [IgM], IgG1, IgG2a, IgG2b, IgG3, and IgA) and local pulmonary cytokines (tumor necrosis factor alpha [TNF-alpha], gamma interferon [IFN-gamma], and interleukin-4 [IL-4]) were evaluated by enzyme-linked immunosorbent assay every 7 days for 49 days. BALB/c mice developed CAR bacillus-induced lesions early in the course of disease that became more severe with time. Correlating with increasing disease severity, BALB/c mice had elevations in all antibody isotypes tested, and elevations in pulmonary TNF-alpha, IFN-gamma, and IL-4. C57BL/6 mice developed mild lesions with mild increases in serum IgM, IgG1, IgG2b, and IgG3 levels and minimally detectable IgG2a and IgA. Cytokine perturbations were not detected in C57BL/6 mice. The persistence of infection in BALB/c mice with vigorous serum antibody responses and increased IFN-gamma and IL-4 responses suggests that humoral immunity and T-cell responses are ineffective at preventing CAR bacillus disease. Furthermore, the lackluster antibody responses and undetectable cytokine responses in C57BL/6 mice suggest that humoral immunity and T-cell responses are not critical in resistance to CAR bacillus-induced disease.


Assuntos
Anticorpos Antibacterianos/sangue , Citocinas/biossíntese , Bactérias Gram-Negativas/imunologia , Infecções Respiratórias/microbiologia , Animais , Feminino , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Imunoglobulina M/sangue , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mycoplasma/isolamento & purificação , Especificidade da Espécie
18.
J Org Chem ; 65(15): 4509-14, 2000 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10959851

RESUMO

The phospholipase C (PLC) isozymes catalyze the hydrolysis of phospholipids to provide diacylglycerol (DAG) and a phosphorylated headgroup. Because DAG has been implicated in cellular signal transduction cascades in mammalian systems, there has been considerable interest in the development of inhibitors of these enzymes. Toward this end, we have discovered that the cyclic N,N'-dihydroxyureas 6-10 inhibit the phosphatidylcholine preferring PLC from Bacillus cereus (PLCBc). This class of inhibitors is believed to function by the bidentate chelation of the N,N'-dihydroxyurea array to one or more of the zinc ions at the active site of the enzyme. Because the affinities of these compounds correlate with the pKaS of the N-OH hydroxyl groups, it is apparent that one or both of the hydroxyl groups must be ionized for effective coordination to the zinc ions. It is also apparent that there may be rather strict steric requirements for these inhibitors.


Assuntos
Bacillus cereus/enzimologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Fosfolipases Tipo C/antagonistas & inibidores , Zinco/metabolismo , Sítios de Ligação , Quelantes/química , Quelantes/metabolismo , Quelantes/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/metabolismo , Compostos Heterocíclicos/farmacologia , Hidroxiureia/análogos & derivados , Hidroxiureia/química , Hidroxiureia/metabolismo , Hidroxiureia/farmacologia , Fosfolipases Tipo C/química , Fosfolipases Tipo C/metabolismo
19.
J Clin Microbiol ; 38(5): 1811-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10790105

RESUMO

A spiral-shaped bacterium with bipolar, single, nonsheathed flagella was isolated from the feces of Syrian hamsters. The bacterium grew as a thin spreading film at 37 degrees C under microaerobic conditions, did not hydrolyze urea, was positive for catalase and alkaline phosphatase, reduced nitrate to nitrite, did not hydrolyze hippurate, and was sensitive to nalidixic acid but resistant to cephalothin. Sequence analysis of the 16S rRNA gene and biochemical and phenotypic criteria indicate that the novel bacterium is a helicobacter. The novel bacterium is most closely related to the recently described mouse enteric helicobacter, Helicobacter rodentium. This is the first urease-negative Helicobacter species with nonsheathed flagella isolated from feces of asymptomatic Syrian hamsters. We propose to name this novel helicobacter Helicobacter mesocricetorum. The type strain is MU 97-1514 (GenBank accession number AF072471).


Assuntos
Helicobacter/classificação , Mesocricetus/microbiologia , Filogenia , Fosfatase Alcalina/análise , Animais , Catalase/análise , Cefalotina/farmacologia , Cricetinae , Fezes/microbiologia , Flagelos/ultraestrutura , Helicobacter/isolamento & purificação , Helicobacter/ultraestrutura , Camundongos , Ácido Nalidíxico/farmacologia , Nitratos/metabolismo , RNA Ribossômico 16S/genética
20.
Lab Anim Sci ; 49(5): 496-505, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10551450

RESUMO

BACKGROUND AND PURPOSE: Several rodent helicobacters have been associated with chronic active hepatitis or inflammatory bowel disease. Severe combined immunodeficient (SCID) mice appear to be inherently susceptible to disease attributable to these emerging pathogens. With the advent of polymerase chain reaction (PCR) analysis, it has become clear that several as yet unidentified Helicobacter species may also colonize rodents, but their capacity to cause disease is unknown. METHODS: A Helicobacter species isolated from feces of a BALB/c mouse and provisionally named "H. typhlonicus" was used to inoculate helicobacter-free 4-week-old SCID mice (n = 11 males and 11 females). At various weeks after inoculation, mice were sacrificed and liver and intestinal specimens were collected for histologic examination and PCR analyses. RESULTS: The C.B-17 scid/scid mice inoculated with "H. typhlonicus" developed moderate to severe proliferative typhlocolitis, similar to that seen in SCID mice infected with H. hepaticus or H. bilis. However, in contrast to mice infected with H. hepaticus or H. bilis, lesions of chronic active hepatitis were not detected in mice inoculated with "H. typhlonicus." A similar disease syndrome developed in SCID mice cohabitated with B6D2F1 mice naturally infected with a novel Helicobacter species that was genetically identical to "H. typhlonicus." CONCLUSION: "Helicobacter typhlonicus" joins a growing list of helicobacters that are capable of inducing enteric disease in immunodeficient mice.


Assuntos
Colite/veterinária , Infecções por Helicobacter/veterinária , Helicobacter/isolamento & purificação , Doenças dos Roedores/microbiologia , Animais , Colite/microbiologia , Colite/patologia , DNA Bacteriano/análise , Fezes/microbiologia , Feminino , Helicobacter/enzimologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/transmissão , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Reação em Cadeia da Polimerase , Doenças dos Roedores/patologia , Urease/análise
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