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1.
J Neurovirol ; 29(5): 605-613, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37581843

RESUMEN

Encephalitis is a central nervous system disorder, often caused by infectious agents or aberrant immune responses. We investigated causes, comorbidities, costs, and outcomes of encephalitis in a population-based cohort. ICD-10 codes corresponding to encephalitis were used to identify health services records for all adults from 2004 to 2019. Data were cross-validated for identified diagnoses based on laboratory confirmation using univariate and multivariate statistical analyses. We identified persons with a diagnosis of encephalitis and abnormal cerebrospinal fluid (CSF) results (n = 581) in whom viral genome was detected (n = 315) in a population of 3.2 million adults from 2004 to 2019. Viral genome-positive CSF samples included HSV-1 (n = 133), VZV (n = 116), HSV-2 (n = 34), enterovirus (n = 4), EBV (n = 5), and CMV (n = 3) with the remaining viruses included JCV (n = 12) and HHV-6 (n = 1). The mean Charlson Comorbidity Index (2.0) and mortality rate (37.6%) were significantly higher in the CSF viral genome-negative encephalitis group although the mean costs of care were significantly higher for the CSF viral genome-positive group. Cumulative incidence rates showed increased CSF VZV detection in persons with encephalitis, which predominated in persons over 65 years with a higher mean Charlson index. We detected HSV-2 and VZV more frequently in CSF from encephalitis cases with greater material-social deprivation. The mean costs of care were significantly greater for HSV-1 encephalitis group. Encephalitis remains an important cause of neurological disability and death with a viral etiology in 54.2% of affected adults accompanied by substantial costs of care and mortality. Virus-associated encephalitis is evolving with increased VZV detection, especially in older persons.


Asunto(s)
Encefalitis Viral , Herpesvirus Humano 1 , Virus , Adulto , Humanos , Anciano , Anciano de 80 o más Años , Herpesvirus Humano 1/genética , Comorbilidad , Encefalitis Viral/diagnóstico , Encefalitis Viral/epidemiología , Encefalitis Viral/líquido cefalorraquídeo , Herpesvirus Humano 2/genética , ADN Viral/genética , Herpesvirus Humano 3/genética
2.
J Neurovirol ; 27(3): 476-481, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33978904

RESUMEN

Neurological disorders associated with chronic infections are often progressive as well as challenging to diagnose and manage. Among 4.4 million persons from 2004 to 2019 receiving universal health, progressive multifocal leukoencephalopathy (PML, n = 58) and Creutzfeldt-Jakob disease (CJD, n = 93) cases were identified, revealing stable yearly incidence rates with divergent comorbidities: HIV/AIDS affected 37.8% of PML cases while cerebrovascular disease affected 26.9% of CJD cases. Most CJD cases died within 1 year (73%) although PML cases lived beyond 5 years (34.1%) despite higher initial costs of care. PML and CJD represent important neurological disorders with evolving risk variables and impact on health care.


Asunto(s)
Trastornos Cerebrovasculares/epidemiología , Costo de Enfermedad , Síndrome de Creutzfeldt-Jakob/epidemiología , Infecciones por VIH/epidemiología , Leucoencefalopatía Multifocal Progresiva/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Alberta/epidemiología , Trastornos Cerebrovasculares/diagnóstico , Trastornos Cerebrovasculares/economía , Trastornos Cerebrovasculares/mortalidad , Enfermedad Crónica , Comorbilidad , Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/economía , Síndrome de Creutzfeldt-Jakob/mortalidad , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/economía , Infecciones por VIH/mortalidad , Humanos , Incidencia , Leucoencefalopatía Multifocal Progresiva/diagnóstico , Leucoencefalopatía Multifocal Progresiva/economía , Leucoencefalopatía Multifocal Progresiva/mortalidad , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
3.
Dig Dis Sci ; 64(12): 3502-3517, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31187328

RESUMEN

BACKGROUND: Gastrointestinal (GI) motility dysfunction is the most common non-motor symptom of Parkinson's disease (PD). Studies have indicated that GI motility functions are impaired before the onset of PD. AIMS: To investigate the underlying mechanism of PD-induced GI dysmotility in MPTP (1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine)-induced animal model. METHODS: C57BL/6 mice were administered with or without a selective dopamine neurotoxin, MPTP, to induce parkinsonian symptoms. In addition to in vivo studies, in vitro experiments were also conducted in colon specimens using l-methyl-4-phenylpyridinium (MPP+), a metabolic product of MPTP. Gastric emptying, colon motility, nitrergic relaxation, and western blot experiments were performed as reported. RESULTS: MPTP-induced PD mice showed decreased expression of nuclear factor erythroid 2-related factor (Nrf2) and its target phase II genes in gastric and colon neuromuscular tissues. Decreased levels of tetrahydrobiopterin (BH4, a critical cofactor for nNOS dimerization) associated with uncoupling of nNOS in gastric and colon tissues exposed to MPTP. Impaired enteric nitrergic system led to delayed gastric emptying and slower colonic motility compared to the control mice. In vitro results in colon specimens confirm that activation of Nrf2 restored MPP+-induced suppression of alpha-synuclein, tyrosine hydroxylase (TH), Nrf2, and heme oxygenase-1. In vitro exposure to L-NAME [N(w)-nitro-L-arginine methyl ester], a NOS synthase inhibitor, reduced protein expression of TH in colon tissue homogenates. CONCLUSIONS: Loss of Nrf2/BH4/nNOS expression in PD impairs antioxidant gene expression, which deregulates NO synthesis, thereby contributing to the development of GI dysmotility and constipation. Nitric oxide appears to be important to maintain dopamine synthesis in the colon.


Asunto(s)
Motilidad Gastrointestinal/fisiología , Intoxicación por MPTP/genética , Factor 2 Relacionado con NF-E2/genética , Óxido Nítrico Sintasa de Tipo I/genética , Óxido Nítrico/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , 1-Metil-4-fenilpiridinio/farmacología , Animales , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Western Blotting , Colon/efectos de los fármacos , Colon/metabolismo , Colon/fisiopatología , Estreñimiento , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacología , Vaciamiento Gástrico/fisiología , Regulación de la Expresión Génica , Hemo-Oxigenasa 1/efectos de los fármacos , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Intoxicación por MPTP/metabolismo , Intoxicación por MPTP/fisiopatología , Masculino , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/metabolismo , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Enfermedad de Parkinson/fisiopatología , Trastornos Parkinsonianos , Tirosina 3-Monooxigenasa/efectos de los fármacos , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismo , alfa-Sinucleína/efectos de los fármacos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
4.
J Clin Virol ; 162: 105445, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37043902

RESUMEN

BACKGROUND: Human pegivirus (HPgV) is a single-stranded RNA virus​ that is closely related to hepatitis C virus (HCV)​. HPgV has also been shown to infect patients with human immunodeficiency virus (HIV). The mechanisms and disease outcomes of HPgV infections are largely unknown, although it has been implicated in both cancer and neurological diseases. There are no established therapies for HPgV. OBJECTIVES: To estimate the prevalence of HPgV in a cohort of HCV/HIV co-infected patients undergoing treatment for HCV with direct acting antivirals (DAA) and investigate the effect of DAA therapy on HPgV infection. STUDY DESIGN: RNA was extracted from plasma samples collected at time points before, during, and after DAA. HPgV RNA abundance was quantified by droplet digital PCR assays targeting the NS5A and 5'UTR domains and confirmed by RT-qPCR. Clinical, demographic and treatment data were analysed. RESULTS: HPgV RNA was detected and quantified in 26 of 100 patients' plasma (26%) before starting DAA. Patients with detectable HPgV were more likely to be male, had higher peak HIV plasma levels, and a history of injection drug use. Patients receiving sofosbuvir/ledipasvir (n = 9) displayed significantly lower HPgV levels at time of DAA completion and had lower post-DAA HPgV rebound​ levels compared to patients receiving sofosbuvir/velpatasvir (n = 11) although both regimens significantly reduced viremia directly following DAA completion. Sustained suppression of HPgV was â€‹also observed among patients (n = 2) receiving pegylated-interferon. CONCLUSIONS: HPgV RNA ​was frequently detected in HCV/HIV co-infected patients and ​was​ supressed by DAA and pegylated interferon therapies with sofosbuvir-ledipasvir showing greatest antiviral activity. These findings suggest potential treatment strategies for HPgV infections​.


Asunto(s)
Coinfección , Infecciones por VIH , Hepatitis C Crónica , Hepatitis C , Humanos , Masculino , Femenino , Hepacivirus/genética , Antivirales/farmacología , Sofosbuvir/uso terapéutico , Pegivirus/genética , VIH/genética , Viremia/tratamiento farmacológico , Coinfección/tratamiento farmacológico , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Interferones/farmacología , Interferones/uso terapéutico , ARN Viral/genética , Polietilenglicoles/uso terapéutico , Polietilenglicoles/farmacología
5.
Am J Cardiol ; 160: 117-123, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34583809

RESUMEN

The accuracy of ankle-brachial index (ABI) and toe-brachial index (TBI) in discriminating lower extremity peripheral artery disease (PAD) has not been evaluated in patients with chronic kidney disease (CKD). We measured ABI, TBI, and Doppler ultrasound in 100 predialysis patients with CKD without revascularization or amputation. Leg-specific ABI was calculated using higher systolic blood pressure (SBP) in posterior tibial or dorsalis pedis artery divided by higher brachial SBP; alternative ABI was calculated using lower SBP in posterior tibial or dorsalis pedis artery. PAD was defined as ≥50% stenosis detected by Doppler ultrasound. PAD risk classification score was calculated using cardiovascular disease risk factors. The area under the curve (AUC, 95% confidence interval [CI]) for discriminating ultrasound-diagnosed PAD was 0.78 (0.69 to 0.87) by ABI, 0.80 (0.71 to 0.89) by alternative ABI, and 0.74 (0.63 to 0.86) by TBI. Sensitivity and specificity were 25% and 97% for ABI ≤0.9, 41% and 95% for alternative ABI ≤0.9, and 45% and 93% for TBI ≤0.7, respectively. AUC (95% CI) of PAD risk classification score was 0.86 (0.78 to 0.94) with sensitivity and specificity of 95% and 60% for risk score ≥0.10, 76% and 76% for risk score ≥0.25, and 43% and 95% for risk score ≥0.55. Combining risk score with ABI, alternative ABI, and TBI increased AUC (95% CI) to 0.89 (0.82 to 0.96), 0.89 (0.80 to 0.98), and 0.87 (0.78 to 0.96), respectively. In conclusion, current ABI and TBI diagnostic criteria have high specificity but low sensitivity for classifying PAD in patients with CKD. PAD classification risk score based on cardiovascular disease risk factors improves the accuracy of PAD classification.


Asunto(s)
Índice Tobillo Braquial , Enfermedad Arterial Periférica/diagnóstico , Insuficiencia Renal Crónica/fisiopatología , Ultrasonografía Doppler , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Arteria Braquial/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/complicaciones , Insuficiencia Renal Crónica/complicaciones , Medición de Riesgo , Sensibilidad y Especificidad , Arterias Tibiales/fisiopatología , Dedos del Pie/irrigación sanguínea
6.
Age Ageing ; 39(5): 588-91, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20625184

RESUMEN

BACKGROUND: most patients with moderate cognitive impairment are unable to perform forced spirometry. It has been suggested that slow vital capacity (SVC) is easier to perform than forced vital capacity (FVC) because it requires less understanding and co-ordination. We conducted a study to determine whether that assertion is correct. METHODS: we studied 83 inpatients, mean age 83 years (range 67-95, 51 female). They had measurements made of FVC, SVC and the Mini-Mental State Examination (MMSE). The spirometry was conducted using the European Respiratory Society/American Thoracic Society standards. RESULTS: of the 83 subjects, 38 were able to do both FVC and SVC and 32 were unable to do either. The overall concordance was 84%. Twelve were able to do SVC but not FVC (eight due to excessive cough, two due to weakness and two had an MMSE < 24 with poor co-ordination). An inability to do neither FVC nor SVC was predicted by an MMSE < 24/30 (P < 0.0001) with a sensitivity of 88% and specificity of 67%. CONCLUSION: SVC is not a usable substitute for FVC for elderly patients with cognitive impairment but is of some utility for those who tend to cough. An MMSE < 24/30 is predictive of inability to perform FVC and SVC.


Asunto(s)
Envejecimiento/fisiología , Trastornos del Conocimiento/fisiopatología , Enfermedades Pulmonares/diagnóstico , Espirometría/métodos , Capacidad Vital/fisiología , Anciano , Anciano de 80 o más Años , Cognición/fisiología , Tos/etiología , Femenino , Humanos , Enfermedades Pulmonares/fisiopatología , Masculino , Cooperación del Paciente , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Espirometría/efectos adversos
7.
Clin J Am Soc Nephrol ; 15(11): 1566-1575, 2020 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-33023894

RESUMEN

BACKGROUND AND OBJECTIVES: Endothelial dysfunction is common among patients with CKD. We tested the efficacy and safety of combination treatment with sodium nitrite and isoquercetin on biomarkers of endothelial dysfunction in patients with CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This randomized, double-blind, placebo-controlled phase 2 pilot trial enrolled 70 patients with predialysis CKD. Thirty-five were randomly assigned to combination treatment with sodium nitrite (40 mg twice daily) and isoquercetin (225 mg once daily) for 12 weeks, and 35 were randomly assigned to placebo. The primary outcome was mean change in flow-mediated vasodilation over the 12-week intervention. Secondary and safety outcomes included biomarkers of endothelial dysfunction, inflammation, and oxidative stress as well as kidney function, methemoglobin, and adverse events. Intention-to-treat analysis was conducted. RESULTS: Baseline characteristics, including age, sex, race, cigarette smoking, history of hypertension and diabetes, use of renin-angiotensin system blockers, BP, fasting glucose, lipid profile, kidney function, urine albumin-creatinine ratio, and endothelial biomarkers, were comparable between groups. Over the 12-week intervention, flow-mediated vasodilation increased 1.1% (95% confidence interval, -0.1 to 2.3) in the treatment group and 0.3% (95% confidence interval, -0.9 to 1.5) in the placebo group, and net change was 0.8% (95% confidence interval, -0.9 to 2.5). In addition, changes in biomarkers of endothelial dysfunction (vascular adhesion molecule-1, intercellular adhesion molecule-1, E-selectin, vWf, endostatin, and asymmetric dimethylarginine), inflammation (TNF-α, IL-6, C-reactive protein, IL-1 receptor antagonist, and monocyte chemoattractant protein-1), and oxidative stress (oxidized LDL and nitrotyrosines) were not significantly different between the two groups. Furthermore, changes in eGFR, urine albumin-creatinine ratio, methemoglobin, and adverse events were not significantly different between groups. CONCLUSIONS: This randomized phase 2 pilot trial suggests that combination treatment with sodium nitrite and isoquercetin did not significantly improve flow-mediated vasodilation or other endothelial function biomarkers but also did not increase adverse events compared with placebo among patients with CKD. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Nitrite, Isoquercetin, and Endothelial Dysfunction (NICE), NCT02552888.


Asunto(s)
Endotelio/efectos de los fármacos , Quercetina/análogos & derivados , Insuficiencia Renal Crónica/tratamiento farmacológico , Nitrito de Sodio/farmacología , Vasodilatación/efectos de los fármacos , Anciano , Amina Oxidasa (conteniendo Cobre)/sangre , Antioxidantes/farmacología , Arginina/análogos & derivados , Arginina/sangre , Biomarcadores/sangre , Moléculas de Adhesión Celular/sangre , Quimioterapia Combinada , Selectina E/sangre , Endostatinas/sangre , Endotelio/fisiopatología , Femenino , Tasa de Filtración Glomerular , Humanos , Inflamación/sangre , Molécula 1 de Adhesión Intercelular/sangre , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Proyectos Piloto , Quercetina/efectos adversos , Quercetina/farmacología , Insuficiencia Renal Crónica/fisiopatología , Nitrito de Sodio/efectos adversos , Factor de von Willebrand/metabolismo
8.
J Cell Biol ; 138(2): 331-6, 1997 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-9230075

RESUMEN

Myoblast fusion is essential to muscle tissue development yet remains poorly understood. N-cadherin, like other cell surface adhesion molecules, has been implicated by others in muscle formation based on its pattern of expression and on inhibition of myoblast aggregation and fusion by antibodies or peptide mimics. Mice rendered homozygous null for N-cadherin revealed the general importance of the molecule in early development, but did not test a role in skeletal myogenesis, since the embryos died before muscle formation. To test genetically the proposed role of N-cadherin in myoblast fusion, we successfully obtained N-cadherin null primary myoblasts in culture. Fusion of myoblasts expressing or lacking N-cadherin was found to be equivalent, both in vitro by intracistronic complementation of lacZ and in vivo by injection into the muscles of adult mice. An essential role for N-cadherin in mediating the effects of basic fibroblast growth factor was also excluded. These methods for obtaining genetically homozygous null somatic cells from adult tissues should have broad applications. Here, they demonstrate clearly that the putative fusion molecule, N-cadherin, is not essential for myoblast fusion.


Asunto(s)
Cadherinas/fisiología , Fusión Celular/fisiología , Músculo Esquelético/citología , Animales , Cadherinas/genética , Células Cultivadas , Células Clonales , Factor 2 de Crecimiento de Fibroblastos/fisiología , Homocigoto , Ratones , Ratones Desnudos , Fibras Musculares Esqueléticas/citología , Mutación
9.
J Clin Virol ; 104: 23-28, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29704735

RESUMEN

BACKGROUND: False-reactivity in HIV-negative specimens has been detected in HIV fourth-generation antigen/antibody or 'combo' assays which are able to detect both anti-HIV-1/HIV-2 antibodies and HIV-1 antigen. OBJECTIVES: We sought to characterize these specimens and determine the effect of heterophilic interference. STUDY DESIGN: Specimens previously testing as false-reactive on the Abbott ARCHITECT HIV Ag/Ab combo assay and re-tested on a different (Siemens ADVIA Centaur HIV Ag/Ab) assay. A subset of these specimens were also pre-treated with heterophilic blocking agents and re-tested on the Abbott assay. RESULTS: Here we report that 95% (252/264) of clinical specimens that were repeatedly reactive on the Abbott ARCHITECT HIV Ag/Ab combo assay (S/Co range, 0.94-678) were negative when re-tested on a different fourth generation HIV combo assay (Siemens ADVIA Centaur HIV Ag/Ab). All 264 samples were subsequently confirmed to be HIV negative. On a small subset (57) of specimens with available volume, pre-treatment with two different reagents (HBT; Heterophilic Blocking Tube, NABT; Non-Specific Blocking Tube) designed to block heterophilic antibody interference either eliminated (HBT) or reduced (NABT) the false reactivity when re-tested on the ARCHITECT HIV Ag/Ab combo assay. CONCLUSIONS: Our results suggest that the Abbott ARCHITECT HIV Ag/Ab combo assay can be prone to heterophilic antibody interference.


Asunto(s)
Reacciones Falso Positivas , Anticuerpos Anti-VIH/sangre , Antígenos VIH/sangre , Infecciones por VIH/diagnóstico , Inmunoensayo/métodos , Anticuerpos Heterófilos/sangre , VIH-1/inmunología , VIH-2/inmunología , Humanos
10.
Infect Genet Evol ; 52: 100-105, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28427935

RESUMEN

Molecular epidemiology has become a key tool for tracking infectious disease epidemics. Here, the spread of the most prevalent HIV-1 subtypes in Northern Alberta, Canada, was characterized with a Bayesian phylogenetic approach using 1146 HIV-1 pol sequences collected between 2007 and 2013 for routine clinical management purposes. Available patient metadata were qualitatively interpreted and correlated with onwards transmission using Fisher exact tests and logistic regression. Most infections were from subtypes A (n=36), B (n=815) and C (n=211). Africa is the dominant origin location for subtypes A and C while the subtype B epidemic was seeded from the USA and Middle America and, from the early 1990s onwards, mostly by interprovincial spread. Subtypes A (77.8%) and C (74.0%) were usually heterosexually transmitted and circulate predominantly among Blacks (61.1% and 85% respectively). Subtype B was mostly found among Caucasians (48.6%) and First Nations (36.8%), and its modes of transmission were stratified by ethnic origin. Compared to subtypes A (5.6%) and C (3.8-10.0%), a larger portion of subtype B patients were found within putative provincial transmission networks (20.3-29.5%), and this almost doubled when focusing on nationwide transmission clusters (37.9-57.5%). No clear association between cluster membership and particular patient characteristics was found. This study reveals complex and multi-faceted transmission dynamics of the HIV-1 epidemic in this otherwise low HIV prevalence population in Northern Alberta, Canada. These findings can aid public health planning.


Asunto(s)
Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , VIH-1/clasificación , VIH-1/genética , Adolescente , Adulto , África , Anciano , Alberta/epidemiología , Teorema de Bayes , América Central , Femenino , Infecciones por VIH/etnología , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Filogeografía , Salud Pública , Estados Unidos , Adulto Joven , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
11.
J Hosp Infect ; 93(2): 141-4, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27105751

RESUMEN

In many parts of the world, carbapenemase-producing organisms (CPOs) are endemic. The transfer of medical patients from such countries to the UK requires us to have control systems in place to avoid onward transmission. This report describes the experience of a regional burns centre challenged by its first four cases of CPO in two separate incidents. Key learning from our experience was the importance of CPOs being considered in empirical antibiotics for any patient from an endemic area. Using contact plates, we demonstrated high bacterial counts after cleaning and we describe a terminal cleaning strategy along with the importance of continuing staff engagement and education.


Asunto(s)
Proteínas Bacterianas/metabolismo , Quemaduras/complicaciones , Infección Hospitalaria/prevención & control , Transmisión de Enfermedad Infecciosa/prevención & control , Bacterias Gramnegativas/enzimología , Infecciones por Bacterias Gramnegativas/prevención & control , Control de Infecciones/métodos , beta-Lactamasas/metabolismo , Unidades de Quemados , Infección Hospitalaria/diagnóstico , Infección Hospitalaria/microbiología , Infección Hospitalaria/transmisión , Microbiología Ambiental , Bacterias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/transmisión , Humanos , Reino Unido
13.
Cancer Treat Rev ; 19 Suppl C: 27-33, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8221713

RESUMEN

To evaluate the activity of long-term, single-agent oral etoposide against advanced breast cancer, this study employed etoposide 50 mg/day and 100 mg/day (given over 14 days) in previously treated and chemotherapy-naive patients with histologically confirmed, recurrent or metastatic breast cancer. Of 38 patients, 24 had had chemotherapy, 34 had prior radiotherapy, and 31 had received hormone therapy. Etoposide courses in both treatment groups were repeated every 4 weeks for at least two courses; delays were instituted when patients' total leukocyte nadir fell to or below 3.0 x 10(9)/l. Dose reductions were made in the 100-mg group (to 50 mg/day) if World Health Organization leukopenia grade 3 or higher was present. Plasma pharmacokinetic profiles were measured in selected patients to assess inter- and intrapatient variability in etoposide's oral bioavailability. No complete responses were achieved among the 36 patients evaluable for response, but eight patients had a partial response. Responses were more frequent at the 100-mg dose and in previously untreated patients (seven of eight partial responders had not had previous chemotherapy). Median duration of response was 16 weeks (range, 7 to 46). Myelosuppression (variable and unpredictable) and alopecia (universal) were the notable toxicities. Pharmacokinetic analyses of oral bioavailability revealed significant interpatient variability, but much less intrapatient variability when successive etoposide courses in individual patients were evaluated. Despite the relatively small number of patients in this study, the responses achieved by previously untreated patients suggest etoposide's value against breast cancer. Further trials should use pharmacokinetic studies to assess bioavailability as well as to help define 'target' etoposide doses, based on plasma etoposide levels, during treatment.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Etopósido/uso terapéutico , Administración Oral , Adulto , Anciano , Etopósido/administración & dosificación , Etopósido/efectos adversos , Etopósido/farmacocinética , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia
14.
Mol Neurobiol ; 9(1-3): 149-61, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7888091

RESUMEN

The major symptoms of Parkinson's disease (PD) are tremors, hypokinesia, rigidity, and abnormal posture, caused by degeneration of dopamine (DA) neurons in the substantia nigra (SN) and deficiency of DA in the neostriatal dopaminergic terminals. Norepinephrine, serotonin, and melanin pigments are also decreased and cholinergic activity is increased. The cause of PD is unknown. Increased methylation reactions may play a role in the etiology of PD, because it has been observed recently that the CNS administration of S-adenosyl-L-methionine (SAM), the methyl donor, caused tremors, hypokinesia, and rigidity; symptoms that resemble those that occur in PD. Furthermore, many of the biochemical changes seen in PD resemble changes that could occur if SAM-dependent methylation reactions are increased in the brain, and interestingly, L-DOPA, the most effective drug used to treat PD, reacts avidly with SAM. So methylation may be important in PD; an idea that is of particular interest because methylation reactions increase in aging, the symptoms of PD are strikingly similar to the neurological and functional changes seen in advanced aging, and PD is age-related. For methylation to be regarded as important in PD it means that, along with its biochemical reactions and behavioral effects, increased methylation should also cause specific neuronal degeneration. To know this, the effects of an increase in methylation in the brain were studied by injecting SAM into the lateral ventricle of rats. The injection of SAM caused neuronal degeneration, noted by a loss of neurons, gliosis, and increased silver reactive fibers in the SN. The degeneration was accompanied with a decrease in SN tyrosine hydroxylase (TH) immunoreactivity, and degeneration of TH-containing fibers. At the injection site in the lateral ventricle it appears that SAM caused a weakening or dissolution of the intercellular substances; observed as a disruption of the ependymal cell layer and the adjacent caudate tissues. SAM may also cause brain atrophy; evidenced by the dilation of the cerebral ventricle. Most of the SAM-induced anatomical changes that were observed in the rat model are similar to the changes that occur in PD, which further support a role of SAM-dependent increased methylation in PD.


Asunto(s)
Química Encefálica , Degeneración Nerviosa/fisiología , Enfermedad de Parkinson/metabolismo , S-Adenosilmetionina/metabolismo , Sustancia Negra/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Animales , Masculino , Metilación , Enfermedad de Parkinson/patología , Ratas , Ratas Sprague-Dawley , Sustancia Negra/patología
15.
Clin Exp Metastasis ; 10(1): 3-11, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1346375

RESUMEN

Metastatic prostate cancer is well known to respond to hormonal manipulations, but once progression occurs new treatment modalities are required. Specific and systemic antitumour therapy is preferable to local treatments such as radiotherapy in such patients. The finding that somatostatin analogue, BIM 23014, inhibits prostatic tumour growth in animal models is of great interest. We treated 25 poor risk patients with progressive metastatic prostate cancer. Sixteen had also failed to respond to 'total androgen blockade'. Two patients have achieved a partial remission, one of which is maintained at over 30 months, and three had stable disease for over 6 months. Side effects have consisted of mild diarrhoea and abdominal cramp in the first few days of treatment in a minority of the patients. These results are encouraging and further randomized studies are in progress.


Asunto(s)
Antineoplásicos/uso terapéutico , Oligopéptidos/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Somatostatina/análogos & derivados , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/secundario , Diarrea/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Péptidos Cíclicos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/mortalidad , Cintigrafía , Somatostatina/uso terapéutico
16.
Eur J Cancer ; 31A(13-14): 2409-11, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8652278

RESUMEN

Etoposide phosphate is a water-soluble prodrug of etoposide. A phase I and pharmacokinetic study has been performed over the dose range 25-110 mg/m2/day for 5 days (etoposide equivalent doses). The maximum tolerated dose (MTD) was 110 mg/m2/day for 5 days every 3 weeks and the dose-limiting toxicity was neutropenia. Other toxicities were mild, with the exception of 2 patients who displayed significant hypersensitivity reactions. The etoposide phosphate:etoposide area under the plasma concentration versus time curve (AUC) ratio was < 1% and the pharmacokinetic parameters for etoposide were within previously reported ranges. Pharmacodynamic analyses demonstrated that etoposide AUC and baseline white blood cell count were significant determinants of leucopenia (model r2 = 0.51).


Asunto(s)
Antineoplásicos/administración & dosificación , Etopósido/análogos & derivados , Neoplasias/tratamiento farmacológico , Compuestos Organofosforados/administración & dosificación , Profármacos/administración & dosificación , Adulto , Anciano , Antineoplásicos/farmacocinética , Esquema de Medicación , Resistencia a Antineoplásicos , Etopósido/administración & dosificación , Etopósido/farmacocinética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organofosforados/farmacocinética , Neoplasias Ováricas/tratamiento farmacológico , Profármacos/farmacocinética
17.
Neuroscience ; 19(2): 523-33, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2430231

RESUMEN

Substance P-immunoreactivity and specific substance P binding sites are present in the spinal cord. Receptor autoradiography showed the discrete localization of substance P binding sites in both sensory and motor regions of the spinal cord and functional studies suggested an important role for substance P receptor activation in autonomic outflow, nociception, respiration and somatic motor function. In the current studies, we investigated the cellular localization of substance P binding sites in rat spinal cord using light microscopic autoradiography combined with several lesioning techniques. Unilateral injections of the suicide transport agent, ricin, into the superior cervical ganglion reduced substance P binding and cholinesterase-stained preganglionic sympathetic neurons in the intermediolateral cell column. However, unilateral electrolytic lesions of ventral medullary substance P neurons which project to the intermediolateral cell column did not alter the density of substance P binding in the intermediolateral cell column. Likewise, 6-hydroxydopamine and 5,7-dihydroxytryptamine, which destroy noradrenergic and serotonergic nerve terminals, did not reduce the substance P binding in the intermediolateral cell column. It appears, therefore, that the substance P binding sites are located postsynaptically on preganglionic sympathetic neurons rather than presynaptically on substance P-immunoreactive processes (i.e. as autoreceptors) or on monoamine nerve terminals. Unilateral injections of ricin into the phrenic nerve resulted in the unilateral destruction of phrenic motor neurons in the cervical spinal cord and caused a marked reduction in the substance P binding in the nucleus. Likewise, sciatic nerve injections of ricin caused a loss of associated motor neurons in the lateral portion of the ventral horn of the lumbar spinal cord and a reduction in the substance P binding. Sciatic nerve injections of ricin also destroyed afferent nerves of the associated dorsal root ganglia and increased the density of substance P binding in the dorsal horn. Capsaicin, which destroys small diameter primary sensory neurons, similarly increased the substance P binding in the dorsal horn. These studies show that the cellular localization of substance P binding sites can be determined by analysis of changes in substance P binding to discrete regions of spinal cord after selective lesions of specific groups of neurons. The data show the presence of substance P binding sites on preganglionic sympathetic neurons in the intermediolateral cell column and on somatic motor neurons in the ventral horn, including the phrenic motor nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Receptores de Neurotransmisores/metabolismo , Médula Espinal/metabolismo , Sustancia P/metabolismo , Animales , Fibras Autónomas Preganglionares/metabolismo , Autorradiografía , Masculino , Bulbo Raquídeo/fisiología , Neuronas Motoras/metabolismo , Nervio Frénico/metabolismo , Ratas , Ratas Endogámicas , Receptores de Neuroquinina-1 , Sistema Nervioso Simpático/metabolismo
18.
Biotechniques ; 21(2): 260-2, 264, 266, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8862811

RESUMEN

We have developed a spectrophotometric assay for cell number in suspensions of tissue culture cells. For each cell type tested, absorbance between 650 and 800 nm is linearly dependent upon cell density over a 50-fold range and is independent of the color or composition of the medium in which cells are suspended. A standard curve of absorbance vs. cell density is used to estimate cell number with accuracy and reproducibility superior to hemacytometer counting and with speed and ease surpassing use of a Coulter counter. Less than 5000 cells are needed for this quantitation. The same cells that are counted can be maintained live in culture after the reading is taken, thus allowing the growth of cells to be measured within individual cultures over time. The assay should be readily extended to assays of cell number directly within microplate culture wells. The spectrophotometric assay described here is of significant use in all experiments requiring rapid, accurate measurements of cell number, including determinations of cell doubling time and equal plating of parallel cultures.


Asunto(s)
Recuento de Células/métodos , Espectrofotometría/métodos , Animales , Células Cultivadas , Medios de Cultivo , Ratones
19.
Drugs ; 37(6): 926-38, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2667939

RESUMEN

The drug treatment of acute leukaemia has changed considerably over the past years, offering the possibility of remission and, in some cases, cure. The broad outline of treatment schedules, the drugs in current use and newer approaches to therapy are discussed. Bone marrow transplantation is described in brief, as well as the role of support therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Leucemia/tratamiento farmacológico , Enfermedad Aguda , Humanos
20.
J Clin Pathol ; 19(3): 238-40, 1966 May.
Artículo en Inglés | MEDLINE | ID: mdl-5937608

RESUMEN

The blood and urinary fibrinolytic activities were simultaneously estimated in 14 ;normal' patients under basal conditions on successive days. No direct correlation between the fibrinolytic activities in the blood and urine was demonstrated. The origin of urokinase is discussed.


Asunto(s)
Sangre , Fibrinólisis , Fibrinolíticos , Orina , Técnicas In Vitro
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