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1.
Clin Infect Dis ; 76(1): 39-47, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36097726

RESUMO

BACKGROUND: Treat-All guidelines recommend initiation of antiretroviral therapy (ART) for all people with HIV (PWH) on the day of diagnosis when possible, yet uncertainty exists about the impact of same-day ART initiation on subsequent care engagement. We examined the association of same-day ART initiation with loss to follow-up and viral suppression among patients in 11 sub-Saharan African countries. METHODS: We included ART-naive adult PWH from sites participating in the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium who enrolled in care after Treat-All implementation and prior to January 2019. We used multivariable Cox regression to estimate the association between same-day ART initiation and loss to follow-up and Poisson regression to estimate the association between same-day ART initiation and 6-month viral suppression. RESULTS: Among 29 017 patients from 63 sites, 18 584 (64.0%) initiated ART on the day of enrollment. Same-day ART initiation was less likely among those with advanced HIV disease versus early-stage disease. Loss to follow-up was significantly lower among those initiating ART ≥1 day of enrollment, compared with same-day ART initiators (20.6% vs 27.7%; adjusted hazard ratio: .66; 95% CI .57-.76). No difference in viral suppression was observed by time to ART initiation (adjusted rate ratio: 1.00; 95% CI: .98-1.02). CONCLUSIONS: Patients initiating ART on the day of enrollment were more frequently lost to follow-up than those initiating later but were equally likely to be virally suppressed. Our findings support recent World Health Organization recommendations for providing tailored counseling and support to patients who accept an offer of same-day ART.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Humanos , HIV , Seguimentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Fármacos Anti-HIV/uso terapêutico , África Subsaariana/epidemiologia
2.
Lifetime Data Anal ; 26(4): 659-684, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31982977

RESUMO

The cause of failure in cohort studies that involve competing risks is frequently incompletely observed. To address this, several methods have been proposed for the semiparametric proportional cause-specific hazards model under a missing at random assumption. However, these proposals provide inference for the regression coefficients only, and do not consider the infinite dimensional parameters, such as the covariate-specific cumulative incidence function. Nevertheless, the latter quantity is essential for risk prediction in modern medicine. In this paper we propose a unified framework for inference about both the regression coefficients of the proportional cause-specific hazards model and the covariate-specific cumulative incidence functions under missing at random cause of failure. Our approach is based on a novel computationally efficient maximum pseudo-partial-likelihood estimation method for the semiparametric proportional cause-specific hazards model. Using modern empirical process theory we derive the asymptotic properties of the proposed estimators for the regression coefficients and the covariate-specific cumulative incidence functions, and provide methodology for constructing simultaneous confidence bands for the latter. Simulation studies show that our estimators perform well even in the presence of a large fraction of missing cause of failures, and that the regression coefficient estimator can be substantially more efficient compared to the previously proposed augmented inverse probability weighting estimator. The method is applied using data from an HIV cohort study and a bladder cancer clinical trial.


Assuntos
Funções Verossimilhança , Modelos de Riscos Proporcionais , Medição de Risco/métodos , Estudos de Coortes , Simulação por Computador , Humanos
3.
BMC Bioinformatics ; 19(1): 244, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29940833

RESUMO

BACKGROUND: The Top Scoring Pair (TSP) classifier, based on the concept of relative ranking reversals in the expressions of pairs of genes, has been proposed as a simple, accurate, and easily interpretable decision rule for classification and class prediction of gene expression profiles. The idea that differences in gene expression ranking are associated with presence or absence of disease is compelling and has strong biological plausibility. Nevertheless, the TSP formulation ignores significant available information which can improve classification accuracy and is vulnerable to selecting genes which do not have differential expression in the two conditions ("pivot" genes). RESULTS: We introduce the AUCTSP classifier as an alternative rank-based estimator of the magnitude of the ranking reversals involved in the original TSP. The proposed estimator is based on the Area Under the Receiver Operating Characteristic (ROC) Curve (AUC) and as such, takes into account the separation of the entire distribution of gene expression levels in gene pairs under the conditions considered, as opposed to comparing gene rankings within individual subjects as in the original TSP formulation. Through extensive simulations and case studies involving classification in ovarian, leukemia, colon, breast and prostate cancers and diffuse large b-cell lymphoma, we show the superiority of the proposed approach in terms of improving classification accuracy, avoiding overfitting and being less prone to selecting non-informative (pivot) genes. CONCLUSIONS: The proposed AUCTSP is a simple yet reliable and robust rank-based classifier for gene expression classification. While the AUCTSP works by the same principle as TSP, its ability to determine the top scoring gene pair based on the relative rankings of two marker genes across all subjects as opposed to each individual subject results in significant performance gains in classification accuracy. In addition, the proposed method tends to avoid selection of non-informative (pivot) genes as members of the top-scoring pair.


Assuntos
Biomarcadores/química , Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Algoritmos , Humanos
4.
Clin Infect Dis ; 67(1): 65-72, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29346632

RESUMO

Background: Progressive multifocal leukoencephalopathy (PML) is a severe demyelinating disease caused by the polyomavirus JC (John Cunningham; JCV) that affects patients with impaired immune systems. While JCV-DNA detection in cerebrospinal fluid (CSF) is diagnostic of PML, the clinical significance of plasma JCV-DNA is uncertain. Methods: We retrospectively analyzed plasma samples from PML patients that were drawn close to disease onset and from controls without PML. In PML patients, we compared plasma JCV-DNA detection and levels to clinical and laboratory parameters, and patient survival. Results: JCV-DNA was detected in plasma of 49/103 (48%) patients with PML (20/24, 83%, human immunodeficiency virus [HIV] negative; 29/79, 37%, HIV-positive) and of 4/144 (3%) controls without PML (0/95 HIV-negative; 4/49, 8%, HIV-positive), yielding a diagnostic sensitivity and specificity of 48% and 97% (83% and 100% in HIV-negative; 37% and 92% in HIV-positive), respectively. Among 16 PML patients with undetectable CSF JCV-DNA, 4 (25%) had detectable plasma JCV-DNA. Plasma JCV-DNA levels were independently associated with CSF levels (P < .0001) and previous corticosteroid treatment (P = .012). Higher plasma JCV-DNA levels were associated with disease progression in HIV-negative patients (P = .005); in HIV-positive patients, there was an increased risk of progression only in those treated with combination antiretroviral therapy (cART; P < .0001). Conclusions: Testing JCV-DNA in plasma might complement PML diagnosis, especially when CSF is unavailable or JCV-DNA not detectable in CSF. In addition, JCV-DNA plasma levels could be useful as a marker of disease progression in both HIV-negative and cART-treated, HIV-positive PML patients.


Assuntos
DNA Viral/sangue , Vírus JC/isolamento & purificação , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Adulto , Idoso , Antirretrovirais/uso terapêutico , Técnicas de Laboratório Clínico , Progressão da Doença , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/virologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
5.
BMC Cancer ; 17(1): 611, 2017 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-28865422

RESUMO

BACKGROUND: Throughout most of sub-Saharan Africa (and, indeed, most resource-limited areas), lack of death registries prohibits linkage of cancer diagnoses and precludes the most expeditious approach to determining cancer survival. Instead, estimation of cancer survival often uses clinical records, which have some mortality data but are replete with patients who are lost to follow-up (LTFU), some of which may be caused by undocumented death. The end result is that accurate estimation of cancer survival is rarely performed. A prominent example of a common cancer in Africa for which survival data are needed but for which frequent LTFU has precluded accurate estimation is Kaposi sarcoma (KS). METHODS: Using electronic records, we identified all newly diagnosed KS among HIV-infected adults at 33 primary care clinics in Kenya, Uganda, Nigeria, and Malawi from 2009 to 2012. We determined those patients who were apparently LTFU, defined as absent from clinic for ≥90 days at database closure and unknown to be dead or transferred. Using standardized protocols which included manual chart review, telephone calls, and physical tracking in the community, we attempted to update vital status amongst patients who were LTFU. RESULTS: We identified 1222 patients with KS, of whom 440 were LTFU according to electronic records. Manual chart review revealed that 18 (4.1%) were classified as LFTU due to clerical error, leaving 422 as truly LTFU. Of these 422, we updated vital status in 78%; manual chart review was responsible for updating in 5.7%, telephone calls in 26%, and physical tracking in 46%. Among 378 patients who consented at clinic enrollment to be tracked if they became LTFU and who had sufficient geographic contact/locator information, we updated vital status in 88%. Duration of LTFU was not associated with success of tracking, but tracking success was better in Kenya than the other sites. CONCLUSION: It is feasible to update vital status in a large fraction of patients with HIV-associated KS in sub-Saharan Africa who have become LTFU from clinical care. This finding likely applies to other cancers as well. Updating vital status amongst lost patients paves the way towards accurate determination of cancer survival.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Epidemias , Infecções por HIV/epidemiologia , Sarcoma de Kaposi/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Infecções Oportunistas Relacionadas com a AIDS/fisiopatologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adulto , África Subsaariana/epidemiologia , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/complicações , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , Humanos , Perda de Seguimento , Masculino , Sarcoma de Kaposi/mortalidade , Sarcoma de Kaposi/fisiopatologia , Sarcoma de Kaposi/virologia
6.
PLoS One ; 11(8): e0159994, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27509182

RESUMO

Losses to follow-up (LTFU) remain an important programmatic challenge. While numerous patient-level factors have been associated with LTFU, less is known about facility-level factors. Data from the East African International epidemiologic Databases to Evaluate AIDS (EA-IeDEA) Consortium was used to identify facility-level factors associated with LTFU in Kenya, Tanzania and Uganda. Patients were defined as LTFU if they had no visit within 12 months of the study endpoint for pre-ART patients or 6 months for patients on ART. Adjusting for patient factors, shared frailty proportional hazard models were used to identify the facility-level factors associated with LTFU for the pre- and post-ART periods. Data from 77,362 patients and 29 facilities were analyzed. Median age at enrolment was 36.0 years (Interquartile Range: 30.1, 43.1), 63.9% were women and 58.3% initiated ART. Rates (95% Confidence Interval) of LTFU were 25.1 (24.7-25.6) and 16.7 (16.3-17.2) per 100 person-years in the pre-ART and post-ART periods, respectively. Facility-level factors associated with increased LTFU included secondary-level care, HIV RNA PCR turnaround time >14 days, and no onsite availability of CD4 testing. Increased LTFU was also observed when no nutritional supplements were provided (pre-ART only), when TB patients were treated within the HIV program (pre-ART only), and when the facility was open ≤4 mornings per week (ART only). Our findings suggest that facility-based strategies such as point of care laboratory testing and separate clinic spaces for TB patients may improve retention.


Assuntos
Atenção à Saúde/normas , Infecções por HIV/terapia , Instalações de Saúde/estatística & dados numéricos , Instalações de Saúde/normas , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Bases de Dados Factuais , Atenção à Saúde/estatística & dados numéricos , Feminino , HIV/genética , HIV/isolamento & purificação , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Infecções por HIV/virologia , Humanos , Estimativa de Kaplan-Meier , Quênia , Perda de Seguimento , Masculino , Modelos de Riscos Proporcionais , RNA Viral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tanzânia , Uganda
7.
PLoS One ; 9(12): e116081, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25541953

RESUMO

The character of central nervous system (CNS) HIV infection and its effects on neuronal integrity vary with evolving systemic infection. Using a cross-sectional design and archived samples, we compared concentrations of cerebrospinal fluid (CSF) neuronal biomarkers in 143 samples from 8 HIV-infected subject groups representing a spectrum of untreated systemic HIV progression and viral suppression: primary infection; four groups of chronic HIV infection neuroasymptomatic (NA) subjects defined by blood CD4+ T cells of >350, 200-349, 50-199, and <50 cells/µL; HAD; treatment-induced viral suppression; and 'elite' controllers. Samples from 20 HIV-uninfected controls were also examined. The neuronal biomarkers included neurofilament light chain protein (NFL), total and phosphorylated tau (t-tau, p-tau), soluble amyloid precursor proteins alpha and beta (sAPPα, sAPPß) and amyloid beta (Aß) fragments 1-42, 1-40 and 1-38. Comparison of the biomarker changes showed a hierarchy of sensitivity in detection and suggested evolving mechanisms with progressive injury. NFL was the most sensitive neuronal biomarker. Its CSF concentration exceeded age-adjusted norms in all HAD patients, 75% of NA CD4<50, 40% of NA CD4 50-199, and 42% of primary infection, indicating common neuronal injury with untreated systemic HIV disease progression as well as transiently during early infection. By contrast, only 75% of HAD subjects had abnormal CSF t-tau levels, and there were no significant differences in t-tau levels among the remaining groups. sAPPα and ß were also abnormal (decreased) in HAD, showed less marked change than NFL with CD4 decline in the absence of HAD, and were not decreased in PHI. The CSF Aß peptides and p-tau concentrations did not differ among the groups, distinguishing the HIV CNS injury profile from Alzheimer's disease. These CSF biomarkers can serve as useful tools in selected research and clinical settings for patient classification, pathogenetic analysis, diagnosis and management.


Assuntos
Infecções por HIV/líquido cefalorraquidiano , Doenças do Sistema Nervoso/líquido cefalorraquidiano , Adulto , Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Precursor de Proteína beta-Amiloide/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Estudos Transversais , Feminino , HIV/isolamento & purificação , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/complicações , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fosforilação , Proteínas tau/líquido cefalorraquidiano
8.
Clin Genitourin Cancer ; 12(1): 33-40.e4, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24126237

RESUMO

BACKGROUND: Elevated markers of bone turnover are prognostic for shorter survival in castration-resistant prostate cancer. We aimed to determine the prognostic value of bone turnover markers in metastatic hormone-sensitive prostate cancer. PATIENTS AND METHODS: Markers of bone turnover (urine deoxypyridinoline [DPD] and N-telopeptide, serum bone alkaline phosphatase (AP), and osteocalcin [OC]) from baseline and after 6 months of study were assessed in men enrolled in a prospective metastatic prostate cancer trial with androgen deprivation therapy (ADT) with or without risedronate (ClinicalTrials.gov, NCT00216060). RESULTS: Serum samples were collected from 63 patients with bone involvement and a median follow-up of 39.7 months. A multivariate model using Cox regression-which included prostate-specific antigen (PSA) nadir, bisphosphonate treatment, and extent of metastases-showed that suppression of bone turnover markers after 6 months of therapy compared with baseline was significantly associated with longer skeletal-related event (SRE)-free survival. ADT without bisphosphonate therapy was also associated with a decline in markers of bone turnover, presumably resulting from direct anticancer activity. Elevated baseline bone turnover markers were not prognostic. CONCLUSION: Failure to suppress bone turnover while receiving ADT, even when otherwise responding to therapy, may identify patients with hormone-sensitive metastatic prostate cancer who are destined for a shorter time to SREs and progression.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea/efeitos dos fármacos , Metástase Neoplásica/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Idoso , Fosfatase Alcalina/sangue , Aminoácidos/urina , Anticorpos Monoclonais Humanizados/uso terapêutico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Denosumab , Difosfonatos/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Humanos , Imidazóis/uso terapêutico , Masculino , Pessoa de Meia-Idade , Orquiectomia , Osteocalcina/sangue , Pamidronato , Prognóstico , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Ácido Zoledrônico
9.
PLoS Med ; 8(10): e1001111, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22039357

RESUMO

BACKGROUND: Although patient attrition is recognized as a threat to the long-term success of antiretroviral therapy programs worldwide, there is no universal definition for classifying patients as lost to follow-up (LTFU). We analyzed data from health facilities across Africa, Asia, and Latin America to empirically determine a standard LTFU definition. METHODS AND FINDINGS: At a set "status classification" date, patients were categorized as either "active" or "LTFU" according to different intervals from time of last clinic encounter. For each threshold, we looked forward 365 d to assess the performance and accuracy of this initial classification. The best-performing definition for LTFU had the lowest proportion of patients misclassified as active or LTFU. Observational data from 111 health facilities-representing 180,718 patients from 19 countries-were included in this study. In the primary analysis, for which data from all facilities were pooled, an interval of 180 d (95% confidence interval [CI]: 173-181 d) since last patient encounter resulted in the fewest misclassifications (7.7%, 95% CI: 7.6%-7.8%). A secondary analysis that gave equal weight to cohorts and to regions generated a similar result (175 d); however, an alternate approach that used inverse weighting for cohorts based on variance and equal weighting for regions produced a slightly lower summary measure (150 d). When examined at the facility level, the best-performing definition varied from 58 to 383 d (mean=150 d), but when a standard definition of 180 d was applied to each facility, only slight increases in misclassification (mean=1.2%, 95% CI: 1.0%-1.5%) were observed. Using this definition, the proportion of patients classified as LTFU by facility ranged from 3.1% to 45.1% (mean=19.9%, 95% CI: 19.1%-21.7%). CONCLUSIONS: Based on this evaluation, we recommend the adoption of ≥180 d since the last clinic visit as a standard LTFU definition. Such standardization is an important step to understanding the reasons that underlie patient attrition and establishing more reliable and comparable program evaluation worldwide. Please see later in the article for the Editors' Summary.


Assuntos
Terapia Antirretroviral de Alta Atividade/estatística & dados numéricos , Atenção à Saúde/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , HIV , Perda de Seguimento , Terminologia como Assunto , Adolescente , Adulto , África , Ásia , Estudos de Coortes , Seguimentos , Humanos , América Latina , Cooperação do Paciente
10.
J Am Coll Surg ; 213(2): 275-83, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21601488

RESUMO

BACKGROUND: Survival after resection for invasive intraductal papillary mucinous neoplasm (inv-IPMN) is superior to pancreatic ductal adenocarcinoma (PDAC). This difference may be explained by earlier presentation of inv-IPMN. We hypothesized that inv-IPMN has survival comparable with PDAC after resection when matched by stage. STUDY DESIGN: From 1999 to 2009, 113 patients underwent resection for inv-IPMN at 2 large academic institutions. These data were compared with 845 patients during the same period undergoing resection for PDAC. Demographics, pathology, and overall survival (OS) were compared according to current American Joint Committee on Cancer stage. RESULTS: Mean age with inv-IPMN and PDAC was 68 and 65 years, respectively. Follow-up was 33 and 24 months for inv-IPMN and PDAC, respectively. Median OS was 32 months for inv-IPMN and 17 months in PDAC (p < 0.001). Median OS in lymph node-negative inv-IPMN was 41 months and 24 months in PDAC (p = 0.003), with the greatest absolute difference in stage Ia patients with OS of 80 and 50 months in inv-IPMN and PDAC, respectively (p = 0.03). In node-positive patients, OS was 20 months in inv-IPMN and 15 months in PDAC (p = 0.06). Of inv-IPMN, 24% was colloid versus 75% of tubular subtype; 37(85%) of node-positive inv-IPMN were tubular subtype. Median OS was 23 and 127 months for tubular and colloid subtypes, respectively (p < 0.001). CONCLUSIONS: When matched by stage, inv-IPMN has superior survival after resection compared with PDAC. This disparity is greatest in node-negative and least in node-positive disease. These findings suggest the behaviors of inv-IPMN and PDAC, although different, converge with advancing American Joint Committee on Cancer stage because of a greater proportion of tubular subtype.


Assuntos
Adenocarcinoma Mucinoso/mortalidade , Carcinoma Ductal Pancreático/mortalidade , Pancreatectomia , Neoplasias Pancreáticas/mortalidade , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Taxa de Sobrevida
11.
J Neurovirol ; 17(1): 63-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21246320

RESUMO

Chemokines influence HIV neuropathogenesis by affecting the HIV life cycle, trafficking of macrophages into the nervous system, glial activation, and neuronal signaling and repair processes; however, knowledge of their relationship to in vivo measures of cerebral injury is limited. The primary objective of this study was to determine the relationship between a panel of chemokines in cerebrospinal fluid (CSF) and cerebral metabolites measured by proton magnetic resonance spectroscopy (MRS) in a cohort of HIV-infected individuals. One hundred seventy-one stored CSF specimens were assayed from HIV-infected individuals who were enrolled in two ACTG studies that evaluated the relationship between neuropsychological performance and cerebral metabolites. Concentrations of six chemokines (fractalkine, IL-8, IP-10, MCP-1, MIP-1ß, and SDF-1) were measured and compared with cerebral metabolites individually and as composite neuronal, basal ganglia, and inflammatory patterns. IP-10 and MCP-1 were the chemokines most strongly associated with individual cerebral metabolites. Specifically, (1) higher IP-10 levels correlated with lower N-acetyl aspartate (NAA)/creatine (Cr) ratios in the frontal white matter and higher MI/Cr ratios in all three brain regions considered and (2) higher MCP-1 levels correlated with lower NAA/Cr ratios in frontal white matter and the parietal cortex. IP-10, MCP-1, and IL-8 had the strongest associations with patterns of cerebral metabolites. In particular, higher levels of IP-10 correlated with lower neuronal pattern scores and higher basal ganglia and inflammatory pattern scores, the same pattern which has been associated with HIV-associated neurocognitive disorders (HAND). Subgroup analysis indicated that the effects of IP-10 and IL-8 were influenced by effective antiretroviral therapy and that memantine treatment may mitigate the neuronal effects of IP-10. This study supports the role of chemokines in HAND and the validity of MRS as an assessment tool. In particular, the findings identify relationships between the immune response-particularly an interferon-inducible chemokine, IP-10-and cerebral metabolites and suggest that antiretroviral therapy and memantine modify the impact of the immune response on neurons.


Assuntos
Cérebro/metabolismo , Quimiocinas/líquido cefalorraquidiano , Infecções por HIV/líquido cefalorraquidiano , HIV/patogenicidade , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Contagem de Linfócito CD4 , Cérebro/virologia , Estudos de Coortes , Creatina/análise , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade
12.
J Neurovirol ; 16(6): 435-44, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20961212

RESUMO

Cerebral metabolite disturbances occur among human immunodeficiency virus (HIV)-infected people, and are thought to reflect neuropathology, including proinflammatory processes, and neuronal loss. HIV-associated cortical atrophy continues to occur, though its basis is not well understood, and the relationship of cerebral metabolic disturbance to structural brain abnormalities in HIV has not been well delineated. We hypothesized that metabolite disturbances would be associated with reduced cortical and subcortical volumes. Cerebral volumes were measured in 67 HIV-infected people, including 10 people with mild dementia (acquired immunodeficiency syndrome [AIDS] dimentia complex [ADC] stage >1) via automated magnetic resonance imaging (MRI) segmentation. Magnetic resonance spectroscopy (MRS) was used to measure levels of cerebral metabolites N-acetylaspartate (NAA), myo-inositol (MI), choline-containing compounds (Cho), glutamate/glutamine (Glx), and creatine (Cr) from three brain regions (frontal gray matter, frontal white matter, basal ganglia). Analyses were conducted to examine the associations between MRS and cerebral volumetric measures using both absolute and relative metabolite concentrations. NAA in the mid-frontal gray matter was most consistently associated with cortical (global, frontal, and parietal), ventricular, and caudate volumes based on analysis of absolute metabolite levels, whereas temporal lobe volume was associated with basal ganglia NAA and Glx, and Cho concentrations in the frontal cortex and basal ganglia. Hippocampal volume was associated with frontal white matter NAA, whereas thalamic volume was associated with both frontal white matter NAA and basal ganglia Glx. Analyses of relative metabolite concentrations (referenced to Cr) yielded weaker effects, although more metabolites were retained as significant predictors in the models than the analysis of absolute concentrations. These findings demonstrate that reduced cortical and subcortical volumes, which have been previously found to be linked to HIV status and history, are also strongly associated with the degree of cerebral metabolite disturbance observed via MRS. Reduced cortical and hippocampal volumes were most strongly associated with decreased NAA, though reduced Glx also tended to be associated with reduced cortical and subcortical volumes (caudate and thalamus) as well, suggesting both neuronal and glial disturbances. Interestingly, metabolite-volumetric relationships were not limited to the cortical region from which MRS was measured, possibly reflecting shared pathophysiological processes. The relationships between Cho and volumetric measures suggest a complicated relationship possibly related to the effects of inflammatory processes on brain volume. The findings demonstrate the relationship between MRI-derived measures of cerebral metabolite disturbances and structural brain integrity, which has implication in understanding HIV-associated neuropathological mechanisms.


Assuntos
Córtex Cerebral/patologia , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Adulto , Gânglios da Base/patologia , Gânglios da Base/virologia , Córtex Cerebral/virologia , Estudos de Coortes , Feminino , Lobo Frontal/patologia , Lobo Frontal/virologia , HIV/patogenicidade , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Neuroglia/metabolismo , Tálamo/patologia , Tálamo/virologia
13.
HPB (Oxford) ; 12(7): 447-55, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20815853

RESUMO

BACKGROUND: Adjuvant treatment for pancreatic adenocarcinoma has been shown to improve survival. An increasingly recognized 'subtype' of pancreatic adenocarcinoma is invasive intraductal papillary mucinous neoplasm (IPMN). It is unclear whether adjuvant treatment for invasive IPMN improves survival. This study aimed to determine the impact of adjuvant treatment in invasive IPMN. METHODS: We conducted a retrospective analysis of merged clinical databases including 412 patients undergoing resection for IPMN at two academic institutions between 1989 and 2006. RESULTS: Of 412 patients with IPMN who underwent pancreatectomy, 98 had invasive carcinoma. Median survival in invasive IPMN was 32 months. Adjuvant treatment did not affect median survival in node-positive or node-negative invasive IPMN. Biopsy-proven recurrence of invasive IPMN occurred in 45 patients (46%). The median disease-free interval from resection to recurrence was 27 months. Treatment of recurrences with chemotherapy or radiation therapy was not associated with a difference in survival; however, a subgroup of patients with recurrence in the remnant pancreas who underwent re-resection appeared to have more favourable outcomes. CONCLUSIONS: An invasive component measuring >2 cm and lymph node involvement are associated with poorer prognosis. Adjuvant therapy in invasive IPMN appears to confer no survival benefit. In selected patients with recurrence of invasive IPMN in the remnant pancreas, re-resection should be considered.


Assuntos
Carcinoma Ductal Pancreático/terapia , Neoplasias Císticas, Mucinosas e Serosas/terapia , Pancreatectomia , Neoplasias Pancreáticas/terapia , Idoso , Biópsia , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/secundário , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Indiana , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Minnesota , Invasividade Neoplásica , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Neoplasias Císticas, Mucinosas e Serosas/mortalidade , Neoplasias Císticas, Mucinosas e Serosas/secundário , Pancreatectomia/mortalidade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Reoperação , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
14.
J Neurovirol ; 16(1): 25-32, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20113183

RESUMO

Cerebral atrophy is a well-described, but poorly understood complication of human immunodeficiency virus (HIV) infection. Despite reduced prevalence of HIV-associated dementia in the highly active antiretroviral therapy (HAART) era, HIV continues to affect the brains of patients with chronic infection. In this study we examine patterns of brain volume loss in HIV-infected patients on HAART, and demographic and clinical factors contributing to brain volume loss. We hypothesized that nadir CD4+ lymphocyte count, duration of HIV infection, and age would be associated with reduced cortical volumes. Volumes of cortical and subcortical regions in 69 HIV-infected neuroasymptomatic (NA) individuals and 13 with at least mild acquired immunodeficiency syndrome (AIDS) dementia complex (ADC) were measured using voxel-based morphometry. Demographic and clinical factors (age, plasma HIV RNA level, current and nadir CD4 counts, duration of infection, central nervous system [CNS] penetration of antiretroviral regimen) along with their interactions were entered into a regression model selection algorithm to determine the final models that best described regional brain volumes. Relative to NA, individuals with ADC exhibited decreased total gray matter and parietal cortex volumes and increased total ventricular volumes. Final regression models showed overall cerebral volume, including gray and white matter volume and volumes of the parietal, temporal, and frontal lobes and the hippocampus, were most strongly associated with disease history factors (nadir CD4 and duration of infection). In contrast, basal ganglia volumes were related most strongly to current disease factors, most notably plasma HIV RNA. These findings indicate that individuals with a history of chronic HIV infection with previous episodes of severely impaired immune function, as reflected by reduced nadir CD4+ lymphocyte count, may be at greatest risk for cerebral atrophy. The pattern of HIV-associated brain loss may be changing from a subcortical to a cortical disease among patients who are largely asymptomatic on HAART.


Assuntos
Complexo AIDS Demência/imunologia , Complexo AIDS Demência/patologia , Terapia Antirretroviral de Alta Atividade , Encéfalo/patologia , Complexo AIDS Demência/tratamento farmacológico , Complexo AIDS Demência/virologia , Adulto , Fatores Etários , Encéfalo/efeitos dos fármacos , Encéfalo/virologia , Contagem de Linfócito CD4 , Simulação por Computador , Feminino , HIV , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Tamanho do Órgão , Fatores de Tempo , Carga Viral
15.
Int J Radiat Oncol Biol Phys ; 76(3): 789-95, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19473777

RESUMO

PURPOSE: Routine assessment was made of tumor metabolic activity as measured by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in Stage I non-small-cell lung cancer (NSCLC). This report describes PET correlates prospectively collected after stereotactic body radiotherapy (SBRT) for patients with medically inoperable NSCLC. METHODS AND MATERIALS: 14 consecutive patients with medically inoperable Stage I NSCLC were enrolled. All patients received SBRT to 60-66 Gy in three fractions. Patients underwent serial planned FDG-PET/computed tomography fusion imaging before SBRT and at 2, 26, and 52 weeks after SBRT. RESULTS: With median follow-up of 30.2 months, no patients experienced local failure. One patient developed regional failure, 1 developed distant failure, and 1 developed a second primary. The median tumor maximum standardized uptake value (SUV(max)) before SBRT was 8.70. The median SUV(max) values at 2, 26, and 52 weeks after SBRT were 6.04, 2.80, and 3.58, respectively. Patients with low pre-SBRT SUV were more likely to experience initial 2-week rises in SUV, whereas patients with high pre-SBRT SUV commonly had SUV declines 2 weeks after treatment (p = 0.036). Six of 13 patients had primary tumor SUV(max) >3.5 at 12 months after SBRT but remained without evidence of local disease failure on further follow-up. CONCLUSIONS: A substantial proportion of patients may have moderately elevated FDG-PET SUV(max) at 12 months without evidence of local failure on further follow-up. Thus, slightly elevated PET SUV(max) should not be considered a surrogate for local treatment failure. Our data do not support routine serial FDG-PET/computed tomography for follow-up of patients receiving SBRT for Stage I NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Fluordesoxiglucose F18 , Neoplasias Pulmonares , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Radiocirurgia/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Projetos Piloto , Estudos Prospectivos , Radiocirurgia/efeitos adversos
16.
HPB Surg ; 2009: 404520, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19461951

RESUMO

Pancreatic fistula continues to be a common complication following PD. This study seeks to identify clinical factors which may predict pancreatic fistula (PF) and evaluate the effect of PF on outcomes following pancreaticoduodenectomy (PD). We performed a retrospective analysis of a clinical database at an academic tertiary care hospital with a high volume of pancreatic surgery. Five hundred ten consecutive patients underwent PD, and PF occurred in 46 patients (9%). Perioperative mortality of patients with PF was 0%. Forty-five of 46 PF (98%) closed without reoperation with a mean time to closure of 34 days. Patients who developed PF showed a higher incidence of wound infection, intra-abdominal abscess, need for reoperation, and hospital length of stay. Multivariate analysis demonstrated an invaginated pancreatic anastomosis and closed suction intraperitoneal drainage were associated with PF whereas a diagnosis of chronic pancreatitis and endoscopic stenting conferred protection. Development of PF following PD in this series was predicted by gender, preoperative stenting, pancreatic anastomotic technique, and pancreas pathology. Outcomes in patients with PF are remarkable for a higher rate of septic complications, longer hospital stays, but in this study, no increased mortality.


Assuntos
Fístula Pancreática/etiologia , Pancreaticoduodenectomia , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Anastomose Cirúrgica , Feminino , Humanos , Incidência , Indiana/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Fístula Pancreática/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Estatísticas não Paramétricas
17.
Int J Radiat Oncol Biol Phys ; 75(3): 677-82, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19251380

RESUMO

PURPOSE: The 50-month results of a prospective Phase II trial of stereotactic body radiation therapy (SBRT) in medically inoperable patients are reported. METHODS AND MATERIALS: A total of 70 medically inoperable patients had clinically staged T1 (34 patients) or T2 (36 patients) (< or =7 cm), N0, M0, biopsy-confirmed non-small-cell lung carcinoma (NSCLC) and received SBRT as per our previously published reports. The SBRT treatment dose of 60-66 Gy was prescribed to the 80% isodose volume in three fractions. RESULTS: Median follow-up was 50.2 months (range, 1.4-64.8 months). Kaplan-Meier local control at 3 years was 88.1%. Regional (nodal) and distant recurrence occurred in 6 (8.6%) and 9 (12.9%) patients, respectively. Median survival (MS) was 32.4 months and 3-year overall survival (OS) was 42.7% (95% confidence interval [95% CI], 31.1-54.3%). Cancer-specific survival at 3 years was 81.7% (95% CI, 70.0-93.4%). For patients with T1 tumors, MS was 38.7 months (95% CI, 25.3-50.2) and for T2 tumors MS was 24.5 months (95% CI, 18.5-37.4) (p = 0.194). Tumor volume (< or =5 cc, 5-10 cc, 10-20 cc, >20 cc) did not significantly impact survival: MS was 36.9 months (95% CI, 18.1-42.9), 34.0 (95% CI, 16.9-57.1), 32.8 (95% CI, 21.3-57.8), and 21.4 months (95% CI, 17.8-41.6), respectively (p = 0.712). There was no significant survival difference between patients with peripheral vs. central tumors (MS 33.2 vs. 24.4 months, p = 0.697). Grade 3 to 5 toxicity occurred in 5 of 48 patients with peripheral lung tumors (10.4%) and in 6 of 22 patients (27.3%) with central tumors (Fisher's exact test, p = 0.088). CONCLUSION: Based on our study results, use of SBRT results in high rates of local control in medically inoperable patients with Stage I NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Radiocirurgia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/secundário , Intervalos de Confiança , Seguimentos , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Estudos Prospectivos , Radiocirurgia/efeitos adversos , Dosagem Radioterapêutica , Análise de Sobrevida , Carga Tumoral
18.
Ann Surg ; 246(4): 644-51; discussion 651-4, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17893501

RESUMO

OBJECTIVE: Determine whether size and other preoperative parameters predict malignant or invasive intraductal papillary mucinous neoplasia (IPMN). SUMMARY BACKGROUND DATA: From 1991 to 2006, 150 patients underwent 156 operations for IPMN. METHODS: Prospectively collected, retrospective review of a single academic institution's experience. All preoperative parameters including a detailed radiologic-based classification of IPMN type, location, distribution, size, number, cytology, and mural nodularity were correlated with IPMN pathology. RESULTS: Malignant IPMN was present in 32% of cases, whereas 19% of cases were invasive. IPMN type and main pancreatic duct diameter were significant predictors of malignant IPMN (P<0.001). Side-branch lesion number was negatively associated with invasive IPMN (P=0.03). Side-branch size, location, and distribution did not predict IPMN pathology. The presence of mural nodules was associated with malignant and invasive IPMN (P<0.001; P<0.02). Atypical cytopathology was significantly associated with malignant and invasive IPMN (P<0.001; P<0.001). Multivariate analysis demonstrated mural nodularity and atypical cytopathology were predictive of malignancy and/or invasion in branch-type IPMN. CONCLUSIONS: To lower the rate of invasive pathology, surgery should be recommended for fit patients with main-duct IPMN and for branch-duct IPMN with mural nodularity or positive cytology irrespective of location, distribution, or size.


Assuntos
Adenocarcinoma Mucinoso/patologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Papilar/patologia , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica/patologia , Estudos de Coortes , Feminino , Previsões , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Pancreatectomia , Pancreaticoduodenectomia , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida
19.
Oncologist ; 12(1): 99-106, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17227904

RESUMO

Thalidomide has direct antimyeloma and immunomodulatory effects. In addition, both thalidomide and metronomic chemotherapy inhibit angiogenesis. The synergy of such a combination may decrease toxicity while maintaining efficacy. The Hoosier Oncology Group conducted a phase II trial of oral cyclophosphamide (50 mg b.i.d. for 21 days), thalidomide (200 mg/day), and prednisone (50 mg q.o.d.) (CTP) per 28-day course in patients with relapsed multiple myeloma (MM). Of the 37 patients enrolled, 16 had prior stem cell transplantation. The median follow-up time was 25.3 months (95% confidence interval [CI] 23.2-27.7). Of 35 patients treated, 22 patients (62.9%) responded: 7 (20.0%) complete responses, 2 (5.7%) near-complete responses, and 13 (37.1%) partial responses. Eight patients (22.9%) had stable disease, and three (8.6%) had disease progression. Two patients withdrew from the study early due to reasons unrelated to progression or toxicity and were treated as nonresponders. The median time to best response and time to progression were 3.6 months (95% CI 2.8-10.9) and 13.2 months (95% CI 9.4-21.0), respectively. The median number of treatment cycles was seven (range 1-12 cycles). Grade III to IV toxicities included leukopenia (42.9%; febrile neutropenia, 11.4%), hyperglycemia (20%), sensory neuropathy (11.4%), thromboses (8%), and motor neuropathy (5.7%). No patient withdrew from the study due to toxicity. The efficacy and low toxicity of the CTP regimen support the future development of such an approach in MM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/efeitos adversos , Mieloma Múltiplo/tratamento farmacológico , Prednisona/efeitos adversos , Talidomida/efeitos adversos , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Recidiva , Talidomida/administração & dosagem , Resultado do Tratamento
20.
J Neurovirol ; 12(4): 328-31, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16966223

RESUMO

Distal sensory polyneuropathy (DSP) is the most frequent neurological complication of HIV infection. Neuropathic symptoms vary from mild paresthesias to severe pain that respond only partially to symptomatic treatment. Forty-five subjects with human immunodeficiency virus (HIV)-associated symptomatic DSP (SDSP) were enrolled in a randomized, multicenter, 16-week placebo-controlled study of memantine, an N-methyl-D-aspartate (NMDA) uncompetitive antagonist. Although memantine was well tolerated, no trend toward clinical benefit was observed. Results were similar to those of other pilot studies of memantine for neuropathic pain unrelated to HIV, suggesting that memantine is ineffective for the symptomatic treatment of HIV-associated SDSP.


Assuntos
Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Infecções por HIV/complicações , HIV/crescimento & desenvolvimento , Memantina/uso terapêutico , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/virologia , Adulto , Feminino , Humanos , Masculino , Placebos
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