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The dialectical relationship between ecosystems and society is complex; therefore, holistic approaches are required to address this complexity. This view also stands out in the ecosystem services valuation field, where different scholars and global platforms have drawn attention to the need to incorporate plural valuation initiatives at decision-making. In this sense, through a comprehensive design, we conducted a multi-layered valuation of ecosystem services, and we highlighted multiple values in two areas of the province of Caldas, Colombia. We proposed a three-phase valuation process called Recognizing, Normalizing and Articulating values. Then, in cooperation with the regional environmental authority, we obtained different water-related ecosystem services values. Our results showed some warnings: first, we found mismatches between ecosystem services values; second, people assigned high values to ecosystems but the actual capacity of ecosystems to support ES is low. Finally, monetary values were marginal compared to social and ecological values. We conclude by saying that the more strata are assessed, the more values appear in the valuation scenarios, and those values could be conflicting. Our results have political implications, since they highlight the need to incorporate plural values as a fundamental tool for planning and land use in real scenarios where conflicts of interest and values are evident.
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INTRODUCTION AND OBJECTIVES: Myocardial dysfunction contributes to early mortality (24-72 hours) among survivors of a cardiac arrest (CA). The benefits of mechanical support in refractory shock should be balanced against the patient's potential for neurological recovery. To date, these early treatment decisions have been taken based on limited information leading mainly to undertreatment. Therefore, there is a need for early, reliable, accessible, and simple tools that offer information on the possibilities of neurological improvement. METHODS: We collected data from bispectral index (BIS) and suppression ratio (SR) monitoring of adult comatose survivors of CA managed with targeted temperature management (TTM). Neurological status was assessed according to the Cerebral Performance Category (CPC) scale. RESULTS: We included 340 patients. At the first full neurological evaluation, 211 patients (62.1%) achieved good outcome or CPC 1-2. Mean BIS values were significantly higher and median SR lower in patients with CPC 1-2. An average BIS> 26 during first 12 hours of TTM predicted good outcome with 89.5% sensitivity and 75.8% specificity (AUC of 0.869), while average SR values> 24 during the first 12 hours of TTM predicted poor outcome (CPC 3-5) with 91.5% sensitivity and 81.8% specificity (AUC, 0.906). Hourly BIS and SR values exhibited good predictive performance (AUC> 0.85), as soon as hour 2 for SR and hour 4 for BIS. CONCLUSIONS: BIS/SR are associated with patients' potential for neurological recovery after CA. This finding could help to create awareness of the possibility of a better outcome in patients who might otherwise be wrongly considered as nonviable and to establish personalized treatment escalation plans.
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Parada Cardíaca , Hipotermia Induzida , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Prognóstico , Hipotermia Induzida/efeitos adversosRESUMO
AIMS: Data on the impact of COVID-19 in chronic heart failure (CHF) patients and its potential to trigger acute heart failure (AHF) are lacking. The aim of this work was to study characteristics, cardiovascular outcomes and mortality in patients with confirmed COVID-19 infection and a prior diagnosis of heart failure (HF). Further aims included the identification of predictors and prognostic implications for AHF decompensation during hospital admission and the determination of a potential correlation between the withdrawal of HF guideline-directed medical therapy (GDMT) and worse outcomes during hospitalization. METHODS AND RESULTS: Data for a total of 3080 consecutive patients with confirmed COVID-19 infection and follow-up of at least 30 days were analysed. Patients with a previous history of CHF (n = 152, 4.9%) were more prone to the development of AHF (11.2% vs. 2.1%; P < 0.001) and had higher levels of N-terminal pro brain natriuretic peptide. In addition, patients with previous CHF had higher mortality rates (48.7% vs. 19.0%; P < 0.001). In contrast, 77 patients (2.5%) were diagnosed with AHF, which in the vast majority of cases (77.9%) developed in patients without a history of HF. Arrhythmias during hospital admission and CHF were the main predictors of AHF. Patients developing AHF had significantly higher mortality (46.8% vs. 19.7%; P < 0.001). Finally, the withdrawal of beta-blockers, mineralocorticoid receptor antagonists and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers was associated with a significant increase in in-hospital mortality. CONCLUSIONS: Patients with COVID-19 have a significant incidence of AHF, which is associated with very high mortality rates. Moreover, patients with a history of CHF are prone to developing acute decompensation after a COVID-19 diagnosis. The withdrawal of GDMT was associated with higher mortality.
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Arritmias Cardíacas/epidemiologia , COVID-19/epidemiologia , Insuficiência Cardíaca/epidemiologia , Mortalidade Hospitalar , Doença Aguda/epidemiologia , Antagonistas Adrenérgicos beta/uso terapêutico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , COVID-19/complicações , Doença Crônica/epidemiologia , Desprescrições , Progressão da Doença , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Prevalência , Prognóstico , Fatores de Risco , SARS-CoV-2 , Espanha/epidemiologiaRESUMO
Four new HLA-A*02:05:01:10, A*26:01:01:30, C*07:01:01:75 and C*07:04:01:12 alleles detected in Spanish individuals.
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Antígenos HLA-A , Doadores de Tecidos , Alelos , Antígenos HLA-A/genética , Sequenciamento de Nucleotídeos em Larga Escala , HumanosRESUMO
Immunoglobulin M (IgM) monoclonal gammopathies show considerable variability, involving three different stages of presentation: IgM monoclonal gammopathy of undetermined significance (IgM-MGUS), asymptomatic Waldenström's macroglobulinemia (AWM), and symptomatic WM (SWM). Despite recent findings about the genomic and transcriptomic characteristics of such disorders, we know little about the causes of this clinical heterogeneity or the mechanisms involved in the progression from indolent to symptomatic forms. To clarify these matters, we have performed a gene expression and mutational study in a well-characterized cohort of 69 patients, distinguishing between the three disease presentations in an attempt to establish the relationship with the clinical and biological features of the patients. Results showed that the frequency of genetic alterations progressively increased from IgM-MGUS to AWM and SWM. This means that, in contrast to MYD88 p.L265P and CXCR4 WHIM mutations, present from the beginning of the pathogenesis, most of them would be acquired during the course of the disease. Moreover, the expression study revealed a higher level of expression of genes belonging to the Toll-like receptor (TLR) signaling pathway in symptomatic versus indolent forms, which was also reflected in the disease presentation and prognosis. In conclusion, our findings showed that IgM monoclonal gammopathies present higher mutational burden as the disease progresses, in parallel to the upregulation of relevant pathogenic pathways. This study provides a translational view of the genomic basis of WM pathogenesis.
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Heterogeneidade Genética , Imunoglobulina M/genética , Gamopatia Monoclonal de Significância Indeterminada/genética , Macroglobulinemia de Waldenstrom/genética , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Gamopatia Monoclonal de Significância Indeterminada/patologia , Prognóstico , Macroglobulinemia de Waldenstrom/patologiaRESUMO
Curvature and mechanics are intimately connected for thin materials, and this coupling between geometry and physical properties is readily seen in folded structures from intestinal villi and pollen grains to wrinkled membranes and programmable metamaterials. While the well-known rules and mechanisms behind folding a flat surface have been used to create deployable structures and shape transformable materials, folding of curved shells is still not fundamentally understood. Shells naturally deform by simultaneously bending and stretching, and while this coupling gives them great stability for engineering applications, it makes folding a surface of arbitrary curvature a nontrivial task. Here we discuss the geometry of folding a creased shell, and demonstrate theoretically the conditions under which it may fold smoothly. When these conditions are violated we show, using experiments and simulations, that shells undergo rapid snapping motion to fold from one stable configuration to another. Although material asymmetry is a proven mechanism for creating this bifurcation of stability, for the case of a creased shell, the inherent geometry itself serves as a barrier to folding. We discuss here how two fundamental geometric concepts, creases and curvature, combine to allow rapid transitions from one stable state to another. Independent of material system and length scale, the design rule that we introduce here explains how to generate snapping transitions in arbitrary surfaces, thus facilitating the creation of programmable multistable materials with fast actuation capabilities.
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MYD88 L265P mutation has been reported in â¼90% of Waldenström's Macroglobulinemia (WM) patients and immunoglobulin M (IgM) monoclonal gammopathies of uncertain significance (MGUS), as well as in some cases of lymphoma and chronic lymphocytic leukemia. The present study aimed to develop a real-time allele-specific oligonucleotide PCR (ASO-RQ-PCR) to detect the MYD88 L265P mutation. We first evaluated the reproducibility and sensitivity of the technique with a diluting experiment of a previously known positive sample. Then, we evaluated the applicability of the methodology by analyzing 30 selected patients (10 asymptomatic WM, 10 symptomatic WM, and 10 IgM MGUS) as well as 10 healthy donors. The quantitative ASO-PCR assay could detect the MYD88 L265P mutation at a dilution of 0.25%, showing an inverse correlation between the tumor cell percentage and the cycle threshold (CT) value, thus allowing for tumor burden quantitation. In addition, mutated cases were distinguished from the unmutated by >10 cycles of difference between CTs. To sum up, ASO-RQ-PCR is an inexpensive, robust, and optimized method for the detection of MYD88 L265P mutation, which could be considered as a useful molecular tool during the diagnostic work-up of B-cell lymphoproliferative disorders.
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Análise Mutacional de DNA/métodos , Gamopatia Monoclonal de Significância Indeterminada/diagnóstico , Mutação/genética , Fator 88 de Diferenciação Mieloide/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Macroglobulinemia de Waldenstrom/diagnóstico , Alelos , Diagnóstico Diferencial , Humanos , Imunoglobulina M/metabolismo , Gamopatia Monoclonal de Significância Indeterminada/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Tumoral , Macroglobulinemia de Waldenstrom/genéticaRESUMO
The aim of this study was to evaluate the effect of antiretroviral therapy on inflammatory markers of endothelial dysfunction in HIV treatment-naïve infected patients. This was a prospective cohort study in HIV treatment-naïve infected patients. The patients were assigned to a untreated group or a treatment group according to the therapeutic strategy received. Patients in the treatment group received efavirenz or lopinavir/ritonavir, each given with zidovudine and lamivudine. HIV RNA, CD4(+) cell count, and the levels of hsCRP, sCD40L, sICAM-1, sVCAM-1, and sE-selectin were measured before and 12 weeks after treatment. Fifty patients were enrolled: 13 in the untreated group and 37 in the treatment group; 48 (96%) completed the follow-up. The mean (± SD) age was 33 ± 9 years, and 38 (79%) were men. The median pretreatment CD4(+) cell counts were 263 cells/ml (IQR 118-341) in the treatment group and 658 cells/ml (IQR 475-887) in the untreated group. In the treatment group, the median serum sVCAM-1 and sICAM-1 levels decreased by a small but significant amount (1,400 and 228 ng/ml, respectively, P<0.05) from before to after the 12 weeks. These levels did not change in the untreated group. Antiretroviral therapy is associated with a decrease in sVCAM-1 and sICAM-1 levels after 12 weeks of treatment.
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Células Endoteliais/imunologia , Células Endoteliais/patologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Inflamação/patologia , Adulto , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4 , Estudos de Coortes , Citocinas/sangue , Feminino , Humanos , Masculino , Estudos Prospectivos , Carga ViralRESUMO
We have evaluated the use of CD138+ positively selected bone marrow samples to identify a molecular target for minimal residual disease assessment by polymerase chain reaction (PCR) in 25 untreated patients with multiple myeloma. A fraction of each sample was used for CD138+ selection, and the rest served as a reference control. VDJH, DJH, and Kde gene rearrangements were tested for amplification according to the BIOMED-2 Concerted Action. PCR products were directly sequenced in an automated ABI 3130 DNA sequencer using Big-Dye terminators. Within the CD138+ selected group, VDJH rearrangements were detected in all cases (100 %), DJH in 16 (64 %), and Kde in 18 (72 %) cases; whereas in the control samples, VDJH, DJH, and Kde rearrangements were detected in 19 (76 %), 11 (44 %), and 12 (48 %) cases, respectively. After sequencing, 24 (96 %) cases within the CD138+ group had a PCR target for MRD detection compared with 15 (60 %) cases in the control group. We conclude that the use of CD138+ positively selected bone marrow samples increases the applicability of minimal residual disease studies by PCR in patients with multiple myeloma.
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Exame de Medula Óssea/métodos , Medula Óssea/patologia , Separação Celular/métodos , Rearranjo Gênico do Linfócito B , Mieloma Múltiplo/patologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sindecana-1/análise , Células Clonais/patologia , DNA de Neoplasias/genética , Humanos , Proteínas do Mieloma/genética , Neoplasia Residual/diagnóstico , Recombinação V(D)JRESUMO
BACKGROUND: A rise of CD3+ TCRgammadelta+ CD28- T cells has previously been observed after an in vitro long-lasting activation or even during viral infection. OBJECTIVE: The aim of this study was to investigate the expression of CD28 on lymphocytes bearing CD3/TCRgammadelta receptors in cancer, i.e. cutaneous melanoma. METHODS: TCRgammadelta lymphocytes were analysed in 41 Caucasian melanoma patients and 39 healthy individuals by flow cytometry. Patients were stratified according to the American Joint Committee on Cancer (AJCC) clinical stage. RESULTS: The number of circulating CD3+ TCRgammadelta+ T cells was significantly increased in both AJCC stages I-II and AJCC stage III patients compared with healthy individuals. This increase was mediated by an accumulation of the CD3+ TCRgammadelta+ CD28- T-cell subset, which expressed a high amount of perforin both in normal individuals and melanoma patients. CONCLUSION: This work shows, for the first time, a rise of the cytotoxic CD3+ TCRgammadelta+ CD28- T-cell population in melanoma patients, which may be important in anticancer surveillance.
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Antígenos CD28/imunologia , Complexo CD3/imunologia , Melanoma/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Melanoma/sangue , Pessoa de Meia-Idade , Neoplasias Cutâneas/sangueRESUMO
The involvement of the human leukocyte antigen (HLA) in liver graft acceptance is controversial, but the frequency of acute rejection (AR) remains high in spite of the use of the modern immunosuppressive agents. The present study was aimed at determining whether an association exists between liver recipient HLA-C polymorphism and AR development that could influence graft acceptance. Four hundred and forty-six liver recipients and 473 controls were studied within the framework of a collaborative study carried out by the Spanish Transplant Immunotolerance Group (RED-GIT). HLA-A and -B were typed by the standard microlymphocytotoxicity technique, and HLA-C by polymerase chain reaction-sequence-specific oligonucleotide probes (PCR-SSOP). A statistically significant decrease in the HLA-Cw*07 allele frequency was found in liver recipients suffering AR episodes compared to those without AR (NAR). Studies regarding the possible influence of the Asn80 and Lys80 epitopes showed that the Asn80 epitope also could be associated with AR. However, further analysis considering Asn80 alleles others than HLA-Cw*07, confirmed that the apparent protective effect of the Asn80 epitope was actually from the HLA-Cw*07 allele. In conclusion, the HLA-Cw*07 allele carried by the liver recipient is negatively associated with AR development, and could be considered a predictive factor for liver graft acceptance.
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Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Antígenos HLA-C/administração & dosagem , Antígenos HLA-C/genética , Transplante de Fígado/imunologia , Doença Aguda , Alelos , Feminino , Rejeição de Enxerto/genética , Antígenos HLA-C/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos RetrospectivosRESUMO
PURPOSE: Because immune mechanisms involved in cutaneous melanoma have not been fully elucidated, efforts have been made to achieve prognosis markers and potential targets for immune therapies, but they have not been entirely fruitful thus far. Therefore, the goal of this study was to investigate the involvement of early changes in CD8 T cells and CD56 natural killer (NK) cells expressing NK receptors in different HLA-C dimorphism groups of melanoma patients. EXPERIMENTAL DESIGN: CD8 T cells and CD56 NK cells were analyzed in 41 patients and 39 sex- and age-matched controls with different HLA-C genotypes by flow cytometry. HLA-C dimorphism at position 80 was tested by PCR sequence-specific primers and PCR sequence-specific oligonucleotide to examine whether it could mediate in the emergence of cells expressing killer cell immunoglobulin-like receptors. RESULTS: Thirty-five of 41 patients had benign sentinel node, and showed an imbalance in the absolute number of CD8(+)DR(+) or CD8(+)CD161(+) peripheral blood T cells according to the CD28 coexpression compared with controls. CD8(+)CD28(-)CD158a(+) T and CD56(+)CD158a(+) NK cells were significantly increased in HLA-C(Lys80) homozygous nonmetastatic patients, whereas only CD56(+)CD158a(+) NK cells increased in heterozygous ones. An up-regulation of the CD158a KIR receptor was also seen on NK cells but not in T cells of patients at advanced disease stages. CONCLUSIONS: This work provides, for the first time, evidence of immune activation in early stages of cutaneous melanoma, together with an increase of cells expressing CD158a in patients bearing the corresponding HLA-C ligand, which may be important to evaluate the disease progression and to use individualized immune therapeutic approaches.
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Linfócitos T CD8-Positivos/imunologia , Antígenos HLA-C/imunologia , Células Matadoras Naturais/imunologia , Melanoma/imunologia , Receptores Imunológicos/imunologia , Neoplasias Cutâneas/imunologia , Adulto , Idoso , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígeno CD56/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores KIR , Receptores KIR2DL1RESUMO
Available data have led to a controversy on the relationship between human leukocyte antigen (HLA) and cutaneous malignant melanoma susceptibility or prognosis. Moreover, the influence of HLA-C on melanoma has not yet been well established. Therefore, the aim of the current study was to analyze the possible influence of the HLA system on melanoma susceptibility and prognosis in the Spanish population. For this purpose, HLA-A and HLA-B serotyping and HLA-C, HLA-DRB1, and HLA-DQB1 genotyping by polymerase chain reactions using sequence-specific oligonucleotide (PCR-SSO) and sequence-specific primer (PCR-SSP) were performed in 174 melanoma patients and 227 ethnically matched controls. The number of controls was increased up to 356 for HLA-C typing. Patients were stratified according to the histological subtypes of melanoma, sentinel lymph node status, tumor thickness, and ulceration of primary lesion. No HLA-A, HLA-B, HLA-DRB1, or HLA-DQB1 relationship with melanoma was observed for susceptibility or disease prognosis. However, the analysis of HLA-C locus showed that individuals homozygous for HLA-C(Lys80) were significantly more frequent within the patient than the control group. Remarkably, individuals homozygous for group 2 HLA-C alleles (HLA-C(Lys80)) seem to be associated with metastatic progression of melanoma. In contrast, we found a negative association between group 1 HLA-C alleles (HLA-C(Asn80)) and disease susceptibility or metastasis development. In conclusion, although an association with HLA-A, HLA-B, HLA-DRB1, or HLA-DQB1 was not demonstrated, the study of the HLA-C locus revealed that the analysis of the dimorphism at position 80 in the alpha1 helix may help to evaluate the risk and prognosis of melanoma in our population.
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Genes MHC da Classe II , Genes MHC Classe I , Antígenos HLA-C/genética , Melanoma/genética , Melanoma/imunologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Estudos de Casos e Controles , Feminino , Frequência do Gene , Humanos , Metástase Linfática , Masculino , Melanoma/secundário , Fenótipo , Prognóstico , EspanhaRESUMO
The promyelocytic leukemia zinc finger (PLZF) gene, involved in rare cases of acute promyelocytic leukemia, encodes a Krüppel-type zinc finger transcription factor. It has been reported that PLZF affects myeloid cell growth, differentiation, and apoptosis. However, the function of PLZF in the lymphoid compartment, where PLZF is also expressed, remains largely unknown. To investigate a potential relationship between PLZF expression in lymphocytes and programmed cell death, an inducible model of stable clones of the lymphoid Jurkat cell line was created by using the tet-off system. Although induction of PLZF expression by itself did not produce changes in the basal levels of apoptosis, PLZF had a significant anti-apoptotic effect in Jurkat cells cultured in conditions of serum starvation, as measured by annexin V staining and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling. In addition, retarded loss of mitochondrial transmembrane potential was observed in the PLZF-expressing clones, suggesting that PLZF protects from cell death through a mitochondrial-dependent mechanism. To identify apoptosis-related targets of PLZF, a screen for differential expression identified BID, a proapoptotic member of the Bcl2 family, as significantly down-regulated by PLZF. Furthermore, a high-affinity PLZF-binding site element was identified upstream of the BID transcriptional start site, as assessed by electrophoretic mobility-shift assays. These results suggest that BID is a target of PLZF repression and a candidate gene to mediate the PLZF-induced resistance to apoptosis.
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Apoptose , Proteínas de Transporte/genética , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Linfócitos/citologia , Linfócitos/metabolismo , Fatores de Transcrição/metabolismo , Apoptose/efeitos dos fármacos , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Meios de Cultura Livres de Soro/farmacologia , Proteínas de Ligação a DNA/genética , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Células Jurkat , Cinética , Fatores de Transcrição Kruppel-Like , Potenciais da Membrana , Regiões Promotoras Genéticas/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genéticaRESUMO
In 170 patients given primary hip or knee joint prosthesis surgery, we determined the relation between variables connected with the preoperative nutritional state and delayed healing of the surgical wound. 46 patients had a lymphocyte count of less than 1500 cells/mm3 (normal 1500-3300 cell/mm3), 18 an albumin level of less than 3.5 g/dL (normal 3.5-5 gr/dL), and 35 patients had a transferrin level of less than 200 mg/dL (normal 200-400 mg/dL). We found an association between the preoperative lymphocyte count and delay in wound healing, whereas preoperative seru albumin and transferrin levels had no significant predictive value. In addition, a preoperative lymphocyte count of less than 1500 cells/mm3 was associated with a 3 times higher frequency of healing complications.
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Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Estado Nutricional/fisiologia , Cicatrização/fisiologia , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Cuidados Pré-Operatórios , Probabilidade , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores SexuaisRESUMO
BACKGROUND: Several studies have established a relationship between the preoperative hemoglobin level and the need for postoperative blood transfusion. We analyzed the relationship between preoperative hemoglobin levels, as well as other factors such as age, gender, weight, height, type and duration of the total joint replacement surgery, and the need for postoperative blood transfusion. METHODS: A retrospective study of 296 patients treated with 370 procedures (209 total hip arthroplasties [56.5%] and 161 total knee arthroplasties [43.5%]) from 1994 to 1998 was carried out. A univariate analysis was performed to establish the relationship between all independent variables and the need for postoperative transfusion. Variables that were determined to have a significant relationship were included in a multivariate analysis. RESULTS: The univariate analysis revealed a significant relationship between the need for postoperative blood transfusion and preoperative hemoglobin levels (p = 0.0001), duration of surgery (p = 0.0001), weight (p = 0.002), height (p = 0.019), and gender (p = 0.0056). However, the multivariate analysis identified a significant relationship only between the need for transfusion and the preoperative hemoglobin level (p = 0.0001) and weight (p = 0.011); height (p = 0.776) and gender (p = 0.122) were discounted as significant factors. Patients with a preoperative hemoglobin level of <130 g/L had a four times greater risk of having a transfusion than did those with a hemoglobin level between 130 and 150 g/L and a 15.3 times greater risk than did those with a hemoglobin level of >150 g/L. CONCLUSIONS: The preoperative hemoglobin level (p = 0.0001) and weight of the patient (p = 0.011) were shown to predict the need for blood transfusion after hip and knee replacement.