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1.
Lasers Med Sci ; 25(6): 881-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19802717

RESUMO

The objective of this study was to evaluate the influence of various pulse widths with different energy parameters of erbium:yttrium-aluminum-garnet (Er:YAG) laser (2.94 mum) on the morphology and microleakage of cavities restored with composite resin. Identically sized class V cavities were prepared on the buccal surfaces of 54 bovine teeth by high-speed drill (n = 6, control, group 1) and prepared by Er:YAG laser (Fidelis 320A, Fotona, Slovenia) with irradiation parameters of 350 mJ/ 4 Hz or 400 mJ/2 Hz and pulse width: group 2, very short pulse (VSP); group 3, short pulse (SP); group 4, long pulse (LP); group 5, very long pulse (VLP). All cavities were filled with composite resin (Z-250-3 M), stored at 37 degrees C in distilled water, polished after 24 h, and thermally stressed (700 cycles/5-55 degrees C). The teeth were impermeabilized, immersed in 50% silver nitrate solution for 8 h, sectioned longitudinally, and exposed to Photoflood light for 10 min to reveal the stain. The leakage was evaluated under stereomicroscope by three different examiners, in a double-blind fashion, and scored (0-3). The results were analyzed by Kruskal-Wallis test (P > 0.05) and showed that there was no significant differences between the groups tested. Under scanning electron microscopy (SEM) the morphology of the cavities prepared by laser showed irregular enamel margins and dentin internal walls, and a more conservative pattern than that of conventional cavities. The different power settings and pulse widths of Er:YAG laser in cavity preparation had no influence on microleakage of composite resin restorations.


Assuntos
Preparo da Cavidade Dentária/métodos , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Animais , Bovinos , Resinas Compostas , Esmalte Dentário/efeitos da radiação , Esmalte Dentário/ultraestrutura , Infiltração Dentária/prevenção & controle , Restauração Dentária Permanente/métodos , Dentina/efeitos da radiação , Dentina/ultraestrutura , Técnicas In Vitro , Microscopia Eletrônica de Varredura
2.
Rev Soc Bras Med Trop ; 41(3): 288-92, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18719810

RESUMO

Adult T-cell leukemia/lymphoma is a lymphoproliferative disorder of mature T lymphocytes associated with infection with human T-cell lymphotrophic virus type I (HTLV-I). Adult T-cell leukemia/lymphoma is characterized by clinical and laboratory polymorphism that allows it to be classified into four distinct subgroups: smoldering, chronic, acute and lymphomatous types. We present here two cases of adult T-cell leukemia/lymphoma, respectively in the acute and lymphomatous forms of the disease. Case 1 was a 35-year-old woman who presented abdominal distension accompanied by hepatosplenomegaly, adenomegaly, skin lesions, positivity for anti-HTLV-I antibodies and leukocytosis with the presence of flower cells. Case 2 was a 38-year-old man who was admitted with generalized lymphadenomegaly, positivity for anti-HTLV-I antibodies, hypercalcemia and osteolytic lesions. In this paper, we correlate the clinical-laboratory findings of these two cases with data in the literature.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Adulto , Evolução Fatal , Feminino , Humanos , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Masculino , Resultado do Tratamento
3.
Photomed Laser Surg ; 36(8): 439-444, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29768091

RESUMO

OBJECTIVE AND BACKGROUND: The correct selections of the cementing agent, the endodontic post material and placement protocol are critical to provide an increased longevity of the teeth that went through endodontic treatment. The irradiation with diode laser before post cementation, can promote an antimicrobial effect. However, there is a lack of information about the effect of 830 nm diode laser on the post bond strength. This study analyzed the effect of dentin root canal irradiation with high-intensity diode laser, at 830 nm, operating in continuous or pulsed mode, on the retention of metal or fiber posts, cemented with self-etching resinous composite (Panavia F) and zinc phosphate cement (ZnPO4). MATERIALS AND METHODS: Human roots were irradiated with diode laser (continuous and pulsed mode). The fiber posts were luted with Panavia F and the metal posts with Panavia F or ZnPO4 cement. Specimens were sectioned into three sections (cervical, middle, and apical). The bond strength was measured by a push-out mechanical analysis. For the statistical analysis, a three-way ANOVA test was applied following a Tukey's pairwise comparison with a significance level of p = 0.05. RESULTS: The irradiated groups presented higher bond strength compared with nonirradiated group (p < 0.05), and the cervical and middle thirds presented higher on bond strength than the apical. The association of metal post and Panavia F presented higher bond strength when irradiated on continuous mode (p < 0.05). Fiber post and Panavia F presented higher bond strength associated to pulsed mode. The mode seems not to make a significant difference. CONCLUSIONS: These results corroborate the importance of the post bond to dentin and root canal debris removal to increase the tooth longevity. It was shown that the dentin to post bond strength were enhanced by the diode laser irradiation either on continuous or pulsed modes.


Assuntos
Colagem Dentária/métodos , Cimentos Dentários/química , Lasers Semicondutores , Técnica para Retentor Intrarradicular , Preparo de Canal Radicular/métodos , Cimentos Dentários/farmacologia , Humanos , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento/efeitos dos fármacos , Resistência ao Cisalhamento/efeitos da radiação , Cimento de Fosfato de Zinco/química
4.
J Photochem Photobiol B ; 86(1): 70-6, 2007 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16979345

RESUMO

The aim of this study was to investigate the ability of malachite green (MG) combined with a low-power red laser to kill Actinobacillus actinomycetemcomitans and to investigate MG photodegradation after photodynamic therapy (PDT) by optical absorption spectroscopy. The etiology of periodontal disease is that microorganisms form a bacterial biofilm on the surface of the teeth. It is an infectious disease and A. actinomycetemcomitans is considered an important agent in biofilm ecology. Instead of using antibiotics, PDT is an alternative approach to eradicate bacteria. Cultures of A. actinomycetemcomitans were exposed to a 30 mW diode red laser, in the presence or absence of MG. A group of cultures was treated in dark conditions in the presence of MG (0.01% w/v) for 5 min. In the presence of MG, two exposure times for laser irradiation were used: t=3 min (energy dose=5.4 J/cm(2)), and t=5 min (energy dose=9 J/cm(2)). The samples were diluted and bacterial colonies were counted and converted into colony forming units. Absorption spectra of the bacterial suspensions, MG, MG-stained bacterial suspensions, and photosensitized bacterial suspensions were obtained. A. actinomycetemcomitans can be photoinactivated by a red laser in the presence of MG. Significant differences were observed between the two energy doses used (p<0.05). Red laser alone and MG alone were not able to kill bacteria. Optical absorption showed that MG is photobleached after irradiation. These results indicate that A. actinomycetemcomitans can be photosensitized by red laser combined with MG and that the dye is photodegraded following irradiation.


Assuntos
Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Fotoquimioterapia/métodos , Corantes de Rosanilina/farmacologia , Aggregatibacter actinomycetemcomitans/efeitos da radiação , Técnicas Bacteriológicas , Estabilidade de Medicamentos , Humanos , Lasers , Doenças Periodontais/etiologia , Doenças Periodontais/microbiologia , Doenças Periodontais/terapia , Corantes de Rosanilina/efeitos da radiação , Corantes de Rosanilina/uso terapêutico
5.
Rev Soc Bras Med Trop ; 40(3): 321-5, 2007.
Artigo em Português | MEDLINE | ID: mdl-17653469

RESUMO

The aim of this study was to evaluate platelet activation through P-selectin, and PDGF-AB and TGF beta 1 content, in schistosomiasis patients who developed fibrosis (F3) and who did not present this (F0), and in a control group (C). The results showed that the percentage of P-selectin in platelets without agonist stimulation was 10.6% in F3, 11.1% in F0 and 6.3% in C. After the addition of ADP/adrenaline, the percentages were 44%, 25.3% and 42%, respectively. The PDGF-AB and TGF beta 1 contents per platelet were 11,016 ng/dl (F3), 3,172 ng/dl (F0) and 5.01 ng/dl (C) and 0,012 ng/dl (F3), 5.27 ng/dl (F0) and 4.66 ng/dl (C), respectively. Concerning the P-selectin, we can conclude that platelets from patients with schistosomiasis continued to be responsive to agonists, despite being pre-activated. There were no differences in TGF beta 1 between the groups, but the PDGF-AB content was significantly higher in F3. This suggests that PDGF-AB may have some participation in the development of fibrosis.


Assuntos
Cirrose Hepática/sangue , Selectina-P/sangue , Ativação Plaquetária/fisiologia , Fator de Crescimento Derivado de Plaquetas/análise , Esquistossomose mansoni/sangue , Fator de Crescimento Transformador beta1/sangue , Estudos de Casos e Controles , Humanos , Cirrose Hepática/parasitologia , Cirrose Hepática/fisiopatologia , Contagem de Plaquetas , Esquistossomose mansoni/complicações , Esquistossomose mansoni/fisiopatologia
6.
Acta Biol Hung ; 57(2): 191-200, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16841470

RESUMO

Since ancient times propolis has been employed for many human purposes because to their favourable properties. Blood constituents labeled with technetium-99m (99mTc) have been used in nuclear medicine procedures. Some authors have reported that synthetic or natural drugs can interfere with the labeling of blood constituents with 99mTc. The aim of this work was to evaluate the action of a propolis extract on the labeling of blood elements with 99mTc. Samples of whole blood of male Wistar rats were incubated in sequence with an aqueous propolis extract at different concentrations, stannous chloride and 99mTc, as sodium pertechnetate. Blood samples were centrifuged to separate plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were also separated after precipitation in trichloroacetic acid solution and centrifugation. The radioactivity was counted and the percentage of incorporated radioactivity (%ATI) for each fraction was calculated. The data obtained showed that the aqueous propolis extract used decreased significantly the %ATI in plasma proteins at higher concentration studied. Results suggest that at high concentration the constituents of this extract could alter the labeling of plasma proteins competing with same binding sites of the 99mTc on the plasma proteins or acting as antioxidant compounds.


Assuntos
Anti-Infecciosos/química , Células Sanguíneas/química , Plasma/química , Própole/química , Tecnécio/química , Animais , Humanos , Marcação por Isótopo , Masculino , Extratos Vegetais/química , Ratos , Ratos Wistar
7.
J Biomed Opt ; 21(2): 28001, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26882450

RESUMO

Spasticity is a motor disorder frequently present in individuals with cerebral palsy (CP). This study aimed to evaluate the effect of low-level laser therapy (LLLT) on the spasticity of the masseter and anterior temporal muscle fibers in children with CP over three weeks of intermittent laser exposures. The bite force (BF) of the masticatory muscles and the amplitude of mouth opening were evaluated before and after laser irradiation in 30 children with CP. Both sides of the masseter and temporalis muscles were irradiated with low-intensity diode laser pulses of 808-nm wavelength six times over three consecutive weeks. During the subsequent three weeks of postlaser exposures, although no laser treatment was applied, the evaluation parameters were measured and recorded. A significant improvement in the amplitude of mouth opening and a decrease in the BF were observed in the weeks following LLLT (P<0.05 ). However, by the sixth week post-LLLT, the BF and the amplitude of mouth opening reverted to values equivalent to those obtained before the first application of LLLT. Our investigation revealed low-level energy exposures from a 808-nm diode laser to be an effective short-term therapeutic tool. This method increased the amplitude of mouth opening and decreased the muscle tonus of children with spastic CP over a time course of three weeks of intermittent laser applications.


Assuntos
Paralisia Cerebral/complicações , Terapia com Luz de Baixa Intensidade , Músculos da Mastigação/fisiopatologia , Espasticidade Muscular/radioterapia , Adolescente , Força de Mordida , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Espasticidade Muscular/etiologia , Espasticidade Muscular/fisiopatologia , Amplitude de Movimento Articular
8.
Rev Bras Hematol Hemoter ; 37(3): 153-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26041416

RESUMO

Irradiation of blood components with ionizing radiation generated by a specific device is recommended to prevent transfusion-associated graft-versus-host disease. However, a linear accelerator can also be used in the absence of such a device, which is the case of the blood bank facility studied herein. In order to evaluate the quality of the irradiated packed red blood cells, this study aimed to determine whether the procedure currently employed in the facility is effective in inhibiting the proliferation of T lymphocytes without damaging blood components. The proliferation of T lymphocytes, plasma potassium levels, and the degree of hemolysis were evaluated and compared to blood bags that received no irradiation. Packed red blood cell bags were irradiated at a dose of 25Gy in a linear accelerator. For this purpose, a container was designed to hold the bags and to ensure even distribution of irradiation as evaluated by computed tomography and dose-volume histogram. Irradiation was observed to inhibit the proliferation of lymphocytes. The percentage of hemolysis in irradiated bags was slightly higher than in non-irradiated bags (p-value >0.05), but it was always less than 0.4% of the red cell mass. Although potassium increased in both groups, it was more pronounced in irradiated red blood cells, especially after seven days of storage, with a linear increase over storage time. The findings showed that, at an appropriate dosage and under validated conditions, the irradiation of packed red blood cells in a linear accelerator is effective, inhibiting lymphocyte proliferation but without compromising the viability of the red cells.

9.
Rev Soc Bras Med Trop ; 37(3): 248-51, 2004.
Artigo em Português | MEDLINE | ID: mdl-15330066

RESUMO

In order to verify the viability of platelet concentrate during its preservation period when added with two trypanosomicidal chemical substances, gentian violet and quinoline WR6026, we tested these concentrates and verified the following parameters: number of platelets, pH and platelet aggregation test with a pair of agonists. Significant alterations were observed in the platelet concentrate treated with gentian violet suggesting important damage to the platelet viability. With WR6026 similar values to the controls were observed, opening new perspectives for the utilization of this salt for the chemoprophylaxis of transfusional Chagas' disease in highly endemic regions.


Assuntos
Aminoquinolinas/farmacologia , Plaquetas/efeitos dos fármacos , Preservação de Sangue/métodos , Violeta Genciana/farmacologia , Tripanossomicidas/farmacologia , Análise de Variância , Animais , Humanos , Contagem de Plaquetas , Fatores de Tempo
10.
Rev Bras Hematol Hemoter ; 34(5): 356-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23125544

RESUMO

OBJECTIVE: Iron deficiency is the most common cause of anemia and one of the main factors in the clinical deferral of blood donors. This fact prompted the current study that aimed to determine the prevalence and etiology of anemia in blood donor candidates and to evaluate the hematological screening technique used for the exclusion of these donors. METHODS: This was a prospective study that compared two groups (Anemic and Non-anemic). Initially screening for anemia was performed by manually measuring hemoglobin (Bioclin(®) Kit); the results were subsequently compared with an automated screening method (Coulter T-890). The etiology was investigated by hemoglobin electrophoresis in alkaline and acid pH, Hb A2 dosage and measurement of the ferritin concentration by immunoagglutination. Differences and associations of interest were analyzed using the Yates and McNemar's Chi-square tests and the Fisher, Mann-Whitney, Wilcoxon and Kruskal-Wallis tests. RESULTS: The deferral rate due to anemia was 4.2%; iron deficiency was identified in 37.5% and beta thalassemia in 9.3% of the excluded candidates. There was a significant discrepancy between the two techniques used to measure hemoglobin with 38.1% of initially deferred donors presenting normal hemoglobin levels by the automated method. CONCLUSION: The results show a high rate of blood donors being deferred for anemia and confirm that iron deficiency is the most prevalent cause. The discrepancies found by comparing screening methods suggest that hemoglobin and hematocrit levels should be confirmed before deferring a donor due to anemia; this may increase supplies in blood banks.

11.
Rev Bras Hematol Hemoter ; 34(3): 206-11, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23049421

RESUMO

BACKGROUND: Several irregular red blood cell alloantibodies, produced by alloimmunization of antigens in transfusions or pregnancies, have clinical importance because they cause hemolysis in the fetus and newborn and in transfused patients. OBJECTIVE: a prospective analysis of patients treated by the surgical and clinical emergency services of Hospital de Clínicas of the Universidade Federal do Triângulo Mineiro (HC/UFTM), Brazil was performed to correlate alloimmunization to clinical and epidemiological data. METHODS: Blood samples of 143 patients with initial negative antibody screening were collected at intervals for up to 15 months after the transfusion of packed red blood cells. Samples were submitted to irregular antibody testing and, when positive, to the identification and serial titration of alloantibodies. The Fisher Exact test and Odds Ratio were employed to compare proportions. RESULTS: Fifteen (10.49%) patients produced antibodies within six months of transfusion. However, for 60% of these individuals, the titers decreased and disappeared by 15 months after transfusion. Anti-K antibodies and alloantibodies against antigens of the Rh system were the most common; the highest titer was 1:32 (anti-K). There was an evident correlation with the number of transfusions. CONCLUSIONS: Given the high incidence of clinically important red blood cell alloantibodies in patients transfused in surgical and clinical emergency services, we suggest that phenotyping and pre-transfusion compatibilization for C, c, E, e (Rh system) and K (Kell system) antigens should be extended to all patients with programmed surgeries or acute clinical events that do not need emergency transfusions.

13.
Clinics (Sao Paulo) ; 66(1): 35-40, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21437433

RESUMO

OBJECTIVES: To identify the occurrence and the causes of platelet refractoriness in oncohematologic patients. INTRODUCTION: Platelet refractoriness (unsatisfactory post-transfusion platelet increment) is a severe problem that impairs the treatment of oncohematologic patients and is not routinely investigated in most Brazilian services. METHODS: Forty-four episodes of platelet concentrate transfusion were evaluated in 16 patients according to the following parameters: corrected count increment, clinical conditions and detection of anti-platelet antibodies by the platelet immunofluorescence test (PIFT) and panel reactive antibodies against human leukocyte antigen class I (PRA-HLA). RESULTS: Of the 16 patients evaluated (median age: 53 years), nine (56%) were women, seven of them with a history of pregnancy. An unsatisfactory increment was observed in 43% of the transfusion events, being more frequent in transfusions of random platelet concentrates (54%). Platelet refractoriness was confirmed in three patients (19%), who presented immunologic and non-immunologic causes. Alloantibodies were identified in eight patients (50%) by the PIFT and in three (19%) by the PRA-HLA. Among alloimmunized patients, nine (64%) had a history of transfusion, and three as a result of pregnancy (43%). Of the former, two were refractory (29%). No significant differences were observed, probably as a result of the small sample size. CONCLUSION: The high rate of unsatisfactory platelet increment, refractoriness and alloimmunization observed support the need to set up protocols for the investigation of this complication in all chronically transfused patients, a fundamental requirement for the guarantee of adequate management.


Assuntos
Plaquetas/imunologia , Neoplasias Hematológicas/sangue , Transfusão de Plaquetas/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Plaquetas Humanas/imunologia , Feminino , Imunofluorescência , Antígenos HLA/imunologia , Humanos , Isoanticorpos/imunologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Fatores Sexuais , Trombocitopenia/sangue , Trombocitopenia/terapia , Adulto Jovem
14.
Rev. bras. hematol. hemoter ; 37(3): 153-159, May-Jun/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-752538

RESUMO

Irradiation of blood components with ionizing radiation generated by a specific device is recommended to prevent transfusion-associated graft-versus-host disease. However, a lin- ear accelerator can also be used in the absence of such a device, which is the case of the blood bank facility studied herein. In order to evaluate the quality of the irradiated packed red blood cells, this study aimed to determine whether the procedure currently employed in the facility is effective in inhibiting the proliferation of T lymphocytes without damaging blood components. The proliferation of T lymphocytes, plasma potassium levels, and the degree of hemolysis were evaluated and compared to blood bags that received no irradiation. Packed red blood cell bags were irradiated at a dose of 25 Gy in a linear accelerator. For this purpose, a container was designed to hold the bags and to ensure even distribution of irradiation as evaluated by computed tomography and dose-volume histogram. Irradiation was observed to inhibit the proliferation of lymphocytes. The percentage of hemolysis in irradiated bags was slightly higher than in non-irradiated bags (p-value >0.05), but it was always less than 0.4% of the red cell mass. Although potassium increased in both groups, it was more pronounced in irradiated red blood cells, especially after seven days of storage, with a linear increase over storage time. The findings showed that, at an appropriate dosage and under validated conditions, the irradiation of packed red blood cells in a linear accelerator is effective, inhibiting lymphocyte proliferation but without compromising the viability of the red cells.


Assuntos
Segurança do Sangue , Eritrócitos , Serviço de Hemoterapia , Aceleradores de Partículas , Radiação , Radiação Ionizante , Linfócitos T
15.
Rev. latinoam. bioét ; 12(2): 118-123, jul.-dic. 2012.
Artigo em Inglês | LILACS | ID: lil-675359

RESUMO

The text examines the article 11 of the Universal Declaration on Bioethics and Human Rights of UNESCO that deals with the principle of non-discrimination and non-stigmatization. Both concepts are related to the theme of human dignity, while discrimination is an inherent part of stigma: stigma does not exist if there is no discrimination. In this context, this paper aims to study the relationship between stigma, discrimination and HIV / AIDS. The study argues that to loosen the bonds that hold the subjects that are attached to them is necessary questioning the broader forces - social, cultural, political and economic - that structure stigma, stigmatization and discrimination as social processes directly linked to production and reproduction of structural inequalities...


El texto analiza el artículo 11 de la Declaración Universal sobre Bioética y Derechos Humanos de la Unesco que trata del principio de la no-discriminación y la no-estigmatización. Ambos conceptos están relacionados con el tema de la dignidad humana, al mismo tiempo en que la discriminación es parte inherente del estigma; no existe estigma si no hay discriminación. En este contexto, el trabajo pretende estudiar la relación entre estigma, discriminación y el HIV/Sida. El estudio defiende que para soltar las amarras que prenden los sujetos que están presos a ellas es necesario cuestionar las propias fuerzas más amplias – sociales, culturales, políticas y económicas – que estructuran el estigma, la estigmatización y la discriminación como procesos sociales directamente ligados a la producción y la reproducción de las desigualdades estructurales...


O texto analisa o artigo 11 da Declaração Universal sobre Bioética e Direitos Humanos da UNESCO que trata do princípio da não-discriminação e não-estigmatização. Ambos os conceitos estão relacionados com o tema da dignidade humana, ao mesmo tempo que a discriminação é parte inerente do estigma: não existe estigma se não houver discriminação. Neste contexto, o trabalho objetiva estudar a relação entre estigma, discriminação e o HIV/Aids. O estudo defende que para soltar as amarras que prendem os sujeitos que estão presos a elas é necessário questionar as próprias forças mais amplas - sociais, culturais, políticas e econômicas - que estruturam o estigma, a estigmatização e a discriminação como processos sociais diretamente ligados à produção e reprodução de desigualdades estruturais...


Assuntos
Humanos , Bioética , Direitos Humanos , Preconceito
16.
Rev. bras. hematol. hemoter ; 34(5): 356-360, 2012. tab
Artigo em Inglês | LILACS | ID: lil-654977

RESUMO

OBJECTIVE: Iron deficiency is the most common cause of anemia and one of the main factors in the clinical deferral of blood donors. This fact prompted the current study that aimed to determine the prevalence and etiology of anemia in blood donor candidates and to evaluate the hematological screening technique used for the exclusion of these donors. METHODS: This was a prospective study that compared two groups (Anemic and Non-anemic). Initially screening for anemia was performed by manually measuring hemoglobin (Bioclin® Kit); the results were subsequently compared with an automated screening method (Coulter T-890). The etiology was investigated by hemoglobin electrophoresis in alkaline and acid pH, Hb A2 dosage and measurement of the ferritin concentration by immunoagglutination. Differences and associations of interest were analyzed using the Yates and McNemar's Chi-square tests and the Fisher, Mann-Whitney, Wilcoxon and Kruskal-Wallis tests. RESULTS: The deferral rate due to anemia was 4.2%; iron deficiency was identified in 37.5% and beta thalassemia in 9.3% of the excluded candidates. There was a significant discrepancy between the two techniques used to measure hemoglobin with 38.1% of initially deferred donors presenting normal hemoglobin levels by the automated method. CONCLUSION: The results show a high rate of blood donors being deferred for anemia and confirm that iron deficiency is the most prevalent cause. The discrepancies found by comparing screening methods suggest that hemoglobin and hematocrit levels should be confirmed before deferring a donor due to anemia; this may increase supplies in blood banks.


Assuntos
Humanos , Masculino , Feminino , Doadores de Sangue , Anemia Ferropriva , Seleção do Doador
17.
Rev. bras. hematol. hemoter ; 34(3): 206-211, 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-640869

RESUMO

BACKGROUND: Several irregular red blood cell alloantibodies, produced by alloimmunization of antigens in transfusions or pregnancies, have clinical importance because they cause hemolysis in the fetus and newborn and in transfused patients. OBJECTIVE: a prospective analysis of patients treated by the surgical and clinical emergency services of Hospital de Clínicas of the Universidade Federal do Triângulo Mineiro (HC/UFTM), Brazil was performed to correlate alloimmunization to clinical and epidemiological data. METHODS: Blood samples of 143 patients with initial negative antibody screening were collected at intervals for up to 15 months after the transfusion of packed red blood cells. Samples were submitted to irregular antibody testing and, when positive, to the identification and serial titration of alloantibodies. The Fisher Exact test and Odds Ratio were employed to compare proportions. RESULTS: Fifteen (10.49%) patients produced antibodies within six months of transfusion. However, for 60% of these individuals, the titers decreased and disappeared by 15 months after transfusion. Anti-K antibodies and alloantibodies against antigens of the Rh system were the most common; the highest titer was 1:32 (anti-K). There was an evident correlation with the number of transfusions. CONCLUSIONS: Given the high incidence of clinically important red blood cell alloantibodies in patients transfused in surgical and clinical emergency services, we suggest that phenotyping and pre-transfusion compatibilization for C, c, E, e (Rh system) and K (Kell system) antigens should be extended to all patients with programmed surgeries or acute clinical events that do not need emergency transfusions.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Antígenos de Grupos Sanguíneos , Transfusão de Sangue , Imunofenotipagem , Emergências , Hemólise
18.
Clinics ; 66(1): 35-40, 2011. tab
Artigo em Inglês | LILACS | ID: lil-578593

RESUMO

OBJECTIVES: To identify the occurrence and the causes of platelet refractoriness in oncohematologic patients. INTRODUCTION: Platelet refractoriness (unsatisfactory post-transfusion platelet increment) is a severe problem that impairs the treatment of oncohematologic patients and is not routinely investigated in most Brazilian services. METHODS: Forty-four episodes of platelet concentrate transfusion were evaluated in 16 patients according to the following parameters: corrected count increment, clinical conditions and detection of anti-platelet antibodies by the platelet immunofluorescence test (PIFT) and panel reactive antibodies against human leukocyte antigen class I (PRA-HLA). RESULTS: Of the 16 patients evaluated (median age: 53 years), nine (56 percent) were women, seven of them with a history of pregnancy. An unsatisfactory increment was observed in 43 percent of the transfusion events, being more frequent in transfusions of random platelet concentrates (54 percent). Platelet refractoriness was confirmed in three patients (19 percent), who presented immunologic and non-immunologic causes. Alloantibodies were identified in eight patients (50 percent) by the PIFT and in three (19 percent) by the PRA-HLA. Among alloimmunized patients, nine (64 percent) had a history of transfusion, and three as a result of pregnancy (43 percent). Of the former, two were refractory (29 percent). No significant differences were observed, probably as a result of the small sample size. CONCLUSION: The high rate of unsatisfactory platelet increment, refractoriness and alloimmunization observed support the need to set up protocols for the investigation of this complication in all chronically transfused patients, a fundamental requirement for the guarantee of adequate management.


Assuntos
Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Plaquetas/imunologia , Neoplasias Hematológicas/sangue , Transfusão de Plaquetas/efeitos adversos , Antígenos de Plaquetas Humanas/imunologia , Imunofluorescência , Antígenos HLA/imunologia , Isoanticorpos/imunologia , Contagem de Plaquetas , Fatores Sexuais , Trombocitopenia/sangue , Trombocitopenia/terapia
19.
Rev. bras. hematol. hemoter ; 32(4): 335-336, 2010.
Artigo em Português | LILACS | ID: lil-561360

RESUMO

Despite major advances in Brazilian blood transfusion therapy with a growing number of scientific publications, an increased number of repeat donors and a decline in serological ineligibility, a lack of conformity in the application of pre-transfusion tests that may compromise transfusion safety is still observed at transfusion agencies in the fringes of the blood transfusion therapy system. Additionally, although high rates of platelet transfusion refractoriness and significant rates of alloimmunization have been demonstrated in the international literature, few Brazilian centers have been concerned with the study of platelet alloimmunization and even fewer centers have evaluated the efficacy of platelet concentrate transfusion. As more than one million Brazilians, including many repeat blood donors, are listed in the National Bone Marrow Donor Registry (Redome), why not grant transfusion therapy services access to the HLA typing of these blood and marrow donors after obtaining their consent? And why not make use of the Redome data to evaluate the HLA compatibility of donors for alloimmunized patients who are candidates for bone marrow transfusion and who have already been typed? These measures, together with the identification of ABO and HPA antigens, will permit a complete assessment of platelet immunology, will guarantee the transfusion safety of this blood component, and will put Brazil at the same level as the so-called developed countries in terms of transfusion medicine.


Assuntos
Humanos , Plaquetas , Hemoglobinas , Transfusão de Plaquetas
20.
Rev. patol. trop ; 39(4): 261-271, out.-dez. 2010. tab
Artigo em Português | LILACS | ID: lil-591472

RESUMO

Introdução: Hepatite C é causada por flavivírus e sua prevenção é feita especialmente pela triagemsorológica nos bancos de sangue. Objetivos: Calcular a prevalência de doações inaptas pelo vírus da Hepatite C (HCV), analisar o perfil epidemiológico dos inaptos e a tendência de inaptidão por HCV e verificar a concordância entre os testes ELISA e RIBA (Recombinant Immunoblot Assay). Métodos: estudo retrospectivo da sorologia das doações realizadas no Hemocentro Regional de Uberaba (HRU) entre 1995 e 2008, análise do perfil segundo valores proporcionais (para 10.000 doações), estudo de tendência através do coeficiente de correlação linear, com 5por cento de significância e análise da concordância entre ELISA e RIBA com cálculo do coeficiente kappa. Resultados: Foram realizadas, no período, 218.871 doações, sendo 814 (0,4por cento) inaptas por sorologia para o HCV pelo ELISA, com proporções superiores e estatisticamente significativas de inaptos do gênero masculino, idade igual ou superior a 30 anos, procedentes de Uberaba e casados. Houve correlação linear forte inversamente proporcional dos índices de inaptidão para HCV com os anos de estudo (r igual 0,870631). A concordância entre ELISA e RIBA foi de 46,8por cento (kappa igual 0,637). Conclusão: Por meio da análise desses resultados, demonstrou-se uma tendência decrescente de inaptidão para HCV entre doadores, indicando queda do risco de contaminação via transfusão de sangue.


Assuntos
Humanos , Doadores de Sangue , Hepacivirus , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Sorologia , Brasil/epidemiologia , Estudos Retrospectivos , Monitoramento Epidemiológico
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