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1.
J Assist Reprod Genet ; 37(9): 2081-2092, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32578032

RESUMO

PURPOSE: Intracytroplasmatic sperm injection (ICSI) is a common procedure used to improve reproductive results, even among couples without male factor infertility. However, the evidence available is still uncertain on the possible advantages and deficiencies that this procedure may have in patients with no formal indication for ICSI. METHODS: A SWOT (strengths, weaknesses, opportunities, threats) analysis examines the possible advantages and deficiencies of performing ICSI in these patients with no formal indication. RESULTS: The evidence suggests that ICSI is not justified for non-male factor infertile couples requiring in vitro conception. One of the major strengths associated to the procedure is the virtual elimination of cases further complicated by total fertilization failure and a combination between IVF and ICSI on sibling oocytes has been advised in the literature. Greater technical difficulties, higher costs and performing an unnecessary invasive technique in some cases represent some of the weaknesses of the procedure, and questions regarding safety issues should not be ruled out. CONCLUSION: Despite the widespread use of ICSI in patients without a formal diagnosis of male factor infertility, evidence demonstrating its effectiveness in this population is still lacking. Additional large and well-designed randomized controlled trials are needed to clarify definitive indications for ICSI in non-male factor infertility.


Assuntos
Fertilização in vitro/tendências , Infertilidade Masculina/genética , Injeções de Esperma Intracitoplásmicas/tendências , Espermatozoides/crescimento & desenvolvimento , Adulto , Transferência Embrionária , Feminino , Humanos , Infertilidade Masculina/terapia , Masculino , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Gravidez , Taxa de Gravidez , Sêmen/metabolismo
2.
J Pediatr Urol ; 15(5): 450.e1-450.e7, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31142443

RESUMO

INTRODUCTION: Congenital Zika syndrome (CZS) is a recently discovered condition that affects central nervous system structures that control the lower urinary tract. The first cases of neurogenic bladder (NB) were recently reported as a sequalae of CZS in neurologically impaired children. OBJECTIVE: Our goal is to further evaluate NB in the setting of CZS, identifying urological risk indicators in hopes that early diagnosis will mitigate the impact of the disease. STUDY DESIGN: Urological assessment was performed in all patients with CZS and neurological impairment who were referred to our urodynamic clinic between June 2016 and May 2018. Neurogenic bladder was confirmed by urodynamic evaluation, and urological risk was based on urodynamic results. RESULTS: Sixty-nine patients with CZS were tested. The majority (63 patients, 91.3%) presented with overactive bladder with increased pressures and reduced capacity for age (table 1). Different urodynamic patterns were observed, and the association of reduced bladder capacity for age, high bladder-filling pressure, and increased postvoid residual were frequently observed. DISCUSSION: NB continues to be consistently diagnosed in our cohort of CZS, mostly with high-risk indicators for renal impairment. When not intervened upon in a timely manner, NB can cause progressive damage to the urinary tract, but the lack of knowledge that CZS causes NB delays investigation and treatment. Parents and health professionals will need to be sensitized to the risks that ZIKV can pose to the urinary tract so that appropriate therapies are initiated to prevent irreversible renal damage. CONCLUSION: NB is a common condition among our patients with CZS and microcephaly. This is a new cause of NB, unknown to urologists. While further investigation is necessary to understand long-term disease behavior and therapeutic response, increased knowledge among urologists may help to reduce morbidity related to untreated NB and to mitigate the disease burden for patients and families.


Assuntos
Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinária/fisiopatologia , Urodinâmica/fisiologia , Urologistas , Infecção por Zika virus/complicações , Zika virus , Pré-Escolar , Diagnóstico Precoce , Feminino , Humanos , Lactente , Masculino , Síndrome , Bexiga Urinaria Neurogênica/diagnóstico , Bexiga Urinaria Neurogênica/fisiopatologia , Infecção por Zika virus/congênito , Infecção por Zika virus/virologia
3.
Reprod Biomed Online ; 37(6): 709-715, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30527061

RESUMO

Hysteroscopic septum resection in women with unfavourable reproductive and clinical outcomes has become common practice worldwide to improve reproductive results. No clear evidence on the possible advantages and drawbacks of this procedure has been published. In this opinion paper, based on a SWOT (strengths, weaknesses, opportunities, threats) analysis, the different aspects of this strategy are evaluated. Currently, no level 1 published evidence supports uterine resection in women with septate uterus. Clinical evidence from the studies analysed matches the more recent guidelines and suggests an improvement in reproductive outcomes after hysteroscopic resection of the septum, particularly in infertile women and women who have experienced recurrent miscarriages. In a patient with no history of infertility or prior pregnancy loss, it may be reasonable to consider septum incision after counselling about the potential risks and benefits of the procedure. Published clinical data in favour of the intervention, however, are based on studies with important methodological limitations. In this situation, the clinician and patient should reach an agreement together, based on the pros and cons of this intervention. Well-designed randomized controlled trials are required to confirm the clinical benefits and cost-effectiveness of this procedure.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/estatística & dados numéricos , Infertilidade Feminina/cirurgia , Útero/cirurgia , Aborto Habitual , Aborto Induzido , Adulto , Feminino , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Humanos , Histeroscopia , Guias de Prática Clínica como Assunto , Reprodução , Medicina Reprodutiva , Resultado do Tratamento , Útero/anormalidades
4.
Genet Mol Res ; 14(2): 5435-44, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-26125739

RESUMO

The increased incidence of fungal infections and the development of drug resistance have led to the search for microorganisms capable of producing bioactive metabolites with antifungal activity. Among these microorganisms, Streptomyces spp are distinguished mainly owing to their potential to secrete bioactive molecules. The aim of this study was to evaluate the production of secondary metabolites by Streptomyces sp TUR-10 against 12 fungal clinical isolates (yeast and filamentous fungi). In the preliminary screening, Streptomyces sp TUR-10 showed activity against 75% of the clinical isolates, and was selected for fermentation. In this assay, we tested three different media (MPE, M1, and ISP-4) for 96 h at pH 7.0 and 30°C for the production of bioactive metabolites. Increased production of bioactive compounds was observed when using the MPE medium for 48 h, with good activity against Candida pelliculosa. The minimum inhibitory concentration showed significant antifungal activity values ranging from 15.6 to 250 µg/mL. The actinobacterium was characterized by 16S rRNA analysis and the pattern suggested that the isolate studied belonged to the species Streptomyces ansochromogenes. The biotechnological potential of this strain was also demonstrated by the detection of the nrps and pks genes. These results indicate the production of secondary metabolites of biotechnological interest by actinobacteria from the rhizosphere, suggesting great potential for further research.


Assuntos
Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Metabolismo Secundário/genética , Streptomyces/química , Antifúngicos/química , Antifúngicos/isolamento & purificação , Candida/efeitos dos fármacos , Candida/patogenicidade , Fungos/patogenicidade , Humanos , Testes de Sensibilidade Microbiana , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/genética , Streptomyces/metabolismo
5.
J Fish Biol ; 83(2): 272-94, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23902306

RESUMO

Seven coastal fish species are newly reported for the remote north Atlantic archipelago of the Azores: Mediterranean sand eel Gymnammodytes cicerelus, bar jack Caranx ruber, two-banded seabream Diplodus vulgaris, bastard grunt Pomadasys incisus, unicorn leatherjacket filefish Aluterus scriptus and longspined porcupinefish Diodon holacanthus. The occurrence is also confirmed for 19 species that had been hitherto cited occasionally for the region, totalling a list of two elasmobranchs and 23 teleosts. Diplodus vulgaris, which appears to have recently colonized the islands, as well as roughtail stingray Dasyatis centroura and golden grey mullet Liza aurata, re-cited based on new records, are frequent or common coastal species in the Azores. The remaining 22 species, exceptional or rare in the region, are of tropical or subtropical affinity and find their northernmost distribution limit within the central and north-east Atlantic Ocean precisely in the Azores. This biogeographical pattern contrasts with that of the Azorean coastal fish community and suggests a tropicalization process in the region in line with previous findings of similar patterns across the north-east Atlantic Ocean and the Mediterranean Sea. These novel data from the most isolated archipelago of the North Atlantic Ocean, located in a biogeographic boundary area where colonization opportunities are reduced, reinforce the need for long-term monitoring programmes of coastal fish communities and, in particular, of indicator species groups to improve understanding of the effects of climate change on marine communities.


Assuntos
Biodiversidade , Mudança Climática , Peixes/classificação , Animais , Açores , Peixes/fisiologia , Filogenia , Filogeografia , Dinâmica Populacional
6.
Transfus Med ; 23(2): 87-93, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23406333

RESUMO

BACKGROUND: Changes that occur to red blood cells (RBCs) during routine blood bank storage include decreased deformability, increased haemolysis and oxidative damage. Oxidative injury to the RBC membrane and haemoglobin can affect changes in shape and deformability. Ascorbic acid (AA) is an antioxidant that maintains haemoglobin in a reduced state and minimises RBC oxidative injury. We hypothesised that AA would improve membrane fragility and decrease haemolysis during storage. METHODS: Whole blood derived, AS-5 preserved, pre-storage leucoreduced RBC units were exposed to either AA or saline control solutions. Several rheological and biochemical parameters were measured serially during storage, including RBC membrane mechanical fragility, percent haemolysis and methaemoglobin levels. RESULTS: AA exposure significantly reduced mechanical fragility and haemolysis over the entire storage period. The highest two concentrations of AA affected the greatest reductions in mechanical fragility and percent haemolysis. Addition of AA to the RBCs did not significantly alter their biochemical parameters compared to control RBCs incubated with saline. CONCLUSION: AA reduced RBC membrane fragility and decreased haemolysis during storage without adversely affecting other RBC biochemical parameters. The clinical significance of these findings needs to be determined.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Preservação de Sangue , Deformação Eritrocítica/efeitos dos fármacos , Deformação Eritrocítica/ética , Membrana Eritrocítica/metabolismo , Hemólise/efeitos dos fármacos , Adulto , Membrana Eritrocítica/química , Feminino , Hemoglobinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução/efeitos dos fármacos
7.
J Fish Biol ; 75(6): 1271-86, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20738614

RESUMO

Recruitment of the temperate reef fish Coris julis was studied across the Azores Archipelago (central North Atlantic), over four consecutive recruitment seasons and at three spatial scales: between islands (separated by 100s of km), sites within islands (separated by 10s of km) and transects within sites (separated by 10s of m). At the largest scale (i.e. between islands) spatial recruitment patterns were highly variable, suggesting the influence of stochastic processes. Recruitment was spatially consistent within islands, even though magnitude was unpredictable between years, indicating that processes at meso-scales are probably more deterministic. Recruits settled randomly at the transect scale, probably reflecting habitat homogeneity. It was proposed that large and island-scale patterns reflect larval availability, driven by physical and biological processes occurring in the plankton. No evidence was found for a density-dependent relationship between newly settled and 2 week settled C. julis nor between cumulative recruitment and young-of-the-year. It appears that adult density is limited by larval supply (pre-settlement regulation) at low recruitment sites, and determined by post-settlement, density-dependent processes at high recruitment sites. This work is one of few to investigate multiple spatial and temporal scales of recruitment for a coastal fish species inhabiting isolated, temperate oceanic islands and hence, provides a novel comparison to the many studies of recruitment on coral reefs and other, more connected systems.


Assuntos
Recifes de Corais , Perciformes/fisiologia , Animais , Oceano Atlântico , Açores , Densidade Demográfica , Dinâmica Populacional
8.
Cerebrovasc Dis ; 19(3): 152-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15644627

RESUMO

Factors influencing early hospital admission have been described for several stroke types but not for cerebral vein and dural sinus thrombosis (CVT). CVT is more difficult to diagnose than arterial stroke; delay in hospital admission may postpone CVT treatment. The purposes of this study were: (1) to describe the delay between the onset of symptoms and hospital admission of patients with CVT, and (2) to identify the variables that influence that delay. We registered the interval (days) between the onset of symptoms and hospital admission in 91 consecutive patients admitted to 20 Portuguese hospitals between June 1995 and June 1998. We also studied the impact of admission delay on treatments (prescription of anticoagulants and the number of days elapsed between the onset of symptoms and start of anticoagulation and admission). Median admission delay was 4 days. Twenty-two (25%) patients were admitted within 24 h. Two thirds of the patients were admitted within 7 days and 75% within 13 days. In multiple logistic regression analysis, admission within 24 h was positively associated with mental status disorder (delirium or abulia; OR = 4.59; 95% CI = 1.41-14.89) and negatively associated with headache (OR = 0.03; 95% CI = 0.00-0.32). Presentation as isolated intracranial hypertension was associated with admission delay of more than 4 days (OR = 2.63; 95% CI = 0.97-7.14). Papilloedema was associated with an admission delay of more than 13 days (OR = 4.69; 95% CI = 1.61-13.61). There was no association between admission delay and the proportion of anticoagulated patients. The interval between onset of symptoms and start of anticoagulation was shorter in patients admitted earlier (p = 0.0001, for either admission within 24 h, 4 or 13 days). There is a considerable delay until the clinical picture associated with CVT is recognised as justifying hospital admission, especially when patients present with symptoms identical to isolated intracranial hypertension syndrome.


Assuntos
Hospitalização/estatística & dados numéricos , Trombose Intracraniana/diagnóstico , Trombose dos Seios Intracranianos/diagnóstico , Anticoagulantes/uso terapêutico , Dura-Máter/irrigação sanguínea , Feminino , Humanos , Hipertensão Intracraniana/diagnóstico , Hipertensão Intracraniana/tratamento farmacológico , Hipertensão Intracraniana/epidemiologia , Trombose Intracraniana/tratamento farmacológico , Trombose Intracraniana/epidemiologia , Masculino , Pessoa de Meia-Idade , Admissão do Paciente/estatística & dados numéricos , Portugal/epidemiologia , Índice de Gravidade de Doença , Trombose dos Seios Intracranianos/tratamento farmacológico , Trombose dos Seios Intracranianos/epidemiologia , Fatores de Tempo
9.
J Assist Reprod Genet ; 21(6): 187-95, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15526973

RESUMO

PURPOSE: To study the correlation between the expression of integrin fractions and adhesion molecules on granulosa cells (GC) and follicular development. METHODS: GC and follicular fluid (FF) were obtained at oocyte retrieval for ICSI. Expression of adhesion molecules on GC was studied by flow cytometry. Statistics were evaluated using the Student t test and simple linear regression analysis. RESULTS: alpha5 integrin fraction was significantly (p < 0.01) higher, while alpha6 fraction and CD9 were significantly (p < 0.01 and p < 0.001, respectively) lower in GC from FF with metaphase II oocytes. A direct significant correlation was observed between FF progesterone and the alpha5 expression on GC (r = 0.54). In contrast, an inverse significant correlation was observed between FF progesterone level and the expression of alpha6 and CD9 (r = -0.40 and -0.41, respectively). CONCLUSIONS: The expression pattern for integrin fractions and adhesion molecules may be of predictive value in assessing the state of differentiation of the human follicle.


Assuntos
Líquido Folicular/química , Células da Granulosa/fisiologia , Integrinas/metabolismo , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Estradiol/análise , Feminino , Células da Granulosa/citologia , Humanos , Infertilidade Masculina , Masculino , Metáfase , Oócitos/citologia , Progesterona/análise , Esteroides/biossíntese , Testosterona/análise
10.
Cerebrovasc Dis ; 13(4): 272-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12011553

RESUMO

The purpose of this study was to analyze the long-term mortality, functional recovery and long-term complications of cerebral vein and dural sinus thrombosis (CVDST) admitted to Portuguese hospitals. A follow-up of symptomatic CVDST admitted to Portuguese hospitals since 1980 was performed. Fifty-one patients (retrospective cases) were re-evaluated during 1996; 91 consecutively admitted patients from 6/1995 to 6/1998 were followed up to 1999. In 1996, 4 (8%) of the retrospective cases had died (3 patients died in the acute phase), 4 (8%) could not be reached, 33 (64%) had recovered completely (Rankin 0 or 1) and 3 (6%) were dependent. The prospective cases had a mean follow-up of 1 year: 6 (7%) patients died in the acute phase, one (1%) died during follow-up, 75 (82%) recovered completely, and only 1 (1%) was dependent. For the prospective cases, worsening after admission (OR = 18.2; 95% CI = 2.9-112.4) and encephalopathy as the presenting syndrome (OR = 7.1; 95% CI = 1.2-40.9) predicted death or dependency, while absence of aphasia (OR 6.7, 95% CI = 1.6-33) and no worsening after admission (OR = 5.9; 95% CI = 1.6-20) predicted total recovery. During follow-up of the prospective cases, 4 (5%) patients had thrombotic events, 8 (10%) patients experienced seizures, 9 (11%) complained of severe headaches and 1 patient suffered severe visual loss. The long-term functional prognosis of patients with CVDST was fairly good with complete recovery in the majority of cases. However, these patients had a moderate risk of further thrombotic events and seizures.


Assuntos
Veias Cerebrais/patologia , Dura-Máter/irrigação sanguínea , Dura-Máter/patologia , Trombose Intracraniana/complicações , Trombose Intracraniana/diagnóstico , Trombose dos Seios Intracranianos/complicações , Trombose dos Seios Intracranianos/diagnóstico , Adulto , Veias Cerebrais/diagnóstico por imagem , Dura-Máter/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Trombose Intracraniana/mortalidade , Modelos Logísticos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Portugal , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Radiografia , Estudos Retrospectivos , Trombose dos Seios Intracranianos/mortalidade , Análise de Sobrevida , Tempo
11.
Hum Reprod ; 16(3): 534-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11228225

RESUMO

The aim of this study was to evaluate the chromatin status in different groups of patients. Five groups of men were selected: pre-vasectomy; male factor infertility; varicocele; immunological male infertility; and idiopathic infertility. Chromatin status was evaluated using flow cytometry after staining the DNA with the fluorochrome propidium iodide. Differences were observed in the state of sperm chromatin between the male factor and varicocele groups with respect to the others. These two groups presented poorer quality chromatin, as evidenced fundamentally by a lower degree of condensation. These deficiencies in chromatin status were usually accompanied by alterations in the other standard parameters of semen analysis. Individuals who are infertile due to male factor and those presenting varicocele have spermatozoa with less condensed chromatin which might, in part, explain their sterility.


Assuntos
Cromatina/fisiologia , Ejaculação , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Sêmen/citologia , Sêmen/fisiologia , Espermatozoides/fisiologia , Varicocele/genética , Humanos , Masculino , Varicocele/fisiopatologia
12.
Rev Port Cardiol ; 19(5): 588-606, 2000 May.
Artigo em Português | MEDLINE | ID: mdl-10916432

RESUMO

The optimal diagnostic and treatment strategies for unstable angina/non-Q-wave myocardial infarction patients will continue to be redefined as rapid progress is made in the understanding, and treatment of this syndrome. The recommendations presented here reflect, in part, discussions at the International Cardiology Forum in September 1998. Although areas of controversy remain, we have summarized major points on which a consensus could be reached and for which the weight of the clinical evidence supports a change in practice.


Assuntos
Angina Instável/diagnóstico , Angina Instável/tratamento farmacológico , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/tratamento farmacológico , Angina Instável/epidemiologia , Humanos , Infarto do Miocárdio/epidemiologia , Guias de Prática Clínica como Assunto , Fatores de Risco
16.
Rev Port Cardiol ; 18(11): 1019-21, 1999 Nov.
Artigo em Português | MEDLINE | ID: mdl-10608161

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the in-hospital and follow-up prognostic value of cardiac troponin I in patients admitted in the Coronary Care Unit and discharged with the diagnosis of unstable angina. POPULATION AND METHODS: 118 patients were admitted in the Coronary Care Unit, discharged with the diagnosis of unstable angina with a follow-up of 13.5 months. Cardiac Troponin I (cTnI) was measured on admission, 4 and 12 hours later. For the purposes of the study, we chose a cut-off value of 0.4 ng/mL as the minimal acceptable concentration of cTnI. The patients were divided in two groups: Group A (n = 82) if all measurements with cTnI < or = 0.4 ng/mL and Group B (n = 36) if any measurement with cTnI > 0.4 ng/mL. In both groups, multiple coronary events during hospitalisation and follow-up were evaluated: death; acute myocardial infarction; angina; hospitalisation; coronary surgery or angioplasty; and also the severity of coronary artery disease and the number of patients without coronary events. The results were compared by the Student's unpaired t-test and by chi-square test. RESULTS: Age, sex and vascular risk factors were similar in both groups. There was a statistically significant increase in angina and coronary surgery with increasing levels of cardiac troponin I (Group B) (13 vs 5, p < 0.0001), multiple vessel disease (16 vs 18, p < 0.0008) and myocardial infarction (12% vs 0%, p < 0.03). Sixty patients had no coronary events in Group A compared to thirteen in Group B (p < 0.0001). There were no significant differences between the groups with respect to hospitalisation and angioplasty (17% in Group B vs 7% in Group A) and death (3% vs 0%). CONCLUSIONS: In this population with unstable angina, cardiac troponin I level greater than 0.4 ng/mL measured in the 12 hours after admission provides useful prognostic information. It permits the early identification of patients with an increased risk of in-hospital and follow-up cardiac events and could be correlated with the severity of coronary artery disease.


Assuntos
Angina Instável/metabolismo , Miocárdio/química , Troponina I/análise , Feminino , Seguimentos , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
18.
Rev Port Cardiol ; 18(12): 1129-36, 1999 Dec.
Artigo em Português | MEDLINE | ID: mdl-10661020

RESUMO

Assays of serum enzymes, such as aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) and isoenzyme MB, are widely performed in the early phase of suspected ischemic myocardial injury. However, these enzymes are not restricted to cardiac muscle tissue and increases in their serum concentrations have been observed in non-cardiac conditions. The levels of CK, and especially those of the myocardial specific isoform (CK-MB), have served as essential components for clinical decision in emergency rooms for over 25 years. This standard diagnostic test is far from perfect in specificity and the time delay necessary for the detection of a rise in levels. The clinician needs specific and sensitive biological parameters that can be rapidly measured in serum immediately after ischemic damage. In the last years, several new serum markers of myocardial damage have been developed. Currently, an important place is reserved for some non-enzyme muscle constituents, such as myoglobin and troponin sub-units, which have better specificity and allow an earlier detection of myocardial damage. The immunoassay of human cardiac troponin is a specific and sensitive diagnostic method for acute and sub-acute myocardial damage. It is ideal for the detection of myocardial necrosis in complex clinical situations when the usual enzymatic markers may be ineffective. An important prognostic value of troponin levels, especially troponin T, is currently under investigation. Myoglobin is a protein with low molecular weight that is abnormally high in serum two hours after myocardial infarction. Despite their high sensitivity, the use of serum measurements in the emergency room is controversial because of their low specificity, requiring the exclusion of skeletal muscle damage. Sensitivity could be lost in patients with renal function damage. The measurement of CK-MB protein weight (CK-MBmass) is another marker that has been confirmed as more accurate than CK-MB activity assays, especially in patients presented within four hours after the onset of chest pain, but could be inaccurate in several circumstances. In this research article, the authors describe the most important parameters of enzymatic and non-enzymatic markers, the kinetics of serum release, the clinical applications and the problems.


Assuntos
Isquemia Miocárdica/sangue , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Creatina Quinase/sangue , Creatinina/sangue , Humanos , Isoenzimas , L-Lactato Desidrogenase/sangue , Mioglobina/sangue , Sensibilidade e Especificidade , Troponina/sangue
19.
Mol Cell Biol ; 19(1): 941-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9858618

RESUMO

Class II major histocompatibility (class II) genes are regulated in a B-cell-specific and gamma interferon-inducible fashion. The master switch for the expression of these genes is the class II transactivator (CIITA). In this report, we demonstrate that one of the functions of CIITA is to recruit the CREB binding protein (CBP) to class II promoters. Not only functional but also specific binding interactions between CIITA and CBP were demonstrated. Moreover, a dominant negative form of CBP decreased the activity of class II promoters and levels of class II determinants on the surface of cells. Finally, the inhibition of class II gene expression by the glucocorticoid hormone could be attributed to the squelching of CBP by the glucocorticoid receptor. We conclude that CBP, a histone acetyltransferase, plays an important role in the transcription of class II genes.


Assuntos
Genes MHC da Classe II , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Transcrição Gênica , Animais , Linfócitos B , Sítios de Ligação , Células COS , Proteína de Ligação a CREB , Linhagem Celular Transformada , Dexametasona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Humanos , Regiões Promotoras Genéticas , Transativadores/genética
20.
J Mol Biol ; 270(3): 336-45, 1997 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-9237901

RESUMO

Regulatory factors that bind to the X box 1 to 5 (RFX1 to RFX5) and p36 interact with the X box in major histocompatibility class II promoters. RFX1 and RFX5 bind to DNA as a homodimer (RFX1) and heterodimer with p36 (RFX5:p36, the RFX complex), respectively. In this study, we characterized the binding of RFX1 and the RFX complex to the X box in vivo, and evaluated contributions of other proteins that bind to flanking conserved upstream sequences (CUS: S, X, X2, and Y boxes) to these protein-DNA interactions. For this purpose, an intracellular DNA-binding assay was developed. Hybrid protein effectors between RFX1 and RFX5 and the activation domain of VP16 from the herpes simplex virus were co-expressed with plasmid targets, which contained the isolated X box, X box and selected flanking CUS, or the entire DRA promoter. Whereas RFX1 bound better to isolated X boxes, the Y box selected for the binding of the RFX complex and against the binding of RFX1 to the X box. With proper spacing, S and X boxes stabilized the binding of both RFX1 and the RFX complex. The X2 box did not contribute significantly to the binding of either RFX1 or the RFX complex to the X box. Thus, complex protein-protein and protein-DNA interactions dictate the binding of functionally relevant proteins to conserved upstream sequences which regulate class II transcription.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/genética , Genes MHC da Classe II/genética , Regiões Promotoras Genéticas/genética , Animais , Linfócitos B , Células COS , Linhagem Celular , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteína Vmw65 do Vírus do Herpes Simples/genética , Modelos Genéticos , Proteínas Recombinantes de Fusão
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