RESUMO
Insulinoma is the most common cause of endogenous hyperinsulinemic hypoglycemia in adults. An alternate etiology, non-insulinoma pancreatogenous hypoglycemia (NIPH), is rare. Clinically, NIPH is characterized by postprandial hyperinsulinemic hypoglycemia, negative 72-h fasts, negative preoperative localization studies for insulinoma and positive selective arterial calcium infusion tests. Histologically, diffuse islet hyperplasia with increased number and size of islet cells is present and confirms the diagnosis. Differentiating NIPH from occult insulinoma preoperatively is challenging. Partial pancreatectomy is the procedure of choice; however, recurrence of symptoms, although less debilitating, occurs commonly. Medical management with diazoxide, verapamil and octreotide can be used for persistent symptoms. Ultimately, near-total or total pancreatectomy may be necessary. We report a case of a 67-year-old male with hypoglycemia in whom preoperative workup, including computerized tomography abdomen, suggested insulinoma, but whose final diagnosis on pathology was NIPH instead.
RESUMO
BACKGROUND: HbA1c is used in the diagnosis and monitoring of diabetes mellitus (DM). Interference from hemoglobin variants is a well-described phenomenon, particularly with HPLC-based methods. While immunoassays may generate more reliable HbA1c results in the presence of some variants, these methods are susceptible to negative interference from high concentrations of HbF. We report a case where an accurate HbA1c result could not be obtained by any available method due to the presence of a compound hemoglobinopathy. METHODS: HbA1c was measured by HPLC, immunoassay, and capillary electrophoresis. Hemoglobinopathy investigation consisted of a CBC, hemoglobin fractionation by HPLC and electrophoresis, and molecular analysis. RESULTS: HbA1c analysis by HPLC and capillary electrophoresis gave no result. Analysis by immunoassay yielded HbA1c results of 5.9% (Siemens DCA 2000+) and 5.1% (Roche Integra), which were inconsistent with other markers of glycemic control. Hemoglobinopathy investigation showed HbC with the hereditary persistence of fetal hemoglobin-2 Ghana deletion. CONCLUSION: Reliable HbA1c results may be unobtainable in the presence of some hemoglobinopathies. HPLC and capillary electrophoresis alerted the laboratory to the presence of an unusual hemoglobinopathy. Immunoassays generated falsely low results without warning, which could lead to missed diagnoses and under treatment of patients with DM.
Assuntos
Hemoglobina Fetal/análise , Hemoglobinas Glicadas/análise , Hemoglobina C/análise , Hemoglobinopatias/sangue , Adulto , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Eletroforese Capilar , Hemoglobina Fetal/genética , Hemoglobina C/genética , Hemoglobinopatias/genética , Humanos , Imunoensaio , Masculino , Reação em Cadeia da PolimeraseRESUMO
Fluorescent proteins exhibit a very diverse range of photochemical behaviour, from efficient fluorescence through photochromism to photochemical reactivity. Remarkably this diverse behaviour arises from chromophores which have very similar structures. Here we describe measurements and modelling of the excited state dynamics in the chromophores of GFP (HBDI) and the kindling fluorescent protein, KFP (FHBMI). The methods are ultrafast fluorescence spectroscopy with sub 50 fs time resolution and the modelling is based on the Smoluchowski equation. The excited state decays of both chromophores are very fast, longer for their anions than for the neutral form and independent of wavelength. Detailed studies show the mean fluorescence wavelength to be independent of time. The excited state decay times are also observed to be a very weak function of solvent polarity and viscosity. These results are modelled utilising recently calculated potential energy surfaces for the ground and excited states as a function of the twist coordinates about the two bridging bonds of the chromophore. For FHBMI and the scarce data on the neutral HBDI the calculations are not successful suggesting the need for refinement of these potential energy surfaces. For HBDI in methanol the simulation is successful provided a strong dependence of the radiationless decay rate on the coordinate is assumed. Such dependence should be included in future calculations of excited state dynamics. When the simulations are extended to more viscous solvents they fail to reproduce the observed weak viscosity dependence. The implications of these results for the nature of the coordinate leading to radiationless decay in the chromophore and for the photodynamics of fluorescent proteins are discussed.
Assuntos
Compostos Cromogênicos/química , Proteínas de Fluorescência Verde/química , Proteínas Luminescentes/química , Fluorescência , Simulação de Dinâmica Molecular , Espectrometria de Fluorescência , Fatores de TempoRESUMO
Cis-trans photoisomerization is proposed as a key process in the photoswitching of some photoactivatable fluorescent proteins. Here we present ultrafast fluorescence measurements of the model GFP chromophore (HBDI) in the cis state and in a mixture of the cis and trans states. Our results demonstrate that the mean lifetimes of the cis and trans states are remarkably similar. Therefore, the specific isomer of the chromophore cannot be solely responsible for the different photophysics of the bright and dark states of photoactive proteins, which must therefore be due to differential interactions between the different isomers of the chromophore and the protein.
RESUMO
BACKGROUND: The Clinical Pulmonary Infection Score (CPIS) has been used in the intensive care unit (ICU) as a decision tool for initiation of antibiotics in suspected pneumonia and also for discontinuing antibiotics if the CPIS score is Assuntos
Antibacterianos/uso terapêutico
, Infecção Hospitalar/tratamento farmacológico
, Unidades de Terapia Intensiva
, Pneumonia/tratamento farmacológico
, Índice de Gravidade de Doença
, Adolescente
, Adulto
, Idoso
, Idoso de 80 Anos ou mais
, Uso de Medicamentos
, Feminino
, Hospitais com mais de 500 Leitos
, Hospitais Universitários
, Humanos
, Masculino
, Pessoa de Meia-Idade
, Pneumonia Bacteriana/tratamento farmacológico
, Pneumonia Associada à Ventilação Mecânica/tratamento farmacológico
, Guias de Prática Clínica como Assunto
, Estudos Prospectivos
, Curva ROC