Interleukin-6 contributes to myocardial damage in pregnant rats with reduced uterine perfusion pressure

Preeclampsia is one of the most frequent and difficult illnesses in pregnancy, which jeopardizes both mother and fetus. There are several diagnostic criteria for preeclampsia. However, the preeclampsia-associated myocardial damage has not been described. In this study, we employed reduced uterine perfusion pressure (RUPP) to generate a rat model of preeclampsia for the evaluation of myocardial damage in late-gestation rats. The expressions of cardiac injury markers were analyzed by immunohistochemistry and ELISA. The arterial pressure and myocardial tissue velocities were also measured. The role of interleukin (IL)-6 in RUPP-associated myocardial damage was further explored. The results showed that RUPP rats had significant myocardial damage, as demonstrated by the high expressions of myoglobin, creatine kinase isoenzyme, cardiac troponin I, and brain natriuretic peptide. In addition, RUPP increased the mean arterial pressure and the early transmitral flow velocity to mitral annulus early diastolic velocity ratio (E/Ea). Furthermore, IL-6 deteriorated these abnormalities, whereas inhibition of IL-6 significantly relieved them. In conclusion, our study demonstrated that RUPP rats displayed myocardial damage in an IL-6-dependent manner.

Sinovite e tenossinovite no Brasil: uma análise dos benefícios auxílio-doença / Synovitis and tenosynovitis in Brazil: analysis of sickness benefit claims

OBJETIVO: Analisar os fatores pessoais associados à prevalência e duração dos benefícios auxílio-doença decorrentes de sinovite e tenossinovite (CID10 M65). MÉTODO: Estudo transversal referente aos benefícios auxílio-doença decorrentes de sinovite e tenossinovite concedidos pelo Instituto Nacional de Seguro Social aos empregados no Brasil em 2008. Dados sobre o ramo de atividade econômica (Classificação Nacional de Atividades Econômicas - CNAE divisão, classe), sexo, idade, espécie e duração dos benefícios foram coletados do Sistema Único de Benefícios. A população corresponde à média mensal dos vínculos empregatícios declarados ao Cadastro Nacional de Informações Sociais. RESULTADOS: Em 2008 foram concedidos 35.601 benefícios auxílio-doença decorrentes de sinovite e tenossinovite, com prevalência de 10,9/10.000 vínculos empregatícios. No conjunto dos benefícios auxílio-doença houve maior razão de prevalência (RP) acidentária (RP 1,2), sendo esta maior em mulheres (RP 3,3), e em trabalhadores com idade acima de 39 anos (RP 1,4). As CNAE 37-Esgoto (55,4) e 60-Atividade de rádio e TV (47,1) apresentaram as maiores prevalências, no entanto, 64-Atividade de serviços financeiros e 6422-Bancos múltiplos caracterizaram mais acidentes de trabalho (RP 3,2 e 3,8, respectivamente) e maior duração (70 e 73 dias, respectivamente). A maior duração de benefício ocorreu entre trabalhadores com idade superior a 39 anos. Tanto a CNAE-divisão 60-Atividade de rádio e TV, quanto a CNAE-classe 6010-Atividade de rádio apresentaram elevadas razões de feminilidade (RP 8,1 e 10,8, respectivamente). CONCLUSÃO: A incapacidade para o trabalho por sinovite e tenossinovite apresenta associação tanto da prevalência quanto da duração com o ramo de atividade, sexo, idade e espécie de benefício (previdenciário/acidentário). .

OBJECTIVE: To analyse the personal and occupational factors associated with the prevalence and duration of sickness benefit claims due to synovitis and tenosynovitis (CID10 M65). METHODS: Cross-sectional study regarding sickness benefit claims due to synovitis and tenosynovitis granted to employees by National Institute of Social Security in Brazil in 2008. Data on economic activity (Economic Activities National Classification - CNAE division, class), sex, age, type and duration of benefits were collected from the Unified Benefit System. The study's population consists of the average monthly employment contracts declared to the National Register of Social Information. RESULTS: In 2008, 35,601 employees were granted sickness benefits due to synovitis and tenosynovitis, with a prevalence of 10.9/10,000 employments. Sickness benefits showed higher prevalence rates (PR) for work-related claims (PR 1,2), mostly made by females (PR 3.3) and by workers older than 39 years (PR 1,4). The CNAE 37-Sewage (55.4) and 60-Broadcasting Activity (47.1) had the highest overall prevalence. However, the 64-Financial service activities, except insurance and pension funding and 6422-Multiple banks with commercial service had the highest rates of work-related claims (RP 3.2 and 3.8, respectively), and the longer duration (70 and 73 days, respectively). Workers older than 39 years had the highest durations of work disability claims. Both the CNAE-division 60-Broadcasting Activity, and the CNAE-class 6010-Radio showed a high activity ratio of females (PR 8.1 and 10.8, respectively). CONCLUSION: The work disability due to synovitis and tenosynovitis presents prevalence and duration associated with economic activity, sex, age and kind of benefit (non work-related and work-related claims). .

Neonatal hyper- and hypothyroidism alter the myoglobin gene expression program in adulthood

Myoglobin acts as an oxygen store and a reactive oxygen species acceptor in muscles. We examined myoglobin mRNA in rat cardiac ventricle and skeletal muscles during the first 42 days of life and the impact of transient neonatal hypo- and hyperthyroidism on the myoglobin gene expression pattern. Cardiac ventricle and skeletal muscles of Wistar rats at 7-42 days of life were quickly removed, and myoglobin mRNA was determined by Northern blot analysis. Rats were treated with propylthiouracil (5-10 mg/100 g) and triiodothyronine (0.5-50 µg/100 g) for 5, 15, or 30 days after birth to induce hypo- and hyperthyroidism and euthanized either just after treatment or at 90 days. During postnatal (P) days 7-28, the ventricle myoglobin mRNA remained unchanged, but it gradually increased in skeletal muscle (12-fold). Triiodothyronine treatment, from days P0-P5, increased the skeletal muscle myoglobin mRNA 1.5- to 4.5-fold; a 2.5-fold increase was observed in ventricle muscle, but only when triiodothyronine treatment was extended to day P15. Conversely, hypothyroidism at P5 markedly decreased (60%) ventricular myoglobin mRNA. Moreover, transient hyperthyroidism in the neonatal period increased ventricle myoglobin mRNA (2-fold), and decreased heart rate (5%), fast muscle myoglobin mRNA (30%) and body weight (20%) in adulthood. Transient hypothyroidism in the neonatal period also permanently decreased fast muscle myoglobin mRNA (30%) and body weight (14%). These results indicated that changes in triiodothyronine supply in the neonatal period alter the myoglobin expression program in ventricle and skeletal muscle, leading to specific physiological repercussions and alterations in other parameters in adulthood.

Effect of triiodothyronine on the maxilla and masseter muscles of the rat stomatognathic system

The maxilla and masseter muscles are components of the stomatognathic system involved in chewing, which is frequently affected by physical forces such as gravity, and by dental, orthodontic and orthopedic procedures. Thyroid hormones (TH) are known to regulate the expression of genes that control bone mass and the oxidative properties of muscles; however, little is known about the effects of TH on the stomatognathic system. This study investigated this issue by evaluating: i) osteoprotegerin (OPG) and osteopontine (OPN) mRNA expression in the maxilla and ii) myoglobin (Mb) mRNA and protein expression, as well as fiber composition of the masseter. Male Wistar rats (~250 g) were divided into thyroidectomized (Tx) and sham-operated (SO) groups (N = 24/group) treated with T3 or saline (0.9 percent) for 15 days. Thyroidectomy increased OPG (~40 percent) and OPN (~75 percent) mRNA expression, while T3 treatment reduced OPG (~40 percent) and OPN (~75 percent) in Tx, and both (~50 percent) in SO rats. Masseter Mb mRNA expression and fiber type composition remained unchanged, despite the induction of hypo- and hyperthyroidism. However, Mb content was decreased in Tx rats even after T3 treatment. Since OPG and OPN are key proteins involved in the osteoclastogenesis inhibition and bone mineralization, respectively, and that Mb functions as a muscle store of O2 allowing muscles to be more resistant to fatigue, the present data indicate that TH also interfere with maxilla remodeling and the oxidative properties of the masseter, influencing the function of the stomatognathic system, which may require attention during dental, orthodontic and orthopedic procedures in patients with thyroid diseases.

Oxidation of oxymyoglobin by poplar plastocyanins a and b.

Oxidation of oxymyoglobin [MbO2 (Fe2+)] by isoplastocyanins a (PCa) and b (PCb) was experimentally investigated and the corresponding redox reaction was modeled using the physicochemical parameters of the isoforms to study the effect of the dimorphism. The kinetic curve of oxidation of MbO2 (Fe2+) by oxidized PCa [PCa(Cu2+)] and PCb [PCb(Cu2+)] and the pH-dependence of the rate constant k1 were determined. In the range of pH 4.8-9.0, PCb reacts with higher k1, compared with PCa. For example, at pH 7.0, k1(PCb) = 4 × 102 M-1s-1, whereas k1(PCa) = 2 × 102 M-1s-1. The observed values of ΔE0 for the reaction pairs Mb-PCa and Mb-PCb were -304 mV and -319 mV, respectively. The effect of the ionic strength (µ) on the rate of the electron transfer was also studied. It was found that: (i) the net charge Z1 of PCa and PCb fully corresponds to that calculated by their primary structures and Z2 of Mb corresponds to that calculated by its titration curve; (ii) the ln k as function of √¯µ was similar for both PCa and PCb; (iii) the curve of the reaction PCb Mb (pH 7.0) was shifted towards higher values of k, in agreement with the larger net negative charge of PCb; and (iv) the character of the electrostatic interactions remained unchanged by a replacement of PCa by PCb and by the change of pH from 7.0 to 4.8.

Relationship between the degradation of myoglobin and postmortem interval / 法医学杂志

OBJECTIVE@#To observe the degradation of myoglobin in skeletal and cardiac muscles after death and to explore its usefulness in estimation of postmortem interval.@*METHODS@#Human skeletal and cardiac muscles were collected at 0, 4, 8, 12, 24, 36, 48, 60, and 72 hours after death and stored at 25 degrees C. The protein was extracted and examined and analyzed by Western blot and imaging technique.@*RESULTS@#Myoglobin showed a continuously postmortem degradation in both skeletal and cardiac muscles. There was no observed difference in degradation between the two tissues.@*CONCLUSION@#Changes in myoglobin degradation could be a useful parameter for estimation of the postmortem interval.

Immunohistochemical observation of heart-type fatty acid binding-protein in early myocardial ischemia / 法医学杂志

OBJECTIVE@#The sensitivity of heart-type fatty acid binding-protein (H-FABP) in the postmortem diagnosis of myocardial ischemia was explored.@*METHODS@#The changes of H-FABP staining in normal, infarcted and suspected ischemia of myocardial cells were studied by immunohistochemistry.@*RESULTS@#There was no depletion in normal control group, and obvious depletion was observed in myocardial infarcted group. Among 9 suspected myocardial ischemia group, 3 cases showed obvious depletion and 3 cases showed vague depletion for H-FABP, there were obvious depletion of Mb in 4 suspected myocardial ischemia cases and vague depletion in 2 cases for Mb. It is indicated that H-FABP can be used to diagnose early myocardial ischemia.@*CONCLUSION@#H-FABP is quite sensitive and useful for the diagnosis of early myocardial ischemia.

Morphological changes of tissues after extensive soft tissue injury / 法医学杂志

OBJECTIVE@#To study the pathological morphological changes for diagnosing the cause of death of extensive soft tissue injury or crush syndrome.@*METHODS@#The tissues were stained by HE and IHC.@*RESULTS@#(1) The Mb positive rate was 60%, 75%, 95% respectively. (2) Both the HSP70 positive rate of hearts and brains were 90%.@*CONCLUSION@#(1) The animal model of broad soft tissue injury was established. (2) Accumulated the pathological morphological data for diagnosing the cause of death of extensive soft tissue injury or crush syndrome.

New cardiac markers: selecting the best tools for reaching an accurate diagnosis and determining the patient's prognosis.

Many new cardiac markers have evolved over the past one decade. The role of existing cardiac markers is being redefined. Cardiac markers of late have become not only an important diagnostic tool, but also their prognostic significance is slowly being recognised. They have also become a deciding factor on the need of instituting aggressive management protocols like percutaneous coronary interventions. This article takes a latest updated look on these aspects of serum cardiac markers.

Comparative studies on the interaction of protoporphyrin with hemoglobin and myoglobin.

The binding parameters of protoporphyrin IX (PPIX) with hemoglobin (Hb) were studied spectrofluorimetrically and the results were compared with those of PPIX interacting with myoglobin (Mb). Two concentration ranges of PPIX (0.3 microM-1.5 microM and 1.5 microM-3.0 microM) were used. For both hemoglobin and myoglobin, the binding affinity constant (K) decreased while the number of binding sites (p) increased as the concentration range of PPIX increased. The interactions occurred in non-cooperative mode. Over a particular PPIX range, the interaction of PPIX with hemoglobin decreased significantly with increasing NaCl molarity indicating a trend in electrostatic interaction, whereas PPIX binding with myoglobin did not change significantly indicating mostly non-electrostatic mode of interaction. Total bound charge (z psi) decreased significantly with increased PPIX concentration range in case of hemoglobin-PPIX interaction, but remained almost same in case of myoglobin-PPIX interactions. Thermodynamic analysis revealed that binding of PPIX to hemoglobin was mostly electrostatic at lower concentration range of PPIX but became less electrostatic at higher concentration range and myoglobin-PPIX interaction, predominantly hydrophobic in nature, became more hydrophobic with increased range of PPIX concentration. The difference in binding modality between PPIX-Hb and PPIX-Mb has been discussed in relation to the state of aggregation of porphyrin as well as the subunit interaction property present and absent in hemoglobin and myoglobin, respectively.

Spectrophotometric measurements on verdo-myoglobin: relevance to the oxidation of ferri-myoglobin by chlorite ion.

Spectrophotometric observations on verdo-myoglobin, reconstituted from apomyoglobin and verdo-heme and its oxidation products, are described. Relevance of these results to the oxidation of ferri-myoglobin by chlorite ion is also discussed.