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1.
Psychol Health Med ; 16(3): 304-12, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21491338

RESUMO

The physical disabilities associated with scleroderma are well known but the psychological impact of the condition has received less attention. Few studies have examined appearance related issues, most notably of the face. The aim of this study is to evaluate the psychological impact of facial, aesthetic and functional changes in scleroderma. One hundred seventy-one patients with a clinical diagnosis of scleroderma were recruited into the study. Digital photographs were objectively graded into groups based on severity of disfigurement as judged by an observer. Facial movement was recorded using a modified House-Brackmann Grading Scale. Psychological evaluation comprised the Derriford Appearance Scale short-form (DAS), the Noticeability and Worry score and the Hospital Anxiety and Depression Scale (HADS). Severity of disfigurement predicted decreased mouth opening, the extent to which participants judged their appearance as noticeable to others, and the level of appearance-related concern as measured by the DAS24. There was an inverse relationship with age. Facial changes were ranked as the most worrying aspect of the condition. This study shows facial disfigurement impacts on patient with scleroderma independent of functional changes related to systemic disease. The major difficulty is with the perceived noticeably of the condition to other people and the resulting self-consciousness in social encounters.


Assuntos
Face/fisiopatologia , Esclerodermia Limitada/psicologia , Estresse Psicológico/epidemiologia , Face/patologia , Humanos , Londres/epidemiologia , Pessoa de Meia-Idade , Esclerodermia Limitada/complicações , Esclerodermia Limitada/patologia , Inquéritos e Questionários
2.
Water Res ; 43(5): 1265-72, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19167018

RESUMO

Experiments were carried out to establish whether nitrous oxide (N2O) could be used as a non-invasive early warning indicator for nitrification failure. Eight experiments were undertaken; duplicate shocks DO depletion, influent ammonia increases, allylthiourea (ATU) shocks and sodium azide (NaN3) shocks were conducted on a pilot-scale activated sludge plant which consisted of a 315 L completely mixed aeration tank and 100 L clarifier. The process performed well during pre-shock stable operation; ammonia removals were up to 97.8% and N2O emissions were of low variability (<0.5 ppm). However, toxic shock loads produced an N2O response of a rise in off-gas concentrations ranging from 16.5 to 186.3 ppm, followed by a lag-time ranging from 3 to 5 h ((0.43-0.71) x HRT) of increased NH3-N and/or NO2(-) in the effluent ranging from 3.4 to 41.2 mg L(-1). It is this lag-time that provides the early warning for process failure, thus mitigating action can be taken to avoid nitrogen contamination of receiving waters.


Assuntos
Nitrogênio/metabolismo , Óxido Nitroso/análise , Esgotos , Amônia/metabolismo , Oxigênio/metabolismo , Projetos Piloto , Fatores de Tempo
3.
Genetika ; 45(12): 1600-8, 2009 Dec.
Artigo em Russo | MEDLINE | ID: mdl-20198970

RESUMO

Polymorphism and differentiation of the chromosome banding sequence pools and genomic DNA were studied in three natural populations of Chironomus entis from Europe and North America. These populations showed a moderate level of chromosome polymorphism and high RAPD polymorphism of genomic DNA. The Palearctic and Nearctic populations of this species did not differ significantly in the levels of chromosome and genomic DNA polymorphism. Estimation of the cytogenetic (GDcg) and genetic (GD(DNA)) distances between these C. entis populations showed that their chromosome banding sequence pools and cytogenetic structures are differentiated to a greater extent than genomic DNA. The values of cytogenetic and genetic distances between the Palearctic and Nearctic populations of C. entis are higher than the values of the corresponding distances between the Nearctic populations, but they do not reach the level of divergence between species.


Assuntos
Chironomidae/genética , Cromossomos/genética , DNA/genética , Genoma/fisiologia , Polimorfismo Genético/fisiologia , Animais , Bandeamento Cromossômico , Europa (Continente) , América do Norte , Técnica de Amplificação ao Acaso de DNA Polimórfico
4.
Water Sci Technol ; 52(8): 249-56, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16312974

RESUMO

Experiments were conducted in order to establish whether N2O could be used to predict nitrification failure (through non-invasive means). Previous research had shown a strong correlation between N2O gas and NH3 in the effluent, giving rise to the possibility N2O can be used as an indicator for failure in the nitrification process. Two pilot-scale activated sludge plants were used, each with two lanes. The smaller consisted of a 601 aeration tank and a 201 clarifier; the larger pilot plant had an aeration tank of 3151 and a clarifier of 1001. The small pilot plant experiments showed that N2O gas was given off almost immediately from O2 deprivation/NH3 shock loads, but did not follow the expected trend of the time lag of NH3 in the effluent. This led to further investigation in the hydrodynamics and mixing characteristics of aeration basins, where a second larger pilot plant was used. Further experiments were conducted of high NH3 loadings and O2 deprivation, showed that work of was reproducible. However, it was also shown that with partial nitrification failure, a different N2O response of a continual rise was observed.


Assuntos
Bactérias/metabolismo , Óxido Nitroso/metabolismo , Esgotos/análise , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Amônia/metabolismo , Óxido Nitroso/análise , Esgotos/microbiologia , Fatores de Tempo , Eliminação de Resíduos Líquidos/instrumentação , Purificação da Água/instrumentação
5.
J Econ Entomol ; 94(6): 1471-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11777051

RESUMO

Insects in Kentucky bluegrass seed production fields in Oregon, Idaho, and Washington were sampled just before harvest and their association with ergot conidia of Claviceps purpurea Fr. (Tul.) was evaluated during 1996-1998. A diversity of insects was observed at all three locations. The most abundant beneficial insects collected with sweep nets were Nysium spp., Nabis spp., ichneumonid wasps, and Hippodamia spp. The cranberry girdler, Chrysoteuchia topiaria (Zeller), was the only important pest on grass seed collected by sweep net. Numbers of aphids such as Sitobion avenae (F.), cicadellids and thrips such as Anaphothrips spp. and Aptinothrips spp. that were collected with all aphid sampler were below economic thresholds. Other insect groups occurred in low numbers. Noctuid moths collected in universal blacklight traps included nine species of cutworms and armyworms. Protogrotis obscura (B. & McD.) was the most common cutworm species and was present in all fields. The moth Chortodes rufostrigata (Pack.) previously reported only from wet meadows in northeast and south central Oregon was found in Kentucky bluegrass fields in central Oregon, suggesting that irrigated Kentucky bluegrass seed production fields may simulate a montane meadow habitat. Conidia of C. purpurea were found on a diversity of insects, including moths, flies, leafhoppers, and thrips. Up to 100% of moths and 75% of flies collected from some fields carried conidia of C. purpurea. No correlation between ergot honeydew present in a field and number of insects with conidia of C. purpurea was detected.


Assuntos
Claviceps , Insetos Vetores/microbiologia , Insetos/microbiologia , Poaceae , Animais , Kentucky , Doenças das Plantas , Sementes
6.
Biotechnol Bioeng ; 69(1): 101-6, 2000 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10820336

RESUMO

A simple, scalable method for purification of plasmid DNA is described. The method includes modification of the classical alkaline-lysis-based plasmid extraction method by extending the solubilization step from less than 30 min to 24 h. The extraction is followed by the novel use of tangential flow filtration (TFF) for purification of the remaining contaminants. The method does not include the use of any organic solvents, RNase, high-speed centrifugation, or column chromatography steps. The method typically yields 15 to 20 mg of plasmid DNA per liter of bacterial culture and results in removal of >99% of RNA and >95% of the protein that remains after the modified alkaline lysis procedure. The procedure has been demonstrated to be effective in the isolation of seven different plasmids. Plasmids isolated using this method had comparable transfection capability relative to plasmid isolated using a classical, cesium chloride gradient-based method.


Assuntos
DNA/isolamento & purificação , Filtração/métodos , Plasmídeos , Linhagem Celular , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Fator VIII/genética , Fator VIII/metabolismo , Humanos , Transfecção
8.
Circ Res ; 64(3): 616-28, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2917384

RESUMO

Previous studies have revealed that the regional accumulation of ischemic metabolites including hydrogen ion (H+) and PCO2 diminish after repeated occlusions. We postulated that this diminution reflects a blunted metabolic response that is related to the severity of ischemic injury and, hence, may be most pronounced in subendocardial (ENDO) regions. To investigate this hypothesis, the left anterior descending coronary artery was serially occluded three times in 51 dogs for a period of either 3 minutes (n = 15), 5 minutes (n = 18), or 15 minutes (n = 18). Each occlusion was separated by 45 minutes of reperfusion. Myocardial [H+] was measured in the endomyocardium and in the epimyocardium of the ischemic anterior wall by use of miniature pH glass electrodes. Accumulation of H+ during occlusion (delta [H+]) in the ENDO region was significantly less during the second occlusion when compared with the first occlusion (3-minute occlusions: 28.2 +/- 3.7 nM/l vs. 39.4 +/- 5.4 nM/l, p less than 0.002; 5-minute occlusions: 49.8 +/- 5.0 nM/l vs. 72.1 +/- 6.5 nM/l, p less than 0.0002; 15-minute occlusions: 132.3 +/- 14.6 nM/l vs. 225.6 +/- 27.7 nM/l, p less than 0.0003). A similar trend was noted for delta [H+] in the subepicardial (EPI) regions. During occlusion, the rise in [H+] occurred sooner, and delta [H+] was consistently greater in the ENDO when compared with the EPI regions (p less than 0.05). Regional myocardial blood flow did not change during the three occlusions, indicating that the diminution in H+ accumulation stemmed from a decrease in H+ production and not from an increase in collateral flow. The decrement in H+ accumulation between the first and second occlusions (delta [H+]1-delta [H+]2) 1) was greater in the ENDO than in the EPI regions (p less than 0.05); 2) correlated with the duration of occlusion (ENDO: r = 0.66, p less than 0.001; EPI: r = 0.82, p less than 0.0001); and 3) was related to the impairment of anterior wall systolic shortening after the first reperfusion period. These findings suggest that the diminution in H+ production that follows serial coronary occlusions reflects a blunted metabolic response that is related to both the duration of ischemia and the degree of systolic dysfunction. Moreover, though attenuation of ischemic metabolite production occurs transmurally, it is most pronounced in the deep ENDO regions.


Assuntos
Doença das Coronárias/metabolismo , Hidrogênio/metabolismo , Miocárdio/metabolismo , Animais , Velocidade do Fluxo Sanguíneo , Circulação Coronária , Doença das Coronárias/fisiopatologia , Cães , Endocárdio/metabolismo , Vidro , Concentração de Íons de Hidrogênio , Microeletrodos , Recidiva , Sístole , Fatores de Tempo
9.
Ann Plast Surg ; 22(2): 108-16, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2735706

RESUMO

Clinical measures often fail to detect early tissue ischemia in inadequately perfused flaps. This study investigates the application of a new pH electrode system to monitor tissue metabolism continuously in porcine and human musculocutaneous flaps. Bilateral rectus abdominis flaps based on the deep inferior epigastric pedicle were elevated in eight mixed-breed pigs. Tissue pH was measured in the subcutaneous and muscular layers with miniature glass-tip electrodes. The deep inferior epigastric artery and vein were serially and then concomitantly occluded for 20-minute periods. The decrease in tissue pH was greater following either arterial or pedicle occlusion (each 0.21 +/- 0.03 units) when compared with venous occlusion (0.10 +/- 0.02 units; p less than 0.02). Changes in muscle and subcutaneous hydrogen ion concentration were similar during arterial and venous occlusions (probability not significant). Measurement of subcutaneous pH appears to be a reliable experimental and clinical physiological tool for detecting early tissue ischemia in reconstructive flaps.


Assuntos
Músculos/fisiologia , Fenômenos Fisiológicos da Pele , Retalhos Cirúrgicos , Animais , Artérias/fisiologia , Constrição , Humanos , Concentração de Íons de Hidrogênio , Músculos/irrigação sanguínea , Pele/irrigação sanguínea , Suínos , Veias/fisiologia
10.
Ann Thorac Surg ; 45(1): 75-81, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3337581

RESUMO

Regional differences in myocardial acid production have not been characterized during administration of either asanguineous or sanguineous cardioplegia. To investigate this, miniature glass pH electrodes were placed in the right ventricular (RV) myocardium, the left ventricular subendocardial (LV endo) region, and the subepicardial (LV epi) region in a canine model. Multiple doses of either blood cardioplegia (Group 1; N = 11) or crystalloid cardioplegia (Group 2; N = 11) were administered during 4 hours of aortic cross-clamping. The accumulation of hydrogen ions during the cross-clamp period was greater in Group 2 than Group 1 in the LV endo region (629 +/- 79 nm/L versus 66 +/- 31 nm/L; p less than 0.001), the LV epi region (623 +/- 66 nm/L versus 72 +/- 32 nm/L; p less than 0.001), and the RV myocardium (814 +/- 296 nm/L versus 150 +/- 54 nm/L; p less than 0.05). Within each group, the time course of myocardial pH and the accumulation of hydrogen ions did not differ among the LV endo region, LV epi region, and the RV myocardium (p = not significant). These data indicate that transmural and interventricular differences in myocardial pH and hydrogen ion accumulation are not produced in the vented, arrested canine heart. In addition, when compared with asanguineous cardioplegia, blood cardioplegia globally and transmurally reduces acid accumulation during ischemic arrest.


Assuntos
Acidose/metabolismo , Sangue , Soluções Cardioplégicas/farmacologia , Doença das Coronárias/metabolismo , Parada Cardíaca Induzida , Miocárdio/metabolismo , Compostos de Potássio , Acidose/etiologia , Animais , Cães , Feminino , Parada Cardíaca Induzida/efeitos adversos , Concentração de Íons de Hidrogênio , Masculino , Potássio/farmacologia
11.
J Thorac Cardiovasc Surg ; 93(5): 741-54, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-2952840

RESUMO

To characterize the ultrastructural and metabolic changes occurring in the hypertrophied ventricle during cardiac operations in man, we studied 36 patients with valvular heart disease undergoing valve replacement, during which multiple doses of cold potassium cardioplegic solution were administered (Group I). Each patient had substantial ventricular hypertrophy according to measurements made of left ventricular mass, with a mean of 232.1 +/- 19.8 gm/m2 (normal: 92 +/- 16 gm/m2). Serial biopsy specimens were obtained from the left ventricular apex at the initiation of bypass, during the cross-clamp interval, and during reperfusion. Each specimen was scored from 0 to 4 according to ischemic changes in nuclear chromatin, mitochondrial swelling, myofibrillar edema, glycogen depletion, and overall cell morphology. Myocardial pH and temperature were measured continuously in the left ventricular free wall. During the cross-clamp period, ischemic injury was evidenced by changes in nuclear chromatin (0.38 +/- 0.10 to 1.25 +/- 0.21, p less than 0.0001), intracellular edema (0.43 +/- 0.06 to 0.97 +/- 0.14, p less than 0.002), overall cell morphology (0.37 +/- 0.06 to 0.97 +/- 0.14, p less than 0.001), and mitochondria (0.10 +/- 0.05 to 0.19 +/- 0.07, p less than 0.0001). During reperfusion, mitochondrial swelling increased further (0.19 +/- 0.07 to 0.35 +/- 0.08, p less than 0.0001) and glycogen stores were depleted (0.63 +/- 0.13 to 0.96 +/- 0.17, p less than 0.02), while the other structures remained unchanged. Myocardial pH declined during ischemic arrest from 6.89 +/- 0.04 to 6.40 +/- 0.04 (p less than 0.001). The changes in myocardial pH in Group I were compared to changes in myocardial pH in 10 patients (Group II) with no left ventricular hypertrophy undergoing isolated coronary bypass graft operations with the same protective techniques. In contrast to Group I, myocardial pH did not fall in Group II during ischemic arrest (6.98 +/- 0.06 to 6.94 +/- 0.05, p = not significant). Thus, with the use of current myocardial protective techniques, ultrastructural and metabolic changes indicative of ischemia are produced in the hypertrophied myocardium. The structural alterations consist of changes in nuclear chromatin and intracellular edema during the ischemic phase and by mitochondrial swelling during reperfusion.


Assuntos
Cardiomegalia/patologia , Doenças das Valvas Cardíacas/cirurgia , Miocárdio/ultraestrutura , Adulto , Idoso , Cardiomegalia/metabolismo , Cardiomegalia/cirurgia , Ponte de Artéria Coronária , Parada Cardíaca Induzida , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/patologia , Próteses Valvulares Cardíacas , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Mitocôndrias Cardíacas/ultraestrutura , Miocárdio/metabolismo
12.
J Surg Res ; 42(3): 247-56, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3821087

RESUMO

The composition of the ideal cardioplegic solution is controversial. Blood cardioplegia is an attractive alternative to standard crystalloid solutions, though its superiority in preserving myocardial metabolism has not been demonstrated. Using a new pH electrode system, this study contrasts the effects of blood and crystalloid solutions upon the generation of myocardial acidosis during global ischemia. Thirty-eight mongrel dogs underwent a 120-min period of aortic cross clamping using systemic hypothermia. To maintain myocardial temperature below 15 degrees C, 19 dogs received multiple doses of a bicarbonate containing crystalloid cardioplegic solution (Group I), while 19 dogs received multiple doses of blood cardioplegia (Group II). Myocardial pH and temperature were continuously monitored in the subendocardial region of the left ventricle. There was no difference in baseline pH between Group I (7.13 +/- 0.05) and Group II (7.17 +/- 0.05, P:NS). With systemic cooling and the initial bolus of cardioplegia, myocardial pH rose to 7.42 +/- 0.04 in Group I and 7.42 +/- 0.06 in Group II (P:NS). After 120 min of global ischemia, myocardial pH decreased to 6.61 +/- 0.05 in Group I and 7.07 +/- 0.05 in Group II (P less than 0.001). Blood cardioplegia was most effective during the first hour of aortic cross clamp when myocardial pH rose by 0.13 +/- 0.04 pH units. In contrast, myocardial pH in Group I during the first hour of global ischemia fell -0.35 +/- 0.08 pH units (P less than 0.001 compared to Group II). During the second hour of cross clamp, myocardial pH declined both in Group I (0.26 +/- 0.03 pH units) and in Group II (0.24 +/- 0.05 pH units, P:NS). However, the accumulation of hydrogen ion during the second hour was significantly greater in Group I (+128.0 +/- 21.4 nm/liter) than in Group II (+36.6 +/- 9.0 nm/liter, P less than 0.001). Thus, myocardial acidosis was reduced during the administration of blood cardioplegia when compared to a bicarbonate-buffered crystalloid solution. The salutary effects of blood cardioplegia on myocardial metabolism stem from blood's significant buffering capacity and its ability to deliver oxygen.


Assuntos
Acidose/prevenção & controle , Sangue , Doença das Coronárias/prevenção & controle , Parada Cardíaca Induzida/métodos , Complicações Intraoperatórias/prevenção & controle , Miocárdio/metabolismo , Acidose/metabolismo , Animais , Doença das Coronárias/metabolismo , Cães , Concentração de Íons de Hidrogênio
14.
Artigo em Inglês | MEDLINE | ID: mdl-3837448

RESUMO

A review of animals receiving a TAH with 4 mechanical valves suggests that the least damage to the blood cell components is associated with the BS valve when compared with the MH valve at similar heart rates. Clinical anemia in varying stages was observed in most animals in this study. However, most calves compensated for the increased rate of hemolysis and none required blood transfusions. The BS valve would appear to combine minimal turbulence and mechanical crushing in a physiological setting.


Assuntos
Próteses Valvulares Cardíacas , Coração Artificial , Animais , Peso Corporal , Bovinos , Frequência Cardíaca , Coração Artificial/efeitos adversos , Hematócrito , Hemólise , Isoenzimas , L-Lactato Desidrogenase/análise , Estudos Retrospectivos , Ovinos
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