[Streptokinase in severe pulmonary thromboembolism]

Severe pulmonary embolism (PE) was treated with streptokinase in four patients, three men and one woman, age 38 to 72 (mean = 53 +/- 14) years. Before the thrombolytic therapy, all patients had pulmonary angiogram and hemodynamic parameters analyzed. The drug was infused through the distal lumen of the Swan-Ganz catheter at the pulmonary artery trunk. The initial dosage was 250,000 units "in bolus" and 100,000 units in 24 to 72 hours. The time interval between the symptoms and treatment had ranged from 2 hours to 5 days. The results are analyzed as follow: reduction on right atrial pressure, mean pulmonary pressure, pulmonary vascular resistance, an increase in the stroke volume and cardiac output. In two cases we observed total lysis, in one partial lysis and one patient died from severe form of PE and late infusion of SK. Reinfusion of the drug was necessary in one patient that had PE recurrence with reliable final result. Finally, no one had severe bleeding despite the use of the intrapulmonary catheter.

Determinantes do processo de infestação domiciliar por Panstrongylus megistus: o papel da habitação e do desmatamento

A qualidade das habitações e o desmatamento foram estudados em Caconde e São José do Rio Pardo, municípios paulistas com taxas diferenciadas de infestação domiciliar por Panstrongylus megistus, e com desenvolvimento sócio-econômico dessemelhante. Para o conhecimento da qualidade das habitações recorreu-se a dados registrados na Superintendência de Controle de Endemias (SUCEN) durante a década de 70; o estudo do desmatamento foi realizado em mapas, construídos por nós a partir de fotografias aéreas, obtidas em vôos realizados pela Secretaria de Agricultura em 1972 e 1983. A análise sócio-econômica baseou-se nas informações do Censo Agro-pecuário e em entrevistas com agrônomos dos municípios. O estudo mostrou uma situação de maior precariedade das casas em Caconde. Essa situação decorre do menor desenvolvimento sócio-econômico deste município, confirmando assim uma tendência já demonstrada em pesquisas anteriores. O desmatamento foi mais intenso em São José, onde o desenvolvimento social é maior e no qual à taxa de infestação é menor, fato que mostra um comportamento oposto entre os dois determinantes nestes municípios. Os vínculos entre o desmatamento e o maior desenvolvimento sócio-econômico pode também ser demonstrado na medida em que se pode relacionar a atividade produtiva com a destruição da cobertura vegetal natural. Cabe sublinhar que esta tendência de efeito oposto do desmatamento não inverteu o resultado final, ou seja, que o confronto dessas forças determinantes resultou ainda numa taxa de infestação superior em Caconde, área de menor desenvolvimento social. A existência dessas tendências opostas entre os determinantes revela, desse modo, uma maior complexidade no processo de infestação por P. megistus, sem produzir, no entanto, reversão do resultado final.

[Determinants of the process of domiciliary infestation by Panstrongylus megistus: the role of housing and deforesting]

This study investigates the housing conditions and deforesting in Caconde and São José do Rio Pardo, neighbouring towns located in the northeastern region of the State of São Paulo, Brazil. These localities have had different dwelling infestation rates by Panstrongylus megistus and they also show distinct socioeconomic development. The housing conditions were studied by the analysis of data collected during the 1970's by the Superintendência de Controle de Endemias (SUCEN), a government agency. Aerial photographs taken during flights performed by the Agricultural Department of the State were used to analyse the deforesting. The socioeconomic analysis was based on Agricultural Census and interview with agronomic officials. The study showed more precarious housing conditions in Caconde than in São José do Rio Pardo. It was related to lower socioeconomic development in Caconde, confirming a trend showed by previous studies. The deforesting was more intense in São José, where socioeconomic development has been higher and the infestation rates were lower, what demonstrates opposite behaviour between the two determinants in these towns. The links between deforesting and higher socioeconomic development can also be showed by the relation between productive activity and destruction of the natural agricultural covering. It is emphasized that the tendency of opposite effect of the deforesting did not change the final result, that is, the confrontation of these determinant forces resulted in higher infestation rates in Caconde than in São José do Rio Pardo. The existence of these opposite trends between the determinants disclosed therefore more complexity in the infestation process of P. megistus, although the final result was not reverted changed.

Detection of blood vessels in retinal images using two-dimensional matched filters

Blood vessels usually have poor local contrast, and the application of existing edge detection algorithms yield results which are not satisfactory. An operator for feature extraction based on the optical and spatial properties of objects to be recognized is introduced. The gray-level profile of the cross section of a blood vessel is approximated by a Gaussian-shaped curve. The concept of matched filter detection of signals is used to detect piecewise linear segments of blood vessels in these images. Twelve different templates that are used to search for vessel segments along all possible directions are constructed. Various issues related to the implementation of these matched filters are discussed. The results are compared to those obtained with other methods.

[Therapeutic evaluation of praziquantel (Embay 8440) in human infection due to S. mansoni]

Foram tratados com praziquantel, dose oral única de 40 ou 50 mg/kg, 200 indivíduos portadores de esquistossomose mansoni, matriculados na Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. As idades dos pacientes variavam de seis a 63 anos, sendo que 33 (16,5%) eram menores de 15 anos. Os principais efeitos colaterais consistiram em tontura 27,5%; sonolência 21,0%; eólica 17,5%; náusea 16,0%; diarréia 9,0%; cefaléia 7,5%; vômito 4,0%; febre 2,0%; disenteria 1,0%; tremor 1,0%; exantema 1,0% e urticaria 0,5%. A toxicidade do medicamento foi investigada mediante a realização, pré e pós-tratamento, de exames hematimétricos, bem como de função renal (uréia e creatinina), hepática (enzimas de liberação hépato-canalicular e bilirrubinas), cardíaca (ECG) e neuropsiquiátrica (EEG). Não foram encontradas nesses controles alterações relevantes que repercutissem clinicamente. O controle de cura verificou-se em 115 indivíduos, através de oito coproscopias, no período de seis meses, subseqüente ao tratamento, utilizando-se duas técnicas (HOFFMAN e KATO/KATZ) para cada amostra de fezes. Dos 82 indivíduos que tiveram as oito coproscopias negativadas, 62 realizaram biópsia retal. Essa mostrou-se positiva em duas oportunidades, indicando um percentual de 3,2% de achados falsos negativos com relação às coproscopias. Os índices de cura variaram de 65,2%, nos pacientes menores de 15 anos, a 75% nos acima dessa idade. Para todas as faixas etárias a eficácia foi de 71,3%. Os resultados obtidos demonstram ter o praziquantel, nas doses empregadas, relativa eficácia no tratamento da esquistossomose mansoni, bem como ser determinante de baixos efeitos tóxico-colaterais.

The immune response to homologous lens crystallin. I. Antibody production after lens injury

Using a sensitive radioimmunoassay to homologous mouse alpha-crystallin, it was established that autoantibodies are produced to this self constituent in mice after rupture of the lens capsule by needling. Antibody to lens crystallin was detected within 4 days of lens rupture and persisted for 24 days, suggesting that these mice are not tolerant to alpha-crystallin at the B cell level. However, T cells from mice immunized with homologous crystallin cannot be stimulated to proliferate by either homologous or heterologous crystallin. On the other hand, lymphocytes from mice immunized with bovine alpha-crystallin can be stimulated to proliferate to bovine crystallin, but not to either unfractionated mouse crystallin (MC) or purified mouse alpha-crystallin. At the level of detection, therefore, T cells appear to be tolerant to homologous alpha-crystallin, but not to heterologous alpha-crystallin. LPS resulting from bacterial contamination after needling was ruled out as a necessity for antibody production because antibody to mouse alpha-crystallin was produced after sterile lens rupture with a laser. However, LPS and poly A:U did enhance the antibody response to alpha-crystallin. These data suggest that T cells, but not B cells, are tolerant to homologous crystallin and that antibody results from circumvention of specific helper T cell requirements for antibody synthesis. The implications of these findings for tolerance and autoimmune uveitis are discussed.

The immune response to homologous lens crystallin. I. Antibody production after lens injury

Using a sensitive radioimmunoassay to homologous mouse alpha-crystallin, it was established that autoantibodies are produced to this self constituent in mice after rupture of the lens capsule by needling. Antibody to lens crystallin was detected within 4 days of lens rupture and persisted for 24 days, suggesting that these mice are not tolerant to alpha-crystallin at the B cell level. However, T cells from mice immunized with homologous crystallin cannot be stimulated to proliferate by either homologous or heterologous crystallin. On the other hand, lymphocytes from mice immunized with bovine alpha-crystallin can be stimulated to proliferate to bovine crystallin, but not to either unfractionated mouse crystallin (MC) or purified mouse alpha-crystallin. At the level of detection, therefore, T cells appear to be tolerant to homologous alpha-crystallin, but not to heterologous alpha-crystallin. LPS resulting from bacterial contamination after needling was ruled out as a necessity for antibody production because antibody to mouse alpha-crystallin was produced after sterile lens rupture with a laser. However, LPS and poly A:U did enhance the antibody response to alpha-crystallin. These data suggest that T cells, but not B cells, are tolerant to homologous crystallin and that antibody results from circumvention of specific helper T cell requirements for antibody synthesis. The implications of these findings for tolerance and autoimmune uveitis are discussed.

Sickled erythrocytes, hyphema, and secondary glaucoma: III. Effects of sicle cell and normal human blood samples in rabbit anterior chambers

When injected into rabbit anterior chambers, human sickle cell erythrocytes cause more intense and prolonged effects than do nonsickling erythrocytes. The consequences of injected sickle cell trait erythrocytes are not less severe than those of injected SC, SS, and Sthal erythrocytes. Regardless of hemoglobin composition, blood with a higher hematocrit value causes more severe complications than blood with a lower hematocrit value.

Calibration error in dark adaptometer

We noted that the adjustable fixation device present on some models of the Goldmann-Weekers dark adaptometer has a calibration error that results in a consistent and predictable overestimation of retinal eccentricity. The error occurs because the eye being tested is not in the geometric center of the projection sphere. The true retinal locus may be computed by trigonometric analysis. A conversion table is available for reference.

Proliferative retinopathy in sickle cell trait. Report of seven cases

Seven patients had sickle cell trait (hemoglobin AS) and vasoproliferative retinopathy. The retinal abnormalities in these seven patients were indistinguishable from those seen in patients with clinically significant sickling hemoglobinopathies (sickle cell-hemoglobin C disease, hemoglobin S-thalassemia disease, and sickle cell anemia). All seven patients also had some evidence of associated systemic disease such as diabetes, syphilis, tuberculosis, or sarcoidosis. In the presence of an associated systemic disease, marked retinopathy can occur in the ordinarily benign condition of sickle cell trait.

Macular and perimacular vascular remodelling sickling haemoglobinopathies

The posterior pole vasculature of 100 patients with different sickling haemoglobinopathies was studied prospectively over a period of three years. Various abnormalities of the posterior pole vasculature were seen in 29 per cent of the patients. Continuous remodelling of the macular and perimacular vasculature occurred. Visual acuity was variably affected and sometimes remained intact.

Angioid streaks and sickle haemoglobinopathies

Five patients had angioid streaks associated with sickle cell haemoglobinopathy. Other diseases associated with angioid streaks were ruled out, as was elastic tissue degenegation in sickle cell patients. After studying over 350 patients, we believe the incidence of angioid streaks in sickle cell disease to be between 1 and 2 per cent.

Evolution of the retinal black sunburst in sickling haemoglobinopathies

In a prospective study of 38 patients, who were initially selected as being at an early stage of sickling retinopathy, three developed circular black chorio-retinal scars (black sunbursts) during a period of 6 to 24 months. These lesions appear to be the sequelae of intraretinal and subretinal haemorrhage. They occur in the fundus periphery and do not interfere with vision.

Ischemia of ciliary arterial circulation from ocular compression

Two patients developed unilateral central retinal artery and posterior ciliary artery occlusions related to ocular compression during general anesthesia. One patient had evidence of extensive choroidal ischemia with diffuse hypopigmentation, pigmentary mottling of the posterior pole, and disc edema. Electroretinography showed diminution of the A and B waves. The other patient showed patchy choroidal ischemia with subsequent development of wedge-shaped areas of pigmentary atrophy and mottling in the midperiphery. Iridocyclitis and prolonged hypotony were also present. Retinal and posterior ciliary artery occlusion (perhaps at the level of the ophthalmic artery) can occur as a result of ocular compression by a face mask or an improperly positioned headrest. Systemic hypotension is a factor in many cases. Proper positioning of the head on an adequate headrest and avoidance of ocular compression will prevent the occurrence of retinal and choroidal occlusion during general anesthesia.

Dark-without-pressure fundus lesions

Seven black patients had dark brown homogeneous geographical areas of the fundus. Six cases were associated with sickle cell haemoglobinopathies and one was associated with systemic hypertension. These flat lesions were uniform in colour and occurred in the posterior pole or in the midperiphery. They appeared to be transient and often disappeared leaving no residue. The cause is unknown. By analogy with white-without-pressure fundus lesions, we have called these areas dark-without-pressure.