[Flow cytometry for the determination of DNA in head and neck carcinomas]

The technique used for DNA determination in tumoral cells from carcinomas of head and neck is described. Results obtained are commented on as is too the future of this technique for the better understanding of the behavior of the tumor and consequently of its treatment.

[Changes in parasitemia evaluated using the modified Strout method in patients with acute Chagas disease under treatment]

Em 18 pacientes com doença de Chagas aguda foi semiquantificada a parasitemia, pelo método de Strout modificado, antes e durante o tratamento. Antes da terapêutica a parasitemia variou entre 1 e 104 tripanossomos, e após o início do tratamento a parasitemia foi lida repetidamente com um intervalo, na maioria dos casos, entre dois e cinco dias, até a negativação. A dose inicial dos medicamentos foi de 10 a 15mg/kg/dia de Nifurtimox para sete pacientes, e 10 a 20mg/kg/dia de Benzonidazol para onze indivíduos. Após início do tratamento com Nifurtimox um paciente ficou o mínimo de cinco e dois o máximo de 23 dias com parasitemia enquanto com o Benzonidazol um paciente permaneceu o máximo de 15 dias.com parasitemia patente. O Benzonidazol baixou a parasitemia mais rapidamente que o Nifurtimox

Genomic DNA sequence polymorphism of Trypanosoma (Schizotrypanum) cruzi isolates with phenotypic variation

1. Single-copy DNA sequences were analyzed by molecular hybridization to determine both the extent of complementarity and time of evolutionary divergence between three isolates obtained from Argentina, Mexico or Venezuela. 2. The Mexico-Venezuela pair appeared much closer than the Mexico-Argentina pair. 3. The tentative values for time of evolutionary divergence were higher than those estimated previously by allozymic variation.

[Supplementation of maternal milk with calcium and phosphorus for the feeding of premature neonates weighing 1500 g or less. How long should it be continued?]

Feeding four preterm infants weighing less than or equal to 1,500 g with human milk supplemented with calcium (160-200 mg/kg/day) and phosphorus (80-200 mg/kg/day) until term postmenstrual age was reached, and suitable levels of plasma calcium, phosphorus and alkaline phosphatase and urinary excretion index of calcium and phosphorus were attained. When such a supplementation was suppressed at 38-40 weeks of postmenstrual age a rapid onset of biochemical disturbances was observed: a rise of plasma calcium (p less than 0.025) and alkaline phosphatase (p less than 0.0025) with a decrease of plasma phosphorus (p less than 0.005) and of urinary phosphate excretion (p less than 0.002). Reincorporation to former supplemented regime results in quick recovery of these parameters. Authors can assert that the necessity of calcium and phosphorus supplementation of human milk for less than or equal to 1.500 g preterm infant feeding exceeds the term postmenstrual age if suitable calcium and phosphorus levels are to be obtained.

[Prevalence of Chagas esophagopathy in the municipality of Mambaí, Goiás-Brazil]

Em Mambaí, área endêmica de doença de Chagas, foram realizadas abreugrafias do esôfago com filme de 70mm, em 1.145 indivíduos do sexo masculino e 1.184 dofeminino, de 4 a 87 anos, dos quais 1.006eram soropositivos. Os pacientes foram posicionados em oblíqua anterior direita e tomadas duas abreugrafias: uma imediatamente à ingestão de 75 ml de suspensão baritada e outra 60 segundos após. Setenta e seis (3,2%) indivíduos apresentaram esofagopatia, sendo que 71(7%) entre os 1.006 soropositivos e, 5(0,37%) entre os 1.323 soronegativos. Dos 76 esofagopatas 47(61,8%) eram do sexo masculino e 29(38,1%) do sexo feminino. Segundo a classificação de Rezende e cols 48(63,1%) pertenciam ao grupo I, 18(23,7%) ao grupo II, 5(6,6%) ao grupo III e 5(6,6%) ao grupo IV. Entre os infectados a esofagopatia aumentou progressivamente com a idade, principalmente a partir dos 30 anos, alcançando a prevalência de 21,5% após os 59 anos.

[Regional organization of a neonatal transportation system]

Organization, operational plans, and initial experience of a Regional Neonatal Transport System is described. The system covers provinces of Bizcaia, and Alava in Northern Spain, with a total of 17,500 annual deliveries. In the first 10 months 31 newborn infants were transported. Their mean birth weight was 2,066 +/- +/- 931 Gm. Ten infants had a birth weight less than 1,500 Gm, and in 22 (71%) of them gestational age was under 37 weeks. Some types of respiratory distress was present in 71% of them, and 25.8% required mechanical ventilation during transport. Hypothermia was present in 36% of the infants at referral center, percentage that decreased to only 9% at their arrival to the NICU. During transport mean body temperature increased from 35.33 +/- 1.07 degrees to 35.84 +/- 0.9 degrees C (p less than 0.01). Infants condition was judged to improve in 13% of them. Overall survival rate was 74.2%, being 80.9% in those weighting from 1,000 to 1,500 Gm. Infants who were hypothermic had a lower survival (45.5%) than those who were not (90%) (p less than 0.05).

Immunoglobulins and other serological parameters in Chagas' disease: evidence for increased IgA levels in the chronic digestive form

Immunoglobulin levels were measured in serum samples from 36 patients with different clinical forms of chronic Chagas' disease. Increased IgA levels were observed in 50% of the patients in the chronic digestive group and there was a significant correlation with the severity of the disease. IgG and IgM levels were within the normal range. Anti-ssDNA antibodies and EVI (endothelium, vessels and interstitium) antibodies were found in some patients with different clinical forms of the disease.

Desialylation of fibrinogen with neuraminidase. Kinetic and clotting studies

The removal, with time, of sialic acid residues from human fibrinogen by neuraminidase, can be explained, as a result of a mathematical analysis, by the summation of two first order reactions with clearly different rate constants. Quantitative studies on the bound sialic acid to isolated fibrinogen chains, after reduction and alkylation of the partially desialylated fibrinogen, show that the fast reaction takes place with the sialic acid bound to the B beta chains. This indicates that the carbohydrate located in the gamma chains is somehow protected or less accessible to the enzyme. Coagulation with thrombin of desialylated fibrinogen shows that the aggregation rate increases linearly as the amount of sialic acid residues decreases, regardless of their location in the fibrinogen molecule.

Genome organization and ploidy number in Trypanosoma cruzi

Trypanosoma cruzi total DNA was analyzed by DNA:DNA reassociation kinetics. The nonlinear least-squares computer solution could reasonably be fitted to three second-order kinetic components. The highly repetitive, middle repetitive, and single copy components comprised 9, 35 and 49% of the genome, respectively. The single copy sequences showed a kinetic complexity of approximately 4 times that of Escherichia coli and of some 11,000 average-sized structural genes. The repetitive sequences (about 6900) presented the long-period pattern of interspersion with a modal length of 7800 bases. The kinetic complexity of total DNA was compatible with a value of at least a diploid genome per cell.

[Early neonatal pneumococcal infections (author's transl)]

Five newborn infants with early pneumococcal infection are presented, two of them died. Until 1978 no cases of this infection were found in our Nursery. In the last three years pneumococcal septicemia has been responsible for nine percent of early neonatal infections. The clinical findings are identical to those seen in type-B beta hemolytic infections. The maternal genital tract colonization maight fetal colonization.

Trypanosoma cruzi ribosomal RNA: internal break in the large-molecular-mass species and number of genes

The large-molecular-mass ribosomal ribonucleic acid from Trypanosoma cruzi probably contains an internal break. The molecule can be obtained in its intact form or in its two fragments depending on the denaturing agents used for its purification and/or display. This break appears to be an in vivo late processing step rather than a random nucleolytic cleavage during in vitro manipulations. Calculations of mass, from gel electrophoretograms, for the large and small main ribosomal ribonucleic acid species and for the two chains derived from the large species gave values of 1.37, 0.84, 0.70 and 0.57 X 10(6) daltons, respectively. Sedimentation velocity measurements in sucrose gradients and in the analytical ultracentrifuge indicated sedimentation coefficients of 24 and 18 S for the large and small main species, respectively. Saturation hybridization curves showed that the nuclear genome, quantified by chemical analysis, contains about 114 ribosomal ribonucleic acid gene copies.

Skin reactions to bug bites as a result of xenodiagnosis

Cutaneous allergic reactions to bites of two bug species Triatoma infestans and Dipetalogaster maxima, were studied in an area where T. infestans is the local domestic vector. While more delayed skin reactions occurred with the indigenous vector, reactions also occurred with D. maxima. Repeated exposure to D. maxima produced more intense immediate skin reactions. First-stage D. maxima bugs produced a lower frequency and intensity of skin reaction. It is concluded that further work on this problem is necessary as it prejudices the use of xenodiagnosis in field surveys.

Jaccoud's arthropathy in patients with chronic rheumatic valvular heart disease

In a prospective study over a period of 3 yr, involving all patients with rheumatic valvular heart disease seen at our hospital, we found the diagnostic signs of Jaccoud's arthropathy in 17 of 400 cases (4.2%). All 17 patients had a past history of acute arthritis involving the joints and showed deformities at the time of diagnosis. The valvular lesions were mitral and aortic in 11 cases, mitral in 5 cases and aortic in 1 case. The most frequent joint deformities were: ulnar deviation at the metacarpo-phalangeal joints (12 cases), lateral deviation at the metatarso-phalangeal joints (12 cases), and hammer toe deformity (6 cases). The deformities were reducible in all of them. None of the patients had pain or signs of acute inflammation and functional capacity was normal. Other causes of joint deformity were ruled out by means of radiographic and serologic studies. Jaccoud's arthropathy is not a rare entity and its recognition is important for a differential diagnosis with chronic arthritis of other etiologies, also associated with valvular heart lesions.

The relationship between overdrive suppression and overdrive excitation in ventricular pacemakers in dogs

We studied the excitatory and inhibitory effects of overdrive on idioventricular pacemakers in anesthetized dogs with recently induced complete atrioventricular block. The following results were obtained: (1) a slow driving rate may induce a temporary rhythm which may be reinstituted with additional stimuli; (2) the induced rhythm may appear as coupled extrasystoles which, on interruption of the drive, are found to be self-sustaining; (3) during continued slow driving, extrasystoles may appear and disappear in a cyclical manner; (4) a short period of fast driving may be followed by a fast new rhythm, the rate and duration of which are a function of the rate and duration of drive; (5) fast driving may induce a new rhythm at a rate below predrive control; (6) after a long period fast driving, only suppression follows; and (7) intermittent periods of fast driving lead to a summation of inhibition with each successive period. These results suggest the following conclusions: (1) under certain conditions, electrical driving instead of inducing suppression may induce a rhythm ("overdrive excitation") at a rate similar to, faster then, or slower ("inhibited excitation") than control; (2) the duration of diastole and the number of driven beats are major factors in the induction of new rhythms; and (3) overdrive excitation is counteracted by overdrive inhibition, with development of the former requiring fewer beats than the latter.