Improved hemodialysis access in children

Vascular access for chronic hemodialysis in children is difficult because of problems that include obtaining vessels of sufficient size, the limited life-span of external shunts, and the multiple painful punctures associated with internal fistulae. Twenty-five expanded polytetraflouroethylene (PTFE) grafts of 6-mm diameter were inserted for dialysis access over a 2-yr period in 23 children. Grafts were placed either in the upper arm or thigh. Each patient was successfully dialyzed from 60 to 370 times. Longterm patency of the PTFE grafts was 88%, with a complication rate of 36%, mostly minor. The same ease of insertion and high flow characteristics were noted in a series of 22 bovine carotid heterograft (BCH) fistulae inserted in the two years immediately preceeding this study. However, the patency rate was only 36% and the complication rate was 69%, mostly major. We consider the PTFE graft fistula to be the preferred method for long-term hemodialysis access in children.

The aphasics' identification of a superordinate's referents with basic object level and subordinate level terms

In a hierarchically-structured semantic field, words at different hierarchical levels exhibit different scopes of reference. The possibility that fluent aphasics could refer more accurately with a subordinate level term than a basic object level term, due to its narrower scope of reference, was investigated in this study. Non-fluent aphasics, fluent aphasics, subjects with insult lateralized to the right hemisphere, and control subjects were asked to name instances of 20 familial superordinates (e.g., vegetables). Responses which were basic object level names (e.g., squash) and those which were subordinate level names (e.g., acorn squash) were analyzed separately. Aphasics produced fewer responses overall than non-aphasic subjects, although they produced larger proportions of subordinate level responses than non-aphasics. An analysis of the basic object level names revealed that the non-fluent aphasics produced the most highly representative instances of a superordinate, while the fluent aphasics provided the least representative instances, often naming out-of-set referents. In marked contrast, an examination of the subordinate level responses revealed that the fluent aphasics were as accurate as any other subjects in naming out-of-set referents. In marked contrast, an examination of the subordinate level responses revealed that the fluent aphasics were as accurate as any other subjects in naming instances of a superordinate. These data, in conjunction with the findings of other recent studies, suggest some to the skills which the fluent aphasics may successfully bring to bear in their attempts to refer with a word.

Cytomegaloviruria in older infants in intensive care nurseries

Over a four-month period, urine specimens for viral isolation were obtained weekly from all infants older than three weeks in two intensive care nurseries. These babies comprised 43% of the patients in the nurseries surveyed. Cytomegalovirus was cultured from 13 of 93 (14%) of these infants. Eleven of 13 infants who developed cytomegaloviruria were born prematurely, and nine of these 11 were found to be excreting CMV before they reached 40 weeks postconception. Infants excreting CMV received blood transfusions from a mean of 10.45 (+/- 1.80 SE) different donors versus 5.10 (+/- 0.55 SE) for infants without viruria (P less than 0.002) and five of 14 infants undergoing one or more exchange transfusions developed cytomegaloviruria (P less than 0.05). The possible role of other CMV reservoirs and the importance of these findings are discussed.

Prospective study of chlamydial infection in neonates

Chlamydia trachomatis was recovered from the cervices of 4% (36/900) of pregnant women tested. 20 infants born through chlamydia-infected cervices were followed up for a year, as were 18 infants born to chlamydia-negative mothers. A statistically significant excess of conjunctivitis and pneumonia was found in infants exposed to chlamydia. The attack-rate for inclusion conjunctivitis was 35% (7/20) and for chlamydial pneumonia it was 20% (4/20). Chlamydiae were recovered from 10 of the 20 (50%) exposed infants, and seroconversion was demonstrated in 14 (70%). None of the 18 unexposed infants showed evidence of chlamydial infection. Thus in our clinic 2.8% of all newborns acquired chlamydial infection, with incidence-rates of 14 cases of conjunctivitis and 8 cases of pneumonia per 1000 live births. Neonatal chlamydial infection is thus a major public-health problem warranting a preventive programme based on the fuller provision of diagnostic services and the treatment of infected pregnant women.

Antithymocyte globulin in the management of cutaneous T cell lymphoma

Four patients with cutaneous T cell lymphoma were treated with iv administered horse antithymocyte globulin. Evidence of a beneficial response was obtained in three of the four patients. Limited sensitivity of neoplastic T cells to complement-mediated lysis in the presence of the antithymocyte globulin was identified, suggesting that other mechanisms may be responsible for the observed clinical responses.

Infection with Chlamydia trachomatis: involvement of multiple anatomic sites in neonates

In a study of infection due to Chlamydia trachomatis in infants, chlamydiae were recovered not only from the conjunctiva and respiratory tract but also from the vagina and rectum. The timing of recovery suggested that the vagina and conjunctivae are exposed to chlamydiae at birth and that pneumonia and gastrointestinal infection occur later. Sampling of the rectum may be a useful procedure for the diagnosis of chlamydial disease in infants.

The effect of feeding on the cerebral neurosecretory system of the adult male tsetse, Glossina austeni Newst

An analysis of the intensity of staining of the corpus cardiacum and of the neurosecretorty cells of the pars intercerebralis in 3-day-old fed or fasting adult male tsetse has revealed two periods of apparent release of neurosecretion. In fed males, stainable neurosecretion disappears from 14 of the 20 recognizable neurosecretory cells within 10 min of the termination of feeding. There is always less neurosecretory material in the corpora cardiaca of fed males. Secondly, there is an indication of a depletion of material from the cardiaca of both fed and fasted males at about 1700 hours EST.

Heating of metallic intrauterine contraceptive devices during ultrasound examination

Heating of metallic IUDs during ultrasound examination has been suggested as a possible hazard to surrounding tissues. Serial temperature measurements of such devices during insonation with commercially available ultrasound equipment show no temperature changes during prolonged exposure. The results indicate that the possibility of significant heating of metallic objects within the body may be disregarded in clinical practice.

Antepartum ultrasonic diagnosis of congenital hydrocele

Ultrasound scans are presented in 2 cases of bilateral congenital hydroceles. In both cases, large scrotal sacs were identified and seen to contain prominent fluid collections. In one case, the testes were identified within the fluid. No testes were seen in the other patient, who subsequently proved to have bilateral undescended testicles.

Gastroesophageal reflux: a potential source of confusion in technetium thyroid scanning:case report

Technetium-99m as pertechnetate, excreted into the stomach after intravenous injection and refluxed as high as the cervical esophagus can present a confusing picture during thyroid scintigraphy if one is not aware of this possibility. The typical appearance of refluxed tracer is presented, and a simple method for eliminating the confusion is suggested.

Metastases to the esophagus causing gastrointestinal bleeding

A case of hypernephroma metastatic to the esophagus and presenting with massive upper gastrointestinal hemorrhage is described. The literature on metastatic esophageal neoplasm is reviewed and the methods of spread and prognosis summarized.

Theoretical modifications of reciprocal recurrent selection

Reciprocal recurrent selection (RRS), which assumes overdominant loci to be important, alters two genetically different populations to improve their crossbred mean. Individual plants from two populations (A and B) are selfed and also crossed with plants from the reciprocal female tester population (B and A, respectively). Selection is based on the mean of crossbred families, and the selected individuals are randomly mated within A and B to form new populations.--We propose two alternatives to RRS. The first (RRS-I) uses, as the tester of population A, a population (LB) that is derived from population B by family selection for low yield. The second (RRS-II) is similar to RRS-I, but also uses, as the tester of B, a population (LA) that is derived from population A by family selection for low yield.--The expected crossbred means of RRS, RRS-I, and RRS-II were compared, assuming equal sigmaP, at several cycles of selection for incomplete and complete dominance, and for several cases of overdominance (depending on the gene frequencies in A and B, and on the equilibrium gene frequency).--The choice of selection method depends on the importance of the effects of overdominant loci compared to loci exhibiting incomplete or complete dominance. If overdominance is unimportant, RRS-II is the best selection method, followed by RRS-I and RRS. If overdominance is important, both RRS and RRS-I are superior to RRS-II; RRS is preferred to RRS-I if the effects of overdominant loci are sufficiently important. If the genetic model is a mixture of levels of dominance at different loci, a combination of selection systems is suggested.

Recurrence of group B streptococcal infection

It is clear that the group B streptococcus has become a major pathogen of young infants within the comparatively recent past. Further it is clear that, as with other endemic and epidemic pathogens, increasing clinical and laboratory experience brings to light variations not initially evident. In addition, therapy presumably effective in initial cases may not continue to be so. The following papers by coincidence were received over a relatively brief period of time. Hence, for emphasis of some of the problems related to this organism, they are presented as a group.

Spectrofluorometric Studies. XI. Some Aspects of the Photochemistry of Ortho-fused Benzocycloalkenes

Fluorescent yields of[Formula: see text]excited in the 2500 Å region in cyclohexane solution have been examined. There is a general trend of fluorescent yields decreasing with increasing alkene ring size. The sum of the fluorescent and triplet yields decreases with increasing ring size. Triplet energies, obtained by Evans' method and roughly confirmed by phosphorescent emission spectra at 77 °K, do not vary greatly.

Sampling variance of the correlation coefficients estimated from analyses of variance and covariance

A generalized sampling variance of correlation coefficients is derived for phenotypic, genetic and en vironmental correlations estimated from nested analyses of variance and covarianee for the equal number case. A numerical example is presented to estimate the sampling variance for the genetic correlation coefficient based on the relationship among full sibs using unequal subclass numbers.

On the absence of triplet ketene in ketene excited in the region 2800–3660 Å

The sensitized biacetyl emission technique was used in an attempt to detect triplet ketene molecules, which might be formed when ketene is excited by light ranging in wavelength from 2800 to 3600 Å. No sensitized emission was observed in this exciting wavelength region thus confirming the recent results of Voisey (1) which also show that triplet ketene is not produced when ketene is excited by light between 2800 and 3200 Å, and that the triplet CH2 found in such systems must arise from some source other than triplet ketene.