Flow cytometric enumeration of absolute lymphocyte number in peripheral blood using two parameters of light scatter

A method was developed to measure the absolute lymphocyte count (ALC) of whole blood using the Spectrum III automated flow cytometer. Ninety-nine samples of human peripheral blood were analysed on the Spectrum and the Coulter Counter S Plus II, to allow for comparison of the two machines. Regression analysis was used to test the extent of agreement between the sets of measurements on the two machines. The results demonstrated that the slope of the regression line was not significantly different from one, indicating a high level of correlation between Spectrum and Coulter ALC's. However, the mean difference between Coulter and Spectrum ALC's was not equal to zero, with the Spectrum giving counts approximately 10% lower than those of the Coulter machine. This is attributed to the different ways by which the two machines define a lymphocyte, the Spectrum III by two parameters of light scatter and the Coulter S Plus II by the single parameter of cell volume.

'Pitted' erythrocytes: impaired formation in splenectomized subjects with congenital spherocytosis

'Pitted' erythrocyte counts are widely used in the quantitative assessment of functional hyposplenism and in the prediction of recurrence of splenic function in splenectomized subjects. Both of these functions require counts from electively splenectomized controls for comparison. The 'pitted' erythrocyte counts in patients splenectomized for congenital spherocytosis are lower than those found in subjects whose spleens were removed electively for other reasons. This appears to be due to the specific membrane defect which impairs the formation of the vacuoles which are responsible for the appearance of 'pitted' erythrocytes under the interference-phase microscope.

Choledochal cysts--report of three cases and review

Three cases of choledochal cyst are presented, with a review of previous publications. We re-emphasize the diagnostic dilemma involved and discuss current surgical management. A new complication is illustrated and an association with polycystic kidneys is reported. Choledochal cysts are uncommon, but correct management ensures a symptom-free future for the patient. Recent reports support cyst excision if technically feasible.

Semiautomated determination of minimum bactericidal concentrations of antibiotics

Using a newly devised 50-channel photometer which records the opacity of growing bacterial cultures, it was shown that the time taken by cultures diluted 1/1000 in fresh broth to reach 50% of the opacity of a fully grown culture was inversely related to the concentration of organisms in the original culture. This relation was used to determine the numbers of survivors after exposure to benzylpenicillin and gentamicin alone and in combination. The procedure is commended as a labour-saving and potentially rapid method of obtaining comprehensive information on the bactericidal action and interaction of antibiotics.

Intraregional basis for sequential filling and emptying of the lung

We studied the sequential pattern of lung filing by measuring the slope of the alveolar plateau in single breath helium washouts after inhaling a bolus at a lung volume (VI) equivalent to 20. 40, 60 and 80% of vital capacity (VC). In seated subjects, prone dogs, both with the chest intact and wide open, and individual canine lobes, slopes at VI = 20% VC were more positive than those at VI = 80% VC, indicating a "first in - last out' pattern. Furthermore the range of slopes, which reflects the magnitude of sequencing, was comparable in the four situations. We conclude that sequential filing and emptying of the lung has predominantly an intraregional basis. A two compartment optimization analysis using single exponential pressure-volume curves suggests that only a small proportion of the lung needs to behave differently to produce the sequencing observed in individual lobes.

Seasonal pattern in childhood viral lower respiratory tract infections in Melbourne

Respiratory syncytial virus and parainfluenza viruses are the major pathogens in acute lower respiratory infection in infants and younger children. They show distinct seasonal patterns. An annual epidemic of respiratory syncytial virus infection is seen in Melbourne and this coincides with the coldest months of the year. Parainfluenza virus Type 1, the most frequent cause of laryngotracheobronchitis, occurs as an autumn epidemic every second year. Parainfluenza virus Types 2 and 3 are present most years and do not show a clear seasonal pattern.

Metabolic Sources of Heat and Power in Tuna Muscles: I. Muscle Fine Structure

As part of an investigation into the generation of muscle heat in the tuna, the histochemistry and ultrastructure of the myotomal muscles were studied. Both red and white fibres are differentiated into two forms. The two forms of red muscle are very similar except for differential electron absorbance and different kinds of glycogen granules stored. In both forms, capillarity, mitochondrial numbers, and intracellular lipid droplets are abundant, implying the potential for a vigorous aerobic metabolism. During bursts of swimming, glycogen granules and intracellular lipid droplets are both largely depleted. The two types of white fibre differ in electron absorbance, pinocyotic activity, glycogen abundance, and insertion pattern, all of which are more pronounced in the ‘dense’ fibre form. Several features of tuna white muscle are unique or unusually developed. Thus, tuna muscle contains more glycogen than does red muscle. Glycogen granules may be randomly dispersed in myofibrillar or peripheral regions or may be sequestered in membrane-bound structures termed glycogen bodies. During short bursts of swimming, glycogen granules from all storage sites are mobilized. The white muscle has an ample capillary supply, small, but significant, amounts of intracellular lipid, and unusual numbers of mitochondria.

Influenza A and B virus infection in infants and young children during the years 1957-1976

Influenza A virus activity was demonstrated in infants and young children from metropolitan Washington, DC during each of 19 successive August-July respiratory disease years, and during 17 of these years at least 2% of hospitalized respiratory disease patients yielded an influenza A or B virus and/or showed an influenza A or B serum complement-fixing (CF) antibody response. Between October 1957 and July 1976, 14.3% of 860 croup patients and 5.3% of a total of 5655 hospitalized respiratory patients, including croup patients, showed evidence of influenza A or B infection. The mean period of hospitalization with either virus was about 8 days, though serious infection with influenza A virus was 4.5 times more common than with influenza B virus. Both influenza viruses were detected more frequently in respiratory disease outpatients than in respiratory disease inpatients. Patients with serious influenza A virus infections were especially likely to have croup (particularly during the H3N2 era), to be seen during December through February, and to be black male infants. During the peak month of a composite of 13 consecutive influenza A virus outbreaks, influenza A virus infection was demonstrated in 67.6% of croup patients and in 35.6% of all hospitalized respiratory patients including croup patients. During the peak month of a composite of 6 consecutive influenza B virus outbreaks, influenza B virus infection was demonstrated in 36.0% of croup patients and in 10.8% of all hospitalized respiratory disease patients including croup patients.

Flow dependence of gas distribution and the pattern of inspiratory muscle contraction

We measured regional distribution of xenon-133 boli at 0.25, 0.75, and 1.5 l/s in four normal seated subjects during inspirations performed predominantly with intercostal and accessory muscles (IC) or with the diaphragm, accompanied by outward abdominal motion (Ab). In six additional subjects we inferred the topographical distribution of helium boli during similar breaths and flow rates from the slope of the alveolar plateau recorded during a slow expiration (less than 0.5 l/s). Distribution of the helium boli was studied during natural as well as IC and Ab inspirations. At each of the flow rates IC breaths distributed relatively more of the inspired bolus to upper lung regions than did Ab inspirations. Natural breaths at 0.25 l/s resulted in distributions similar to those of Ab inspirations, whereas at 1.5 l/s the distribution approached that of IC inspirations. A three-compartment model, representing upper, middle, and lower lung regions, was used to simulate bolus distribution. The experimental data showed substantial departure from predictions based on regional time constants alone. However, additional small differences in applied pressure (less than 0.50 cmH2O) between the regions satisfactorily accounted for the gas distribution.

Third component, HBeAg/3, of hepatitis B e antigen system, identified by three different double-diffusion techniques

A third component, HB(e)AG/3, of the hepatitis B e antigen system has been detected, and it was consistently detected in three variations of the double-diffusion technique.