The clinical significance of Haemophilus influenzae and H. parainfluenzae isolated from the sputum of adult patients at an urban general hospital

Fifty-seven patients, from whose sputum Haemophilus influenzae (49 cases) or Haemophilus parainfluenzae (8 cases) was isolated during a 7-month period, were studied. In the majority of cases there were well-defined predisposing factors to respiratory tract colonisation or infection with the isolates, in particular bronchiectasis and chronic obstructive airways disease. Colonisation of the airways, bronchopneumonia in patients with underlying lung disease, acute lobar pneumonia, and postoperative chest infections were the commonest clinical diagnoses. Primary acute lobar pneumonia with these organisms alone was uncommon. All of the H. influenzae isolates were nontypeable, and there was a wide range of biotypes of both organisms. Three H. influenzae isolates produced beta-lactamase, and there was, in general, a low incidence of resistance to a wide range of antimicrobial agents on disc susceptibility testing.

Hemisphere preference, phobia, and depression

The present study was undertaken in order to examine whether depression and anxiety are related to preference for a right hemisphere mode of thinking. On the basis of a paper-and-pencil test presumably measuring hemisphere preference (Preference Test; Zenhausern, 1978), normal subjects (N = 75) were assigned to a group characterized by a left hemisphere thinking style, a group characterized by a right hemisphere thinking style and a group with mixed tendencies (left and right hemisphere tendencies). Additionally, subjects completed the Fear Questionnaire and the Depression Symptom Inventory. It was found that subjects with a right hemisphere thinking style reported more depressive and fear symptoms than subjects with a left hemisphere thinking style. This finding is in line with theories which assume that the right hemisphere is characterized by a negative, dysphoric emotional tendency.

Waning of panic sensations during prolonged hyperventilation

Recent theories about panic emphasize that a hyperventilatory positive feedback loop is involved in panic: catastrophic misinterpretation of bodily sensations may trigger anxiety, anxiety may stimulate hyperventilation, hyperventilation may promote the salience of feared sensations etc. Such models leave unexplained how and when panics come to an end. It was hypothesised that panic with hyperventilation may end because pronounced hyperventilation becomes, in the course of time, less powerful in generating perceivable bodily sensations. Twenty healthy subjects hyperventilated forcefully and experienced clear panic symptoms as defined by DSM IIIR. When pCO2 was kept 55% below base line for 90 min, panic symptoms waned. The mean intensity of the symptoms declined as did the number of symptoms occurring. No panic symptoms were observed in the control group (n = 20) who ventilated normally. In so far as hyperventilation is involved in the positive feedback loops that characterize panic, panic attacks may be time-limited because sensations induced by hyperventilation become less salient even if massive hyperventilation continues. As to the explanation of the reported phenomenon, it is suggested that, apart from habituation, local physiological changes due to prolonged hyperventilation may produce a decrease in interoceptive input.

The different intracellular action potentials of fast and slow muscle fibres

The time course of the intracellular action potential was studied quantitatively, because it is an important factor in the generation of electromyographic signals. In in vivo preparations of the m. EDL and m. soleus of the rat single motor units were stimulated and intracellular action potentials were recorded in muscle fibres belonging to those motor units. In this arrangement it was possible to relate the intracellular action potential to the fibre type. The intracellular action potentials of fast twitch glycolytic (FTG) EDL and of slow soleus fibres were described, using 8 characteristics. All characteristics but one differed significantly between the two fibre populations. Comparing characteristics of intracellular action potentials of FTG fibres with slow fibres, it is concluded that: the resting membrane potential is more negative; the amplitude of the action potential is larger; the maximum rates of depolarization and repolarization are higher; and the shape of the repolarization phase is more variable.

Hepatitis B vaccination in Down's syndrome and other mentally retarded patients

The immune response after vaccination with H-B-VAX (20 micrograms, Months 0, 1 and 6) was investigated in 23 Down's syndrome patients and compared to that in 30 other mentally retarded patients and 32 staff members. About 90% of Down's syndrome and other mentally retarded patients and 100% of staff members had anti-HBs at Month 9, but anti-HBs less than 10 IU per liter were found in 6/23 (26.1%) of Down's syndrome, 7/30 (23.3%) of other mentally retarded patients, in contrast to 2/32 (6.2%) of staff members. No differences in anti-HBs response with regard to sex and age were observed in staff members, but geometric mean titers of anti-HBs were lower in older Down's syndrome and other mentally retarded patients, and in male Down's syndrome patients. Supplementary vaccination is necessary in these individuals to obtain "protective levels" of anti-HBs.