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2.  Comparison of in vivo airway responsiveness and in vitro smooth muscle sensitivity to methacholine in man. 
Thorax  1984;39(11):837-843.
Airway responsiveness to methacholine varies between normal people and is increased in patients with asthma. The importance of airway smooth muscle sensitivity in determining in vivo responsiveness is unknown. We have examined this question by comparing in vivo airway responsiveness with in vitro airway smooth muscle sensitivity to methacholine in 10 patients undergoing thoracic surgery. In vivo responsiveness was determined by administration of inhalations of doubling concentrations of methacholine. Results were expressed as the provocation concentration (PC) causing a decrease in forced expiratory volume in one second of 20% (PC20FEV1), specific airway conductance of 35% (PC35SGaw), and maximal expiratory flow at 35% vital capacity, measured for the partial (V35(p)) and complete (V35(c)) flow volume curves, of 35% (PC35V35(p); PC35V35(c)). In vitro airway smooth muscle sensitivity was determined from specimens obtained at thoracotomy. Log dose-response curves to methacholine were constructed and the concentration causing a 50% maximum contraction (EC50) was derived. There were differences between patients for both in vivo airway responsiveness and in vitro smooth muscle sensitivity to methacholine. There were no significant relationships between the in vivo and in vitro measurements. The results suggest that factors other than solely the sensitivity of smooth muscle must determine in vivo airway responsiveness to methacholine.
PMCID: PMC459934  PMID: 6390773
3.  Is there a link between cot death and child abuse? 
Forty five babies delivered in Oxford obstetric units who subsequently died unexpectedly in infancy were compared with 134 controls matched for maternal age, social class, parity, and year of birth to see whether five factors identified in an earlier study as predictive of subsequent child abuse would also predict the sudden infant death syndrome. Epidemiological findings had suggested certain similarities between the two events. In contrast with babies who were abused, four of the five factors did not distinguish between babies who died suddenly and unexpectedly and their controls, but there was a slight increase in the proportion of mothers of babies who died suddenly and unexpectedly for whom nursing staff thought that support and advice on feeding the baby were needed. Factors predictive of child abuse did not predict sudden infant death in this study.
PMCID: PMC1442920  PMID: 6434082
4.  Micro-organisms in gastroenteritis. 
Archives of Disease in Childhood  1984;59(9):848-855.
We present bacteriological and virological findings together with salient clinical features from a prospective study of 447 children aged under 2 years admitted to hospital with infectious gastroenteritis. Putative pathogenic micro-organisms were identified in the stools of 75% of these children. Eight identifiably distinct groups of viruses, found on electron microscopy and tissue culture were present in 67% of patients--rotavirus was detected most frequently. Pathogenic bacteria (salmonellas, shigellas, Escherichia coli, and Campylobacter jejuni--but excluding Clostridium difficile) were found in 16% only. Altogether 4 X 9% of 390 patients had gastroenteritis associated with Cl difficile toxin. The mean duration of diarrhoea was shortest in patients with identifiable virus, with rotavirus having a mean of 5 X 01 days, and was longest in patients with pathogenic bacteria in the stools (11 X 14 days). The finding of more than one type of virus did not seem to be associated with a significantly increased duration of diarrhoea. There are few clinical features which can be associated specifically with any particular micro-organism or groups of these. Multiple organism isolation was common, but the severity of the illness in those patients with at least two types of organism was not greater. Certain viruses, including the norwalk-like virus, known to be associated with outbreaks of gastroenteritis were found as frequently in a group of patients who did not have diarrhoea studied for comparison. Virus was still detectable in the stools of up to 40% of asymptomatic children on the day of discharge.
PMCID: PMC1628695  PMID: 6091568
5.  Food borne infection by a Norwalk like virus (small round structured virus). 
Journal of Clinical Pathology  1984;37(7):817-820.
Two outbreaks of gastrointestinal illness with identical symptoms occurred in parties attending banquets on consecutive evenings at a large hotel. The illness was typical of epidemic winter vomiting disease. Small round structured viruses resembling those seen in the Norwalk Ohio outbreak were identified by electron microscopy in stools of victims from one episode. One food handler was found to be excreting the virus, and there was evidence of a poor standard of hygiene in the kitchen. A food history analysis showed the illness to be significantly associated with eating cold cooked ham.
PMCID: PMC498817  PMID: 6086727
7.  A potential stem-loop structure and the sequence CAAUCAA in the transcript are insufficient to signal rho-dependent transcription termination at lambda tR1. 
Nucleic Acids Research  1984;12(2):1287-1299.
It has been suggested that a sequence in the RNA transcript that can form a stem and loop structure, followed by the sequence CAAUCAA, is the signal for rho-dependent transcription termination. We tested this hypothesis by synthesizing a DNA duplex whose sequence corresponds to a region of the lambda tR1 terminator that contains these structural features. We cloned this synthetic DNA fragment under the control of the lacUV5 promoter, and showed that it does not cause rho-dependent termination in vitro. RNA polymerase pauses during in vitro transcription across the synthetic sequence, although less efficiently than at the corresponding sequence on the lambda template. No rho-mediated termination was detected even under conditions that prolonged transcriptional pausing at the synthetic site, indicating that the synthetic sequence is defective as a transcript release site. We suggest that unlike rho-independent terminators, rho-dependent terminators require sequences in addition to those immediately before the sites of termination.
PMCID: PMC318573  PMID: 6320123

Results 1-7 (7)