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Notes: The Grassberger–Procaccia dimension is determined from pressure and temperature measurements in a pool of water agitated by steam injection. For this complex flow system, three distinct values of dimension ranging from ∼4.2 to ∼8.0 (corresponding to three different measurement locations) are obtained.

Notes: Laryngospasm occurring after tracheal extubation in children is potentially dangerous. This study uses acupuncture with bloodletting at the Shao Shang (L 11) or Shang Yang (Li 1) acupoints to investigate whether this technique can prevent or treat laryngospasm. Seventy-six patients were randomly divided into two groups. Patients in the acupuncture group (n = 38) were treated with bilateral Shao Shang acupunctures at the end of the operation. Patients in the control group (n = 38) were not. The incidence of laryngospasm in the acupuncture group (5.3%) was less than that in the control group (23.7%) (p 〈 0.05). If laryngospasm developed, patients were immediately treated with acupuncture at either the Shao Shang or Shang Yang acupoints. As judged by an increase in peripheral oxygen saturation, the laryngospasm was relieved within 1 min of acupuncture in all patients. It is concluded that acupuncture with bloodletting at the Shao Shang acupoint may prevent and treat laryngospasm occurring after tracheal extubation in children.

Notes: Several vaccination studies have been performed in monkeys and humans testing the feasibility of prophylactic and therapeutic immunizations against Helicobacter pylori. The monkey studies showed that immune responses were induced by oral vaccination with the mucosal adjuvant LT (Escherichia coli heat-labile enterotoxin), parenteral administration with a cationic lipid adjuvant, and by mucosal priming followed by parenteral boosts. Both prophylactic and therapeutic activities were demonstrated in monkeys, providing a strong impetus for human vaccine trials. Preliminary studies in humans were undertaken in order to identify a tolerable dose of LT adjuvant or to test the effectiveness of mutant atoxic LT adjuvants. The results from these preliminary studies suggest that native LT causes diarrhoea at doses required for adjuvanticity while a mutant LT does not. In one study in which infected human subjects were vaccinated with orally administered urease antigen with native LT, there was a modest reduction in the level of H. pylori gastric colonization. A second clinical study employing H. pylori whole cell antigen and a mutant LT in infected subjects showed immune responses and although the subjects remained infected, the study was not designed to measure reduction in H. pylori colonization. Recombinant Salmonella expressing urease and other H. pylori antigens have been effective in mice (see accompanying Frontlines Topic Review by John O. Nedrud [1]), but monkey studies are not possible because of host range restriction. Human trials of parenteral immunization, mucosal immunization with mutant LT and live Salmonella vectors are needed to fully assess the ability of vaccines to prevent or treat H. pylori infections.

Notes: Summary. About half of the haemophiliacs in Hong Kong have been infected by human immunodeficiency virus (HIV). This study aimed to determine their clinical course of progression. Forty-seven adult patients with congenital coagulation factor deficiency being followed up regularly from January 1992 onward in the Department of Medicine of Queen Mary Hospital, Hong Kong, were included in this study. Twenty were positive for HIV antibody and the remaining 27 were negative. Three other HIV-positive patients who died before 1992 were excluded. From January 1992 to June 1996, the 47 patients included in the study were followed up in the clinic every 3–6 months with regular CD4, CD8 lymphocyte counts and β2 microglobulin levels. At the initiation of the study in January 1992, the HIV-infected patients had already a lower mean CD4 count (360.4 μL−1 versus 658.8 μL−1, P〈0.01), a reversed CD4/CD8 ratio (0.53) and a higher mean serum β2 microglobulin level (1.853 μg mL−1 versus 1.315 μg mL−1, P〉0.05). On regular follow-up, HIV-positive patients had a more significant progressive fall in their mean CD4 count (301.6 μL−1 versus 360.4 μL−1, P〈0.01) and rise in their mean serum β2 microglobulin level (2.60 μg mL−1, versus 1.853 μg mL−1, P〈0.05). The CD4 and CD8 counts of HIV-positive patients were falling at a rate of 1.44 μL−1 month−1 and 4.03 μL−1 month−1 respectively. During the follow-up period, two of the 20 HIV-positive patients developed clinical acquired immunodeficiency syndrome (AIDS) at 15 and 36 months from the initiation of the study. Both patients had typical features of AIDS with a low CD4 count, reversed CD4/CD8 ratio and elevated β2 microglobulin level. The former patient eventually died of fungal brain abscess. The remaining 18 HIV-positive patients so far remained clinically asymptomatic. Eleven patients were put on antiretroviral drug therapy when their CD4 counts fell below 200 μL−1. Only two of the 20 HIV-infected patients developed AIDS during the observation period of 4 years; this figure of 10% is relatively slow. Two of our patients died of AIDS before the study was initiated in 1992. Even if they were included, still only 17.4% had progressed. The figure is in the lowest rate of progression expected from Western experience. Although our study population is small, it remains unclear why our HIV-infected Chinese haemophiliacs have a slow rate of progression to AIDS.