A survey of coxsackie A16 virus antibodies in human sera

A comparison of neutralizing and immunofluorescent (IF) IgG antibody tests in 18 sera from 10 cases of hand, foot and mouth disease (HFMD) showed a variety of responses but all sera taken more than one week after infection had both neutralizing and IF IgG antibodies. A survey of IF IgG antibody in 80 paediatric and 80 adult non-HFMD case sera gave antibody detection rates of 47.5% and 11.3% respectively. This difference could be attributed to a decline in IF IgG antibody with time after infection. Three point nine per cent of 26 sera from possible adult carditis cases had IF antibody suggesting that coxsackie A16 virus was not a common cause of adult carditis. Forty-eight point three per cent of 29 sera from cases of spontaneous abortion had detectable IF antibody, a rate similar to the paediatric sera and significantly greater than that in adult male (7.9%) and other adult female (13%) sera tested. This interesting observation requires further study.     

The nature of immunosuppression in Trypanosoma brucei infections in mice: I. The role of the macrophage

The functional integrity of the mononuclear phagocytic system (MPS) in mice infected with Trypanosoma brucei was investigated with regard to its possible significance in the aetiology of the immunosuppression characteristic of this disease.

In infected mice the spleens and lymph nodes were grossly enlarged, and on histological examination it was shown that the MPS of the liver, lymph nodes, spleen and bone marrow was markedly expanded. Macrophages presented an active appearance and often contained cellular debris. Clearance of intravenously injected sheep red blood cells (SRBC) was increased, in that 1 hour after injection, 2–6 times more ⁵¹Cr-labelled SRBC had disappeared from the circulation of infected, compared to uninfected mice; this was due largely to an increased uptake by the expanded phagocytic system of the liver.

The intrinsic immunogenic potential of individual macrophages appeared to be unimpaired as judged by the ability of SRBC-containing macrophages from infected mice to elicit a response in syngeneic normal recipient mice.

It was concluded that the only evidence that immunosuppression might be associated with an altered activity of the MPS was an increased hepatic uptake of particulate antigen with a relative failure of splenic uptake. Together these might be responsible for a reduction in the concentration of antigen in the tissues of an enlarged spleen below the level necessary to initiate the formation of antibody.

     

Modelling the association between adherence and viral load in HIV-infected patients

The primary objective of this paper is to investigate the effect of adherence to prescribed antiretroviral therapy on virologic response measured repeatedly over time in HIV-infected patients. To this end observations on plasma viral load (HIV RNA) assessed in copies/ml are categorized into four clinically meaningful states, [0--50[, [50--400[, [400--2000[, [2000 and up. A time-dependent continuation ratio model is used to analyse longitudinal ordinal responses. The main challenge lies in modelling dependencies over time and using information contained in the data efficiently to establish a dynamic relation between observed patient adherence and viral load. Among the several measures of adherence investigated, two specifically account for long periods of time without intake. One is derived from the third moment of the inter-dose interval distribution, while the second reflects internal drug exposure using pharmacokinetic parameters. The approach is applied to a clinical trial involving 35 patients who were followed over 12 months. Results demonstrate a significant relation between patient adherence and virologic response.     

Postural activity of the abdominal muscles varies between regions of these muscles and between body positions

The abdominal muscles have an important role in control and movement of the lumbar spine and pelvis. Given there is new evidence of morphological and functional differences between distinct anatomical regions of the abdominal muscles, this study investigated whether there are regional differences in postural activity of these muscles and whether recruitment varies between different body positions. Eleven subjects with no history of low back pain that affected function or for which they sought treatment participated in the study. Electromyographic (EMG) activity of the upper, middle and lower regions of transversus abdominis (TrA), the middle and lower regions of obliquus internus abdominis (OI) and the middle region of obliquus externus abdominis (OE) was recorded using intramuscular electrodes. All subjects performed rapid, unilateral shoulder flexion in standing and six subjects also moved their upper limb in sitting. There were regional differences in the postural responses of TrA with limb movement. Notably, the onset of EMG of the upper region was later than that of the lower and middle regions. There were no differences in the EMG onsets of lower and middle TrA or OI. The postural responses of the abdominal muscles were also found to differ between body positions, with recruitment delayed in sitting compared to standing. This study showed that there is regional differentiation in TrA activity with challenges to postural control and that body position influences the postural responses of the abdominal muscles. These results may reflect variation in the contribution of abdominal muscle regions to stability of the trunk.     

Flexion contracture after total knee arthroplasty in a patient with Parkinson's disease: successful treatment with botulinum toxin type A

The few reports in the orthopedic literature that discuss outcomes after total knee arthroplasty in patients with Parkinson's disease cite mixed results. These patients are at increased risk for the development of flexion contracture, which has been shown to significantly worsen functional scores. The present report describes the development of a flexion contracture in a patient with Parkinson's disease after total knee arthroplasty. This contracture was successfully treated with manipulation under anesthesia and injections of botulinum toxin type A into the hamstring and gastrocnemius muscles, in conjunction with a static progressive extension orthosis and rigorous physical therapy.