Mononucleosis syndrome and coincidental human herpesvirus-7 and Epstein-Barr virus infection

Two girls (a 5 year old and a 21 month old) experiencing mononucleosis syndrome with coincidental human herpesvirus (HHV)-7 and Epstein-Barr virus (EBV) infections are described. One patient had primary HHV-7 infection and reactivated EBV infection. The other had primary HHV-7 and EBV infections. These cases indicated that HHV-7 is capable of inducing infectious mononucleosis-like illness. Multiple herpesvirus infection in one of the patients also suggests that interaction among herpesviruses can occur in vivo. The consequence of this interaction may have clinical implications.     

Thyroid dysfunction after mantle irradiation of Hodgkin's disease patients

Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated.     

Nitric oxide, microglial activities and neuronal cell death in the lateral geniculate nucleus of glaucomatous rats

The present study was initiated to investigate neuronal degeneration, microglial reactivity and possible roles of NO in the lateral geniculate nucleus (LGN) of glaucomatous rats. An experimental one-eye glaucoma model was created by cauterization of the limbal-derived veins. Neuronal cell viability was studied by immunostaining with antibody against neuronal nuclei. Changes of expressions of nitric oxide synthase I (NOS I), NOS II, ED 1, OX6 and OX42 in the LGN were studied by immunohistochemistry. NADPH-d histochemistry was also employed. In the experimental glaucomatous rats, the number of NeuN labelled neurons was significantly decreased in both the ipsi- and contra-lateral sides of the ventral LGN (vLGN) but not the dorsal LGN (dLGN) at 1 month post-operation and beyond. Expressions of NOS I and NADPH-d were notably increased from 1 week post-operation in the ipsilateral vLGN. In the contralateral side of the vLGN, however, this change was only observed from 1 month post-operation. No NOS II immunoreaction was observed in LGN of both the normal control and glaucomatous rats. Increased microglial reactivity as indicated by OX-42 immunoreactivity was first observed in both sides of the LGN at 1 week post-operation, and this was most significant especially at 1 and 2 months post-operation. The present results suggest that NO and microglial cells may play some important roles in the pathologic processes of neuronal degeneration in the LGN of glaucomatous rats.     

Quantitative computer‐assisted digital‐imaging upper airway analysis for obstructive sleep apnoea*

This was a prospective study of a new objective method which quantitatively analyses the upper airways in patients with obstructive sleep apnoea (OSA). Video‐nasopharyngoscopic examinations of the upper airways of 45 patients were carried out with an endoscopic calibrator. Images of the upper airway during quiet respiration and Mueller's manoeuvre in erect and supine positions were digitized by computer to generate the actual dimensions of obstructive sites. Measurements by the new method were validated by comparing 90 pairs of videoendoscopic images with upper airway magnetic resonance imaging (MRI) measurements at two identical levels. Quantitative precision is 100% for the retropalatal level and 95.6% for the retrolingual level with a tolerance of 0.5 cm² between the two methods. The absolute mean of the difference between the two methods of measurement is 0.08 cm² at the retropalatal level and 0.18 cm² at the retrolingual level. The agreement between the digital‐imaging videoendoscopic and MRI measurements was 93.3% for the retropalatal level and 95.6% for the retrolingual level. Quantitative computer‐assisted digital imaging is a reliable, cost‐effective clinical method of upper airway evaluation in OSA patients. This method allows us to examine the dynamic and static morphology objectively, measure surgical outcomes of upper airway, opening up new avenues for OSA management.     

DNA vaccination using bacillus Calmette-Guerin-DNA as an adjuvant to enhance immune response to three kinds of swine diseases

In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin （BCG）-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease （FMD）, Aujeszky＇s disease （AID） and classical swine fever （CSF）. BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines （pVSG, pVgD and pVE2） against the respective infection were constructed, and BCGDNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin （Ig）G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice （P〈0.01）. Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups （P〈0.01）. Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups （P〈0. 05）. Whereas interleukin-4, humoral immune cytokine, was not significant （P〉 0. 05）. These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity.     

Attempted suicide and polymorphism of the serotonin transporter gene in Chinese patients with schizophrenia

Abnormalities of serotonin synthesis and metabolism may be associated with suicidality. The serotonin transporter gene (5-HTT) is one of the important genes involved in the regulation of serotonin neurotransmission. We examined the association of suicidal behavior in Chinese schizophrenic patients with a functional polymorphism of the promoter region of the 5-HTT gene (5-HTTLPR). The 5-HTTLPR genotype was determined by polymerase chain reaction for 76 suicidal and 262 non-suicidal patients with a diagnosis of schizophrenia (DSM-IV criteria). All subjects were unrelated to each other, and all were Chinese. There was no significant genotypic or allelic association of the 5-HTTLPR polymorphism with history of attempted suicide. From our results, this 5-HTTLPR polymorphism is unlikely to have a major effect on suicidal behavior in Chinese patients with schizophrenia.     

Contrast column interruption artefact in computed tomography pulmonary angiography

Interruption of the contrast column during inspiration can lead to non‐diagnostic CT pulmonary angiograms. The importance of this artefact will increase with more CT studies being performed for pulmonary embolism on multidetector row CT. We describe here an instance of such an artefact and discuss its aetiology.