Increased gamma delta T cells in acute Plasmodium falciparum malaria

The T cell receptor of gamma delta is normally expressed on a small percentage of peripheral lymphocytes. Although the role of gamma delta T cells in the physiologic immune response is still unknown, there is accumulating evidence that gamma delta T cells may participate in the immune response to mycobacterial and other infectious organisms. In this study, we have quantitated the number of circulating gamma delta T cells during acute Plasmodium falciparum malaria. The results indicate that gamma delta T cells are elevated during the acute infection and remain elevated for at least 4 weeks during convalescence. T cells may participate in the immune response against P. falciparum by functioning as non-MHC restricted cytotoxic cells against intraerythrocytic parasites. Alternatively, lymphokines may be produced on antigen stimulation which may have antiparasitic activity.     

Lack of correlation between expression of Epstein-Barr virus (EBV) latent membrane protein and bcl-2 oncoprotein in vivo.

AIMS--To evaluate whether there is any correlation between the expression of Epstein-Barr virus (EBV) latent membrane protein (LMP) and oncoprotein bcl-2 in the lymph node biopsy specimens of a Chinese patient with EBV-related reactive lymphoproliferation who later developed T cell lymphoma after a short period of time. METHODS--Immunohistochemistry, with a standard alkaline phosphatase antialkaline phosphatase (APAAP) method and New Fuchsin as a chromogen, was used for single staining of bcl-2 or LMP. Double immunostaining combining APAAP and indirect immunofluorescence was performed for dual labelling of LMP and bcl-2. RESULTS--bcl-2 was expressed in 10-30% of cells in the first lymph node biopsy specimen (EBV-associated lymphoproliferative disorder) and 30-50% of cells in the second lymph node biopsy specimen (T cell lymphoma). LMP was expressed in the first biopsy specimen but not in the second. Double immunostaining results showed that around 78% of LMP positive cells were bcl-2 negative and 94% bcl-2 positive cells were LMP negative. Among the very small fraction of LMP and bcl-2 double positive cells, the intensity of bcl-2 staining was heterogeneous and was not always stronger than that observed in LMP negative bcl-2 positive cells. CONCLUSIONS--The expression of bcl-2 protein is independent of LMP protein status in vivo. Several mechanisms may be involved in EBV associated lymphomagenesis, and bcl-2 induction may occur independently of LMP expression.     

Ovarian serous cystadenoma with mural nodules of genital rhabdomyoma

We present an extremely rare case of ovarian serous cystadenoma with mural nodules of rhabdomyoma. The patient, a 48-year-old woman, was admitted to our hospital with left lower abdominal pain and vaginal bleeding. A unilocular cystic tumor, measuring 13 x 10 x 10 cm, was found in her left ovary and was removed. The tumor contained clear serous fluid, approximately 600 mL, and 2 mural nodules, up to 7.5 x 5.5 x 4.5 cm. The internal cystic wall was thin for the most part and lined with ciliated cuboidal epithelium without any malignant feature. The mural part was composed of mainly more mature muscle fibers with easily discernible cross-striations, set in abundant myxoid to fibromyxoid stroma, similar to clinical and microscopic manifestations of genital rhabdomyomas reported in other sites. Because extracardiac rhabdomyoma has never been described occurring in the ovary, especially arising in serous cystadenoma, to our knowledge, this is the first case reported in the English literature.     

Characterization of cortical neuron outgrowth in two- and three-dimensional culture systems

To improve the ability of regeneration by grafting living cells or by adding growth factor to a lesion site, it is important to find good biomaterials for neuron survival and regeneration. This study focused on two- and three-dimensional cultures in a matrix using biomaterials such as agarose, collagen, fibrin, and their mixtures, because these are considered to be suitable biomaterials for neuron outgrowth. Cortical neurons were dissected from E17 rat embryos and cultured in agarose gel, collagen gel, fibrin glue, and mixtures of collagen and fibrin. Results showed that neurons cultured in collagen gel and fibrin glue had longer periods of survival (more than 3 weeks) and better neurite extension than those observed in agarose gels. As to the survival rate according to the MTT and lactate dehydrogenase assays, fibrin glue was the most suitable biomaterial for neuron survival among the biomaterials examined. With two-dimensional fibrin plating, neuron cells exhibited cell aggregation and stress fibers, but the same results were not observed with collagen gel. There were no differences in neurite extension and survival in the mixtures of collagen and fibrin. The results suggest that collagen and fibrin can provide a suitable substrate for a three-dimensional culture matrix for neuronal survival and differentiation.     

Evaluation of the common conditions associated with eosinophilia.

In an eosinophilic population of 47 boys of the same age, a large proportion (92%) were helminth infested or atopic, or both, compared with 36% of 36 controls. The methods used to detect these conditions were not costly or elaborate, except for the radioallergosorbent test, which was used to measure concentrations of circulating IgE antibodies to atopic allergens. It is suggested that an economical approach to detect helminthiasis and atopy in cases of eosinophilia is adopted using the methods employed here, with skin prick tests replacing the radioallergosorbent test.     

A prospective randomized comparison of levonorgestrel with the Yuzpe regimen in post-coital contraception

A prospective randomized study was conducted at the Family PlanningAssociation of Hong Kong to compare the efficacy of the Yuzperegimen and levonorgestrel (0.75 mg for two doses 12 h apart)in post-coital contraception. A total of 424 subjects were recruitedinto the Yuzpe group and 410 subjects into the levonorgestrelgroup; 77 subjects in the Yuzpe group and 79 subjects in thelevonorgestrel group had further acts of intercourse duringthe treatment cycle. Fifteen pregnancies (3.5%) occurred inthe Yuzpe group and 12 pregnancies (2.9%) in the levonorgestrelgroup. After excluding the patients who had further acts ofintercourse, the failure rates in the Yuzpe group and the levonorgestrelgroup were 2.6 and 2.4% respectively. The incidence of nausea,vomiting and fatigue in the Yuzpe group was significantly higherthan those in the levonorgestrel group. We conclude that levonorgestrelis an effective drug for post-coital contraception with a lowerincidence of side-effects than the Yuzpe regimen.     

Comparison of screening methods for detection of extended-spectrum beta-lactamases and their prevalence among Escherichia coli and Klebsiella species in Hong Kong

Three tests, the disk diffusion test, the double-disc synergy test and the inhibitor-potentiated disc diffusion test, were compared for their abilities to detect production of extended-spectrum beta-lactamases (ESBL) in 702 Escherichia coli and 472 Klebsiella spp. strains from four hospitals. Eleven percent E. coli and 13% Klebsiella spp. were found to produce ESBL. As an indicator of ESBL activity, the sensitivities of the five extended-spectrum beta-lactams were as follows: cefotaxime (100%), cefpodoxime (99.3%), ceftriaxone (98.6%), aztreonam (93%) and ceftazidime (57.7%) when interpreted using the National Committee for Clinical Laboratory Standards criteria. Their positive predictive values ranged from 67.8-83.8%. Both the inhibitor-potentiated disc diffusion test and the double-disc synergy test (at three inter-disc widths of 20, 25 and 30 mm) were capable of identifying all the ESBL-producers. However, at a single inter-disc width of 30 mm, the double-disc synergy test has limited sensitivity (83.8%). As a second test for confirming ESBL activity in strains with reduced susceptibility to beta-lactams, the inhibitor-potentiated disc diffusion test is therefore a simple and reliable option.     

Assessment of HBV persistent infection in an adult population in Taiwan

In order to study the prevalence of hepatitis B virus (HBV) in the adult population of Taiwan, we screened for the presence of HBV DNA in 205 blood samples from adult (20-59-year-old) volunteers. According to the serological markers of HBV, samples were divided into three groups: group I (173 subjects) was negative for both HBsAg and HBeAg; group II (14 subjects) was positive for both HBsAg and HBeAg; and group III consisted of 18 subjects who were HBsAg-positive but HBeAg-negative. Plasma HBV DNA was not detected in group I, but it was found in 85.7% and 11.8% of samples in group II and group III, respectively. A free-form HBV DNA was found in 14.3% of the leukocyte samples in group II. Furthermore, an integrated form of HBV DNA was detected in the leukocytes of two cases of group I who remained healthy based on clinical data. HBV DNA was also detected in the spermatozoa and liver cells of one of the cases.