Serum IgG1 and IgG2 antibody responses to Porphyromonas gingivalis in patients with periodontitis

BACKGROUND/AIMS: Protein and carbohydrate antigens of Porphyromonas gingivalis interact with the host to produce antibody of different subclasses. IgG1 and IgG2 antibodies frequently account for approximately 90% of the total serum IgG. This work aimed to investigate serum IgG1 and IgG2 antibody responses of periodontitis patients to protein and carbohydrate-rich antigens of P. gingivalis. METHODS: Sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blots of P. gingivalis antigens and proteinase K digested antigens rich in carbohydrates were used to investigate the molecular weight of antigen recognised by serum IgG1 and IgG2. Enzyme-linked immunosorbent assay was used to measure levels of IgG1 and IgG2 antibody to P. gingivalis and radial immunodiffusion was used to estimate the total concentration of IgG1 and IgG2 in serum. RESULTS: Serum IgG antibodies bound to antigens of molecular weights 47, 39 and 32 kDa. Antigen most frequently recognised by both IgG1 and IgG2 antibody had a molecular weight of 47 kDa. Serum IgG2 antibody bound to carbohydrate antigen with a molecular weight of 32 kDa but there was no recognition of carbohydrate antigens by IgG1 antibodies. There was no correlation between the titre of anti-P. gingivalis IgG1 or IgG2 antibody and the total concentration of serum IgG1 or IgG2 antibodies of all specificities. CONCLUSION: Both IgG1 and IgG2 antibodies recognised a dominant antigen of 47 kDa, probably Arg-gingipain. Much of the response to carbohydrate antigen is of the IgG2 subclass. Neither the level of IgG1 nor the IgG2 antibody specific to P. gingivalis was related to the total serum concentration of that antibody.     

Detection of epithelial cell transfer in spinal areas by light microscopy and determining any tissue coring via cell culture during combined spinal-epidural interventions

BACKGROUND AND OBJECTIVES: Epithelial tissue coring by spinal needles during subarachnoid injections may cause intraspinal epidermal tumors. Previous studies have investigated tissue transfer with different needle types during subarachnoid or epidural injection. This study deals with the transfer of epithelial tissue during combined spinal-epidural (CSE) anesthesia. METHODS: We studied 68 American Society of Anesthesiologists I to III adult patients. CSE anesthesia was induced under aseptic conditions at the L2-3 or L3-4 interspace with patients in the lateral decubitus position. Cerebral spinal fluid, spinal needle stylet, fluid used to flush the interior of the spinal needle, fluid used to wash the exterior of the spinal needle, fluid used to flush the interior of the epidural needle, and fluid used to wash the exterior tip of the epidural needle were examined under light microscopy (n = 30 patients) or incubated in a cell-culture medium (n = 38 patients). Samples were incubated in cell-culture medium alone (n = 13) or in a cell-culture medium for 3 weeks and then in a medium with epidermal growth factor (n = 25). As a positive control, skin tissue samples were taken by punch biopsy from 10 randomly chosen patients who underwent CSE interventions. These samples were incubated in an enriched medium serum. RESULTS: Light microscopy revealed that there was cell transfer in all phases in various rates: samples 1, 2, 3, 4, 5, and 6 contained epithelial cells and debris in ratios of 6.9%, 20.7%, 6.9%, 20.7%, 26.7%, and 33.3%, respectively. Epithelial cell colonization was detected in the cell-culture samples taken from the control group but not in the samples taken from the CSE group. CONCLUSIONS: We could not reproduce the cells or cell debris obtained during the CSE interventions in vivo, which can be explained by a possible structural deformation of cells or the inadequacy of the amount of cells that were transferred.     

A new nerve-muscle unit model for peripheral nerve studies in rats

Ischiatic, femoral and tibial nerves are commonly utilized in the studies of peripheral nerve surgery in rats. The authors present a new nerve-muscle unit model in which the nerve is distal enough to minimize morbidity and the muscle is convenient for all electromyographic studies. Twenty-five Wistar-Albino rats were used. In the control group; normal electromyography and histology were demonstrated in the lateral tibial nerve (LTN) and in the flexor digiti quinti brevis (FDQB) muscle. In experimental group I; a 0.5 cm nerve gap was made in the LT nerve and the proximal end was buried in the muscle in order to prevent reinnervation. In experimental group II, the LTN was cut and repaired primarily. In both groups I and II, electromyographic and histologic studies were performed at 6 and 12 weeks. In study group I, atrophic and degenerative findings were observed and in study group II, only regenerative findings were observed. The authors concluded that the LT nerve-FDQB muscle unit is a convenient model for peripheral nerve studies, with the advantages of easy dissection, wide exposure, and minimal morbidity. This model is also convenient for electromyographic and histologic evaluation.     

Late-term reconstruction of lateral ankle ligaments using a split peroneus brevis tendon graft (Colville's technique) in patients with chronic lateral instability of the ankle

We reviewed 14 patients with chronic lateral instability of the ankle treated by Colville's technique between 1996 and 2001. The mean patient age was 25 (20-35) years and all were men. The mean period between injury and surgery was 25 (18-32) months, and the mean follow-up was 20 (14-32) months. Twelve of the results were excellent and two were good according to the criteria of Chrisman and Snook. All patients returned to normal daily activity levels at an average of 6 months following surgery.     

Do perceived health risks outweigh the benefits of modern contraceptives? A qualitative study in a suburban population in Istanbul, Turkey.

OBJECTIVES: To evaluate the health concerns and the perceived non-contraceptive benefits of modern contraceptive methods through utilizing qualitative methods. METHODS: Six focus group discussions were carried out with a total of 53 married women in a socio-economically disadvantaged community in Istanbul, Turkey. RESULTS: Women had a vague knowledge of the mechanism of menstruation. Some women believed that the uterus was filled with blood -- termed 'dirty blood' -- which should be eliminated during menstruation in order to stay healthy. For this reason, amenorrhoea was recognized as the important disadvantage of the progestin-only injectable contraceptives. While the participants mentioned fallacious and exaggerated side effects related to modern methods they did not recognize their non-contraceptive benefits. Most women gained the information concerning side effects through their social networks. Sometimes the information acquired was based on rumours that biased women against the modern contraceptives. CONCLUSIONS: Women outweighed the risks, some of which were fallacious and exaggerated, against the benefits of modern contraceptives. It is crucial to address health concerns of women and what they 'heard' from their peers during counselling sessions. Also the non-contraceptive health benefits of modern methods should be well emphasized. Since informal sources are prevalent, the effectiveness of peer education should be studied in this community.