Qualitative analysis of neck kinematics during low-speed rear-end impact

OBJECTIVE

To analyze neck kinematics and loading patterns during rear-end impacts.

DESIGN

The motion of each cervical vertebra was captured using a 250 frame/s X-ray system during a whole body rear-end impact. These data were analyzed in order to understand different phases of neck loading during rear-end impact.

BACKGROUND

The mechanism of whiplash injury remains largely unknown. An understanding of the underlying kinematics of whiplash is crucial to the identification of possible injury mechanisms before countermeasures can be designed.

METHODS

Metallic markers were inserted into the vertebral bodies and spinous processes of each of the seven cervical vertebrae. Relative displacement-time traces between each pair of adjacent cervical vertebrae were calculated from X-ray data. Qualitative analyses of the kinematics of the neck at different phase of impact were performed.

RESULTS

The neck experiences compression, tension, shear, flexion and extension at different cervical levels and/or during different stages of the whiplash event.

CONCLUSIONS

Neck kinematics during whiplash is rather complicated and greatly influenced by the rotation of the thoracic spine, which occurs as a result of the straightening of the kyphotic thoracic curvature.

RELEVANCE

Understanding the complicated kinematics of a rear-end impact may help clinicians and researchers shed some light on potential mechanisms of whiplash neck injury.

Kinematics of human cadaver cervical spine during low speed rear-end impacts

The purposes of this study were to measure the relative linear and angular displacements of each pair of adjacent cervical vertebrae and to compute changes in distance between two adjacent facet joint landmarks during low posterior-anterior (+Gx) acceleration without significant hyperextension of the head. A total of twentysix low speed rear-end impacts were conducted using six postmortem human specimens. Each cadaver was instrumented with two to three neck targets embedded in each cervical vertebra and nine accelerometers on the head. Sequential x-ray images were collected and analyzed. Two seatback orientations were studied. In the global coordinate system, the head, the cervical vertebrae, and the first or second thoracic vertebra (T1 or T2) were in extension during rear-end impacts. The head showed less extension in comparison with the cervical spine. Relative motion for each cervical motion segment went from flexion at the upper cervical levels to extension at the lower cervical levels, with a transition region at the mid-cervical levels. This rotational pattern formed an "S" shape in the cervical spine during the initial phase of low-speed rear impacts. A pair of facet joint landmarks on each cervical motion segment was used to measure the distance across the joint space. Uni-axial facet capsular strains were calculated by dividing changes in this distance over the original distance in seven tests using three specimens. In 20-degree seatback tests, the average strain was 32+/-11% for the C2/C3 facet joint (17%-43% range), and 59+/-26% for the C3/C4 facet joint (41%-97% range). The C4/C5 and C5/C6 facet joints exhibited peak tensile or compressive strains in different specimens. In 0-degree seatback tests, the average strain was 28+/-11% for the C2/C3 facet joint (21%-41% range), 30+/-9% for the C3/C4 facet joint (21%-39% range), 22+/-4% for the C4/C5 facet joint (19%-25% range), and 60+/-13% for the C5/C6 facet joint (51%-69% range). In 20-degree seatback tests, there was less initial cervical lordosis, more upward ramping of the thoracic spine, and more relative rotation of each cervical motion segment in comparison with the 0-degree seatback tests. Relative to T1, the head went from flexion to extension for 20-degree seatback tests while stayed in extension for 0-degree seatback tests.

Immunotactoid glomerulopathy associated with idiopathic hypereosinophilic syndrome

A case of immunotactoid glomerulopathy in an 18-year-old man with an idiopathic hypereosinophilic syndrome is presented. The patient showed cervical lymphadenopathy, asymptomatic proteinuria of nephrotic range, and hematuria without any defined immunologic disease. Marked and prolonged hypereosinophilia was found in peripheral blood (eosinophil count; 6,248/mm3) and bone marrow (eosinophil series; 32%). Diffuse and/or nodular eosinophilic infiltration was identified in multiple organs such as kidney, stomach, liver, lymph node, and skin. Renal biopsy revealed endocapillary proliferative features of typical immunotactoid glomerulopathy with IgG and C3 deposition and microtubular structures of variable size, 20-80 nm in diameter, mainly in the subendothelium. This study suggests that immunotactoid glomerulopathy may be a secondary immunologic manifestation of the tissue damage by eosinophils in the idiopathic hypereosinophilic syndrome.

Association study of a functional serotonin transporter gene polymorphism with schizophrenia, psychopathology and clozapine response

Serotonin is implicated in the pathogenesis of schizophrenia. Following serotonin release, the serotonin transporter (5-HTT) is the major determinant of serotonin inactivation. The present study tested the hypothesis that a biallelic polymorphism in the 5' regulatory region of the 5-HTT gene (5-HTTLPR) confers susceptibility to schizophrenia, association with the clinical manifestations of schizophrenia or clozapine response. 90 treatment-resistant schizophrenic patients were assessed using the Brief Psychiatric Rating Scale before and after clozapine treatment. The results demonstrated that the 5-HTTLPR variants did not play a major role in the susceptibility, clinical manifestations or clozapine response in schizophrenia.

[Bibliometric analysis on tissue engineering research literatures]

OBJECTIVE

To comprehend the progress of tissue engineering research and speculate its developmental trends.

METHODS

MEDLINE search was conducted to retrieve the papers published between 1987 to 1999 under the main headings of tissue engineering. Years, nationalities, languages, journals, authors and heading frequencies of 314 papers were analyzed by bibliometrics.

RESULTS

Since 1990, the number of tissue engineering research literatures had doubled, and papers between 1998 and 1999 made up 57.96% of the total papers. All papers came from 15 nations, in 6 languages and 140 journals; 64.97% came from United States and 25.79% from England, Netherlands and Germany; 93.95% was in English; 42.04% was published on 15 journals. Vacanti JP and 19 other authors presented 5 to 24 papers. Heading frequencies were cytology 22.89%, transplantation 13.30%, scaffolds and extracellular matrixes 11.72%, implanting 10.60%, polymers 8.91%, potential applications 8.91%, artificial substitutes 6.88%, tissue culture 6.70% and biogenetics 4.96%.

CONCLUSION

Tissue engineering literatures mainly come from United States, England, Netherlands and Germany. English is the major language. J Biomed Mater Res and 14 other journals are important journals about tissue engineering research. Vacanti JP and 19 other authors are prolific authors. Cytology, transplantation, scaffolds and extracellular matrixes and implanting are hot topics and key points on tissue engineering research.

2-Amino-3-methylimidazo[4,5-f]quinoline inhibits nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells by blocking p38 kinase activation

We show that 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), a heterocyclic amine, significantly inhibits nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophages. The decrease in NO production was found to correlate well with a decrease in inducible NO synthase (iNOS) mRNA expression as demonstrated by Northern blot analysis. Treatment of RAW 264.7 cells with IQ selectively inhibited the activation of NF-kappaB/Rel, an important transcription factor of iNOS gene expression, while neither AP-1 nor Oct was affected by IQ. Since iNOS transcription has been shown recently to be under the control of the p38 kinase signaling cascade, we assessed the effect of IQ on p38 kinase activation. Treatment of RAW 264.7 with IQ inhibited LPS-stimulated p38 kinase phosphorylation in a dose-related manner. IQ also inhibited the p38 kinase activity. Collectively, this series of experiments indicates that IQ inhibits LPS-induced expression of iNOS gene in RAW 264.7 cells. Based on our findings, the most likely mechanism that can account for this biological effect involves the negative regulation of NF-kappaB/Rel and p38 kinase pathway.

Dexamethasone inhibits IL-1 beta gene expression in LPS-stimulated RAW 264.7 cells by blocking NF-kappa B/Rel and AP-1 activation

In the present study, the mechanism by which dexamethasone (DEX) inhibited IL-1beta gene expression in bacterial lipopolysaccharide (LPS)-activated RAW 264.7 cells was investigated. The decrease in LPS-induced IL-1beta mRNA expression was demonstrated by quantitative reverse transcription polymerase chain reaction (RT-PCR). Since the promoter in IL-1beta gene contains binding motifs for NF-kappaB/Rel, AP-1, NF-IL6, and CREB/ATF, which appear to be important in LPS-mediated IL-1beta induction, the effects of DEX on the activation of these transcription factors were examined. Treatment of DEX to RAW 264.7 cells induced a dose-related inhibition of NF-kappaB/Rel and AP-1 in chloramphenicol acetyltransferase activity, while neither NF-IL6 nor CREB/ATF activation was affected by DEX. Treatment of RAW 264.7 cells with DEX inhibited DNA binding of NF-kappaB/Rel and AP-1 proteins to their cognate DNA sites as measured by electrophoretic mobility shift assay (EMSA). DEX treatment caused a significant reduction in nuclear c-rel, p65, and p50 protein contents, and these decreases were paralleled by the accumulation of cytoplasmic c-rel, p65, and p50. DEX treatment of RAW 264.7 cells did not inhibit the nuclear translocation of c-jun and c-fos. We found that the inhibition of IL-1beta production by DEX is not related to p38, which is important in the IL-1beta induction. These results suggest that DEX may inhibit IL-1beta gene expression by a mechanism involving the blocking of LPS-induced NF-kappaB/Rel and AP-1 activation.

Chlorophyllin suppression of lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells

Chlorophyllin (CHL), a water-soluble derivative of chlorophyll, functions as an anticarcinogen and antioxidant. In the present study, we investigated the effect of CHL on nitric oxide production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Treatment with CHL inhibited nitric oxide production in the LPS-stimulated RAW 264. 7 cells in a dose-related manner. Competitive RT-PCR analysis, using a DNA competitor as an internal standard, demonstrated that the treatment with 1, 10, and 50 microM CHL decreased LPS-induced iNOS mRNA expression in a concentration-dependent manner. Since the expression of the iNOS gene is mainly regulated by NF-kappaB, we then examined the effects of CHL on the NF-kappaB DNA binding activity, using an electrophoretic mobility shift assay. CHL down-regulated the NF-kappaB DNA binding on its cognate recognition site at the concentrations just noted. Employing a transfection and reporter gene expression system with p(NF-kappaB)(3)-chloramphenicol acetyl transferase (CAT), the treatment of CHL produced a dose-dependent inhibition of CAT activity in RAW 264.7 cells. Furthermore, CHL partially restored LPS-decreased IkappaBalpha, an inhibitory protein against NF-kappaB activation, in the cytosolic extract from the LPS-treated cells determined by immunoblot analysis. CHL also protected the hydroxyl radical-induced cytotoxicity in RAW 264.7 cells, indicating its antioxidant effect. These results suggest that CHL suppresses the nitric oxide production and iNOS mRNA expression mediated by the inhibition of NF-kappaB activation, and its action mechanism may be based on its antioxidant effect.

Limiting donor site morbidity by suprafascial dissection of the radial forearm flap

A technique of suprafascial flap elevation to prevent donor site problems is described, based on careful intraoperative observation of the anatomical relations of all involved structures in a series of over 400 free forearm flaps used in various reconstructive procedures.

Inconsistency between severe substantia nigra degeneration with Lewy bodies and clinical parkinsonism in dementia patients: a cliniconeuropathological study

In a retrospective cliniconeuropathological study, we reviewed all the cases received in our dementia brain bank during a 4-year period to determine if all patients with severe substantia nigra (SN) degeneration and SN Lewy bodies (LBs) exhibited prominent signs of parkinsonism and were treated for parkinsonism during the disease course. The SN of 426 cases were graded for microscopic degeneration using a semiquantitative five-tiered scale, with grade 0 indicating normal and grade 4 the most severe degeneration. Twenty-nine cases with grade 3 (16) or grade 4 (13) SN degeneration with SN LBs and clinical records were identified. Ten had been treated for parkinsonism (6 grade 3, 4 grade 4) and 19 had not. Whereas most of the patients had exhibited signs of end-stage parkinsonism during their last year, 1 grade 3 and 2 grade 4 patients apparently never exhibited prominent signs of parkinsonism during the course of their dementia. No clear neuropathological differences were noted between these patients that did not have prominent signs and a control group of six patients with clinical Parkinson's disease with dementia (parkinsonism onset at least 1 year before dementia onset). We conclude that in patients with dementia there is an inconsistent relationship between the expression of clinical parkinsonism during life and severe SN degeneration with LBs identified at necropsy.

Suppression of IL-2 and IL-4 gene expression by nodularin through the reduced NF-AT binding activity

Nodularin is a cyclic peptide produced by cyanobacteria. In the present study, the inhibitory effect of nodularin on T lymphocyte functions was demonstrated. Direct addition of nodularin to B6C3F1 mouse splenocyte cultures produced a concentration-dependent inhibition of the lymphoproliferative response to concanavalin A stimulation. Nodularin inhibited PMA plus ionomycin (Io)-induced IL-2 mRNA expression in murine splenocytes and thymocytes as determined by quantitative/competitive RT-PCR. To further characterize the mechanism for the transcriptional regulation of IL-2, the binding activity of transcription factors, NF-AT, AP-1, NF-kappaB, and Oct, was evaluated by electrophoretic mobility shift assays in mouse splenocytes. Nodularin reduced the NF-AT binding activity in PMA/Io-induced splenocytes, but no significant effect was observed on AP-1, NF-kappaB, or Oct binding activity. Nodularin also inhibited IL-4 mRNA expression in PMA/Io-stimulated murine splenocytes. These results suggest that T lymphocyte is a possible cellular target of nodularin, and the inhibitory effect of nodularin on T-cell specific transcription factor NF-AT induces T-cell dysfunction, which leads to a diminution in IL-2 and IL-4 gene transcription.

2-Acetylaminofluorene suppresses immune response through the inhibition of nuclear factor-kappaB activation during the early stage of B cell development

2-Acetylaminofluorene (AAF), an arylamide carcinogen, has been known to inhibit humoral and cell-mediated immune response by lipopolysaccharide (LPS). In the current study we demonstrate that AAF induced the down-regulation of protein kinase C (PKC) that is a key enzyme in the pathways leading to LPS-induced B-cell proliferation, while having no inhibitory effect on intracellular cAMP in spleen cells. Additionally, to identify the mechanism of action of AAF during B-cell development, we determined the effects of AAF on LPS-induced nuclear factor-kappaB (NF-kappaB) activation in 70Z/3 murine pre-B cells, CH12 murine mature B cells and S194 murine plasmacytoma cells. LPS-induced NF-kappaB activation, which is dependent on PKC, was inhibited by pretreatment with AAF for 2 h in the nuclei of 70Z/3 murine pre-B cells by detection of NF-kappaB specific DNA-protein binding. Conversely, AAF barely inhibited the constitutive NF-kappaB binding activity in mature B-cells, S194 and CH12. To confirm the effect of AAF on NF-kappaB activation, a chloramphenicol acetyl transferase (CAT) expression vector containing multiple copies of the NF-kappaB element (pCAT(kappaB)(3)) was transiently transfected into 70Z/3 or S194 cells, and assessed for inducible CAT activity. AAF treatment of 70Z/3 cells resulted in a significant inhibition of CAT activity induced by LPS. However, AAF exhibited no inhibitory effect on constitutive CAT activity in mature B cells, S194, indicating that AAF no longer has suppressive effects on the immune response in differentiated B cells. Taken together, these results suggest that AAF may act to suppress immune response by blocking the activation of PKC and nuclear expression of NF-kappaB at the early stage of B cell development.

Role of nuclear factor of activated T-cells and activator protein-1 in the inhibition of interleukin-2 gene transcription by cannabinol in EL4 T-cells

We previously reported that immunosuppressive cannabinoids inhibited interleukin (IL)-2 steady-state mRNA expression and secretion by phorbol-12-myristate-13-acetate plus ionomycin-activated mouse splenocytes and EL4 murine T-cells. Here we show that inhibition of IL-2 production by cannabinol, a modest central nervous system-active cannabinoid, is mediated through the inhibition of IL-2 gene transcription. Moreover, electrophoretic mobility shift assays demonstrated that cannabinol markedly inhibited the DNA binding activity of nuclear factor of activated T-cells (NF-AT) and activator protein-1 (AP-1) in a time- and concentration-dependent manner in activated EL4 cells. The inhibitory effects produced by cannabinol on AP-1 DNA binding were quite transient, showing partial recovery by 240 min after cell activation and no effect on the activity of a reporter gene under the control of AP-1. Conversely, cannabinol-mediated inhibition of NF-AT was robust and sustained as demonstrated by an NF-AT-regulated reporter gene. Collectively, these results suggest that decreased IL-2 production by cannabinol in EL4 cells is due to the inhibition of transcriptional activation of the IL-2 gene and is mediated, at least in part, through a transient inhibition of AP-1 and a sustained inhibition of NF-AT.

Endoscopic bone graft for delayed union and nonunion

We performed endoscopic bone grafting for eight patients of delayed union and nonunion which developed after femoral and humeral shaft fractures. The mean interval from initial intervention to endoscopic bone grafting was 7.3 months. Six patients of delayed union and nonunion healed at 4.1 months on average. Two patients had unsatisfactory healing and eventually underwent non-endoscopic revisional surgery. There was no intraoperative on postoperative complication. Endoscopic bone grafting can be a less invasive alternative, obtaining rapid bone union in cases of compromised healing of the diaphyseal fracture.

Removal of the deeply inserted proximal interlocking screw in the greater trochanter after femoral nailing

Removal of the proximal interlocking screw (PIS), especially one that is deeply inserted in the greater trochanter or covered by heterotopic ossification, is troublesome and requires considerable effort because the search for its head usually requires removing bone from around the insertion site. We introduce a simple tip to remove this complicated PIS with the aid of a proximal drill guide, drill bit, and AO countersink.

Suppression of the interleukin-2 gene expression by aflatoxin B1 is mediated through the down-regulation of the NF-AT and AP-1 transcription factors

The effect of aflatoxin B1 (AFB1) on the interleukin-2 (IL-2) gene expression was investigated in thymocytes of B6C3F1 mice, Jurkat E6-1 human T-cell leukemia, and EL4.IL-2 murine thymoma. AFB1 inhibited the phorbol-12myristate-13-acetate/i6nomycin (PMA/Io)-induced IL-2 mRNA expression in the murine thymocytes and Jurkat E6-1 cells as determined by qualitative RT-PCR, while no effect was observed in the EL4.IL-2 cells. Electrophoretic mobility shift assay indicated that AFB1 treatment showed an inhibition of the NF-AT and AP-1 DNA binding in PMA/Io-stimulated thymocytes and Jurkat E6-1 cells. No effect was observed on the Oct and NF-kappaB DNA binding. Employing a reporter gene expression system with p(NF-AT)3-CAT and p(AP-1)3-CAT, treatment with AFB1 to the transfected Jurkat E6-1 cells also showed an inhibition of the PMA/Io-induced NF-AT/CAT and AP-1/CAT activities. These results suggest that suppression of the IL-2 gene expression by AFB1 is mediated through the down-regulation of the NF-AT and AP-1 activation.

Performance, serum characteristics, carcase traits and lipid metabolism of broilers as affected by supplement of chromium picolinate

1. This study investigated the effects of dietary supplementation with chromium picolinate on the performance, serum and carcase traits and lipid metabolism of broilers. In trial 1, 120 1-day-old broilers with an equal number of males and females were assigned at random to 4 groups with 3 replicates. Four treatments with dietary supplements of 0 (control), 800, 1600 and 3200 microg/kg of chromium picolinate were used. In trial 2, 6-week-old broilers (20) were used to determine how supplements of 0, 200, 400 and 800 microg/kg chromium in an incubation medium influence their hepatocyte lipogenic capacity and adipocyte lipolysis, in vitro. 2. Dietary supplements of 1600 and 3200 microg/kg chromium in broiler diets significantly increased food consumption (P<0.05); 1600 microg/kg markedly improved weight gain (P<0.05); 1600 and 3200 microg/kg groups showed increased liver lipid content (P<0.05). However, the abdominal fat content tended to decrease in these 2 groups. 3. Dietary supplements of 1600 and 3200 microg/kg of chromium decreased serum glucose and nonesterified fatty acids (NEFA) concentrations while increasing serum phospholipid content (P<0.05). Insulin concentration decreased only in birds receiving 3200 ppb chromium (P<0.05). Serum triacylglycerol (TG) clearance rate in chromium-supplemented groups was markedly enhanced (P<0.05). 4. In addition, chromium supplemented groups had increased serum HDL contents and also reduced serum VLDL and LDL contents (P<0.05). 5. Trial 2 indicated that lipogenesis from [U-14C]glucose by isolated hepatocytes was significantly enhanced by 400 ppb chromium (P<0.05). 6. The results from this study demonstrate that a supplement of 1600 microg/kg of chromium picolinate in the ration influences the growth, carcase, serum traits and lipid metabolism of broilers.

Serotonin-6 receptor variant (C267T) and clinical response to clozapine

Clozapine is an effective atypical antipsychotic that has high affinity for serotonin type 6 receptors (5HT6). We tested the hypothesis that clinical response to clozapine in patients refractory to typical antipsychotic treatment is related to the genetic variant (C267T) of the 5HT6 receptors. Ninety-nine schizophrenic patients with a history of non-response to typical antipsychotics were included in the study. The results demonstrated a modest but significant relationship between presence of the variant of the 5HT6 receptors and the response to clozapine in these patients. Patients with homogenous 267T/T genotype had a better response than other patients. Although replication is required, these results suggest that the 5HT6 receptor C267T polymorphism may be involved in clozapine response, especially in patients with anxious or depressed symptoms.

Endoscopic bone graft for delayed union and nonunion

Nonunion and delayed union are serious consequences in the treatment of fractures. Bone graft has been a mainstay of treatment for nonunion and delayed union. But with rapid development of the endoscopic procedure, bone grafting can be performed after curettage of fibrous tissue around the fracture gap and sclerotic fracture end under direct visual control of the endoscope. This technical note provides procedures for this technique.

Acetylaminofluorene inhibits nitric oxide production in LPS-stimulated RAW 264.7 cells by blocking NF-kappa B/Rel activation

The mechanism by which 2-acetylaminofluorene (AAF) inhibited nitric oxide (NO) formation, in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells was investigated. The decrease in NO, as demonstrated by measurement of nitrite was found to correlate well with a decrease in inducible nitric oxide synthase (iNOS) mRNA. Since the promoter in iNOS gene contains binding motifs for NF-kappa B/Rel, AP-1, and NF-IL6 which appear to be important for LPS-mediated iNOS induction, the effect of AAF on the activation of these transcription factors was determined. Treatment of AAF to RAW 264.7 cells induced a dose-related inhibition of NF-kappa B/Rel in chloramphenicol acetyltransferase activity, while either AP-1 or NF-IL6 activation was not affected by AAF. Treatment of RAW 264.7 cells with AAF inhibited protein/DNA binding of NF-kappa B/Rel to its cognate site as measured by electrophoretic mobility shift assay. In addition, AAF treatment caused a significant reduction of nuclear c-rel, p65, and p50 protein levels, and this decrease was paralleled by the accumulation of cytoplasmic c-rel, p65, and p50. These data suggest that AAF inhibits iNOS gene expression by a mechanism involving a blockade of LPS-induced nuclear translocation of NF-kappa B/Rel.

The inhibitory effect of polysaccharides isolated from Phellinus linteus on tumor growth and metastasis

It was previously reported that polysaccharides (PL) isolated from Phellinus linteus strongly stimulated cell-mediated and humoral immunity. This study was undertaken to investigate the immunochemotherapeutic activity of PL against tumor growth and metastasis. PL alone significantly prolonged the survival rate of B16F10-implanted mice, inhibited tumor growth in NCI-H23-implanted nude mice, and reduced the frequency of pulmonary metastasis of B16F10 melanoma. Adriamycin significantly inhibited tumor growth, but only slightly inhibited metastasis. The combination therapy with PL and adriamycin was more effective in inhibiting tumor growth, but not metastasis. PL did not induce direct toxicity in cancer cells, which is characteristic of immunotherapeutics. In conclusion, PL might be of use in immunochemotherapy of cancer because of its effective activities on tumor growth and metastasis through the immunopotentiation of the patients without toxicity.

Subcutaneous sacrococcygeal myxopapillary ependymoma

We report a case of myxopapillary ependymoma presenting as a primary tumor of the subcutaneous tissue in the sacrococcygeal region. The mass was large, well-encapsulated, lobulated, and multiseptated, with varying signal intensity on T1- and T2-weighted MR images caused by hemorrhagic necrosis, blood degradation products, and calcification. Only a small viable portion enhanced after administration of contrast material. Multiple lobules formed from fibrous septa and dystrophic calcification also characterize this tumor.

No evidence for association of serotonin-2A receptor variant (102T/C) with schizophrenia or clozapine response in a Chinese population

The serotonin hypothesis in schizophrenia had regained interest with the superior efficacy of clozapine in the refractory schizophrenic patients. Among the serotonin receptors, the serotonin 2A (5HT2A) receptor subtype is the most widely studied. Previous studies on the association between a silent mutation polymorphism of the 5HT2A gene (102T/C) and schizophrenia or clozapine response have yielded conflicting findings. Therefore, we investigated whether these genetic variants of the 5HT2A receptor are associated with schizophrenia or with response to clozapine treatment in a Chinese population. Ninety-seven schizophrenic patients and 101 control subjects were included in the study. The receptor variants were found at similar frequencies in schizophrenic patients and healthy control subjects. Also, we did not find the variants to influence the response to clozapine in schizophrenic patients. We suggest that the assessment method of clozapine response and the ethnicity may influence the result.

Donor site morbidity after suprafascial elevation of the radial forearm flap: a prospective study in 95 consecutive cases

From March of 1995 to November of 1997, 95 free radial forearm flaps for orofacial reconstructions were performed and included in this prospective study of donor site morbidity. All flaps were elevated using the suprafascial dissection technique. Donor site closure was performed with either split-thickness skin grafts (64 cases) or full-thickness skin grafts (31 cases). Among the 95 flaps, there were two complete flap losses and one partial flap loss because of arterial thrombosis. One orocutaneus fistula was successfully treated with a pedicled pectoralis major flap. At the donor site, the rate of complete take of skin graft was 94 percent in 95 patients. Functional and aesthetic results evaluated at least 6 months postoperatively in 50 patients revealed no significant change in grip power, pulp-to-pulp pinch power, or wrist movement in the complete skin graft take group (45 cases), whereas in the partial skin graft failure group (5 cases), both grip power and movement were significantly decreased. There was no remarkable cold intolerance in any of the 50 patients. Critical evaluations of sensory change revealed numbness distal to the donor site in 54 percent of the patients. However, dysesthesia was usually mild and improved spontaneously as time passed. Aesthetic outcome was rated as good or fair in 98 percent of the cases. The results of this prospective study show that suprafascial elevation of the radial forearm flap is superior to the classic elevation technique, particularly with regard to a higher rate of immediate complete take of skin grafts, thus avoiding impairment of range of motion and strength of the donor hand.

Down-regulation of protein kinase C: a potential mechanism for 2-amino-3-methylimidazo[4,5-f]quinoline-mediated immunosuppression

Immunosuppressive mechanism of food-born mutagenic and carcinogenic heterocyclic amine, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), was studied in murine spleen cells. IQ suppressed the IL-2 secretion and its mRNA expression. Treatment of IQ also decreased PKC activity in both the membrane fraction and the cytosol fraction. Treatment of PMA resulted in the recovery of IQ-induced suppression of IL-2 production, but the addition of ionomycin (Io) had no effect. Subsequently, we examined the effect of IQ on the activation of NF-kappaB, AP-1, and NF-AT, which are key transcription factors for IL-2 transcription. The activation of NF-kappaB and AP-1 was markedly inhibited by IQ in PMA/PHA-stimulated cells. Meanwhile, NF-AT was not affected by IQ in PMA/Io-stimulated cells. These results suggest that the immunosuppression induced by IQ might be associated with the down-regulation of PKC and subsequent blockade of the activation of NF-kappaB and AP-1 in the IL-2 gene expression.