Maintaining updated DNA-based HLA assignments in the National Marrow Donor Program Bone Marrow Registry

The National Marrow Donor Program (NMDP) has instituted an approach to address the impact of new alleles on the DNA-based HLA assignments obtained during volunteer donor typing. This approach was applied to the DRB typing results from 371,187 donors received from 14 laboratories in 1999. Samples were tested with a standardized set of sequence specific oligonucleotide reagents and the positive and negative hybridization results transmitted electronically to the NMDP. A software program interpreted the primary data into HLA assignments and rejected assignments which did not produce a result at the specified level of resolution. Comparison of the HLA assignments derived by the NMDP software to the assignments made by the laboratories using several local software prograins showed 90.5% of the assignments to be identical. Differences in assignments were explained by varying levels of typing resolution, variation in the inclusion of the second expressed DRB loci, disparity arising when alternative assignments were summarized, and failure to submit correct information. When the primary data collected in 1999 were interpreted into HLA assignments using the set of alleles defined in July 2000, 74% of the HLA-DRB assignments were altered by the description of new alleles, justifying the development of this software.

Different maternal origins of Japanese lowland and upland rice populations

Plastid subtype ID (PS-ID) sequences were determined from sequence data based on CA repeats between genes rpl16 and rpl14 in Japanese lowland and upland cultivars. The PS-ID sequences of Japanese rice cultivars showed that there are different maternal origins between lowland and upland cultivars. One subtype, 6C7A, of PS-ID sequences was predominant in all but one Japanese lowland cultivar and carried a combination of the indica-specific subtype 8C8A and japonica-specific nuclear markers for the isozyme genotype. It is probably a nuclear-cytoplasmic recombinant resulting from natural out-crossing and succeeding self-pollination. The origin of the plastid was re-confirmed by the existence of an indica-specific deletion in the plastid genome. In contrast, the Japanese upland cultivars showed two subtypes, 7C6A and 6C7A, of PS-ID sequences. An upland-specific isozyme allele as a nuclear marker was equally predominant in cultivars carrying each subtype. The existence of these particular upland-specific nuclear and cytoplasmic genotypes suggests that the origin of Japanese upland cultivars is different from that of Japanese lowland cultivars. Cultivars carrying the upland-specific nuclear genotype are common in Southeast Asia, but the combination of the upland-specific nuclear and cytoplasmic genotypes which is the same as the Japanese upland predominant type was found in cultivars only in Taiwan and Indonesia. Japanese upland cultivars are closely related to those cultivars.

[The effects of bizhongxiao decotion (BZX) on T-lymphocyte subsets in the peripheral blood of patients with rheumatoid arthritis]

OBJECTIVE

To observe the effect of BZX on T-lymphocyte subsets in the peripheral blood of patients with rheumatoid arthritis (RA) and study the mechanism of curative effects of BZX in immunization.

METHODS

42 patients with RA in active stage were divided into 1. treatment group with BZX 2. control group with western medicine and twenty healthy control group (HCG) was arranged before treatment. Their CD4+ and CD8+ were tested and the ratio of CD4+ cells to CD8+ cells was calculated before treatment and after 3 months treatment.

RESULTS

In the peripheral blood of patients with RA, CD4+ was more than that of the HCG. but CD8+ was lower and the ratio of CD4+ cell to CD8+ cells was higher than that of the HCG. After 3 months treatment, CD4+ decreased, CD8+ increased and the ratio of CD4+ cells to CD8+ cells decreased. In addition, all results were similar to the normal. We found there were no significant differences between the two treatment groups in the results after treatment.

CONCLUSION

There were cell immunoregulation disorders in patients with RA. BZX can regulate the disorder of T-lymphocyte subsets, help rebuild the immune steading and have effects of immune suppression similar to MTX combined medicine.

[The development and application of computer-aided bone histomorphometry system]

The aim of this study is to develop a Computer-aided Bone Histomorphometry System. The method is based on the Micro-graphical Digital System composed of microscope, digital camera, computer and related programs. The methodology was developed to measure the basic data on each image of visual field of hard bone tissue with computer-assistance. Following this, the parameters of bone volume, bone structure and bone metabolism were calculated based on the standardization of bone histomorphometry. Such method has been used in the experimental and clinical studies of osteoporosis to predict the fracture risk and evaluate the drug effect.

A histomorphometric and molecular study on stress adaptability of freeze-dried bone allograft

OBJECTIVE

To Investigate stress adaptability of freeze-dried bone allograft.

METHODS

Cortical and cancellous allograft were transplanted to each side of the midshaft diaphyseal ulna in two groups of 28 animals. The left transplanted allograft was free from fixation and bore a normal physiological load, while the right transplanted allograft was protected from loading by a simple external fixator and bore less load. Animals were sacrificed at the 2nd, 4th, 8th, 16th week after transplantation and specimens were taken out for bone histomorphometry studies and analysis of collagen gene expression by in situ cDNA-mRNA hybridization.

RESULTS

Labeled surface(LS) and bone mineral apposition rate(MAR) of the normally loaded graft-host bone interface were significantly higher than that of the less loaded side at the 4th, 8th, 16th week after transplantation. Parameters reflecting the internal repair process of the allograft, such as LS in cortical and cancellous bone or MAR in cortical bone of the normally loaded side were significantly higher than those of the less loaded side at the 16th week after transplantation. The result of in situ hybridization indicated that more osteoblast-like cells expressing the type I collagen gene were found in the interface or interior of normally loaded grafts.

CONCLUSION

The stimulus of physiologic load can accelerate the early union of allograft-host bone interface and later new bone creep substitution to the necrotic allograft.

Genotyping and preparation of the recombinant nucleocapsid protein antigen of hantavirus

OBJECTIVE

To identify new recombinant antigens with potential for diagnosis of hemorrhagic fever with renal syndrome (HFRS) and establish reverse transcription-polymerase chain reaction-restriction fragments length polymorphism (RT-PCR-RFLP) for genotyping of hantavirus.

METHODS

One group of primers was used to clone the full-length S genome segment and the partial S genome segment of the N-terminal. The two cloned genes were both fusionally expressed and non-fusionally expressed in the T7 system. The other group of primers was used to establish a RT-PCR method to detect RNAs in 37 virus isolates, 2 positive standard virus strains of hantavirus and 5 negative controls. The method for typing RFLP was set up by digesting the PCR products of 20 virus isolates with Ras I and Hind III.

RESULTS

The non-fusionally expressed products with a working concentration of 1:10,000 by chapping enzyme-linked immunosorbent assay (cELISA), presented good biological activity though yields were lower than that of the fusionally expressed products. The specific component of the hantavirus genome (299 bp or 577 bp) was seen in all viral samples. The genotyping of hantavirus showed that 9 out of the total were Hantann (HTN) viruses, 8 were seoul (SEO) viruses and 3 were not determined.

CONCLUSIONS

The good working titrer of expressed recombinant antigen showed that it has the potential to replace the natural antigen for detecting hantavirus antibodies. On comparison with cELISA, the detection rates for these two methods were 100% and 84.6%, and the coincidence rate was 84.6%. The former had a 15.4% higher sensitivity than the latter. The typing efficiency of RT-PCR-RFLP and sero-typing method was 85% (17/20) and 55% (11/20), respectively, showing that the former was 30% higher than the latter, while their results were highly consistent.

A prospective study of cerebral white matter abnormalities in older people with gait dysfunction

OBJECTIVES

The authors previously reported cross-sectional data suggesting a relationship between cerebral white matter hyperintensities (WMH) and gait and balance dysfunction in older people. There have been no longitudinal MRI studies to address this issue. The current study compared progression of WMH in subjects with gait and balance dysfunction with that in healthy subjects.

METHODS

Two brain MRI were performed on 70 healthy, ambulatory subjects (mean baseline age 79, range 74 to 88) with no identifiable neurologic disease. The mean time between MRI was 4 years. Gait and balance were quantified using the Tinetti Balance and Mobility Scale, and falls were documented each year. On T2-weighted MRI, total hyperintense volume (HV) within three periventricular levels was estimated using the Cavalieri principle, and WMH were graded (0 to 4) using an established semiquantitative scale.

RESULTS

Compared with those with normal gait and balance, subjects whose Tinetti scores dropped markedly (> 4 points) between first and second MRI showed a significantly greater mean increase in HV during follow-up. The larger group of subjects with an abnormal Tinetti score (< 24) at the time of second MRI showed a significantly greater mean increase in HV, compared with those with normal gait and balance at follow-up. Subjects with marked WMH at baseline showed significantly greater increase in HV over time. Subjects with abnormal Tinetti scores had significantly more falls than subjects with normal Tinetti scores.

CONCLUSIONS

Some older people develop gait and balance dysfunction that is associated with gradual onset of cerebral white matter disease.

Comparison of pulmonary arterial flow phenomena in spiral and Lecompte models by computational fluid dynamics

OBJECTIVES

The transposed great arteries are simply reversed by means of a conventional arterial switch operation with the Lecompte maneuver without resumption of their spiral relationship. We seek to clarify the functional implications of the spiral relationship of the great arteries by means of mathematic modeling.

METHODS

Computational fluid dynamics is used to compare flow phenomena of the spiral and Lecompte (nonspiral) models under various body surface areas.

RESULTS

The velocity profile and wall-shear stress distribution are more uniform for the spiral than for the Lecompte model. The pressure drop and power loss ratio are smaller for the spiral than the Lecompte model for all the body surface areas investigated. The power loss ratio increases abruptly starting from 0.43 m2 of body surface area for the Lecompte model. At that specific stage, after arterial switch operation with the Lecompte maneuver, suprapulmonary stenoses occur most frequently.

CONCLUSIONS

Reconstructing the great arteries in spiral fashion might be recommended because the blood flow patterns are more streamlined than those of the Lecompte maneuver. Initiation of stenosis might be minimized to some extent.

Exercise adds to metformin and acarbose efficacy in db/db mice

Physical exercise is frequently recommended for the treatment of type 2 diabetes, whether as primary therapy with diet modification or as an adjunct to drug therapy. We hypothesized that mild exercise would enhance the glucose-lowering effects of 2 oral antihyperglycemic drugs, metformin and acarbose, in an animal model of type 2 diabetes. Eight-week-old male C57BL/Ks (db/db) mice were sorted into control and exercise groups and dosed daily for 4 weeks with vehicle, metformin (150 mg/kg/d), or acarbose (40 mg/kg/d). Exercise consisted of swimming (initially 5 min/d and ultimately 1 h/d for the last 2 weeks). Exercise, metformin, and acarbose independently reduced serum glucose concentrations 15% to 25% compared with the respective controls (P <.0001), but the effect on glucose concentration of combining drug therapy with exercise was no greater than the sum of the individual effects. Exercise training independently increased muscle glycogen (30%; P <.05) and liver glycogen (250%; P <.05) levels and slightly reduced serum high-density lipoprotein cholesterol (-8%; P <.05), whereas drug treatment had no effect on these variables. In addition, exercise but not drug treatment prevented the approximately 30% decline in serum insulin concentrations that occurred in the control animals (P <.05). Twenty-four hours after the last drug or exercise treatment, oral glucose tolerance and hemoglobin A1c were not significantly different between groups. Treatment also did not greatly affect triglyceride, glycerol, or total cholesterol concentrations. In conclusion, exercise and drug therapy independently decreased serum glucose in db/db mice, and these effects did not appear to be synergistic. In addition, exercise training maintained serum insulin concentrations and increased tissue glycogen storage. These results suggest that exercise has the potential to add to the efficacy of oral antihyperglycemic drugs.

Effect of angiotensin II receptor antagonist and endothelin receptor antagonist on nitroglycerin tolerance in rats

OBJECTIVE

To investigate whether angiotensin II receptor antagonist and endothelin receptor antagonist can improve the nitroglycerin (Nit) tolerance in vivo.

METHODS

Twenty-four rats were divided into 4 groups (n = 6, each): Control group, Nitroglycerin (Nit) group, Nit + bosentan group and Nit + losartan group. Nitroglycerin tolerance was induced by 2-day treatment of (10 mg x kg(-1) nitroglycerin patch(0.05 mg/h). Angiotensin receptor antagonist losartan(10 mg x kg(-1) x d(-1)) and endothelin receptor antagonist bosentan (100 mg x kg(-1) x d(-1)) were given by gavage for 2 days respectively.

RESULTS

The least hypotensive response to sodium nitroprusside (SNP) was observed in Nit group. The effective percentages of hypotensive response to SNP were increased in both Nit + losartan group and Nit + bosentan group compared with Nit group [(31.95 +/- 4.45) % vs (21.00 +/- 3.69) %, P < 0.01 and (33.18 +/- 6.16) % vs (21.00 +/- 3.69) %, P < 0.01, respectively]. The maximal vessel relaxation induced by SNP was the same in 4 different groups but the highest EC50 (concentration which produces 50% of the maximal response to SNP) was found in tolerant group[(34 +/- 10) nmol/L, P < 0.01]. The ET-1 amounts in plasma and vascular tissue were markedly increased by 54% and 60% in Nit group compared with those in control group( P < 0.01). The ET-1 amounts in plasma and vascular tissue were decreased by 30% and 37% in Nit + losartan group compared with those in Nit group (P < 0.01).

CONCLUSION

Endothelin receptor antagonist and angiotensin II receptor antagonist could prevent against the Nit tolerance.

[The computer-aided measurement of medullary canal in proximal femur]

This study was conducted to search the law of the parameters of medullary canal section shape in proximal femur. The methods of image-processing and taper-curve-fit mathematics were adopted in the acquisition of data and parameters. Computer-aided method and manual method were employed to measure 10 samples of section shape in proximal femur. The results showed that no significant difference was seen between the computer-aided method and manual method(P> 0.05). This approach could reduce man-made errors and process mass samples automatically by computer.

Effects of recombinant human growth hormone (r-hGH) on experimental osteoporotic fracture healing

OBJECTIVE

To observe the effect of recombinant human growth hormone (r-hGH) on osteoporotic fracture healing in rats, and to provide an effective therapy for osteoporotic fracture.

METHODS

Thirty-six female 8-month-old SD rats were randomized into two groups: therapy group and control group. After the experimental model of osteoporotic fracture was established, the therapy group was treated with r-hGH of 2.7 mg/kg body weigh/day (1 mg=3 IU) for 10 days continuously by daily subcutaneous injection; whereas the control group was treated with equivalent saline. Plasma insulin-like growth factor I concentration was detected and bone mineral density (BMD) as well as biomechanical strength of callus were measured at 2, 4, 8 weeks.

RESULTS

Plasma insulin-like growth factor I concentration in the therapy group was higher than that in the control group (P<0.005) at 2nd week and began to decline at 4th week. At 8th week, there was no significant difference between the two groups. At 4th week, callus area and BMD in therapy group were higher than those in the control group, but at 8th week, they were lower and BMD had a significant difference between the two groups (P<0.001). Biomechanical testing of callus showed that torsional strength of the therapy group was higher than that of the control group at 4th or 8th week, meanwhile maximum torsional angle had a significant difference between the two groups (P<0.005).

CONCLUSIONS

The results show that exogenous r-hGH can stimulate osteoporotic fracture healing in rats.

Design of an interface to allow microfluidic electrophoresis chips to drink from the fire hose of the external environment

An interface design is presented that facilitates automated sample introduction into an electrokinetic microchip, without perturbing the liquids within the microfluidic device. The design utilizes an interface flow channel with a volume flow resistance that is 0.54-4.1 x 10(6) times lower than the volume flow resistance of the electrokinetic fluid manifold used for mixing, reaction, separation, and analysis. A channel, 300 microm deep, 1 mm wide and 15-20 mm long, was etched in glass substrates to create the sample introduction channel (SIC) for a manifold of electrokinetic flow channels in the range of 10-13 microm depth and 36-275 microm width. Volume flow rates of up to 1 mL/min were pumped through the SIC without perturbing the solutions within the electrokinetic channel manifold. Calculations support this observation, suggesting a leakage flow to electroosmotic flow ratio of 0.1:1% in the electrokinetic channels, arising from 66-700 microL/min pressure-driven flow rates in the SIC. Peak heights for capillary electrophoresis separations in the electrokinetic flow manifold showed no dependence on whether the SIC pump was on or off. On-chip mixing, reaction and separation of anti-ovalbumin and ovalbumin could be performed with good quantitative results, independent of the SIC pump operation. Reproducibility of injection performance, estimated from peak height variations, ranged from 1.5-4%, depending upon the device design and the sample composition.

[Effects of Nao-Yi-An granule on activity of cytochrome c oxidase in hippocampus of experimental intracerebral hemorrhagic rats]

OBJECTIVE

To explore the neuronal protective effects of a traditional Chinese medicine complex Nao-Yi-An granule(NYA) on experimental intracerebral hemorrhage(ICH) in rats.

METHODS

Eighty collagenase-induced ICH rats were used. At 12 h, 24 h, 2 d, 4 d, 7 d, cytochrome c oxidase(CO) activity was measured with histochemistry combined with gray scale scanning. Pyramidal cell(PC) counting was also employed following Nissl's staining.

RESULTS

The CO activities in NYA-treated group were less than those in model control group, and the neuronal loss was less in NYA-treated group than that in model control group.

CONCLUSIONS

The neuronal protective mechanism of NYA following ICH may be related with its maintaining activity of cytochrome c oxidase, which contributes to improving cellular aerobic metabolism and increasing energy supply for cells.

[Epidemiological survey and analysis on bronchial asthma in Guangdong Province]

OBJECTIVE

To survey asthma prevalence and risk factors of asthma in Guangdong and then to provide a basic consideration for research and preventive and therapeutic poliaes for control of asthma.

METHODS

Using uniform scheme, procedures and questionnaire, performing stratified-cluster-disproportional-random-sampling survey for the population in six areas: Santou, Shenzhen, Zhanjiang, Shaoguan, Fushan and Guangzhou; quantitative sample the prevalence rate quantitated is 1.5% (P = 0.015, q = 0.985), a sampling number stratified = 178 x 0.985/0.015 = 11,689, if the whole province were stratified into six areas, a total of 70,134 persons were supposed to be investigated, in this survey 71,867 subjects were actually examined; all the original data were inputted into soft discs in the same form of data base structure variable definition table, and then were statistically analyzed with spas 8.0 for windows on P III/450 computer, all the prevalence rates were compared by chi 2 test.

RESULTS

In this survey 676 asthmatics were found, the overall prevalence rate was 0.94%, the ratio of male to female was 1.38:1; the rate of adults was 0.99% and that of children was 0.73%, three groups with higher prevalence were children of preschool period (age < 7 years, 1.03%), young period (age 18-25 years, 1.00%) and senile period (age 66-75 years, 2.99%); the rate of city (Fushan, 1.38%) was higher than that of rural area (Zhanjiang, 0.47%); the rate of old district (1.70%) was higher than that of the new district (0.23%) in Guangzhou and the rate of historic city (Fushan, 1.38%) was higher than that of the newly developed city (Shenzhen, 0.64%); risk factors found among 676 asthmatics, persons keeping pets (cat, dog, fowl, bird) in home were reported by 46.0% (311/676), those keeping cat was 43.1% (134/311), particularly those keeping cat and both cat and dog accounted for 61.7% (192/311). Persons often exposed to side-stream smoke were reported by 54.7%. Asthmatics with allergic rhinititis were reported by 38.2%. The attack contributed to change temperature or to inhale cold air was 41.6% respectively.

CONCLUSION

This survey had basically reflected the distribution, Frequency and intensity of asthma, the overall prevalence rate was 0.94% from which it would be estimated that there could be 670,000 asthmatics in Guangdong; the relative data will provide basis for research work concerned and mass prevention and treatment of asthma.

[Clinical investigation of effects of bizhongxiao decoction (BZX) on rheumatoid arthritis on active phase]

Ninety-six patients with rheumatoid arthritis(RA) on active phase were divided into BZX-treated group(BZXG) and methotrexate-treated group(MTXG). The results showed that after 1-month treatment, symptoms and signs, such as joint tenderness, arthralgia, arthroncus, of patients in BZXG improved notably(P < 0.01 or P < 0.05), while those of patients in MTXG did not improve, there was significant difference between these two groups(P < 0.01 or P < 0.05). After 3-month treatment, these symptoms and signs improved in both groups(P < 0.01 or P < 0.05), but BZX had a better effect than MTX. ESR, CRP, RF, C3, IgG, IgA and IgM decreased significantly in both groups after treatment(P < 0.01 or P < 0.05), ESR, CRP in BZXG decreased more and faster than those in MTXG. In BZXG the obviously efficient rat was 70%, the total efficacy rate was 94%, while in MTXG was 52% and 87% respectively. It is indicated that BZX can improve symptoms and signs of patients with RA, has better and faster effects on acute phase reaction than MTX; and it has anti-immunologic effects similar to MTX, and has no obvious side effect.

[Drug resistance of acute promyelocytic leukemia (APL) to all-trans retinoic acid (ATRA) and its reversion]

OBJECTIVE

To study the mechanism of drug resistance of APL to ATRA and the methods of reversion.

METHODS

ATRA-resistant HL60 cell line and bone marrow (BM) leukemia cells from recurrent APL patients who did not respond to ATRA treatment were used in this study. Multiple drug resistance gene (mdr1) expression was determined by RT-PCR and flow cytometry. Cell proliferation and differentiation were assessed by MTT uptake and NBT reduction respectively.

RESULTS

The response of ATRA-resistant HL60 and APL cells from recurrent patients to the differentiation inducing activity of ATRA was significantly reduced, and ATRA had little effect on cell proliferation. Expression of mdr-1 was nagative in ATRA-resistant HL60 cells. It was negative in resistant APL cells even after ATRA treatment. Arsenic trioxide and homoharringtonine (HHT) could inhibit proliferation of HL60 and ATRA-resistant HL60 cells, indicating no cross-resistance with ATRA. Interferon alpha (IFN-alpha) and PGE1 could significantly inhibit proliferation of ATRA-resistant HL60 cells and restore cell differentiation induced by ATRA.

CONCLUSION

Drug resistance of APL to ATRA is not related to mdr-1. It can be reversed by IFN-alpha. There is no cross-resistance between HHT or arsenic trioxide and ATRA.

The relative frequencies of HLA-DRB1*01 alleles in the major US populations

The frequencies of alleles in the HLA-DRB1*01 family were determined in each of five US populations from a database of 82,979 individuals. Individuals typed as DR1 (or DRB1*01) comprised between 7.6%-21.3% of the individuals in each population group. Fifty-nine DR1 individuals were randomly selected from each group and subjected to high-resolution DNA typing by polymerase chain reaction using sequence-specific oligonucleotide probes. DRB1*0101 was the most common allele in the Caucasian, Asian/Pacific Islander, and Native American groups while the DRB1*0102 allele was found in the majority of African Americans and Hispanics. DRB1*0103 was present at a similar frequency in all populations. DRB1*0104, DRB1*0105, and DRB1*0106 alleles were not observed.

Electrokinetic control of fluid flow in native poly(dimethylsiloxane) capillary electrophoresis devices

Capillary zone electrophoresis (CZE) devices fabricated in poly(dimethylsiloxane) (PDMS) require continuous voltage control of all intersecting channels in the fluidic network in order to avoid catastrophic leakage at the intersections. This contrasts with the behavior of similar flow channel designs fabricated in glass substrates. When the injection plugs are shaped by voltage control and leakage from side channels is controlled by the application of pushback voltages during separation, fluorescein samples give 64 200 theoretical plates (7000 V separation voltage, E = 1340 V/cm). Native PDMS devices exhibit stable retention times (+/- 8.6% RSD) over a period of five days when filled with water. Contact angles were unchanged (+/- 1.9% RSD) over a period of 16 weeks of dry storage, in contrast to the known behavior of plasma-oxidized PDMS surfaces. Electroosmotic flow (EOF) was observed in the direction of the cathode for the buffer systems studied (phosphate, pH 3-10.5), in the presence or absence of hydrophobic ions such as tetrabutylammonium or dodecyl sulfate. Electroosmotic mobilities of 1.49 x 10(-5) and 5.84 x 10(-4) cm2/Vs were observed on average at pH 3 and 10.5, respectively, the variation strongly suggesting that silica fillers in the polymer dominate the zeta potential of the material. Hydrophobic compounds such as dodecyl sulfate and BODIPY 493/503 adsorbed strongly to the PDMS, indicating the hydrophobicity of the channel walls is clearly problematic for CZE analysis of hydrophobic analytes. A method to stack multiple channel layers in PDMS is also described.

[Effects of recombinant human growth hormone on cortical bone of ovariectomized rats]

OBJECTIVE

To study the effects of recombinant human growth hormone on cortical bone of middle femur and vertebra of variectomized rats.

METHODS

Forty 6 month-old SD rats received low or high dose of growth hormone subcutaneously 3 months after ovariectomy for 8 weeks. Bone density and biomechanical strength of the femur were measured, and the thickness of cortical bone of the middle femur and L(2) vertebra was observed. The results were compared with those in estrogen group.

RESULTS

Growth hormone increased the thickness of cortical bone and biomechanical strength and bone density. Estrogen therapy showed no effects on bone density and biomechanical strength of cortical bone.

CONCLUSION

Recombinant human growth hormone can prevent bone loss from cortical bone of ovariectomized rat.

Mitogen-activated protein kinase mediates erythropoietin-induced phosphorylation of the TAL1/SCL transcription factor in murine proerythroblasts

Ectopic expression of the basic helix-loop-helix transcription factor TAL1 (or SCL) is the most frequent gain-of-function mutation in T-cell acute lymphoblastic leukaemia. Gene-knockout studies in mice have demonstrated that TAL1 is required for embryonic and adult haematopoiesis, and considerable evidence suggests it also has important functions in terminal erythroid differentiation. We reported previously that TAL1 phosphorylation is stimulated by erythropoietin in splenic proerythroblasts isolated from mice infected with the anaemia-inducing strain of Friend virus and show here the signalling pathway responsible. Erythropoietin was found to stimulate nuclear mitogen-activated protein kinase activity in addition to TAL1 protein phosphorylation, both of which were quantitatively inhibited by the mitogen-activated protein kinase kinase inhibitor PD 098059 and the phosphatidylinositol 3-kinase inhibitor wortmannin. Tryptic phosphopeptide analysis of radiolabelled TAL1 immunoprecipitated from nuclear extracts of Friend virus-induced proerythroblasts revealed that phosphorylation of Ser(122), shown previously to be a substrate for the mitogen-activated protein kinase ERK1 (extracellular signal-regulated protein kinase) in vitro, was specifically, although not exclusively, increased by erythropoietin and inhibited by wortmannin and PD 098059. These results are consistent with an erythropoietin-stimulated signalling pathway in which there is direct activation of a mitogen-activated protein kinase kinase by phosphatidylinositol 3-kinase and identify TAL1 as one of its nuclear targets. These data suggest, in addition, a specific mechanism by which the principal regulator of erythroid differentiation could enhance TAL1 function, in addition to increasing its expression.

Molecular cloning and characterization of a mouse gene with homology to the Duffy-antigen receptor for chemokines

The Duffy antigen receptor for chemokines (DARC) is a receptor for both CXC and CC chemokines. We have cloned a mouse gene with a predicted amino acid sequence homology of approximately 63% to human DARC and localized this gene to mouse chromosome 1 between the Xmv41 and D1Mit166 loci. We further demonstrated that, like the human gene, the mouse gene exhibits a single intron of 462 bp which interrupts the open reading frame between the codons for the seventh and eighth amino acid residues. Northern blot analyses revealed that putative mDARC mRNA is highly expressed in adult mouse spleen and skeletal muscle and in whole embryos between embryonic days 8.5 to 12. Northern blot analysis of hemangiosarcomas which develop spontaneously in the spleen of the Eker rat reveal expression of mRNAs which hybridize with both DARC and CXCR2 probes, suggesting a potential role of these receptors in the angiogenesis associated with tumor formation.

Relative HLA-DRB1*13 allele frequencies and DRB3 associations of unrelated individuals from five US populations

The frequencies of 30 HLA-DRB1*13 alleles and 15 DRB3 alleles were determined for the 5 major U.S. ethnic populations: Caucasians, African Americans, Asian/Pacific Islanders, Hispanics, and Native Americans. A random sampling (163) of DRB1*13-positive individuals from each self-described ethnic group was selected out of a pool of 82,979 unrelated individuals, providing at least an 80% probability of detecting a rare allele that occurred at 1%. These 815 samples were subjected to allele-level SSOP typing and/or DNA sequencing which identified 11 different DRB1*13 alleles. DRB1*1301 and DRB1*1302 were the most common alleles seen in the five major ethnic groups while DRB1*1304 was not detected among Caucasians and DRB1*1305 was not detected among African Americans. DRB1*13 allele diversity was surprisingly more limited among African Americans compared to both Caucasians and Asian/Pacific Islanders. To determine the extent of DRB1*13-DRB3 associations, 504 of these samples expressing only one DRB3-associated DRB1 allele were subjected to PCR-SSOP typing and 14 DRB1*13-DRB3 haplotypes were detected. The distribution revealed that African Americans were significantly different from Caucasians, Asian/Pacific Islanders, and Hispanics. Allele frequency studies such as this further support previous findings that the distribution of HLA types can differ significantly among different ethnic populations.

Protection of cardiomyocytes by pinacidil during metabolic inhibition and hyperkalemia

The objective of this study is to understand the mechanism underlying the cardioprotective effects of pinacidil, an ATP-sensitive K+ channel (K(ATP)) opener. We examined the effects of 10 microM pinacidil in cultured chicken cardiomyocytes. Pinacidil caused a concentration-dependent delay in metabolic inhibition-induced increase in intracellular calcium concentration ([Ca2+]i) and creatine phosphokinase release, and this action was antagonized by glyburide, a K(ATP) blocker. Neither verapamil, an L-type Ca2+ channel blocker, nor bepridil, a Na+-Ca2+ exchange inhibitor, affected the time course of increase in [Ca2+]i induced by metabolic inhibition. Pinacidil did not have an effect on the amplitude of K+-induced increase in [Ca2+]i, but accelerated the rate of decline following peak stimulation. In contrast, glyburide reduced the amplitude of K+-induced increase in [Ca2+]i and prolonged the rate of decline. These results provide direct evidence that pinacidil protects cardiomyocytes from metabolic inhibition-induced injury by cyanide (CN) through a delay in the onset of increase in [Ca2+]i, rather than by inhibition of the L-type Ca2+-channels or by alteration of Na+-Ca2+ exchange.

[Biomechanical evaluation of five fixation techniques for the lower cervical spine]

OBJECTIVE

This study biomechanically investigated the three-dimensional motion stability of five reconstruction methods in the cervical spine, in order to provide the biomechanical basis for the clinical selection of fixation methods.

METHODS

With eight adult cervical spine fresh specimens, the three-column injury was produced at C(4 - 5) level. The spinal constructs, reconstructed by various techniques including anterior titanium locking screw plate (TLSP), posterior interspinous wiring (IW), combined fixation with the TLSP and IW (TLSP + IW), Roy-Camille plate (RP), and transpedicular screw plate (TP), were tested under six loading modes-flexion, extension, right/left lateral bending, and right/left axial rotation.

RESULTS

The three-dimensional motion stability of either TLSP or IW was less than that of intact cervical spine. The TLSP + IW and RP provided increased stability compared with the intact spine. The stabilizing capabilities of transpedicular screw plate fixation was the best in all loading modes.

CONCLUSIONS

In three-column instability of cervical spine injury, exclusive use of the anterior plate or the posterior interspinous wiring was not supported by the results. The stabilizing capabilities provided by combined anterior and posterior instrumentation and posterior plate were good. The three-column fixation for the cervical spine using transpedicular screw plate fixation offers increased stability significantly over that of other conventional cervical fixation systems.

Effects of Ca2+ channel blockers on Ca2+ loading induced by metabolic inhibition and hyperkalemia in cardiomyocytes

The effects of the L-type (nifedipine and verapamil) and the T-type (mibefradil) Ca2+ channel blockers on the increase in intracellular Ca2+ concentration ([Ca2+]i) induced by NaCN metabolic inhibition and hyperkalemia were examined in chicken cardiomyocytes using fluorescence imaging with Fura-2. NaCN induced a slow and sustained rise in [Ca2+]i, which was not affected by pretreating the cells for 5 min with nifedipine, verapamil, or mibefradil at 100 nM or 10 microM. Pretreatment of the cells with 10 microM nifedipine, verapamil, or mibefradil for 5 min remarkably inhibited the K+-induced increase in [Ca2+]i. These inhibitory effects diminished after 48-h pretreatment with nifedipine or verapamil but not with mibefradil. Ryanodine also induces an increase in [Ca2+]i, and this effect was enhanced by 48-h pretreatment of the cells with 10 microM verapamil but not with 10 microM mibefradil. We conclude that the NaCN-induced increase in [Ca2+]i is independent of the Ca2+ influx though the L-type or T-type Ca2+ channels. Chronic inhibition of the L-type Ca2+ channels but not T-type channels may enhance the ryanodine receptor-mediated Ca2+ release, which may be responsible for the development of tolerance to their inhibitory effects on K+-induced increase in [Ca2+]i.

Multisite pacing as a supplemental treatment of congestive heart failure: preliminary results of the Medtronic Inc. InSync Study

This report describes the initial results of the "InSync" study, a European and Canadian multicenter trial that examines the safety and efficacy of a multisite pacemaker (Medtronic InSync) and of left ventricular pacing leads (Medtronic 2187 and 2188) implanted via a cardiac vein as a supplemental treatment of refractory congestive heart failure. Over a 10-month period, the system was implanted successfully in 68 of the 81 (84%) patients who had been enrolled in the study. The 68 patients were, on average, 66 +/- 10 years old, had a mean left ventricular ejection fraction (LVEF) = 21% +/- 9%, and 63% were in NYHA functional Class III and 37% were in Class IV. No system implant related complication occurred. During follow-up, 7 of 10 patients who exited the study had died, 4 suddenly. There was a clinical benefit among surviving patients, which was corroborated by a significant improvement in NYHA functional class and in the Minnesota Living with Heart Failure Quality of Life Questionnaire Score (MLS) and by a longer distance covered during a 6-minute walk test. This clinical improvement was associated with a significant narrowing of the paced QRS complex during biventricular pacing, a significant decrease in the interventricular mechanical delay, and a trend towards an increase in the duration of ventricular filling. These encouraging preliminary results confirm the feasibility and reliability of this new multisite pacing system in the management of dilated cardiomyopathy and support the continuation of further evaluations of this complementary treatment of refractory congestive heart failure.

[Diagnosis and treatment of tuberculous appendicitis]

OBJECTIVE

To study the diagnosis and treatment of tuberculous appendicitis.

METHOD

12 cases (0.26%) with tuberculous appendicitis diagnosed by histopathological examination selected from 4,652 patients during 1968 to 1997 were analysed retrospectively.

RESULT

The mean age of the patients with tuberculous appendicitis was 35 years, the disease occurred 2 times more frequently in women than in men and was usually secondary to tuberculosis elsewhere in the body (7 cases). There were 7 cases with proliferative lesions, 3 cases with ulcerative lesions and 2 cases with two kinds of lesions. 12 cases were all misdiagnosed preoperatively, 2 cases were diagnosed definitely in the operation. In 12 cases, 7 cases underwent simple appendectomy, 2 cases partial celectomy and 1 case right hemicolectomy, appendectomy and resection of regional lymph nodes were performed on 2 cases, treatment of anti-TB was given postoperatively to 9 patients. All the patients recovered without complications.

CONCLUSION

It's hard to get definite diagnosis of tuberculous appendicitis before operation because of low incidence and non-specific clinical manifestations, so careful observation in the operation and routine histopathological examination must be emphasized. Early operation and postoperative treatment of anti-TB should be advocated in order to prevent from complications.

Care of elderly patients with DNR orders in Singapore--a descriptive study

OBJECTIVE

To describe the demographic profile of a cohort of elderly patients with a 'do-not-resuscitate' (DNR) order at death and to study the specific supportive measures instituted or withdrawn during the DNR period and those in force at the time of death.

METHODS

The case notes of patients who died between October 1996 and March 1997 in the Department of Geriatrics, Alexandra Hospital were studied retrospectively by a single observer.

RESULTS

Only 95 out of an eligible 102 patients' case notes could be retrieved. Seventy-two (75.8%) patients had a DNR status at death. The racial distribution was as follows: 90.3% Chinese, 5.6% Indians, 2.8% Malays and 1.4% Others while their pre-admission domicile were: own home 79.2%, nursing home 19.4% others 1.4%. Those bedbound constituted 48.6% of the cohort while 29.2% had dementia and 43.1% were totally dependent for their activities of daily living. The commonest cause of death was pneumonia while the average duration patients were on the DNR status was 5.1 days before death. The commonest measures instituted during DNR period were as follows: oxygen therapy (38.9%), nasogastric tube insertion and feeding (30.6% and 33.3% respectively), intravenous fluid administration (33.3%), blood investigations (33.3%), opioid use (33.3%) and antibiotic use (29.2%). Measures withdrawn were intravenous fluid administration (36.1%), hourly monitoring of parameters (22.2%), antibiotics (13.9%), high dependency care (12.5%) and nasogastric tube feeding (6.9%).

CONCLUSION

The DNR status is decided late in the course of a patient's illness when he may have been too ill to partake in the decision making process. Even if a DNR status was ordered, a patient might still be subjected to CPR at death.

Antibodies affecting ion channel function in acquired neuromyotonia, in seropositive and seronegative myasthenia gravis, and in antibody-mediated arthrogryposis multiplex congenita

A new autoimmune disease affecting the neuromuscular junction has been defined. Acquired neuromyotonia is associated with antibodies to voltage-gated potassium channels that act, at least in part, by reducing potassium channel function with resulting neuronal hyperactivity. This condition is quite frequently associated with thymoma and, in many cases, antibodies to acetylcholine receptors are present as well as antibodies to VGKC. Improvements in techniques and the availability of cloned DNA and recombinant forms of the AChR subunits have led to new observations concerning the specificity and roles of antibodies in myasthenia gravis. The transfection of a cell line with the epsilon subunit means that we can now accurately compare antibodies reactive with adult and fetal human AChR. This may help to determine the relationship between AChR subunit expression in different tissues and the induction of antibodies that bind specifically to the two forms, as well as to clarify the role of antibodies to fetal or adult AChR in causing ocular muscle symptoms. Serum antibodies from a few mothers with obstetric histories of recurrent arthrogryposis multiplex congenita in their babies specifically inhibit the function of fetal AChR. These observations not only explain the cause of some cases of arthrogryposis multiplex congenita, but also suggest that other fetal-specific antibodies might be responsible for other fetal or neonatal conditions. An animal model has been established to enable us to investigate the role of maternal serum factors in causing such disorders. Seronegative MG has been the subject of many studies from our laboratory over the last ten years. The transience of the effects of SNMG plasmas on AChR function strongly suggests that the plasma antibodies do not bind directly to the AChR, but inhibit function by some indirect mechanism. They do not appear to act via the cAMP-dependent protein kinase pathway, and studies are in progress to investigate the involvement of other second messenger systems.

The effect of thyrotropin receptor antibodies on the proliferation of FRTL-5 cells and the expression of protooncogene c-fos mRNA

OBJECTIVE

Hyperthyroidism and a diffuse goiter are the main symptoms of Graves' disease (GD) associated with autoantibodies to thyroid-stimulating hormone (TSH) receptor (TRAb). The present study was conducted to evaluate effects of autoantibodies in patients with GD (TRAb-IgG) on induction of the proliferation and c-fos mRNA expression in FRTL-5 cells (Fisher rat thyroid cell line).

METHODS

Highly purified IgG fractions were isolated from 11 patients with GD, TRAb-IgG and 15 normal individuals (normal controls) with Protein A Sepharose CL-4B affinity column chromatograph. FRTL-5 cells, which had been grown to subconfluency and deprived of TSH for a few days. Then, these cells were used for measuring cAMP content, 3H-thymidine incorporation in cells and the expression of c-fos mRNA respectively.

RESULTS

After stimulation of TRAb-IgG, the cAMP production and 3H-thymidine incorporation in FRTL-5 cells were much higher than those from normal controls (P < 0.05 respectively). Using 32P labelled v-fos probe by the Northern Blot method, the expression of c-fos mRNA could be induced by IgGs from patients with GD.

CONCLUSIONS

These data suggest that the stimulation of TRAb-IgG followed by cAMP production and 3H-thymidine incorporation is related to the induction of c-fos mRNA and, thus, to the growth of FRTL-5 cells.

[Incorporation of cortical allograft: a biomechanical study]

OBJECTIVE

To explore the changes of biomechanical properties of cortical allograft in different mechanical environments.

METHOD

Cortical allograft was transplanted to each side of the midshaft diaphyseal ulnar of 40 rabbits. The left transplanted allograft underwent normal physiological load, while the right underwent lower load. Animals were killed and specimens taken for examination of bone mineral density, bone porosity and maximal three-point-bend breaking load.

RESULT

The union strength of allograft-host bone junction increased constantly, while the internal creeping substitution led to an initial greater weakening of the cortical allograft itself and the later recovery of its strength. In comparison, the union strength of the normally loaded graft-host surface was significantly higher than that of the lower loaded side at eight and sixteen weeks after transplantation. At the sixteenth week, there was greater bone strength in normally loaded graft than that in less loaded graft.

CONCLUSION

The internal repair would lead to initial greater weakening of cortical allograft and the later gradual recovery of its strength. The effect of physiological load can accelerate the improvement of the biomechanical properties of allograft.

Imprinting at the mouse Ins2 locus: evidence for cis- and trans-allelic interactions

The mouse gene encoding preproinsulin 2 (Ins2) is located on the distal end of chromosome 7 in a region of several hundred kilobases that contains several imprinted genes. The exclusive expression of the Ins2 paternal allele in the visceral yolk sac during the last part of gestation indicates that Ins2 also is imprinted. However, in other tissues in which Ins2 is expressed, both alleles are active at all developmental stages. Taking advantage of two mouse strains carrying different null mutations introduced at the Ins2 locus via homologous recombination in ES cells, we examined whether genes inserted at the Ins2 locus become imprinted and have the same restricted pattern of monoallelic expression. In the first null allele, Ins2 was replaced by LacZ, under the control of the endogenous Ins2 promoter, and a Neo cassette with its own promoter was inserted 3' to LacZ (Zneo allele). In the second null allele, Ins2 and its promoter were replaced by the same Neo cassette (Neo allele). Expression of the maternally and paternally inherited genes was monitored by RT-PCR performed on various reciprocal crosses involving the two mutants and the wildtype alleles. In (Zneo x wildtype) F1 embryos, the pattern of LacZ expression was similar to that of Ins2; i.e., LacZ is expressed in the yolk sac only when paternally inherited, while its expression in the embryo proper is independent of its paternal or maternal origin. For both of the mutant alleles, Neo was transcribed only when paternally inherited, in the yolk sac as well as in the embryo. Unexpectedly, we found that LacZ transcription on the maternal chromosome varied depending on the nature of the allele on the paternal chromosome. While fully expressed in the embryo when the paternal chromosome carries the wildtype allele, the maternally inherited LacZ is extinguished when the paternal allele is the Neo allele. The major conclusion from our results is that individual genes introduced into an imprinted chromosomal domain can become imprinted, indicating the influence of long-range cis-acting effects. In addition, our data suggest that the two parental alleles may "communicate" with each other and influence the transcription at the locus.

A role for Mac-1 (CDIIb/CD18) in immune complex-stimulated neutrophil function in vivo: Mac-1 deficiency abrogates sustained Fcgamma receptor-dependent neutrophil adhesion and complement-dependent proteinuria in acute glomerulonephritis

Mac-1 (alphambeta2), a leukocyte adhesion receptor, has been shown in vitro to functionally interact with Fcgamma receptors to facilitate immune complex (IC)-stimulated polymorphonuclear neutrophil (PMN) functions. To investigate the relevance of Mac-1-FcgammaR interactions in IC-mediated injury in vivo, we induced a model of Fc-dependent anti-glomerular basement membrane (GBM) nephritis in wild-type and Mac-1-deficient mice by the intravenous injection of anti-GBM antibody. The initial glomerular PMN accumulation was equivalent in Mac-1 null and wild-type mice, but thereafter increased in wild-type and decreased in mutant mice. The absence of Mac-1 interactions with obvious ligands, intercellular adhesion molecule 1 (ICAM-1), and C3 complement, is not responsible for the decrease in neutrophil accumulation in Mac-1- deficient mice since glomerular PMN accumulation in mice deficient in these ligands was comparable to those in wild-type mice. In vitro studies showed that spreading of Mac-1-null PMNs to IC-coated dishes was equivalent to that of wild-type PMNs at 5-12 min but was markedly reduced thereafter, and was associated with an inability of mutant neutrophils to redistribute filamentous actin. This suggests that in vivo, Mac-1 is not required for the initiation of Fc-mediated PMN recruitment but that Mac-1-FcgammaR interactions are required for filamentous actin reorganization leading to sustained PMN adhesion, and this represents the first demonstration of the relevance of Mac-1-FcgammaR interactions in vivo. PMN-dependent proteinuria, maximal in wild-type mice at 8 h, was absent in Mac-1 mutant mice at all time points. Complement C3-deficient mice also had significantly decreased proteinuria compared to wild-type mice. Since Mac-1 on PMNs is the principal ligand for ic3b, an absence of Mac-1 interaction with C3 probably contributed to the abrogation of proteinuria in Mac-1-null mice.

Mechanisms of action of anti-GM1 and anti-GQ1b ganglioside antibodies in Guillain-Barré syndrome

Anti-GM1 and anti-GQ1b ganglioside antibodies are found in association with acute and chronic peripheral neuropathies, including Guillain-Barré syndrome. They are believed to arise as a result of molecular mimicry with immunogenic microbial polysaccharides. Although anti-ganglioside antibodies are suspected to play a causal role in neuropathy pathogenesis, the details of this have yet to be proven. The approach in this laboratory to solving this issue has been to generate anti-GM1 and anti-GQ1b monoclonal antibodies from peripheral blood lymphocytes of affected patients and to study their immunolocalization in peripheral nerve and their electrophysiologic effects in animal models in which peripheral nerve sites are exposed to anti-ganglioside antibodies. These data show that anti-ganglioside antibody-reactive epitopes are widely distributed in peripheral nerve and can cause electrophysiologic abnormalities in a variety of model systems; thus, these data support the view that anti-ganglioside antibody-reactive epitopes may directly contribute to neuropathy pathogenesis.

[Investigation on matrix degrading enzymes of lumbar intervertebral discs]

Changes in the macromolecular matrix of the intervertebral disc may predispose to biomechanical failure of the disc. Such changes would involve extracellular enzymes capable of altering the collagen and proteoglycan of the disc matrix. In this study, tritium-labeled type I collagen was used as a substrate to estimate the activity of collagenase in the discs of 41 cases of lumbar disc protrusion (LDP) patients by surgical intervention. The annulus fibrous (AF) and nucleus pulposus (NP) were measured separately. 34 normal discs harvested by autopsy acted as controls. For estimation of relative neutral proteinase content of 6 normal and 16 degenerated lumbar discs, polyacrylamide gelelectrophoresis (PAGE), heat-denatured collagen as a substrate, and photo-density scanning with peak area autocalculating system were adopted. The results presented that both AF and NP of the normal discs had a similar lower collagenolytic activity and a very limited activity of neutral proteinase, while the degenerated discs showed a higher activity, especially in the degenerated NP. The extruded type of LDP got a higher collagenolytic activity in NP than that of the prolapsed LDP. The fact showed that the matrix degrading enzymes play a very important role in the process of lumbar disc degeneration. The difference of disc degeneration is the biochemical basis of different clinical types of LDP. Matrix degrading enzyme system is a very complexed multienzymatic system. Other neutral proteinases may join this system besides the collagenase.

Clinical potential of microchip capillary electrophoresis systems

Clinical interest in the use of capillary electrophoresis (CE) has recently been extended to the microchip environment. Clinical analyses demand careful handling of complex samples that are often limited in quantity and in concentration. The integrated sample handling and analysis capabilities of microchip substrates thus seem ideally suited to clinical applications. This review surveys the development of sample handling (injection, mixing, and reaction) and separation elements on-chip. The integration of these elements to create a variety of clinical analyzers has been demonstrated. The application of microchip CE systems to human serum protein analysis, immunoassay, and DNA studies is reviewed, along with various other clinical applications. In addition, the clinical potential of the lab-on-a-chip concept is discussed.

Identification of four new DR52-associated DRB1 alleles: DRB1*1424, *1425, *1323 and *1324

Four previously unreported DR52-associated DRB1 alleles have been characterized through DNA sequencing, contributing to the diversity of the HLA system. DRB1*1424 is nearly identical to DRB1*1402 in the second exon, except that it contains the "I---A" motif found at codons 67-71 common to the DRB1*15 alleles. DRB1*1425 contains the "A--H" motif, found in DRB1*1401 at codons 57-60, in a sequence otherwise identical with the second exon of DRB1*1307. Compared with DRB1*11012, DRB1*1323 contains three predicted amino acid changes at codons 58 (ala-->glu), 67 (phe-->ile), and 71 (arg-->glu). The sequence of DRB1*1324 is identical to exon 2 of DRB1*1103, except that DRB1*1324 does not contain the GAG at codon 58 characteristic of the DRB1*11 alleles. These new alleles may have arisen through gene conversion, and they contribute to the complexity of the DR6 family.

[Operative treatment of displaced acetabular fractures through the ilioinguinal approach]

To reduce the incidence of ectopic ossification and improve hip joint function after the operative treatment of displaced acetabulum fractures. We surgically treated 12 acetabular fractures which involved anterior column or both anterior and posterior column fractures through the ilioinguinal approach. 10 patients were judged postoperatively to have an anatomic reduction, and 2 had a satisfactory reduction. An average of 3-year follow-up showed excellent results in 8 patients (67%) and good in 4 (33%). Radiographic results indicated excellent results in 8 (67%), patients good in 3 (25%), fair in 1 (8%). The results suggested that the ilioinguinal approach appears to diminish many of the problems associated with utilization of an extrapelvic approach, including the disturbances of the hip abductor system, heterotopic ossification, sciatic palsy, the slow recovery of hip mobility. We conclude that it is not only good for an operative treatment of anterior column fractures but also good for some of posterior column fractures.

Diversity associated with the second expressed HLA-DRB locus in the human population

Although diversity within the HLA-DRB region is predominantly focused in the DRB1 gene, the second expressed DRB loci, DRB3, DRB4, and DRB5, also exhibit variation. Within DRB1(*)15 or DRB1(*)16 haplotypes, four new variants were identified: 1) two new DRB5 alleles, DRB5*0104 and DRB5*0204, 2) a haplotype carrying a DRB1(*)15 or *16 allele without the usual accompanying DRB5 allele, and 3) a haplotype carrying a DRB5(*)0101 allele without a DRB1(*)15 or *16 allele. The evolutionary origins of these haplotypes were postulated based on their associations with the DRB6 pseudogene. Within HLA haplotypes which carry DRB3, a new DRB3(*)0205 allele and one unusual DRB3 association were identified. Finally, two new null DRB4 alleles are described: DRB4(*)0201N, which exhibits a deletion in the second exon, and a second allele, DRB4(*)null, which lacks the second exon completely. Gene conversion-like events and variation in the number of functional genes through reciprocal recombination and inactivation contribute to the diversity observed in the second expressed HLA-DRB loci.

Cytokine-induced meningitis is dramatically attenuated in mice deficient in endothelial selectins

Leukocyte accumulation in cerebrospinal fluid and disruption of the blood-brain barrier are central components of meningitis and are associated with a poor prognosis. Genetically engineered deficiencies or functional inhibition of endothelial leukocyte adhesion receptors P-, or P- plus E-selectins, lead to deficits in leukocyte rolling and extravasation. However, their impact on meningeal inflammation has not been tested previously. An acute cytokine-induced meningitis model associated with significant cerebrospinal fluid leukocyte accumulation (averaging 14,000 leukocytes/microl as early as 4 h) and blood-brain barrier permeability was developed in adult mice. This model was applied to mice deficient in P-selectin and mice doubly deficient in P- and E-selectins. Partial inhibition of cerebrospinal fluid leukocyte influx and permeability was noted in P-selectin-deficient mice. Mice doubly deficient in P- and E-selectins displayed a near complete inhibition of these parameters. Our results suggest that P- and E-selectins cooperatively contribute to meningitis and that functional blocking of both endothelial selectins in conjunction with antibiotics may provide a therapeutic approach for treatment of bacterial meningitis.

Opioid regulation of intracellular free calcium in cultured mouse dorsal root ganglion neurons

Opioid agonists induced an increase in the intracellular free calcium concentration ([Ca2+]i) or an inhibition of K+ (25 mM)-stimulated increase in [Ca2+]i in different subsets of mouse dorsal root ganglion (DRG) neurons. The total neuronal population was grouped into three classes according to somatic diameter and defined as small ( < 16 microns), intermediate (16-25 microns), or large ( > 25 microns) neurons. Substance P-like immunoreactivity was detected mainly in the small and intermediate neurons. The delta, kappa, and mu opioid receptor agonists [D-Ser2,Leu5]enkephalin-Thr (DSLET), U69593, and [D-Ala2, MePhe4, Glyol5]enkephalin (DAMGO) each induced a transient increase in [Ca2+]i in a small fraction ( < 30%) of neurons. The increases in [Ca2+]i were blocked by the opioid antagonist naloxone. The dihydropyridine-sensitive calcium channel blocker nifedipine also blocked the increase in [Ca2+]i induced by 1 microM DSLET. The rank order of potency (percentage of cells responding to each opioid agonist) was DSLET > U69593 > DAMGO. The opioid-induced increase in [Ca2+]i was observed mainly in large neurons, with a low incidence in small and intermediate neurons. Opioid agonists also caused inhibition of K(+)-stimulated increases in [Ca2+]i, which were blocked by naloxone (1 microM). Inhibition of the K(+)-stimulated increase by 1 microM DSLET or U69593 was greater in small and intermediate neurons than in large neurons.

Acute passive anti-glomerular basement membrane nephritis in P-selectin-deficient mice

P-selectin present on surfaces of activated endothelium and platelets mediates neutrophil-endothelial and neutrophilplatelet interactions. The role of P-selectin in vivo was examined in a model of acute passive anti-GBM nephritis in P-selectin-deficient and wild-type mice which was induced by intravenous injection of anti-GBM serum. There were two major differences between P-selectin-deficient and wild-type mice. Firstly, mutant mice had approximately two fold more glomerular PMNs and albuminuria than wild-type animals at the peak of neutrophil influx and proteinuria. Secondly, Lipoxin A4 (LXA4), an eicosanoid which inhibits leukocyte-endothelial adhesion in vitro, and is generated primarily by transcellular biosynthetic routes during P-selectin-mediated platelet-PMN interaction [1], was approximately 60% of wild type levels in nephritic kidneys of P-selectin-deficient mice. Injection of wild-type platelets into P-selectin-null mice restored LXA4 to wild-type levels. The corresponding PMN influx approximated PMN levels in wild-type mice receiving platelets but urine albuminuria remained higher. Although these two P-selectin-dependent events cannot be directly linked, our results point to the importance of considering both platelet and endothelial P-selectin in determining the cellular events in inflammation.