The mechanism of exercise for pain management in Parkinson's disease

The research and clinical applications of exercise therapy to the treatment of Parkinson's disease (PD) are increasing. Pain is among the important symptoms affecting the daily motor function and quality of life of PD patients. This paper reviewed the progress of research on different exercise therapies for the management of pain caused by PD and described the role and mechanism of exercise therapy for pain relief. Aerobic exercise, strength exercise, and mind-body exercise play an effective role in pain management in PD patients. The pain suffered by PD patients is divided into central neuropathic, peripheral neuropathic, and nociceptive pain. Different types of pain may coexist with different mechanistic backgrounds and treatments. The analgesic mechanisms of exercise intervention in PD-induced pain include altered cortical excitability and synaptic plasticity, the attenuation of neuronal apoptosis, and dopaminergic and non-dopaminergic analgesic pathways, as well as the inhibition of oxidative stress. Current studies related to exercise interventions for PD-induced pain suffer from small sample sizes and inadequate research of analgesic mechanisms. The neurophysiological effects of exercise, such as neuroplasticity, attenuation of neuronal apoptosis, and dopaminergic analgesic pathway provide a sound biological mechanism for using exercise in pain management. However, large, well-designed randomized controlled trials with improved methods and reporting are needed to evaluate the long-term efficacy and cost-effectiveness of exercise therapy for PD pain.

[Predictive value of left ventricular ejection fraction for the occurrence of postoperative myocardial infarction after coronary endarterectomy in patients with diffuse coronary artery disease]

Objective: To investigate the predictive value of ejection fraction for the postoperative myocardial infarction after coronary endarterectomy (CE) in patients with diffuse coronary artery disease (DCAD). Methods: Patients who underwent cardiac artery bypass graft (CABG) surgery and CE in Beijing Anzhen Hospital affiliated to Capital Medical University from May 2018 to December 2020 were enrolled in this prospective observational study. Baseline features including age, sex and echocardiography parameters were obtained. Left ventricular ejection fraction(EF) was measured by echocardiography. The patients were divided into postoperative myocardial infarction (PMI) group and non-PMI group according to PMI occurrence. Linear regression analysis, logistic regression model, and receiver operating characteristic(ROC) curve were used to analyze the correlation between left ventricular ejection fraction and PMI and the influencing factors. Results: A total of 120 patients were enrolled in the study. There were 32 patients (27%) in the PMI group (male 27(84%), age (62±8)), inferior myocardial infarction occurred in 24 (75%) patients. There were 88 patients (73%) in the non-PMI group (male 70(80%), age (62±8)). EF (55% (49%, 64%) vs. 62% (55%, 67%), P=0.01) was significantly lower in the PMI group than in the non-PMI group. Perioperative TNI, IABP use and length of hospitalization were significantly higher in the PMI group than in the non-PMI group. Multivariate logistic regression showed that lower EF was an independent risk factor of PMI (OR=0.93, 95%CI: 0.89-0.98, P=0.01) after adjusting age, sex and body mass index. ROC curve analysis showed that EF<60% could sufficiently predict the occurrence of PMI (AUC= 0.67, sensitivity 64%, specificity 69%, P=0.01). Linear regression analysis showed that left ventricular end-diastolic diameter (OR=-0.52, 95%CI:-1.13-0.60, P<0.001), graft flow in left anterior descending (OR=-0.20, 95%CI:-0.15-0.01, P=0.02) and history of diabetes (OR=-0.28, 95%CI:-8.25-1.85, P=0.002) were negatively correlated with preoperative EF value. Conclusion: Lower preoperative EF is an independent risk factor for PMI after CABG and CE in DCAD patients, closely related to the left ventricular end-diastolic diameter, graft flow in left anterior descending artery and diabetes mellitus.

[Exposure to famine in fetus and infant period and risk for hypertension in adulthood]

Objective: To investigate the relationship between exposure to famine in fetus and infant period and the risks for hypertension in adulthood. Methods: A total of 5 960 participants born between 1956 and 1965 were included in the study and were divided into unexposed group (1963-1965), fetal exposed group (1959-1961), early- childhood exposed group (1956-1958) and transitional group (1962). Logistic regression model was used to explore the association between famine exposure in early life and the risk for hypertension in adulthood. Results: Both the fetal exposure and the early-childhood exposure were the risk factors for hypertension in adulthood (OR=1.249, 95%CI: 1.049-1.486 and OR=1.360, 95%CI: 1.102-1.679). Meanwhile, in rural area, compared with unexposed group, the fetal exposure (OR=1.401, 95%CI: 1.091-1.798) and the early-childhood exposure (OR=1.460, 95%CI: 1.145-1.862) were also associated with a greater risk of hypertension in adulthood. In addition, fetal exposure and early-childhood exposure to famine in women were associated with 36.0% and 31.9% increased risks for hypertension (95%CI: 7.8%-71.7% and 95%CI: 4.8%-66.0%) according to the stratified analysis. Conclusion: Fetal exposure to famine might increase the risk for hypertension in adulthood.

[Clinical characteristics of LC-BPPV patients with bilateral direction-fixed horizontal nystagmus in primary Roll test]

Objective:To investigate the clinical features of LC-BPPV with direction-fixed horizontal nystagmus in the primary Roll test. Method:Nine patients of LC-BPPV with bilateral direction-fixed horizontal nystagmus in the first Roll test were treated by repositioning maneuvers after judging the affected side and the prognosis was observed. Result:The affected side of eight patients was the side of the apogeotropic nystagmus. Barbecue or Gufoni maneuvers was effective for reposition. The other one had no conversion of nystagmus and could not judge the affected side. Conclusion:The nystagmus performance of patients with LC-BPPV is complicated. It is necessary to carefully analyze the nystagmus performance of each position. Combining with bow and lean test, lying down test and null plane, the position of the otolith is inferred. Comprehensive use of the Barbecue or Gufoni maneuvers, forced side lying on the affected side, mastoid sniper, shaking head method is effective to complete the reposition treatment.

[Curative effect analysis of the vestibular rehabilitation training on residual dizziness after successful canalith repositioning maneuvers in patients with benign paroxysmal positional vertigo]

Objective:To explore the curative effect and quality life of the vestibular rehabilitation training on residual dizziness after successful canalith repositioning maneuvers in patients with benign paroxysmal positional vertigo (BPPV). Method:Residual dizziness after successful canalith repositioning maneuvers in patients with BPPV were enrolled in our study. They were randomized into three groups, the control group A were no disposition which include 32 patients, the intervention group B were guided to self rehabilitation training which include 33 patients, the control group C were guided to Brandt Daroff training which include 33 patients. Dizziness handicap inventory (DHI) and residual dizziness duration were used to evaluation the patients. Result:After one week vestibular rehabilitation training, the scores of DHI in group B and C decreased, and there was no significant difference (P>0.05), there were significant differences between group B and group C in group A, respectively (P<0.01). After four weeks of vestibular rehabilitation training, the scores of DHI in group B and group C were lower than those in group A, the decrease of group B was significantly higher than that of group C (P<0.01). The residual dizziness duration indicated that no statistical differences in the B, C groups (P>0.05) and scores of group B,C were significantly lower than group A (P<0.05). Conclusion:The appropriate vestibular rehabilitation training on residual dizziness after successful canalith repositioning maneuvers in patients with BPPV can help promote the central vestibular compensation, reduce the residual symptoms, improve the quality life of patients, and which can be used as the adjuvant treatment on BPPV patient who has residual dizziness symptoms.

Post-targeting strategy for ready-to-use targeted nanodelivery post cargo loading

Based on boronate formation, this study reports a post-targeting methodology capable of readily installing versatile targeting modules onto a cargo-loaded nanoplatform in aqueous mediums. This permits the targeted nanodelivery of broad-spectrum therapeutics (drug/gene) in a ready-to-use manner while overcoming the PEGylation-dilemma that frequently occurs in conventional targeting approaches.

[Research progress of intervention strategies on voice disorders in children with vocal nodules]

Vocal nodules in children is one of the common diseases in children, characterized as the hoarse voice of the children, which is mainly due to improper use of sound long-term or excessive use of the voice. The hoarseness of children's voice undermine not only the physical and mental health of children, but also the quality of life of children and their families. In recent years, the incidence of vocal nodules in children has been increasing. There are considerable differences between the children's own characteristics and adults such as bronchial lumen and cognitive and cooperate aspects, which lead to a large number of difficulties for clinical diagnosis and intervention. Based on a large number of literatures, this paper reviews the risk factors, diagnosis, voice assessment and intervention strategies of vocal nodules in children, in order to provide more comprehensive reference for the medical workers.

[Review of 1 000 Hz probe tone tympanogram applying to evaluate middle ear of infants]

1 000 Hz probe tone acoustic admittance test as a efficient method used to evaluate function of middle ear in infants, has reached consensus from domestic and foreign scholars. But there still exsits controversy on proper use in infants of months old. Here is to make a brief introduction about physiological characteristics of middle ear in infants, 1 000 Hz tympanometry and applicable age range, hoping to providing reference for future research.

Papular acantholytic dyskeratosis of the vulva associated with familial Hailey-Hailey disease

Papular acantholytic dyskeratosis (PAD) of the vulva is a rare, chronic disorder first described in 1984. It presents in young women as white to skin-coloured smooth papules over the vulva, which are persistent but asymptomatic. Histologically, there is hyperkeratosis and focal parakeratosis with acantholytic and dyskeratotic cells forming corps ronds and grains, placing PAD within Ackerman's spectrum of focal acantholytic dyskeratoses with Hailey-Hailey disease (HHD) and Darier disease. There have been 17 previous reports of PAD of the vulva, to our knowledge. Only one demonstrated a familial pattern, and none of the cases was associated with a family history of HHD. This is the first report of PAD and HHD in a single family, suggesting that PAD and HHD lie on a spectrum of disease and are genetically linked.

Molecular characterization and tissue-specific expression of invariant chain isoform in Muscovy Duck (Cairina moschata)

Invariant chain (Ii) isoform, through its thyroglobulin-like (Tg) domain, inhibits cysteine proteases during antigen presentation in vertebrates. In birds, the Ii of Muscovy Duck (MDIi) has 2 forms: MDIi-1 and MDIi-2 (MDIi isoform). To understand the genetic information and expression characteristics of MDIi-2, polymerase chain reaction, and bioinformatic analysis were performed for MDIi-2 from healthy adult Muscovy Duck. The full-length MDIi-2 cDNA sequence was found to be 1377-base pairs, encoding a 285-amino acid protein. MDIi-2 contains 63 amino acids with an insertion sequence in the Tg domain. MDIi-2 shares high identity (72.51-94.74%) with the same protein in other birds. The Tg domain of MDIi-2 is highly conserved and showed relatively high identity (96.83%) among all tested birds. The molecular structure of the Tg domain supports this conservation. MDIi-2 expression was measured in various tissues using real-time quantitative polymerase chain reaction. Similar to MDIi-1, MDIi-2 was detected in all tissues but at different levels. Higher expression level was observed in the spleen, intestinal mucosa, and bursa stipe (bursa of Fabricius stipe) than in other tissues. This suggests that MDIi-2, like MDIi-1, plays an essential role in all tissues and that its differential expression may be related to its functions in these tissues. The coexistence of 2 MDIi isoforms indicates that their functions are correlated in Muscovy Duck. This study improves the understanding of poultry immunology and may be used to improve measures to protect Muscovy Duck from disease.

Intracellular localization and association of MHC class I with porcine invariant chain

The objective was to investigate the intracellular localization and association of pig major histocompatibility complex (MHC) class I subunits with invariant chain (Ii). Pig MHC class I subunit cDNAs were cloned by RT-PCR and eukaryotic expression plasmids of α and β2m were constructed with fusions to red or enhanced green fluorescent protein (pDsRed2-N1-α, pEGFP-N1-α, pDsRed2-N1-β2m, and pEGFP-N1-β2m). A pig Ii mutant with a deleted CLIP region (DCLIP-Ii) was constructed by overlap extension PCR. Wild-type Ii and mutant Ii were cloned into pEGFP-C1 (pEGFP-C1-Ii, pEGFP-C1-DCLIP-Ii). The recombinant plasmids of MHC I subunits and pEGFP-C1-Ii (pEGFP-C1-ΔCLIP-Ii) were transiently cotransfected into COS-7 cells with Lipofectamine 2000. Immunofluorescence microscopy was performed to detect expression and intracellular localization of Ii and MHC I subunits, and immunoprecipitation was used to analyze their association. Our results indicated that pig Ii associates with integrated MHC I subunits to form oligomers, but cannot associate with single MHC I subunits. Furthermore, deletion of the Ii CLIP sequence blocks association with integrated MHC I subunits. Thus, pig Ii cannot associate with a single MHC I molecule, the α or β2m chain, but Ii and the integrated MHC I molecule can form complexes that colocalize in the endomembranes of COS-7 cells. The Ii of CLIP plays a key role in assembly of Ii and MHC I.

Molecular cloning and site-directed mutagenesis of leucine-based sorting motifs of the porcine invariant chain

Invariant chain (Ii) is a transmembrane protein that associates with MHC class II molecules in the endoplasmic reticulum. The cytoplasmic tail of Ii contains two leucine residues able to direct Ii to the endocytic pathway. We obtained the pig Ii gene by RT-PCR. Mutated Ii was prepared via site directed mutagenesis by the PCR Megaprimer method to study the effect of the two leucines on the localization of pig Ii. These mutated fragments were ligated to the vector pmCherry-C1. The recombinant plasmids were transiently transfected into COS-7 cells with Lipofectamine(TM) 2000. Fluorescence of fusion proteins (mCherry-Ii) was observed with a fluorescent microscope. Amino acid sequence alignment showed that pig Ii has domains similar to those seen in other mammalian Ii, including the cytoplasmic, transmembrane, class II-associated Ii-derived peptide, and trimerization domains. Based on observations with the fluorescent microscope, we found that two leucine-based motifs are required for pig Ii intracellular localization, and that both motifs independently mediate this function in Ii.

The effect of site-directed mutagenesis of the ambient amino acids of leucine-based sorting motifs on the localization of chicken invariant chain

Two Leu residues and their ambient amino acid residues are known to exist in the cytosolic tail of chicken invariant chain (Ii), and these play an important role as motifs in mediating the sorting endocytic pathway. We performed 20 mutations via site-directed mutagenesis by the PCR megaprimer method to study the effect of some ambient amino residues of both Leu on the localization of chicken Ii. These mutated fragments were ligated to the vector pEGFP-C1. The recombinant plasmids were transiently transfected into COS-7 cells with Lipofectamine 2000. Furthermore, the fluorescence of located fusion proteins (green fluorescent protein-Ii) was observed with a fluorescence microscope. Our results indicated that 2 Leu-based motifs are required for chicken Ii intracellular localization, and both motifs independently mediate this function of the Ii. The other amino acid residues surrounding both Leu also influence Ii-induced endosomal vacuolation. In addition, we found that Pro19, which is near the Val17-Leu18 motif, was a key residue for chicken Ii intracellular localization. Not only is it critical for endocytic targeting to each Leu, but its unique mutation can also result in altering the function of chicken Ii.

Characterization of structure and diffusion behaviour of Ca-alginate beads prepared with external or internal calcium sources

Ca-alginate beads were prepared with either external or internal calcium sources. The structures of both beads were investigated with the aid of scanning electron microscopy (SEM) and confocal microscopy. It was shown that the beads with internal calcium source had a looser structure and bigger pore size than those with external calcium source. The attempts to interpret the difference were carried out by determining the Ca content within the beads at various times, which indicated that it was the different gelation mechanisms that caused the difference of structures of both beads. Furthermore, it was also found that the diffusion rate of haemoglobin (Hb) within the beads with an internal calcium source was faster than that of the beads with an external one, which was consistent with the observation of their structures.

Highly efficient asymmetric epoxidation of alkenes with a D(4)-symmetric chiral dichlororuthenium(IV) porphyrin catalyst

A dichlororuthenium(IV) complex of 5,10,15,20-tetrakis[(1S,4R,5R,8S)-1,2,3,4,5,6,7,8-octahydro-1,2:5,8-dimethanoanthrance-9-yl]porphyrin, [Ru(IV)(D(4)-Por)Cl(2)] (1), was prepared by heating [Ru(II)(D(4)-Por)(CO)(MeOH)] (2) in refluxing CCl(4). Complex 1 is characterized by (1)H NMR (paramagnetically shifted pyrrolic protons at delta(H) = -52.3 ppm), FAB-mass spectroscopies, and magnetic susceptibility measurement (mu(eff) = 3.1 mu(B)). The ruthenium complex exhibits remarkable catalytic activity toward enantioselective alkene epoxidation using 2,6-dichloropyridine N-oxide (Cl(2)pyNO) as terminal oxidant. The Ru(IV)-catalyzed styrene epoxidation is achieved within 2 h (versus 48 h for the 2-catalyzed reaction), and optically active styrene oxide was obtained in 69% ee and 84% yield (875 turnovers). Likewise, substituted styrenes and some conjugated cis-disubstituted alkenes (e.g., cis-beta-methylstyrene, cis-1-phenyl-3-penten-1-yne, 1,2-dihydronaphthalene, and 2,2-dimethylchromenes) are converted effectively to their organic epoxides in 50-80% ee under the Ru(IV)-catalyzed conditions, and more than 850 turnovers of epoxides have been attained. When subjecting 1 to four repetitive uses by recharging the reaction mixture with Cl(2)pyNO and styrene, styrene oxide was obtained in a total of 2190 turnovers and 69% ee. UV-vis and ESI-mass spectral analysis of the final reaction mixture revealed that a ruthenium-carbonyl species could have been formed during the catalytic reaction, leading to the apparent catalyst deactivation. We prepared a heterogeneous chiral ruthenium porphyrin catalyst by immobilizing 1 into sol-gel matrix. The heterogeneous catalyst is highly active toward asymmetric styrene epoxidation producing styrene oxide in 69% ee with up to 10,800 turnovers being achieved. The loss of activity of the Ru/sol-gel catalyst is ascribed to catalyst leaching and/or deactivation. On the basis of Hammett correlation (rho(+) = -1.62, R = 0.99) and product analysis, a dioxoruthenium(VI) porphyrin intermediate is not favored.

Cross-cultural implementation of a Chinese version of the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) in Taiwan

BACKGROUND

There are no published reports of cross-cultural equivalence and interrater reliability at the level of individual symptom items assessed by a semi-structured clinical interview employing operationalised clinician ratings.

AIMS

To assess the cross-cultural clinical equivalence and reliability of a Chinese version of the World Health Organization Schedules for Clinical Assessment in Neuropsychiatry (SCAN).

METHOD

UK-US and Taiwanese groups of psychiatrists used Chinese and English transcripts of videotape interviews of Taiwanese patients to discuss cross-cultural issues and ratings of SCAN items. Item ratings were compared quantitatively individually and pooled by SCAN section.

RESULTS

Chinese equivalents were found for all SCAN items. No between-group differences were found for most individual items, but there were differences for some scaled items. Average agreement between the two groups was 69-100%.

CONCLUSIONS

Cross-cultural implementation based on SCAN in Taiwan appears valid.

[The construction and expression of two humanized scFv-urokinase fusion genes]

By using PCR and DNA recombination, two fusion genes of humanized mouse anti-human fibrin scFv and low molecular weight single chain urokinase (Scu-PA-32K) was constructed. The difference of these two fusion genes lay in the linker between two moieties, one was (Ala)3 and another was (Gly4Ser)3. These two fusion genes were both overexpressed in E. coli with the expression level at 30%. Both expression products showed the activity of binding antigen D-Dimer and activating plasminogen after the denaturation and renaturation, but under general refolding conditions, the one with linker (Gly4Ser)3 showed better effect in the renaturation of fusion protein.

[Expression of prourokinase in different mammalian cells]

Comparison studies of recombinant prourokinase(pro-UK) in various host cells, and expression vectors were carried out. Expression levels of vectors constructed in this study in different cell lines were compared. Mammalian cells expressing pro-UK were established. The levels of pro-UK expression in recombinant Namalwa, Vero and Sp2/0 cells are 200, 12.5 and 50 IU/(10(6) cells 24 h). pro-UK purities separated by immunoaffinity chromatograph are above 90%. Immunoabsorbent assay showed the ratio of pro-UK in CHO cells is lower than that from Vero and Namalwa cells. This study provide new host cells for pro-UK production.

[Construction and expression of anticolonic cancer scFv fragment]

Anticolonic cancer scFv fragment with a VH-linker-VL structure was constructed and expressed in E. coli. SDS-PAGE analysis showed the fragment cloned in pComb3 was not expressed efficiently in JM83, while cloned in pET-22b(+) highly expressed in BL21(DE3) up to 35.5% of the total bacterial protein obtained, if the culture was incubated under 30 degrees C.

[Construction and expression of a hepatocellular carcinoma specific rodent and its humanized single-chain Fv fragments in Escherichia coli]

The aim of this research is to exploit the expression strategies for two genes encoding a rodent and its humanized version single-chain fragments(scFv) specific for hepatocellular carcinoma (HCC) and compare these two scFves in antigen binding activity. Three vectors were used to express these two genes in different routes of fusion pathway, secrete pathway and intracellular pathway. The refolded single-chain antibodies were examined by antigen capture ELISA. Results showed that inclusion bodies were produced in all of the applied vectors despite of variation of IPTG concentration and culture temperature. Cell ELISA and binding competition inhibition indicated that the humanized single-chain Fv retained the similar affinity as its rodent counterpart. These results implied that the solubility of genetic antibodies are determined primarily by its amino acids sequence; The adopted humanization strategy in previous design made little effect on the natural conformation of complementarity-determining regions(CDR) of the parent antibody. The humanized HCC specific scFv can be further evaluated and developed as therapeutics.

Characteristics of recombinant human butyrylcholinesterase

AIM

To study the biochemical-pharmacological properties of the recombinant human butyrylcholinesterase (rhBChE) and thereby to size up the potential possibility of using it as a detoxifying agent in succinylcholine intoxication.

METHODS

CHO-dhfr cells were transfected with plasmids by electroporation. BChE activity was determined colorimetrically by 5, 5'-dithiobis-(2-nitrobenzoic acid) (DTNB) method. Antigenicity was estimated by enzyme-linked immunosorbent assay and Western blot.

RESULTS

The maximal expression amounted to 25.83 ng.h-1/10(6) cells. The rhBChE was highly similar to the native human BChE (nhBChE) in terms of its catalytic property, substrate affinity, inhibitor sensitivity, reactivation, stability, and immunoreactivity with anti-nhBChE antibodies. Mice challenged with 1.5 lethal dose of succinylcholine preincubated with rhBChE survived without any symptoms of intoxication.

CONCLUSION

The rhBChE and nhBChE exhibit similar biochemical-pharmacological features. It is of potential value in practical use.

Gene amplification and high-level expression of human pro-urokinase cDNA in Chinese hamster ovary cells

Human Pro-Urokinase (Pro-UK) is expressed in CHO-DHFR- cells at high efficiency by co-transfecting the mouse dhfr gene and Pro-UK cDNA under the control of the SV40 late promoter. After gene co-amplification, the product level could reach 2-3 micrograms/10(6) cells/24 h in the presence of 5 x 10(-6) mol/L MTX, and the levels can be further raised to 3.5-4 micrograms/10(6) cells/24 h by PMA superinduction. The copy number of Pro-UK cDNA in the genomes of host cells is about 200-300 copies/cell. The Western blot analysis shows that the recombinant Pro-UK has similar molecular weight to its natural counterpart, and also the amidolytic activity of the product is determined by S-2444 assay.

Identification of residues involved in polymorphic antibody binding epitopes on HLA-DR molecules

Based on previous studies it was predicted that amino acids 4 or 25 of the DR4 beta 1 and DR7 beta 1 chains are involved in polymorphic antibody binding epitopes on DR4 or DR7 molecules. These predictions were tested by analyzing monoclonal antibody (mAb) binding to transfectants expressing mutant DR4 beta 1 or DR7 beta 1 chains with single amino acid substitutions at positions 4 or 25. Antibody binding to transfectants expressing additional DR4/7 beta 1 hybrids was also analyzed to assess further the contributions of four segments of the DR4 beta 1 or DR7 beta 1 chains: amino acids 1-20, 21-40, 41-97, and the beta 2 domain. Single amino acid substitutions at positions 4 and 25 of the DR4 beta 1 chain or DR7 beta 1 chain eliminate binding of several mAb to DR4 or DR7 molecules, documenting that these residues are involved in antibody epitopes. However, the data with the hybrid DR4/7 beta 1 chains indicate that some of these epitopes require contributions from both segments 1-20 and 21-40 of these DR beta chains, whereas other epitopes can be generated by placing the appropriate segment in the context of the other DR beta chain. In addition, the data with other mAb indicate that their epitopes are determined primarily by sequences within the 41-97 segment or in the beta 2 domain.

Diverse locations of amino acids in HLA-DR beta chains involved in polymorphic antibody binding epitopes on DR(alpha, beta 1*0101), DR(alpha, beta 1*1101), and DR(alpha,beta 3*0202) molecules

In a previous study, we used transfectants expressing hybrid HLA-DR(beta 1*0403)/DR(beta 1*0701) chains to map sequences involved in polymorphic antibody binding epitopes on DR(alpha, beta 1*0403) or DR(alpha, beta 1*0701) molecules. Amino acids 1-40 of the beta 1 domain were found to make the major contributions to most of the antibody binding epitopes studied. To begin to localize sequences that contribute to polymorphic antibody epitopes on DR(alpha,beta 1*0101), DR(alpha,beta 1*1101) and DR(alpha,beta 3*0202) molecules, we used indirect immunofluorescence and flow cytometry to assess the binding of mAb to transfectants expressing hybrid DR(beta 1*0101)/DR(beta 1*1101) or DR(beta 1*1101)/DR(beta 3*0202) chains that divide the DR beta chain into three segments: amino acids 1-40, 41-97, and the beta 2 domain. The results indicate that amino acids 41-97 of the beta 1 domain on DR(beta 1*0101), DR(beta 1*1101), or DR(beta 3*0202) are critical in most of the epitopes, including those recognized by human antibodies MP4 and MP12, and mouse mAb GS88.2, I-LR1, 21r5, and 7.3.19.1, whereas amino acids 1-40 of DR(beta 1*1101) are critical in the epitope recognized by the MCS-7 mAb, and both segments 1-40 and 41-97 of DR(beta 1*1101) are important in the epitopes recognized by the I-LR2 and UL-52 mAbs. Based on these data and comparison of DR beta allelic protein sequences, the residues that may play critical roles in these antibody binding epitopes are predicted.

DRw11 haplotypes: continuum of DRB1 diversity augmented by unique DQ/DRw52 associations

cDNA sequencing of the first domains of DRB1, DRB3, DQA1, and DQB1 alleles was used to examine the extent of diversity in American black individuals expressing several DRw11 haplotypes. In addition to previously described DRw11 alleles, DRB1*1102 and DRB1*1103, two new DRB1 alleles, DRB1*11012 and DRB1*11042, were identified which differ from previously described alleles at the nucleic acid but not at the protein level. Gene conversion-like events have likely generated the DRw11 microvariation resulting in the merging of DRw11 with the DRw13 allele family. The DRw11 alleles are associated with various DQ alleles: DQw1 (DQw5 and DQw6), DQw7, and a serologically undefined DQ allele. This undefined DQ molecule, comprised of a DQ alpha/beta combination encoded by a DQw7 alpha gene (DQA1*0301) and a DQw2 beta gene (DQB1*0201), was previously observed in some DR7 and DR9 haplotypes. DRw11 haplotype diversity is augmented by the association of one of the DRw11 alleles with the DRw52c allele in contrast to the more common DRw11, DRw52b association. The extensive diversity exhibited by the DRw11 and DRw13 family of haplotypes coupled with their high frequency in populations of African ancestry suggest that the DRw11/w13 allele family may be very old and/or that these haplotypes carry some selective advantage.

Antigen-specific T cells with monogamous or promiscuous restriction patterns are sensitive to different HLA-DR beta chain substitutions

The contributions of the amino acids at 13 polymorphic positions in the HLA-DR7 beta 1 chain to T cell recognition of two antigenic peptides of tetanus toxin (p2 and p30) were assessed using transfectants expressing mutant DR7 beta 1 chains as APC for six toxin-specific T cell clones with two different restriction patterns: monogamous (restricted by DR7 only) or promiscuous (restricted by DR7; DR1; DR2, Dw21; and DR4, Dw4). Each of the 13 substitutions significantly decreased or eliminated the ability of the DR7 molecule to present a peptide to one or more of the T cell clones, but none of the substitutions abolished recognition by all clones. Interestingly, substitutions at positions 4 and 25, which are predicted in the class II model to be located outside the peptide binding groove, decreased the ability of the DR7 molecule to present Ag to some clones but not to others. Each of the four clones specific for the p2 peptide and the two clones specific for peptide p30 had a different reactivity pattern to the panel of DR7 beta 1 mutants, indicating that the TCR of each clone has a different view of the p2/DR7 or p30/DR7 complex. These data emphasize the complexity of the interactions of multiple residues in DR7 beta 1 chains in Ag-specific T cell recognition.

Polymorphic HLA-DR7 beta 1 chain residues that are involved in T cell allorecognition

The contributions to allorecognition of polymorphic amino acids in the HLA-DR7 beta 1 chain were analyzed by using mutant DR7 beta 1 chains with single amino acid substitutions at position 4, 11, 13, 25, 30, 37, 57, 60, 67, 70, 71, 74, or 78. Transfectants expressing mutant DR7 molecules were used as stimulators for six DR7-alloreactive T cell clones. The majority of the substitutions had profound effects on the ability of the DR7 molecule to stimulate one or more T cell clones. Nine of the 13 substitutions completely abrogated recognition by at least one clone. The finding that each of the substitutions in the beta-strands in the floor of the peptide binding groove affected T cell allorecognition supports the model of allorecognition in which the complex of a self-peptide bound to a class II molecule is recognized by the TCR. Interestingly, the substitution at position 4, which is predicted to be located outside the peptide binding groove, decreased the ability of the DR7 molecule to stimulate some clones. Each of the DR7-alloreactive T cell clones had a unique reactivity pattern in response to the different mutant molecules, indicating that the TCR of each clone recognized the DR7 molecule differently. Surprisingly, many of the mutant DR7 molecules induced proliferation by one or more clones that was greater than 125% of the proliferation induced by the wild-type DR7 molecule. These data indicate that multiple polymorphic residues, predicted in the class II model to be located in both the beta-strands and alpha-helix of the DR7 beta 1 chain, contribute to allorecognition of the DR7 molecule.

Polymorphic HLA-DR7 beta 1 chain residues that are involved in T cell allorecognition

The contributions to allorecognition of polymorphic amino acids in the HLA-DR7 beta 1 chain were analyzed by using mutant DR7 beta 1 chains with single amino acid substitutions at position 4, 11, 13, 25, 30, 37, 57, 60, 67, 70, 71, 74, or 78. Transfectants expressing mutant DR7 molecules were used as stimulators for six DR7-alloreactive T cell clones. The majority of the substitutions had profound effects on the ability of the DR7 molecule to stimulate one or more T cell clones. Nine of the 13 substitutions completely abrogated recognition by at least one clone. The finding that each of the substitutions in the beta-strands in the floor of the peptide binding groove affected T cell allorecognition supports the model of allorecognition in which the complex of a self-peptide bound to a class II molecule is recognized by the TCR. Interestingly, the substitution at position 4, which is predicted to be located outside the peptide binding groove, decreased the ability of the DR7 molecule to stimulate some clones. Each of the DR7-alloreactive T cell clones had a unique reactivity pattern in response to the different mutant molecules, indicating that the TCR of each clone recognized the DR7 molecule differently. Surprisingly, many of the mutant DR7 molecules induced proliferation by one or more clones that was greater than 125% of the proliferation induced by the wild-type DR7 molecule. These data indicate that multiple polymorphic residues, predicted in the class II model to be located in both the beta-strands and alpha-helix of the DR7 beta 1 chain, contribute to allorecognition of the DR7 molecule.

Antigen-specific T cells with monogamous or promiscuous restriction patterns are sensitive to different HLA-DR beta chain substitutions

The contributions of the amino acids at 13 polymorphic positions in the HLA-DR7 beta 1 chain to T cell recognition of two antigenic peptides of tetanus toxin (p2 and p30) were assessed using transfectants expressing mutant DR7 beta 1 chains as APC for six toxin-specific T cell clones with two different restriction patterns: monogamous (restricted by DR7 only) or promiscuous (restricted by DR7; DR1; DR2, Dw21; and DR4, Dw4). Each of the 13 substitutions significantly decreased or eliminated the ability of the DR7 molecule to present a peptide to one or more of the T cell clones, but none of the substitutions abolished recognition by all clones. Interestingly, substitutions at positions 4 and 25, which are predicted in the class II model to be located outside the peptide binding groove, decreased the ability of the DR7 molecule to present Ag to some clones but not to others. Each of the four clones specific for the p2 peptide and the two clones specific for peptide p30 had a different reactivity pattern to the panel of DR7 beta 1 mutants, indicating that the TCR of each clone has a different view of the p2/DR7 or p30/DR7 complex. These data emphasize the complexity of the interactions of multiple residues in DR7 beta 1 chains in Ag-specific T cell recognition.

Single amino acid changes in DR and antigen define residues critical for peptide-MHC binding and T cell recognition

Single amino acid substitutions of Ag and MHC were used to analyze the fine structure of the influenza hemagglutinin (HA)-derived epitope (HA 307-319) recognized in the context of DR7 molecules by a T cell clone. Putative T cell (HA 308, 310, 311, 313, and 316) and DR (HA 309, 312, and 317) contact residues of the Ag were identified by the use of single amino acid-substituted analogs that were tested for their T cell-activating and DR-binding capacities. The peptide-DR7-T cell interaction was further characterized by the use of a panel of 13 site-directed DR7 mutant transfectants analyzed for their capacity to present Ag to T cells, and for their purified mutant DR7 molecules to bind HA 307-319 or its single amino acid-substituted analogs. Eight mutants lost their Ag-presenting function, whereas only one had any decrease in peptide binding. Finally, for three of the mutants it was possible to correct the deleterious effects of mutation by using a particular single amino acid-substituted analog of the peptide molecule. The observed pattern of complementation led to a model that predicts that the Ag assumes an extended conformation, with a turn, in the binding groove, such that the following residues are in close proximity: DR 86-HA 309, DR 71-HA 312, DR 30-HA 314, and 315.

Single amino acid changes in DR and antigen define residues critical for peptide-MHC binding and T cell recognition

Single amino acid substitutions of Ag and MHC were used to analyze the fine structure of the influenza hemagglutinin (HA)-derived epitope (HA 307-319) recognized in the context of DR7 molecules by a T cell clone. Putative T cell (HA 308, 310, 311, 313, and 316) and DR (HA 309, 312, and 317) contact residues of the Ag were identified by the use of single amino acid-substituted analogs that were tested for their T cell-activating and DR-binding capacities. The peptide-DR7-T cell interaction was further characterized by the use of a panel of 13 site-directed DR7 mutant transfectants analyzed for their capacity to present Ag to T cells, and for their purified mutant DR7 molecules to bind HA 307-319 or its single amino acid-substituted analogs. Eight mutants lost their Ag-presenting function, whereas only one had any decrease in peptide binding. Finally, for three of the mutants it was possible to correct the deleterious effects of mutation by using a particular single amino acid-substituted analog of the peptide molecule. The observed pattern of complementation led to a model that predicts that the Ag assumes an extended conformation, with a turn, in the binding groove, such that the following residues are in close proximity: DR 86-HA 309, DR 71-HA 312, DR 30-HA 314, and 315.

Percutaneous suction aspiration for osteomyelitis. Report of two cases

The nucleotome, a recently developed instrument for percutaneous disc excision, was used for suction aspiration in two cases of osteomyelitis of the spine. The technique obtained significant amounts of pus, serosanguinous material, and tissue, which provided adequate samples for histologic examination and culture. Both patients obtained immediate relief of pain after a significant amount of pus and infected material was removed. Appropriate antibiotics were used for subsequent control of the infections. The risk and morbidity of this technique are no greater than with conventional needle biopsy.

Identification of amino acids in HLA-DPw4b beta and -DR5 beta 1 chains that are involved in antibody binding epitopes using site-directed mutagenesis and DNA-mediated gene transfer

Based on comparisons of the amino acid sequences of the beta chains of HLA class II molecules that do or do not bind the I-LR1 monoclonal antibody, we predicted that glutamic acid 56 of I-LR1-positive DPw2, DPw3, and DPw4b beta chains and the analogous glutamic acid 58 of I-LR1-positive DR5 beta 1 chains are involved in the I-LR1 epitope. Site-directed mutagenesis of DPw4b beta and DR5 beta 1 cDNAs was used to change the codons for glutamic acid 56 in DPw4b beta and glutamic acid 58 in DR5 beta 1 to the codon for alanine found in I-LR1-negative beta chains. Transfectants expressing wild-type DPw4b beta chains or DR5 beta 1 chains bind the I-LR1 monoclonal antibody, whereas transfectants expressing the mutant DPw4b beta or DR5 beta 1 chains do not bind I-LR1. Therefore, DPw4b beta glutamic acid 56 and DR5 beta 1 glutamic acid 58 are involved in the epitope recognized by the I-LR1 monoclonal antibody. Interestingly, the DR5 beta 1 glutamic acid----alanine 58 substitution also causes the loss of binding of two DR5-specific monoclonal antibodies to DR5 beta 1 molecules. Because the sequences of amino acids 36 to 64 of the DPw4b beta chain and 38 to 66 of the DR5 beta 1 chain are identical, these data raise some interesting issues about the formation of antibody epitopes on class II molecules.

Seat belt injuries of the lumbar spine--stable or unstable?

Twenty six patients with seat belt injuries of the lumbar spine were admitted into the Spinal Cord Injury Unit of the University Hospital, University of British Columbia, in the past 10 years. Four patients with pure ligamentous injuries were primarily treated surgically. Sixteen patients were treated with closed methods with a Stryker frame followed by a body cast or brace. Significant angulation with spinal deformity occurred in 6 patients. The common factor of failure of closed treatment was the inadequate reduction of initial angulation. When the initial angulation at the fracture site was adequately reduced, closed methods were associated with satisfactory results with no serious disability seen in long term follow-up. Open reduction with fixation with compression rods or wiring and fusion invariably leads to good results. It is recommended that patients with seat belt fractures of the lumbar spine may be treated by a closed method provided good reduction is obtained initially, otherwise open reduction and posterior fusion is more preferable.

[Prevention of mercury vapor contamination resulting from scraps of silver amalgam and the remainder of mercury]

Silver amalgam is applied in large amount in clinical practice, which will result in mercury vapour contamination of the stomatological environment. It is important to dispose properly of the scraps of silver amalgam and the remaining mercury, in order to reduce mercury vapour. This experiment shows that X-ray fixer solution is apparently more effective than water in preventing the escape of mercury vapour. Furthermore, such solution is available in hospitals and the used solution can also be utilized. The proper storage of silver amalgam scraps and the remaining mercury in X-ray fixer solution is apparently more effective than water in preventing the escape of mercury vapour. Furthermore, such solution is available in hospitals and the used solution can also be utilized. The proper storage of silver amalgam scraps and the remaining mercury in X-ray fixer solution will help to reduce the level of mercury vapour contamination of the stomatological environment.

Analysis of the molecular specificities of anti-class II monoclonal antibodies by using L cell transfectants expressing HLA class II molecules

Expressible HLA class II alpha- and beta-chain cDNA were used for DNA-mediated gene transfer to produce L cell transfectants expressing single types of human class II molecules. Cloned transfectants expressing nine different class II molecules were isolated: DR alpha: DR1 beta I, DR alpha: DR4 beta I, DR alpha: DR5 beta I, DR alpha: DR5 beta III (DRw52), DR alpha: DR7 beta I, DR alpha: DR4/7 beta IV (DRw53), DQ7 alpha: DQw2 beta, DQ7 alpha: DQw3 beta, and DPw4 alpha: DPw4 beta. These class II-expressing transfectants were used to analyze by flow cytometry the molecular specificities of 20 anti-class II mAb. These analyes indicate that some mAb are more broadly reactive than was previously thought based on immunochemical studies. In contrast, the narrow molecular specificities of other anti-class II mAb were confirmed by this approach. Transfectants expressing human class II molecules should be valuable reagents for studies of B cell and T cell defined epitopes on these molecules.

Analysis of the molecular specificities of anti-class II monoclonal antibodies by using L cell transfectants expressing HLA class II molecules

Expressible HLA class II alpha- and beta-chain cDNA were used for DNA-mediated gene transfer to produce L cell transfectants expressing single types of human class II molecules. Cloned transfectants expressing nine different class II molecules were isolated: DR alpha: DR1 beta I, DR alpha: DR4 beta I, DR alpha: DR5 beta I, DR alpha: DR5 beta III (DRw52), DR alpha: DR7 beta I, DR alpha: DR4/7 beta IV (DRw53), DQ7 alpha: DQw2 beta, DQ7 alpha: DQw3 beta, and DPw4 alpha: DPw4 beta. These class II-expressing transfectants were used to analyze by flow cytometry the molecular specificities of 20 anti-class II mAb. These analyes indicate that some mAb are more broadly reactive than was previously thought based on immunochemical studies. In contrast, the narrow molecular specificities of other anti-class II mAb were confirmed by this approach. Transfectants expressing human class II molecules should be valuable reagents for studies of B cell and T cell defined epitopes on these molecules.

A newly characterized HLA-DP beta-chain allele. Evidence for DP beta heterogeneity within the DPw4 specificity

cDNA clones corresponding to the DPw4 alpha- and DPw4 beta-chains were isolated from a cDNA library prepared from a DPw4 homozygous cell line, their nucleotide sequences were determined, and the corresponding amino acid sequences were deduced. This DPw4 alpha-chain is identical to the conserved DP alpha-chains from DPw4 and DPw2 haplotypes, although the DPw4 beta-chain (referred to as DPw4b beta) differs from all reported DP beta-chain sequences. The DPw4b beta-chain differs from the reported DPw4 beta sequence (referred to as DPw4a beta) at three amino acid positions in the first domain (36, 55, and 56). The DPw4b beta-chain sequence differs from the DPw2 beta-chain sequence only at position 69 in the first domain, suggesting that the lysine at position 69 in DPw4b beta and the glutamic acid at position 69 in DPw2 beta contribute to the epitopes that define "DPw4-ness" and "DPw2-ness," respectively. In addition, the patterns of sequence identities and differences among the DPw4b beta-, DPw4a beta-, DPw2 beta-, and DPw3 beta-chains suggest that the DPw4b beta sequence arose via a gene conversion event or a point mutation. The I-LR1 mAb, which was previously found to bind only to DPw2, DPw3, and DR5 molecules, binds to an L cell transfectant expressing the DPw4 alpha:DPw4b beta molecule. The DPw4b beta sequence provides the first evidence for structural heterogeneity within the DPw4 specificity.

A newly characterized HLA-DP beta-chain allele. Evidence for DP beta heterogeneity within the DPw4 specificity

cDNA clones corresponding to the DPw4 alpha- and DPw4 beta-chains were isolated from a cDNA library prepared from a DPw4 homozygous cell line, their nucleotide sequences were determined, and the corresponding amino acid sequences were deduced. This DPw4 alpha-chain is identical to the conserved DP alpha-chains from DPw4 and DPw2 haplotypes, although the DPw4 beta-chain (referred to as DPw4b beta) differs from all reported DP beta-chain sequences. The DPw4b beta-chain differs from the reported DPw4 beta sequence (referred to as DPw4a beta) at three amino acid positions in the first domain (36, 55, and 56). The DPw4b beta-chain sequence differs from the DPw2 beta-chain sequence only at position 69 in the first domain, suggesting that the lysine at position 69 in DPw4b beta and the glutamic acid at position 69 in DPw2 beta contribute to the epitopes that define "DPw4-ness" and "DPw2-ness," respectively. In addition, the patterns of sequence identities and differences among the DPw4b beta-, DPw4a beta-, DPw2 beta-, and DPw3 beta-chains suggest that the DPw4b beta sequence arose via a gene conversion event or a point mutation. The I-LR1 mAb, which was previously found to bind only to DPw2, DPw3, and DR5 molecules, binds to an L cell transfectant expressing the DPw4 alpha:DPw4b beta molecule. The DPw4b beta sequence provides the first evidence for structural heterogeneity within the DPw4 specificity.

Comparative effects of the calcium antagonist isradipine and some other dihydropyridine derivatives on regional blood flow in anesthetized open-chest dogs

The effects of isradipine (PN 200-110), isopropyl 4-(2,1,3-benzoxadiazol-4-yl)-1,4-dihydro-5-methoxycarbonyl-2,6-dim ethyl-3- pyridinecarboxylate, on some cardiovascular parameters and regional blood flow were compared with those of other dihydropyridine derivatives in anesthetized open-chest dogs. Intravenous (i.v.) administrations of isradipine 3 and 10 micrograms/kg, nifedipine 10 micrograms/kg, nicardipine 10 micrograms/kg and nisoldipine 10 micrograms/kg, decreased aortic blood pressure and increased aortic (AoF), vertebral (VBF) and coronary blood flow (CBF), but did not affect heart rate and left ventricular end-diastolic pressure. Renal blood flow was reduced by isradipine 10 micrograms/kg and nifedipine 10 micrograms/kg, but was not influenced by isradipine 3 micrograms/kg, nicardipine 10 micrograms/kg and nisoldipine 10 micrograms/kg. Left ventricular dP/dt was increased by isradipine 3 micrograms/kg, nicardipine 10 micrograms/kg and nisoldipine 10 micrograms/kg, but remained essentially unchanged following isradipine 10 micrograms/kg and nifedipine 10 micrograms/kg. The increase in AoF, VBF and CBF lasted 5-9 min following nifedipine 10 micrograms/kg or nicardipine 10 micrograms/kg, 17-30 min following nifedipine 10 micrograms/kg or nicardipine 10 micrograms/kg, 17-30 min following nisoldipine 10 micrograms/kg, and 16-44 min following isradipine 3 micrograms/kg i.v., but persisted for at least 60 min following isradipine 10 micrograms/kg. Under the experimental conditions and at the doses used in this study, all 4 drugs reduced total peripheral resistance as well as resistance in the vertebral, coronary and renal vascular beds. The results suggest that isradipine exerts cardiovascular effects similar to other calcium antagonists of the dihydropyridine group, but possesses a longer duration of action and shows a greater specificity in reducing coronary vascular resistance than nifedipine, nicardipine and nisoldipine.

Isolated colonic tuberculosis

Two cases of isolated colonic tuberculosis are reported, and recent literature on this field is reviewed. Isolated colonic tuberculosis is defined as a tuberculosis which exists in the colon except for ileocaecum, without focus in any other organ. The morphological changes are tuberculous granulation primarily located to the submucosa layer of the colon with smooth surfaces of both mucous and serous membrane. Its clinical features are atypical, just like those on X-ray examination, and even on frozen biopsy, it may sometimes be misdiagnosed. The treatment of choice is resecting the diseased segment of colon combined with anti-tuberculosis therapy.