[Effect of oral administration of branched-chain amino acids supplementation on the mortality of patients with hepatocellular carcinoma: a meta-analysis].

Objective: To investigate the effect of oral administration of branched-chain amino acids (BCAA) supplementation on the mortality of patients with hepatocellular carcinoma (HCC) after treatment. Methods: Computer searching of PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang, and Chinese Biomedical Literature Database was conducted to search for clinical controlled trials and randomized controlled trials (RCTs) on the effect of oral administration of BCAA on the mortality of patients with HCC. The retrieval time limit was from the time of the establishment of each database to December 30, 2019. Two researchers independently screened the literature and extracted the data. Another researcher assessed the risk of bias in the included studies and then used RevMan 5.3 software for meta-analysis. Results: A total of 14 studies were included with 1 179 patients. The overall results showed that oral administration of BCAA had no significant effect on the mortality of HCC patients at 1 year after treatment (RR=0.85, 95%CI:0.68-1.06, P=0.16), while the mortalities of patients at 3 years (RR=0.73, 95%CI: 0.61-0.88, P=0.000 7) and 5 years (RR=0.57, 95%CI:0.34-0.96, P=0.03) after treatment were significantly lower than those of the control group. The subgroup analysis showed that for radiofrequency ablation (RFA) patients, there was no significant difference in 1-year mortality between the BCAA group and the control group (RR=0.96, 95%CI:0.14-6.5, P=0.97), while 3-year mortality was significantly reduced (RR=0.59, 95%CI:0.43-0.81, P=0.001); for hepatectomy patients, there was no significant differences in 1 -and 3-year mortality between the two groups (RR=0.90, 95%CI:0.44-1.88, P=0.79; RR=0.97, 95%CI:0.71-1.33, P=0.85, respectively). In addition, as for albumin levels, BCAA supplementation significantly increased albumin levels without considering the treatment of HCC (SD=0.45, 95%CI: 0.29-0.90; P=0.000 1), but had no significant effect on hepatectomy patients (SD=0, 95%CI: -0.41-0.41, P=0.99). Conclusion: BCAA supplementation might improve liver reserve function and long-term prognosis of HCC patients, which was related to the surgical method. Supplementing BCAA reduced the long-term mortality of RFA patients, but had no significant effect on hepatectomy patients.

[Clinical study of psychological changes and post traumatic stress disorder in elderly patients with hip fracture].

Objective: To explore the psychological state and affected factors of elderly patients with hip fractures. Methods: A retrospective analysis of 156 elderly hip fracture patients(>65 years) admitted to the Department of Orthopaedics, the First Affiliated Hospital of Harbin Medical University from January 2016 to August 2019 was performed. General and psychological information were collected by questionnaire.General information included age, gender, education, whether surgery, length of stay.SCL-90, a self-assessment scale, was chosen as the psychological test to analyzed the elderly hip fracture patients' psychological status during hospitalization and the norms of SCL-90 in Chinese which were established in 1986 were used as the control group. The prognostic factors were examined by univariate and multivariate analysis. Results: Somatization, interpersonal sensitivity, depression, anxiety, paranoid factor scores, and total scores of the elderly hip fracture patients were significantly higher than control group(all P=0.00).Univariate analysis and logistic regression analysis showed that non-surgery treatment and more than 10 days of hospitalization were independent prognostic factors that affected the psychological state of elderly hip fracture patients (all P=0.00). Conclusion: Elderly patients hospitalized with osteoporosis and hip fractures are prone to have negative emotional and psychological changes.The length of hospitalization and the choice of treatment can affect patients' psychological state, suggesting that effective psychological intervention is necessary.

[The influence of different thyroid stimulating hormone cut-offs to diagnose subclinical hypothyroidism during the first trimester of pregnancy].

Objective: To analyze the influence of different thyroid stimulating hormone (TSH) cut-offs to diagnose subclinical hypothyroidism (SCH) in the first trimester of gestation. Methods: A total of 896 pregnant women were enrolled in Peking University International Hospital between October 2016 and March 2018. Among them, 421 pregnant women with single fetus who were conformed to the criteria of National Academy of Clinical Biochemistry (NACB), without adverse pregnancy outcomes and obstetric complications, were selected to establish their self-sequential longitudinal reference ranges of thyroid function. Then, SCH was diagnosed in the first trimester, using different TSH cutoffs, such as the upper limit of the first trimester-specific reference range, 4.0 mU/L recommended by the 2017 Guidelines of American Thyroid Association (ATA), 5.17 mU/L (Roche reagent) recommended by 2012 Guidelines of Chinese Society of Endocrinology and Chinese Society of Perinatal Medicine, and 2.5 mU/L recommended by 2011 Guidelines of ATA, respectively. Results: The TSH reference range was 0.12-4.16 mU/L in the first trimester. Using TSH>4.16, 4.0, 5.17 and 2.5 mU/L to diagnose SCH in the first trimester, the prevalence rates were 4.35% (39/896), 5.92% (53/896), 1.56% (14/896) and 20.87% (187/896), respectively. There was no statistically significant difference between the prevalence rates of SCH using the TSH upper reference limit of 4.0 mU/L and 4.16 mU/L (P=0.134). When TSH was defined as>4.0 mU/L to diagnose SCH, the sensitivity, specificity and Youden index was 97.4%, 98.2%, and 0.956, respectively. Conclusions: The TSH upper reference limit of 4.0 mU/L recommended by 2017 Guidelines of ATA can be used as a cut-off to diagnose SCH in first trimester for the areas without trimester-specific reference ranges for TSH in China.

Lack of Fc Gamma Receptor IIIA Promotes Rather than Suppresses Humoral and Cellular Immune Responses after Mucosal or Parenteral Immunization with Antigen and Adjuvants.

The Fcγ receptor IIIA (FcγRIIIA) has traditionally been known as a positive regulator of immune responses. Consistent with this, mice deficient in FcγRIIIA are protected from various inflammation-associated pathologies including several autoimmune diseases. In contrast to this accepted dogma, we show here that mice lacking FcγRIIIA developed increased rather than reduced both humoral and cellular immune responses to mucosal (sublingual) immunization with ovalbumin (OVA) given together with the strong mucosal adjuvant cholera toxin as well as to parenteral (subcutaneous) immunization with OVA in complete Freund's adjuvant. After either route of immunization, in comparison with concomitantly immunized wild-type mice, FcγRIIIA-/- mice had increased serum anti-OVA IgG (IgG1 but not IgG2) antibody responses as well as augmented cellular responses that included memory B cells and effector T cells. The increments in immune responses in FcγRIIIA-/- mice were similar to those seen in FcγRIIB-/- mice. Furthermore, OVA-pulsed FcγRIIIA-/- DCs, similar to OVA-specific FcγRIIB-/- DCs, had enhanced capacity to activate OVA-specific OT-II T cells, which was even further pronounced when DCs were pulsed with IgG1-complexed OVA. Our data support an inhibitory-regulatory role of FcγRIIIA on vaccine/adjuvant-induced immune responses and demonstrate that lack of FcγRIIIA can promote rather than suppress both humoral and cellular immune responses.

[Differential diagnosis and surgical management in chondrosarcoma of the jugular foramen].

Objective: To explore the diagnosis, surgical management and outcome of jugular foramen chondrosarcoma (CSA). Methods: Fifteen patients with jugular foramen CSA hospitalized in the Department of Otorhinolaryngology Head and Neck Surgery of Chinese PLA General Hospital from December 2002 to February 2020 were retrospectively collected,of whom 2 were male and 13 were female, aging from 22 to 61 years old. The clinical symptoms and signs, imaging features, differential diagnosis, surgical approaches, function of facial nerve and cranial nerves IX to XII, and surgical outcomes were analyzed. Results: Patients with jugular foramen CSA mainly presented with facial paralysis, hearing loss, hoarseness, cough, tinnitus and local mass. Computed tomography (CT) and magnetic resonance (MR) could provide important information for diagnosis. CT showed irregular destruction on bone margin of the jugular foramen. MR demonstrated iso or hypointense on T1WI, hyperintense on T2WI and heterogeneous contrast-enhancement. Surgical approaches were chosen upon the sizes and scopes of the tumors. Inferior temporal fossa A approach was adopted in 12 cases, inferior temporal fossa B approach in 2 cases and mastoid combined parotid approach in 1 case. Five patients with facial nerve involved received great auricular nerve graft. The House Brackmann (H-B) grading scale was used to evaluate the facial nerve function. Preoperative facial nerve function ranked grade Ⅴ in 4 cases and grade Ⅵ in 1 case. Postoperative facial nerve function improved to grade Ⅲ in 2 cases and grade Ⅵ in 3 cases. Five patients presented with cranial nerves Ⅸ and Ⅹ palsies. Hoarseness and cough of 2 cases improved after operation, while the other 3 cases did not. All the patients were diagnosed CSA by histopathology and immunohistochemistry, with immunohistochemical staining showing vimentin and S-100 positive, but cytokeratin negative in tumor cells. All patients survived during 28 to 234 months' follow-up. Two patients suffered from tumor recurrence 7 years after surgery and received revision surgery. No complications such as cerebrospinal fluid leakage and intracranial infection occurred after operation. Conclusions: Jugular foramen CSA lacks characteristic symptoms or signs. Imaging is helpful to differential diagnosis. Surgery is the primary treatment of jugular foramen CSA. Patients with facial paralysis should receive surgery in time as to restore the facial nerve. Long-term follow-up is necessary after surgery in case of recurrence.

[Pancreatic pseudocyst after pegaspargase treatment in six children].

Objective: To investigate the clinical characteristics and treatment of pancreatic pseudocyst after pegaspargase treatment in children. Methods: The clinical data of 6 children with pancreatic pseudocyst after pegaspargase treatment in the Department of Pediatrics in Peking University Third Hospital from July 2018 to February 2021 were analyzed retrospectively. Results: There were 4 males and 2 females, and their age of onset was 9.5 (5.8, 13.0) years. The total number of pegaspargase applications was 2.5 (2.0, 3.5) times. The course from the last dose of pegaspargase to the onset of pancreatitis was 11.0 (9.0, 17.2) days, and 42.5 (35.0, 129.5) days from the onset of pancreatitis to the diagnosis of pancreatic pseudocyst. Abdominal pain was the most prominent manifestation of pancreatitis (6/6). All of the 6 children were asymptomatic when pancreatic pseudocyst was noted, and were treated conservatively at first, but one case later developed intermittent abdominal distension or nausea after eating. All the cases had pancreatic pseudocyst enlargement during the conservative treatment. Three children were treated with endoscopic ultrasound-guided transgastric drainage, and the cyst disappeared from 10 days to 4 months after the operation. The other 3 children received endoscopic retrograde cholangiopancreatography (ERCP)-guided transpapillary drainage, but one of them turned to surgery due to pancreatic duct stricture, and in the rest 2 children the cyst disappeared at 1 and 3 months after operation respectively. Regarding safety issues, 1 child who received ERCP-guided transpapillary drainage had acute postoperative pancreatitis, which were improved after treatment, and the other 5 had no complications. Conclusions: Pancreatic pseudocyst after pegaspargase chemotherapy can be asymptomatic in the early stage, and should be diagnosed with a history of pegaspargase treatment and timely imaging examination. Conservative treatment is the first choice for asymptomatic pseudocyst. When the pseudocyst enlarges, different endoscopic drainage treatments are required according to whether the pseudocyst is connected with the main pancreatic duct.

Mucosally induced immunological tolerance, regulatory T cells and the adjuvant effect by cholera toxin B subunit.

Induction of peripheral immunological tolerance by mucosal administration of selected antigens (Ags) ('oral tolerance') is an attractive, yet medically little developed, approach to prevent or treat selected autoimmune or allergic disorders. A highly effective way to maximize oral tolerance induction for immunotherapeutic purposes is to administer the relevant Ag together with, and preferably linked to the non-toxic B subunit protein of cholera toxin (CTB). Oral, nasal or sublingual administration of such Ag/CTB conjugates or gene fusion proteins have been found to induce tolerance with superior efficiency compared with administration of Ag alone, including the suppression of various autoimmune disorders and allergies in animal models. In a proof-of-concept clinical trial in patients with Behcet's disease, this was extended with highly promising results to prevent relapse of autoimmune uveitis. Tolerization by mucosal Ag/CTB administration results in a strong increase in Ag-specific regulatory CD4(+) T cells, apparently via two separate pathways: one using B cells as APCs and leading to a strong expansion of Foxp3(+) Treg cells which can both suppress and mediate apoptotic depletion of effector T cells, and one being B cell-independent and associated with development of Foxp3(-) regulatory T cells that express membrane latency-associated peptide and transforming growth factor (TGF-beta) and/or IL-10. The ability of CTB to dramatically increase mucosal Ag uptake and presentation by different APCs through binding to GM1 ganglioside (which makes most B cells effective APCs irrespective of their Ag specificity), together with CTB-mediated stimulation of TGF-beta and IL-10 production and inhibition of IL-6 formation may explain the dramatic potentiation of oral tolerance by mucosal Ags presented with CTB.

[Relationship between gene polymorphism at rs2228055 locus in the exon region of interleukin-10 receptor A and susceptibility to food allergy in children].

Objective: To investigate the relationship between gene polymorphism of rs2228055 locus in the exon region of interleukin-10 receptor A (IL-10RA) and susceptibility to food allergy in children. Methods: This was a case-control study. The food allergy group had 150 children who were diagnosed with food allergy in the Pediatric Food Allergy Clinic of Peking University Third Hospital from August 1, 2017 to November 30, 2018. Another 150 healthy children attended Child Health and Development Center in the same hospital were selected as control group. The genotypes of rs2228055 locus in both groups were detected by PCR re-sequencing. And the genotypes and allele frequencies of rs2228055 locus were compared between these two groups, as well as between food allergy children with positive and negative allergen specific IgE, and between those with and without involvement of different organs. Using the computer virtual mutation to stimulate the changes of amino acid caused by change of rs2228055 locus allele, to analyze the effect of amino acid changes on the structure of IL-10RA. The chi-square test was used for comparison between groups. Results: (1) There were 92 males and 58 females in food allergy group, and 86 males and 64 females in control group, without any statistically significant difference (χ(2)=0.497, P=0.481). The ages of the two groups were 4.2 (0.1-15.0) and 8.0 (0.1-14.0) years old, respectively, the difference was statistically significant (Z=-6.109, P<0.01). (2) The genotype frequencies of rs2228055 locus in the food allergy group and the control group were as follows: AA accounted for 73 (48.7%) and 98 (65.3%), AG accounted for 62 (41.3%) and 42 (28.0%), and GG accounted for 15 (10.0%) and 10 (6.7%), respectively. The allele frequencies in the two groups were as follows: 208 (69.3%) and 238 (79.3%) for A, 92 (30.7%) and 62 (20.7%) for G, respectively. AG and GG genotype frequency and the allele G frequency in food allergy group were significantly higher than that in control group (χ(2)=8.501 and 7.862, P=0.014 and 0.005, respectively). (3) There were no significant differences in genotype frequencies and allele frequencies of rs2228055 locus of allergen-specific IgE-positive and negative food allergy children (all P>0.05). (4) There were no significant differences in genotype frequencies and allele frequencies of rs2228055 locus in the manifestations of skin, digestive system and respiratory system in food allergy children (all P>0.05). (5) The computer virtual mutation showed that the mutation energy was -0.08 without any increase in the stability of IL-10RA when the amino acid encoded by rs2228055 locus was changed from isoleucine to valine. Conclusions: The frequencies of genotype AG, GG and allele G of rs2228055 locus in the IL-10RA exon region in food allergy children are higher than that in non-allergic children, and those with the G allele are more likely to develop food allergy.

Lycopene protects myocardial ischemia injury through anti-apoptosis and anti-oxidative stress.

OBJECTIVE: The aim of this research was to explore the protective effect of lycopene (Lyc) on myocardial ischemia injury through anti-apoptosis and anti-oxidative stress. MATERIALS AND METHODS: 75 rats were divided into 5 groups: sham operation group (control group), model group, low-dose group (Lyc+2 mg/kg), medium-dose group (Lyc+4 mg/kg) and high-dose group (Lyc+6 mg/kg). The rat model of myocardial ischemia was established by a subcutaneous injection of isoproterenol (85 mg/kg) for two consecutive days. Conventional HE staining and Masson staining were performed for pathological changes. Biochemical indicators were measured by the enzyme-linked immuno sorbent assay (ELISA). Western blotting was used to measure the levels of related proteins in JNK/STAT signaling pathway. RESULTS: Compared to control group, the levels of CK-MB, TC, and TGs were significantly increased in model group. The levels of CK-MB, TC, and TGs in each Lyc-administered group were decreased. After Lyc was administered, the SOD, CAT, GSH-Px activities and MDA content were all restored. The serum levels of IL-1ß, TNF-α and IL-6 in control group were significantly lower than in model group. When the Lyc was administered, the serum IL-1ß, TNF-α and IL-6 levels in medium-dose group and high-dose group were significantly decreased. The levels of Bax/Bcl-2, Cyt-c, and Caspase-3 in model group were significantly higher than control group. Changes of Bax/Bcl-2, Cyt-c, and Caspase-3 in medium-dose and high-dose groups after the administration of Lyc were restored significantly. The levels of p-JNK/JNK, p-STAT1 (Tyr701)/STAT1, p-STAT1 (Ser727)/STAT1, p-STAT3 (Tyr705)/STAT3 were significantly increased, while p-STAT3 (Ser727)/STAT3 was significantly decreased. When Lyc was administered, the expression levels of p-JAK/JAK, p-STAT1 (Tyr701)/STAT1, p-STAT1 (Ser727)/STAT1, p-STAT3 (Tyr705)/STAT3 protein in medium-dose group and high-dose group were significantly decreased, and the expression level of p-STAT3 (Ser727)/STAT3 protein was significantly increased. CONCLUSIONS: Lyc could show a protective effect on oxidative stress injury and anti-cardiomyocyte apoptosis of myocardial ischemia, and its possible mechanism was to attenuate the activation of JNK/ERK signaling pathway induced by myocardial injury.

The effect of C-type natriuretic peptide on delayed rectifier potassium currents in gastric antral circular myocytes of the guinea-pig.

C-type natriuretic peptides (CNP) play an inhibitory role in smooth muscle motility of the gastrointestinal tract, but the effect of CNP on delayed rectifier potassium currents is still unclear. This study was designed to investigate the effect of CNP on delayed rectifier potassium currents and its mechanism by using conventional whole-cell patch-clamp technique in guinea-pig gastric myocytes isolated by collagenase. CNP significantly inhibited delayed rectifier potassium currents [I(K (V))] in dose-dependent manner, and CNP inhibited the peak current elicited by depolarized step pulse to 86.1+/-1.6 % (n=7, P<0.05), 78.4+/-2.6 % (n=10, P<0.01) and 67.7+/-2.3 % (n=14, P<0.01), at concentrations of 0.01 micromol/l, 0.1 micromol/l and 1 micromol/l, respectively, at +60 mV. When the cells were preincubated with 0.1 micromol/l LY83583, a guanylate cyclase inhibitor, the 1 ?micromol/l CNP-induced inhibition of I(K (V)) was significantly impaired but when the cells were preincubated with 0.1 micromol/l zaprinast, a cGMP-sensitive phosphodiesterase inhibitor, the 0.01 micromol/l CNP-induced inhibition of I(K (V)) was significantly potentiated. 8-Br-cGMP, a membrane permeable cGMP analogue mimicked inhibitory effect of CNP on I(K (V)). CNP-induced inhibition of I(K (V)) was completely blocked by KT5823, an inhibitor of cGMP-dependent protein kinase (PKG). The results suggest that CNP inhibits the delayed rectifier potassium currents via cGMP-PKG signal pathway in the gastric antral circular myocytes of the guinea-pig.

Sensitive electrochemical enzyme immunoassay microdevice based on architecture of dual ring electrodes with a sensing cavity chamber.

A novel electrochemical detection architecture was investigated for enzyme immunoassay sensors. Microchips with dual-ring working and counter electrodes, and a sensing cavity chamber were made on glass slides. The glass surface of the microchip was coated by 3-aminopropyltriethoxysilane (APTES). Goat IgG, as a example, was covalently captured on APTES-modified glass surfaces through glutaraldehyde (GA) as a cross-linker. Enzyme substrate, p-aminophenyl phosphate (PAPP) was prepared by electrolysis. The enzyme conversion from home-synthetic PAPP to p-aminophenol (PAP) was examined by differential pulse voltammetry (DPV). A competitive inhibition enzyme-linked immunosorbant assay (ELISA) was designed to test the system. Experimental results demonstrate that a detection limit of 118 fg/ml of goat IgG and a dynamic range of 118 fg/ml to 1.18 ng/ml, up to five orders of magnitude could be achieved. Due to its novel architecture design and electronic detection scheme, the method can be used to fabricate portable electrochemical ELISA lab-on-chip systems. The technology could have great potential in clinical diagnostic applications.

Inhibitory effect of C-type natriuretic peptide on L-type calcium channel currents in gastric antral myocytes of guinea pigs.

The role of C-type natriuretic peptide (CNP) in the gastrointestinal tract is still unclear. This study was designed to investigate the effect of CNP on barium current (I(Ba)) through the L-type calcium channel in gastric antral myocytes of guinea pigs. The whole-cell patch clamp technique was performed in gastric antral myocytes isolated by collagenase in guinea pigs. CNP significantly inhibited I(Ba) in a dose-dependent manner at the concentrations of 0.001, 0.01, and 0.1 micromol/l, CNP inhibited I(Ba) to 81.56 +/- 2.48 %, 73.64 +/- 3.65 %, and 57.77 +/- 4.93 % of control at 0 mV, respectively. The values of steady-state half-inactivation voltage (33.6 +/- 2.6 mV and 33.8 +/- 3.4 mV, in control and CNP groups, respectively) or the half-activation voltage (-12.6 +/- 2.2 mV and 12.4 +/- 1.8 mV) of I(Ba) were not significantly changed (p > 0.05, n = 6). 8-br-cGMP (1 mmol/l) mimicked the effect of CNP on I(Ba), and the peak current of I(Ba) was inhibited from -403.84 +/- 61.87 pA to 318.94 +/- 67.17 pA (p < 0.05, n = 5). In the presence of LY83583 (0.1 micromol/l), a nonspecific inhibitor of guanylate cyclase, CNP (0.1 micromol/l)-induced inhibition of I(Ba) was partially blocked (n = 13, p < 0.05 ). However, when the cell was pretreated with zaprinast (0.1 micromol/l), an inhibitor of cyclic guanosine monophosphate (cGMP) sensitive phosphoesterase, the inhibitory effect of CNP on I(Ba) was significantly potentiated (n = 11, p < 0.05). KT5823 (1 micromol/l), a cGMP-dependent protein kinase (PKG) inhibitor, almost completely blocked CNP-induced inhibition of I(Ba). The results suggested that CNP can inhibit L-type calcium channel currents, and the inhibitory effect is mediated by pGC-cGMP-PKG-dependent signal pathway in gastric antral myocytes of guinea pigs.

Autoreactive T and B cells in nervous system diseases.

BACKGROUND: Abnormal autoimmunity could play a role in the pathogenesis of multiple sclerosis (MS), in analogy with its model experimental allergic encephalomyelitis (EAE) which can be transferred by T cell lines directed to myelin basic protein (MBP) and myelin proteolipid protein (PLP), and worsened with antibody to myelin oligodendrocyte glycoprotein (MOG). Whether T and B cell reactivities to these autoantigens, and to myelin-associated glycoprotein (MAG) which is another possible target for autoimmune attack, occur in MS and then especially in the cerebrospinal fluid (CSF) with its close relation to the nervous tissue, is not clear. Myasthenia gravis, a prototype for autoimmune disease in humans, is characterized by IgG antibodies to acetylcholine receptor (AChR) in serum, but it is not known whether an augmented T cell response to AChR occurs in this disease. Nerve trauma has been speculated upon to be associated with exacerbations of MS; if nerve trauma recruits augmented autoimmune T and B cell responses is not known. High numbers of anti-myelin protein and anti-AChR antibody secreting cells have been described in cord blood, but whether corresponding T cell reactivities occur remains to be settled. METHODS: Antigen specific T cell responses in blood and CSF are studied regarding specificity, quantity and functional differentiation by counting numbers of cells which, upon antigen stimulation, respond by secretion of interferon-gamma (IFN-gamma). Similarly, the B cell responses to autoantigens are evaluated by counting cells which, in presence of antigen, secrete specific antibodies of IgG, IgA and IgM isotypes. RESULTS: MS is characterized by elevated numbers of T cells recognizing MBP, PLP, MAG and MOG as well as the synthetic MBP amino acid sequences 1-20, 63-88, 89-101, 96-118, 110-128 and 148-165, without immunodominance for any of these components. PLP, MOG and MAG reactive T cells are strongly enriched in the patients' CSF, as previously also shown for MBP reactive T cells. Similarly, elevated numbers of B cells with these specificities and enriched in CSF were found in MS. No preferential autoimmune T cell response was apparent after subdivision of the MS patients according to their HLA-DR genotype. A majority of patients with myasthenia gravis had AChR and alpha-subunit reactive T cells in peripheral blood, and also anti-AChR antibody secreting cells of the IgG, less frequently IgA and IgM isotypes. Peripheral nerve trauma in form of diagnostic sural nerve biopsy is accompanied by transient elevation in blood of T cells recognizing MBP and MAG which are common to the central and peripheral nervous system, and to the peripheral nerve myelin proteins P0 and P2. Myelin protein and AChR reactive T and B cells occur also in patients with other neurological diseases and tension headache, and in healthy subjects, but less frequently and at lower numbers than in MS and myasthenia gravis, respectively. Cord blood contains higher numbers of myelin protein and AChR reactive T cells in comparison with blood from healthy adults. CONCLUSION: Antigen-specific T cells recognizing multiple myelin proteins and MBP peptides constitute a regular finding in MS. These autoimmune T cells are strongly enriched in CSF. In myasthenia gravis, increased levels of AChR and alpha-subunit reactive T cells as well as anti-AChR IgG, less frequently IgA and IgM antibody secreting cells can be demonstrated in most patients. T and B cells with the mentioned specificities can also be identified in patients with tension headache and healthy subjects but less frequently and at lower numbers, and they are assumed to reflect normally occurring autoimmune T and B cell repertoires. These are augmented after nerve trauma and in the newborn...

Conjugal multiple sclerosis: immunogenetic characterization and analysis of T- and B-cell reactivity to myelin proteins.

We describe two families with conjugal multiple sclerosis. Onset of symptoms in the husbands occurred 11 and 17 years after onset of relapsing/remitting symptoms in their wives. There were no similarities regarding clinical manifestations of MS within each family. Evaluation of T-cell repertoire by enumeration of cells secreting interferon-gamma in response to proteolipid protein (PLP), myelin basic protein (MBP), and to various synthetic MBP peptides revealed similar patterns of T-cell reactivity within the families both in MS-affected parents and unaffected children. Genomic HLA-DR-DQ typing showed that T-cell reactivity was independent of HLA class II phenotype. Analysis of B-cell responses in blood showed low numbers of cells secreting IgG, IgA, or IgM antibodies against MBP, PLP, myelin-associated glycoprotein, and myelin-oligodendrocyte glycoprotein both in MS-affected and unaffected family members. In conclusion, our study of two families with conjugal MS has shown a dominant T-cell response against the same MBP peptide within the family both in MS-affected parents and unaffected children, and this T-cell response seems to be independent of the HLA class II phenotypes of the family members.

Virus-reactive and autoreactive T cells are accumulated in cerebrospinal fluid in multiple sclerosis.

Elevated numbers of B cells--plasma cells secreting antibodies to measles and mumps virus, and to myelin associated glycoprotein (MAG), one of several putative myelin autoantigens--have previously been reported in cerebrospinal fluid (CSF) from patients with multiple sclerosis (MS), while it is unknown if corresponding T cell reactivities occur. We have defined the T cell reactivities to measles and mumps virus and to MAG in an immunospot assay which is based on the detection of secretion of interferon-gamma (IFN-gamma) by single cells upon stimulation with specific antigen in short term cultures. Patients with MS had higher numbers of MAG-reactive T cells in blood compared to controls, while no differences were observed for measles or mumps virus-reactive T cells. In CSF, elevated numbers of MAG-reactive T cells and also of measles- and mumps-reactive T cells were found in patients with MS compared to other neurological diseases. A strong accumulation of antigen-reactive T cells was observed in the MS patients' CSF compared to blood. The magnitude of these T cell reactivities did not correlate with clinical MS variables. The T cell repertoire in MS thus includes, besides myelin basic protein, proteolipid protein and myelin oligodendrocyte glycoprotein, also MAG and, in addition, measles and mumps virus. It is not clear whether these T cell reactivities accumulated in the CSF have importance for the pathogenesis of MS or reflect phenomena secondary to myelin damage, or result from both these alternatives.

Autoreactive T and B cell responses to myelin antigens after diagnostic sural nerve biopsy.

To study whether nervous tissue trauma provokes myelin antigen autoreactive T and B cell responses in humans we examined consecutive blood samples from 7 patients with polyneuropathy undergoing diagnostic sural nerve biopsy and 8 control patients undergoing other types of minor surgery. The antigen-specific T cells were assessed by enumerating cells secreting interferon-gamma (IFN-gamma) in response to the myelin components P0, P2, myelin basic protein (MBP) and myelin associated glycoprotein (MAG), and to 4 selected MBP peptides. B cell mediated immunity was assessed by counting numbers of cells secreting antibodies directed against the myelin proteins. On day 7 after biopsy, there were 3-10-fold increased numbers of T and B cells reactive with P0, P2, MBP and MAG in blood of polyneuropathy patients compared to controls, while levels of cells recognizing purified protein derivate or responding to phytohemagglutinin (PHA) did not differ significantly. Comparison of prebiopsy levels on day 0 with post-biopsy levels on day 7 in the polyneuropathy patients revealed a significant increase in T cells recognizing P0, P2 and MAG, and in B cells secreting IgG antibodies against P0 and P2. On day 14 after nerve biopsy these differences were no longer seen. We suggest that in patients with polyneuropathy, sural nerve biopsy with the ensuing wallerian degeneration and myelin breakdown causes transiently increased levels of circulating myelin autoreactive T and B cells. It remains to be determined if this has a physiological role in nerve trauma responses and/or affects the clinicopathological course of the peripheral neuropathy.

Myasthenia gravis: T and B cell reactivities to the beta-bungarotoxin binding protein presynaptic membrane receptor.

Antibodies against acetylcholine receptor (AChR) can be detected in most patients with myasthenia gravis (MG) and are considered to be involved in the immunopathogenesis of this disease. AChR are isolated from crude receptor preparations by binding to alpha-bungarotoxin (alpha-BuTx). Patients with MG have also antibodies against a second protein tentatively named presynaptic membrane receptor (PsmR), which has been isolated from crude receptor utilizing beta-bungarotoxin (beta-BuTx). PsmR could represent another antigen besides AChR relevant for the development of MG. We have now evaluated the T cell reactivity to PsmR in MG and controls by analysing the frequencies of cells which in response to PsmR in short-term cultures secreted interferon-gamma (IFN-gamma). The B cell response to PsmR was analysed in parallel by counting cells secreting anti-PsmR antibodies. Most patients with MG had PsmR reactive T cell in blood with a median number of about 1 per 44,000 mononuclear cells. Cells secreting anti-PsmR antibodies belonging to the IgG and IgA isotypes, less frequently of the IgM isotype were detected in most MG patients. A positive correlation was found between T cells reactive with PsmR and anti-PsmR IgG antibody secreting cells. PsmR reactive T and B cells were also detected in control patients, but at much lower numbers. Our results indicate that MG is accompanied by T as well as B cell responses to PsmR, in addition to the previously recognized responses to AChR. It remains to be shown whether these PsmR reactivities are of pathogenetic importance in MG.

Recommended diagnostic criteria for occupational chronic lead poisoning.

The present study aims to recommend the normal upper limit, the acceptable upper limit, the subclinical lead absorption and intoxication diagnostic criteria in an effort to re-evaluate the current national diagnostic criteria for the occupational chronic lead poisoning. The study was conducted on 330 lead exposed workers and 100 non-exposed controls based on the determination of blood and urinary lead, porphyrin metabolism indices, as well as other indices under a nationwide quality control program. The data were subsequently treated by the curve fitting, multi-step transformation to Gauss distribution, and discriminant analysis with the aid of a SAS software package. The relationships between the air lead and blood lead level with certain biological parameters indicative of excessive lead exposure and poisoning were well established. The sensitivity, specificity, accuracy, false positive and false negative results of these critical values were also fully evaluated. This study would be useful for the amendment of the new edition of the national diagnostic criteria for the occupational chronic lead poisoning in China and would provide new approaches for similar investigations.

Radiation hormesis: its expression in the immune system.

The effects of low-dose single and continuous whole-body irradiation on immune functions were studied in C57BL/6 mice. Plaque-forming cell reaction of the spleen was found to be stimulated by single doses of x rays in the range of 0.025 to 0.075 Gy and by continuous exposure to gamma rays with a cumulative dose of 0.065 Gy. The reactivity of thymocytes to interleukin 1 showed a dose-dependent depression in the dose range of 0.025 to 0.25 Gy, but there was an increase in cell number in the thymus between doses of 0.025 and 0.10 Gy, resulting in enhancement of reaction of the whole organ. Unscheduled DNA synthesis of spleen cells was stimulated by single irradiation with 0.05 Gy and continuous irradiation with a cumulative dose of 0.13 Gy. The implications of these immunologic changes under low-dose radiation are discussed.