bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of molecules involved in B lymphocyte survival and differentiation by synovial fibroblasts
Authors: EDWARDS J C W , LEIGH R D , CAMBRIDGE G 
Published: November 2003

SUMMARY
The synovitis of rheumatoid arthritis (RA) is one of few pathological lesions in which B lymphocyte accumulation progresses to the extent of germinal centre formation. The present study was designed to assess the ability of synovial fibroblasts to express molecules implicated in B lymphocyte survival and differentiation, both in vivo, and in response to cytokines in vitro. Normal and diseased synovia were examined by indirect immunofluorescence. In all tissues synovial intimal fibroblasts showed co-expression of vascular cell adhesion molecule-1 (VCAM-1) and complement decay-accelerating factor (DAF) comparable to that of follicular dendritic cells (FDC), but not complement receptor 2 (CR2). In rheumatoid synovia, subintimal cells showed variable expression of VCAM-1 and DAF, with bright co-expression of VCAM-1, DAF and CR2 in lymphoid follicle centres. B lymphocytes, some of which were proliferating cell nuclear antigen-positive, were present in contact with subintimal cells expressing VCAM-1 with or without DAF or CR2. B lymphocytes were rarely present in the intimal layer, and, where present, showed fragmentation. In vitro, synovial fibroblasts exposed to tumour necrosis factor-alpha (TNF-α) in combination with interferon-gamma (IFN-γ) showed enhanced expression of VCAM-1, in comparison with fibroblasts from skin and lung and, unlike skin and lung fibroblasts, also expressed DAF and CR2. These findings support the hypothesis that synovial targeting in RA involves an enhanced ability of synovial fibroblasts to support B lymphocyte survival. This appears to be dependent, not on the constitutive expression of VCAM-1 and DAF on intimal cells, but on the increased ability of subintimal cells to respond to proinflammatory cytokines, perhaps critically in the expression of VCAM-1.
Migration of human intestinal lamina propria lymphocytes, macrophages and eosinophils following the loss of surface epithelial cells
Authors: MAHIDA Y R , GALVIN A M , GRAY T , MAKH S , McALINDON M E , SEWELL H F , PODOLSKY D K 
Published: November 2003

SUMMARY
Lymphocytes and macrophages are present in the normal intestinal lamina propria, separated from the epithelial monolayer by the basement membrane. There is evidence for movement of mononuclear cells through the lamina propria, entering from the systemic circulation and exiting via lymphatic channels. The goal of our studies was to investigate the capacity of cells to migrate out from the lamina propria into the lumen following the loss of surface epithelial cells. An in vitro model was therefore established in which normal human intestinal mucosal samples, denuded of the surface epithelium, were maintained in culture. Electron microscopy showed that during culture, large numbers (&gt; 2 × 106/g tissue per 24 h) of cells migrated out of the lamina propria via discrete ‘tunnels’ which were in continuity with pores (diameter &lt; 4 μm) in the basement membrane. The emigrating cells were T cells (68.5 ± 5.1%), macrophages (10.5 ± 1.3%) and eosinophils (7.1 ± 1.3%). Our studies have therefore demonstrated, for the first time, the capacity for large numbers of lymphocytes, macrophages and eosinophils to migrate out of the lamina propria, via basement membrane pores. We postulate that such emigration of cells occurs in vivo following the loss of surface epithelial cells due to injury, and could represent an important form of host defence against luminal microorganisms and also facilitate wound repair by enhancing restitution by neighbouring epithelial cells, via peptide factors.
Hypogammaglobulinaemia occurs in Fas-deficient MRL-lpr mice following deletion of MHC class II molecules
Authors: ANDERSON C C , MUKHERJEE R , SINCLAIR N R StC , JEVNIKAR A M 
Published: November 2003

SUMMARY
Fas (CD95)-mediated apoptosis in B and T cells is deficient in both human autoimmune lymphoproliferative syndrome and in MRL-lpr mice, a model for systemic lupus erythematosis (SLE). Autoimmune disease in these mice is associated with polyclonal B cell activation, increased serum immunoglobulin and autoantibodies. In non-autoimmune mice MHC class II is not required for normal serum immunoglobulin expression, and previously we have shown using MHC class II-deficient MRL-lpr mice (MRL-lpr Ab−/−) that generation of specific antibodies to DNA requires MHC class II-directed T cell help. In contrast, in the present study we demonstrate that MRL-lpr Ab−/−mice also have a profound reduction of total serum immunoglobulin levels, suggesting abnormal polyclonal regulation of B cells by MHC class II-directed T cells occurs in the autoimmune MRL-lpr strain. This abrogation of immunoglobulin production does not occur in MHC class II-deficient non-obese diabetic (NOD) mice, nor in MHC class I-deficient NOD or MRL-lpr mice. Reduced immunoglobulin levels in MRL-lpr Ab−/− mice were not due to a lack of B cells or to an increased loss of circulating immunoglobulin, but were associated with reduced numbers of surface IgG-positive B cells. These results define a general abnormal regulation of B cells in MRL-lpr mice through a process requiring MHC class II, and suggest that Fas deficiency may allow expansion of totally T-dependent B cells.
Identification and characterization of a DR4-restricted T cell epitope within chlamydia heat shock protein 60
Authors: DEANE K H O , JECOCK R M , PEARCE J H , GASTON J S H 
Published: November 2003

SUMMARY
An epitope within the 60 kD Chlamydia trachomatis heat shock protein (hsp) 60, recognized by a HLA-DRB1*0401-restricted T cell clone from a reactive arthritis patient, has been characterized. Stimulatory peptides contained a nine amino acid sequence (residues 38–46) predicted by algorithm to confer strong binding to DRB1*0401, with valine in the P1 position. The overall length of the peptide was critical for efficient recognition; peptides with at least one residue N-terminal to the putative P1 position were markedly more stimulatory than a peptide whose N-terminal is the P1 valine. Optimal responses were seen with 14mer peptides having two to three amino acids N- and C-terminal to the core 9mer. The sequence of the defined epitope is identical in hsp60 from both C. trachomatis and C. pneumoniae. Since the latter is a common respiratory pathogen, patients infected with C. trachomatis may already be primed for responses to hsp60 by prior infection with C. pneumoniae. Such secondary responses are important in the pathogenesis of chlamydia-induced inflammatory diseases such as trachoma. Priming by infection with enteric organisms was considered because of the similarity of the epitope sequence in Escherichia coli hsp60. However, although an E. coli-related peptide was recognized, intact E. coli hsp60 was not, suggesting that the epitope is cryptic in E. coli hsp60. Human hsp60 has six amino acid differences from chlamydial hsp60 in the epitope sequence and was not recognized. Thus cross-reactive recognition of self hsp60 could not be implicated in the pathogenesis of chlamydia-induced reactive arthritis in this patient.
Pituitary responsiveness to GH‐releasing hormone, GH‐releasing peptide‐2 and thyrotrophin‐releasing hormone in critical illness
Authors: Van den Berghe Greet , De Zegher Francis , Bowers Cyril Y. , Wouters Pieter , Muller Peter , Soetens Filip , Vlasselaers Dirk , Schetz Miet , Verwaest Charles , Lauwers Peter , Bouillon Roger 
Published: November 2003

OBJECTIVE Protein hypercatabolism and preservation of fat depots are hallmarks of critical illness, which is associated with blunted pulsatile GH secretion and low circulating IGF‐I, TSH, T4 and T3. Repetitive TRH administration is known to reactivate the pituitary‐thyroid axis and to evoke paradoxical GH release in critical illness. We further explored the hypothalamic‐pituitary function in critical illness by examining the effects of GH‐releasing hormone (GHRH) and/or GH‐releasing peptide‐2 (GHRP‐2) and TRH administration. PATIENTS AND DESIGN Critically ill adults (n=40; mean age 55 years) received two i.v. boluses with a 6‐hour interval (0900 and 1500 h) within a cross‐over design. Patients were randomized to receive consecutively placebo and GHRP‐2 (n=10), GHRH and GHRP‐2 (n=10), GHRP‐2 and GHRH+GHRP‐2 (n=10), GHRH+GHRP‐2 and GHRH+GHRP‐2+TRH (n=10). The GHRH and GHRP‐2 doses were 1μg/kg and the TRH dose was 200μg. Blood samples were obtained before and 20, 40, 60 and 120 minutes after each injection. MEASUREMENTS Serum concentrations of GH, T4, T3, rT3, thyroid hormone binding globulin (TBG), IGF‐I, insulin and cortisol were measured by RIA; PRL and TSH concentrations were determined by IRMA. RESULTS Critically ill patients presented a striking GH response to GHRP‐2 (mean±SEM peak GH 51±9 μg/l in older patients and 102±2μg/l in younger patients; P=0.005 vs placebo). The mean GH response to GHRP‐2 was more than fourfold higher than to GHRH (P=0.007). In turn, the mean GH response to GHRH+GHRP‐2 was 2.5‐fold higher than to GHRP‐2 alone (P=0.01), indicating synergism. Adding TRH to the GHRH+GHRP‐2 combination slightly blunted this mean response by 18% (P=0.01). GHRP‐2 had no effect on serum TSH concentrations whereas both GHRH and GHRH+GHRP‐2 evoked an increase in peak TSH levels of 53 and 32% respectively. The addition of TRH further increased this TSH response < ninefold (P=0.005), elicited a 60% rise in serum T3 (P=0.01) and an 18% increase in T4 (P=0.005) levels, without altering rT3 or TBG levels. GHRH and/or GHRP‐2 induced a small increase in serum PRL levels. The addition of TRH magnified the PRL response 2.4‐fold (P=0.007). GHRP‐2 increased basal serum cortisol levels (531±29nmol/l) by 35% (P=0.02); GHRH provoked no additional response, but adding TRH further increased the cortisol response by 20% (P=0.05). CONCLUSIONS The specific character of hypothalamic‐pituitary function in critical illness is herewith extended to the responsiveness to GHRH and/or GHRP‐2 and TRH. The observation of striking bursts of GH secretion elicited by GHRP‐2 and particularly by GHRH+GHRP‐2 in patients with low spontaneous GH peaks opens the possibility of therapeutic perspectives for GH secretagogues in critical care medicine.
Bone turnover and bone mineral density in patients with congenital adrenal hyperplasia
Authors: Guo C‐Y. , Weetman A. P. , Eastell R. 
Published: November 2003

BACKGROUND AND OBJECTIVE Glucocorticoid replacement is the most effective therapy for patients with congenital adrenal hyperplasia (CAH). It has been reported that excessive steroid therapy leads to bone loss and osteoporosis, but it is uncertain whether steroid replacement therapy affects bone turnover and bone mineral density (BMD) in adult patients with CAH. DESIGN Case‐control study: patients with CAH were compared to normal subjects, individually matched for age and body weight. PATIENTS Eleven patients, aged 19–65 years, were evaluated in this study. The age at diagnosis of CAH was 0–26 years. Nine patients (6 females and 3 males) were diagnosed with 21‐hydroxylase deficiency and 2 male patients with 11‐hydroxylase deficiency. 17‐Hydroxyprogesterone levels in patients had never been below the reference range in the previous 2 years. These patients were individually matched for sex, age and weight to 11 healthy controls. MEASUREMENTS Total body, lumbar spine and femoral neck BMD was measured by dual‐energy X‐ray absorptiometry. Serum bone Gla‐protein (BGP, osteocalcin) and bone alkaline phosphatase (BAP) were measured to assess bone formation whereas serum tartrate‐resistant acid phosphatase (TRAP) and urinary cross‐linked N‐telopeptides of type I collagen (NTx) were measured to assess bone resorption. NTx was expressed as a fraction of urinary creatinine excretion (NTx/Cr). Serum dehydroepiandrosterone sulphate (DHEA‐S) and androstenedione levels were measured to assess adrenal androgen status. RESULTS Serum DHEA‐S, androstenedione, BGP and BAP and urinary NTx/Cr were decreased in patients when compared with controls (paired t‐test, P = 0.005, 0.0003, 0.002, 0.03 and 0.03, respectively). BMD was not significantly decreased in patients. The difference of total body BMD between patients and controls (i.e. BMD in patients minus BMD in controls) was negatively correlated with age. There was no correlation between androgen levels and either BMD or bone turnover. The total dose of steroid taken in the previous 2 years was not correlated with BMD, bone turnover or androgen levels. The was no correlation between BMD adjusted by age and bone turnover or initial age at diagnosis. CONCLUSIONS We conclude that (1) bone turnover is decreased in congenital adrenal hyperplasia, (2) bone mineral density is not decreased in congenital adrenal hyperplasia and (3) patients initially have higher bone mineral density but later have lower bone mineral density than controls, especially in women.
Ambulatory blood pressure profiles and plasminogen activator inhibitor (PAI‐1) activity in lean women with and without the polycystic ovary syndrome
Authors: Sampson Michael , Kong Chiew , Patel Anita , Unwin Robert , Jacobs Howard S. 
Published: November 2003

OBJECTIVE Hyperinsulinaemic women with the polycystic ovary syndrome (PCOS) may be at increased risk of vascular disease later in life, mediated by blood pressure or lipid abnormalities or by elevated plasma levels of plasminogen activator inhibitor‐1 (PAI‐1) activity. PAI‐1 may also be involved in ovarian follicle development and ovarian connective tissue remodelling. We measured plasma PAI‐1 activity and 24‐hour ambulatory blood pressure records in women with and without PCOS. DESIGN Cross‐sectional study of three groups. PATIENTS Twenty‐four non‐obese women with a classic ovarian ultrasound appearance of PCO and extreme menstrual disturbance (Group 1), 26 matched controls with a normal menstrual cycle and an ultrasound appearance of PCO (Group 2) and 10 matched controls with a normal menstrual cycle and normal ovarian ultrasound (Group 3). MEASUREMENTS Twenty‐four hour ambulatory blood pressure recordings (Spacelabs 90207), ovarian ultrasonography, fasting plasma insulin and glucose, plasma PAI‐1 activity, HDL and total cholesterol, triglycerides, gonadotrophins and testosterone. Family history of premature vascular disease. RESULTS Median fasting plasma insulin was significantly higher in Group 1 (45 .8 pmol/l, range 12.9–161.9) than in Group 2 (28.1 pmol/l; range 13.6–91; P <0.05) or Group 3 (26.0 pmol/l; range 13.5–63.3; P <0.05). There were no differences between groups in 24‐hour, daytime or night‐time ambulatory blood pressure measurements, and no relation between plasma insulin and any blood pressure variable.  Mean plasma PAI‐1 activity was higher in Group 1 (10.0 ±7.1 AU/l) than in Group 2 (6.0 ±4.6 AU/l P < 0.05) or Group 3 (5.1 ± 3.5 AU/l; P =0.06). There was a significant independent direct relation between fasting plasma insulin and PAI‐activity (r = 0.41, R2 = 0.154; F1,59 = 11.38; P = 0.001). Groups did not differ in parental history of premature vascular disease, or in mean HDL or fasting triglyceride levels. CONCLUSIONS The only measurable vascular risk factor associated with hyperinsulinaemia and menstrual disturbance in non‐obese women with PCOS is an elevated plasma PAI‐1 activity. These women did not differ from controls in ambulatory blood pressure profiles, lipid measurements or in a parental history of premature vascular disease. PAI‐1 and plasminogen are involved in ovarian follicle maturation and the present finding suggests a biologically plausible link between hyperinsulinaemia, anovulation and vascular risk in PCOS.
Plasma cortisol, PRL, ACTH, AVP and corticotrophin releasing hormone responses to direct current cardioversion and electroconvulsive therapy
Authors: Florkowski C. M. , Crozier I. G. , Nightingale S. , Evans M. J. , Ellis M. J. , Joyce P. , Donald R. A. 
Published: November 2003

OBJECTIVE We aimed to evaluate and contrast the hypothalamo–pituitary–adrenal (HPA) response to direct current (DC) cardioversion and electroconvulsive therapy (ECT).SUBJECTS Six male subjects (mean age 61.2 years, range 46–74) with chronic atrial fibrillation were selected for cardioversion. Six subjects with depression (one male, five female; mean age 43.2 years, range 31–59) were selected for ECT. Those taking glucocorticoid drugs, opiates or β‐adrenoceptor antagonists were excluded.MEASUREMENTS Patients attended for serial blood sampling on the day of cardioversion or ECT, and for an equivalent time period on a control day at least one week before. Intravenous propofol was given to each subject for anaesthesia on the day of cardioversion or ECT. On both study and control days, blood samples were taken at −30, −15, 0 (just prior to cardioversion or ECT), +5, +10, +15, +30, +60, +90 and +120 minutes for assay of cortisol, PRL, ACTH, AVP and CRH.RESULTS  For cardioversion: plasma cortisol increased from 252.5 ± 39.8 to a maximum of 721.3 ± 50 nmol/l at 30 minutes (P < 0.0001 compared with control day). ACTH increased from 12.8 ± 2.8 to a maximum of 64 ± 14 pmol/l at 5 minutes (P < 0.0001 compared with control day). AVP increased from 6.6 ± 3.3 to a maximum of 42.9 ± 16 pmol/l at 5 minutes post‐cardioversion (P < 0.005 compared with control day). PRL increased from 141 ± 28 mIU/l to a maximum of 873 ± 219 mIU/l at 10 minutes (P < 0.001 compared with control day). There was no significant difference in CRH responses between cardioversion and control days. There was no significant correlation between total electrical energy delivered and maximum ACTH and AVP responses (R = 0.54 and −0.13, respectively).  For ECT: on the day of ECT plasma cortisol increased from 419.5 ± 25.9 to a maximum of 614.7 ± 26.9 nmol/l (P < 0.002 compared with control day). ACTH increased from 22.7 ± 6.2 to a maximum of 77.8 ± 19.1 pmol/l (P < 0.0003 compared with control day). PRL increased from 771 ± 317 to a maximum of 3152 ± 703 mIU/l (P < 0.001 compared with control day, and significantly greater than the peak response to cardioversion, P < 0.03). AVP increased from 13.0 ± 10.8 to a maximum of 35.1 ± 5.6 pmol/l (P < 0.02 compared with control day). There was no significant difference in CRH responses between ECT and control days. Peak cortisol and ACTH responses did not differ significantly between ECT and cardioversion. Baseline cortisol levels, however, were significantly higher in the depressed group compared with the cardioversion group, P < 0.02, but not ACTH or AVP.CONCLUSION  Significant hypothalamic–pituitary–adrenal activation and PRL release occur in response to both cardioversion and ECT. AVP may have an important role in mediating the acute ACTH response to electrical stimulation.
Kallikrein gene expression in human pituitary tissues
Authors: Clements Judith A. , Mukhtar Annie , Verity Karen , Pullar Michael , McNeill Peter , Cummins James , Fuller Peter J. 
Published: November 2003

OBJECTIVE The glandular kallikreins are a family of enzymes involved in the post‐translational processing of polypeptides. Three family members have been characterized in the human: glandular kallikrein (KLK1) and two genes expressed in the prostate, KLK2 or hGK1 and KLK3 or prostate specific antigen (PSA). Both kallikrein immunoreactivity and KLK1 mRNA have been detected in the rat anterior pituitary and oestrogen induced prolactinomas. Immunoreactive kallikrein has also been reported in prolactin secreting pituitary tumours in humans. In this study we wished to determine whether KLK1 and/or other KLK genes were expressed in human pituitary tumours.DESIGN AND PATIENTS Retrospective analysis of KLK gene expression in pituitary tissue obtained at surgery from 11 patients with a range of pituitary syndromes, 10 of which were tumour induced and included four prolactinomas. Three normal pituitaries, obtained at necropsy, were also analysed.MEASUREMENTS Pituitary total RNA was subjected to both Northern blot analysis, with KLK1 and KLK2 cDNA probes, and KLK‐specific reverse transcriptase—polymerase chain reaction (RT‐PCR).RESULTS No KLK1 gene expression was detected on Northern blot analysis although expression of PRL, GH and pro‐opiomelanocortin (POMC) was variously detected. KLK RT‐PCR coupled with Southern blot analysis using oligonucleotide probes specific for each of the three KLK genes was positive in many tumours but with varying levels and differential expression. Overall, KLK1 was the most abundant with KLK3 the least. The identity of KLK1 and KLK2 was confirmed by sequencing the PCR products. There was no obvious correlation between KLK1 and hormone gene expression; KLK1 was present in PRL positive and negative tumours and in normal pituitary tissue.CONCLUSIONS We have demonstrated a low level of expression of KLK1 as well as KLK2 and KLK3 in the human pituitary. The expression of KLK2 and KLK3 in the pituitary is a novel finding. The lack of correlation between PRL and KLK1 gene expression is an unexpected finding suggesting that the interaction between these factors may be more complex in the human pituitary than in the rodent model.
Growth hormone‐binding protein related immunoreactivity is regulated by the degree of insulinopenia in diabetes mellitus
Authors: Kratzsch J. , Kellner K. , Zilkens T. , Schmidt‐Gayk H. , Selisko T. , Scholz G. H. 
Published: November 2003

OBJECTIVE Derangements in the GH/IGF axis are common in patients with diabetes mellitus. In insulin‐dependent diabetes mellitus (IDDM), these disturbances seem to be due to a partial defect in GH action on its own receptor or via a post‐receptor defect. In non‐insulin‐dependent diabetes mellitus (NIDDM), data are limited, and the regulation of the GH receptor (GHR) remains unclear. However, animal studies with diabetic rats demonstrated that the GHR density may be influenced by insulin disposal at the hepatocyte. With respect to this hypothesis we studied the relation between peripheral insulin status and the serum GH‐binding protein (GHBP), which reflects indirectly the GHR density in the tissues. Patients with IDDM were compared to a NIDDM group as well as to a group of healthy subjects. DESIGN AND PATIENTS Basal blood samples for the determination of serum GHBP, GH, and IGF‐I were obtained from patients with IDDM (n = 27), subjects with NIDDM (n = 112) and healthy controls (n = 42). Insulin, proinsulin, C‐peptide and IGF‐binding protein 1 (IGFBP‐1) serum levels were used to estimate the insulin status in diabetic patients. RESULTS GHBP serum levels were significantly lower in patients with IDDM than in either NIDDM or controls (P < 0.001). Conversely, the IGF‐I levels were reduced in both groups of diabetics. A subgroup of hypoinsulinaemic NIDDM patients showed significantly decreased GHBP concentrations (P < 0.05) compared to the NIDDM subgroup with hyperinsulinaemia. Furthermore, GHBP levels were significantly decreased in insulin‐treated patients with NIDDM compared to either non‐insulin‐requiring subjects or normal controls (P < 0.05). A significant direct relation was found between levels of GHBP and total insulin dose (P < 0.01) in patients with IDDM. In the NIDDM group, GHBP was correlated with proinsulin (P < 0.001), C‐peptide (P < 0.01), insulin (P < 0.05) and inversely with IGFBP‐1 (P < 0.001). Multiple linear regression analysis indicated a significant contribution of proinsulin and IGFBP‐1 to the variation of GHBP. CONCLUSIONS Decreased GHBP levels in IDDM as well as in NIDDM correlate with insulinopenia. Since the degree of insulinopenia depends on the capability of the β‐cells to secrete proinsulin, C‐peptide and insulin, we hypothesize that these hormones at least partially influence the serum level of GHBP. Low GHBP levels may reflect a reduced GH receptor density and a concomitant GH insensitivity, which leads to an impaired IGF generation in insulin‐deficient patients.