HLA-DR4 in ankylosing spondylitis with different patterns of joint involvement

Fifty patients with ankylosing spondylitis (AS) confined to the spine and sacroiliac joints were compared with 50 cases of AS complicated by various patterns of non-axial joint involvement. Radiological and clinical features were evaluated and HLA-DR4 typing was carried out. This antigen was found in 16% of 200 normal individuals in 18% of patients suffering from exclusively axial AS, and in 54% of patients with additional purely peripheral joint involvement (wrist, finger, ankle, toe). The possibility that HLA-DR4 represents a non-specific marker for peripheral arthritis in patients with ankylosing spondylitis is discussed.

The mechanism of inhibition and "reversal" of mitogen-induced lymphocyte activation in a model of purine-nucleoside phosphorylase deficiency

Purine-nucleoside phosphorylase (PNP) is a purine degradative enzyme that catalyzes the phosphorolysis of (deoxy) inosine or (deoxy) guanosine to their respective bases and (deoxy) ribose 1-phosphate. A severe T-cell immune deficiency syndrome with hypouricemia is associated with impaired PNP function. To study the biochemical basis for this syndrome we created an in vitro model of PNP deficiency in mitogen (phytohemagglutinin)-stimulated normal human peripheral blood lymphocytes using guanosine to competitively inhibit deoxyguanosine phosphorolysis. Guanosine-induced guanine toxicity was reversed by adenine. Under these conditions, deoxyguanosine (5-45 microM) diminished mitogen stimulation to 30% of control while increasing the deoxyguanosine triphosphate pool (dGTP) by over 20-fold. Deoxycytidine reversed deoxyguanosine toxicity with a diminution of dGTP accumulation, but no significant change in the deoxycytidine triphosphate pool. Thymidine reversed the deoxyguanosine toxicity, repleted the thymidine triphosphate (dTTP) pool, and caused an even further increase in the accumulation of dGTP. These data support a model of lymphotoxicity in PNP deficiency based on dGTP accumulation with inhibition of ribonucleotide reductase and depletion of the thymidine triphosphate pool. Thymidine triphosphate depletion is reversed by either deoxycytidine or thymidine; however, the former diminishes dGTP accumulation (probably by competition for phosphorylation) and the latter potentiates dGTP accumulation (probably through feedback augmentation of guanosine diphosphate (GDP) reduction by ribonucleotide reductase secondary to an increased dTTP pool).

The mechanism of inhibition and "reversal" of mitogen-induced lymphocyte activation in a model of adenosine deaminase deficiency

The biochemical mechanism of lymphocyte dysfunction with adenosine deaminase deficiency has been investigated using cultured phytohemagglutinin stimulated normal peripheral blood lymphocytes and the adenosine deaminase (ADA) inhibitor 2'-deoxycoformycin. The addition of deoxyadenosine to ADA-inhibited (but not to uninhibited) cells generated increased dATP pools (up to 50-fold greater than controls) and depressed the mitogen response. dATP Accumulation was accompanied by depletion of the other three deoxynucleoside triphosphate (dNTP) pools (dTTP, dCTP, and dGTP). Suppression of the mitogen response could be prevented ("reversed") to 90% of control levels by the addition of deoxynucleoside precursors for the depleted dNTPs at the initiation of mitogen stimulation. "Reversal" restored the dTTP and possibly the dGTP pools. Thus the mechanism of toxicity in this model appears to be inhibition of ribonucleotide reductase by massive accumulation of dATP, resulting in starvation for the other three deoxyribonucleoside triphosphates. "Reversibility" of this toxicity by providing sources for the missing three deoxynucleoside triphosphates argues for ribonucleotide reductase inhibition rather than other mechanisms of deoxyadenosine toxicity in this model.

[Ankylosing spondylitis with and without peripheral joint involvement. The significance of HLA-DR4 in the diagnosis, disease risk and pathogenesis]

50 patients with ankylosing spondylitis without any peripheral arthritis are compared with 50 cases of ankylosing spondylitis complicated by arthritis of different kind. Radiological and clinical features were evaluated and assessed. HLA-DR4 typing was carried out. This antigen was found in 16% of 200 normal individuals, in 18% of all patients with ankylosing spondylitis confined to the spinal column, and in 54% of patients with only peripheral arthritis (wrist, finger, ankle, toe joints). The conclusion that HLA-DR4 represents nonspecific evidence for peripheral arthritis in patients with ankylosing spondylitis is discussed.

Gold therapy in patients with systemic lupus erythematosus

Despite a progressively more favorable prognosis in systemic lupus erythematosus (SLE) a need remains for therapeutic agents with greater benefit and less toxicity than corticosteroids and immunosuppressive drugs. Therefore, we treated 16 patients with SLE but without renal diseases with auranofin, a drug with proved efficacy and safety in rheumatoid arthritis. A modest diminution in overall disease activity, as judged by the investigators, and a reduction in maintenance corticosteroid dosage was achieved. However, neither laboratory assessments nor more objective clinical measurements of SLE disease activity disclosed any improvement over baseline. One case each of proteinuria and thrombocytopenia was observed, most likely related to underlying disease and not the drug, suggesting that auranofin may be safe in patients with SLE. A controlled trial, utilizing a broader spectrum of patients with SLE, may be warranted.

Cholinergic stimulation of pancreatic polypeptide release by a meal, bombesin, neurotensin, tetragastrin, cholecystokinin, and cerulein

It has been demonstrated that pancreatic polypeptide (PP) release can be markedly impaired by vagotomy or anticholinergic drugs. The current studies examine the role of cholinomimetic stimulation on PP release in dogs. Eight conscious animals underwent a series of tests: (1) a test meal (10 g/kg Alpo); (2) tetragastrin infusion (4 micrograms/kg/hr); (3) bombesin infusion (1.0 microgram/kg/hr); (4) cerulein infusion (100 ng/kg/hr); (5) cholecystokinin octapeptide (CCK-OP) infusion (100 ng/kg/hr); (6) neurotensin infusion (3 ng/kg/hr). All the studies were repeated individually with intravenous bethanecol (100 micrograms/kg/hr) as the background stimulant. The mean increment of PP released by a meal (160 +/- 32 fmol/ml) was significantly increased by bethanecol infusion (316 +/- 49 fmol/ml) (P less than 0.05). Each individual peptide released a significant amount of PP; tetragastrin: 53 +/- 11; neurotensin: 58 +/- 14; CCK-OP: 42 +/- 9; cerulein: 42 +/- 12; bombesin: 118 +/- 24 (P less than 0.05). Bethanecol did not significantly augment PP release by any of the individual peptides (P greater than 0.05). This study indicates that PP release by a meal is sensitive to cholinomimetic stimulation and that the peptide involved is neither gastrin, neurotensin, CCK, bombesin, nor cerulein. These data support the possibility of the existence of a cholinergic stimulatable mechanism, possibly a peptide responsible for the release of PP.

Bombesin and insulin-stimulated pancreatic polypeptide release as a discriminator of vagal integrity

Intact vagi after ulcer operations are often implicated in the cause of recurrent ulcer. The stimulation of gastric acid by insulin hypoglycemia is dangerous and the measurement of acid secretion after gastrectomy unreliable. This study was undertaken to assess and compare PP release by bombesin or insulin as an indicator of vagal integrity. Eight dogs with a chronic gastric fistula were tested with bombesin (100 nanograms per kilogram) and insulin (0.1 unit per kilogram) intravenous bolus after unilateral and, then, bilateral truncal vagotomy. Each study was 120 minutes, and blood was taken at one, three, five, seven and then ten minute intervals. Gastric acid was measured by autobiuret titration. Plasma was stored at minus 20 degrees C. until assayed for PP by radioimmunoassay. Bombesin-stimulated gastric acid secretion was not significantly altered by vagotomy (p greater than 0.05), whereas that stimulated by insulin was significantly inhibited by bilateral truncal vagotomy (p less than 0.05). Bilateral and right hemivagotomy significantly inhibited PP release by bombesin (p less than 0.05), however, only bilateral truncal vagotomy significantly inhibited PP release by insulin (p less than 0.05). These results suggest that the measurement of PP release by insulin or bombesin is a sensitive index of vagal integrity and that bombesin-released PP may specifically delineate the integrity of the right vagus. Since the measurement of gastric acid secretion after operation is both uncomfortable and often difficult to interpret, the value of a simple blood test to determine vagal integrity may be of considerable clinical relevance.

Effect of rate-dependent left bundle branch block on global and regional left ventricular function

Seven subjects with rate-dependent left bundle branch block (RDLBBB) and 13 subjects with normal conduction (control group) underwent upright bicycle exercise radionuclide angiography to determine the effects of the development of RDLBBB on global and regional left ventricular function. Six of the seven subjects with RDLBBB had atypical chest pain syndromes; none had evidence of cardiac disease based on clinical examination and either normal cardiac catheterization or exercise thallium-201 scintigraphy. Radionuclide angiograms were recorded at rest and immediately before and after RDLBBB in the test group, and at rest and during intermediate and maximal exercise in the control group. The development of RDLBBB was associated with an abrupt decrease in left ventricular ejection fraction (LVEF) in six of seven patients (mean decrease 6 +/- 5%) and no overall increase in LVEF between rest and maximal exercise (65 +/- 9% and 65 +/- 12%, respectively). In contrast, LVEF in the control group was 62 +/- 8% at rest and increased to 72 +/- 8% at intermediate and 78 +/- 7% at maximal exercise. The onset of RDLBBB was associated with the development of asynchronous left ventricular contraction in each patient and hypokinesis in four of seven patients. All patients in the control group had normal wall motion at rest and exercise. These data indicate that the development of RDLBBB is associated with changes in global and regional ventricular function that may be confused with development of left ventricular ischemia during exercise.

Feline sarcoma virus-specific transformation-related proteins and protein kinase activity in tumor cells

Polyproteins (gag-fes) encoded by the Synder-Theilen (ST) and the Gardner-Arnstein (GA) strains of feline sarcoma virus (FeSV) were previously shown to be associated with mink or rat cells that were nonproductively transformed in vitro. In the present study we demonstrated that the same gag-fes proteins were found in cat cells transformed in vitro. Of greater importance, these transformation-related proteins were also in cells taken from fresh biopsies of FeSV-induced tumors. Cells from fibrosarcomas induced with ST-FeSV had gag-fes proteins that were characteristic of this strain. Fibrosarcomas and melanomas were induced with GA-FeSV and both types of tumors contained the protein that is characteristic of cells transformed in vitro with this virus. Expression of these proteins in cultured tumor cells appeared to be independent of the passage level. Based on two-dimensional tryptic peptide analysis, the gag-fes proteins of cat tumor cells appeared to be indistinguishable from those found in cells transformed in vitro. The polyproteins of the cat tumor cells have a closely associated protein kinase activity, as demonstrated in the in vitro assay, and phosphorylated tyrosine residues. Gag-fes proteins of either the ST or GA class were not present in cell cultures initiated from five spontaneous cat tumors.

Enucleation and the appearance of second primary tumors in cats bearing virally induced intraocular tumors

The effect of enucleation of an eye containing a malignant intraocular neoplasm on the occurrence of secondary tumors was studied in cats with tumors, mainly melanomas, induced by Gardner feline fibrosarcoma virus. Enucleation of eyes containing progressively growing tumors was followed by a sharp increase in the frequency of secondary tumors. Secondary tumors were detected in 13 of 14 (92.8%) cats subjected to enucleation but in only seven of 21 (33.3%) untreated cats. The data suggest that the secondary tumors were not metastases but rather second primary tumors induced by local transformation of fibrosarcoma virus shed from the intraocular neoplasms. The increased incidence of these second primary tumors in cats subjected to enucleation was associated with depressed antibody titers to a tumor-specific transplantation antigen, the feline oncornavirus-associated cell membrane antigen.

Opiate modulation of pancreatic polypeptide release by a meal in the dog

It has been reported that morphine abolished the plasma pancreatic polypeptide (PP) response to a meal in man, but the mechanism of this action is unclear. This study was designed to investigate the effect of low doses of the endogenous opiate peptide. Met-enkephalin and naloxone on basal- and meal-stimulated PP release in order to examine the role of opioid modulation in the release of this hormone. Four gastric fistula dogs underwent a series of six studies, a test meal alone. Met-enkephalin infusion (40 microgram/kg/hr), naloxone infusion, meal plus naloxone infusion and meal plus Met-enkephalin plus naloxone. Gastrin and PP were measured by radioimmunoassay. Basal PP levels averaged 35.1 +/- 3.0 fmol/ml. Although Met-enkephalin had no effect on basal PP levels, it significantly (P less than 0.05) inhibited the mean peak increment of PP stimulated by a meal (control, 331 +/- 39 fmol/ml; Met-enkephalin, 145 +/- 49 fmol/ml; P less than 0.05). This inhibition was completely abolished by naloxone. Naloxone alone did not alter basal- or meal-stimulated plasma PP levels. Neither Met-enkephalin nor naloxone altered basal or stimulated plasma gastrin levels. This study demonstrated that opiate peptides play a role in the regulation of the release of PP by a meal; it thus suggests the possibility of an opioid modulatory mechanism for the release of this hormone.

The early diagnosis of gastrinoma

Despite the increasing awareness of gastrinoma and its lethal peptic ulcer sequelae, the diagnosis is often initially missed or made as a terminal event. The authors screened all patients with peptic ulcer symptoms serious enough to warrant hospital admission or those associated with diarrhea, nephrolithiasis, hypercalcemia, or pituitary abnormality. In a one-year period (1979-1980) nine (of 14 suspected) new gastrinoma patients were identified using a sensitive and specific gastrin radioimmunoassay in combination with provocative tests including IV secretin, calcium, and food. Conventional upper GI series, CAT scan, arteriography, and endoscopy provided no additional information other than to confirm the presence of ulcer disease. Basal plasma gastrin levels were more than 200 pmol L-1 in only three of the nine (normal fasting plasma gastrin levels are less than 25 pmol L-1). Three patients presented with acute ulcer perforation, and the diagnosis of gastrinoma was suspected because of multiple ulcers and pancreatic masses. In three other patients, previous duodenal ulcer surgery had failed. One patient with dyspepsia, high basal plasma gastrin, negative secretin and calcium infusion studies, and a positive meal test was diagnosed as having G-cell hyperplasia; this was confirmed by biopsy and antral gastrin extraction. Antrectomy alone resulted in cure. In all patients tested, a positive calcium infusion or secretin bolus (greater than 100% rise over basal) strongly suggested the diagnosis of gastrinoma, which was confirmed at surgery. In the acute perforations, initial management with omental patch and cimetidine therapy allowed survival of two patients, while emergency total gastrectomy in the third resulted in death due to esophagojejunal leak. Elective patients were treated with cimetidine initially for at least two weeks before total gastrectomy. In this group there were no operative mortalities, and postoperative morbidity was minimal. This series illustrates three important points: (1) careful screening of an ulcer population using gastrin radioimmunoassay and provocative tests has enabled a high yield of gastrinomas while conventional investigations are of minimal values; (2) a high index of suspicion in appropriate cases is necessary; and (3) total gastrectomy performed under elective circumstances is safe and allows the patients to resume a normal and healthy life without the sequelae of aggressive peptic ulceration or daily drug administration.

Effect of methionine-enkephalin and naloxone on bombesin-stimulated gastric acid secretion, gastrin, and pancreatic polypeptide release in the dog

In four dogs with chronic gastric fistulae, bombesin infusion was used to stimulate the release of gastrin and pancreatic polypeptide (PP) as well as rates of gastric acid secretion. Neither methionine-enkephalin (met-enkephalin) nor naloxone alone or the combination of these agents altered bombesin-stimulated gastrin release. met-enkephalin alone (but not naloxone) significantly inhibited the gastric secretory response to bombesin, but this inhibitory effect was not influenced by the simultaneous infusion of naloxone; the data suggested that the effect of met-enkephalin was indirect, and perhaps modulated by another inhibitory mechanism. Whereas PP release induced by bombesin was not affected by naloxone, it was significantly suppressed by met-enkaphalin; since this inhibition was virtually totally reversed by naloxone, the data suggested that the effect of opiate peptides on the release of pancreatic polypeptide was direct and mediated by a specific opiate receptor.

Cholinergic modulation of substance P release

This study was initiated to evaluate mechanisms of release of immunoreactive substance P into the peripheral circulation and to determine whether these mechanisms are subject to cholinergic modulation. In conscious dogs, a high-protein meal significantly increased plasma concentrations of immunoreactive substance P from basal levels of 13.7 +/- 1.8 pg/ml to a peak of 20.1 +/- 2.8 pg/ml after which they returned to baseline. Prior atropinization (200 mg/kg) abolished this response and lowered the plasma levels to a nadir of 2.2 pg/ml at 20 min. Similarly, infusion of bombesin (17 ng/kg/min) increased peripheral venous substance P levels by 768 +/- 155 pg-min/ml for 120 min, whereas after prior treatment with atropine, bombesin released no significant amounts of this peptide (-10 +/- 134 pg-min/ml). The data support the concept that substance P release is under cholinergic control.

Retrospective longitudinal study of the rate of alveolar bone loss in humans using bite-wing radiographs

This study investigates the possible use of unstandardized bite-wing radiographs to determine the rate of alveolar bone loss over long periods of time. A total of 100 pairs of bite-wing radiographs obtained from patients of two general dental practitioners were read on a 3M Reader, normally used for reading microfilm. For the purpose of measurement, two reference points were selected on the teeth; the highest point on the occlusal surface of the crown, the mesial and distal points of the cemento-enamel junction. Both vertical and horizontal bone loss was measured. Initially bone levels on 20 full mouth bite-wing radiographs on all posterior teeth were measured, then in the next 80 cases, an abbreviated index was used. The bone heights were first examined at the beginning and then at the end of a 10-year time span. The percentages of measurable distances were 28% and 57%. From the Occlusal measurement point and the C E J measurement points, reasons for unreadability were also recorded. The annual rate of horizontal bone loss was 0.06 mm and 0.04 mm from the Occlusal reference point and the CEJ reference point. The rates for the vertical bone loss was 0.05 and 0.03 mm. In order to study whether there was a constant loss over a period of time, bone levels were measured in 10 successive years. The findings suggest that the bone loss rat per year fluctuated. The study suggests that the bite-wing radiographs can be used in longitudinal studies of periodontal disease and can provide important information on the natural history of the disease.

Evidence for an intestinal mechanism of pancreatic polypeptide release

The purpose of this study was to define the existence of an intestinal phase of pancreatic polypeptide (PP) release and to assess whether it was mediated by a cholinergic-sensitive mechanism. Four conscious dogs with 20-cm upper intestinal Thiry-Vella loops and chronic gastric fistulas were used. The Thiry-Vella (T-V) loops were perfused with 10% liver extract or 0.154 M NaCl at a rate of 1 ml/min for 120 min. In a separate experiment, 240 ml of 10% liver extract was infused over a 5-min period into the stomach via the gastric fistula. Basal PP levels were 29 +/- 4 fmol/ml. The gastric infusion of liver extract caused a significant increase of plasma PP levels to a peak of 215 +/- 29 fmol/ml (P less than 0.05). The perfusion of the T-V loop with liver extract significantly increased plasma PP levels over basal to a peak of 73 +/- 14 fmol/ml (P less than 0.05). This value was significantly less than that released by gastric infusion of liver extract (P less than 0.05). Perfusion of the loop with NaCl did not significantly alter basal plasma PP levels (P greater than 0.05). PP release by perfusion of the T-V loop with liver extract was abolished by atropine intravenous bolus (0.2 mg/kg). Although the combination of bethanechol (100 microgram/kg/hr intravenous) and liver extract consistently increased the plasma levels of PP, the values did not attain statistical significance when compared to liver extract alone (P greater than 0.05). The data presented are thus consistent with the hypothesis that there is an enteric phase of pancreatic polypeptide release and that this enteropancreatic reflex is mediated by a cholinergic-sensitive mechanism which might be hormonal or neural.

Retrovirus-encoded transformation-specific polyproteins: expression coordinated with malignant phenotype in cells from different germ layers

A transformation-associated polyprotein designated "gag-x" was previously shown to be induced by the feline sarcoma virus (FeSV) after the nonproductive transformation of rat or mink cells. We found that this protein was also expressed in cells derived from the native species (cat) with or without the production of feline leukemia helper virus (FeLV) and that cats could mount a humoral antibody response to the transformation-specific (x) portion of the molecule. Such antisera also reacted with the feline oncornavirus-associated cell membrane antigen (FOCMA) by membrane immunofluorescence. Expression of the gag-x protein was coordinated with malignant phenotype in that both transformed cat fibroblasts and cultured cells from a FeSV-induced melanoma expressed antigenically indistinguishable proteins of the same size. These cells are derived from different embryonic germ layers, suggesting that such transformation-related proteins may function in a pleiotropic manner when introduced by a virus.

Serum antibodies against feline oncornavirus-associated cell membrane antigen in cats bearing virally induced uveal melanomas

The humoral immune response to a virally induced feline model of human uveal melanoma was studied by examining sera from cats bearing iridal and choroidal melanomas for antibody to the feline oncornavirus-associated cell membrane antigen (FOCMA). Anti-FOCMA antibodies appeared earlier and in higher titers in cats that ultimately expressed nonprogressing uveal melanomas. By 8 weeks after virus inoculation 56% of the cats with nonprogressing lesions had anti-FOCMA antibodies, whereas only 7% of the cats with progressive tumors produced demonstrable antibodies against FOCMA. Mean serum antibody titers were approximately 10 times higher in cats with nonprogressive lesions than in cats with progressive tumors. Similar trends were observed throughout the 28-week study period. Early appearance and a high titer of serum antibody against FOCMA correlated with nonprogressing uveal melanoma. The results indicated that uveal melanomas could be immunogeneic and successfully managed by the host's immune system.

An in vitro investigation of genetic susceptibility to cancer in diploid fibroblasts from retinoblastoma patients

Thirty-two diploid fibroblast strains from individuals with the three forms of retinoblastoma were examined with an in vitro clonogenic survival assay to determine their sensitivity to killing by X rays. Strains from sporadic unilateral retinoblastoma patients and normal controls were indistinguishable from one another (group D0's = 147 +/- 15 rads and 146 +/- 5 rads, respectively) while the strains from patients with the hereditary form of the disease were significantly more X-ray sensitive (D0 = 111 +/- 12). Strains derived from individuals with the D-deletion form of the disease resembled the hereditary strains with respect to sensitivity and heterogeneity, suggesting a possible, common etiology for these two forms of the disease. A DNA-repair defect is hypothesized as reflected by the observed hypersensitivity to X-irradiation in these cells. We suggest that this defect may be associated with the enhanced frequency of spontaneous and radiation-induced second tumors seen in some retinoblastoma patients.

The effect of somatostatin and 16,16-dimethyl-prostaglandin E2 on bombesin-stimulated canine gastric acid, plasma gastrin and pancreatic polypeptide secretion

We studied the effect of the intravenous infusion of 16,16-dimethylprostaglandin E2 methyl ester (di-M-PGE2) and somatostatin on bombesin-stimulated gastric acid secretion, plasma gastrin and plasma pancreatic polypeptide in four chronic gastric fistula dogs. Bombesin-stimulated gastric acid secretion was significantly inhibited by somatostatin and virtually abolished by di-M-PGE2. Both agents caused significant, but indistinguishable inhibition of gastrin release (P less than 0.05). Bombesin-stimulated pancreatic polypeptide release was also significantly inhibited by both somatostatin and di-M-PGE2; the inhibitory effect of somatostatin was significantly greater than that of di-M-PGE2 (P less than 0.05). This study provides further evidence in support of the complex interrelationships between agents responsible for the modulation of gastrointestinal physiology.

Rubeosis iridis in "pseudogliomas"

A total of 85 eyes (75 patients) with pseudogliomas (i.e., certain conditions which simulate retinoblastoma, were examined histopathologically to determine the incidence of rubeosis iridis. Neovascularization of the anterior surface of the iris was found in 70 eyes (82%). The principal associated changes in these eyes were moderate to severe inflammation of the uveal tract and retinal detachment. These findings are interpreted as indicating that inflammation, retinal detachment, and/or ischemia are effective stimulants in producing iris neovascularization, and rubeosis is not a significant factor in differentiating eyes with retinoblastoma from those eyes with pseudogliomas.