Quantitative sensory testing, psychological profiles and clinical pain in patients with psoriatic arthritis and hand osteoarthritis experiencing pain of at least moderate intensity

BACKGROUND

Chronic pain is the hallmark symptom of joint diseases. This study examined the differences in quantitative sensory testing between patients with psoriatic arthritis (PsA), hand osteoarthritis (hand-OA) and a pain-free control group and differences between patients with and without concomitant fibromyalgia (cFM).

METHODS

All patients and pain-free controls were assessed using pressure pain thresholds (PPT), temporal summation of pain (TSP), conditioned pain modulation (CPM) and clinical pain intensities. Psychological distress was assessed with the Hospital Anxiety and Depression Scale, Pain Catastrophizing Scale, and Pittsburgh Sleep Quality Index. Disability was assessed with the Health Assessment Questionnaire and pain quality with the painDETECT questionnaire. cFM was identified using the revised 2016 American College of Rheumatology diagnostic criteria.

RESULTS

Patients with hand-OA (n = 75) or PsA (n = 58) had statistically significant lower PPTs and CPM, greater TSP, and higher scores of psychological distress (p < 0.05) than controls (n = 20). Patients with cFM (58%) had higher scores of depression (p = 0.001), anxiety (p = 0.004), catastrophizing (p = 0.012), disability (p < 0.001), higher painDETECT score (p = 0.001), TSP (p = 0.027), and reduced sleep quality (p = 0.021) when compared to patients without cFM.

CONCLUSION

Patients with hand-OA and PsA exhibited signs of pain sensitization and a higher degree of psychological distress and disability than pain-free individuals. Patients with cFM had greater TSP, painDETECT score, disability, catastrophizing, and reduced sleep quality, than patients without, indicating greater degree of pain sensitization, psychological burden, and disability.

STATEMENT OF SIGNIFICANCE

This paper shows that a significant proportion of patients with hand osteoarthritis and psoriatic arthritis with moderate pain intensity have significantly increased signs of pain sensitization and markers of psychological distress. A large proportion of these patients fulfil the criteria for concomitant fibromyalgia and these patients show even greater propensity towards pain sensitization and psychological distress.

POS1021 THE EFFECT OF CANNABIDIOL ON QUANTITATIVE SENSORY TESTING PARAMETERS IN PATIENTS WITH HAND OSTEOARTHRITIS AND PSORIATIC ARTHRITIS: A RANDOMIZED DOUBLE-BLIND PLACEBO-CONTROLLED TRIAL

Background

Cannabidiol (CBD) has been proposed as an analgesic/anti-inflammatory treatment modality for joint pain. This study is based on a randomised, placebo controlled, double blind study (NORDCAN), investigating the effect of CBD in patients with painful hand osteoarthritis or psoriatic arthritis [1].

Objectives

The aim of the present study was to investigate the effect of CBD on quantitative sensory testing (QST) parameters.

Methods

The present randomised, placebo controlled, double blind study included 128 patients with hand osteoarthritis or psoriatic arthritis with chronic pain of moderate intensity. The trial compared 12 weeks of 20-30 mg CBD treatment with placebo. The QST parameters were assessed at baseline and after treatment. Pressure pain thresholds was measured at the most painful finger joint (local site) and the shin of the right leg (distal non-painful site). Temporal summation of pain and conditioned pain modulation were assessed using computer-controlled cuff algometry with the tourniquets on lower leg at the level of the upper portion of the gastrocnemius.

Results

Baseline characteristics (demographics and pain) for the CBD treated group and placebo group were comparable. No significant differences were observed in QST variables between baseline and end of treatment when comparing CBD and placebo.

Conclusion

No differences in modulation in QST parameters were demonstrated in patients in treatment with 20-30 mg CBD compared to placebo. Further studies of patients with rheumatic diseases treated with different dosage of CBD are needed to clarify the effect of CBD on pain in this patient group.

References

[1]Vela J, Dreyer L, Petersen KK, Nielsen LA, Duch KS, Kristensen S. Cannabidiol treatment in hand osteoarthritis and psoriatic arthritis. Pain 2021;Publish Ah. doi:10.1097/j.pain.0000000000002466.

Figure 1.

Flow-diagram of participant in the NORDCAN study

Table 1.

Difference in QST outcomes after 12 weeks of treatment with CBD or placebo.

Placebo groupCBD groupDifference95% CIpDifference95% CIpPPT Joint, kPa*18.62-19 to 56.760.3242.561.95 to 86.310.03PPT Shin, kPa*35.02-8.72 to 78.760.115.88-30.12 to 41.890.75CPM, kPa3.23-2.11 to 8.580.173.92-1.75 to 9.590.17TSP0.18-0.58 to 0.940.640.12-0.41 to 0.650.63

* Assessed using handheld algometer.

Abbreviations: CPM, Conditioned pain modulation; PPT, Pressure pain threshold; TSP, Temporal summation of pain

Acknowledgements

The authors thank patients, research personnel, the patient research partners, the Danish Rheumatism Association and the Psoriasis Association for their contribution to the NORDCAN trial.

Disclosure of Interests

Jonathan Vela: None declared, Kristian Kjær Petersen: None declared, Lene Dreyer Grant/research support from: Has received research grants from BMS and honorariums from Eli Lilly, Galderma, and Janssen, Lars Arent-Nielsen Speakers bureau: Has received speaker and advisory fees from GSK, Pfizer and Grünenthal., Salome Kristensen: None declared

THU0473 IS PAIN INTENSITY ASSOCIATED WITH EARLY MORTALITY IN PATIENTS WITH PSORIATIC ARTHRITIS?

Background:

Studies regarding excess mortality among patients with psoriatic arthritis (PsA) are conflicting due to the heterogenous nature of the disease. Thus, identifying risk factors for mortality is crucial, but few studies have examined these in PsA. Presence of chronic pain can cause excess mortality and since pain is prevalent among patients with PsA this association should be explored.

Objectives:

To investigate whether higher cumulative pain intensity is associated with an excess mortality ratio in patients with PsA.

Methods:

A nested case-control study was performed using data from the national Danish healthcare registers and the DANBIO rheumatology register. Cases were patients who died while followed in routine care. Cases were matched on sex, year of birth and calendar period of DANBIO entry with up to five controls. The main exposure of interest was the mean pain intensity (all causes) reported during the time followed in routine rheumatology practice. The pain intensity was measured on a visual analogue scale (VAS) ranging from 0 (no pain) to 100 (worst imaginable pain). Conditional logistic regression was used to calculate the odds of mortality per 5 unit increase in VAS pain while adjusting for inflammatory markers.

Results:

The Danbio PsA cohort consisted of 8019 patients. In total, 266 cases, i.e. PsA patients who died during the observational period, were identified and matched with 1198 controls (4.5 controls per case). Increasing pain intensity was associated with increased odds of mortality (OR 1.05, 95%CI 1.01 to 1.09) in the crude model, but the association disappeared when adjusting for age, sex, calendar time, socioeconomic status, average c-reactive protein and swollen joint count during the observation period (OR 0.98, 95%CI 0.93-1.03).

Age, average CRP, biological DMARD use, glucocorticoid use, and comorbidities (see table) increased the odds of mortality.

Table

regression estimates from fully adjusted model

Odds Ratio95% CIAge2,731,60-4,68C-reactive protein1,051,03-1,07Swollen joint count1,080,97-1,22Health assessment questionnaire1,250,84-1,86bDMARD use2,621,51-4,57cDMARD use0,690,46-1,03Glucocorticoid use3,902,51-6,05Chronic obstructive pulmonary disease2,191,20-4,02Diabetes mellitus2,651,62-4,31Cancer6,153,88-9,76Cardiovascular disease2,611,71-3,97

Conclusion:

These results indicate that experienced pain in itself is not associated with excess mortality. Age, recent glucocorticoid use, biological DMARD use, chronic pulmonary disease, diabetes, cancer and cardiovascular disease were all associated with an increased mortality.

Disclosure of Interests: :

None declared

Political support for the institutionalization of health assessment within Environmental Impact Assessment

Health Impact Assessment (HIA) as a stand-alone report integrated in environmental impact assessment has been compulsory for the last 5 years in Andalusia. In this time, it has been proven as a successful tool for implementing the Health in All Policies strategy, delivering consistently better outcomes for the examined projects.

The effective implementation of HIA required huge institutional and political support as this choice was very controversial and sparked opposition from developers. They alleged it would worsen the adverse socioeconomic situation and made claims about how it would generate unfair competition for companies in the region.

Nevertheless, the main source of opposition was located within administrations, unaccustomed to collaborative work. There were also fears about the increased bureaucracy and lack of coordination in procedures. It was a major challenge, as it seemed conflicting with other political objectives as achieving economic growth and job creation, while offering doubtful political gains due to difficulty in achieving results in the short term.

The support implied assuming a political leadership focused on the inclusion of health in the government’s list of priorities, advocating for the population value as a strategic element. It also meant raising awareness among all sectors by searching for strategic alliances and being prepared to compromise and reach agreements.

It needed technical and organisational leadership too. First, by defining a feasible model of HIA, and then by building bridges between the different sectors. Regarding coordination, several joint instructions have been drawn up to clarify the activities that each organization must undertake, including deadlines and persons in charge. Finally, other successful strategies have been the development of facilitation mechanisms and the provision of specific training courses for developers and administrative staff.

Outcome of Patients with Venous Thromboembolism and Factor V Leiden or Prothrombin 20210 Carrier Mutations During the Course of Anticoagulation

BACKGROUND

Individuals with factor V Leiden or prothrombin G20210A mutations are at a higher risk to develop venous thromboembolism. However, the influence of these polymorphisms on patient outcome during anticoagulant therapy has not been consistently explored.

METHODS

We used the Registro Informatizado de Enfermedad TromboEmbólica database to compare rates of venous thromboembolism recurrence and bleeding events occurring during the anticoagulation course in factor V Leiden carriers, prothrombin mutation carriers, and noncarriers.

RESULTS

Between March 2001 and December 2015, 10,139 patients underwent thrombophilia testing. Of these, 1384 were factor V Leiden carriers, 1115 were prothrombin mutation carriers, and 7640 were noncarriers. During the anticoagulation course, 160 patients developed recurrent deep vein thrombosis and 94 patients developed pulmonary embolism (16 died); 154 patients had major bleeding (10 died), and 291 patients had nonmajor bleeding. On multivariable analysis, factor V Leiden carriers had a similar rate of venous thromboembolism recurrence (adjusted hazard ratio [HR], 1.16; 95% confidence interval [CI], 0.82-1.64), half the rate of major bleeding (adjusted HR, 0.50; 95% CI, 0.25-0.99) and a nonsignificantly lower rate of nonmajor bleeding (adjusted HR, 0.66; 95% CI, 0.43-1.01) than noncarriers. Prothrombin mutation carriers and noncarriers had a comparable rate of venous thromboembolism recurrence (adjusted HR, 1.00; 95% CI, 0.68-1.48), major bleeding (adjusted HR, 0.75; 95% CI, 0.42-1.34), and nonmajor bleeding events (adjusted HR, 1.10; 95% CI, 0.77-1.57).

CONCLUSIONS

During the anticoagulation course, factor V Leiden carriers had a similar risk for venous thromboembolism recurrence and half the risk for major bleeding compared with noncarriers. This finding may contribute to decision-making regarding anticoagulation duration in selected factor V Leiden carriers with venous thromboembolism.

The Clinical Course of Venous Thromboembolism May Differ According to Cancer Site

BACKGROUND

We hypothesized that the clinical course of venous thromboembolism in patients with active cancer may differ according to the specificities of primary tumor site.

AIM AND METHODS

We used data from RIETE (international registry of patients with venous thromboembolism) to compare the clinical venous thromboembolism-related outcomes during the course of anticoagulation in patients with one of the 4 more frequent cancers (breast, prostate, colorectal, or lung cancer).

RESULTS

As of September 2014, 3947 cancer patients were recruited, of whom 938 had breast, 629 prostate, 1189 colorectal, and 1191 lung cancer. Overall, 55% had metastatic disease (42%, 36%, 53%, and 72%, respectively). During the course of anticoagulant therapy (mean duration, 139 days), the rate of thromboembolic recurrences was similar to the rate of major bleeding in patients with breast (5.6 [95% confidence interval (CI), 3.8-8.1] vs 4.1 [95% CI, 2.7-5.9] events per 100 patient-years) or colorectal cancer (10 [95% CI, 7.6-13] vs 12 [95% CI, 9.4-15] per 100 patient-years). In contrast, in patients with prostate cancer, the rate of venous thromboembolic recurrences was half the rate of major bleeding (6.9 [95% CI, 4.4-10] vs 13 [95% CI, 9.2-17] events per 100 patient-years), whereas in those with lung cancer, the rate of thromboembolic recurrences was twofold higher than the rate of major bleeding (27 [95% CI, 22-23] vs 11 [95% CI, 8.6-15] per 100 patient-years).

CONCLUSIONS

Significant differences in the clinical profile of venous thromboembolic-related outcomes were observed according to the site of cancer. These findings suggest the development of cancer-specific anticoagulant strategies as an area for further research.

A prognostic score to identify low-risk outpatients with acute deep vein thrombosis in the lower limbs

BACKGROUND

No prior studies have identified which patients with deep vein thrombosis in the lower limbs are at a low risk for adverse events within the first week of therapy.

METHODS

We used data from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) to identify patients at low risk for the composite outcome of pulmonary embolism, major bleeding, or death within the first week. We built a prognostic score and compared it with the decision to treat patients at home.

RESULTS

As of December 2013, 15,280 outpatients with deep vein thrombosis had been enrolled. Overall, 5164 patients (34%) were treated at home. Of these, 12 (0.23%) had pulmonary embolism, 8 (0.15%) bled, and 4 (0.08%) died. On multivariable analysis, chronic heart failure, recent immobility, recent bleeding, cancer, renal insufficiency, and abnormal platelet count independently predicted the risk for the composite outcome. Among 11,430 patients (75%) considered to be at low risk, 15 (0.13%) suffered pulmonary embolism, 22 (0.19%) bled, and 8 (0.07%) died. The C-statistic was 0.61 (95% confidence interval [CI], 0.57-0.65) for the decision to treat patients at home and 0.76 (95% CI, 0.72-0.79) for the score (P = .003). Net reclassification improvement was 41% (P < .001). Integrated discrimination improvement was 0.034 for the score and 0.015 for the clinical decision (P < .001).

CONCLUSIONS

Using 6 easily available variables, we identified outpatients with deep vein thrombosis at low risk for adverse events within the first week. These data may help to safely treat more patients at home. This score, however, should be validated.

Near-unity quantum yields of biexciton emission from CdSe/CdS nanocrystals measured using single-particle spectroscopy

Biexciton photoluminescence (PL) quantum yields (Q(2X)) of individual CdSe/CdS core-shell nanocrystal quantum dots with various shell thicknesses are derived from independent PL saturation and two-photon correlation measurements. We observe a near-unity Q(2X) for some nanocrystals with an ultrathick 19-monolayer shell. High Q(2X)'s are, however, not universal and vary widely among nominally identical nanocrystals indicating a significant dependence of Q(2X) upon subtle structural differences. Interestingly, our measurements indicate that high Q(2X)'s are not required to achieve complete suppression of PL intensity fluctuations in individual nanocrystals.

Highly emissive multiexcitons in steady-state photoluminescence of individual "giant" CdSe/CdS Core/Shell nanocrystals

The development of nanocrystal quantum dots (NQDs) with suppressed nonradiative Auger recombination has been an important goal in colloidal nanostructure research motivated by the needs of prospective applications in lasing devices, light-emitting diodes, and photovoltaic cells. Here, we conduct single-nanocrystal spectroscopic studies of recently developed core-shell NQDs (so-called "giant" NQDs) that comprise a small CdSe core surrounded by a 16-monolayer-thick CdS shell. Using both continuous-wave and pulsed excitation, we observe strong emission features due both to neutral and charged biexcitons, as well as multiexcitons of higher order. The development of pronounced multiexcitonic peaks in steady-state photoluminescence of individual nanocrystals, as well as continuous growth of the emission intensity in the range of high pump levels, point toward a significant suppression of nonradiative Auger decay that normally renders multiexcitons nonemissive. The unusually high multiexciton emission efficiencies in these systems open interesting opportunities for studies of multiexciton phenomena using well-established methods of single-dot spectroscopy, as well as new exciting prospects for applications, that have previously been hampered by nonradiative Auger decay.

Trigeminal nociceptors express prostaglandin receptors

Orofacial inflammation is associated with prostaglandin release and the sensitization of nociceptive receptors such as the transient receptor potential subtype V(1) (TRPV(1)). We hypothesized that certain PGE(2) receptor subtypes (EP1-EP4) are co-expressed with TRPV(1) in trigeminal nociceptors and sensitize responses to a TRPV(1) agonist, capsaicin. Accordingly, combined in situ hybridization was performed with immunohistochemistry on rat trigeminal ganglia. We next evaluated the effects of specific EP2 and EP3 agonists (butaprost and sulprostone) in cultured trigeminal ganglia neurons. The results showed that EP2 and EP3 are expressed in trigeminal neurons (58% and 53% of total neurons, respectively) and are co-expressed in TRPV(1)-positive neurons (64% and 67 % of TRPV(1)-positive neurons, respectively). Moreover, most of the cells expressing EP2 or EP3 mRNA were of small to medium diameter (< 30 microm). The application of butaprost and sulprostone triggered neuropeptide exocytosis, and butaprost sensitized capsaicin responses. Analysis of these data, collectively, supports the hypothesis that prostaglandins regulate trigeminal TRPV(1) nociceptors via activation of the EP2 and EP3 receptors.

Dehydroepiandrosterone (DHEA) modulates GHRH, somatostatin and angiotensin II action at the pituitary level

In view of the present controversy related to the potential beneficial effects of clinical dehydroepiandrosterone (DHEA) treatments, and considering our own previous results that reveal an influence of this steroid in pituitary hyperplasia development in vivo in rats, we decided to evaluate the role of DHEA in prolactin and GH secretion, as well as in second messengers involved, in cultured rat anterior pituitary cells. DHEA (1 x 10(-5) to 1 x 10(-7) M) did not modify basal GH or prolactin release, and a prolactin inhibitory effect was observed only for androstenediol, a metabolite of DHEA. DHEA partially prevented dopamine (1 x 10(-6) M)-induced prolactin inhibition and facilitated the prolactin-releasing effect of 10(-8) M Ang II, without modifying the resulting Ca2+(i) mobilization. Furthermore, DHEA potentiated the GH release and cAMP production induced by 1 x 10(-8) M GHRH. Finally, DHEA partially reversed the inhibitory effect of 1 x 10(-8) M somatostatin on GH, but not prolactin, release. We conclude that DHEA in vitro, directly or indirectly through conversion into metabolites, is able to modulate the hormonal response of the pituitary to hypothalamic regulators. It can enhance pituitary prolactin release and induce GH secretion. These effects could help explain some of the side effects observed in prolonged DHEA treatments in vivo and should be taken into account when considering its use in human clinical trials.

Rapid PCR-mediated synthesis of competitor molecules for accurate quantification of beta(2) GABA(A) receptor subunit mRNA

We describe a fast and easy method for the synthesis of competitor molecules based on non-specific conditions of PCR. RT-competitive PCR is a sensitive technique that allows quantification of very low quantities of mRNA molecules in small tissue samples. This technique is based on the competition established between the native and standard templates for nucleotides, primers or other factors during PCR. Thus, the most critical parameter is the use of good internal standards to generate a standard curve from which the amount of native sequences can be properly estimated. At the present time different types of internal standards and methods for their synthesis have been described. Normally, most of these methods are time-consuming and require the use of different sets of primers, different rounds of PCR or specific modifications, such as site-directed mutagenesis, that need subsequent analysis of the PCR products. Using our method, we obtained in a single round of PCR and with the same primer pair, competitor molecules that were successfully used in RT-competitive PCR experiments. The principal advantage of this method is high versatility and economy. Theoretically it is possible to synthesize a specific competitor molecule for each primer pair used. Finally, using this method we have been able to quantify the increase in the expression of the beta(2) GABA(A) receptor subunit mRNA that occurs during rat hippocampus development.

Involvement of inducible isoforms of COX and NOS in streptozotocin-pancreatic damage in the rat: interactions between nitridergic and prostanoid pathway

Streptozotocin-induced pancreatic damage involves nitric oxide (NO) and prostaglandins (PGs) overproduction. In this work we aim to evaluate a putative relationship between the elevated NO levels and the altered prostanoid production in pancreatic tissue from streptozotocin-diabetic rats. Total NOS activity and nitrate/nitrite pancreatic levels in tissues from diabetic rats are decreased when the cyclooxygenase (COX) inhibitor indomethacin (INDO) is added to the incubating medium, while the addition of PGE(2)increases nitrate/nitrite production and NOS levels. INDO and PGE(2)selectively affect Ca(2+)-dependent NOS (iNOS) activity in diabetic tissues, and they have not been able to modify nitrate/nitrite levels, iNOS or Ca(2+)-dependent (cNOS) in control tissues. When the NOS inhibitor L-NMMA was present in the incubating medium, control pancreatic [(14)C]-Arachidonic Acid ([(14)C]-AA) conversion to 6-keto PGF(1 alpha)and to TXB(2)was lower, and PGF(2 alpha), PGE(2)and TXB(2)production from diabetic tissues diminished. The NO donors, spermine nonoate (SN) and SIN-1, enhanced TXB(2)levels in control tissues, while PGF(2 alpha), PGE(2)and TXB(2)levels from diabetic tissues were increased. PGE(2)production from control and diabetic tissues was assessed in the presence of the NO donor SN plus INDO or NS398, a specific PG synthase 2 inhibitor. When SN combined with INDO or NS398 was added, the increment of PGE(2)production was abolished by both inhibitors in equal amounts, indicating that the activating effect of nitric oxide is exerted on the inducible isoform of cyclooxygenase. In the diabetic rat, prostaglandins and NO seem to stimulate the generation of each other, suggesting a lack of regulatory mechanisms that control the levels of vasoactive substances in acute phase of beta-cell destruction.

Quantitative determination of clenbuterol, salbutamol and tulobuterol enantiomers by capillary electrophoresis

Enantiomers of clenbuterol, salbutamol and tulobuterol were directly separated and quantitated from a spiked sample by capillary electrophoresis (CE) using sulfaited beta-cyclodextrin (SCD) as chiral selector and phosphate as running buffer. The SCD and buffer concentration, pH and field strength were the parameters studied to optimize the separation. Optimal separation was obtained using 50 mM of phosphate monobasic at pH = 2.24, 0.25% (w/w) of sulfated cyclodextrin and a field strength of 10 kV, with 20 min total time analysis. Comparison between two different injection modes (hydrodynamic and electrokinetic) was made. In the hydrodynamic mode, repeatability (expressed as relative standard deviation, RSD) was less than 1.2% for migration times for all the analyte peaks and less than 2% for peak area percentages. With respect to reproducibility, RSD was less than 3.8% for migration time and less than 3% for peak area percentages. Calibration curves were set up for two different sample concentration ranges (1 to 10 microg mL(-1) and 160-800 ng mL(-1), of each of the racemates studied). Although the electrokinetic injection mode for an aqueous sample appeared to suffer from some enantiodiscrimination, calibration curves were linear in the range between 1 and 10 ng mL(-1) with regression coefficients ranging from 0.9996 to 0.9952. As in the case of hydrodynamic injection, the method was tested with a spiked sample.

Determination of hydrocarbon types in petroleum and coal-derived products by thin-layer chromatography/densitometry

Different methodologies based on thin-layer chromatography (TLC)/densitometry were used to separate and quantitate hydrocarbon types in middle distillates (gas oil), heavy distillates (lubricant) from petroleum, and coal-derived products. Thus, petroleum products were separated into saturates and aromatics by development, using n-hexane (9 min) followed by dichloromethane (4.5 min), of silica gel plates impregnated with berberine sulfate. Detection of saturates and aromatics was performed by fluorescence scanning using 365 nm as the excitation wavelength. Alternative detection of aromatics can be performed on either silica gel or berberine-impregnated plates by using ultraviolet (UV) densitometry at 250 nm. On the other hand, polar coal-derived products were separated into aromatics, polar compounds, and uneluted components by using silica gel plates and development with toluene (12 min), followed by dichloromethane-methanol (95 + 5, v/v), with detection by UV densitometry at 250 nm. In all cases, external standard calibration was used for quantitation. Results were validated by using standard methods or well-established techniques of the petrochemical industry. The potential usefulness of TLC/densitometry is discussed.

Pancreatic nitric oxide and oxygen free radicals in the early stages of streptozotocin-induced diabetes mellitus in the rat

The objective of the present study was to explore the regulatory mechanisms of free radicals during streptozotocin (STZ)-induced pancreatic damage, which may involve nitric oxide (NO) production as a modulator of cellular oxidative stress. Removal of oxygen species by incubating pancreatic tissues in the presence of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) (1 U/ml) produced a decrease in nitrite levels (42%) and NO synthase (NOS) activity (50%) in diabetic but not in control samples. When NO production was blocked by N(G)-monomethyl-L-arginine (L-NMMA) (600 microM), SOD activity increased (15.21 +/- 1.23 vs 24.40 +/- 2.01 U/mg dry weight). The increase was abolished when the NO donor, spermine nonoate, was added to the incubating medium (13.2 +/- 1.32). Lipid peroxidation was lower in diabetic tissues when PEG-SOD was added (0.40 +/- 0.02 vs 0.20 +/- 0.03 nmol/mg protein), and when L-NMMA blocked NOS activity in the incubating medium (0.28 +/- 0.05); spermine nonoate (100 microM) abolished the decrease in lipoperoxide level (0.70 +/- 0.02). We conclude that removal of oxygen species produces a decrease in pancreatic NO and NOS levels in STZ-treated rats. Moreover, inhibition of NOS activity produces an increase in SOD activity and a decrease in lipoperoxidation in diabetic pancreatic tissues. Oxidative stress and NO pathway are related and seem to modulate each other in acute STZ-induced diabetic pancreas in the rat.

GABAA and alpha-amino-3-hydroxy-5-methylsoxazole-4-propionate receptors are differentially affected by aging in the rat hippocampus

We have investigated the age-dependent modifications in the expression of eight different subunits of the gamma-aminobutyric acid, type A (GABA(A)) receptor (alpha1, alpha2, alpha3, alpha5, beta2, beta3, gamma2S, and gamma2L) and all four subunits of the alpha-amino-3-hydroxy-5-methylsoxazole-4-propionate (AMPA) receptor (GluR1-4) in the hippocampus of 24-month-old rats. All aged hippocampi displayed a remarkable increase (aged/adult ratio, 3.53 +/- 0.54) in the mRNA levels of the short version of the gamma2 subunit in parallel with a similar increase in the gamma2 subunit protein (aged/adult ratio, 2.90 +/- 0.62). However, this increase was not observed in the mature receptor. On the other hand, the expression of the different alpha subunit mRNAs increased moderately with aging, displaying a heterogeneous pattern. The most frequent modification consisted in an increase in the expression of the alpha1 subunit mRNA (aged/adult ratio, 1.26 +/- 0.18), in parallel with a similar increase on the alpha1 protein (aged/adult ratio, 1. 27 +/- 0.12) and in the alpha1 incorporated to the assembled GABA(A) receptor (tested by immunoprecipitation; aged/adult ratio, = 1.20 +/- 0.10). However, in the same hippocampal samples, no major modifications were observed on the expression of the AMPA receptor subunits. As a whole, these results indicated the existence of an increased expression of the GABA(A) receptor subunits and a preservation of the AMPA receptor at the hippocampal formation. These modifications could reflect the existence of specific deficiencies (neuronal loss and/or deafferentiation) on the GABAergic system in the aged rats.

[Hypothyroidism as a complication of the treatment of hepatitis C with interferon]

Interferon is becoming the most important therapy for chronic hepatitis due to hepatitis C virus. Secondary effects are frequent and sometimes so important to stop the therapy. Autoimmune disorders, specially autoimmune thyroid diseases may occur. We report two out of 69 chronic hepatitis C patients treated with interferon who developed hypothyroidism, that required definitive substitutive therapy.

[Continuous domiciliary oxygen therapy in Zaragoza: a cross-sectional home study]

To assess use of long-term domiciliary oxygen therapy (LDOT) in Saragossa by means of home interviews. We conducted a cross-sectional study of patients undergoing LDOT, interviewing 312 of the 614 patients who used O2 at home in January 1993 (103/100,000 h). Health care workers visited the patients at home and collected all available information related to indications, pattern of use of O2 and complementary tests done. The interviewer also took spirometric readings, SaO2 readings breathing room air and after 30 min breathing O2, and administered a quality of life questionnaire (only to patients with pneumopathies). All patients selected were assessed; 195 (62.5%) suffered from chronic obstructive pulmonary disease (COPD), 33 (10.6%) from asthma, 31 (9.9%) from other pneumopathies, and 53 (17%) from a variety of conditions that were not primarily bronchopulmonary. Thirty-six (11.5%) were active smokers. Only 101 of the 184 patients for whom arterial gasometric readings were available met the criteria for prescribing LDOT. SaO2 without O2 was > or = 92% in 89 (28.5%) patients and > or = 90% in 193 (61.8%). Only 96 (31%) patients reported using O2 more than 15 hours/day and there was a weak inverse relation (p = 0.04) between hours of use and FEV1 in the COPD group. Quality of life for patients with pneumophaties depended entirely on degree of lung function deterioration and was unrelated to use of O2. The rate of use of LDOT Saragossa is one of the highest in Spain. In an estimated 28.5-46% of cases, the indications are inappropriate, mainly due to infrequent use of arterial gas measurement and the prescription of LDOT for patients without COPD. This situation largely explains why patients hardly ever use LDOT on a daily basis.