AB0326 USEFULNESS OF THE INTIMA-MEDIA THICKNESS INDEX BY CAROTID DOPPLER IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS OF HOSPITAL DOCENTE PADRE BILLINI, DOMINICAN REPUBLIC

Background:

Systemic lupus erythematosus (SLE) is a multisistemic autoimmune disease. 1There are studies where the increase in the thickness of the intimate/media average in carotid (IMT) is valued, most have shown increase2. Cardiovascular disease is one of the leading causes of morbidity, especially due to its precocity, which occurs in women during the fertile potential, is associated with a higher prevalence of cardiovascular disease (CVD), due to accelerated atherosclerosis3,4,5. Patients with rheumatic diseases have an increased cardiovascular risk due to systemic inflammation and endothelial dysfunction, which promotes accelerated atherosclerosis2. Values below 0.9mm of IMT are considered normal.

Objectives:

Evaluate the thickness of the intimate/media average in carotid in patients with systemic lupus erythematosus.

Methods:

Prospective, Observational, cross-sectional study. Carotid Doppler was performed on patients in the outpatient clinic with a diagnosis of SLE from November 2019 to 2020 of the rheumatology service of the Hospital Docente Padre Billini and healthy controls. Inclusion criteria: > 18 years old, SLE diagnosis with ACR 2007 classification criteria, carotid Doppler, measurement of IMT. Controls without disease, matched by sex and age. The data was analyzed with SPSS V23.

Results:

116 patients with SLE. 95 patients met inclusion criteria;95 healthy controls were included. 97.8% female. Average disease of 6.23 years. 71. 57% (68) use glucocorticoids, antimalarials 70.52% (67), 38.94% (37) mofetil mycophenolate, 20% (19) methotrexate, 11. 57% (11) rituximab, 5.26% (5) azathioprine, 1.05% (1) cyclosporine, 1.05% (1) cyclophosphamide and 0.86% (1) tacrolimus. Dyslipidemia (63.1%) (73), obesity 34.7% (33), high blood pressure 23.1% (22), diabetes 3.44% (4), smokers 0% (0). The carotid doppler with SLE showed 17.89% (17) atheromatous plates, 29.4% (5) calcified plates, Carotid Doppler in healthy controls showed 20% (19) atheromatous plates, 36.84% (7) calcified plates. The activity rate using SLEDAI showed 68.96% (80) without activity, 13.79% (16) low, 11.20% (13) moderate, 6.03% (7) high activity. 78% (75) patients with SLE had increased IMT mean (SD) 2.15mm (0.99). About control 71.57% (68) had an increase of IMT, mean (SD) 1.27mm (1.07) (p-0.046).

Conclusion:

Our study found that most patients with SLE had IMT increase. The activity ratio of SLE showed that the vast majority of our patients are in low activity. Alterations in IMT were associated with low SLEDAI and glucocorticoid use. There was no significant difference in the intima-media carotid thickness index with respect to the control group. We suggest the realization of Doppler in patients with SLE despite being in low activity for evaluation and monitoring of cardiovascular risk.

References:

[1]Hernández Muñiz, Y, Guibert Toledano, Z. and Reyes Llerena, G., 2015. Correlation of C Reactive Protein Figures and Atherosclerosis in Patients with Systemic Lupus Erythematosus.

[2]Saldarriaga Rivera, L., Ventura Ríos, L., Hernández Díaz, C. and Pineda Villaseñor, C., 2016. Measurement of the thickness of the intimate-half carotid: utility and ultrasound diagnosis of subcline atherosclerosis in rheumatic diseases. Literature review. Rev Col Reum, 23(2), pp.92-101.

[3]Telles, R., Lanna, C., Ferreira, G., Souza, A., Navarro, T. and Ribeiro, A., 2008. Carotid atherosclerotic alterations in systemic lupus erythematosus patients treated at a Brazilian university setting. Lupus, 17(2), pp.105-113.

[4]Nienhuis, H., by Leeuw, K., Bijzet, J., van Doormaal, J., van Roon, A., Smit, A., Graaff, R., Kallenberg, C. and Bijl, M., 2010. Small artery elasticity is decreased in patients with systemic lupus erythematosus without increased intima media thickness. Arthritis Research & Therapy, 12(5), p.R181.

[5]Frerix et al. Arthritis Research & Therapy 2014, 16: R54

Disclosure of Interests:

None declared

AB0325 FREQUENCY OF ATHEROMATOUS PLAQUES IN CAROTID ARTERIES BY DOPPLER IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS, SANTO DOMINGO, DOMINICAN REPUBLIC

Background:

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease. 1 Atherosclerosis is considered an alteration of the arteries by the abnormal deposit of lipids and fibrous tissue. 2 Cardiovascular disease is one of the leading causes of morbidity and mortality, especially due to its precocity, which occurs in women during childbearing age, is associated with a higher prevalence of cardiovascular disease (CVD), due to accelerated atherosclerosis3,4,5. Patients with rheumatic diseases have an increased cardiovascular risk due to systemic inflammation and endothelial dysfunction, which promotes accelerated atherosclerosis2.

Objectives:

Evaluate the frequency of atheromatous plaques in patients with systemic lupus erythematosus.

Methods:

Observational, prospective, cross-sectional study. Carotid Doppler was performed on patients with SLE from the external consultation of the rheumatology service from November 2019 to 2020. Inclusion criteria: > 18 years old, diagnosis SLE with the classification criteria ACR 2007, realization of Doppler. Controls: no disease, equated by age and sex. The data was analyzed with SPSS V23.

Results:

116 patients met inclusion criteria, including 116 female controls. Mean sick time was 6.23 years. 14.65% (17) had atheromaus plates, 29.4% calcified plates (5). 34.7% Dyslipidemia (63.1%) (73), obesity 34.7% (33), high blood pressure 23.1% (22), diabetes 3.44% (4), smokers 0% (0). The activity rate using SLEDAI showed 68.96% (80) without activity, 13.79% (16) low, 11.20% (13) moderate, 6.03% (7) high activity. About control group (116), 19.82% (23) showed atheromatous plates, 39.13% (9) calcified plates.

Conclusion:

Our study shows that less than a quarter of patients have atheromatous plaques in the carotid Doppler. In relation to LES activity, the vast majority are in low activity. We suggest the realization of Carotid Doppler in patients with low activity SLE for evaluation and monitoring of cardiovascular risk. Our study showed that there is no increased risk of atheroma plaque formation in SLE patients, compared to the general population.

References:

[1]Hernández Muñiz, Y., Guibert Toledano, Z. and Reyes Llerena, G., 2015. Correlation of C Reactive Protein Figures and Atherosclerosis In Patients with Systemic Lupus Erythematosus.

[2]Saldarriaga Rivera, L., Ventura Ríos, L., Hernández Díaz, C. and Pineda Villaseñor, C., 2016. Measurement of the thickness of the intimate-half carotid: utility and ultrasound diagnosis of subcline atherosclerosis in rheumatic diseases. Literature review. Rev Col Reum, 23(2), pp.92-101.

[3]Telles, R., Lanna, C., Ferreira, G., Souza, A., Navarro, T. and Ribeiro, A., 2008. Carotid atherosclerotic alterations in systemic lupus erythematosus patients treated at a Brazilian university setting. Lupus, 17(2), pp.105-113.

[4]Nienhuis, H., by Leeuw, K., Bijzet, J., van Doormaal, J., van Roon, A., Smit, A., Graaff, R., Kallenberg, C. and Bijl, M., 2010. Small artery elasticity is decreased in patients with systemic lupus erythematosus without increased intima media thickness. Arthritis Research & Therapy, 12(5), p.R181.

[5]Frerix et al. Arthritis Research & Therapy 2014, 16: R54.

[6]Marta, M., Joan T., Stefano B., Chapt 2 - Assessment of Disease Activity in Systemic Lupus Erythematosus, Systemic Lupus Erythematosus, Mosby, 2007.

Disclosure of Interests:

None declared

POS0550 EVALUATION OF THE INTIMA-MEDIA THICKNESS INDEX BY CAROTID DOPPLER IN PATIENTS WITH RHEUMATOID ARTHRITIS AT HOSPITAL DOCENTE PADRE BILLINI, DOMINICAN REPUBLIC

Background:

Rheumatoid arthritis (RA) is an autoimmune disease systemic, affects 0.5 - 1% of the world population, predominantly female. (1) Carotid Doppler is used to detect endothelial dysfunction by measuring intima-media thickening, flow velocities, subclinical atherosclerosis markers, and vascular tone.(2,3) Measurement of carotid intima-media thickness (cIMT) is useful in assessing cerebrovascular disease and cardiovascular risk in patients with rheumatoid arthritis (4) Intima-media thickness value> 0.9mm and presence of plaques Atheromatous cells in the carotid artery are predictive of increased cardiovascular risk and silent heart disease. (5.6)

Objectives:

To evaluate the carotid intima-media thickness in patients with rheumatoid arthritis

Methods:

A prospective, observational, cross-sectional study. Carotid Doppler was performed on outpatient patients with a diagnosis of rheumatoid arthritis from November 2019 to 2020 of the rheumatology service of the Hospital Docente Padre Billini and healthy controls. Inclusion criteria:> 18 years, diagnosis of RA according to ACR / EULAR 2010 classification criteria, carotid Doppler with measurement of the carotid intima-media thickness. Controls without disease, matched by sex and age. The data were analyzed with SPSS V23.

Results:

Of 251 patients with a diagnosis of RA, 100 met criteria inclusion, 96.2% female, 100 healthy controls were included. Average evolution of the disease 7.5 years, 88%(88) Positive rheumatoid factor, 33% (33) Positive anti-CCP. 82% (82) concomitant scDMARD, 70% (70) bDMARD, 18% (18) ctDMARD. 53% (53) Dyslipidemia, 23% (23) obesity, 10% (10) hyperglycemia, 8% (8) smokers. DAS28 showed 57% (57) low activity, 20% (20) moderate activity, 15% (15) remission, 8% (8) high activity. Carotid Doppler in patients with RA showed 32% (32) atheromatous plaques, 18.75% (6) calcified plaques, 1.44% (1) stenosis bilateral carotid. C-reactive protein and erythrocyte sedimentation rate high 35% (35) / 58% (58) respectively. Carotid Doppler in healthy controls revealed 17% (17) atheromatous plaques, 47.05% (8) calcified plaques. 69% (69) of RA patients had increased cIMT, mean (SD) cIMT 3.82mm (1.11), controls 58% (58) increase in cIMT, Mean (SD) 3.12mm (0.93) (p = 0.0435).

Conclusion:

Our study showed that 69% of patients with Arthritis Rheumatoid featured increased intima-media thickness associated with low DAS28, we recommend assessing cardiovascular risk using carotid Doppler in patients with low to moderate activity. It was observed that in patients with RA and healthy controls more than half present increased carotid intima-media thickness.

References:

[1]JAMA. 2018;320(13):1360-1372.

[2]Villa-Forte, B.F. Mandell / Rev Esp Cardiol. 2011;64(9):809–817.

[3]Meune, C., Touzé, E., Trinquart, L., Allanore, Y. Trends in cardiovascular mortality in patients with rheumatoid arthritis over 50 years: A systematic review and meta-analysis of cohort studies. Rheumatology 2009; 48 (10): 1309-13.

[4]Choi, HK., Rho, Y-H., Zhu, Y., Cea-Soriano, L., Aviña-Zubieta, JA., Zhang, Y. The risk of pulmonary embolism and deep vein thrombosis in rheumatoid arthritis: A UK population-based outpatient cohort study. Ann Rheum Dis. 2013; 72 (7): 1182-7.

[5]Gkaliagkousi, E., Gavriilaki, E., Doumas, M., Petidis, K., Aslanidis, S., Stella, D. Cardiovascular risk in rheumatoid arthritis: Pathogenesis, diagnosis, and management. J Clin Rheumatol Pract Rep Rheum Musculoskelet Dis. 2012; 18 (8): 422-30.

[6]Corrales, A., González-Juanatey, C., Peiró, ME., Blanco, R., Llorca, J., González-Gay, MA. Carotid ultrasound is useful for the cardiovascular risk stratification of patients with rheumatoid arthritis: Results of a population-based study. Ann Rheum Dis. 2013.

Disclosure of Interests:

None declared

AB0635 EVALUATION OF THE INTIMA-MEDIA THICKNESS INDEX BY CAROTID DOPPLER IN PATIENTS WITH MONOSODIUM URATE DEPOSITION ARTHRITIS OF THE HOSPITAL DOCENTE PADRE BILLINI, DOMINICAN REPUBLIC

Background:

Hyperuricemia and gout are risk factors for atherosclerosis subclinical and cardiovascular complications. (1) However, it is still debated whether uric acid is an independent predictor of cardiovascular risk. (2) Vascular Doppler and in particular the measurement of the intima-media thickness and the detection of plaques are useful in the evaluation of cerebrovascular disease and cardiovascular risk. (3) An intima-media thickness greater than 0.9 mm and / or the presence of atheromatous plaques in the carotid are predictive of high cardiovascular risk and silent heart disease. (4) Gouty arthritis has been associated with alteration of the carotid intima media thickness (cIMT) and subclinical atherosclerosis. Cukurova et al studied patients with gout, finding an increase in cIMT compared to patients with asymptomatic hyperuricemia. (5)

Objectives:

Assess the carotid intima-media thickness in patients with monosodium urate deposits arthritis

Methods:

Prospective, observational, cross-sectional study. Carotid Doppler was performed on patients in the outpatient clinic with a diagnosis of gout from November 2019 to 2020 of the rheumatology service of the Hospital Docente Padre Billini and healthy controls. Inclusion criteria, patients> 18 years, diagnosis of monosodium urate deposits arthritis according to the ACR / EULAR 2015 classification criteria, carotid Doppler, measurement of the cIMT. Controls without disease, matched by sex and age. The data was analyzed with SPSS V23 for Windows 10.

Results:

Of 37 patients with a diagnosis of arthritis due to deposition of monosodium urate crystals, (34) met inclusion criteria, 100% male, 34 healthy controls. Average of 61.5 years. Average of the disease 8.2 years. Distribution 61% (21) intercritical gout, 32% (11) chronic tophaceous gout, 0.5% (2) acute gouty arthritis. Comorbidities 67% (23) dyslipidemia, 35% (12) hyperglycemia. 26% (9) presented arterial hypertension. 20% (7) have diabetes mellitus. 58% (20) are alcohol drinkers, 11% (4) smokers. Mean uric acid 8.6 mg / dl at Doppler, 52% (18) elevated serum creatinine. Carotid Doppler in patients with gout showed a 55% (19) increase in the cIMT > 0.9mm, with a mean of 2.03mm (1.95 SD). Carotid Doppler in healthy controls 17% (6) increased cIMT, mean of 1.8mm (2.2 SD) (P = 0.040). Patients with gout had 29% (10) atheromatous plaques, 17% (6) calcified plaques versus 14% (5) atheromatous plaques, 8% (3) calcified in healthy controls.

Conclusion:

Our study showed that half of the patients with gout had increased cIMT compared to a third of the healthy controls. The presence of atheromatous and calcified plaques was mainly associated with dyslipidemia, so we can conclude that the evaluation of the intima-media thickness by carotid Doppler allows it to be a predictor of cardiovascular disease in patients with gout.

References:

[1]Choi HK, Curhan G (2007) Independent impact of gout on mortality and risk for coronary heart disease. Circulation 116:894–900

[2]Feig DI, Kang DH, Johnson RJ (2008) Uric acid and cardiovascular risk. N Engl J Med 359:1811–1821

[3]Choi, HK. Rho, Y-H., Zhu, Y., Cea-Soriano, L., Aviña-Zubieta, JA. Zhang, Y. The risk of pulmonary embolism and deep vein thrombosis in rheumatoid arthritis: A UK population-based outpatient cohort study. Ann Rheum Dis. 2013; 72 (7): 1182-7

[4]Gkaliagkousi, E., Gavriilaki, E., Doumas, M., Petidis, K., Aslanidis, S., Stella, D. Cardiovascular risk in rheumatoid arthritis: Pathogenesis, diagnosis, and management. J ClinRheumatolPract Rep Rheum Musculoskelet Dis. 2012; 18 (8): 422-30

[5]Cukurova S, Pamuk ÖN, Ünlü E, Pamuk GE, C¸ akir N. Subclinical atherosclerosis in gouty arthritis patients: a comparative study. Rheumatol Int. 2012; 32(6):1769–73.

Disclosure of Interests:

None declared.

Somatic innervation contributes to the release of bulbourethral gland secretion in male rats

BACKGROUND

In male rats, the bulbourethral glands (Bu-Gs) are the unique accessory sexual glands surrounded by striated musculature. However, until now the role of this musculature was unknown.

OBJECTIVES

(i) To characterize the Bu-Gs striated muscular layer in male rats and determine its innervation and response to genital stimulation. (ii) To reveal the role of the Bu-Gs striated musculature in the release of glandular secretion. (iii) To elucidate the effect of bilateral ablation of the Bu-Gs on copulatory behavior and seminal fluid characteristics.

MATERIALS AND METHODS

Adult Wistar male rats were allocated in three experiments: in Experiment 1, the Bu-Gs striated musculature, innervation and reflex activity were determined by gross anatomy and histological and electrophysiological techniques; electromyographic activity of the Bu-Gs striated musculature was evoked with genital stimulation. In Experiment 2, Bu-Gs were analyzed after copulatory behavior of intact or animals with unilateral transected motor branch of the sacral plexus (MBSP). In Experiment 3, copulatory behavior and spermatobioscopy of males with bilateral ablation of the Bu-Gs or sham surgery were analyzed.

RESULTS

The Bu-Gs striated fibers discharged in response to mechanostimulation of the prepuce, glans, and penile-urethra. Innervation of the Bu-Gs striated musculature originated from the MBSP; this nerve also innervates striated penile muscles. Unilateral transection of the MBSP significantly decreased the secretion from the ipsilateral Bu-G to the nerve transection. Bilateral ablation of Bu-Gs did not affect seminal plug formation but decreased semen viscosity.

DISCUSSION AND CONCLUSION

The Bu-Gs striated musculature contributes to expel glandular secretion during sexual intercourse. The somatic control of Bu-Gs secretion is additional to the reported autonomic innervation supplied by the cavernosus nerve, which may underlie the synthesis of secretion as well as contraction of Bu-Gs smooth muscle.

Partitioning heritability analysis reveals a shared genetic basis of brain anatomy and schizophrenia

Schizophrenia is a devastating neurodevelopmental disorder with a complex genetic etiology. Widespread cortical gray matter loss has been observed in patients and prodromal samples. However, it remains unresolved whether schizophrenia-associated cortical structure variations arise due to disease etiology or secondary to the illness. Here we address this question using a partitioning-based heritability analysis of genome-wide single-nucleotide polymorphism (SNP) and neuroimaging data from 1750 healthy individuals. We find that schizophrenia-associated genetic variants explain a significantly enriched proportion of trait heritability in eight brain phenotypes (false discovery rate=10%). In particular, intracranial volume and left superior frontal gyrus thickness exhibit significant and robust associations with schizophrenia genetic risk under varying SNP selection conditions. Cross-disorder comparison suggests that the neurogenetic architecture of schizophrenia-associated brain regions is, at least in part, shared with other psychiatric disorders. Our study highlights key neuroanatomical correlates of schizophrenia genetic risk in the general population. These may provide fundamental insights into the complex pathophysiology of the illness, and a potential link to neurocognitive deficits shaping the disorder.

Neuroanatomic and behavioral correlates of urinary dysfunction induced by vaginal distension in rats

The aim of the present study was to use a model of simulated human childbirth in rats to determine the damage to genitourinary structures and behavioral signs of urinary dysfunction induced by vaginal distension (VD) in female rats. In experiment 1, the length of the genitourinary tract and the nerves associated with it were measured immediately after simulated human delivery induced by VD or sham (SH) procedures. Electroneurograms of the dorsal nerve of the clitoris (DNC) were also recorded. In experiment 2, histological characteristics of the bladder and major pelvic ganglion of VD and SH rats were evaluated. In experiment 3, urinary parameters were determined in conscious animals during 6 h of dark and 6 h of light before and 3 days after VD or SH procedures. VD significantly increased distal vagina width (P < 0.001) and the length of the motor branch of the sacral plexus (P < 0.05), DNC (P < 0.05), and vesical nerves (P < 0.01) and decreased DNC frequency and amplitude of firing. VD occluded the pelvic urethra, inducing urinary retention, hematomas in the bladder, and thinness of the epithelial (P < 0.05) and detrusor (P < 0.01) layers of the bladder. Major pelvic ganglion parameters were not modified after VD. Rats dripped urine in unusual places to void, without the stereotyped behavior of micturition after VD. The neuroanatomic injuries after VD occur alongside behavioral signs of urinary incontinence as determined by a new behavioral tool for assessing micturition in conscious animals.

BioAssay Research Database (BARD): chemical biology and probe-development enabled by structured metadata and result types

BARD, the BioAssay Research Database (https://bard.nih.gov/) is a public database and suite of tools developed to provide access to bioassay data produced by the NIH Molecular Libraries Program (MLP). Data from 631 MLP projects were migrated to a new structured vocabulary designed to capture bioassay data in a formalized manner, with particular emphasis placed on the description of assay protocols. New data can be submitted to BARD with a user-friendly set of tools that assist in the creation of appropriately formatted datasets and assay definitions. Data published through the BARD application program interface (API) can be accessed by researchers using web-based query tools or a desktop client. Third-party developers wishing to create new tools can use the API to produce stand-alone tools or new plug-ins that can be integrated into BARD. The entire BARD suite of tools therefore supports three classes of researcher: those who wish to publish data, those who wish to mine data for testable hypotheses, and those in the developer community who wish to build tools that leverage this carefully curated chemical biology resource.

Histopathological and Behavioral Characterization of a Novel Cervical Spinal Cord Displacement Contusion Injury in the Rat

Cervical contusive trauma accounts for the majority, of human spinal cord injury (SCI), yet experimental use of cervical contusion injury models has been limited. Considering that (1) the different ways of injuring the spinal cord (compression, contusion, and transection) induce very different processes of tissue damage and (2) the architecture of the spinal cord is not uniform, it is important to use a model that is more clinically applicable to human SCI. Therefore, in the current study we have developed a rat model of contusive, cervical SCI using the Electromagnetic Spinal Cord Injury Device (ESCID) developed at Ohio State University (OSU) to induce injury by spinal cord displacement. We used the device to perform mild, moderate and severe injuries (0.80, 0.95, and 1.1 mm displacements, respectively) with a single, brief displacement of <20 msec upon the exposed dorsal surface of the C5 cervical spinal cord of female (180-200 g) Fischer rats. Characterization of the model involved the analysis of the temporal histopathological progression of the injury over 9 weeks using histochemical stains to analyze white and gray mater integrity and immunohistochemistry to examine cellular changes and physiological responses within the injured spinal cord. Accompanying the histological analysis was a comprehensive determination of the behavioral functionality of the animals using a battery of motor tests. Characterization of this novel model is presented to enable and encourage its future use in the design and experimental testing of therapeutic strategies that may be used for human SCI.

Purification and conformational properties of a human interferon alpha2b produced in Escherichia coli

Recombinant human interferon alpha2b was expressed intracellularly in Escherichia coli as insoluble aggregates using a new expression vector, and was purified to homogeneity using essentially two-step chromatographic procedures, i.e. immobilized metal-ion-affinity chromatography and reversed-phase HPLC. The established purification process is highly reproducible and leads to a total recovery of approx. 12% with a specific biological activity of higher than 1x10(8) i.u./mg of protein, which is comparable with the international requirement for interferon alpha2b. For purified protein we report conformational stability as a function of pH and temperature using differential scanning calorimetry and CD. Thermal unfolding as a function of pH showed only one endotherm at a temperature higher than 45 degrees C, and was reversible at pH 2-3.75 and irreversible at pH 4-10. At pH 7.0, the most stable condition, the conformational stability depends on protein concentration and ionic strength. The highly helical secondary structure is very conserved over the whole pH range studied, including at high temperatures.

Temporal and behavioral patterning of parturition in rabbits and rats

Although the rabbit (Oryctolagus cuniculus) continues to play an important role in the study of parturitional processes, a detailed behavioral description of birth in this species, necessary for accurately assessing the effects of experimental manipulation, is lacking. It is the aim of this report to provide such a description and to compare it with corresponding behavior in the better-studied rat. Ten pregnant chinchilla-breed rabbits and 10 pregnant Wistar rats were placed in glass-bottomed observation cages 2 days before term, and their behavior recorded on closed-circuit video, viewing the animals from below. All aspects of parturition were accomplished much faster in rabbits than rats; latency to birth of first pup, rate of delivery, duration of vaginal retention, time spent by mothers eating placentas, and in licking and nursing pups. In contrast to rat pups, rabbits were usually born separated from the placenta and already free from membranes. They were much more active, and well able to cast off any remaining membranes, suckle, and survive, whether directly attended to by the mother or not. We conclude that the tight temporal organization of events in the rabbit provides an unusually sensitive assay for investigating mechanisms underlying mammalian parturition.

The sensory but not muscular pelvic nerve branch is necessary for parturition in the rat

In the rat the pelvic nerve consists of a viscerocutaneous (sensory) branch which receives information from pelvic viscera and the midline perineal region, and a somatomotor (muscular) branch which innervates the ilio- and pubococcygeous muscles. To investigate the contribution of these branches to the parturition process, the length of gestation and course of delivery were closely monitored in 43 pregnant, Wistar-strain rats randomly assigned to five groups: untreated control animals, animals in which the somatomotor branch of the pelvic nerve was bilaterally sectioned on Day 14 of gestation, animals in which the viscerocutaneous branch of the pelvic nerve was bilaterally sectioned on Day 14 of gestation, animals treated similarly to the previous group but with young delivered by C-section at term, and sham-operated controls. Sectioning the viscerocutaneous branch seriously disrupted parturition and resulted in major dystocia and a high percentage of stillbirths in all females. In contrast, sectioning the somatomotor branch had no apparent effect on parturition and no significant differences were found between females of this group and sham or control dams on any of the measures recorded. It is concluded that the viscerocutaneous branch of the pelvic nerve is vital for the normal course of parturition in the rat but that the somatomotor branch plays little role, if any.

PCR detection of human papillomavirus: comparison between MY09/MY11 and GP5+/GP6+ primer systems

Human papillomavirus (HPV) is an etiologic agent of cervical cancer and is the most common sexually transmitted disease in women. PCR amplification of HPV genomes is the most sensitive method for the detection of cervicovaginal HPV. We have compared the two most commonly used PCR primer sets, MY09/MY11 (MY-PCR) and GP5+/GP6+ (GP+-PCR), for the detection of HPV DNA in cervicovaginal lavage samples from 208 women. Oligonucleotide probes for 39 different HPV types were used. Both primer sets amplified a wide spectrum of HPV genotypes and detected similar overall prevalences of 45% (94 of 208) and 43% (89 of 208), respectively. The MY-PCR system detected 27 of 30 (90%) samples with multiple HPV types, whereas the GP+-PCR system detected 14 of 30 (47%) samples with multiple HPV types. Differences in the detection of HPV types 35, 53, and 61 were noted between the two primer systems. Serial dilution of plasmid templates indicated a 3-log decrease in the amplification of HPV type 35 by MY-PCR and HPV types 53 and 61 by GP+-PCR. These results indicate that although the MY-PCR and GP+-PCR identified nearly equivalent prevalences of HPV in a set of clinical samples, differences in the detection of specific types and infections with multiple types were found. Differences in the sensitivities and characteristics of the PCR systems for the detection of HPV within clinical samples should be considered when comparing data between studies and/or in designing new studies or clinical trials.

Changes in pain threshold during the reproductive cycle of the female rat

Responsiveness to pain was determined in female rats across the whole reproductive cycle using the tail-flick test. When tested immediately after mating, pain thresholds were unaltered, whereas 10 min later animals typically demonstrated hyperalgesia (Experiment 1). They also demonstrated hyperalgesia during most of pregnancy, and had significantly lower pain thresholds than the unmated controls except for the 24 h before parturition, when a sudden increase in tail-flick latencies was recorded (Experiment 2). Pain thresholds were also significantly lower throughout the nursing period but increased significantly when dams were separated from their litters for 6 h, and returned to premating baseline values within 24 h of weaning (Experiment 3). These findings confirm and extend earlier reports that female reproductive state may significantly modify responsiveness to noxious stimuli, and it is suggested that differences between the results of this and previous studies may be at least partly explained by the relatively stress-free test procedure adopted here.

Analysis of short novel human papillomavirus sequences

Consensus primer mediated PCR protocols have the potential to amplify previously uncharacterized human papillomavirus (HPV) genotypes. In a study on 500 cervicovaginal samples, we amplified four sequences (L1AE 1 to L1AE 4) that failed to hybridize to any of the available HPV type-specific oligonucleotide probes. Nucleotide sequencing revealed that the sequences were derived from the L1 region of hitherto unsequenced genotypes. Comparison of phylogenetic trees based on the amplified L1 sequences with E6-derived phylogenetic trees resulted in the identification of L1AE 1 and L1AE 2 as putative novel HPV PCR genotypes. L1AE 1 was related to HPV 39, whereas L1AE 2 was related to HPV 51. The L1AE 3 and L1AE 4 sequences occupied L1-phylogenetic branches equivalent to the positions of HPV 66 and HPV 61, respectively, in an E6-phylogenetic tree.

Assessing pain threshold in the rat: changes with estrus and time of day

Pain threshold was determined in female rats using the tail flick test. Latency to respond depended on the locus of the tail heated, with the most distal sites resulting in the shortest response times (Experiment 1). Tail flick latency also varied according to the time of day, with shorter response times recorded around the middle of the dark phase than near its beginning or after its end. This was the case for intact, for ovariectomized, and for ovariectomized, estradiol-treated rats (Experiment 2). However, response times also varied across the estrous cycle, with significantly shorter latencies recorded during estrus and metestrus. Ovariectomy abolished these fluctuations, and whereas administration of estradiol increased response times, progesterone had little effect (Experiment 3). These results suggest that site of tail heating, time of day, and presence of ovarian hormones can influence tail flick latency independently, thus demonstrating the complexity of the mechanisms that may contribute to pain threshold even within the same paradigm.