[Evaluation of the Knowledge of Women of Childbearing Age with Epilepsy about the Impact of Their Disease in Contraception, Pregnancy and Breastfeeding: A Multicenter Cross-Sectional Study]

INTRODUCTION

The interaction of antiseizure medication with contraceptives, its potential teratogenicity and implications in pregnancy and breastfeeding are aspects to consider in the neurological care of women with epilepsy of childbearing age. To ensure the commitment in therapeutic decisions and the appropriate planning of maternity, it is essential that women are informed about the implications of their disease in these domains. The main aim of this study was to assess the knowledge of women of childbearing age with epilepsy concerning the impact of epilepsy in contraception, pregnancy and breastfeeding. As secondary aims we defined (1) the demographic, clinical and therapeutic characterization of this group of patients, (2) the identification of variables that correlated with the level of knowledge of women with epilepsy, and (3) the identification of preferential methods to acquire new knowledge about epilepsy.

MATERIAL AND METHODS

The study was observational, cross-sectional and multicentric, and was carried out in five hospitals of the Lisbon metropolitan area. After identifying all women of childbearing age with epilepsy followed in the epilepsy clinic of each center, we applied an electronic questionnaire based on a non-systematic review of the literature.

RESULTS

One hundred and fourteen participants were validated, with a median age of 33 years. Half of the participants were on monotherapy, and the majority had no seizures in the last six months. We identified important gaps in the participants' knowledge. Sections about complications and administration of antiseizure medication during pregnancy were the ones with the worst results. None of the clinical and demographic variables correlated with the final questionnaire score. Having had a previous pregnancy and the desire to breastfeed in a future pregnancy were positively correlated with the performance in breastfeeding section. Face-to-face discussion during medical outpatient visits was selected as the preferential method to learn about epilepsy, and the internet and social media were the least preferred ones.

CONCLUSION

The knowledge of women of childbearing age with epilepsy in the Lisbon metropolitan area concerning the impact of epilepsy in contraception, pregnancy and breastfeeding seems to have significant gaps. Medical teams should consider engaging in patient education particularly during outpatient clinics.

P766 Elegibility for CLOSE and REDUCE trials of real world patients with Transient Ischemic Attack (TIA) or Acute Ischemic Stroke (AIS) and Patent Foramen Ovale (PFO)

Introduction

In the last decade there has been an intense discussion in which therapeutic option is most suitable for patients with TIA or cryptogenic AIS and a PFO. Recently two randomised studies (CLOSE and REDUCE) have been published tackling this question. Both have showed preference in lower recurrence rates in the group assigned for PFO closure. The eligibility criteria of these types of studies frequently are very restricted, becoming difficult to ascertain the best therapeutic option for a large number of patients.

Goal

Analyse a real world cohort of patients with TIA or cryptogenic AIS with PFO and identify the eligibility of these patients for the inclusion in the CLOSE and REDUCE trials.

Methods

We made a retrospective observational analysis of a cohort of patients discussed in a multidisciplinary meeting (Cardiology and Neurology departments) of our Hospital in which is made the decision of PFO closure vs conservative management between November 2017 and November 2018. We included all the patients with probable TIA or AIS and PFO. Demographic, clinical, image and therapeutic data was registered. The inclusion and exclusion criteria used in CLOSE and REDUCE trial were applied.

Results

25 patients were analysed, 56.0% (n = 14) were male. Median age of 47 years. Median RoPE score 7. The commonest cardiovascular risk factors were hypertension (36.0%, n = 9) and smoking (28.0%, n = 7). Eight patients met criteria for cortical cryptogenic AIS, three had lacunar strokes, two had TIA with findings in cerebral imaging and twelve presented with TIA without findings in cerebral imaging. Transesophagic echocardiography was performed in 92.0% (n = 23) of patients, transthoracic echocardiography with bubble study was performed in two cases. At the time of data collection, six patients were waiting completion of the workup. PFO closure was performed in three cases. Closure was proposed in other two. When applying the eligibility criteria of CLOSE and REDUCE the main reasons for exclusion in the REDUCE trial were TIA without cerebral imaging (48.0%, n = 12), incomplete antiphospholipid antibody syndrome screening (36.0%, n = 9) and age greater than 59 years (28.0%, n = 7). The main reasons for exclusion in the CLOSE trial were TIA without cerebral imaging (48.0%, n = 12), age greater than 60 years (28%, n = 7) and failing to meet the designated echocardiography criteria (20.0%, n = 5).

Conclusion

2 real world patients met eligibility criteria for the REDUCE trial and 3 for CLOSE. The main reason for exclusion in both REDUCE and CLOSE was TIA without cerebral imaging (48.0% n = 12). Older patients, and patients with a prothrombotic condition were also excluded. Multidisciplinary meetings are essential to ascertain the most beneficial therapeutic option for these patients. It is our believe that the management of risk factors should be similar in a TIA and a AIS and also that the presence of a prothrombotic condition should favor the closure of PFO.

Pressure ulcers or moisture lesions: the theatre perspective

Pressure ulcers continue to be a cause for concern in the healthcare industry (IHI 2015). Unfortunately older patients are at a greater risk of developing pressure ulcers (Kottner et al 2013); moisture lesions and the presence of other comorbidities could have long term effects on the patient's health and recovery.

Biomechanical evaluation of proximal tibia behaviour with the use of femoral stems in revision TKA: an in vitro and finite element analysis

BACKGROUND

Recognized failure mechanisms after revision total knee arthroplasty include failure of fixation, instability and loosening. Thus, extended stems have been used to improve fixation and stability. In clinical cases where the stem is only applied in the femur, a question concerning the structural aspect of tibia may arise: Does a stemmed femur changes the structural behaviour of proximal tibia? It seems, that question has not yet been fully answered and the use of stems in the opposite bone structure requires further analysis.

METHODS

Proximal cortex strains were measured with tri-axial strain gauges in synthetic tibias for three different types of implanted femurs, with two constrained implants. To assess the strains at the cancellous bone under the tibial tray, it was considered a closest physiological load condition with the use of finite element models.

FINDINGS

No significant differences of the mean of the tibial cortex strains for the stemmed femur relatively to the stemless femur were observed. The R(2) and slopes values of the linear regressions between experimental and finite element strains were close to one indicating good correlations. The strain behaviour of cancellous bone under the tibial tray is not completely immune to the use of femoral stem extensions. However, the level of this alteration is relatively small when compared with the strain magnitudes.

INTERPRETATION

The main insight given by the present study could probably lie in the fact that the use of femoral stems does not contribute to an increase of the risk of failure of the tibia.

Maternal and newborn-care practices during pregnancy, childbirth, and the postnatal period: a comparison in three rural districts in Bangladesh

The aim of this study was to examine the prevalence of maternal and newborn-care practices among women reporting a birth in the previous year in three districts in different divisions of Bangladesh. In 2003, 6,785 women, who had delivered a newborn infant in the previous year, across three districts in Bangladesh, were interviewed. Overall, less than half of the women received any antenatal care, and 11% received a minimum of four check-ups. Only 18% took iron tablets for at least four months during pregnancy. Over 90% of the 6,785 deliveries took place at home, and only 11% were attended either by a doctor or by a nurse. The mothers reported three key hygienic practices in 54% of deliveries: attendants washing their hands with soap and boiling cord-tie and blade for cutting the cord. Forty-four percent of the 6,785 infants were bathed immediately after delivery, and 42% were given colostrum as their first food. The results suggest that maternal and newborn-care remains a cause of concern in rural Bangladesh. Short-term policies to promote healthy behaviour in the home are needed, in addition to the long-term goal of skilled birth attendance.

In-use barrier integrity of gloves: latex and nitrile superior to vinyl

BACKGROUND

Although gloves manufactured with different materials have comparable barrier properties when removed directly from the box and tested, their actual on-the-job barrier performance may be extremely different. Although effective in static, pre-use conditions, barrier properties may be compromised once challenged by the rigorous hand and finger movements associated with many health care procedures. Gloves are meant to act as barriers, protecting persons by reducing the risk of exposure to bloodborne pathogens. Ineffective barriers or barriers that are easily breached during risk-associated procedures have the potential to place health care professionals at risk. Multiple studies attesting to the barrier attributes of vinyl and latex gloves during varied controlled clinical situations are available. Studies are available that address the permeation characteristics of nitrile, but no studies document the effectiveness of nitrile as a barrier to bloodborne pathogens or compare the barrier effectiveness of nitrile to gloves made of other materials during simulated use or clinical situations.

OBJECTIVE

This study was undertaken to compare the barrier integrity of latex, vinyl, and nitrile gloves during controlled, simulated clinical use conditions that were specifically designed to mimic patient care activities. This study compares the performance of gloves made of natural rubber latex, long considered the gold standard; polyvinyl chloride (vinyl), a synthetic copolymer; and nitrile (acrylonitrile butadiene), a recently available synthetic for use in the health care environment.

METHODS

A total of 2000 gloves (800 latex gloves, 800 vinyl gloves, and 400 nitrile gloves) were evaluated for baseline determinations in unused gloves and for failure rates after specific simulated use conditions. Potential bias was avoided through strict control of all actions and manipulations. Gloves were graded on a pass or fail system for leaks as defined by American Society for Testing and Materials D5151, Standard Test Method for Detection of Holes in Medical Gloves. To more fully characterize the gloves evaluated, individual products were also tested for physical dimensions (finger and palm thickness), powder levels, total protein (Modified Lowry), and antigenic protein (Latex ELISA [enzyme-linked immunosorbent assay] for Antigenic Proteins).

RESULTS

With the exception of one vinyl glove brand with a 12% failure rate, no significant differences in failure rates were detected among the 3 types of gloves when tested directly out of the box with no manipulation. However, after manipulation intended to simulate in-use conditions, vinyl gloves failed 12% to 61% of the time. Latex and nitrile performed significantly better, with failure rates of only 0% to 4% and 1% to 3%, respectively. All latex gloves, with one exception, tested at less than 50 microg/g of total water extractable protein. The antigenic protein levels, with one exception, tested from less than 0.2 microg/g to 5.5 microg/g. The one latex product that fell outside these values had 154 microg/g of total protein and 105.7 microg/g of antigenic protein.

CONCLUSIONS

This study indicates that the latex and nitrile gloves evaluated were comparable in terms of barrier performance characteristics both unused and during manipulations mimicking patient care procedures. Whereas stretch vinyl exhibited lower failure rates than standard vinyl, the higher in-use leakage rates associated with all vinyl gloves tested indicate decreased durability and, potentially, compromised barrier protection when this synthetic is used. Careful consideration to the degree of barrier effectiveness should be given before glove selection when the potential exposure to bloodborne pathogens or biohazard risks is a concern.

Management of acute right heart failure after combined heart and kidney transplantation: case report

Combined heart and kidney transplantation is performed rarely and merits unique fluid-management considerations postoperatively. We present the case of a young man who developed acute right heart failure after combined heart and kidney transplantation and responded to hemofiltration. We believe that the postoperative management of combined heart and kidney transplant recipients should not be different from that of patients receiving a heart transplant only. Intravenous fluids should be administered judiciously, and hemofiltration should be instituted early to remove fluid and reduce preload if right heart failure develops.

Primary esophageal lymphoma: a diagnostic challenge

A 56-year-old man with primary esophageal lymphoma is presented. Diagnosis of this disease can present a challenge. Clinical characteristics, treatment principles, and a detailed discussion of diagnosis are presented. When primary esophageal lymphoma is diagnosed, combination chemotherapy and radiotherapy afford a significant chance of long-term survival.

Angiopeptin inhibits thymidine incorporation by explants of porcine coronary arteries

Angiopeptin, a stable octapeptide analog of somatostatin, inhibits proliferation in a variety of cancer cell lines. We studied the effect of angiopeptin on 3H-thymidine uptake into ring segments from the porcine coronary tree. The incorporation of 3H-thymidine into segments of porcine left anterior descending (LAD) coronary artery was time dependent and reached a plateau after 48 h. The addition of angiopeptin (48.1 and 96.2 nM) to the culture medium significantly inhibited 3H-thymidine incorporation into the segments by 36.7 +/- 10.1% and 48.3 +/- 2.3% of the control, respectively. Forskolin (100 microM), inhibited 3H-thymidine incorporation (52.7 +/- 10.1%) to the same degree as did angiopeptin (96.2 nM). Incubation of the segments with 125I-labeled angiopeptin, for 2 h at 37 degrees C, showed angiopeptin uptake to be time dependent and exhibited a first-order kinetics, reaching equilibrium after 30 min. Autoradiographic studies showed a uniform distribution of angiopeptin within the endothelium, media, and adventitia. Most of the labeling was associated with the nuclei of the cells. Angiopeptin, after 30-min incubation, did not significantly modify the basal levels of cyclic adenosine monophosphate (cAMP). In contrast, forskolin (100 microM) elicited a 50-fold increase of the basal levels of cAMP. These results indicate that in addition to its endocrine effects, angiopeptin reduces the rate of proliferation by acting directly on the vessel wall.

A case with 47,XXY,del(15)(q11;q13) karyotype associated with Prader-Willi phenotype

Herein we present the case of a 12-year-old boy who attended our clinic for obesity and hyperphagia. As a newborn he was noted to have diffuse muscular hypotonia and poor sucking response. At the age of 11 years, he was admitted to hospital for respiratory insufficiency. He had personality disorders characterized by temper tantrums and violent outbursts including self-mutilation. Physical evaluation revealed marked central obesity, he had small hands and feet, and also genital hypoplasia. Of the biochemical parameters, hyperglycemia and a low serum testosterone level must be emphasized. The patient fulfills the clinical criteria of typical Prader-Willi syndrome. Cytogenetic and fluorescence in situ hybridization analysis showed a karyotype 47,XXY, del(15)(q11;q13). To our knowledge this is the first report of the aforementioned genotype expressed as Prader-Willi phenotype in childhood.

Development in a 46 XX boy with positive SRY gene

We present the case of an 11 year-old boy, who asked for medical attention due to obesity and assumed underdeveloped external genitalia. He did not have genital anomalies, penile length was 5.3 cm, testicular volume 2 ml and pubic hair Tanner stage 1. His bone age was normal for chronological age. Endocrinological study showed normal results for his age. Karyotype revealed a 46 XX pattern. MRI of external genitalia showed bilateral scrotal testes which were normal in diameter for his age. The check of his historical growth chart and follow-up revealed normal growth with spontaneous pubertal development. However, hormonal studies showed progressive increase of FSH levels, indicative of failure of germinal epithelium. The presence of Y sequences, including SRY gene, was demonstrated by PCR. Our observation is in agreement with the view that 46 XX male subjects diagnosed at peripubertal age with the SRY gene in the genome have a good prognosis regarding growth and development, but the principal problem of these patients is infertility.

[Cleft sternum in an infant]

The authors report the clinical case of a female black infant, one month 22 days old, with sternal malformation (complete sternal cleft). She didn't show other associated malformations. Early surgical repair was done with success. The relevant nomenclature of sternal defects is discussed.

Estradiol effect on rate of proliferation of rat carotid segments: effect of gender and tamoxifen

Using organ culture of carotid artery segments from sexually mature male and female rats, we examined the effect of estradiol 17 beta on proliferation. The index of cell proliferation was [3H]thymidine uptake. Estradiol 17 beta (0.18-0.36 microM) inhibited the uptake of thymidine in a concentration-dependent manner (p < 0.05). Estradiol 17 beta inhibited [3H]thymidine uptake only in the absence of the weak estrogen receptor agonist phenol red and in carotid artery segments from sexually mature female (p < 0.01) but not male rats. Tamoxifen (0.1 and 1 microM), a partial agonist of estrogen receptors, significantly inhibited thymidine uptake (p < 0.01). However, preincubation of the segments with tamoxifen (0.1 and 1.0 microM) for 4 h before the exposure to estradiol, blocked estradiol 17 beta-induced inhibition of thymidine uptake (p < 0.05 and p < 0.01 for 0.1 and 1.0 microM, respectively). The cyclooxygenase inhibitor indomethacin (5 microM) did not affect either the basal [3H]thymidine uptake or the estradiol 17 beta-induced inhibition of that uptake. This latter finding suggests that prostacyclin or prostaglandin E2 does not mediate the inhibitory response to estradiol 17 beta. The results of these experiments suggest that estradiol 17 beta-induced inhibition of proliferation of rat carotid artery segments is mediated through activation of estrogen receptors.

Interlaboratory comparison of analytical methods for residual ethylene oxide at low concentration levels in medical device materials

An interlaboratory comparison of two extraction methods and one thermal desorption test method for the quantification of ethylene oxide (EO) by gas chromatography in two common medical device materials, high density polyethylene (HDPE) and plasticized polyvinyl chloride (PVC), was conducted by 15 laboratories. The three procedures included extraction with water, extraction with acetone, and headspace gas analysis, respectively. Materials were processed through an industrial EO cycle and aerated for various periods to achieve target levels of a low (5 micrograms/g), medium (10 micrograms/g), and high (25 micrograms/g) residual determination following extraction or thermal desorption. The results of this study, using only the data from the laboratories that did not deviate from the procedure, showed that the average estimated total coefficient of variation ranged from 3.63 to 12.42% for the three different methods. Each of the methods is suitable for use as a reference test method for determining residual EO in polymeric materials in the concentration range 2.8-42.3 micrograms/g.

Effect of estradiol 17 beta on pressor responses of rat mesenteric bed to norepinephrine, K+, and U-46619

We reinvestigated the effect of estradiol 17 beta on the responses of adrenergic and nonadrenergic vasoconstrictors characterized it in terms of steroid specificity, time course, and the role of classic estrogen receptors. We evaluated the effect of estradiol 17 beta on the pressor responses of isolated perfused rat mesenteric vascular bed (McGregor's preparation). Estradiol 17 beta (7-700 nM) significantly increased the pressor response to bolus applications of norepinephrine (NE) (p < 0.05). However, estradiol 17 beta did not significantly increase the responses to endogenous NE release induced by electrical field stimulation. Other steroids, testosterone, and the 17 alpha isomer of estradiol (7 and 700 nM) were ineffective. Estradiol 17 beta (700 nM) also significantly increased the maximum pressor response of rat mesenteric preparation to both the prostaglandin endoperoxide analogue U-46619 and to K+. The potentiation by estradiol 17 beta of mesenteric vasoconstriction elicited by NE, K+, and U-46619 was rapid (2-8 min), suggesting that a nuclear receptor may not be involved. This notion received further support in that significant potentiation of the NE-induced pressor response was also observed with estradiol 17 beta conjugated to albumin (700 nM), but not when electrical field stimulation was used. The conjugate increased the effect of all NE concentrations. Its effect was also more consistent (p < 0.01) than that elicited by free estradiol 17 beta. The dose-response curve was shifted to the left, and the maximum effect was increased. These data suggest that estradiol 17 beta may possess rapid nongenomic actions unrelated to nuclear receptor binding and gene transcription.

Incidence of different forms of thyroid dysfunction and its degrees in an iodine sufficient area

STUDY OBJECTIVE

The aim of the study was to determine the incidence of thyroid dysfunction in an iodine sufficient area (Vigo city, Galicia, North-West of Spain).

DESIGN

Case-finding study during a 3-year (1990-1992) period.

SUBJECTS

Subjects from a random sample of the population with abnormal results on FT4, sensitive-TSH or antithyroid autoantibodies.

MEASUREMENTS

Thyroid size by ultrasound study. FT4 by RIA; TSA Ab by radio receptor assays; TSH, Tg Ab and TMS Ab by IRMA.

MAJOR RESULTS

Overall incidence of thyroid dysfunction was 97.96 per 100,000 per year (CI 95% 78.86-117.06); female 162.45, male 17.44. Incidence rate of hyperthyroidism was 52.37 per 100,000 per year (CI 95% 38.41-66.36); 24.24 for Graves' disease, 11.63 for nodular hyperthyroidism, 13.57 for iatrogenic hyperthyroidism and 2.90 for others causes. Incidence rate of hypothyroidism was 45.58 per 100,000 per year (CI 95% 32.55-58.620 27.15 for hypothyroid autoimmune thyroiditis, 8.72 for postoperative hypothyroidism, 4.89 for miscellaneous hypothyroidism, 1.93 for amiodarone induced hypothyroidism and 2.90 for secondary hypothyroidism.

CONCLUSIONS

This investigation provides extensive data on incidence of clinical and subclinical thyroid dysfunction and its different forms in an iodine sufficient area.

Oestradiol inhibits smooth muscle cell proliferation of pig coronary artery

1. The effect of oestradiol 17 beta on vascular smooth muscle proliferation was examined in segments of the pig left anterior descending coronary artery (LAD). It was established by cytochemical techniques that out-growth from the segments was composed of vascular smooth muscle cells. 2. [3H]-thymidine uptake by pig LAD segments was used as an index of vascular smooth muscle cell proliferation. Nitroprusside and forskolin significantly inhibited [3H]-thymidine uptake and were used as positive controls. 3. Oestradiol 17 beta (180-360 nM) inhibited thymidine uptake by pig LAD segments (P < 0.05). The inhibition was observed only in the absence of phenol red, which is a weak oestrogen receptor agonist. The anti-oestrogens tamoxifen and its more potent metabolite 4-hydroxytamoxifen, both of which are partial oestrogen receptor agonists, also significantly inhibited thymidine uptake. However, pretreatment with either tamoxifen or 4-hydroxytamoxifen did not significantly block oestradiol 17 beta-induced inhibition of thymidine uptake. 4. The LAD segments bound [3H]-oestradiol 17 beta in a time-dependent manner and about 20 to 30% was displaced by an excess of unlabelled oestradiol 17 beta. Autoradiography showed [3H]-oestradiol 17 beta was evenly distributed in the cytosol and nuclei of cells in the three layers of the vessel wall. 5. The data suggest that oestradiol 17 beta inhibits smooth muscle cell proliferation in porcine LAD segments, possibly through an oestrogen receptor mechanism. This in vitro effect suggests an in vivo role for oestradiol 17 beta in directly protecting coronary arteries against myointimal proliferation in premenopausal women.

[Clinical considerations about psychopathy and delinquency]

Clinical differences the authors find between the psychopath's, and the offender's personalities organization are discussed. The authors disagree with an existing pattern tending to include both kinds of personalities under the sole denomination of antisocial personality--a concept they find fit for any discipline other than clinical psychology. Thus, a nosographic separation is set up by analyzing the different responses both organizations yield when facing some basic situations.

Systemic vascular effects of cyclosporin A treatment in normotensive rats

The immunosuppressive drug cyclosporin A (CsA) frequently induces hypertension, but the mechanism(s) is unknown. Thus, we examined the mechanism(s) by which CsA increases arterial blood pressure (MAP) in the normotensive rat. Three different treatment modalities were used. First, chronic CsA treatment (20 mg/kg/day, s.c., for 1 week) significantly increased MAP from 109.6 +/- 2.3 mm Hg to 125.8 +/- 2.9 mm Hg (P less than .05). Second, subacute i.v. infusion of CsA (20 mg/kg daily for 3 days) increased MAP to even higher values (140.5 +/- 2.3 mm Hg), which correlated significantly with the highest circulating values of the drug. The pressor effect after i.v. infusion appears to be unrelated to endogenous release of catecholamines, because phentolamine, which abolishes the response to exogenous norepinephrine, failed to prevent the CsA-induced pressor response. Third, i.v. bolus injections of CsA (10-20 mg/kg) evoked immediate, dose-dependent and short-lasting increases in MAP (+15-25 mm Hg) in both anesthetized and conscious rats. Ganglionic blockade did not prevent this effect, rather, a 2- to 3-fold increase in amplitude (+40-60 mm Hg) and duration (+30-45 min) of the CsA-induced pressor response was observed in anesthetized rats. Heart rate was not increased significantly by either acute or chronic administration of CsA. Our results suggest that both CsA-induced pressor responses and hypertension are due to a peripheral action unrelated to sympathetic outflow. Furthermore, CsA's hypertensive effect is accompanied by severe morphological changes in the vascular endothelium and smooth muscle cells. In addition, CsA-treated rats showed significantly attenuated vasodilatory responses to prostacyclin and sodium nitroprusside, and increased pressor responses to norepinephrine. Thus, a direct vascular action of CsA is likely to contribute to the alterations on systemic vascular responsiveness, as well as to the hypertensive effect of the drug.

Mechanism of cyclosporin potentiation of vasoconstriction of the isolated rat mesenteric arterial bed: role of extracellular calcium

Hypertension is a serious side-effect of the clinical use of Cyclosporin A (CsA). One notion is that alterations of vascular reactivity contribute to this hypertension. In this study we used the isolated rat mesenteric vascular bed to test the specific hypothesis that CsA modifies vascular calcium regulation to potentiate vascular contractility. Mesenteric vessels from CsA-treated rats (10 mg/kg/day i.m. for 7 days) exhibited significantly greater vasoconstrictor responses to exogenous norepinephrine (NE) and potassium-induced depolarization than those of vehicle-treated animals. Similarly, in vitro CsA (8.3 X 10(-8) to 8.3 X 10(-6) M) augmented in a concentration-dependent manner both the sensitivity and the maximum response to NE and potassium. This effect of CsA on vasoconstriction was critically dependent on the presence of external calcium [( Ca++]o). The degree of vasoconstriction potentiation correlated significantly with the [Ca++]o which was used during exposure of the mesenteric bed to CsA. Reapplication of external calcium in the presence of CsA to "calcium-depleted" preparations increased significantly the amplitude of subsequent NE responses in a calcium-free medium. Thus, CsA-potentiated NE responses, once established, were not reversed by removing external calcium; however, attenuation occurred with the intracellular calcium antagonist dantrolene. Verapamil and nifedipine blocked potassium-elicited responses, but failed to prevent the CsA effect on NE-induced vasoconstriction. We conclude that CsA potentiation of vasoconstriction depends on extracellular calcium, and results from an enhanced transmembrane calcium transport. We speculate that CsA also increases the filling of intracellular stores of releasable calcium. These effects lead to greater calcium influx and greater intracellular calcium release upon stimulation.

Attenuation of vascular relaxation and cyclic GMP responses by cyclosporin A

The effect of Cyclosporin A (CsA) on vascular vasomotor responses was determined in two isolated tissue preparations. The first preparation was the rat mesenteric vascular bed which was constricted by phenylephrine (EC80) and perfused with CsA (8.32 x 10(-8) to 8.32 x 10(-6) M). Vasodilation responses to acetylcholine, bradykinin and the calcium ionophore, A23187, were impaired, as was the response to sodium nitroprusside at high CsA concentrations. Indomethacin had no effect suggesting that the CsA effect is unrelated to the synthesis of cyclooxygenase products. In the second preparation, thoracic aortic rings from rats treated with CsA (5-10 and 20-50 mg/kg/daily for 3 and 1 weeks, respectively) were used. Aorta rings precontracted by phenylephrine (EC80) also showed impaired responses to both endothelium-dependent (acetylcholine) and endothelium-independent (sodium nitroprusside) vasodilators. Furthermore, a marked decrease of the guanosine 3',5'-cyclic monophosphate (cGMP) content in aortic preparations was found to accompany the in vivo effect of CsA on relaxation. In addition, exposure of aortic rings to CsA (8.32 x 10(-8) to 8.32 x 10(-6) M) in vitro, also inhibited markedly the cGMP response induced by acetylcholine or sodium nitroprusside. This effect of CsA was not modified by isobutyl methylxanthine, a phosphodiesterase inhibitor. We conclude that CsA acts directly on the vascular smooth muscle; and speculate that CsA may compromise the response to vasodilators by inhibiting cGMP formation.

Simultaneous determination of hydrocortisone and benzyl alcohol in pharmaceutical formulations by reversed-phase high-pressure liquid chromatography

An accurate, reproducible, and specific reversed-phase high-pressure liquid chromatographic (HPLC) procedure that simultaneously determines hydrocortisone and benzyl alcohol in a variety of pharmaceutical formulations is presented. Cream, gel, ointment, and solution formulations containing varying hydrocortisone and benzyl alcohol concentrations can be analyzed with only minor modifications in sample preparation. To provide optimum accuracy and reproducibility, phenethyl alcohol is used as an internal standard. The specificity of the procedure allows for the quantitative determination of hydrocortisone and benzyl alcohol in the presence of their degradation products and without interference from the phenethyl alcohol. The determinations can be performed with an analysis time of 10-13 min/sample.

The chemistry and conformational and biological analysis of vitamin D3, its metabolites and analogues

The chemical properties, stereochemical relationships and solution conformation, as assessed in part by proton NMR spectroscopy, for vitamin D3, its major metabolites [including 1alpha,25-(OH)2D3, its hormonally active form] and a number of A-ring and side chain analogues are evaluated and discussed in relation to their biological activity. In particular the relative ability of many of these seco-steroids to compete both with 25-OHD3 for its chick serum binding protein and 1alpha,25-(OH)2-D3 for its chick intestinal cytosol-chromatin receptor system was quantitated, in vitro. Further, the relative effectiveness of all these metabolites and analogues to mediate in vivo intestinal calcium absorption and bone calcium mobilization was determined. Collectively these chemical and biological studies constitute a "systems analysis" of the various steroid structural parameters both required and tolerated by the multi-stepped endocrine system associated with the biological actions of vitamin D.