P-352 Consequences and prevalence of Bacterial Vaginosis and vaginal leukocytosis on Live Birth rate after IVF - Nugent score : What else?

Study question

Do altered vaginal microbiota, and vaginal leukocytosis, both estimated by the Nugent score, influence live birth rates in IVF after a fresh embryo transfer?

Summary answer

In our series, Nugent score is able to diagnose Bacterial Vaginosis and predict its bad influence in live birth rates after fresh embryo transfer.

What is known already

For several years, special attention has been given to vaginal microbiota and vaginosis as part of IVF and embryo implantation failure.

Lactobacillus is recognized as dominant in a healthy vaginal microbiota environment while gardnerella is more present in a vaginal microbiota altered and bacterial vaginosis.

While all published studies are mostly meta-analysis, the originality of our study is the number of patients (967) tested in a single laboratory and taken care of by one center only. This study also reports the influence of the microbiota and leucocytosis on LBR.

Study design, size, duration

This study is a retrospective, a non-interventional monocentric cohort study conducted between January 2017 and December 2019. 967 patients benefited from Nugent score for bacterial vaginosis before the start of treatment or within the first week of injections for IVF protocol. No patient was treated by antibiotics.

Participants/materials, setting, methods

The swab obtained during speculum examination and smeared onto a glass-slide was left to dry at room temperature and then Gram Stained and Nugent score were calculated according to recommendations (Nugent et al., 1991). Bacterial Vaginosis (BV) was diagnosed for Nugent scores of 7 –10 (Group 3) and a score of 4 – 6 (Group 2) was considered intermediate flora (Nugent et al., 1991).In the same way, presence and abundance of leukocytes were recorded.

Main results and the role of chance

BV prevalence estimated by Nugent score in the total population is of 6.52% (63/967). There is no difference between the three Nugent groups regarding demographics criteria.

BV in endometriosis population is of 8.07% (18/223), in patients with tubal infertility 10.46% (18/172) and in patients with male infertility 5.51% (17/353).

The presence of Lactobacillus depends on the age and it is (p = 0.4) statistically more present in older patients while the presence of gardnerella depends on infertility indication. Gardnerella is more represented in tubal indications and the difference is statistically significant (p = 0.01).

Concerning leukocytosis (numerous, relatively numerous and few leukocytes) or no (rare leukocytes) the difference is statistically significant between pregnancy and failure after embryo transfer (p = 0.014). Leukocytosis is more involved in vagina when the IVF failed.

BV prevalence in patients who became pregnant after embryo transfer is of 3.47% (8/230) while BV in patients with IVF failure is of 7.22% (48/664) (p = 0.05).

Concerning Live Birth rate, there are statistically significant differences between Group 1 (152/192) and Group 2 (14/24) (p = 0.03), and between Group 1 and Group 3 (8/16) (p = 0.01) but no difference between Group 2 and 3 (p = 0.74). Moreover, in tubal indications, the presence of gardnerella is significantly associated with miscarriage (p = 0.001)

Limitations, reasons for caution

Our study is retrospective, which may introduce several biases despite the size of our sample i.e all infertility etiologies were included and no differences were made based on the ethnic origins of the patients, which may have resulted in biases.

Wider implications of the findings

Nugent score is able to diagnose BV and predict its bad influence in both etiology of infertility and pregnancy outcome after fresh embryo transfer.

Nugent score allows to define intermediate group and vaginal leukocytosis to which special attention should be paid as it may compromise a pregnancy.

Trial registration number

NOT APPLICABLE

P-295 Impact of Nugent score and microbiota on live birth rate after fresh embryo transfer in women with endometriosis? A tool not to be neglected!

Study question

Do altered vaginal microbiota, and vaginal leukocytosis, both estimated by the Nugent score, influence live birth rates in IVF after a fresh embryo transfer in women with endometriosis?

Summary answer

Nugent score is able to diagnose Bacterial Vaginosis and predicts its bad influence in live birth rates after fresh embryo transfer in women with endometriosis.

What is known already

For several years, special attention has been given to vaginal microbiota and vaginosis as part of IVF and embryo implantation failure.

Lactobacillus is recognized as dominant in a healthy vaginal microbiota environment while gardnerella is more present in a vaginal microbiota altered and bacterial vaginosis.

While all published studies are mostly meta-analysis, the originality of our study is the number of patients with endometriosis (223) tested in a single laboratory and taken care of by one center only. This study also reports the influence of the microbiota (gardnerella especially) and leucocytosis on LBR in case of endometriosis.

Study design, size, duration

This study is a retrospective, a non-interventional monocentric cohort study conducted between January 2017 and December 2019. 223 patients with endometriosis benefited from Nugent score for bacterial vaginosis before the start of treatment or within the first week of injections for IVF protocol. No patient was treated by antibiotics before the swab.

Participants/materials, setting, methods

Nugent score is Gram stained scoring (scale of 0 to 10) of bacterial morphotypes from vaginal smear samples calculated according to recommendations. Scores of 0-3 (Group 1) indicates normal flora, scores of 4-6 (Group 2) is considered intermediate flora and scores of 7-10 (Group 3) is diagnosed Bacterial Vaginosis (BV) (Nugent et al., 1991). In the same way, presence and abundance ok leukocytes were recorded

Main results and the role of chance

BV in endometriosis population is of 8.07% (18/223), There is no difference between the three Nugent groups regarding demographics criteria.

Concerning microbiota per se the presence of Lactobacillus is depending of age and it is statistically more represented in older patients (p = 0.04) while the presence of gardnerella is depending of indication.

Gardnerella is more represented in tubal indications and the difference is statistically significative (p = 0.01).

Concerning leukocytosis (numerous, relatively numerous and few leukocytes) or no (rare leukocytes) the difference is not statistically significant between pregnancy and failure after embryo transfer (p = 0.7).

Concerning Live Birth rate, the result is statistically different between Group 1 (31/37) versus Group 2 and Group 3 gathered (3/11) (p = 0.0008).

Furthermore, in this population with endometriosis, gardnerella is significantly associated with miscariage (p=.001)

When pregnancy has progressed favorably, the terms of delivery is not different between the three groups as well as the weight of newborns.

Limitations, reasons for caution

Our study is retrospective, which may introduce several biases despite the size of our sample i.e all all endometriosis stages were included and no differences were made based on the ethnic origins of the patients, which may have resulted in biases.

Wider implications of the findings

Nugent score is able to diagnose BV and predict its bad influence on pregnancy outcome after fresh embryo transfer in endometriosis patients.

Nugent score and its microbiota study draws the attention in this series on endometriosis patients group infected by gardnerella as it may compromise a pregnancy.

Trial registration number

NA

P–324 Pregnancy outcome after IVF for endometriosis or male infertility: What differs?

Study question

Are endometriosis women pregnant after IVF at increased risk of preeclampsia or placenta praevia than patients monitored for male infertility?

Summary answer

Patients with endometriosis are at greater risk than patients monitored for male infertility of developing preeclampsia and placenta previa.

What is known already

Endometriosis is a chronic estrogen-dependent disease that affects women of childbearing age which represents 10% of the general population[.The main symptoms found are chronic pelvic pain, infertility, dyspareunia and dysmenorrhea. Numerous publications have highlighted the deleterious effect of endometriosis on pregnancy i.e miscarriage, placental abnormalities, preeclampsia, preterm birth, low gestational weight. This complication may be related to the molecular and cellular abnormalities present in the endometrium of these patients and to the inflammatory state that may lead to abnormal contractility of the uterus at the time of the implantation window and trophoblastic invasion.

Study design, size, duration

This study is a retrospective, non-interventional monocentric cohort study conducted between January 2011 and December 2017 in Institut de Medecine de la Reproduction - Clinique Bouchard in Marseilles, France.

Participants/materials, setting, methods

The outcome of pregnancies obtained after IVF and/or ICSI in patients with endometriosis (n = 270) was compared with patients,free of endometriosis,monitored for male infertility (n = 366) The statistical study was carried out using GraphPad Version 8 The Student T-test was used to compare means across them. Results were considered significant for p < 0.05.

Main results and the role of chance

Patients with endometriosis and monitored during this period were older than those managed for male infertility. (33.59 vs 32.78) (p = 0.04). There was no difference between the two populations regarding BMI (p = 0.31) or smoking (p > 0.9). The rate of miscarriage observed in the two populations was comparable (25.37 vs. 25.78%) (p > 0.9), so was the rate of IUGR (5.81% vs. 2.29%) despite the observed percentages (p > 0.9). The rate of premature deliveries did not differ between the two populations (18.37% vs. 14.29%) (p = 0.55) neither did the number of children born with a weight <2500g at term (13.68% vs. 12.5%) (p = 0.83). Although the rate of gestational diabetes was comparable in both groups (4.11% vs 4.56%), the rate of preeclampsia was higher in the group of patients with endometriosis with a statistically significant difference (4.79% vs 0.79%) (p = 0.01). Similarly, the rate of placenta previa was higher in patients with endometriosis (4.11% vs 0.76%) (p = 0.02). All pregnancies complicated by placenta previa resulted from J2/J3 embryo transfer. Estradiol levels on the day of induction (2166 pg/ml vs 2452) (p = 0.67) and endometrial thickness was not different between patients with placenta praevia or no (10.45 vs 10.51) (p = 0.66).

Limitations, reasons for caution

Our study is retrospective which may introduce several biases despite the size of our sample i;e patients with endometriosis are older, adenomyosis was not included in the criteria. In our study we have not found any additional risk related to the type of embryo transferred.

Wider implications of the findings: Patients with endometriosis are at greater risk than patients managed for male infertility of developing preeclampsia and placenta previa. It is advisable to warn patients of this possible complication, to promote e-SET and to set up early monitoring in order to place the appropriate management around these patients.

Trial registration number

Not applicable

Further evidence of a prolonged hypotensive and a bradycardic effect after mandibular extension in normal volunteers

We previously reported that in normotensive humans submaximal mouth opening (mandibular extension) obtained by an ad hoc dilator (spring device), associated with partial masticatory movements and prolonged for 10 minutes is followed by a long-lasting reduction of blood pressure (BP) and heart rate (HR). Similar results were obtained by us in anesthetized rats. A recent independent study failed to confirm the results in the normotensive human. We reassessed, in 25 normotensive volunteers, the effects on BP and HR of mandibular extension obtained by the spring device associated with partial masticatory movements compared to a control procedure, consisting in keeping a tongue depressor between the incisor teeth. Both procedures were applied for 10 minutes and systolic BP (SBP), diastolic BP (DBP) and HR were measured every 10 minutes by an automatic recorder, for 30 minutes before and 120 minutes after the procedures in seated subjects watching nature documentary films on laptop screen.Baseline levels (mean of the last 3 measurements before procedure) did not significantly differ between the experimental and control sessions. Two way repeated measures ANOVA on absolute (recorded) values did not reveal a significant main effect of treatment for SBP, DBP and HR, but a significant main effect of time (P<0.001) for BP and HR. In addition, a significant interaction of time and treatment was found for SBP (P<0.001) and DBP (P=0.005), but not for HR. In addition, two way repeated measures ANOVA was done on changes from baseline obtaining a significant main effect of treatment (P<0.001) and time (P<0.001) and a significant interaction of time and treatment for SBP (P<0.001) and DBP (P<0.01). Post-hoc comparisons revealed significantly lower values for SBP and DBP in experimental compared to control values at almost all times and this decrement was by about 5 mmHg. Furthermore, for both absolute values and changes from baseline, the interaction effect was, for BP, of a qualitative type as indicated by an opposite effect in the time-course between control and experimental sessions. This study thus provides confirmatory evidence that submaximal mouth opening for a relatively brief time is followed by prolonged albeit small reductions of BP in normotensive human volunteers.

Persistent effects after trigeminal nerve proprioceptive stimulation by mandibular extension on rat blood pressure, heart rate and pial microcirculation

The trigemino-cardiac reflex is a brainstem reflex known to lead to a decrement in heart rate and blood pressure, whereas few data have been collected about its effects on the cerebral hemodynamic. In this study we assess the in vivo effects of trigeminal nerve peripheral stimulation by mandibular extension on pial microcirculation and systemic arterial blood pressure in rats. Experiments were performed in male Wistar rats subjected to mandibular extension obtained inserting an ad hoc developed retractor between the dental arches. Mean arterial blood pressure and heart rate were recorded and the pial arterioles were visualized by fluorescence microscopy to measure the vessel diameters before (15 minutes) during (5-15 minutes) and after (80 minutes) mandibular extension. While in control rats (sham-operated rats) and in rats subjected to the dissection of the trigeminal peripheral branches mean arterial blood pressure, heart rate and pial microcirculation did not change during the whole observation period (110 minutes), in rats submitted to mandibular extension, mean arterial blood pressure, heart rate and arteriolar diameter significantly decreased during stimulation. Afterward mean arterial blood pressure remained reduced as well as heart rate, while arteriolar diameter significantly increased evidencing a vasodilatation persisting for the whole remaining observation time. Therefore, trigeminal nerve proprioceptive stimulation appears to trigger specific mechanisms regulating systemic arterial blood pressure and pial microcirculation.

Effect of canrenone on the digitalis site of Na+/K(+)-ATPase in human placental membranes and in erythrocytes

It has been reported that canrenone, which is used in hypertensive therapy as an antialdosteronic drug, may also act as a blocker of ouabain effects. Several studies suggest that human plasma contains an endogenous ouabain-like factor similar to ouabain, which may be increased in hypertension, in pregnancy, and in the neonatal state. This study evaluated (1) the effect of canrenone on Na+/K(+)-ATPase in relation to ouabain in human placental membranes and erythrocytes by 3H-ouabain binding assay; (2) the capacity of canrenone (10 microM) to reverse the inhibition of Na+/K(+)-ATPase by ouabain and by ouabain-like factor (from umbilical cord plasma) in human erythrocytes employing a 86Rb uptake assay. Increasing concentrations of canrenone (0-350 microM) partially competed with 3H-ouabain binding in placental membrane (40%) and erythrocytes (60%). Scatchard plot from radioreceptor assay in placental membrane showed that ouabain and canrenone compete for the same binding site. In erythrocytes, canrenone completely reversed the inhibition caused by ouabain (5 x 10(-9) M) and ouabain-like factor (2 x 10(-9) M ouabain equivalents). A reduction of inhibition of about 50% was observed with ouabain and ouabain-like factor respectively at a concentration of 5 x 10(-8) M and 2 x 10(-8) M (ouabain equivalents). Our results thus provide evidence that canrenone, at therapeutical concentrations, is a partial competitive agonist of ouabain and of ouabain-like factor in human placental membranes and erythrocytes.

Are serum inhibin concentrations new markers of placental tumours in the course of chemotherapy?

BACKGROUND

The study was conducted to evaluate whether the detection of serum molecular forms of inhibin (A and B) could be useful for the diagnosis, prognosis and follow-up of placental tumours.

METHODS

A total of 17 patients with hydatidiform mole (n = 13), invasive mole (n = 1) or choriocarcinoma (n = 3) were studied; serum concentrations of inhibins A and B, human chorionic gonadotrophin (HCG) and its free beta subunit (HCGbeta) were measured before chemotherapy (after mole evacuation for eight patients) and also during the course of chemotherapy (for 10 patients).

RESULTS

After evacuation or before chemotherapy for refractory disease, serum inhibin A and B concentrations were found to be increased in 10/17 and 4/17 patients, when HCG and HCGbeta were high in all patients. In 10 patients with a follow-up during treatment, nine had a high concentration of inhibin A which correlated with those of HCG and HCGbeta. Normalization of inhibin A was faster than that of HCG and HCGbeta for three and six patients respectively. There was no correlation between changes of inhibin B and HCGbeta concentrations.

CONCLUSIONS

Our results suggest that inhibins A and B are not useful markers and that HCG determination still remains the most useful marker for diagnosis and follow-up of placental tumours.

Increased circulating levels of ouabain-like factor in patients with asymptomatic left ventricular dysfunction

BACKGROUND

Much evidence has been accumulated that human plasma contains digitalis-like factor(s) with Na/K ATPase inhibitor properties. Increased concentrations of ouabain-like factor (OLF) have been reported in patients with moderate to severe hypertension and in patients with overt congestive heart failure due to dilated cardiomyopathy.

AIM

The presence of circulating OLF has not been investigated in borderline to mild hypertension or in the early stage of dilated cardiomyopathy.

METHODS AND RESULTS

The study population consisted of 18 normal volunteers, 24 patients with borderline to mild hypertension, 47 patients with asymptomatic left ventricular dysfunction (ALVD) due to dilated cardiomyopathy and 26 patients with cardiac arrhythmias but normal left ventricular function. OLF values (pM ouabain equivalent) were assayed in extracted plasma, using a radioimmunoassay for ouabain. OLF was, respectively, 29.4+/-20.6 pM in normal controls, 39.1+/-23.8 pM in hypertensives, 35+/-18 pM in patients with cardiac arrhythmias, 52.3+/-25.8 pM in ALVD patients not treated with digoxin and 64.6+/-29.6 pM in ALVD patients treated with digoxin. Patients with ALVD, both treated and not treated with digoxin, had OLF significantly higher (P<0.05) than all the other groups. In patients with ALVD no correlation between OLF and left ventricular ejection fraction was observed. In the hypertensive group no correlation between OLF and both diastolic and systolic pressure was found.

CONCLUSION

Increased concentrations of OLF were observed in patients with left ventricular dysfunction due to dilated cardiomyopathy, before the occurrence of overt heart failure, suggesting that OLF may be an early marker of the disease.

[Mesogastrectomy in the surgical treatment of gastric carcinoma. Experience with 61 cases]

BACKGROUND

In gastric cancer surgery, to search for a technique to remove the entire posterior mesogastric region using a standardised operation using well defined methods and anatomic-embryological planes.

METHODS

A concise description of the embryological evolution of the posterior mesogastrium allow the formation of the mesogastric fascia (and the supramesocolic fascia of the omentum--which is a continuation) to be documented. It is also clear that the mesogastric fascia is the embryological--anatomical equivalent of Treitz's fascia, pancreatic retro-head, and Toldt's retrocolic fascia, of which it is a structural continuation. Like Treitz's and Toldt's fascias, the mesogastric fascia also represents the surgical plane for the detachment of the region in question and allows maximum safety and radicality. By carrying out primary ligature of the arteries at the origin and the veins at the outlet, the entire posterior mesogastric region, with the relative lymph node stations, can be removed en bloc with maximum radicality and safety, and also in line with the principle of "no touch isolation". We used this technique to operate 61 cases, 17% of all cases of gastric carcinomas between 1973 and 1994.

RESULTS

Mesogastrectomy was required in 87% of cases with carcinoma in a high localisation or widespread nature of the linitis plastica type. Only 23 cases (37%) were at pTNM II and III A stages. Thirty-eight cases (63%) were at stages III B and IV. In non-selected cases and those with severe associated pathologies and undergoing emergency surgery, and those cases that were extended beyond mesogastrectomy, morbidity was above all linked to pleural effusion. There were only 2 cases (3%) of operating mortality owing to two technical errors: an esophago-jejunal anastomotic dehiscence (the only case in the series, 1.6%) caused by esophageal cancer nests in the suture and a case of necrosis in the left hepatic region following the section of the left gastric artery at the origin despite the existence of a large hepatic collateral vessel. The results for stages II and III A were excellent: stage II, 100% survival at 5, 10 and 15 years; stage III A 88% survival at 5 years, 70% at 10 years, 55% at 15 years, but only two deaths from neoplasia at 2.7 and 4.6 years. The results for stages III B and IV are comparable to large series undergoing traditional forms of surgery. Postoperative conditions of nutrition and quality of life were good and patients resumed activities with the aid of constant chlorhydric-peptic replacement treatment and the total extraction of gastric mucosa.

CONCLUSIONS

We believe that mesogastrectomy represents a real advance in both technical terms and results for stages II and III A; it is debatable for stages III B and IV, although individual cases who survived for more than 10 years were also reported. The case of a stage pT3N0M1 = IV pathology, with a single hepatic metastasis that increased until one year and then spontaneously resolved leaving the patient alive and in good health 20 years and 6 months after the operation is truly amazing.

Selective inhibition of human erythrocyte Na+/K+ ATPase by cardiac glycosides and by a mammalian digitalis like factor

Na+/K+ATPase is a transport membrane protein which contains the functional receptor for digitalis compounds. In this work we compare the inhibition curves of Na+/K+ATPase measured by the inhibition of 86Rb uptake in human red blood cells by cardiac glycosides and by an endogenous digitalis like factor (EDLF) extracted from human newborn cord blood. The curves of Na+/K+TPase inhibition show a monophasic shape for ouabain, strophantidin, digitoxin, proscillaridin and EDLF whereas a biphasic shape for ouabagenin, digoxin, digoxigenin and digitoxigenin. All the drugs are potent inhibitors of erythrocyte Na+/K+ATPase with an IC50 ranging from 1.8 x 10(-9) M to 1.4 x 10(-11) M for the higher affinity binding site and from 1.8 x 10(-6) M to 5.5 x 10(-9) M for the lower affinity site. Digitoxigenin is the most active showing the higher active site at 1.4 x 10(-11) M. Ouabain and digoxin have higher affinity compared with their corresponding genins, while digitoxigenin shows a binding site with higher affinity than the respective cardiac glycosides. The increased affinity of the drugs to Na+/K+ATPase may be related to a lipophilic region in correspondence of the carbons 10, 9, 11, 12, 13 of the steroid nucleus, situated in the opposite side with respect of the C-OH-14. The comparison of the inhibition curves and the HPLC profile of newborn EDLF and of the investigated cardenolides suggest that EDLF may be a compound identical or very similar to ouabain.

Endogenous digitalislike factors in obstructive sleep apnea

Recent studies have provided evidence that hypoxia may stimulate the release of endogenous digitalislike factors (EDLF). Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia during sleep and may be associated with sympathetic activation and a high risk of developing hypertension. This study was designed to measure EDLF in the plasma of patients with OSA diagnosed by polysomnography, with patients being classified by the number of apneic-hypopneic episodes/h sleep (apnea-hypopnea index, AHI). Plasma was obtained in the morning from 8 male normotensive OSA patients (OSA-N) (AHI 70+/-6), 2 untreated hypertensive OSA patients (OSA-HT), and 11 age-matched healthy male controls (C). EDLFs of different hydrophobicities were separated from the same plasma sample by solid-state C18-cartridges with 25% acetonitrile (ACN) (EDLF-1) followed by 40% ACN (EDLF-2). This procedure recovered ouabain in the first fraction and digoxin and digoxigenin in the second. EDLF was quantified in pM ouabain-equivalents by a human placenta radioreceptor assay. EDLF-1 levels were similar for OSA-N and C (231+/-55 vs. 258+/-58), whereas EDLF-2 levels were increased in OSA-N (244+/-51 vs. 110+/-25 in C, p=0.02). Norepinephrine was increased in apneics. The two OSA-HT had EDLF and norepinephrine levels similar to OSA-N. These preliminary results suggest that OSA is associated with an increase in the more hydrophobic EDLF levels in both normotensive and hypertensive states. No significant increase was found for the less hydrophobic ouabain-like EDLF.

Exposure to a hypogeomagnetic field or to oscillating magnetic fields similarly reduce stress-induced analgesia in C57 male mice

Previous studies have shown that exposure to altered magnetic fields alters analgesic responses in a variety of species, including humans. Here we examined whether deprivation of the normally occurring geomagnetic field also affects stress-induced analgesia, by measuring the nociceptive responses of C57 male mice that were restraint-stressed in a hypogeomagnetic environment (inside a mu-metal box). Stress-induced analgesia was significantly suppressed in a manner comparable to that observed in mice that were either exposed to altered oscillating magnetic fields or treated with the prototypic opiate antagonist naloxone. These results represent the first piece of evidence that a period in a hypogeomagnetic environment inhibits stress-induced analgesia.

[The single-stage surgery of colorectal neoplastic occlusion. The experience of 133 cases]

BACKGROUND AND AIM

133 cases of occluded colorectal neoplasms (14% of the entire series): 30 (23%) of the right colon, 103 (77%) of the left colon-rectum; 69 males (52%) and 64 females (48%); mean age 67.5 years old, range 33-91 years. pTNM: stage II, 28 cases (21%); stage III: 43 cases (32%); stage IV, 62 cases (47%). The aim of this study was to resolve the occlusive symptoms and to treat the neoplasm in a single operation.

METHODS

In the 62 cases at stage IV, surgery was solely palliative: 49 (79%) derivations, 13 (21%) entero-enterostomies and 36 (58%) preternatural anus; 11 (18%) standard hemicolectomies, extended in two cases to hepatic resection, and 2 (3%) Hartmann's operations. In the 71 cases at stages II and III, surgery took the form of standard colic exeresis with primary ligature of the colonic vessels at source and at the outlet; 15 (21%) right colectomies, 50 (70%) left colectomies, extended in 6 cases (8%) to abdomino-perineal amputation; 6 segmentary colectomies, 3 (4%) of the transverse colon and 3 (4%) Hartmann's operations. The following aspects are essential in this single-stage surgery: urgency; massive dose antibiotic treatment limited to the pre- and perioperative stages; peritoneal cleansing using accurate, methodical, repeated and abundant lavage; perioperative colonic preparation using direct colotomic perioperative lavage or using a trans-buccoenteric access (using Grosz-Dennis tube); the peritonisation of the retroperitoneum with the omentum and the protection of the anastomosis using omental wrapping and active lavage and, for colorectal anastomosis, even using the 3-way tube, lavage and active aspiration, in a transanal trans- or sub-anastomotic position. Total parenteral feeding is useful for 6-7 days.

RESULTS

In the 62 cases at stage IV, postoperative morbidity was 3 cases (6%): 3 suppurations of laparotomy, and mortality occurred in 10 cases (16%): one case of anastomotic disunion (pre-Gullino's tube), 3 cases of septic shock and 6 cardiorespiratory failures. Mean postoperative hospitalisation was 14 days. All these patients died owing to the spread of neoplasms within 1-40 months, mean 13 months. The worst results were obtained in entero-enterostomies: 1-9 months, mean 5 months. In the 71 cases at stages II and III, postoperative morbidity was 3 cases (4%): a small anastomotic filtration after right colectomy and 2 suppurations of the laparotomic incision; mortality amounted to 10 cases (14%): one case of septic shock, one of acute hepatitis, one intestinal infarction and one cardiac infarction, 3 pulmonary embolisms and 3 cardiorespiratory failures. Mean postoperative hospitalisation was 13 days, only 10 in cases of left colectomy with anastomosis protected by Gullino's tube. The long-term results were very good in these 71 patients: over 5-year survival of 50% (Kaplan-Meier).

CONCLUSIONS

Using this courageous single-stage surgery, the results are optimal even at a distance, together with reduced surgical trauma and a shorter hospital stay.

Detection of digitalis compounds using a surface plasmon resonance-based biosensor

An automated surface plasmon resonance-based biosensor system has been used to detect endogenous and exogenous digitalis-like factors (EDLF) in the pmolar range in real time. EDLF was purified from umbilical cord blood. EDLF has been suggested to play a role in hypertension and in perinatal adaptation. Highly specific polyclonal anti-ouabain antibodies showed a high affinity binding capacity for ouabain, ouabagenin and strophantidin with an IC50 value of 5 x 10(-10) M, 7.0 x 10(-10) M and 2 x 10(-8) M, respectively. EDLF cross-reacted with antibodies and its concentration in plasma at IC50 was around 50 pmol ouabain equivalent. This study shows the potential usefulness of the biosensor technology for biomolecular interaction analysis. The features of this technology (fully automated, measured in real time, sharpened response) offer several advantages compared with a traditional immunoassay like radioimmunoassay (RIA) in the detection of digitalis compounds in human fluids.

Do geomagnetic disturbances of solar origin affect arterial blood pressure?

OBJECTIVE

Episodic reports suggest that geomagnetic disturbances of solar origin are associated with biological and clinical events, including increased arterial blood pressure (BP). We reassessed this aspect by relating solar activity levels to ambulatory BP measured in our out-patient population.

PATIENTS AND METHODS

The ambulatory BP measurements of 447 consecutive untreated patients attending a hypertension out-patient clinic who did a monitoring for diagnostic purposes over 5 years were retrieved. The mean daytime, night-time and 24-h BP and heart rate values were related to the temporally corresponding geomagnetic index k-sum obtained by the nearest observatory. K-sum is a local measurement of the irregular disturbances of the geomagnetic field caused by solar particle radiation.

RESULTS

Significant to highly significant positive correlations were observed for k-sum with systolic (daytime and 24 h) and diastolic BP (daytime, night-time and 24 h), but not with heart rate. No correlations were found with the k-sum of 1 or 2 days before the monitorings. Multiple correlations which also included other potential confounding factors (date, age) confirmed a significant effect of k-sum on BP. Comparison made in season-matched subgroups of quiet and disturbed days (using three different criteria of definition), always showed significantly higher values in the disturbed days for all BP parameters except systolic night-time pressure. The difference between the quietest and the most disturbed days was of about 6 to 8 mm Hg for 24-h systolic and diastolic BP.

CONCLUSION

These results are unlikely to be due to unrelated secular trends, but seem to reflect a real relation between magnetic field disturbances and BP.

Inhibition of rat Na+/K+-ATPase isoforms by endogenous digitalis extracts from neonatal human plasma

An unique endogenous digitalis-like factor (EDLF) has been previously purified from human newborn cord plasma and its differential effects tested on the three well defined functional isoforms (alpha1, alpha2 and alpha3) of the alpha subunits of Na+/K+-ATPase in rat. EDLF specifically inhibits the enzymatic activity. It differs from ouabain by three criteria: a preincubation with the membranes is required for full activity, no effect on the rat cerebral alpha3 isoform and a steep dose-response curve with the same apparent potency for rat alpha2 and alpha1 isoforms of high (10(-7) M) and low affinity (3 x 10(-5) M) for ouabain. These results indicate that the Na+/K+-ATPase inhibitor involved in the regulation of sodium and body fluid volume and present in neonate and adult human plasmas is distinct from ouabain.

Ultrasonic myocardial texture in hypertensive mild-to-moderate left ventricular hypertrophy: a videodensitometric study

Myocardial texture analysis of two-dimensional echocardiographic gray level distribution is abnormal in hypertensive patients with severe increase of left ventricular mass. The aim of this study was to investigate the behavior of this parameter in hypertensive patients with absent-to-moderate left ventricular hypertrophy, more representative of the overall hypertensive population. We compared male essential hypertensive patients, with absent or mild-to-moderate left ventricular hypertrophy, with normotensive sedentary healthy subjects as controls. The groups (n = 18 each) were age- (+/- 2 years) and sex-matched. All subjects performed ambulatory blood pressure measurements for the evaluation of 24 h mean systolic and diastolic blood pressure. Quantitative analysis of echocardiographic digitized imaging was performed through a calibrated 256 gray level digitization system to calculate midseptum and midposterior end-diastolic and end-systolic first and second order textural analysis. In particular were observed the mean gray level cyclic variations to deriving the cyclic variation index (CVI). The hypertensives showed a significantly lower CVI compared with controls both for septum (P < .001) and for posterior wall (P < .0001). No significant relationships were found between CVI and relative diastolic thickness both of septum and posterior wall. Conversely, a significant inverse relationship was found between systolic arterial pressure values and CVI both of septum and posterior wall. Abnormalities of two dimensional echocardiographic gray level distribution are present also in hypertensive patients with absent or with mild-to-moderate levels of left ventricular hypertrophy, but seem unrelated to the degree of echocardiographic hypertrophy as such. Changes in collagen network distribution or microcirculatory alterations, secondary to pressure-volume overload per se or to other complex humoral factors, could explain these abnormalities. Further work is needed to establish the clinical, therapeutic, and prognostic implications of these findings.

On the contribution of biomedical engineering and technology to the understanding and the management of arterial hypertension

There are several reasons why arterial blood pressure, i.e. the pressure within the large arterial vessels, is out of the physical parameters of the human body, one of the most frequently measured. Firstly, arterial blood pressure is a physiologically meaningful parameter, since it represents the driving pressure generated by the heart which maintains blood perfusion in the periphery. Secondly, it is a clinically important parameter: a decline of arterial blood pressure (e.g. in shock) may represent a life-threatening emergency which requires prompt recognition and correction; elevated blood pressure (hypertension) on the other hand is a very common condition, which bears a high risk of cardiovascular mortality and morbidity and can be controlled with appropriate pharmacological means. Thirdly, but not lastly, arterial blood pressure is easily measurable with a fair degree of accuracy by the standard manual sphygmomanometric method and, more recently, by non-invasive automatic techniques. This paper discusses some of the aspects related to arterial blood pressure measurement, in which, in the author's opinion, medical engineering and technology are expected to provide useful advancements. Two major areas will be considered. The first regards the methodologies for arterial blood pressure assessment; the second the identification and acquisition of information additional to blood pressure which would be helpful for a better understanding of blood pressure measurements and/or of risk profiling. For the purpose of this brief paper, we shall mainly use examples and reasonings from our own experience.

Changes in pain perception and pain-related somatosensory evoked potentials in humans produced by exposure to oscillating magnetic fields

Nociception has been reported to be influenced by exposure to magnetic fields (MFs). The aim of this study was to investigate the effects of 2 h exposure to weak, oscillating MFs on pain perception thresholds and on pain-related somatosensory evoked potentials (SEPs). In 11 healthy volunteers, pain perception thresholds and pain-related SEPs were assessed by intracutaneous electrical stimulation. After sham treatment, pain thresholds significantly increased, whereas after MFs a slight non-significant decrease in thresholds was found. After both treatments pain-related SEP amplitude was reduced, but this decrease was more evident and statistically significant only after MF exposure. The increase found in thresholds after sham exposure may be due to stress-induced analgesia (SIA) and the contrasting behaviour recorded after MF exposure might indicate a suppression of SIA. The significant reduction in pain-related SEP amplitude observed after MF exposure provides the first evidence that human SEPs are influenced by MFs.

Further evidence for an endogenous digitalis-like compound in newborn and adult plasma detected by anti-ouabain antiserum

It is widely but not unanimously accepted that one or more endogenous digitalis-like factors (EDLF) circulate in human plasma. In this paper we provide confirmatory evidence that newborn plasma contains a factor with immunological and biological properties similar to ouabain and demonstrate that this factor may be present also in the adult. In fact, we obtained in newborn and adult plasma extracts, identical HPLC elution profiles of ouabain-like immunoreactivity and 86Rb erythrocyte uptake inhibitory activity with a major peak corresponding to the retention time of ouabain. The fact that immunoreactivity and biological digitalis-like activity in the peak are due to an identical substance is strongly supported by the correlation between RIA and 86Rb uptake inhibitory values observed in the purified fractions. Finally, the strong correlation between immunoreactivity observed in plasma samples after simple SepPak C18 extraction and after additional HPLC suggests that less purified samples may be assayed for screening purposes. However, for a more quantitative assessment, this simple extraction method needs a subsequent HPLC purification for eliminating an overestimation of values due to cross-reacting impurities.

Hypertension-associated hypalgesia. Evidence in experimental animals and humans, pathophysiological mechanisms, and potential clinical consequences

A behavioral hypalgesia (increased response threshold to noxious stimuli) has been consistently, although not invariably, reported in spontaneous and experimental acute and chronic hypertension in the rat. Studies in human hypertension have also demonstrated a diminished perception of pain, assessed as pain thresholds or ratings. The sensitivity to painful stimuli correlated inversely with blood pressure levels, and this relationship extended into the normotensive range. Evidence in humans and rats points to a role of the baroreflex system in modulating nociception. In the rat, blood pressure-related antinociception may be due to attenuated transmission of noxious stimuli at the spinal level secondary to descending inhibitory influences that are projected from brain stem sites involved in cardiovascular regulation and that may depend on baroreceptor activation and/ or on a central "drive." Both endorphinergic and noradrenergic central neurons (the latter acting through postsynaptic alpha 2-receptors) have been shown to be involved, and other mediators probably also play a role. Functionally, blood pressure-related antinociception may represent an aspect of a more-complex coordinated adaptive response of the body to "stressful" situations. It is still uncertain whether in human essential hypertension hypalgesia is secondary to elevated blood pressure or whether both depend on some common mechanism. Studies on the effect of hypotensive treatment are too few to allow conclusions. According to one hypothesis, the reduction in pain perception caused by baroreceptor activation secondary to blood pressure elevation may represent a rewarding mechanism that may be reinforced with repeated stress and may be involved in the development of hypertension in some individuals. Hypertension-associated hypalgesia may have clinically relevant consequences, especially in silent myocardial ischemia and unrecognized myocardial infarction, both of which are more prevalent in hypertensive individuals.

Evidence for an endogenous ouabain-like immunoreactive factor in human newborn plasma coeluted with ouabain on HPLC

The identification in human plasma of ouabain as an endogenous digitalis-like factor (EDLF) claimed by Hamlyn et al. has recently been contradicted by two studies which failed to demonstrate endogenous ouabain-like immunoreactivity in HPLC fractions in which exogenous ouabain was eluted. In this paper we report the results obtained on the cross-reactivity with antiouabain antibodies of an EDLF purified by us from human newborn cord plasma. We found that this EDLF coeluted with ouabain on HPLC and cross-reacted both with rabbit anti-ouabain antiserum and with the purified antibodies, which excluded possible interferences due to antibodies directed against non-ouabain portions of the immunogen. Similar but not identical slopes of the ouabain and EDLF displacements curves were observed in all competition ELISA experiments. The inhibitory effect of EDLF on erythrocyte 86Rb uptake was reversed by antiouabain antiserum and antibodies. The concentration of EDLF in newborn plasma, in the four different purifications studied ranged from 30 to 380 pM ouabain equivalents (o.e.) by ELISA and from 100 to 300 pM o.e. by 86Rb uptake. Our data thus support the existence, in human newborn plasma, of a factor with both biological and immunological ouabain-like properties, although not necessarily identical to ouabain.

The stimulatory effect on human erythrocyte rubidium-86 uptake by anti-cardiac-glycoside antibodies

Considerable, but as yet still controversial evidence indicates the presence, in mammalian tissues of endogenous digitalis-like factors (EDLFs) which inhibit cell membrane Na+, K(+)-adenosine triphosphatase (Na+, K(+)-ATPase) and which may cross-react with anti-digitalis antibodies. The aim of this study was to evaluate the effect of antibodies against cardiac glycosides on Na+, K(+)-ATPase in human erythrocytes. For this purpose, we measured the effect of antibodies against two different cardiac glycosides (anti-ouabain rabbit antiserum and anti-digoxin Fab fragments) on the activity of the Na+, K(+)-ATPase, as measured by erythrocyte rubidium-86 (86Rb) uptake, in subjects who had never come into contact with exogenous cardiac glycosides, and compared these results with the effect of two control rabbit sera: a normal serum and an antiserum to a non-related antigen. Anti-ouabain rabbit antiserum and anti-digoxin Fab fragments induced a significantly greater percentage change in 86Rb uptake in the erythrocytes than the two control sera (ANOVA followed by multiple comparison by the Games-Howell test). The average percentage change was +11.8 +/- 16.3% (n = 19) (mean +/- SD) for anti-ouabain antiserum +10.8 +/- 15.6% (n = 23) for anti-digoxin Fab fragments, -1.68 +/- 11.2% (n = 11) for anti-rhGM-CSF antiserum, and -5.8 +/- 11.7 (n = 10) for normal control serum. In a subgroup of ten subjects in whom the 3 antisera were tested simultaneously, the stimulation of erythrocyte 86Rb uptake induced by the two antidigitalis antibodies correlated significantly (r = 0.906, p = 0.001, n = 10).(ABSTRACT TRUNCATED AT 250 WORDS)

Exposure to oscillating magnetic fields influences sensitivity to electrical stimuli. II. Experiments on humans

To assess the effect of a magnetic treatment on pain perception, we compared the sensory threshold in 18 healthy volunteers. We determined the threshold by noninvasive electrical stimulation of the tooth pulp and skin before and after exposure to an altered magnetic field of low intensity and to a sham treatment. Five different parameters were recorded: the sensory and pain thresholds for the tooth and the sensory, pain, and tolerance thresholds for the skin. Two hours of exposure to a weak, oscillating magnetic fields induced a significant decrease in three parameters (dental sensory and cutaneous pain and tolerance thresholds), whereas the other two parameters showed a similar tendency. When the same subjects were exposed to a sham treatment, only marginal, nonsignificant variations in all parameters were observed. These results represent the first piece of evidence that weak alterations of the magnetic field may induce hyperalgesia in humans.

Exposure to oscillating magnetic fields influences sensitivity to electrical stimuli. I. Experiments on pigeons

The comparison of two measurements of the pigeon threshold for electrical stimuli, performed 2 h apart, reveals stress-induced analgesia as a result of stressful manipulations between the two tests. When pigeons are exposed to a weak, oscillating magnetic field between the two measurements, the analgesic response is inhibited and a hyperalgesic effect is recorded. The present findings are in agreement with previous studies showing that magnetic treatments may alter pigeons' emotional state and some of their behavioral patterns.

Insulin resistance and vasodilation in essential hypertension. Studies with adenosine

Insulin-mediated vasodilation has been proposed as a determinant of in vivo insulin sensitivity. We tested whether sustained vasodilation with adenosine could overcome the muscle insulin resistance present in mildly overweight patients with essential hypertension. Using the forearm technique, we measured the response to a 40-min local intraarterial infusion of adenosine given under fasting conditions (n = 6) or superimposed on a euglycemic insulin clamp (n = 8). In the fasting state, adenosine-induced vasodilation (forearm blood flow from 2.6 +/- 0.6 to 6.0 +/- 1.2 ml min-1dl-1, P < 0.001) was associated with a 45% rise in muscle oxygen consumption (5.9 +/- 1.0 vs 8.6 +/- 1.7 mumol min-1dl-1, P < 0.05), and a doubling of forearm glucose uptake (0.47 +/- 0.15 to 1.01 +/- 0.28 mumol min-1dl-1, P < 0.05). The latter effect remained significant also when expressed as a ratio to concomitant oxygen balance (0.08 +/- 0.03 vs 0.13 +/- 0.04 mumol mumol-1, P < 0.05), whereas for all other metabolites (lactate, pyruvate, FFA, glycerol, citrate, and beta-hydroxybutyrate) this ratio remained unchanged. During euglycemic hyperinsulinemia, whole-body glucose disposal was stimulated (to 19 +/- 3 mumol min-1kg-1), but forearm blood flow did not increase significantly above baseline (2.9 +/- 0.2 vs 3.1 +/- 0.2 ml min-1dl-1, P = NS). Forearm oxygen balance increased (by 30%, P < 0.05) and forearm glucose uptake rose fourfold (from 0.5 to 2.3 mumol min-1dl-1, P < 0.05). Superimposing an adenosine infusion into one forearm resulted in a 100% increase in blood flow (from 2.9 +/- 0.2 to 6.1 +/- 0.9 ml min-1dl-1, P < 0.001); there was, however, no further stimulation of oxygen or glucose uptake compared with the control forearm. During the clamp, the ratio of glucose to oxygen uptake was similar in the control and in the infused forearms (0.27 +/- 0.11 and 0.23 +/- 0.09, respectively), and was not altered by adenosine (0.31 +/- 0.9 and 0.29 +/- 0.10). We conclude that in insulin-re15-76sistant patients with hypertension, adenosine-induced vasodilation recruits oxidative muscle tissues and exerts a modest, direct metabolic effect to promote muscle glucose uptake in the fasting state. Despite these effects, however, adenosine does not overcome muscle insulin resistance.

Diastolic function in the different patterns of left ventricular adaptation to essential hypertension

Recent reports have shown that four distinct left ventricular anatomical patterns, with different hypertension severity and hemodynamic features, are associated with sustained arterial hypertension (normal anatomy, concentric remodeling, concentric hypertrophy and eccentric hypertrophy). The aim of this study was to evaluate left ventricular diastolic function in these different left ventricular anatomic patterns. To achieve this aim, 94 borderline-to-severe essential hypertensive patients (60 never treated before, 34 off treatment for at least 3 weeks before the study) underwent an echo-Doppler study; left ventricular thickness, dimension and mass index were obtained. Early (E) and late (A) transmitral flow velocity, their ratio (A/E) and the early filling fraction (EFF) were obtained by pulsed-wave Doppler and used as left ventricular diastolic function indexes. Differences between groups were evaluated by one-way ANOVA followed by Scheffe F-test. A normal left ventricular anatomy was found in 41 (44%), concentric remodeling in 17 (18%), concentric hypertrophy in 21 (22%) and eccentric hypertrophy in 15 (16%) patients. Early filling fraction and A/E ratio which resulted were significantly different for the groups (P < 0.001 and P < 0.002, respectively). As compared with the group with normal left ventricle, patients with concentric hypertrophy had significantly EFF and those with eccentric hypertrophy had significantly lower EFF and higher A/E ratio. Our results thus confirm the presence of distinct anatomical left ventricular adaptation patterns in arterial hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship between increased blood pressure and hypoalgesia: additional evidence for the existence of an abnormality of pain perception in arterial hypertension in humans

An association between hypertension and decreased pain perception (hypoalgesia) has been shown in experimental hypertension and confirmed in humans by electrical tooth pulp stimulation. The aim of this study was to confirm, using two other techniques, whether hypertension is associated with hypoalgesia in humans. In 77 untreated essential hypertensive outpatients, 37 normotensive outpatients and 27 normotensive volunteers subjective cutaneous sensitivity was assessed by an electrical stimulator. Thirty-three measurements were repeated after one month. In addition, in eight normotensive volunteers and eight hypertensives the thresholds of the polysynaptic components R2 and R3 of the blink reflex to electrical stimulation of the supraorbitalis nerve were evaluated. Tooth pulp stimulation was done in 85 of the subjects who measured cutaneous sensitivity and in all of the blink reflex study. Cutaneous perceptive, pain and tolerance thresholds were significantly higher in the hypertensives compared with both normotensive groups, with no significant difference between these two. The results were identical when age and sex-matched subgroups were compared and a high reproducibility was found for all three parameters. Similar findings were obtained for the tooth pulp thresholds and highly statistically significant correlations were found between cutaneous and tooth pulp sensitivity and between these indices and blood pressure. The thresholds of R2 and R3 were also significantly higher in the hypertensives and a significant correlation was found between R3 threshold and diastolic pressure. These results confirm that hypertension is associated to hypoalgesia in humans.

Echo Doppler diastolic function and exercise tolerance

OBJECTIVE

To investigate the possible association between Doppler left ventricular filling pattern and exercise capacity in a group of normotensives to severe hypertensive patients.

BACKGROUND

Invasive left ventricular filling indexes evaluated at rest are reported to be related to exercise capacity in heart failure. Whether exercise capacity is limited by abnormalities of left ventricular filling also in other less severe conditions is however unclear.

METHODS

Fifty-one subjects with normal to severely elevated blood pressure underwent a standard exercise test on cycle ergometer, negative for myocardial ischemia, and a complete echo Doppler evaluation showing a basal systolic function within normal limits.

RESULTS

Basal systolic function indexes were not significantly related to exercise duration. On the contrary, exercise duration was highly significantly correlated to the relative atrial contribution to left ventricular filling (0.001 < P < 0.05), in both the overall group and the two subgroups in whom exercise was interrupted because of fatigue (n = 30) or because of attaining target heart rate (n = 21). Significant correlations were also observed between exercise time and resting blood pressure, whereas no association with resting heart rate, age and body surface area was found. Exercise time also correlated to left ventricular mass and mass index but not to left ventricular volume. Multiple regression analysis showed that exercise tolerance was significantly related to diastolic blood pressure and left ventricular filling. Echo Doppler indexes of left ventricular filling are associated with exercise duration; left ventricular diastole could thus influence effort tolerance, not only in patients with cardiac insufficiency, but also in subjects with normal to elevated blood pressure levels and normal systolic function at rest.

Cardiac morphology and function in arterial hypertension. The effects of a new multifactorial hypotensive agent: urapidil

It has been recognized as increasingly important to determine whether antihypertensive agents, while satisfactorily lowering the blood pressure, at the same time adversely or positively affect the cardiac hemodynamic profile. On theoretical grounds, one would expect that an ideal hypotensive drug should decrease blood pressure by decreasing total peripheral resistances, without affecting cardiac output, and should normalize left ventricular hypertrophy without deteriorating systolic or diastolic left ventricular function. We here briefly review the effects of urapidil on these variables in patients under chronic treatment investigated in a series of studies employing echocardiography. The results of the studies are in fair agreement and indicate a blood pressure decrease already after one month of treatment, due to a decrease of peripheral resistances, without changes in heart rate. A clear trend towards a reduction of cardiac hypertrophy during the treatment is suggested by the significant decrements of the indices measured. One study also suggests that right ventricular wall thickness may be reduced. Left ventricular dimensions remained unchanged in all except one study. Systolic and diastolic function indices were also unchanged during the first 6 months of treatment and, in one study, improvement was found after 12 months of treatment. Taken together these results suggest that urapidil lowers blood pressure favorably, affecting cardiac morphology and function.

Captopril radionuclide test in renovascular hypertension: a European multicentre study. European Multicentre Study Group

The diagnostic work-up of renovascular hypertension is still controversial. The efficacy of renal scintigraphy with technetium-99m diethylene triamine pentaacetate (DTPA) before and after captopril (scintigraphic captopril test) was evaluated in a multicentre study. All 380 hypertensive patients in the study underwent renal arteriography; 125 had renal arterial stenosis > or = 70%, and 54 had a technically successful intervention to correct the stenosis. The post-captopril study had a sensitivity of 93% and a specificity of 100% for predicting blood pressure response to intervention, if renal function was normal and a combination of quantitative parameters was applied (individual kidney uptake index < 40%, time to peak activity < 2 min or > 10 min). In the entire population renal artery stenosis > or = 70% was detected with a sensitivity of 83% and a specificity of 93% if renal function was normal. In patients with abnormal renal function the performance of the test was worse, owing to a lower specificity which could be increased by using only time parameters. The performance of the test was optimal when the post-captopril findings were examined; no improvement was achieved by evaluation of the changes induced by captopril from the baseline. The test can thus be simplified by performing only a post-captopril study for routine use: a negative test would exclude a curable form of renovascular hypertension in > 80% and a positive test would predict it in > 90% of the patients selected for suspicion of the disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Endogenous digitalis-like activity in the newborn

Elevated levels of endogenous digoxin-like immunoreactivity have been reported in the body fluids of premature and full-term infants as well as in term pregnancy, in the amniotic fluid, and in human milk. Several lines of evidence suggest that these factors could also have biological properties in common with digitalis: i.e., they could represent truly endogenous digitalis-like factor(s). In recent years we succeeded in partially purifying this factor from umbilical cord blood, which represents an easily available source of this factor. The inhibitory activity of this factor on 86Rb uptake could be neutralized by antidigoxin antibodies (Fab fragments) and provided, for the first time, direct evidence of an association between digoxin-like immunoreactivity and biological digitalis-like activity. In addition, these antibodies could be used for immunoaffine chromatography as a purification step before separation by high-performance liquid chromatography. Preliminary experiments suggest that this endogenous compound has both a tissue and an isoenzyme selectivity and is not a well-known steroid (testosterone, progesterone, 17-OH progesterone, cortisol, dehydroepiandrosterone sulfate, and estradiol).