Impacts of Remote Physical Exercises on Functional Status and Mobility among Community-Dwelling Pre-Disabled Seniors during the Covid-19 Lockdown

OBJECTIVES

To assess whether remote physical exercise interventions helped maintain function in daily life, level of physical activities, basic mobility and frailty status in pre-disabled seniors during the first Covid-19 lockdown.

DESIGN

This is an interventional study conducted from May 2020 to May 2021.

SETTING

Community-dwelling older adults in 2 Canadian cities.

PARTICIPANTS

84 pre-disabled seniors.

INTERVENTION

12-week physical exercise programs (1 hour/ 3 times/ week) in kinesiologist-guided groups using Zoom or phone-supervised individual booklet-based home-program (n=44) vs. Control (usual life habits; n=40).

MEASUREMENTS

Functional status in daily activities (OARS scale); Daily level of aerobic (TAPA-1) and strengthening/flexibility (TAPA-2) physical activities; Basic mobility abilities (SPPB: balance, lower limbs strength, walking speed; Timed Up-and-Go) and Frailty (SOF index) were assessed at baseline and at 3, 6, 9 and 12-month follow-ups.

RESULTS

The participants' mean age was 78.5 ± 7.2 and 76.5 % were women. There was a group * time effect for the OARS scale (p=0.02), the TAPA-1 (p=0.06) and the TAPA-2 (p=0.007) scores. For these outcomes, scores significantly improved during the first 3 months of follow-up and then stabilised in the intervention group whereas they remained constant in the control group over time. There was an overall time effect for the SPPB (p=0.004), the 4-m walking speed (p=0.02) and for the SOF index (p=0.004), with no between-group differences. Finally, no effect was observed for the TUG.

CONCLUSION

Remote home-based physical exercise interventions and monitoring during the first Covid-19 lockdown seemed to have helped maintain seniors' level of physical activities without impacting on basic mobility abilities. Further studies are needed to identify parameters of remote exercise programs that can improve daily function and mobility in this population.

Feasibility and Acceptability of Remote Physical Exercise Programs to Prevent Mobility Loss in Pre-Disabled Older Adults during Isolation Periods Such as the COVID-19 Pandemic

This study aimed to assess the feasibility and acceptability of remote physical exercise (PE) to prevent mobility loss among pre-disabled older adults during the COVID-19 lockdowns. Participants followed a 12-week PE remote program in Zoom© supervised groups (Web-Ex group, n=11) or phone-supervised individual booklet-based home-program (Booklet group, n=33). The total rate of adherence was 82.5% in the Web-Ex group and 85.8% in the Booklet group. The level of satisfaction was « a lot » for 60% of the participants in the Web-ex group and for 37.9% of those included in the Booklet group. Respectively 10% and 31% of the participants rated the difficulty as « low » in the web-ex and Booklet groups. Remote physical exercise using a web technology or booklets at home with regular and personalized follow-up during the lockdown was feasible and acceptable among pre-disabled seniors.

A New Adaptive Home-based Exercise Technology among Older Adults Living in Nursing Home: A Pilot Study on Feasibility, Acceptability and Physical Performance

OBJECTIVES

To explore the feasibility and acceptability of a new home-based exercise technology among older adults and to evaluate its efficacy on physical performance measures.

DESIGN

Longitudinal clinical trial.

SETTING

Oak Hammock at the University of Florida, a nursing home located in Gainesville, Florida.

PARTICIPANTS

Twelve pre-disabled older adults (≥75 years) living in a nursing home with a Short Physical Performance Battery (SPPB) score between 6 and 9 and no diagnosis of dementia.

INTERVENTION

Thirty minutes of light intensity exercise (aerobic, strength and balance) two times per week for four weeks using a home-based physical activity technology called Jintronix.

MEASUREMENTS

Feasibility and acceptability were assessed through a 9-item self-administered questionnaire and by exploring the percentage of quality of movements and time performing exercise which was calculated automatically by Jintronix technology. Physical performance measures were assessed through the SPPB score at baseline, after 4 weeks of intervention and after 3 months from the completion of the intervention.

RESULTS

Twelve older adults (80.5±4.2 years old) performed light intensity exercise with Jintronix for a total of 51.9±7.9 minutes per week. Participants reached 87% score of quality of movements in strength and balance exercises, a global appreciation score of 91.7% and a global difficulty score of 36%. Compared to baseline, there was a significant improvement in SPPB score at the end of the intervention and at 3 months following the completion of the exercise program (0.67±0.98 and 1.08±0.99 respectively, p-value <0.05).

CONCLUSION

Jintronix technology is feasible and acceptable among pre-disabled older adults without dementia living in nursing home and is beneficial in improving their physical performance.

Pertinent parameters in photo-generation of electrons: Comparative study of anatase-based nano-TiO2 suspensions

In the field of solar fuel cells, the development of efficient photo-converting semiconductors remains a major challenge. A rational analysis of experimental photocatalytic results obtained with material in colloïdal suspensions is needed to access fundamental knowledge required to improve the design and properties of new materials. In this study, a simple system electron donor/nano-TiO2 is considered and examined via spin scavenging electron paramagnetic resonance as well as a panel of analytical techniques (composition, optical spectroscopy and dynamic light scattering) for selected type of nano-TiO2. Independent variables (pH, electron donor concentration and TiO2 amount) have been varied and interdependent variables (aggregate size, aggregate surface vs. volume and acid/base groups distribution) are discussed. This work shows that reliable understanding involves thoughtful combination of interdependent parameters, whereas the specific surface area seems not a pertinent parameter. The conclusion emphasizes the difficulty to identify the key features of the mechanisms governing photocatalytic properties in nano-TiO2.

Lenalidomide for second-line treatment of advanced hepatocellular cancer (HCC): A Brown University Oncology Group phase II study

4098

Background: Lenalidomide inhibits fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF) and multiple tumor growth pathways. There is no standard of care for patients who progress after sorafenib. Therefore, we performed a phase II study to determine the activity of lenalidomide in second-line HCC therapy. Methods: Patients with advanced HCC who progressed on or were intolerant to sorafenib were eligible. Prior chemoembolization, RFA, or surgery were allowed. Eligibility criteria also included bilirubin <4 mg/dL, AST and ALT <5 times upper limit of normal, ECOG performance status 0-2, platelet count >60,000/mm3, absolute neutrophil count >1000/mm3, and creatinine <2mg/dL. Patients were treated with lenalidomide 25mg orally days 1-21 of a 28 day cycle until disease progression or unacceptable toxicities. The planned original sample size was 25 patients but when early activity was demonstrated the study was expanded to 40 patients. Results: The study has completed accrual of 40 patients. The median age was 60.5 years (17-88 years). Nineteen patients were Child-Pugh A, 16 patients were B, and 5 patients were C. Twenty four patients had extrahepatic disease. Preliminary data is available on the first 37 patients. One patient had grade 4 neutropenia. Grade 3 toxicities included ANC (n=2), fatigue (n=4), rash (n=2), arthritis (n=1), diarrhea (n=1), dehydration (n=2). One patient developed variceal bleeding which precipitated encephalopathy and death. Of the 32 patients with elevated baseline AFP, nine (28%) had a >50% reduction including one patient with a reduction in AFP from 56,900ng/ml to 5 ng/ml. Six of the first 37 patients (16%) had a radiographic partial response. Two patients achieved a complete response and have not progressed at 36 and 32 months. Conclusions: Lenalidomide can be administered to patients with advanced HCC and significant hepatic dysfunction. Promising, and in a small percentage of patients, dramatic and durable activity has been demonstrated. Investigations are underway to explore the mechanism of action of lenalidomide in HCC.

Immunomodulatory effects of probiotics in the intestinal tract

The intestinal microbiota is the largest source of microbial stimulation that exerts both harmful and beneficial effects on human health. The interaction between probiotic and enterocytes is the initiating event in immunomodulation and merits particular attention. The effects of probiotic is strain dependent and for each new probiotic strain, profiles of cytokines secreted by lymphocytes, enterocytes or dendritic cells that come in contact with the strain should be systematically established. To evaluate the effects of probiotics on the immune system, models that mimic the mucosa, and thus the physiological reality, should be preferred whenever it is possible. Then, the in vitro observed effects should be backed up by properly conducted randomized double bind clinical studies. More detailed studies are needed to determine the precise action mode of probiotics on both mucosal and systemic immunity.

[Bilateral lower limb compartment syndrome after lumbar schwannoma surgery in genupectoral position]

Lower limb compartment syndrome is an unusual complication of the genu-pectoral position in lumbar spine surgery. We report a case of compartment syndrome in a patient who was operated in the genu- pectoral position for lumbar schwannoma resection. Overweigth and long time surgery could be important predisposing factors. Early diagnosis and treatment are mandatory to prevent permanent neurological deficits and other possible complications.

A phase I/II study of oxaliplatin, docetaxel, and capecitabine in advanced carcinoma of the esophagus and stomach

14046

Background: The Brown University Oncology Group has attempted to modify the regimen of docetaxel, cisplatin and fluorouracil (DCF) to reduce toxicity, simplify administration and maintain efficacy. We have a completed a phase I/II study of weekly doxetaxel, carboplatin and capecitabine for patients with advanced esophagogastric cancer (Safran et al, Am J Clin Oncol, 2006). In this phase I study we have substituted oxaliplatin for carboplatin to determine the maximum tolerated dose (MTD) of weekly docetaxel and oxaliplatin with capecitabine. Methods: Patients with metastatic esophageal and gastric cancers received docetaxel and oxaliplatin on days 1 and 8 and capecitabine in divided doses, twice daily, on days 1–10, with each cycle repeated every 21 days. Patients were treated at 4 dose levels as shown in the table. Results: Fourteen patients have been enrolled. The median age was 58.5 years. Eight patients had esophageal cancer and six had gastric cancer. Grade 3/4 dose limiting toxicities (DLTs) of diarrhea, nausea, and febrile neutropenia occurred in three of four patients at dose level 3. An intermediate dose level was added (2A), reducing the capecitabine dose. Conclusion: Oxaliplatin 50 mg/m2 and docetaxel 35 mg/m2 day 1 and 8 with capecitabine 750 mg/m2 BID × 10 days in 21 day cycles may represent a promising, easily administered regimen for metastatic esophageal and gastric cancer. Enrollment continues at dose level 2A. [Table: see text]

[Table: see text]

Erlotinib and chemoradiation followed by maintenance erlotinib for locally advanced pancreatic cancer: a phase I study

OBJECTIVES

A phase I trial was conducted to determine the maximally tolerated dose of erlotinib with concurrent gemcitabine, paclitaxel, and radiation for patients with locally advanced pancreatic cancer and to gather preliminary data on maintenance erlotinib after chemoradiation.

METHODS

Patients received gemcitabine, 75 mg/m2, and paclitaxel, 40 mg/m, weekly for 6 weeks with 50.4 radiation to the primary tumor and draining lymph nodes with a 2- to 3-cm margin. Erlotinib was administered over 3-dose levels (50-100 mg/d) with chemoradiation then all patients received 150 mg/d maintenance until disease progression.

RESULTS

Seventeen patients were assessable for toxicity; 13 with locally advanced disease and 4 who had undergone resection but had positive margins. At erlotinib dosages > or =75 mg/d with chemoradiation the dose-limiting toxicities were diarrhea, dehydration, rash, myelosuppression, and small bowel stricture. Maintenance erlotinib, 150 mg/d, was well tolerated. The median survival of the 13 patients with locally advanced disease was 14.0 months and 6 of 13 (46%) had a partial response.

CONCLUSIONS

The maximum tolerated dose of erlotinib with gemcitabine, paclitaxel and concurrent radiation is 50 mg/d for patients with locally advanced pancreatic cancer. Full dose maintenance erlotinib is well tolerated. Promising preliminary activity and overall survival were demonstrated.

Hypoxemia modifies circulating and exudate neutrophil number and functional responses in carrageenin-induced pleurisy in the rat

To assess the effect of hypoxemia on the responses of polymorphonuclear neutrophils (PMN) during an inflammatory response, rats were maintained in a low F1O2 atmosphere (9% O2) or room air for 12 h before intrathoracic injection of carrageenin or intradermal injections of agonists. After 4 h, hypoxemic rats had 50% more circulating PMN in blood and 25% less PMN in pleural exudate, whereas the number of PMN in skin biopsies did not differ from controls. Following hypoxemia, basal adhesion of blood PMN to serum-coated plastic wells was unchanged, whereas fMLP-stimulated adhesion was 50% greater. In contrast, basal adhesion of exudate PMN was 72% greater. In hypoxemic rats, exudate PMN produced 64% more PMA-stimulated superoxide than blood PMN; furthermore, blood and exudate PMN produced 4.5- and 2-fold more LPS-stimulated nitric oxide than controls, respectively. These results show that a moderate level of hypoxemia may trigger mechanisms that will interfere with PMN emigration yet prime these cells for enhanced responses upon stimulation.

The in vivo effects of adrenocorticotropin and sodium restriction on the formation of the different species of steroidogenic acute regulatory protein in rat adrenal

We have studied the in vivo expression of steroidogenic acute regulatory protein (StAR) in adrenals of control, ACTH-treated, and Na+-restricted rats. Indirect immunofluorescence by microscopy revealed the presence of StAR in the zonae glomerulosa (ZG) and fasciculata-reticularis (ZFR). An increased signal was observed in the ZG and zona fasciculata, 5 h after ACTH injection; a few cells of the medulla were also positive. Immunogold electron microscopy showed that StAR was mainly located over mitochondria (MT). By immunoblotting, a major 29-kDa and other minor StAR bands migrating between 30 and 39 kDa were increased 5 h after ACTH treatment but remained unchanged after 1 h. By two-dimensional-PAGE, four StAR species were revealed in homogenates of control ZG, and their intensity was increased 5 h after ACTH treatment but not after 1 h. Also, additional acidic species were seen 5 h after treatment. Other bands with basic isoelectric point were revealed between 29 and 37 kDa. Analyses on whole gland MT and supernatant (SN) revealed four bands in the control SN and five in ACTH SN; the intensity of one band was increased, and that of another one was decreased, in SN of treated rats. ACTH treatment resulted in the localization of many low-isoelectric point StARs in MT. After two-dimensional-PAGE, differences were found in the mobility of some StAR species in the ZG between controls and Na+-restricted rats. In MT, four bands were revealed in the ZG preparations of Na+-restricted and two bands in controls. Four bands were revealed in the ZG SNs of control and Na+-restricted rats; an additional band was observed only in the SN of treated animals, whereas the intensity of another band decreased. Na+ restriction did not affect StAR in the ZFR. In conclusion, StAR was present in the rat adrenal cortex ZG and ZFR and was mainly located in MT. StAR expression was inducible in the ZG and the ZF by ACTH, resulting in the formation of many StAR acidic species; interestingly, such changes were detectable 5 h, but not 1 h, after ACTH administration, suggesting that steroidogenesis stimulation by StAR might occur mainly outside MT. Although less spectacular than for ACTH, Na+ restriction also affected StAR expression in the ZG but not in the ZFR, by increasing two mitochondrial and one SN species, implying that StAR is involved in the mechanism of action of Na+ restriction in promoting aldosterone formation. These results suggest that differential processing and/or changes in phosphorylation may occur in vivo upon ACTH treatment and Na+ restriction. We hypothesize that modification of a relatively small quantity of StAR, mainly located outside MT, is necessary to increase adrenal steroidogenesis challenged either by ACTH or Na+ restriction.

Influence of dietary sodium restriction on angiotensin II receptors in rat adrenals

We studied the distribution of angiotensin II (AII) receptors type 1 (AT1) and type 2 (AT2) and the effects of a low sodium intake on these two subtypes of receptors in male rat adrenals. Binding studies on adrenal slices, on cell membranes and on cell suspensions were performed using [125I]AII and specific analogs for AT1 (Losartan) and AT2 (PD 123319) receptors. The distribution of AT1 was also studied by immunofluorescence. Complementary approaches were necessary to reach our goal. Indeed, by autoradiography on adrenal slices, [125I]AII was shown to bind to the zona glomerulosa (ZG) and to the medulla (M). When coincubated with [125I]AII, PD 123319 displaced [125I]AII from the medulla and from the ZG, indicating the presence of AT2 receptors in both zones. Losartan partially displaced [125I]AII from the ZG, indicating the presence of AT1 receptors in that zone. Furthermore, the labeling intensity of the medulla (AT2 receptors) was much stronger in adrenal sections from rats kept on a low sodium regimen than from controls. Immunofluorescence microscopy revealed that AT1 receptors were located mainly in the ZG of control rats. After sodium restriction, AT1 receptors appeared to be uniformly distributed within an enlarged ZG; furthermore AT1 receptor-positive cells were found to a limited degree in the zona fasciculata and possibly in the zona reticularis, and a greater number of these positive cells appeared in these zones under sodium restriction. Cell suspensions from rats fed a low sodium diet showed a 2.7- and 2.1-fold increase in total AII receptors in adrenal ZG and ZFR + M cells when compared with controls. Based on Losartan displacement, we calculated that [125I]AII bound to AT1 and to AT2 receptors was increased in both ZG and ZFR + M cell preparations under sodium restriction. Results of binding studies on cell membranes were also indicative of an increasing effect of sodium restriction on AT1 and AT2 receptors binding capacity. Furthermore, Northern blotting analysis revealed 3.0- and 2.5-fold increases in the level of AT1 receptor mRNA in the ZG and the ZFR + M of rats fed a low sodium diet as compared with those fed a normal diet. The low sodium intake resulted in a weaker increase (1.5-fold) in the level of AT2 receptor messenger RNA in the ZG, with no changes in the ZFR + M preparations. In conclusion, in this study complementary approaches were needed to determine the localization of AT1 and AT2 receptors in the rat adrenal, and to show the increasing effects of a low sodium regimen on the adrenal level of these receptors. Immunofluorescence studies revealed AT1 receptors mainly in the ZG and also in some cells of the inner adrenal cortex zones; in adrenals of rats kept on a low sodium diet the ZG was markedly enlarged, and an increased number of immunoreactive cells with AT1 receptors were observed throughout that zone; also more immunoreactive cells were present in the inner zones of the adrenal cortex. Furthermore in the adrenals of rats kept on a low sodium diet, we observed: 1) an increased number of AT1 and AT2 receptors in cell suspensions from the ZG, and in cell suspensions of the ZFR + M; 2) an increased level of AT1 and AT2 receptor mRNAs in the ZG; 3) an increased level of AT1 receptor mRNA, with no changes in the AT2 mRNA level in the ZFR + M. These results suggest a role for AT1 as well as for AT2 receptors in controlling adrenal function and differentiation under normal as well as under physiological stimulation of AII production following sodium restriction.

Immunolocalization and biochemical determination of cytochrome P450C17 in adrenals of hamsters treated with ACTH

We used an anti-rat adrenal cytochrome P450C17 (P450C17) antibody to perform immunofluorescence and also immunogold electron microscopic studies to determine the zonal and intracellular distribution of P450C17 in hamster adrenals. Because P450C17 activity is regulated mainly by adrenocorticotropin (ACTH), its zonal and intracellular localization was also analyzed after ACTH treatment. The effect of ACTH treatment on protein concentration was also investigated by Western blotting analysis. By immunofluorescence, we found P450C17 to be confined to the zona fasciculata (ZF) in the hamster, in contrast to other small rodents, which do not express P450C17 in their adrenals. After treatment with ACTH, the thickness of the ZF remained unchanged compared to that of control animals, whereas a marked increase in fluorescence intensity was observed. In addition, dispersed cells in the zona reticularis (ZR) showed positive staining after ACTH treatment. Immunocytochemistry with colloidal gold showed P450C17 to be localized and importantly increased only in the cytoplasmic areas between the mitochondria of ZF cells of ACTH-treated animals. These areas are predominantly occupied by elements of the endoplasmic reticulum and other unidentified organelles. Immunoblotting analysis of whole glands revealed a single protein band at approximately 55 kD, which reacted with the 450C17 antibody. After stimulation with ACTH injected at 5-hr intervals over a period of 20 hr, P450C17 protein concentrations were considerably greater than in control animals. In conclusion, P450C17 is located not over mitochondria but probably in the endoplasmic reticulum of the ZF cells in hamster adrenals. Treatment with ACTH induced expression of cytochrome P450C17 in ZF cells, increasing its production in these cells without stimulating cell proliferation.

Pharmacokinetics and pharmacodynamics of remifentanil in persons with renal failure compared with healthy volunteers

BACKGROUND

Remifentanil is an opioid analgesic for use in anesthesia. An ester linkage renders it susceptible to rapid metabolism by blood and tissue esterases. Thus it was hypothesized that remifentanil elimination would be independent of renal function. Because its principal metabolite (GR90291) is eliminated renally, it would depend on renal function. This study was designed to evaluate the pharmacokinetics and pharmacodynamics of remifentanil and its metabolite in persons with and without renal failure.

METHODS

Two groups of volunteers received two-stage infusions of remifentanil: low dose with 0.0125 microg x kg(-1) x min(-1) for 1 h followed by 0.025 microg x kg(-1) x min(-1) for 3 h; and high dose with 0.025 microg x kg(-1) x min(-1) for 1 h followed by 0.05 microg x kg(-1) x min(-1) for 3 h. Blood samples were collected for analysis of remifentanil and GR90291 concentrations. The pharmacokinetics of remifentanil were fit using a one-compartment pharmacokinetic model. Remifentanil's effect was determined intermittently using minute ventilation during a hypercapnic (7.5% CO2) challenge.

RESULTS

Fifteen patients with renal failure and eight control participants were enrolled. The clearance and volume of distribution of remifentanil were not different between those with renal failure and the controls. Patients with renal failure showed a marked reduction in the elimination of GR90291; the half-life of the metabolite increased from 1.5 h in the controls to more than 26 h in patients with renal failure. The steady-state concentration of GR90291 is likely to be more than 25 times higher in persons with renal failure. There were no obvious differences in opioid effects on minute ventilation in the controls and in patients with renal failure.

CONCLUSIONS

The pharmacokinetics and pharmacodynamics of remifentanil were not altered in patients with renal disease, but the elimination of its principal metabolite, GR90291, was markedly reduced. Based on simulations, the concentration of GR90291 at the end of a 12-h remifentanil infusion of 2 microg x kg(-1) x min(-1) is not likely to produce significant opioid effects.

Some effects of a low sodium intake on the expression of P450 aldosterone synthase in the hamster adrenal cortex: immunoblotting, immunofluorescent and immuno-gold electron microscopic studies

In the current work we studied the effects of a low sodium intake on P450 aldosterone synthase (P450aldo) in the adrenal cortex of male hamsters by Western blotting analysis. We also investigated the zonal distribution of P450aldo with a specific antibody using immunofluorescence and immuno-gold electron microscopy. Western blotting analysis revealed a progressive induction of P450aldo in the adrenals of hamsters kept on a low sodium diet, with two-, four- and eightfold increases after 2, 4 and 21 days on the diet. Immunofluorescence microscopy showed that P450aldo was confined to the zona glomerulosa (ZG) cells. Electron microscopy showed P450aldo to be located in the mitochondria of ZG cells. When hamsters were maintained on a low sodium intake for 2, 11 and 21 days, P450aldo was still found only in the ZG; the ZG appeared either unchanged or sometimes slightly enlarged. Moreover, at days 11 and 21, the intensity of the immunofluorescent signal was much stronger in the ZG of hamsters on the low sodium intake than in controls. Hence, immunocytochemistry using the colloidal-gold technique showed P450aldo to be more abundant in the mitochondria of the experimental animals than in controls. To conclude, P450aldo is present only in the ZG of hamster adrenals and sodium restriction appears to induce its expression by stimulating production within individual ZG cells rather than by stimulating a proliferation of the ZG cells.

P450aldo in hamster adrenal cortex: immunofluorescent and immuno-gold electron microscopic studies

The zonal distribution of aldosterone synthase cytochrome P450 (P450aldo) in the adrenal cortex of male hamsters was investigated by immunofluorescence and electron microscopy, using an anti-P450aldo peptide antibody. On cryostat sections the immunolocalization of P450aldo was confined to the zona glomerulosa cells. On semi-thin plastic sections, P450aldo was shown to be located in mitochondria. Studies in electron microscopy, using the colloidal gold technique, confirmed that P450aldo was located in mitochondria.

Physiological oestradiol and progesterone replacement cycles in women with ovarian failure: a model to study endometrial maturation and sex steroid receptor regulation by exogenous hormones

High endometrial receptivity has been achieved with physiological oestradiol and progesterone replacement cycles in women with ovarian failure. To understand whether different protocols using the oral route or the transdermal route can influence the endometrial maturation and the regulation of sex steroid receptors, we studied 33 women with ovarian failure treated by two commonly used protocols and assessed endometrial receptivity using light microscopy, scanning electron microscopy and immunohistochemistry for oestrogen and progesterone receptors on biopsies taken to include different periods of the luteal phase. The morphology in these patients was similar to that observed in women with normal ovulatory cycles, indicating that the morphological response is not dependent on the type of oestradiol, oral or transdermal, in the replacement cycles as compared to the endogenous oestradiol in the menstrual cycle. The relative distribution of steroid receptors between the epithelium and stroma varies similarly to that observed during the luteal phase of the menstrual cycle. These results confirm the role of progesterone, especially the importance of the number of days of exposure to it, in the disappearance of steroid receptors from endometrial glands. These observations give a better understanding of endometrial receptivity around the time of presumed implantation and confirm clinical results concerning the best timing of oocyte transfer.

[Major vascular complications following surgery for a herniated lumbar disk]

Two cases of arterial injury of the iliac arteries during surgery of the lumbar disc are presented. Both patients were successfully operated, in the first case a primary repair was accomplished, the second patient was treated by means of an ileo-femoral bypass graft. A comment of the pathophysiology, diagnostic and surgical management of this unusual complication is presented.

Biochemical appraisal of models for hepatic ischemia-reperfusion injury

Since total hepatic ischemia occurs with transplantation, there has been interest in developing a model which could be used to evaluate interventions to mitigate hepatic ischemic injury. The initial model employed global ischemia of the entire liver which necessitated the placement of a portal-femoral shunt (model A). In 1982, a model of hepatic ischemia was proposed in which ischemia was produced only in the left and median lobes which obviated the need for the shunt (model B). Recently, it has been found that with this model, increased flow to the nonischemic right lobe persists after left reperfusion thus effectively "stealing" blood from the reperfusing left lobe. Occlusion (model C) or removal (model D) of the right lobe on reperfusion have been proposed as techniques to reduce the "steal". We found, that after 30 min of ischemia, the ATP recovery for model B was significantly slower than for either model C or D. Similarly, the AMP content of model B lobes was significantly higher after 15 min of reperfusion, while 30 min after reperfusion, the total adenine nucleotide content was significantly lower in model B compared with models C and D. The energy charge returned to normal within 15 min of reperfusion in model C lobes while it was delayed until 60 min of reperfusion for models B and D. This study provides support for the advantages of right lobe occlusion (model C) over model B for acute studies evaluating the effect of interventions on ischemic injury to the liver and of removal (model D) for survival studies.

Hormonal dependence of pinopode formation at the uterine luminal surface

The uterine luminal epithelium during the period of receptivity for nidation displays characteristic protrusions of the apical surface named pinopodes. The effects of oestradiol and progesterone, singly or in combination, on the formation and regression of pinopodes were investigated using scanning electron microscopy. The appearance of pinopodes was found to be strictly progesterone dependent. When given together with progesterone, before the development of pinopodes, high doses of oestradiol (plasma level approximately 300 pmol/l) inhibited pinopode formation; on the contrary, low doses of oestradiol (nidatory doses) did not interfere with the process until the 4th day of treatment. When oestradiol was given as a single injection, after pinopode formation, both doses were equivalent in inducing their regression 48-72 h later. It appears that the hormonal conditioning for pinopode formation and for the development of uterine receptivity for egg implantation is the same. These observations support the hypothesis that pinopodes could be an extremely useful tool to estimate uterine receptivity. The experiments we describe here, together with observations made a few years ago, in stimulated cycles in the human, suggest that implantation failure as a result of a hormonal imbalance during the time intervening between ovulation and nidation, may be a general phenomenon.

Reversal of protamine-induced catastrophic pulmonary vasoconstriction by prostaglandin E1

A case of catastrophic pulmonary vasoconstriction occurring after cardiopulmonary bypass after protamine reversal of heparin treated successfully with intravenous prostaglandin E1 is reported. Systemic hypotension was counteracted by epinephrine given through the left atrium. Protamine-heparin reactions are reviewed and a pathophysiological mechanism for the beneficial effect seen with prostaglandin E1 is proposed.

Hormonal dependence of the metrial gland: further studies on oestradiol and progesterone receptor levels in the rat

The main objective of the present study was to analyse the hormonal dependence of the metrial gland formed in pseudopregnant animals following massive decidualization. On day 13 of pseudopregnancy (when the metrial gland reaches its maximal development) animals were ovariectomized and given s.c. implants of oestradiol and/or progesterone. A new implant technique for oestradiol delivery is described which provides circulating concentrations of oestradiol in the physiological range. In addition, we extended our previous work concerning oestradiol receptor and progesterone receptor concentrations in the metrial gland of pseudopregnant rats. The low oestradiol receptor concentration which we previously reported up to day 17 was maintained until the end of pseudopregnancy (day 21-1.5 fmol/micrograms DNA), whereas the progesterone receptor concentration remained raised (congruent to 3.5 fmol/micrograms DNA) from day 13 to day 19 and then decreased on day 21. The correlation of metrial gland weight and kinetics of the tissue oestradiol and progesterone receptors contents with the circulating oestradiol and progesterone concentrations lead to the following conclusions. First, the maintenance of the metrial gland is strictly progesterone-dependent. It is unlike the deciduoma which regresses spontaneously, even in the presence of progesterone. Secondly, the production of oestradiol receptor, but not of progesterone receptor, appears to be repressed in the metrial gland under the influence of progesterone. Thus, the tissue retains its ability to respond to progesterone because of a high concentration of progesterone receptor. It is difficult to attribute this high tissue progesterone receptor concentration to oestradiol stimulation since, even at low levels, oestradiol induces tissue regression. We suggest that the high progesterone receptor concentration could be due to constitutive (basal) progesterone receptor production.

Effect of mifepristone (RU 486) on concentrations of prostaglandin E-2 binding sites in the rat endometrium

Progesterone implants in ovariectomized rats increased endometrial concentrations of PGE-2 receptors. The increase was completely inhibited by simultaneous daily injection (7.5 mg/kg) of mifepristone (RU 486). A single injection of mifepristone on the morning of Day 1 of pseudopregnancy (day of oestrus) decreased the amount of PGE-2 receptors found in the endometrium on Day 5 by 64%. This inhibitory effect probably resulted from the antiprogesterone activity of this compound since it was not counteracted by simultaneous treatment with dexamethasone, shown to reverse totally the antiglucocorticoid action of mifepristone. The inhibition by mifepristone lasted only for 1 day; endometrial PGE-2 receptor levels on Day 6 of pseudopregnancy returned to the high values present in controls. Under these conditions, administration of the mifepristone did not affect the plasma oestradiol and progesterone concentrations during the 1st week of pseudopregnancy. The administration of mifepristone on Days 2 and 3 of pseudopregnancy kept the endometrial PGE-2 receptor levels low, even by 4 days after the end of treatment. We therefore concluded that, in the rat, progesterone priming leading to uterine receptivity can be delayed, at least by 1 day. In contrast, interruption of the progesterone action for a longer period later during the early pseudopregnant period resulted in an altered subsequent evolution of the endometrium, in terms of acquisition of the PGE-2 binding sites.

Scanning electron microscopy of postovulatory human endometrium in spontaneous cycles and cycles stimulated by hormone treatment

The ultrastructure of the luminal surface epithelium was compared in endometrial samples taken from 23 normally cycling women and from 22 patients submitted to ovarian stimulation with clomiphene citrate (100 mg/day for 5 days), human menopausal gonadotrophin (hMG) and human chorionic gonadotrophin (hCG). On day 2 after ovulation, only four out of nine specimens taken from the women in the hormone-treated group were identical to those of normally cycling women. On day 6 after ovulation, only two out of the 13 biopsy specimens from the treated group were the same as those from normally cycling women at that stage. Apical protrusions (pinopodes), typical for this period of the cycle, were missing in 11 of the 13 endometrial samples from the treated group. These observations suggest that the hormonal treatment applied to induce ovulation (clomiphene citrate, hMG and hCG) can modify the normal development of the prenidatory endometrium, and may thus have a negative effect on the rate of egg implantation.

Failure to detect specific binding sites for prostaglandin F-2 alpha in membrane preparations from rat endometrium

Membrane preparations from endometria of rats in different physiological states (e.g. pseudopregnancy, ovariectomized animals receiving progesterone + oestradiol or oestradiol alone) were studied for [3H]PGF-2 alpha binding by methods which detected PGF-2 alpha binding in ovary preparations and PGE binding in the same endometrial preparations. There was no evidence of high-affinity binding sites for [3H]PGF-2 alpha. Saturable [3H]PGF-2 alpha binding that increased with the onset of uterine sensitivity was detected but this binding does not fulfil all the criteria required for a PGF-2 alpha receptor and is probably due to binding to PG metabolizing enzymes in our preparations, or to binding of [3H]PGF-2 alpha to PGE binding sites. The failure to detect specific PGF-2 alpha binding sites seems to reflect a true absence of these sites in the rat endometrium.

Problems related to the implantation of the human egg after in vitro fertilization

Egg implantation, the process by which the conceptus comes in contact with the maternal vascular bed, occurs as the consequence of well coordinated ovo-endometrial interactions. In this paper the Authors describe the early steps of the implantation process in the rat. Several changes appearing in the rat endometrium are of particular interest because they also appear in the human endometrium around the normal time for implantation.

Estrogen and progesterone receptors in the endometrium, myometrium, and metrial gland of the rat during the decidualization process

Uterine cytosolic and nuclear receptors for estradiol (E2) and progesterone (P), were simultaneously determined in pseudopregnant rats subjected to a traumatic decidualizing stimulus (knife-scratch). The entire decidualizing endometrium, myometrium, and metrial gland were separated, homogenized, and studied on alternate days beginning with day 1 post trauma (pt) and extending to day 13 pt when even the metrial gland is regressing. The rise and fall in E2 and P receptors during the earlier stages of deciduoma differentiation confirmed the work of others. Splitting of the deciduoma on day 5 pt into antimesometrial and mesometrial segments showed a higher concentration of cytosolic P receptor in the well differentiated antimesometrial segment, whereas there was a higher concentration of E2 cytosolic receptor in the still differentiating mesometrial segment. The differences, measured as femtomoles per microgram DNA or per mg protein were statistically significant. The receptor changes in the myometrium were not as pronounced as in the endometrium especially with regard to the low myometrial levels of nuclear E2 and P. The metrial gland which comes into prominence while the deciduoma is regressing, showed sustained high concentrations of cytosolic P receptor. It is suggested that although initiated by the same decidualizing stimulus, the hormonal and receptor interplay in the metrial gland may be somewhat different from that of the deciduoma. The metrial gland merits further study because of an implied immunological role.

Endometrial prostaglandin E2 binding during the estrous cycle and its hormonal control in ovariectomized rats

Binding of [3H] prostaglandin E2 ([3H]PGE2) to endometrial membrane preparations obtained from rats at known stages of the estrous cycle and from ovariectomized rats treated with various combinations of progesterone and estradiol was determined. No specific, high-affinity binding of [3H]PGE2 could be detected by endometrial membrane preparations obtained throughout the estrous cycle. In ovariectomized rats treated with progesterone and estradiol to induce either the neutral, receptive or postreceptive phase of the endometrium for blastocyst implantation, the greatest concentration of endometrial PGE binding sites was found in the preparations from the neutral phase. Treatment of ovariectomized animals with estradiol and progesterone, alone or combined, revealed that endometrial PGE binding sites were progesterone-dependent, and were first detectable 48 h after the initiation of progesterone treatment. Following separation of the endometrial luminal epithelium and stroma in progesterone-treated ovariectomized rats, PGE binding sites were detected only in the stromal membrane preparation. The results indicate the endometrial PGE binding sites in the rat are under hormonal control and that no simple relationship exists between the concentration of endometrial binding sites and uterine sensitization for the decidual cell reaction.

Endometrial prostaglandin E2 binding: characterization in rats sensitized for the decidual cell reaction and changes during pseudopregnancy

As an initial step in testing the hypothesis that uterine receptivity for blastocyst implantation and sensitivity for decidualization are controlled in part by the presence of functional receptors for prostaglandin E2 (PGE2) in the endometrium, we have characterized the high-affinity binding of [3H]PGE2 to an endometrial membrane preparation from ovariectomized rats treated with progesterone and estradiol so that their uteri were sensitized for the decidual cell reaction. As determined by Scatchard analysis, a single class of [3H]PGE2 binding sites with an apparent Kd ranging from 2 to 6 nM and a capacity of approximately 100 fmol/mg protein was found. Prostaglandins E1 and E2 competed equally for binding while relative cross-reactivity of other prostanoids and compounds tested was less than 3%. Binding was temperature-dependent and reversible. Under the assay conditions used, no metabolism of [3H]PGE2 was detectable. Pretreatment of the membrane preparation with proteolytic enzymes, or by heating, reduced subsequent specific [3H]PGE2 binding. These data are consistent with the presence of endometrial PGE receptors in the sensitized endometrium. The binding of [3H]PGE2 to endometrial membrane preparations from rats on Days 2 to 7 pseudopregnancy was determined. No specific binding could be detected on Day 2. A low binding capacity was found on Days 3 and 4; this increased markedly on Day 5 and reached a maximum on Day 6. These data indicate that the onset of uterine receptivity/sensitivity is temporally correlated with the appearance of endometrial PGE binding sites.

Different responses of rat endometrial epithelium and stroma to induction of oestradiol binding sites by progesterone

Rats were ovariectomized for 3 weeks and then treated for 3 days with 4 mg progesterone. The cytosolic oestradiol receptor content in the stroma cells was very high (approximately 21,000 binding sites/cell) as compared with that in the epithelial cells (approximately 3000 binding sites/cell). The nuclear receptor values were low (approximately 500 binding sites/cell) in both types of cell.

Estrogen receptors in the nidatory sites of the rat endometrium

In ovariectomized rats treated with progesterone, implantation was induced by a minute dose of 17 beta-estradiol. Twenty-four hours later, the concentrations of estradiol receptor in nuclear and cytosol fractions prepared from the endometrium surrounding the blastocyst and the inter-implantation areas remained very low. This indicates that estrogen was not secreted by the blastocyst. The higher receptor content in cytosol from inter-implantation sites may reflect modifications accompanying the decidual reaction since our results show that there is no translocation of the receptor to the nuclei. The choice of the dye used to reveal the implantation sites is critical, since Trypan blue but not Evans blue binds steroids and thereby interferes with receptor measurements.

Nuclear receptor for oestrogen in the baboon endometrium: detection, characterization and variation in its concentration during the menstrual cycle

The present paper describes studies conducted to detect and characterize the nuclear receptor for oestrogen in the baboon endometrium. Only 10% of the [3H]oestradiol nuclear receptor complexes were extracted with a 0.5 M-KCl solution. This solubilized receptor migrated as a 4.4S peak during 5-20% sucrose gradient centrifugation. The oestrogen receptor was not bound to oestrogen in the nuclei under normal physiological conditions. Using an unlabelled competitor addition technique with intact nuclei the variation in oestrogen-receptor concentration of baboon endometrium during the menstrual cycle was measured. This concentration increased slightly during the first week of the cycle, being maximal on day 7 before ovulation (2500 molecules/cell), then decreasing gradually, reaching the lowest level (300 molecules/cell) on day 5 after ovulation, where it remained until the end of the cycle.

Oestrogen receptor in the baboon endometrium: cytosolic receptor, detection, characterization and variation of its concentration during the menstrual cycle

A cytosolic oestrogen receptor from baboon endometria was detected and partially characterized. The apparent dissociation constant for oestradiol was 1.5 x 10(-10)--4 x 10(-10) mol/l. Steroids that competed with the [3H]oestradiol binding to the receptor were oestradiol and ethynyloestradiol greater than oestriol greater than oestrone; progesterone, testosterone and corticosterone were not competitors. The [3H]oestradiol-receptor complexes migrated as a 3-3.5S peak during sucrose density-gradient centrifugation when endometrial samples were taken during either the proliferative or the secretory phase. A 7S peak was observed for samples taken at the period of ovulation. A [3H]oestradiol exchange technique was used to detect changes in the receptor concentration during the menstrual cycle. This concentration which was high during the early follicular phase fell sharply before the ovulatory peak of ovarian oestrogens. It remained at a base level during the early secretory phase and then rose during the last days of the cycle to the same concentration as that measured at the beginning of the cycle.

Progesterone-induced oestrogen receptors in the rat uterus

In ovariectomized rats progesterone acts like oestradiol at the endometrial, but not at the myometrial level, by increasing the number of oestrogen receptors in the cytoplasm. After 3 days of progesterone priming, the number of endometrial oestrogen receptors was found to be three times higher (P less than 0.05, Student's t-test) than control values. This progesterone-induced oestrogen receptor molecule appears identical in its physico-chemical properties (sedimentation coefficient, kinetic constants, steroid specificity) to that induced in the endometrium and myometrium under the influence of oestradiol. However, in the myometrium progesterone acts antagonistically reducing significantly (P less than 0.001, Student's t-test) the oestradiol-induced increase in the number of oestrogen receptors.

Endometrial content of nuclear estrogen receptor and receptivity for ovoimplantation in the rat

The purpose of this study was to provide information concerning the amount of nuclear binding sites for estrogen in endometrial cells during the first week of pregnancy in the rat. The "insoluble" (high-salt non-extractable) binding during the first four days of pregnancy follows a circadian rhythm, with a maximal value at midnight, and a minimal one a noon. By day 5, the amount plateaus at a minimal value. The number of estradiol binding sites of the soluble (high-salt extractable) nuclear fraction shows a similar pattern. All the necessary elements for the estrogen-dependent induction of endometrial receptivity for nidation appear, therefore, to be present already by day 3, but the turning on of the endometrial response to estrogen on day 4 seems to depend on additional factor(s).