Efficacy of controlvit as a complementary strategy in reducing hospitalizations in patients with heart failure. Randomized clinical trial

Introduction

In patients with heart failure, the main cause of hospital admissions is due to episodes of decompensation, which are associated with an increase in the costs and resources needed for care; they have a negative impact on the quality of life and prognosis of the disease. Therefore, it is necessary to design, evaluate and implement alternatives to achieve efficient follow-up and monitoring, improving adherence to treatment and helping identify decompensation episodes that facilitate their early treatment, so new hospital admissions can be avoided. For this reason, the use of information and communication technologies (apps) is emerging as an excellent strategy for the possibility of improving coverage, real-time monitoring and timeliness of care. ControlVit® is an electronic application that allows permanent, real-time monitoring of biomedical measurements for early detection of complications.

Objective

To determine the efficacy of ControlVit® as a complementary strategy in reducing hospital admissions in patients in a heart failure program.

Methodology

A randomized, placebo-controlled, open-label clinical trial was conducted, (n=140), included patients with heart failure under controlled clinical follow-up in a structured heart failure program, into NYHA FC II–IV, capable of handling smartphones and with permanent internet connectivity. All patients were provided with educational elements, a scale and a blood pressure monitor to enter clinical data and a symptom questionnaire necessary for follow-up. The patients were randomized to 2 groups: intervention: use of ControlVit® vs. placebo, with a 6-month follow-up. The primary outcome was the difference in readmissions for heart failure between the 2 groups. Patients on the waiting list for heart transplantation or use of ventricular assist devices were excluded. All participants signed informed consent and the protocol was approved by the institutional ethics committee.

Results

A total of 140 patients were included in the study (intervention = 71, placebo = 69), with an average age of 66 years, 71% were men, the main etiology of heart failure was ischemic (60%), the main comorbidities were arterial hypertension (44%), dyslipidemia (42%), hypothyroidism (38%), chronic kidney disease (38%), and diabetes mellitus (27%). During follow-up, there were 6 deaths (3 in each group) and 17 readmissions (3 in the intervention group and 14 in the control group). After adjustment for comorbidities, HR 0.72 CI95 (0.52; 0.92), p=0.0325 was found.

Conclusion

In patients with heart failure, ControlVit® is a useful and complementary tool for follow-up, which reduces hospital admissions due to episodes of decompensation.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): German Saldarriega award.Javeriana University

Effect of Different Wheat-Based Diets and Corn Meal Addition on Development Parameters of Ephestia kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae)

The expansion of Integrated Pest Management (IPM), including biological control, has had several positive consequences for the agricultural environment and participants in the production chain. To enable successful operation and applications of biological control, production of insects used for rearing natural enemies (parasitoids and predators) must be optimized to reduce time and costs and improve production both qualitatively and quantitatively. The present study evaluated the effect of wheat varieties, the main component of artificial diets for Ephestia kuehniella, on the reproductive performance and biological parameters of this flour moth, which is used for mass production of Trichogramma spp. (Hymenoptera: Trichogrammatidae) and other parasitoids and predators. Four varieties of wheat were compared: BRS 327, BRS Marcante, BRS Parrudo, and KBR, with and without the addition of corn E. kuehniella reared on 97% BRS 327 wheat flour + 3% nutritional yeast had the best biological parameters and substitution of corn for about half of the wheat increased the number of eggs per female.

Measurements meet perceptions: rheology-texture-sensory relations when using green, bio-derived emollients in cosmetic emulsions

OBJECTIVE

Product aesthetics and sensory performance can strongly influence a cosmetic product's acceptance by consumers. However, classic sensory analysis is time-consuming, expensive and does not provide information on the target group's preference. In the previous phase of this project, we had untrained consumers evaluate six cosmetic emulsions based on their aesthetics using a check-all-that-apply (CATA) survey. In this project, our goals were to quantitatively characterize the rheology and textural properties of the six cosmetic emulsions containing green, bio-derived emollients and identify statistical relationships between the consumers' description of products and the instrumental measurements.

METHODS

Six emulsions were prepared-three with olive oil and three with heptyl undecylenate as an emollient. Four sensory-like attributes, namely firmness, work of shear, stickiness and adhesiveness, were tested using a texture analyser. Rheological characterization included continuous flow testing and oscillatory measurements. Droplet size and stability were also evaluated. Statistical relationships were quantified between measurements in this study and sensory survey results published previously.

RESULTS

The textural and rheological results indicated that the emulsions were different-as designed. The texture and rheology measurements had analogous grouping outcomes to the consumers' discrimination. Emulsions 1 and 2 were the firmest, hardest to spread, stickiest and had the highest viscosity, while Emulsions 5 and 6 were the least firm, easiest to spread, less sticky than Emulsions 1 and 2, and had the lowest viscosity. Emulsions 3 and 4 fell in between the other two groups. Using olive oil instead of heptyl undecylenate as an emollient increased firmness, spreading, stickiness, viscosity and droplet size of the emulsions in every case-when comparing emulsions within each pair. All six emulsions had a shear-thinning behaviour. Viscosity and firmness directly correlated for the emulsions. Emulsions were visually stable at room temperature over the course of 6 months and viscosity remained relatively constant over this period also.

CONCLUSION

Certain sensory attributes can be reliably predicted with instrumental measurements. Identifying and quantifying sensory-texture-rheology relationships can contribute to achieving appropriate product characteristics tailored to suit market needs.

The Enemy is Outside: Releasing the Parasitoid Tamarixia radiata (Hymenoptera: Eulophidae) in External Sources of HLB Inocula to Control the Asian Citrus Psyllid Diaphorina citri (Hemiptera: Liviidae)

Huanglongbing (HLB), the most destructive citrus disease worldwide, was first recorded in Brazil in 2004, and since then, more than 50 million trees identified with this disease have been eliminated. The disease is managed mainly by controlling the psyllid vector Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae). Although the presence of the insect in commercial citrus groves is low, HLB infection rates increase in areas bordering the groves. The disease is transmitted by psyllids from host citrus plants in areas outside the managed groves, such as abandoned or organic groves and residential trees, and from orange jasmine plants in urban settings. In order to provide information to support HLB control, this study evaluated the biotic and abiotic variables that affect the dynamics of D. citri populations after releases of the parasitoid wasp Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) in external sources of HLB inocula. The study was divided into two parts. After releasing the parasitoids in non-commercial areas, we determined the following: (a) the variables that significantly affected the number of nymphs collected on shoots in the same non-commercial area; (b) the variables that significantly affected the number of adult psyllids collected in a neighboring commercial citrus area. Our results indicated that the number of nymphs in external areas was affected only by the host plant and rainfall. However, periodic parasitoid releases significantly reduced the number of adult psyllids collected in the commercial area. The results indicate that the release of parasitoids in external sources of inocula has the potential to maximize actions for D. citri control, contributing to the reduction of psyllid populations in commercial areas. Consequently, this strategy may help to manage the disease infection without an increase in insecticide use.

Delimiting Strategic Zones for the Development of Fall Armyworm (Lepidoptera: Noctuidae) on Corn in the State of Florida

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), cannot survive prolonged periods of freezing temperatures, thereby limiting where it can overwinter in North America. Climate change is anticipated to reduce the frequency of freeze days in Florida over the decades, with the potential consequence of a significant expansion of the overwintering range, whose northern limit in North America was assessed between 27 and 28°N in the last century. To assess this possibility, the development of the fall armyworm on corn leaves, one of the main host plants in the United States, was determined at five constant temperatures ranging from 14 to 30°C. Based on the development time, the thermal constant and the lower threshold temperature were used to estimate the number of generations of fall armyworm at 42 locations in the state of Florida, from 2006 to 2016. Maps were constructed to provide a visual description of the interpolated data, using GIS (Geographic Information System). The highest number of generations was observed in the counties farther south, an area that showed the highest temperatures during the years and plays a strategic role in maintaining fall armyworm populations in corn fields. Additionally, we conclude that in the absence of freeze periods, the northern limit for fall armyworm overwintering should be between 28 and 29°N.

Geostatistics and Geographic Information System to Analyze the Spatial Distribution of the Diversity of Anastrepha Species (Diptera: Tephritidae): the Effect of Forest Fragments in an Urban Area

Fruit flies are among the most damaging insect pests of commercial fruit in Brazil. It is important to understand the landscape elements that may favor these flies. In the present study, spatial data from surveys of species of Anastrepha Schiner (Diptera: Tephritidae) in an urban area with forest fragments were analyzed, using geostatistics and Geographic Information System (GIS) to map the diversity of insects and evaluate how the forest fragments drive the spatial patterns. The results indicated a high diversity of species associated with large fragments, and a trend toward lower diversity in the more urbanized area, as the fragment sizes decreased. We concluded that the diversity of Anastrepha species is directly and positively related to large and continuous forest fragments in urbanized areas, and that combining geostatistics and GIS is a promising method for use in insect-pest management and sampling involving fruit flies.

A Theoretical Approach to Analyze the Parametric Influence on Spatial Patterns of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) Populations

Studies of the influence of biological parameters on the spatial distribution of lepidopteran insects can provide useful information for managing agricultural pests, since the larvae of many species cause serious impacts on crops. Computational models to simulate the spatial dynamics of insect populations are increasingly used, because of their efficiency in representing insect movement. In this study, we used a cellular automata model to explore different patterns of population distribution of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), when the values of two biological parameters that are able to influence the spatial pattern (larval viability and adult longevity) are varied. We mapped the spatial patterns observed as the parameters varied. Additionally, by using population data for S. frugiperda obtained in different hosts under laboratory conditions, we were able to describe the expected spatial patterns occurring in corn, cotton, millet, and soybean crops based on the parameters varied. The results are discussed from the perspective of insect ecology and pest management. We concluded that computational approaches can be important tools to study the relationship between the biological parameters and spatial distributions of lepidopteran insect pests.

Endovascular reconstruction of internal carotid artery dissection in patients with acute ischemic stroke using the Wingspan stent

OBJECTIVE

The purpose of this study is to demonstrate our experience in endovascular reconstruction of carotid dissections using the Wingspan Stent System™ (Boston Scientific, Natick, MA, USA), a device we use because of its high radial force and its navigation in extreme curves.

METHODS

We treated 11 consecutive patients with acute ischemic stroke due to carotid dissection with the Wingspan stent, in the cervical carotid artery.

RESULTS

Functional evaluation revealed that 10 of the 11 patients were independent at 3 months post surgery and that the 11 stents used were found to be patent at the 6-month follow-up digital subtraction angiography (DSA).

CONCLUSIONS

The Wingspan stent is an alternative to classic carotid stents and flow diverters for the treatment of cervical internal carotid artery (ICA) dissection associated with ectasias or large loops. The device remains patent over the long term and it is not associated with arterial wall complications.

Histological changes in the rat brain and spinal cord following prolonged intracerebroventricular infusion of cerebrospinal fluid from amyotrophic lateral sclerosis patients are similar to those caused by the disease

INTRODUCTION

Cerebrospinal fluid (CSF) from amyotrophic lateral sclerosis (ALS) patients induces cytotoxic effects in in vitro cultured motor neurons.

MATERIAL AND METHODS

We selected CSF with previously reported cytotoxic effects from 32 ALS patients. Twenty-eight adult male rats were intracerebroventricularly implanted with osmotic mini-pumps and divided into 3 groups: 9 rats injected with CSF from non-ALS patients, 15 rats injected with cytotoxic ALS-CSF, and 4 rats injected with a physiological saline solution. CSF was intracerebroventricularly and continuously infused for periods of 20 or 43days after implantation. We conducted clinical assessments and electromyographic examinations, and histological analyses were conducted in rats euthanised 20, 45, and 82days after surgery.

RESULTS

Immunohistochemical studies revealed tissue damage with similar characteristics to those found in the sporadic forms of ALS, such as overexpression of cystatinC, transferrin, and TDP-43 protein in the cytoplasm. The earliest changes observed seemed to play a protective role due to the overexpression of peripherin, AKTpan, AKTphospho, and metallothioneins; this expression had diminished by the time we analysed rats euthanised on day 82, when an increase in apoptosis was observed. The first cellular changes identified were activated microglia followed by astrogliosis and overexpression of GFAP and S100B proteins.

CONCLUSION

Our data suggest that ALS could spread through CSF and that intracerebroventricular administration of cytotoxic ALS-CSF provokes changes similar to those found in sporadic forms of the disease.

Analysis of endovascular treatment of ruptured aneurysms of the middle cerebral artery compared to other anatomical locations

OBJECTIVE

The objective of this article is to compare the results of endovascular treatment of ruptured middle cerebral artery (MCA) aneurysms with ruptured aneurysms of other anatomic locations.

METHODS

Fifty consecutive ruptured aneurysms of the MCA and 209 aneurysms at other anatomical locations were selected retrospectively. We compared epidemiological, clinical and radiological variables, prognosis and complications.

RESULTS

The MCA aneurysms had a greater size and a poor dome/neck ratio. There were no significant differences in endovascular technique complications, occlusion rate or rebleeding between the two groups (p > 0.1). There were no significant differences in the mortality and number of dependent patients after one month.

CONCLUSION

The endovascular treatment of ruptured MCA aneurysms without hematoma is as safe and effective as other aneurysm localizations. Complication rates, occlusion rates and rebleeding of ruptured MCA aneurysms are comparable to other locations.

Anatomical results, rebleeding and factors that affect the degree of occlusion in ruptured cerebral aneurysms after endovascular therapy

OBJECT

To present a series of ruptured cerebral aneurysms in consecutive non-selected patients treated with endovascular therapy, analyzing the initial degree of occlusion, its anatomical evolution mid-term and the variables that could statistically affect them.

METHODS

251 aneurysms were first treated with coiling (embolization). 203 patients were followed up with conventional angiography for 6-8 months after the initial treatment and 182 were followed up with three-dimensional time of flight MR angiography at 18-24 months. Postoperative and mid-term anatomical results were evaluated anonymously and independently using the modified Montreal Scale.

RESULTS

The initial rate of complete occlusion was 70.9%, with rates of neck remnants and aneurysm remants of 18.3% and 10.7%, respectively. The recurrence rate was 13% after 6 months and 2% between 6 months and 2 years. The rate of retreatment was 11%. Statistically, the variables that were found to be related to the initial degree of occlusion were the use of a remodeling balloon technique (p=0.012), the size of the aneurysm neck (p=0.044) and the size of the aneurysm (p=0.004). The recanalization rate at mid-term depended on the size of the aneurysm. Although aneurysms with partial occlusion initially tended to evolve to a worse degree of closure than those with complete occlusion initially, the relationship was not statistically significant (p=0.110).

CONCLUSIONS

Embolized aneurysms can develop a worse degree of closure even when the initial occlusion is complete. The degree of occlusion depends directly on morphological factors and the use of balloon-assisted techniques. The recanalization rate at mid-term depends on the size of the aneurysm and probably on the density of the packing achieved with the initial treatment.

Alveolar distraction osteogenesis: a systematic review

This literature review was performed to analyse the outcomes of clinical studies of alveolar distraction osteogenesis (DO) listed by PUBMED between January 1996 and December 2006. A PUBMED search identified 128 articles on alveolar DO. Twenty articles covering 209 cases were analysed, considering location, device and procedural parameters, rate of augmentation, aspect of final implant placement and follow up. The mean latency period was 7.26+/-2.31 days, distraction rate 0.71+/-0.27 mm/day, rate of augmentation 6.88+/-2.52 mm and consolidation period 12.22+/-5.58 weeks. A total of 469 implants were placed and followed post loading for an average of 14.19+/-11.03 months, with a survival rate of 97%. Of the different procedural parameters, only the difference between mean consolidation period for failed (8.10+/-2.51 weeks) and successful (12.43+/-5.62 weeks) implants was statistically significant (P=0.01). Use of DO may be advantageous in terms of the success rate of implants placed in augmented sites, but there is still a lack of sufficient data based on long-term follow up. Future experimental studies should evaluate the application of different methods with a view to shortening the overall treatment period and improving the performance of implants placed in distracted alveolar ridges.

The comparative hemodynamic effects of intravenous IQB-9302 and bupivacaine in anesthetized rats

BACKGROUND

The new local anesthetic IQB-9302 is an amide derivative bearing a cyclopropyl group, with remarkable long duration of action and relative low toxicity. In trying to characterize further its safety profile, the current study compared the hemodynamic effects of different concentrations of bupivacaine and IQB-9302 with saline.

METHODS

Two groups of eight anesthetized Sprague-Dawley rats were given 0.1, 0.3, 1, 3, and 10 mg/kg of intravenous (i.v.) IQB-9302 or bupivacaine at 20-min intervals; control animals received saline only. Arterial blood pressure and heart rate were monitored during the following 20 min.

RESULTS

Both bupivacaine and IQB-9302 reduced heart rate: for bupivacaine, -73.8 beats per min (bpm) (SD: 103.8) and -132.5 bpm (SD: 140.7) at 1 and 3 mg/kg, respectively; for IQB-9302, the reduction amounted to -40.8 bpm (SD: 14.2) and -113.5 bpm (SD: 94.2) at 1 and 3 mg/kg, respectively (baseline range, 318.7-438.2 bpm). The two drugs also produced a comparable increase in the mean arterial blood pressure; bupivacaine increased it by 8.7 mmHg (SD: 6.6) and 12.6 mmHg (SD: 15.4) at 1 and 3 mg/kg, respectively, and IQB-9302, 18.7 mmHg (SD: 21.1) and 20.7 mmHg (SD: 20.5) at 1 and 3 mg/kg, respectively (baseline range, 47.4-134.1 mmHg). All rats treated with 10 mg/kg of either drug died after a drop in heart rate and mean arterial blood pressure.

CONCLUSION

IQB-9302 had hemodynamic effects similar to those of bupivacaine in anesthetized rats. The clinical relevance of these effects warrants further investigation.

Does oral contraceptive use affect the incidence of complications after extraction of a mandibular third molar?

OBJECTIVE

This study investigated whether oral contraceptive use affects the incidence of complications (pain, trismus, dry socket) in women undergoing removal of impacted mandibular third molars.

PATIENTS AND METHOD

Two hundred and sixty seven women, aged 17 - 45 years, underwent removal of an impacted mandibular third molar. Eighty seven of the women were regular users of oral contraceptives. All patients were evaluated for postoperative pain, trismus and dry socket (localized alveolar osteitis).

RESULTS

Mean trismus values (measured as maximum interincisal distance) were similar in the two groups of patients. Postoperative pain was significantly more frequent among women taking contraceptives, both on day 1 (30% of women taking contraceptives used analgesics, versus 11% of women not taking contraceptives, p < 0.001) and on day 5 (14% versus 5%, p = 0.024). Similarly, dry socket occurred more frequently among women taking contraceptives than among women not taking contraceptives (11% versus 4%, p = 0.017).

CONCLUSIONS

The results of this study support the view that oral contraceptive use favours the appearance of dry socket and postoperative pain after extraction, but has no effect on trismus.

Calcium-dependent inhibition of L, N, and P/Q Ca2+ channels in chromaffin cells: role of mitochondria

The hypothesis that the buffering of Ca(2+) by mitochondria could affect the Ca(2+)-dependent inhibition of voltage-activated Ca(2+) channels, (I(Ca)), was tested in voltage-clamped bovine adrenal chromaffin cells. The protonophore carbonyl cyanide m-chlorophenyl-hydrazone (CCCP), the blocker of the Ca(2+) uniporter ruthenium red (RR), and a combination of oligomycin plus rotenone were used to interfere with mitochondrial Ca(2+) buffering. In cells dialyzed with an EGTA-free solution, peak I(Ca) generated by 20 msec pulses to 0 or +10 mV, applied at 15 sec intervals, from a holding potential of -80 mV, decayed rapidly after superfusion of cells with 2 microm CCCP (tau = 16.7 +/- 3 sec; n = 8). In cells dialyzed with 14 mm EGTA, CCCP did not provoke I(Ca) loss. Cell dialysis with 4 microm ruthenium red or cell superfusion with oligomycin (3 microm) plus rotenone (4 microm) also accelerated the decay of I(Ca). After treatment with CCCP, decay of N- and P/Q-type Ca(2+) channel currents occurred faster than that of L-type Ca(2+) channel currents. These data are compatible with the idea that the elevation of the bulk cytosolic Ca(2+) concentration, [Ca(2+)](c), causes the inhibition of L- and N- as well as P/Q-type Ca(2+) channels expressed by bovine chromaffin cells. This [Ca(2+)](c) signal appears to be tightly regulated by rapid Ca(2+) uptake into mitochondria. Thus, it is plausible that mitochondria might efficiently regulate the activity of L, N, and P/Q Ca(2+) channels under physiological stimulation conditions of the cell.

The sea anemone toxin Bc2 induces continuous or transient exocytosis, in the presence of sustained levels of high cytosolic Ca2+ in chromaffin cells

We have isolated and characterized a new excitatory toxin from the venom of the sea anemone Bunodosoma caissarum, named Bc2. We investigated the mechanism of action of the toxin on Ca(2+)-regulated exocytosis in single bovine adrenal chromaffin cells, monitoring simultaneously fura-2 fluorescence measurements and electrochemical recordings using a carbon fiber microelectrode. Bc2 induced quantal release of catecholamines in a calcium-dependent manner. This release was associated with a sustained rise in cytosolic Ca(2+) and displayed two different patterns of response: a continuous discharge of prolonged duration that changed to a transient burst as the toxin concentration (or incubation time) increased. Continuous secretion was dependent on the activity of native voltage-dependent Ca(2+) channels and showed a pattern similar to that of alpha-latrotoxin; however, its kinetics adjusted better to that of continuous cell depolarization with high K(+) concentration. In contrast, transient secretion was independent of Ca(2+) entry through native voltage-dependent Ca(2+) channels and showed inhibition of late vesicle fusion that was accompanied by "freezing" of F-actin disassembly. These new features make Bc2 a promising new tool for studying the machinery of neurotransmitter release.

Synergism between toxin-gamma from Brazilian scorpion Tityus serrulatus and veratridine in chromaffin cells

Toxin-gamma (Tgamma) from the Brazilian scorpion Tityus serrulatus venom caused a concentration- and time-dependent increase in the release of norepinephrine and epinephrine from bovine adrenal medullary chromaffin cells. Tgamma was approximately 200-fold more potent than veratridine judged from EC50 values, although the maximal secretory efficacy of veratridine was 10-fold greater than that of Tgamma (1.2 vs. 12 microg/ml of catecholamine release). The combination of both toxins produced a synergistic effect that was particularly drastic at 5 mM extracellular Ca2+ concentration ([Ca2+]o), when 30 microM veratridine plus 0.45 microM Tgamma were used. Tgamma (0.45 microM) doubled the basal uptake of 45Ca2+, whereas veratridine (100 microM) tripled it. Again, a drastic synergism in enhancing Ca2+ entry was seen when Tgamma and veratridine were combined; this was particularly pronounced at 5 mM [Ca2+]o. Veratridine induced oscillations of cytosolic Ca2+ concentration ([Ca2+]i) in single fura 2-loaded cells without elevation of basal levels. In contrast, Tgamma elevated basal [Ca2+]i levels, causing only small oscillations. When added together, Tgamma and veratridine elevated the basal levels of [Ca2+]i without causing large oscillations. Tgamma shifted the current-voltage (I-V) curve for Na+ channel current to the left. The combination of Tgamma with veratridine increased the shift of the I-V curve to the left, resulting in a greater recruitment of Na+ channels at more hyperpolarizing potentials. This led to enhanced and more rapid accumulation of Na+ in the cell, causing cell depolarization, the opening of voltage-dependent Ca2+ channels, and Ca2+ entry and secretion.

Feto-placentary pathology in human parvovirus B19 infection

In view of the scarce references concerning the histological data in congenital parvovirus human B19 infection, we intend to provide a description of the pathological features observed in six autopsies. The virus was detected by DNA hybridization (ISH-DBH), PCR and electronmicroscopy (EM) in paraffin-embedded feto-placentary tissues. These cases constitute a subset from 86 Non Immunologic Hydrops Fetalis (NIHF) cases, in which a systemic complex of inflammatory/degenerative lesions of unknown etiology was visualized by optical microscopy. In one case a syphilitic process was detected, typefying a double infection. All fetuses showed a similar pathology--hydrops, hepato-splenomegaly, lung hypoplasia and erythroblastemia, the specific histological feature being the presence of intranuclear inclusions in the erythroid progenitors, in the erythropoietic visceral tissue and in blood marrow. Complex cardiopathy allied to abnormal lung lobulation and polisplenia were observed once; in 2 cases endocardial fibroelastosis was diagnosed. The pulmonary lesions were represented by dysmaturity allied to interstitial mononuclear infiltration. The hepatic consisted of cholestasis, portal fibrosis, canalicular proliferation, hemossiderosis, focal necroses and giant cell transformation. The central nervous system lesions were predominantly anoxic although the autolysis impaired a correct diagnosis.

Endoscopy of mandibular cysts after cystostomy: a preliminary report

PURPOSE

This study evaluated the use of endoscopy to explore mandibular cysts after cystostomy.

MATERIALS AND METHODS

Six mandibular cysts were explored with a fiber endoscope immediately after cystostomy, allowing evaluation of the appearance of the cyst lining and biopsies to be performed.

RESULTS

The lining of the cyst wall had a pearly appearance. It was easy to visualize the interior of large cysts extending from the body into the ramus, as well as to explore lobes and recesses. In no case did biopsies of the cyst lining indicate a neoplasm.

CONCLUSIONS

Fiber endoscopy is a useful technique for the exploration and monitoring of mandibular cysts after cystostomy, particularly in cases in which the cyst extends from the body into the ramus.

Human parvovirus B19 infection and hydrops fetalis in Rio de Janeiro, Brazil

Formalin-fixed paraffin embedded lung and liver tissue from 23 cases of non immune hydrops fetalis and five control cases, in which hydrops were due to syphilis (3) and genetic causes (2), were examined for the presence of human parvovirus B19 by DNA hybridisation. Using in situ hybridisation with a biotynilated probe one positive case was detected. Using 32P-labelled probes in a dot blot assay format, five further positives were obtained. These were all confirmed as positive by a nested polymerase chain reaction assay. Electron microscopy revealed virus in all these five positive cases. The six B19 DNA positive cases of hydrops fetalis were from 1974, 1980, 1982, 1987 and 1988, four of which occurred during the second half of the year, confirming the seasonality of the disease.

Synthesis and structural, conformational, biochemical, and pharmacological study of new compounds derived from tropane-3-spiro-4'(5')-imidazoline as potential 5-HT3 receptor antagonists

A series of tropane-3-spiro-4'(5')-imidazolines was synthesized and studied by 1H and 13C NMR spectroscopy, and the crystal structure of 2'-(1H-indol-3-yl)tropane-3-spiro-4'(5')-imidazoline hydrochloride 5(6)f was determined by X-ray diffraction. In CD3OD solution, compounds 5(6)a-f display the same preferred conformation. The pyrrolidine and piperidine rings adopt an envelope conformation flattened at N8 and a distorted chair conformation puckered at N8 and flattened at C3, respectively, with the N-substituent in the equatorial position with respect to the piperidine ring. This conformation is similar to that observed for compound 5(6)f in the solid state. From binding studies on the compounds synthesized, compound 5(6)d demonstrated the ability to efficiently displace the binding of [3H]GR65630 to bovine brain area postrema membranes to an extent comparable to MDL 72222. In the von Bezold-Jarisch reflex, compound 5(6)d was equipotent with metoclopramide. It is, therefore, likely that the imidazoline ring may provide a useful bioisosteric replacement for the carbonyl group in 5-HT3 antagonists.

Morphology of pulmonary extralobar sequestration in neonatal death by hyaline membrane disease

We present an unusual case of extralobar pulmonary sequestration associated with hyaline membrane disease (HMD) that caused the death of a premature baby in the first day of life. The sequestered parenchyma was nourished by an aberrant aortic vessel. Notable was the presence of typical HMD in all the lung parenchyma perfused by the pulmonary artery; the sequestered lung tissue presented a dysplastic structure compatible with CCAM. A few similar cases have been found in the literature. In all of the reported cases there are morphologic aspects characteristic of HMD in the portions normally receiving blood from the pulmonary artery. These findings suggest the importance of the blood pulmonary circulation in the pathogenesis of HMD, whose exact causes are not fully known.

Morphological and virological studies in six autopsies of children with adenovirus pneumonia

Pulmonary lesions compatible with adenovirus infection were detected by gross and microscopic examination of autopsy tissues from children aged from 5 to 34 months. Hepatic lesions indicative of systemic infection were also found in four of the children. The viral etiology was confirmed in three cases by in-situ hybridization, electron-microscopy and immunofluorescence performed in paraffin-embedded tissues, and in one case by cell culture isolation of adenovirus type 2 from nasopharyngeal exudate. Routine testing by methods additional to conventional light microscopy would probably have revealed a larger number of adenovirus infections among the 1,103 autopsy records analyzed in this study.

Mechanism of blockade by flunarizine of bovine adrenal catecholamine release

How flunarizine, a class IV Ca2+ antagonist, affects the secretion of catecholamines in response to nicotinic receptor activation (10-s pulses with 100 microM dimethylphenylpiperazinium, DMPP) or direct depolarization of chromaffin cells (10-s pulses with 100 mM K+ and 2.5 mM Ca2+, 100 K+/2.5 Ca2+) was studied in bovine adrenal glands perfused with an oxygenated Krebs-Tris solution at 37 degrees C at a rate of 20 ml/min. Experimental protocols aimed to test voltage and time dependence of the flunarizine blocking effects on secretion are described. The DMPP pulses released an average of 217 micrograms catecholamines and the K+ pulses, an average of 117 micrograms. These responses were blocked by flunarizine concentration dependently; IC50s were 3.7 microM for DMPP and 1.1 microM for K+. Under polarizing conditions (60-s perfusion with a solution containing 5.9 mM K+ and nominally zero Ca2+), a 10-s pulse with 100 K+/2.5 Ca2+ released 117 +/- 26 micrograms of catecholamines (n = 12). Under depolarizing conditions (60-s perfusion with 118 K+/0 Ca2+ prior to the Ca2+ pulse), the pulse with 118 K+/2.5 Ca2+ released 307 +/- 36 micrograms of catecholamines (n = 14). Flunarizine blocked these secretory responses equally and concentration dependently with an IC50 of 3.4 microM under polarizing conditions and of 3.8 microM under depolarizing conditions. Thus, blockade by flunarizine of secretion was apparently not voltage-dependent. The blockade was, however, clearly dependent on the time of exposure of the adrenal medullary tissue to flunarizine.(ABSTRACT TRUNCATED AT 250 WORDS)

Permeation and inactivation by calcium and manganese of bovine adrenal chromaffin cell calcium channels

Stimulation of fura-2-loaded bovine chromaffin cells with the nicotinic agonist 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP; 10 microM) or depolarization with high [K+] (50 mM) accelerated the entry of both Ca2+ and Mn2+, used here as a Ca2+ surrogate for Ca2+ channels. Removal of extracellular Na+ prevented the effects of DMPP but did not modify the effects of K+, indicating that Na+ is necessary for coupling of Ca2+ entry to the nicotinic receptor activation and that the ionophore associated with it is functionally impermeable to divalent cations. DMPP- as well as K(+)-evoked Ca2+ and Mn2+ influx were blocked completely by Ni2+ but only partially by dihydropyridines, suggesting that, in addition to L-type Ca2+ channels, other Ca2+ entry pathways may be present. Inactivation of Ca2+ channels, followed by comparing the rates of Mn2+ uptake at different time periods after the addition of DMPP or high K+, did not happen in the absence of extracellular Ca2+. When 1 mM Ca2+ was present, a delayed inhibition (half time, 10-20 s) was observed, suggesting that it is not due to the entry of Ca2+ itself but to the increase of the cytoplasmic Ca2+ concentration ([Ca2+]i) that takes a few seconds to develop. The influx of Ca2+, estimated from the increase of [Ca2+]i, was also impaired in a time-dependent fashion by previous entry of Mn2+. Inactivation of Ca2+ entry was achieved at estimated mean intracellular Mn2+ concentrations as low as 10(-9) M.

In vitro denervation of the rat vas deferens through hypothermic storage

1. The rat vas deferens was excised, stored at 4-6 degrees C and tested after 24, 48, 72 or 96 h for its contractile activity and for the presence of innervation. 2. The maximal contractile capacity of the vas, tested through cumulative concentrations of barium chloride (3 x 10(-2) M) was progressively reduced from about 110 mm to about 63 mm after 72 h, without further decay after 96 h. Spontaneous rhythmic contractions were practically absent. 3. A loss of endogenous pools of catecholamines was indicated by four parameters: (a) a decline of about 80% after 24 h and of more than 95% after 48 h of the contractile effect of the indirect sympathomimetic agonist tyramine; (b) a fall of about 20%, 50% and 85% on the concentration of noradrenaline, respectively after 24, 48 and 72 h; (c) a fall of about 25% and 90% after respectively 24 and 48 h, of the activity of dopamine-beta-hydroxylase (DBH); (d) a decline of noradrenaline-induced histofluorescence on cross sections of the vas. 4. A loss of neuronal uptake capacity was indicated by: (a) a progressive variation of the apparent affinity for adrenaline, expressed as pD2 values, that increased by about 1.5 log units (corresponding to a 30 fold potentiation) after 72 h, and (b) a reduction of the ability of cocaine to potentiate the contractile effects of adrenaline. 5. The pD2 values for barium chloride, 5-hydroxytryptamine (5-HT) and histamine were not significantly changed, while the corresponding value for acetylcholine was slightly but significantly reduced by about 0.8 log units. 6. The maximal heights of concentration-response curves for noradrenaline, acetylcholine, histamine and 5-HT were reduced by 42-66% in relation to controls. However, when this reduction was measured in relation to the corresponding barium effect, by means of the relative responsiveness ratio (p), a small though significant increase was observed for noradrenaline, and a fall for the other drugs.7. It is concluded that: (1) the values for the various biochemical and pharmacological parameters decline at different rates, though revealing altogether that denervation is completed by at least 85% after 72 h of hypothermic storage; (2) two of the results, i.e., the lack of spontaneous rhythmic contractions and the lack of increased contractile effects for acetylcholine, 5-HT and histamine, indicate that in these conditions the vas is devoid of the so-called nonspecific signs of denervation.

Membrane-mediated effects of the steroid 17-alpha-estradiol on adrenal catecholamine release

The effects of 17-alpha-estradiol on the secretion of catecholamines from the perfused bovine and cat adrenal gland and bovine chromaffin cells in culture elicited by dimethylphenylpiperazinium (DMPP), methacholine and high potassium were studied. In perfused cat adrenal glands, secretion of catecholamines evoked by pulses of DMPP (1 microM for 30 sec) was decreased by 17-alpha-estradiol at concentrations of 1 and 10 microM by 50 and 80%, respectively. However, secretion evoked by pulses of methacholine (3 microM for 30 sec) was not affected by 1 microM of 17-alpha-estradiol and was affected to a variable extent by 10 microM 17-alpha-estradiol. Catecholamine secretion evoked by higher concentrations of methacholine (100 microM for 60 sec) was reduced by 50% by 10 microM 17-alpha-estradiol. 17-alpha-Estradiol decreased secretion evoked by pulses of 120 mM K+ for 10 sec to a similar extent in the perfused bovine and cat adrenal gland. The 45Ca++ uptake into bovine chromaffin cells in culture stimulated by DMPP (100 microM for 10 sec) or high K+ (59 mM for 10 sec) was almost inhibited completely by 100 microM 17-alpha-estradiol. The rapid action precludes a classical genomic mechanism and suggests effects at the cell membrane.

Enterovirus associated placental morphology: a light, virological, electron microscopic and immunohistologic study

The purpose of this study was to identify the possible effect of enteroviruses on placental tissue. Seventy-eight pregnant women were studied throughout their pregnancy: enteroviral infection was detected by faecal viral isolation and seric neutralization of previously identified virus in cell culture. In 19 cases of confirmed maternal infection, placentae were examined grossly, by optical microscopy, immunohistochemical and electron microscopic methods. Ten term placentae from women included in the study, with no clinical, serological or virological evidence of enteroviral infection, were used as control, and examined by gross and optical microscopy. In 17 specimens (echovirus-coxsackievirus) an haematogenous placentitis was suspected on the basis of gross observation. Microscopic lesions were similar to those found in other viral infections, with specific features. The nature of the inflammatory reaction pointed to the presence of an acute type of haematogenous placentitis, not present in placentae of the control group. The authors (AA) comment on the results and present the hypotheses about the available data: (1) maternal enteroviremia and faecal virus shedding without placental invasion, placentary damage being an unspecific consequence of infection; (2) direct virus-induced injury is not the only possible cause for the lesions: (3) placental enteroviral infection occurred with placental pathology but the virus did not cross the organ as the newborn had no signs of infection.

Characterization of two chromaffin cell populations isolated from bovine adrenal medulla

Cultures of chromaffin cells isolated from the bovine adrenal medulla have been extremely useful for investigating secretory mechanisms, but such cultures used up to the present time represent mixed populations of adrenergic and noradrenergic cells. This report describes how, with slight modifications to standard procedures, two separate chromaffin cell populations may be separated from bovine adrenal medullae. These two cell fractions have been characterized by biochemical, immunocytochemical, and morphological techniques as enriched populations of adrenergic or noradrenergic cells, respectively. The adrenergic cell-enriched fraction consists of greater than 90% adrenergic cells, whereas the noradrenergic cell-enriched fraction contains greater than 60% noradrenergic cells. We also demonstrate that these cells may be cultured with their secretory machinery intact: analysis of secreted catecholamines from nicotine- or high K+ concentration-stimulated cells cultured from each fraction confirms that adrenaline is the major catecholamine secreted by one fraction, whereas noradrenaline is mainly secreted by the other.

Reinnervation of the transplanted vas deferens: differential recovery of various biochemical and pharmacological parameters

Biochemical and pharmacological parameters were used to follow the innervation characteristics of the rat was deferens transplanted (T) to the caecum. After about 5 months, a regeneration of autonomic nerves was clearly shown: first, by a complete recovery of neuronal uptake, indicated by: a) potentiation by cocaine of epinephrine (EPI) dose-response curves (T = 1.47 +/- 0.25, controls (C) = 1.50 +/- 0.14 log units); b) reversion to normal levels of pD2 values for norepinephrine (NE) and EPI (T = 6.6 +/- 0.1; 7.0 +/- 0.1, and C = 6.4 +/- 0.1; 6.9 +/- 0.1, respectively); second, a partial restoration of nerve terminals, and corresponding pools of NE, which was seen through histofluorescence and was indicated by a percent increase of: a) NE content, 47% (T = 3.8 +/- 0.8, C = 8.5 +/- 0.7 micrograms/g); b) dopamine-beta-hydroxylase (DBH) activity, 37% (T = 136 +/- 80, C = 364 +/- 15 nmol(hr.g); c) release of NE by 57 mM-potassium, 23% (T = 33.0 +/- 12.0, C = 147 +/- 14 ng/g. 5 min). Yet, two peculiarities of denervated organs remained practically unchanged even after 5-month transplantation: NE supersensitivity, measured by the relative responsiveness (rho) ratio (T = 0.96 +/- 0.02, C = 0.69 +/- 0.03), and tyramine-induced contraction, that was recovered by only 14% (T = 10.0 +/- 2.4, C = 72.0 +/- 3.5 mm). This differential recovery of the aforementioned parameters is discussed in the light of receptor mechanisms and functional changes following reinnervation.

Separate [3H]-nitrendipine binding sites in mitochondria and plasma membranes of bovine adrenal medulla

1. Two binding sites for the 1,4-dihydropyridine (DHP) derivative [3H]-nitrendipine have been found in the bovine adrenal medulla. The high-affinity site (Kd = 0.48 nM and Bmax = 128 fmol mg-1 protein) was specifically located in purified plasma membranes. The low-affinity site (Kd = 252 nM and Bmax = 169 pmol mg-1 protein) was located only in mitochondria. Chromaffin granule membranes lacked specific binding sites for [3H]-nitrendipine. 2. Kinetic analysis of the rates of association and dissociation of [3H]-nitrendipine, saturation isotherms and displacement experiments with unlabelled nitrendipine and PN200-110 revealed single, homogeneous populations of high- and low-affinity sites in plasma and mitochondrial membranes, respectively. 3. The high affinity site was sensitive to Ca2+ deprivation and heating; it was practically unaffected by changes in ionic strength of the medium and its optimal pH was slightly alkaline. This site exhibited a strong DHP stereoselectivity; diltiazem increased and verapamil decreased the affinity of [3H]-nitrendipine. 4. In contrast, binding of [3H]-nitrendipine to the low affinity site was more heat resistant and less affected by Ca2+ removal. Its optimal pH was slightly acid and the increase in ionic strength enhanced the number of available sites. The site had no DHP stereoselectivity. Verapamil decreased the dissociation constant of [3H]-nitrendipine acting in a non-competitive manner; diltiazem did not affect equilibrium binding parameters of [3H]-nitrendipine. 5. These results suggest that both biding sites reflect different receptor entities. The high-affinity binding site corresponds to the dihydropyridine receptor associated with the L-type calcium channel. The function of the mitochondrial, low-affinity binding site is, at present, unknown.

Congenital echo virus infection--morphological and virological study of fetal and placental tissue

A prospective study of 78 pregnant women was undertaken to detect maternal enterovirus infection. Maternal faecal specimens and blood samples, placental and fetal tissue were taken for viral study, electron microscopy, histochemistry, and morphological examination. We present the post-mortem findings in three fetuses whose maternal infection was detected before delivery by isolation of ECHO virus type 33 and type 27 from faecal specimens and/or placental and fetal tissues. The morphological aspects were similar in all cases and included an acute infection of the placenta and hypoxic/hypotensive injury to fetal organs. In one case, viral particles were detected by electron microscopy of the fetal liver. This series of cases of intrauterine ECHO virus infection confirms the potential gravity of such infection during pregnancy and the need to prevent enteroviral disease.

Enterovirus isolation from foetal and placental tissues

Four spontaneous abortions and two stillbirth occurred during a prospective survey following the teratogenicity of echoviruses in 80 pregnant women selected at random from the Antenatal Care Service. Echovirus types 19, 27, and 33. Coxsackie B2 and B6 were isolated from placental and foetal tissues (brain, liver, kidney, heart, and spleen). The mothers also excreted the virus by faeces at least twenty days before abortion and responded serologically, indicating active virus infection. Almost all aborted children were anomalous with signs of viral infection.

Phosphorylation of myosin light chain from adrenomedullary chromaffin cells in culture

The myosin-light-chain (MLC) phosphorylation accompanying catecholamine release in chromaffin cells was investigated with the objective of assessing the possible role of this contractile protein in catecholamine secretion. The electrophoretic characteristics of adrenomedullary MLC were determined by immunochemical techniques using two different specific antibodies. The identified 22 kDa phosphoprotein was mainly present in the cytosol, as demonstrated by ultracentrifugation and immunocytochemical analysis. A part of this protein was located on, or close to, the plasma membrane. Cell stimulation by secretagogues resulted in a Ca2(+)-dependent 32P incorporation into MLC, the time course of this process being related to catecholamine release. These findings were supported by a two-dimensional gel-electrophoretic analysis by which means this protein was resolved into two acidic forms. A role for Ca2(+)-calmodulin and Ca2(+)-phospholipid kinases in adrenomedullary MLC phosphorylation is reported. The results obtained suggest a regulatory role for such a protein in the underlying exocytotic event.

Separate binding and functional sites for omega-conotoxin and nitrendipine suggest two types of calcium channels in bovine chromaffin cells

Purified adrenomedullary plasma membranes contain two high-affinity binding sites for 125I-omega-conotoxin, with KD values of 7.4 and 364 pM and Bmax values of 237 and 1,222 fmol/mg of protein, respectively. Dissociation kinetics showed a biphasic component and a high stability of the toxin-receptor complex, with a t1/2 of 81.6 h for the slow dissociation component. Unlabeled omega-conotoxin inhibited the binding of the radioiodinated toxin, adjusting to a two-site model with Ki1 of 6.8 and Ki2 of 653 pM. Specific binding was not affected by Ca2+ channel blockers or activators, cholinoceptor antagonists, adrenoceptor blockers, Na+ channel activators, dopaminoceptor blockers, or Na+/H+ antiport blockers, but divalent cations (Ca2+, Sr2+, and Ba2+) inhibited the toxin binding in a concentration-dependent manner. The binding of the dihydropyridine [3H]nitrendipine defined a single specific binding site with a KD of 490 pM and a Bmax of 129 fmol/mg of protein. At 0.25 microM, omega-conotoxin was not able to block depolarization-evoked Ca2+ uptake into cultured bovine adrenal chromaffin cells depolarized with 59 mM K+ for 30 s, whereas under the same conditions, 1 microM nitrendipine inhibited uptake by approximately 60%. When cells were hyperpolarized with 1.2 mM K+ for 5 min and then Ca2+ uptake was subsequently measured during additions of 59 mM K+. Omega-conotoxin partially inhibited Ca2+ uptake in a concentration-dependent manner. These results suggest that two different types of Ca2+ channels might be present in chromaffin cells. However, the molecular identity of omega-conotoxin binding sites remains to be determined.

Sodium-dependent and sodium-independent nicotine-evoked catecholamine release from cat adrenals

Cat adrenal glands were stimulated with nicotine under Na-free conditions; subsequently, Na was gradually introduced as a continuously increasing gradient from 0 to 134 mM. With this experimental approach two catecholamine secretory peak responses were obtained: one was Na-independent and the second was dependent of this cation. This second response was greater in magnitude than the first and selectively blocked by (+)PN200-110, a potent dihydropiridine Ca channel blocker. The results suggest that Na, although not essential to evoke some degree of secretion, plays, however, a prominent role in amplifying the nicotine-secretory response by causing cell depolarization and opening of voltage-dependent Ca channels.

Placental morphology in cytomegalovirus infection

Three groups of placentae from 27 cases of cytomegalovirus infection were examined morphologically and by specific immunofluorescence. Placentae in Group 1 (four cases) had a mean gestational age of 24.5 +/- 2.5 weeks; those in Group 2 (11 cases) had a mean gestational age of 36.4 +/- 2.7 weeks; those in Group 3 (12 cases) had a mean gestational age of 40 +/- 1.8 weeks. A tendency towards increased placental weight was observed. In 23 cases, a haematogenous placentitis was suspected on gross examination. Some specific features were detected on light microscopy. In Group 1 the lesions were represented by pronounced dysmaturity of villous structures, diffuse reparative villitis and intervillitis allied to an abundance of cytomegalic cells and areas of necrosis and calcification. In Group 2 a chronic active process was indicated by the presence of vascular involvement, proliferative-necrotic and reparative villitis and fresh villous necrosis; cytomegalic cells were scarce. In Group 3 placentae there was a predominance of villous plate lesions similar to those found in the septicaemic phase of maternal infections; necrotizing, proliferative and, rarely, reparative villitis was present; cytomegalic cells were rare. We may conclude that placental morphology needs to be substantiated by special laboratory techniques for the detection of cytomegalovirus infection.

Contractile responses of the guinea-pig vas deferens to the combination of vanadium ions with ouabain

1. Vanadate and vanadyl ions (10(-5)-10(-2) M) induced dose-dependent rhythmic contractions of the vas deferens of reserpine-treated guinea-pigs. The Na, K-ATPase blocker ouabain (10(-5)-10(-3) M) induced similar, though smaller, effects. Experiments were performed to verify if these effects are due to an interaction with the same receptor population. 2. Ouabain caused a striking potentiation of vanadium effects, which was also observed in denervated organs, indicating that a release of neuronal substances is not involved in potentiation. Similar potentiations were observed by combining vanadium with K-free solutions instead of ouabain, corroborating the involvement of the latter drug with Na, K, ATPase. 3. From the analysis of time-response and concentration-response curves, there are at least three indications that vanadium and ouabain interact with different sites: (a) the combined effect of both agonists was several times higher than the corresponding isolated effects; (b) the combined effect, expected to be independent of the order of addition of the agonist, was higher if vanadium was added before, than after ouabain; (c) the combined effect on the time elapsed between the addition of the two agonists, being higher if an interval of at least 10 min was allowed between vanadium and ouabain additions. 4. In conclusion, our results do not support the hypothesis that vanadium compounds and ouabain have a similar mechanism of action for the contraction induced in guinea-pig vas deferens.

Effects of Bay K 8644 on cat adrenal catecholamine secretory responses to A23187 or ouabain

Calcium ionophore A23187 increases the rate of spontaneous catecholamine release from cat adrenal glands perfused at 37 degrees C with oxygenated Krebs bicarbonate solution, in a time- and Ca-concentration-dependent manner. The secretory profile obtained with the ionophore was not modified in the presence of the Ca channel activator Bay K 8644. Ouabain also enhanced the rate of spontaneous catecholamine outputs in a time- and concentration-dependent manner. The threshold ouabain concentration capable of producing a clear, yet delayed secretory response was 10(-6) M. Increasing ouabain concentrations up to 10(-4) M enhanced catecholamine release and shortened the time to peak release. The dihydropyridine Ca channel activator Bay K 8644 (10(-6) M) markedly potentiated the secretory effects of all ouabain concentrations used (10(-7)-10(-4) M). However, the most impressive potentiations were seen at 10(-5)M ouabain; while at this concentration ouabain alone released 2.6 +/- 0.07 micrograms catecholamines per 30 min, in the presence of Bay K 8644 the release was 73.4 +/- 5.7 micrograms per 30 min. Conversely, at a fixed ouabain concentration (10(-5) M), the potentiation was also dependent on the Bay K 8644 concentration (10(-8)-10(-5) M). Although K deprivation inhibits Na pumping as does ouabain, Bay K 8644 did not modify the rate of catecholamine release evoked by K removal from the perfusion medium. Potassium deletion, nimodipine or high Mg all reversed the fully developed secretory response evoked by ouabain plus Bay K 8644. In glands depolarized by continuous perfusion with high K solutions, once the secretory response was inactivated, the introduction of ouabain caused an enhancement of the catecholamine secretory rate. This increase was dependent on the extracellular Na concentration and was not affected by Bay K 8644. In the presence of 6 mm Na the secretory effects of Bay K 8644 plus ouabain were abolished. 7 These results are compatible with the following conclusions: (i) Bay K 8644 potentiates only those catecholamine secretory responses that are known to be mediated through the activation of voltagesensitive Ca channels; the drug does not seem to affect secretory responses by acting on the membrane Na/Ca exchange system or at some intracellular Ca-dependent component of the secretory machinery of Ca buffering systems. (ii) It is likely that ouabain enhances the rates of adrenal catecholamine release by a dual mechanism: chromaffin cell depolarization and activation of a membrane Na/Ca exchange system.

Congenital toxoplasmic myocarditis: case report of an unusual presentation

Extensive calcification of the heart, involving predominantly the right ventricle and interventricular septum, was observed in a 3-h-old baby. The aetiology of the condition was attributed to infection by Toxoplasma gondii, based on the presence of several visceral lesions allied to the identification of the microorganism. The case is reported in view of the rarity of the type of the heart lesion. It is considered that calcification of the myocardium is secondary to vascular, inflammatory or toxic condition. The factors implicated in the pathogenesis of this unusual myocardial lesion are discussed.

Placental pathology in congenital rubella

Two groups of placentae from 18 cases of maternal rubella were examined morphologically and virologically. Placentae in Group I (four cases) had a mean gestational age of 21 +/- 1.9 weeks, whilst those in Group 2 (14 cases) had a mean gestational age of 38 +/- 2.8 weeks. A tendency to hypoplasia was observed. The microscopic lesions were similar to those found in other viral infections but in each group some specific features were noted. Only placentae of Group I showed nodules of villi agglutinated by fibrin. This lesion suggested recent maternal infection. Attention is drawn to the presence of abnormal areas of lobular rarefaction due to dysmaturity of villous stem and terminal villi. This aspect was more diffuse and accentuated in Group 2 placentae. Villitis of reactive, necrotic, proliferative and reparative types was seen only in placentae of Group 2. Devastating villitis was not observed. Inclusions in placental cells suggested rubella infection. The lesions were non-specific and hence stress the need for virological examination of the placenta, immunofluorescence studies and electron microscopy to confirm the diagnosis.

Hospital costs of surgical complications

Fifteen patients who had a general or gynecologic abdominal operation were operated on a second time for a complication of the first operation. There were three deaths. Extra costs attributable to the complications amounted to +211,503, of which one third was uncollectible. One half of the extra hospital days for surviving patients were spent in the intensive care unit.

Orthograde and retrograde axonal transport of calmodulin in a cat noradrenergic neurone

Subcellular distribution studies of calmodulin in cat sympathetic ganglia demonstrated that about 90% of the protein remained in the 27,000 g supernatant, suggesting that it is a cytosolic protein. Only 4.5% was recovered in the microsomal fraction pellet. The inferior mesenteric ganglia contained 93.3 +/- 3 ng calmodulin per ganglion, and segments of unligated cat hypogastric nerves had 6.53 +/- 0.32 ng per 5 mm segment. When the nerve was ligated in the middle and left in the cat for 1-6 days, substantial amounts of calmodulin accumulated in segments of nerve immediately proximal (P1) and distal (D1) to the ligature. The amounts found in P1 amounted to 15.3, 20, 30.4 and 39.4 ng calmodulin per 5 mm segment 1, 2, 3 and 6 days after ligation, respectively. The average rate of transport was 5.5 mm per day, which corresponds to a slow component b of axonal transport (SCb). The accumulation of calmodulin in D1 was also increased with the time of ligation. After 1, 2, 3 and 6 days, the amounts of the protein found in D1 were 14.4, 17.7, 19 and 21 ng per 5 mm segment, respectively. The calculated mean rate for the retrograde transport was 3.9 mm per day. Decentralization of the inferior mesenteric ganglia did not affect the rate of accumulation of calmodulin or the basal amounts found in ganglia and nerves. Local injection inhibited the orthograde, but not the retrograde axonal transport of the protein. It is concluded that calmodulin undergoes a process of slow orthograde axonal transport probably incorporated into the axoplasmic matrix of a network of actin microfilaments. The protein is also transported in a retrograde manner.

Pharmacological dissection of receptor-associated and voltage-sensitive ionic channels involved in catecholamine release

The experiments were designed to quantify pharmacologically the degree of participation of channels associated with the nicotinic cholinoceptor compared with voltage-sensitive channels during the evoked release of [3H]noradrenaline from prelabelled 3-7-day old cultured bovine adrenal chromaffin cells. To achieve this purpose we studied (a) the release of [3H]noradrenaline evoked by secretagogues known to trigger the secretory response through activation of receptor-associated channels (acetylcholine, nicotine), voltage-sensitive Na+ (veratridine) and Ca2+ (high [K+] ) channels or direct, channel-independent promotion of Ca2+ entry (ionomycin); and (b) the selective blockade of some of those responses using ionic manipulations (Na+ deprivation, high Mg2+) or drugs known to block the activity of receptor-operated channels (imipramine, cocaine), voltage-dependent Na+ (tetrodotoxin) or Ca2+ (nitrendipine) channels. Inhibition by nitrendipine, a potent Ca2+ antagonist, of the secretory responses to both nicotine and high [K+] indicates a preferential Ca2+ entry through voltage-sensitive channels during the secretory process. Blockade by cocaine and imipramine of the release of [3H]noradrenaline evoked by acetylcholine and nicotine, without alteration of the responses to high [K+], veratridine or ionomycin, speaks in favor of a selective inactivation of the nicotinic receptor-associated channel. Since Na+ deprivation abolished [3H]noradrenaline release produced by nicotine, it seems that Na+ entry through the receptor-linked ionophore might be a primary event in the initiation of the secretory process; the fact that tetrodotoxin did not affect the release favors this view. However, veratridine induced a tetrodotoxin-sensitive secretory response, suggesting the presence of voltage-sensitive Na+ channels which might physiologically be used to propagate action potentials through gap junctions between adjacent chromaffin cells, only in the intact gland.(ABSTRACT TRUNCATED AT 250 WORDS)