Corbicula fluminea rapidly accumulate pharmaceuticals from an effluent dependent urban stream.

Freshwater bivalve populations are stressed by watershed development at the global scale. Though pharmaceuticals released from wastewater treatment plant effluent discharges are increasingly reported to bioaccumulate in fish, an understanding of bioaccumulation in bivalves is less defined. In the present study, we examined accumulation of 12 target pharmaceuticals in C. fluminea during a 42 day in situ study in Pecan Creek, an effluent dependent wadeable stream in north central Texas, USA. Caged clams were placed at increasing distances (5 m, 643 m, 1762 m) downstream from a municipal effluent discharge and then subsampled on study days 7, 14, 28 and 42. Acetaminophen, caffeine, carbamazepine, diltiazem, diphenhydramine, fluoxetine, norfluoxetine, sertraline, desmethylsertraline, and methylphenidate were identified in C. fluminea whole body tissue homogenates via isotope dilution liquid chromatography-tandem mass spectrometry. Tissue concentrations ranged from low µg/kg (methylphenidate) to 341 µg/kg (sertraline). By study day 7, rapid and apparent pseudo-steady state accumulation of study compounds was observed in clams; this observation continued throughout the 42 d study. Notably, elevated bioaccumulation factors (L/kg) for sertraline were observed between 3361 and 6845, which highlights the importance of developing predictive bioaccumulation models for ionizable contaminants with bivalves. Future research is also necessary to understand different routes of exposure and elimination kinetics for pharmaceutical accumulation in bivalves.

Peritoneal mucinous cystadenocarcinoma of probable urachal origin: a challenging diagnosis.

This report describes the case of a mucinous cystadenocarcinoma of probable urachal origin that presented with mass effect, precipitating deep venous thrombosis and pulmonary embolism. The patient presented with acute symptoms of leg swelling, pain and dyspnoea, and a vague awareness of lower abdominal distension. Computer tomography showed a cystic mass closely related to the anterior abdominal wall and the superior aspect of the bladder. A 1500 cm(3) cyst adherent to the dome of the urinary bladder was resected on laparotomy. Partial cystectomy was not carried out in the belief that the cyst represented a benign lesion. Subsequent imaging has shown cystic changes in the anterior bladder wall, and the patient has been referred for partial cystectomy.

Decision-case mix model for analyzing variation in cesarean rates.

This article contributes a decision-case mix model for analyzing variation in c-section rates. Like recent contributions to the literature, the model systematically takes into account the effect of case mix. Going beyond past research, the model highlights differences in physician decision making in response to obstetric factors. Distinguishing the effects of physician decision making and case mix is important in understanding why c-section rates vary and in developing programs to effect change in physician behavior. The model was applied to a sample of deliveries at a hospital where physicians exhibited considerable variation in their c-section rates. Comparing groups with a low versus high rate, the authors' general conclusion is that the difference in physician decision tendencies (to perform a c-section), in response to specific obstetric factors, is at least as important as case mix in explaining variation in c-section rates. The exact effects of decision making versus case mix depend on how the model application defines the obstetric condition of interest and on the weighting of deliveries by their estimated "risk of Cesarean." The general conclusion is supported by an additional analysis that uses the model's elements to predict individual physicians' annual c-section rates.

Assessment of the estrogenicity and toxicity of a domestic wastewater effluent flowing through a constructed wetland system using biomarkers in male fathead minnows (Pimephales promelas rafinesque, 1820).

The toxicity and estrogenicity of a final treated municipal effluent was examined while flowing through a constructed wetland in north-central Texas, USA. Fish data were collected, and a baseline wetland characterization was performed to assess wetland treatment potential for these effluent properties. Vitellogenin (VTG), gonadosomatic index (GSI), hepatosomatic index (HSI), and secondary sexual characteristics were biomarkers used in fish models to assess aqueous estrogenicity. Biological indicators used to assess overall fish health included hematocrit and condition factor. Estrogenic nature of final sewage treatment works effluent was screened, concurrent with a three-week fish exposure, via gas chromatography/mass spectrometry for target estrogenic compounds, including 17beta-estradiol, ethynylestradiol, bisphenol A, nonylphenolic compounds, phthalates, and DDT. The VTG in Pimephales promelas was measured after exposure at four sites in a treatment wetland and was significantly elevated (p < 0.0001) in fish exposed at the inflow site. The GSIs were significantly less (alpha = 0.001) at the inflow site. At wetland sites closest to the inflow, secondary sexual characteristics, tubercle numbers, and fatpad thickness were less (alpha = 0.0001) than in laboratory controls. The HSIs and density of male breeding stripes were not significantly different from those of laboratory controls. However, elevated HSIs were found at the inflow site. Hematocrit and condition factors were both less (alpha = 0.001) in effluent-exposed fish at wetland sites closer to the inflow than in control fish or fish further downstream.

[Intraepithelial phototherapeutic keratectomy and alcohol delamination for recurrent corneal erosions--two minimally invasive surgical alternatives]. / Intraepitheliale Phototherapeutische Keratektomie und Alkohol-Abrasio zur Therapie der rezidivierenden Erosio corneae - zwei minimalinvasive chirurgische Alternativen.

BACKGROUND: Phototherapeutic keratectomy (PTK) has become established as a successful therapy for recurrent corneal erosions. After epithelial debridement, Bowman's lamella and anterior stroma are ablated by the Excimer laser. We have evaluated two alternative stroma-sparing treatment options, intraepithelial PTK, and alcohol delamination. PATIENTS AND METHODS: All treatments were performed in the relapse-free period. 17 eyes with recurrent corneal erosions were treated with intraepithelial PTK: from the intact epithelium, 12 - 25 microm of tissue were ablated by the Excimer laser (group I). Alcohol delamination was performed in 13 eyes (group II). Follow-up time was between 6 months and 7 years (mean 4.2 years). RESULTS: Both methods turned out to be safe, no refractive changes were detectable. After intraepithelial PTK, we saw a cumulative recurrence rate of 12 % after 1 year, 18 % after 2 years, and 24 % after 3 years, and a temporary subepithelial scaring was seen. Alcohol delamination resulted in a recurrence rate of 15 % during the whole follow-up time (no statistically significant difference compared to intraepithelial PTK), showing no haze or scarring. CONCLUSION: Both minimally invasive, stroma-sparing methods were effective for the treatment of trauma-associated recurrent erosion. The ablation of Bowman's lamella or anterior stroma does not seem to be necessary. However, for basal membrane dystrophy, we recommend PTK after epithelial debridement for the partial ablation of Bowman's lamella.

[The influence of cryoprotective solutions on the ultrastructure of rabbit corneal endothelium (author's transl)]. / Elektronenmikroskopische Untersuchungen über den Einfluss verschiedener Gefrierschutzlösungen auf die Ultrastruktur des Endothels konservierter Hornhäute.

A series of rabbit corneae was preserved at -196 degrees C in liquid nitrogen using five different cryoprotective solutions: (1) 5% dextran T 40, (2) 10% polyvinylpyrrolidone, (3) 5% dextran T 40 + 10% polyvinylpyrrolidone + dimethyl sulfoxide, (4) 25% rabbit albumin + 10% polyvinylpyrrolidone, (5) 25% rabbit albumin + dimethyl sulfoxide. After thawing the corneae, the influence of the different cryoprotective solutions on the ultrastructure of corneal endothelium was evaluated and compared with fresh corneae. The results were as follows: (1) Using 5% dextran T 40 or 10% polyvinylpyrrolidone or 25% rabbit albumin as cryoprotective solutions marked intracellular damage. (2) Adding dimethyl sulfoxide to the solutions cryopreservation appeared to be more successful at the cellular basis, despite the freezing and thawing procedure mediated moderate intracellular changes. Cryopreservation including dimethyl sulfoxide renders better conditions for successful corneal grafting in the light of ultrastructural aspects.

[Tonography of the eye in the diagnosis of myasthenia gravis (author's transl)]. / Die Augen-Tonographie in der Diagnostik der Myasthenia gravis.

Tonography of the eye was performed in 15 patients with proven myasthenia gravis and ten control subjects, before and after administration of edrophonium (Tensilon). In nine myasthenics there was definite intra-ocular pressure rise after an average of 20 seconds. In control subjects a comparable pressure rise did not occur. Tonography was superior to results obtained with serial stimulation of the ulnar nerve. The results confirm that tonography of the eye is a valuable and reliable diagnostic test of myasthenia gravis.

[Tectonic keratoplasties using cryopreserved corneae (author's transl)]. / Tektonische Keratoplastiken mit gefrierkonservierten Hornhäuten

It is reported on the treatment of severe chronic corneal diseases using cryopreserved corneae being sutured on the diseased cornea. In the majority of the patients (total number 13) defect healing was achieved. The advantages of this surgical procedure are discussed.

Concomitant Subdural and Preretinal hemorrhage.

A case report is presented of a patient with a chronic subdural hematoma, who only once had a short episode of central nervous signs. The outstanding symptom was a seemingly spontaneous introcular hemorrhage, ipsilateral to the subdural hematoma. The mechanism of the ocular manifestation is discussed.

Goldmann applanation versus hand-applanation and .schiötz indentation tonometry.

For evaluation of hand-applanation tonometry comparative measurements of intraocular pressure have been carried out using the Goldmann applanation tonometer, the Draeger and Perkins hand-applanation tonometers and the Schiötz indentation tonometer. A series of 52 eyes has been tested. The statistical analysis was based on the Goldmann tonometry as a reference system. The hand-applanation tonometers were found to be in satisfactory agreement with the Goldmann tonometer, whereas the Schiötz tonometer gave significantly low values in the pressure range considered.

Electron microscopic localization of carbonic anhydrase (CA) activity in rabbit cornea.

The localization of CA activity in the rabbit cornea was investigated using a modified Hansson's method. The reaction products indicating CA activity was observed in the lateral membrane of endothelial cell, but not in the apical membrane. In cytoplasm, Golgi complex, and mitochondria of the endothelial cells no specific reaction product could be found. In epithelium, stroma, and Descemet's membrane, no reaction product was seen. The specific staining was inhibited in the control group which was treated with 10(-4)M sodium acetazolamide.

Cytochemical localiztion of nucleoside diphosphatase and thiamine pyrophosphatase activities in the rabbit corneal endothelium.

Localization of NDPase and TPPase activities in the rabbit corneal endothelium was investigated by cytochemical methods. After incubation at both pH 7.0 and 8.0, the NDPase activity was detected in cisternae of ER, nuclear envelope, and Golgi saccules, while the TPPase activity was demonstrated only in Golgi saccules. The reaction products of both enzymes were decreased when incubated at pH 8.0. The NDPase activity was inhibited by uranyl nitrate but not by sodium fluoride, while the TPPase was inhibited by fluoride but not by uranium.

[Vital staining of the endothelium of preserved corneae with Trypan Blue (author's transl)]. / Die Vitalfärbung des Endothels konservierter Hornhäute mit Trypanblau.

As a development of Capella's and Kaufman's procedure we examined on four series each with 20 pig corneae the four antifreezing solutions described by the authors singly with regard to their protective effect against freezing. After thawing at +60 degrees within 50 seconds and rehydration with 25% Serum albumin (in the fourth series 10 corneae were rehydrated with polyvinylpyrrolidone) the endothelium was stained with Trypan blue. Microphotographs were made of the endothelial surface, stained nuclei counted and the results were analysed statistically and compared one with other. Hence we could show that with increasing concentration of the antifreeze solution the vitality of the cornea increases.

[Light and electron microscopic studies on short-term preserved corneae (author's transl)]. / Licht- und elektronenmikroskopische Untersuchungen an kurzzeitkonservierten Hornhäuten

Rabbit corneae were stored at a temperature of +4 degrees C in the following media: 1. 5% Dextran T40, 2. McCoy's Medium 5a (modified), 3. Dextran T 40+McCoy's 5a Medium + gentamicin sulphate (250 mug/ml). The endothelia of the corneae were examined by light and electron microscopy after preservation for a varied number of days. The structure of the endothelia, stored for 1, 6, 12, 18 days, was compared to fresh corneal endothelial cells. The results indicate that corneae preserved in Dextran 5% T40 + McCoy's 5a Medium + gentamicin sulphate might be equivalent to fresh corneal tissue in keratoplasties.

Uptake of horseradish peroxidase (HRP) by the endothelium of the short-term stored rabbit cornea.

In vitro study of the uptake of horseradish peroxidase (HRP) by the corneal endothelium was carried out on rabbit corneae which were stored in a preserving medium for various periods. The stored corneae were incubated in HRP solution with or without adenosine triphosphate (ATP). The number of pinocytotic vesicles decreased as the storage time was prolonged. Addition of ATP to the HRP solution led to an increase in the pinocytotic vesicles in all storage periods. The pinocytosis in the 12-day stored corneal endothelium was only observed when the tissue was incubated in an HRP solution containing ATP. From these results, it was concluded that the viability of the stored corneae can be evaluated with uptake of HRP by the endothelial cell, and that the addition of ATP leads to an enhancement of pinocytotic activity in the endothelial cell.

Histochemical evaluation of enzymes in the rabbit corneal endothelium after short-term storage.

Isolated rabbit corneae were stored at a temperature of 4 degrees C in McCoy's 5a medium (modified) containing 5% dextran T 40 and gentamycin sulphate (250 mug/ml) for a varied number of days. The endothelium of the corneae was examined by light- and electron-microscopic histochemical methods for ATPase, TPPase, and SDH. The activity of each enzyme in the endothelia, stored for 6 days, was found to resemble the enzyme activities in the fresh corneal endothelium. By 8 days, the SDH activity was lowered and specific staining for ATPase and TPPase was decreased. In the 12 day-stored endothelium, the SDH and TPPase activities could not be detected. From these results, it was gathered that the isolated cornea stored in the medium for 6 days may be used in keratoplasty.

[Incus, controlled deepfrozen or in cialit conserved, after allogenetic implantation. An animal-experimental study with comparing histology (author's transl)]. / Der kontrolliert tiefgefrorene und der in Cialit konservierte Amboss nach allogenetischer Implantation. Eine tierexperimentelle Studie mit vergleichender Histologie.

The histological reactions to the implantation of allogenetic incus after conservation in Cialit or after controlled deepfreezing are described. After 5 months the incusses of both conservation technics show the same good tendency of revitalisation. Therefore the controlled deep-freezing technic does not offer an advantage compared to the Cialit conservation method at least for the present state of knowledge.

Pneumatonographic studies on normal and glaucomatus eyes.

A new methodological approach, embodied in the pneumatonograph, has been used to study the intraocular pressure, intraocular pulse and aqueous humor dynamics of normal and glaucomatous eyes. Comparative measurements of intraocular pressure in seated subjects by the Goldmann instrument and the pneumatonograph indicate close agreement over a wide range of pressures. On changing from the sitting to the supine position, it has been found by pneumatonometry that there is a significant increase of intraocular pressure in all eyes. In glaucomatous eyes, this postural response ranged up to as high as 12 mm Hg. Comparison of Schiotz and pneumatonometric pressure measurements on supine patients showed that the Schoitz values are significantly lower. This discrepancy of the values is in keeping with recent studies indicative that the Schiotz calibration is in error by 3-6 mm Hg. The coefficient of outflow facility was measured by a procedure of applanation tonography employing pressure-volume relations for the living human eye. The range of values found for normal eyes was significantly different from those of glaucoma eyes. It is concluded that pneumatonography is a useful method for improving the effectiveness of glaucoma diagnosis and clinical management.

The vascular basis of the positional influence of the intraocular pressure.

By measuring intraocular pressure in different body positions from 60 degrees semiupright to 30 degrees head down, a nonlinear relationship between IOP increase and body position was confirmed. IOP postural response in individual subjects was roughly correlated to ophthalmic arterial pressure and to the episcleral venous pressure postural response. In one series of subjects, the episcleral venous pressure increments due to posture wa; parallel to the applanation-indentation disparity in the same individual eyes. Differential tonometry with applanation or indentation procedures under blind conditions gave significantly low indentation readings. It is concluded that IOP postural response depends on arterial and venous vascular changes when subjects move from an erect to a horizontal body position. Blood expulsion from the choroid by indentation tonometry might be the reason that this tonometric procedure does not measure IOP changes based on vascular changes.