Bioremediation of Cephalexin with non-living Chlorella sp., biomass after lipid extraction

In this work, the removal of the Cephalexin by Chlorella sp., nonliving modified by extraction of lipids was evaluated. First, the microalga was grown to completing 20 days and later, the biomass of crop was centrifuged and the extraction of lipids was performed. Two adsorption experiments were performed: (1) with nonliving Chlorella sp. (control), and (2) the obtained biomass after lipid extraction. The high antibiotic removal, 71.19% and 82.77% (control), were obtained at the lowest initial concentration. The contact time between the biosorbent and the antibiotic was 2 h. The adsorption isotherm follows the Freundlich model and the obtained maximum absorption capacity was 63.29 mg of antibiotic/g of biosorbent for lipid-extracted biomass, while the control follows best to the Langmuir model with 129.87 mg/g in maximum absorption capacity. In summary, this biosorbent provides a potential alternative in the removal of Cephalexin.

Persistent microalbuminuria after treatment with renin-angiotensin axis blockers: causes and results of treatment intensification

AIMS

The first phase of this study aimed to determine the causes of persistent microalbuminuria after treatment with renin-angiotensin axis (RAA) blocking drugs. In a second phase we tried to determine if strict control of blood pressure and intensive RAA blockade could induce remission or reduction of microalbuminuria in clinical (primary care) practice.

PATIENTS AND METHODS

The study included both diabetic patients and non-diabetic hypertensive patients treated with RAA drugs in the presence of microalbuminuria. 211 patients were recruited (mean age 66.6±11.3 years, 111 men, 117 were diabetic). In the first phase treatment was optimized at standard doses. In the second phase treatment was increased during a three months period to reach a blood pressure (BP) < 130/80 mmHg by adding other antihypertensive treatment and to obtain maximal RAA blockade using long-acting drugs, increased dosage, or adding further medication at night.

RESULTS

Initial mean BP was 141±16/81±11 mmHg. BP control was unsatisfactory (control of systolic blood pressure [SBP] 19.3%; diastolic blood pressure [DBP] 37.6%). Dosage of RAA blocking drugs was inadequate in 21% of patients. Only 27.4% of patients were taking antihypertensive drugs at night. 30.1% of patients took once daily short acting drugs. During the studymean SBP was reduced to 137±13 mmHg (p < .001) and DBP decreased to 79±10 mmHg (p < .001). Control of SBP improved to 24.5% and DBP control went to 44.4%. Mean microalbuminuria decreased from 64.4±47.0 mg/day to 50.1±53.0 mg/day (p < .001) and the prevalence of microalbuminuria was reduced to 59.1%.

CONCLUSIONS

Persistent microalbuminuria was associated with poor blood pressure control and inadequate drug dosage. Low frequency of administration of drugs at night and inappropriate once-daily pills intake were frequent. Strict control of blood pressure and intensive RAA blockade significantly reduced the prevalence of microalbuminuria.

[Comparison and agreement of the Cockcroft-Gault and MDRD equations to estimate glomerular filtration rate in diagnosis of occult chronic kidney disease]

INTRODUCTION AND OBJECTIVES

The estimation of Glomerular Filtration Rate (GFR) by Cockroft-Gault or simplified MDRD functions is a powerful tool for the Chronic Kidney Disease (CKD) diagnosis. The aims of the present study are: 1)-To analyze the accuracy between Cockcroft-Gault and simplified MDRD equations in the Hidden Renal Failure (HRF) diagnosis; and 2)-To know the profile and coronary risk of patients diagnosed of HRF for each equation.

PATIENTS AND METHODS

Ten year follow-up of a cross sectional study. A total of 845 patients between 35 and 74 years old (average age 55 years, 56.7% female) without evidence of cardiovascular disease and taken care in a urban primary health center. HRF was defined as an estimated GFR <60 ml/min/1.73 m2 in patients with normal values of creatinine (<1.3 mg/dl in women and <1.4 mg/dl in men )

RESULTS

8.3% of studied population had HRF by Cockroft-Gault formula and 11.6% using MDRD. The HRF patients diagnosticated with Cockroft-Gault function were older (67.4 vs 64.4 years, p<0.001) and had a higher coronary risk using either the original Framingham equation and REGICOR function. Furthermore, those HRF patients diagnosticated using MDRD function had a higher body mass index (29.6 vs 26.3 kg/m2, p<0.001) and were women in a greater percentage. Kappa index of agreement of these two equations for diagnosis of HRF was 0,55. The HRF patients diagnosticated exclusively by the use of Cockroft-Gault function were mainly men (75%), older (69.1 vs 61.9 years, p<0.001) and they had a high coronary risk in the Framingham equation (32.7%) and REGICOR function (13.1%)

CONCLUSIONS

Cockroft-Gault and MDRD equations present a moderate agreement in HRF diagnosis (stage 3 of CKD) in patients between 35 and 74 years old. If we only use the MDRD function, a group of HRF patients would be excluded. This population was mainly male (75%), older (69 years old), with a high coronary risk estimated by original Framingham and REGICOR equations, and confirmed in the ten years follow-up of these patients.

Valoración clínico-radiológica de las vertebroplastias

INTRODUCTION

Percutaneous vertebroplasty consists of the injection of acrylic cement into weakened vertebral bodies to achieve pain relief and mechanical stability of the spine.

OBJECTIVE

To evaluate the characteristics and effectiveness of the vertebroplasties performed at the Hospital Universitario Miguel Servet in Zaragoza.

PATIENTS AND METHODS

This is a retrospective study of 147 vertebroplasties performed in 95 patients (60 women and 35 men; age range: 19 to 84 years). The oblique transpedicular approach, which achieves adequate cement injection with a single puncture, is currently used. A visual analogue scale (VAS) was used to evaluate pain before and after the procedure.

RESULTS

The osseous lesion most often treated by vertebroplasty is fracture secondary to osteoporosis, accounting for 65% of the cases in this series, followed by hemangiomas (23%), and osteolytic metastases, traumatic fractures, lymphomas, and myelomas. Prior to vertebroplasty, the mean VAS score was 8.88 versus 2.78 after the treatment. Only 7.3% of the patients had symptomatic complications.

CONCLUSION

Vertebroplasty is safe and efficacious; it is the treatment of choice for vertebral pain refractory to medication. It enables patients to return to their habitual lifestyle quickly and thus helps reduce hospital stays and costs.

Glycosylation and sorting pathways of lysosomal enzymes in mussel digestive cells

Our aim was to contribute to the understanding of the synthesis, maturation and activation of lysosomal enzymes in an invertebrate cellular model: the endo-lysosomal system (ELS) of mussel digestive cells. The activities of 5'-nucleotidase (AMPase), arylsulphatase (ASase) and acid phosphatase (AcPase), which are transported towards acidic compartments as membrane proteins, were localised by enzyme cytochemistry. AcPase activity was found within large heterolysosomes and residual bodies. ASase was located in endosomes, endolysosomes and heterolysosomes. AcPase and ASase activities were recorded within small vesicles and cisterns of the trans-Golgi network. Conversely, AMPase activity was primarily found in microvilli and apical vesicles and, less conspicuously, in lysosomes and the cis-side of the Golgi and the cis-Golgi network (CGN). In order to understand the processes of synthesis and maturation of these lysosomal enzymes, selected glycoconjugates were localised after lectin cytochemistry. N-acetylglucosamine, mannose and fucose residues were almost ubiquitous in the ELS, as were galactose residues, which were apparently less abundant. N-acetylglucosamine residues occurred in the inner membrane co-localised with mannose residues within the lysosomal and pre-lysosomal acidic compartments. Based on these results, glycosylation and sorting pathways are proposed for both soluble and membrane enzymes. Unlike in mammalian cells, O-glycosylation is fully completed in the CGN, mannose addition in N-glycosylation extends beyond the CGN and galactose addition is fully achieved at the intermediate side. Sorting of soluble lysosomal enzymes, as in crustaceans, is mediated by the indirect transport of membrane-linked proteins with GlcNAc1-P6Man residues that are removed in endolysosomes and heterolysosomes.

Assessment of potential interactions between phytase and glycosidase enzyme supplementation on nutrient digestibility in broilers

The effects of microbial 3-phytase and glycosidase enzymes, and their interactions, on energy values and nutrient digestibility in diets rich in nonstarch polysaccharides (NSP) were studied in diets based on corn, wheat, or barley. Four diets were prepared with each cereal grain. One had no enzymes, a second had 500 units of phytase, a third had glycosidase enzyme, and a fourth had phytase and glycosidase. The glycosidases used were alpha-galactosidase (corn diet), xylanase (wheat), and beta-glucanase (barley). Glycosidase decreased intestinal viscosity, whereas phytase increased this parameter in corn diets. Phytase increased AME in corn diets, whereas beta-glucanase in barley diets improved AME and AMEn, and digestibility of dry matter, starch, beta-glucans, and lipid. Xylanase in wheat diets improved dry matter and starch digestibility. Phytase increased total phosphorus retention in all diets, and significant interactions between glycosidase enzymes and phytase were detected in wheat and barley diets. Phytase decreased phosphorus excretion in corn and barley diets, whereas alpha-galactosidase increased phosphorus excretion in corn diets. Phytase in corn diets and beta-glucanase in barley diets increased calcium retention, whereas inclusion of xylanase decreased calcium retention in wheat diets. Phytase and beta-glucanase decreased calcium excretion in corn- and barley-based diets, respectively. An interaction was detected between phytase and beta-glucanase in barley diets, in which calcium excretion was reduced. In general, no negative interactions between phytase and glycosidase enzymes were found, indicating that both types of enzymes may be used together in feeds based on corn, wheat, or barley.

Comparative effects of fosinopril and irbesartan on hematopoiesis in essential hypertensives

OBJECTIVE

To compare the response of erythropoiesis to an angiotensin receptor blocker, irbesartan with an angiotensin conversing enzyme inhibitor, fosinopril, in essential hypertensive patients with normal renal function.

DESIGN AND METHODS

Thirty patients were randomized to receive either irbesartan (150 mg once daily) (n = 15, mean age 65.2+/-8.7 years) or fosinopril (20 mg once daily) (n = 15, mean age 57.4+/-11.5 years, difference is not significant) during 12 weeks. Plasma erythropoietin, hemoglobin (Hb) and hematocrit (Hc) levels were measured at start and monthly after receiving the treatment. All values are expressed as mean+/-1SD.

RESULTS

Irbesartan decreased erythropoietin levels (baseline 20.7+/-1.3 vs. 18.1+/-3.7 mU/mL, p=0.019), but they remained unchanged with fosinopril (baseline 18.8+/-1.3 vs. 18.6+/-1.6 mU/mL). Hb levels lowered in irbesartan group (baseline 13.8+/-1.2 vs. 13.5+/-1.1 g/dL, p=0.029), but they did not change in fosinopril-treated patients (baseline 14.6+/-1.3 vs. 14.5+/-1.3 g/dL). Hc did not show any change neither in irbesartan group (baseline 40.9+/-3.7 vs. 40.8+/-3.3 %) nor in fosinopril group (baseline 14.6+/-1.3 vs. 14.5+/-1.3 %).

CONCLUSIONS

Irbesartan lowered erythropoietin secretion and hemoglobin levels in essential hypertensives. Fosinopril can neither influence erythropoietin secretion nor decrease hemoglobin levels. Angiotensin receptor blockers seem to get higher efficacy for antagonism angiotensin effects. Safety of angiotensin receptor blockers in anemic hypertensive patients should be studied.

The presence of nicotinamide adenine dinucleotide-independent Haemophilus paragallinarum in México

Two isolates of Haemophilus paragallinarum were obtained from a layer chicken in Mexico. The isolates were confirmed as H. paragallinarum by polymerase chain reaction and conventional biochemical identification. The isolates were nicotinamide adenine dinucleotide (NAD) independent-growing on blood agar without the need of a nurse colony as well as on a complex medium that lacked both NAD and chicken serum. Both isolates were pathogenic, causing the typical clinical signs of infectious coryza in susceptible chickens. One isolate was Page serovar B/Kume serovar B-1 and the other isolate was Page serovar C/Kume serovar C-2. The isolates were associated with a field outbreak that involved an egg drop of 20% over a 3-wk period and a doubling of weekly mortality (from 0.1% to 0.2%). This is the first report of NAD-independent H. paragallinarum outside South Africa and is the first time that NAD-independent H. paragallinarum of serovar B has been reported.

[Hypothalamic-infundibular histiocytosis: magnetic resonance findings]

INTRODUCTION

We report the magnetic resonance imaging (MRI) of a case of Langerhans cell histiocytosis in the pituitary. Isolated central nervous system involvement is uncommon.

CASE REPORT

An eighteen-years old female patient who had an acute onset of central diabetes insipidus because of the Langerhans cell histiocytosis. The MRI evidenced a lesion in the hypothalamic-pituitary axis. The hyperintensity in the posterior pituitary lobe, which is seen in normal subjects on T1-weighted images, was absent. The pituitary stalk was thickened and enhanced homogeneously following contrast administration. During the follow-up, the infundibullar lesion extended to the hypothalamic region and other systemic manifestations appeared. Diagnosis of Langerhans cell histiocytosis was confirmed by lung biopsy. After radiotherapy and chemotherapy, MRI showed regression of the hypothalamic-pituitary lesion.

CONCLUSION

The combination of these findings, although nonspecific of Langerhans cell histiocytosis, should nevertheless prompt further studies, including chest films, bone scanning and temporal bone computerized tomography in order to narrow the differential diagnosis.

[Evaluation of lercanidipine in the general practice setting]

OBJECTIVE

To determine the efficacy and tolerability of a long-acting dihydropyridine in the clinical settings of general practice.

MATERIAL AND METHODS

110 essential hypertensives were included (age 62.3 +/- 10.8 years, 51 men and 53 women, 38/ obese -IMC >30 kg/m2, ten diabetics). 104 patients ended the followup. Patients were treated with lercanidipine 10 mg once daily in the morning. Follow-up lasted 6 months. When blood pressure was not controlled (BP < 140/90 mmHg) in any visit, a second drug was added, excluding calcium channel blockers. Antiadrenergic drugs were recommended. If patients were not controlled ittwo consecutive visits they were excluded from follow-up.

RESULTS

Significant reductions in both systolic (baseline 157.4 +/- 11.7 vs 131.1 +/- 6.8 mmHg, p < 0,001) and diastolic BP (baseline 94.7 +/- 5.8 vs 80.0 +/- 5.5 mmHg, p < 0,001) were attained at six months. Mean SBP decrease was 26.7 mmHg and mean DBP reduction was 15.6 mmHg. At the study end, 84.3/ of the patients achieved a BP < 140/90 mmHg. Thirty patients needed a second drug to become controlled (26 at the study end). The overall incidence of adverse effects was 4,4/ (n=6) and just three patients withdrew the treatment due to untoward effects. Plasmatic cholesterol lowered from 225.3 +/- 41.0 to 216.7 +/- 25.3 mg/dl (p = 0,03) and urate decreased from 5.6 +/- 1.6 to 5.1 +/- 1.4 mgldl, p = 0,03).

CONCLUSIONS

Lercanidipine is a calcium channel blockers of high efficacy and low incidence of adverse effects in the clinical settings of general practice. It seems to have a positive metabolic effects on plasmatic levels of cholesterol and urate.

First synthesize new viruses then regulate their release? The case of the wild rabbit

European wild rabbits originated in southwestern Europe but have been introduced into many other countries world-wide, becoming serious pests in many instances. As a consequence of rabbits being regarded so differently, applied research for their management often has opposing goals, namely their conservation or their control. Furthermore, modern gene technology has led to the concept of using genetically modified myxoma viruses for rabbit management, again with quite contrary aims in mind. In this paper we explain the possible ecological and economic consequences of using these genetically modified viruses inappropriately and we consider whether national and international regulations are sufficient to prevent improper use. If international regulations are inadequate, molecular biologists and ecologists must consider the consequences of their research and advice beyond their own country to avoid unwanted impacts.

[Comparison of the antihypertensive activity of fosinopril and irbesartan]

OBJECTIVE

To compare the antihypertensive effect of two daily single dose drugs acting on the renin-angiotensin axis by two different ways.

METHODS

Thirty patients were randomized to receive either irbesartan (150 mg once daily) (n = 15, mean age 65.2 +/- 8.7 years, 9 men and 6 women) or fosinopril (20 mg once daily) (n = 15, mean age 57.4 +/- 11.5 years, 4 men and 11 women, difference are not significant) during 12 weeks. When needed, hydroclorothiazide (12.5 mg) was added to treatment to improve hypotensive response.

RESULTS

A reduction of SBP and DBP was observed in both treatment groups throughout the study. In order to obtain further BP reduction, hydrochlorothiazide was added to 6 patients with inadequate BP response at the 4th week (3 patients in the irbesartan group) and 8th week (2 patients in irbesartan group and 1 patient in fosinopril group). SBP was reduced in irbesartan group from 157.7 +/- 11.2 to 131.0 +/- 8.7 mmHg (12th week, p < 0.001). DBP decreases from 94.1 +/- 5.6 to 82.7 +/- 4.2 mmHg (p < 0.001). In fosinopril group SBP was reduced from 147.9 +/- 11.7 to 132.2 +/- 12.4 mmHg (p < 0.001) and DBP decreases from 92.3 +/- 6.3 to 84.0 +/- 5.4 mmHg (p < 0.001). Final between group differences in BP are not significant. Final BP reduction in irbesartan group (26.7 +/- 11.6 mmHg) was bigger than that obtained in fosinopril group (15.6 +/- 11.6 mmHg, p = 0.011). BP reduction was significant in fosinopril group from the first month (SBP 140.7 +/- 12.2, p = 0.021; DBP 87.2 +/- 6.2, p = 0.003). In irbesartan group BP reduction was not significant until the second month (SBP 135.5 +/- 10.4, p < 0.001; DBP 85.3 +/- 4.3, p < 0.001).

CONCLUSIONS

Fosinopril and irbesartan seems to be equally effective to reduce DBP. Irbesartan might have higher effectiveness on systolic blood pressure. Irbesartan act more gradually than fosinopril and this may be useful to prevent from acute blood pressure falls.

Metabotropic glutamate 1alpha and adenosine A1 receptors assemble into functionally interacting complexes

Recently, evidence has emerged that seven transmembrane G protein-coupled receptors may be present as homo- and heteromers in the plasma membrane. Here we describe a new molecular and functional interaction between two functionally unrelated types of G protein-coupled receptors, namely the metabotropic glutamate type 1alpha (mGlu(1alpha) receptor) and the adenosine A1 receptors in cerebellum, primary cortical neurons, and heterologous transfected cells. Co-immunoprecipitation experiments showed a close and subtype-specific interaction between mGlu(1alpha) and A1 receptors in both rat cerebellar synaptosomes and co-transfected HEK-293 cells. By using transiently transfected HEK-293 cells a synergy between mGlu(1alpha) and A1 receptors in receptor-evoked [Ca(2+)](i) signaling has been shown. In primary cultures of cortical neurons we observed a high degree of co-localization of the two receptors, and excitotoxicity experiments in these cultures also indicate that mGlu(1alpha) and A1 receptors are functionally related. Our results provide a molecular basis for adenosine/glutamate receptors cross-talk and open new perspectives for the development of novel agents to treat neuropsychiatric disorders in which abnormal glutamatergic neurotransmission is involved.

Acute and acclimated digestive responses of the cockle Cerastoderma edule (L.) to changes in the food quality and quantity. II. Enzymatic, cellular and tissular responses of the digestive gland

Cockles Cerastoderma edule were fed two different concentrations of two diets with different qualities which were achieved by mixing different proportions of ashed silt particles with cells of the microalgae Tetraselmis suecica. After 3 days (acute response) and 11 days (acclimated response) of exposure to the diets, we analysed the digestive activity of the digestive gland using cyto-histological and enzymatic techniques. We measured (i) the volumetric fraction of digestive and basophilic cells in digestive tubules, (ii) the diverticular radius and the thickness of digestive epithelia, (iii) the stereological parameters characterizing the lysosomal system and, (iv) dry weight, soluble protein content and specific and total amylase, cellulase, laminarinase, and protease activities of the digestive gland. In the conditions of the present study, specific cellulase and laminarinase activities in the digestive gland of cockles were correlated with the volumetric fraction of basophilic cells (r=0.672 and 0.642, respectively), whereas the specific protease was highly correlated (r=0.866) with lysosomal volume density. The implications of these correlations are discussed in relation to the feeding and absorptive parameters reported in the preceding publication. In the acute response, adjustments of the synthesis of constituents of the lysosomal/proteolytic system of the digestive cells seemed to be the only mechanism operating at the digestive level to respond to the changes in food availability. Lysosomal volume density increased with rising ingestion rate of organic matter, however, the occurrence of a limit in this short-term tissular response would account for the recorded trade-off between absorption efficiency and ingestion rate with different food qualities. With regard to acclimation, food quality determined the nature of the response of the digestive gland. With low quality diets, a time-dependent capability of the digestive gland for intensifying lysosomal/proteolytic production explains the increase of food absorption rates that result from higher filtration and ingestion rates. With high quality food, digestive acclimation differed with food particle concentration: with low rations, in spite of constant morphometrical and stereological parameters, the significant changes in the absorptive balance of biochemical components suggests the existence of an increased production of lysosomes that promotes an accelerated turn-over rate of the digestive epithelia. With high food concentrations, this response was coupled with increased activities of cellulase and laminarinase enzymes, probably as a consequence of higher rates of enzyme secretions from basophilic cells.

Deriving ecological risk-based soil quality values in the Basque Country

Most industrialised countries are currently drawing up their procedures to deal with contaminated land. In the Basque Country generic soil quality values applicable to different land uses have been drawn up for many common soil inorganic and organic pollutants, to assist in the site assessment process. In this paper we present those values aimed at protecting ecosystems as the main target at risk. Ecological risk was defined on the basis of effects on the structure of the soil invertebrate community. Ecotoxicological data from laboratory tests were used in combination with a theoretical extrapolation method. The following groups of compounds were assayed: heavy metals, cyanides, aromatic compounds, polycyclic aromatic hydrocarbons, HCH isomers, chlorinated organic compounds, and mineral oil. A specific toxicity database was created. The reliability of the values obtained as well as the limitations of the derivation process are discussed.

The use of two species of crayfish as environmental quality sentinels: the relationship between heavy metal content, cell and tissue biomarkers and physico-chemical characteristics of the environment

In systems as heavily disturbed as rivers, the use of biological sentinels is a most interesting way of obtaining continuous assessment of environmental quality. This study seeks to establish the value of such sentinels of two species of crayfish: the native crayfish (Austropotamobius pallipes, Lereboullet 1858) and an introduced species, signal crayfish (Pacifastacus leniusculus, Dana 1852), by comparing the habitat quality (water and sediments) and heavy metal contents in crayfish with the degree of stress manifested by the animals, measured by cell and tissue biomarkers. For this purpose a histological study of the digestive gland was carried out together with measurements of heavy metal contents in samples from various points of the river network of Bizkaia (Spain), selected on the basis of their degree of disturbance. The results establish a positive correlation between these environmental conditions, the cell and tissue biomarkers of the digestive gland (thinning of the digestive epithelium, enlargement of digestive lysosomes) and the heavy metal contents of the animals (converted to an index of pollutant load).

Regression study of environmental quality objectives for soil, fresh water, and marine water, derived independently

A regression study among environmental quality objectives on soil, marine and fresh water is studied, considering toxicity data on ecological representative species of invertebrates. The study was carried out by comparing VIE-C values, as defined by E. Angulo and A. Urzelai (1994, in Plan Director para la Protección del Suelo. Calidad del Suelo. Valores Indicativos de Evaluacion, pp. 121-184. IHOBE, Bilbao). To derive these VIE-C values, no-observed-effect concentrations from chronic single-species assays that consider relevant parameters in population dynamics are used. The calculations follow the method of N. M. van Straalen and C.A.J. Denneman (1989, Ecotoxicol. Environ. Saf. 18, 241-251). Equations relating long-term toxicity data of fresh/marine waters, soil/marine water, and soil/fresh water for five metals (Cd, Cu, Hg, Pb, and Zn) are calculated, indicating good correlation between environments: 0.85, 0.78, and 0.89, respectively. On the basis of these results this approach may be useful to obtain soil quality criteria values from other environmental compartments, when soil data are not available.

Autometallographic localization of protein-bound copper and zinc in the common winkle, Littorina littorea: a light microscopical study

Copper (Cu), zinc (Zn) and calcium (Ca) were demonstrated histochemically by means of conventional stains (rubeanic acid for copper, dithizone for zinc, and cobalt nitrate for calcium) and by autometallography in various tissues of winkles (Littorina littorea) sublethally exposed to either copper or zinc dissolved in sea water. Rubeanic acid and dithizone procedures exhibited poor sensitivity: there was no positive reaction after fixation tissues with Bouin's fixative, and only a weak reaction after ethanol fixation. Autometallography, however, produced a positive reaction with both fixatives in the form of black silver deposits in some key cell types. In winkles not exposed to either copper nor zinc, autometallographically demonstrated metals were found in the connective tissue pore cells, the lysosomes of digestive cells, the basal lamina of the digestive tubule epithelium, and cytoplasmic granules in the epithelial cells of the stomach wall. In addition, in winkles exposed to copper, metal deposits were present in some apical cytoplasmic granules of ciliated cells in the gill epithelium, the mucous secretion of gill mucocytes, and the circulating haemocytes. In winkles exposed to zinc, metal deposits were found in the basal cytoplasmic granules of ciliated cells in the gill epithelium, the mucous secretion of gill mucocytes, the apex and basal lamina of the nephrocytes in the kidney, and the connective tissue layer surrounding the blood vessels. Additionally, calcium was demonstrated histochemically in the cytoplasm of digestive cells, the cytoplasm of the epithelial cells of the stomach wall, the mucocytes of gills, the basal lamina of the kidneys, the haemocytes, the calcium and pore cells of connective tissue, and the oocyte cytoplasm. Metals were not detected by any procedure in sperm cells, in the cytoplasmic granules of oocytes, or in the basophilic cells in the digestive tubules. In conclusion, autometallography is a highly sensitive method and provides an excellent tool to localize protein-bound copper and zinc in molluscan tissues, and its use in combination with conventional histochemical or chemical methods is highly recommended.

Light microscopic catalase histochemistry in mussel digestive gland tissue

Different light microscopical procedures for the histochemical demonstration of catalase were tested in cryostat sections of mussel digestive gland tissue by using both benzidine and diaminobenzidine (DAB) as hydrogen donors. The selected procedure, which was also applied to mouse liver for comparative purposes, consisted of incubation in media containing 0.2% DAB and 0.3% H2O2 at pH 10.4 for 35 min at 42 degrees C. Addition of 0.01 M imidazole to the incubation medium increased the staining intensity of the histochemical procedure. The positive reaction product was localized in epithelial cells lining the digestive tubules and the ducts. The histochemical reaction was inhibited partially by aminotriazole or sodium azide and disappeared completely by omission of H2O2 from the incubation medium. On the other hand, heat resistant non-enzymatic reactions were observed in sites known to contain lipofuscins such as epithelial cells of the gastrointestinal tract and connective tissue brown cells.

Research note: effect of diet density and pelleting on productive parameters of Japanese quail

An experiment was conducted to determine the response of growing Japanese quail to two dietary energy levels, high (3,200 kcal ME/kg) versus low (3,000 kcal ME/kg), and two forms of presentation, mash versus pellet. Seven thousand, two hundred day-old Japanese quail (Coturnix coturnix japonica) were randomly distributed into 24 floor pens containing 300 quail each. The experiment was divided in two phases: starter (until 2 wk of age) and finisher (Days 14 to 33). Weight gain was less (P < .05) for quail fed the low-energy mash diet than for those on other treatments. Feed consumption increased (P < .001) when low-energy and mash diets were fed. Metabolizable energy consumption was greater with the mash diets. Feed conversion improved (P < .001) when high-energy and pelleted diets were fed as compared with low-energy and mash diets, respectively. Results indicated that daily gain and feed conversion of quail fed the low-energy, pelleted diet equaled those of quail fed the high-energy mash diet. Pelleting improved the caloric efficiency of gain by quail. Quail seemed to adjust caloric intake according to the energy level of the diet.

Comparative effects of the water accommodated fraction of three oils on mussels—1. Survival, growth and gonad development

1. Mussels, Mytilus galloprovincialis, were exposed to the water accommodated fraction (WAF) of two crude oils (types Ural and Maya) and of a commercial lubricant oil for 91 days. Synchronous spectrofluorometry showed that the aromatic hydrocarbon composition of the WAFs obtained from the three oils were significantly different (Maya-WAF heaviest, Ural-WAF lightest). 2. No significant mortality occurred in mussels exposed to the WAFs of the two crude oils, while all the animals exposed to lubricant-WAF died after 49 and 77 days in intermediate and high doses respectively. 3. Flesh and shell growth of mussels exposed to the WAFs was reduced significantly with respect to controls as demonstrated by several size, condition and allometric parameters. The response to petroleum hydrocarbon exposure is not dose-dependent, maximal responses being measured in low (Ural) and intermediate (Maya) doses. This seems to depend on a behavioural reaction (shell valve closure) against high doses of pollutants which may avoid the sublethal damage to some extent. 4. Shell abnormalities or changes in shell thickness were not detected. 5. The histological study of gonad tissue revealed that gamete release is retarded and hemocytic infiltration of mature gonad tissue is increased after exposure to low and intermediate doses of the WAFs. On the other hand, spawning is readily induced under exposure to high doses of the WAFs.

Comparative effects of the water accommodated fraction of three oils on mussels—2. Quantitative alterations in the structure of the digestive tubules

1. Mussels have been exposed to the water accommodated fraction (WAF) of Ural and Maya crude oils and of a lubricant oil for 91 days and the digestive gland structure has been studied (a) by planimetry, to calculate the mean epithelial thickness (MET), the mean diverticular radius (MDR) and the mean luminal radius (MLR) of the digestive tubules and (b) by subjective tubule grading, to determine the relative (%) occurrence of the different tubule types found in the digestive gland (holding, absorpting, disintegrating, reconstituting and necrotic tubules). 2. Exposure to the 3 types of WAF leads to lowered MET and MET/MDR values, and concomitant higher MLR/MET values. In the case of lubricant- and Ural-WAF exposures, MDR decreases significantly at increasing exposure-doses. 3. Exposure to oil WAFs leads to decreased percentages of holding and absorpting tubules. This decrease is concomitant with an increase of disintegrating tubules in lubricant- and Ural-WAF exposures, and with an increase of regenerating tubules in the Maya-WAF exposure. 4. The statistical significance of the differences found between control and exposed mussels is better at Day 21 than at any other further sampling day (35, 77 and 91). 5. Multiple correlation coefficients between all the percentages of tubule types and each planimetric parameter present an excellent statistical significance.

Chlamydia-like organisms in digestive and duct cells of mussels from the Basque coast

Chlamydia-like organisms have been detected in digestive cells and duct cells of the digestive gland of mussels, Mytilus galloprovincialis, collected from the Basque coast. The organisms appeared as basophilic inclusion bodies within digestive cells and consisted of elongate initial reticulate bodies and previously undescribed condensed forms, interpreted as intermediate bodies. Of the 414 mussels examined by light microscopy, 5.31% showed this type of infection. A second type of chlamydia-like organism was found in nonciliated duct cells. The microorganisms were found mostly free in duct cells and large elongate reticulate bodies, intermediate condensing forms, and fully condensed elementary bodies were clearly distinguished. No serious histopathological or ultrastructural changes were observed in host cells but evidences of a possible localized metabolic damage within infected digestive cells is presented.

Automated measurement of lysosomal structure alterations in oocytes of mussels exposed to petroleum hydrocarbons

The present study examines the structure of the lysosomal system of mature oocytes in mussels, Mytilus galloprovincialis, after a 21 day exposure to the water accommodated fraction (WAF) of two crude oils (types Ural and Maya) and of a commercial lubricant oil. The automated image analysis indicates that lysosomes, showing cytochemically demonstrable beta-glucuronidase activity, are smaller and much more numerous in oocytes of mussels treated with a 40% dose of Ural- and Lubricant-WAF when compared to controls. It is suggested that the structure of the lysosomal system of oocytes is different from that of somatic cells (i.e., digestive cells) and that budding or "fission" into smaller bodies occurs in oocyte lysosomes under certain petroleum hydrocarbon-exposure conditions. These changes in the lysosomal compartment appear to be associated to the process of gamete release or spawning.

Bioavailability of fluorine in sepiolite for laying hens

The purpose of the present work was to compare the bioavailability of structural fluorine contained in sepiolite and in sodium fluoride for laying hens. Three hundred 27-wk-old laying hens were fed one of three diets: 1) a control based on corn, barley, and soybean meal containing 21 mg/kg of fluorine; 2) a sepiolite diet in which 2% sepiolite replaced 2% barley in the control diet and which contained 217 mg/kg of fluorine; and 3) a NaF diet, consisting of the same control diet to which NaF was added to contain 217 mg/kg of fluorine (the same level of F- as the sepiolite diet). The experiment ended when hens were 64 wk old. Fluorine concentration in the tibial bone of hens fed the NaF diet was four times higher than in the control, and twice as high in eggshell. In contrast, hens fed sepiolite had fluorine concentrations in tibial bone and eggshell not significantly higher than fluorine concentrations in the controls. These results indicate that fluorine from sepiolite was not available. The effects of the different diets on egg production, feed intake, feed conversion, egg weight, shell and interior egg quality, dry matter of feces, and body weight gain were also determined but no significant differences due to the dietary treatment were observed.

Cellular cadmium distribution in the common winkle, Littorina littorea (L.) determined by X-ray microprobe analysis and histochemistry

Various tissues of common winkles, Littorina littorea (L.), experimentally exposed to cadmium (Cd) chloride were examined using light and electron microscopy and their elemental composition determined by X-ray microanalysis and histochemistry. Membrane granules in gill epithelial cells with paddle cilia contain carbonates, phosphates and sulphides associated with different cations in different types of granules. Traces of Cd have been found only in those granules containing sulphur and iron. Nephrocytes also contain small amounts of this metal in the cytoplasm of excretory cells. X-ray microanalysis reveals that concretions of basophilic cells are minor sites for Cd sequestration while BTAN-ASSG stain for unbound Cd indicates that most of the Cd is located within the lysosomes of digestive cells in association with proteins. Low amounts of the metal have been evidenced in the granules of epithelial mantle cells rich in sulphur. The results also indicate that hemocytes contain granules of calcium phosphate and iron sulphide. Cd is also associated to sulphur rather than to phosphate. These hemocytes may act as Cd carrier from gills to kidney and digestive gland. A hypothetical pathway for Cd accumulation and detoxification is suggested.

Entry of DSIP peptides into dog CSF: role of physicochemical and pharmacokinetic parameters

Delta sleep-inducing peptide (DSIP) or one of four DSIP analogs (desTrp-DSIP, D-Ala3-DSIP, D-Ala4-DSIP, D-Ala4-DSIP-NH2), was injected IV into dogs. Samples of cerebrospinal fluid (CSF) from the posterior fossa and blood were collected simultaneously at 2, 5, 10, 20, 30, 45, and 60 min after injection and concentrations of DSIP-like material measured by radioimmunoassay (RIA). The increase in peptide concentration in the CSF correlated significantly with the increase in plasma concentration, with plasma half-life, and with peptide lipophilicity, but not with the degree of plasma protein binding or with molecular weight. An even better correlation occurred when the three factors that correlated independently were combined into a single parameter (r = 0.813, p less than 0.00005). These results demonstrate that peptides can significantly penetrate the blood-CSF barrier of the dog. For DSIP and its analogs, the degree of penetration into the CSF is highly dependent on parameters such as the level of peptide in the plasma, plasma half-life, and the lipophilicity of the peptide.

A histochemical and electron microscopic study on the collagen of nerves in the domestic fowl

The collagen in the endoneurium is present as argyrophilic reticular fibres, which show up as thin, weakly birefringent greenish fibres when studied by aid of the Picrosirius-polarization method, and are composed of loosely arranged thin collagen fibrils. The epineurium consists of thick non-argyrophilic collagen fibres, which display a strong birefringence of red or yellow colour when studied by the aid of the Picrosirius-polarization method, and consist of closely packed thick collagen fibrils. These characteristics strongly suggest that the reticular fibres in the endo- and perineurium are composed mainly of collagen Type III, whereas collagen Type I predominates in the epineurium. The fact that these observations on birds are consistent with the descriptions available in the literature for fish, amphibians, reptiles and mammals, argues in favour of the existence of a uniform structural pattern of collagen distribution that is a general phenomenon in vertebrate nerves.