High pressure homogenization: A promising approach to expand food applications of chia mucilage

Two chia mucilages with different viscosities, obtained by extraction conditions optimized in a previous work, were homogenized by high pressure homogenization (HPH). Particle size, molecular weight, zeta potential, FTIR spectrum, rheological properties, water absorption capacity, water holding capacity and iron binding capacity were determined on both mucilages treated and without treatment. Homogenization led to a significant reduction in viscosity respect to chia mucilage controls, which can be related to the decrease in particle size and molecular weight. A high iron binding capacity was obtained for both mucilages. FTIR spectra of both mucilages with iron showed displacements in bands related with stretching of carboxylic uronic acids, suggesting the interaction site with this mineral. This interaction was also verified by particle size determination with a displacement to higher sizes in the presence of iron. Potential zeta showed a significant reduction in the presence of iron. A model to explain the binding between chia mucilage and iron is proposed. HPH appears as an alternative to expand chia mucilage functionality reducing the viscosity of chia mucilage solutions for the offer of a new ingredient also with optimal levels of hydration and iron binding capacity.

Iron-caseinglycomacropeptide complexes: Characterization and application in beverages

Complexing iron with organic compounds has been considered an alternative strategy to mitigate the problems associated with the level of bioavailable iron and the acceptability of products supplemented with this mineral. CMP contains specific amino acids associated with iron binding. The present study aims to optimize the conditions of Fe/CMP complex formation and understand the molecular basis of interactions between CMP and iron ions. Results showed that CMP can bind ferrous iron in a 1:1.5 M ratio, forming a stable peptide-iron complex, where CMP assembles in a tetrameric form. FTIR spectra indicated that iron binding altered the secondary structures of CMP. The iron-binding sites of CMP corresponded primarily to acid residues of Glu, Asp and sialic acid. Moreover, Fe/CMP complex remained stable in a wide pH range (2.0-6.5), suggesting the adequacy to be efficiently added in food or beverages and to keeping complexed in the digestion environment. Finally, Fe/CMP complex was added to a commercial beverage (2 mg of Fe per serving of beverage) and no changes were observed in their colour during storage. A model to explain the binding between CMP and iron is proposed. These results suggest a potential application of this peptide for iron fortification.

The Role of Fumonisins in the Biological Interaction between Fusarium verticillioides and Sitophilus zeamais

The aim of the current study was to investigate the entomopathogenic capacity of the mold Fusarium verticillioides and the effect of its mycotoxins fumonisins, on the grain beetle Sitophilus zeamais. We evaluated the capacity of this fungus to infect live insects, the antifungal activity of constituents of the insect's epicuticle, and the effect of a fumonisin extract on the fitness of the insects. We found that F. verticillioides could not penetrate the cuticle of S. zeamais and that the fumonisin extract had no negative effects on the fitness of the insects. However, the progeny of the insects increased, and the fumonisin extract had repellent effects. This is the first report about the effects of fumonisins on the relationship between F. verticillioides and S. zeamais, which may provide useful information about interactions between pathogenic microorganisms and insects, especially on stored product pests.

Renal Artery Dissection in a Young Woman: Diagnoses Beyond Fibromuscular Dysplasia

A 31-year-old woman presented at the emergency room after experiencing colic pain in the right iliac fossa for 5 days. She had previously consulted another center, where deterioration of renal function had been identified and abdominal computed tomography (CT) angiography had shown a dissection of the right renal artery, with areas suggestive of infarction in the right kidney, as well as an aneurysm in the left renal artery and a smaller left kidney. The patient had no relevant family or personal history except posttraumatic carotid-cavernous fistula in 2014, which had been treated with embolization. In our hospital, the patient was hypertensive and acute renal failure was confirmed, accompanied by an increase in lactate dehydrogenase and isomorphic microhematuria. After a new CT Scan, in addition to the lesions described in the renal arteries, another aneurysm in the splenic artery and an aneurysm of the right femoral artery were identified. Antihypertensive treatment was initiated with calcium antagonists and anticoagulation. Subsequent renal arteriography confirmed the dissection of the right renal artery, which could not be repaired, and a coated stent was placed in the left renal artery to exclude the aneurysm. The splenic artery lesion was treated 2 months later. The etiological diagnosis in this young woman was challenging. The presence of visceral aneurysms suggested a differential diagnosis comprising fibromuscular dysplasia, vasculitis, and collagenopathies. Using a multidisciplinary approach and directed anamnesis, the presence of frequent sprains, joint hypermobility, and skin fragility was confirmed. Blood immunology and CT angiography including the thoracic and cervical territories were normal. Echocardiography revealed tricuspid insufficiency. All these data suggested the presence of a collagen-like Ehlers-Danlos syndrome (vascular form). The diagnosis was confirmed by the genetic study, which showed a pathogenic mutation in the COL3A1 gene. Currently, the patient is asymptomatic with recovered renal function following treatment with a beta-blocker and antiplatelet therapy.

First Measurement of the Total Neutron Cross Section on Argon between 100 and 800 MeV

We report the first measurement of the neutron cross section on argon in the energy range of 100-800 MeV. The measurement was obtained with a 4.3-h exposure of the Mini-CAPTAIN detector to the WNR/LANSCE beam at LANL. The total cross section is measured from the attenuation coefficient of the neutron flux as it traverses the liquid argon volume. A set of 2631 candidate interactions is divided in bins of the neutron kinetic energy calculated from time-of-flight measurements. These interactions are reconstructed with custom-made algorithms specifically designed for the data in a time projection chamber the size of the Mini-CAPTAIN detector. The energy averaged cross section is 0.91±0.10(stat)±0.09(syst)  b. A comparison of the measured cross section is made to the GEANT4 and FLUKA event generator packages, where the energy averaged cross sections in this range are 0.60 and 0.68 b, respectively.

Positive Predictive Value of Abdominal Sonography in the Diagnosis of Ischemic Colitis

AIM

The aim was to prospectively evaluate the positive predictive value of ultrasound in the diagnosis of ischemic colitis, with colonoscopy as the reference standard.

METHODS

During a 2-year period we included consecutive patients over 50 years of age with sudden abdominal pain and/or rectal bleeding who underwent abdominal sonography in an emergency setting with a thickened segment of colon with a length of more than 10 cm. This clinical-sonographic triad was considered diagnostic for ischemic colitis. A thickened bowel location or color Doppler flow findings on ultrasound examination were evaluated but were not considered to make the diagnosis of ischemic colitis. Basic descriptive statistics were used to characterize the study patients. The positive predictive value was calculated as: number of patients with the definitive diagnosis of ischemic colitis (colonoscopic or follow-up)/number of patients with a sonographic diagnosis of ischemic colitis.

RESULTS

A total of 48 patients had the clinical-sonographic triad; mean age: 74.3 years (range 54-90 years). The most frequent clinical manifestation was rectal bleeding (83% of the cases) followed by abdominal pain (81%) and diarrhea (45%). A total of 42 cases of ischemic colitis were confirmed by endoscopy (n=35) and biopsy (n=34) or clinical evaluation (n=7). The positive predictive value of the clinical-sonographic diagnosis of ischemic colitis was 87.5%. Thickening of the colon wall was detected on the left side in 35 patients with ischemic colitis, on the right side in 3 and pancolitis was identified in 5 patients.

CONCLUSION

In an appropriate clinical setting, ultrasound has a high positive predictive value for the diagnosis of ischemic colitis.

Diagnosis of acute cortical necrosis in renal transplantation by contrast-enhanced ultrasound: a preliminary experience

PURPOSE

To evaluate the use of contrast-enhanced ultrasound (CEUS) for diagnosis of cortical necrosis in renal allografts.

MATERIALS AND METHODS

We reviewed the medical records and imaging studies of five patients who underwent emergency transplantectomy and a histological diagnosis of cortical necrosis in the period between May 2009 and May 2011. US examinations included initially B-mode and color Doppler and then contrast-enhanced ultrasound with low mechanical index after injection of 2.4 ml of a second generation echo-signal enhancer. Renal transplant vascularization was evaluated during a period of 4 minutes including arterial, corticomedullary and nephrographic phases. Radiologic-pathologic correlation was obtained after transplantectomy in all cases.

RESULTS

Five patients with an age range between 30 and 48 years. Post-transplant color Doppler ultrasound showed decreased renal parenchymal vascularization and difficulty to find the spectral waveforms with resistive indexes greater than 0.7 in 4 of 5 patients. CEUS showed enhancement of the main arteries, followed by the enhancement of medullary pyramids, but with an unenhanced peripheral cortical continuous band viewed in all phases, a similar finding to the peripheral rim sign, pathognomonic of cortical necrosis on CT or MRI. The pathologic assessment showed violet kidneys macroscopically with hemorrhagic foci in the outer cortical that drew a well-defined band, findings agreed with CEUS findings.

CONCLUSION

CEUS can show the typical peripheral rim sign in cases of cortical necrosis allowing a reliable and fast diagnosis of this condition and it could obviate further imaging studies or biopsy, allowing an earlier decision of nephrectomy.

Animal models of orthopoxvirus infection

Smallpox was one of the most devastating diseases known to humanity. Although smallpox was eradicated through a historically successful vaccination campaign, there is concern in the global community that either Variola virus (VARV), the causative agent of smallpox, or another species of Orthopoxvirus could be used as agents of bioterrorism. Therefore, development of countermeasures to Orthopoxvirus infection is a crucial focus in biodefense research, and these efforts rely on the use of various animal models. Smallpox typically presented as a generalized pustular rash with 30 to 40% mortality, and although smallpox-like syndromes can be induced in cynomolgus macaques with VARV, research with this virus is highly restricted; therefore, animal models with other orthopoxviruses have been investigated. Monkeypox virus causes a generalized vesiculopustular rash in rhesus and cynomolgus macaques and induces fatal systemic disease in several rodent species. Ectromelia virus has been extensively studied in mice as a model of orthopoxviral infection in its natural host. Intranasal inoculation of mice with some strains of vaccinia virus produces fatal bronchopneumonia, as does aerosol or intranasal inoculation of mice with cowpox virus. Rabbitpox virus causes pneumonia and fatal systemic infections in rabbits and can be naturally transmitted between rabbits by an aerosol route similar to that of VARV in humans. No single animal model recapitulates all known aspects of human Orthopoxvirus infections, and each model has its advantages and disadvantages. This article provides a brief review of the Orthopoxvirus diseases of humans and the key pathologic features of animal models of Orthopoxvirus infections.

Manganese-Mediated Lignin Degradation by Pleurotus pulmonarius

Pleurotus pulmonarius produced the strongest degradation of lignin during solid-state fermentation of [(sup14)C]lignin wheat straw with different fungi. A manganese-oxidizing peroxidase seemed to be involved in lignin attack, since the addition of Mn(sup2+) to the culture increased lignin mineralization by ca. 125%. This enzyme was purified and characterized from both solid-state fermentation and liquid cultures.

Effect of Sex, Ovariectomy and Female Sex Hormones on Neutral Cholesterol Ester Hydrolase in Rat Liver

The effects of sex, ovariectomy and female sex hormones on neutral cholesterol ester hydrolase activity were investigated in rat liver cytoplasm. Hydrolase activity was determined at pH 7.45 with an acetone dispersed cholesterol oleate substrate preparation. Neutral cholesterol esterase activity was higher in male than in female rats and the ovariectomy decreased the enzyme activity. The administration of only estradiol or combined with progesterone to ovariectomized rats for three consecutive days resulted in an increase in esterase activity to the level observed in intact animals. By contrast, the only progesterone resulted in no significant changes of activity. In intact female rats, the short-term treatments of gonadal hormones did not produce any alteration on cholesterol esterase. Examination of the effects of a single dose of estradiol and progesterone for intervals between 1 and 24 h showed that both hormones promoted early and opposite effects on neutral ester hydrolase. Activity was decreased in 3-4 h by the estradiol and was markedly increased throughout 3-4-6 h by the progesterone injection. In vitro, the two female sex hormones behaved as potent inhibitors of the enzyme, competing with the substrate for the active centre of the hydrolase.

Effect of Chia oil (Salvia Hispanica) rich in omega-3 fatty acids on the eicosanoid release, apoptosis and T-lymphocyte tumor infiltration in a murine mammary gland adenocarcinoma

We investigated the effects of certain dietary polyunsaturated fatty acids (PUFAs) and related eicosanoids on the growth and metastasis formation of a murine mammary gland adenocarcinoma. Salvia hispanica (ChO) and Carthamus tinctorius (SaO) vegetable oil sources of omega-3 and -6 PUFAs and a commercial diet as control (CO), were used. We analysed fatty acids of neoplastic cells (NC) membranes by GLC; the eicosanoids 12- HETE and 12-HHT (LOX and COX metabolites) by HPLC and apoptosis and T-lymphocyte infiltration by flow cytometry and microscopy. NC from ChO groups showed lower levels of arachidonic acid and of both eicosanoids compared to SaO and CO (p<0.05). The ChO diet decreased the tumor weight and metastasis number (p<0.05). Apoptosis and T-lymphocyte infiltration were higher and mitosis decreased with respect to the other diets (p<0.05). Present data showed that ChO, an ancient and almost unknown source of omega-3, inhibits growth and metastasis in this tumor model.

Standardised uptake values from PET/CT images: comparison with conventional attenuation-corrected PET

PURPOSE

In PET/CT, CT-derived attenuation factors may influence standardised uptake values (SUVs) in tumour lesions and organs when compared with stand-alone PET. Therefore, we compared PET/CT-derived SUVs intra-individually in various organs and tumour lesions with stand-alone PET-derived SUVs.

METHODS

Thirty-five patients with known or suspected cancer were prospectively included. Sixteen patients underwent FDG PET using an ECAT HR+scanner, and subsequently a second scan using a Biograph Sensation 16PET/CT scanner. Nineteen patients were scanned in the reverse order. All images were reconstructed with an iterative algorithm (OSEM). Suspected lesions were grouped as paradiaphragmatic versus distant from the diaphragm. Mean and maximum SUVs were also calculated for brain, lung, liver, spleen and vertebral bone. The attenuation coefficients (mu values) used for correction of emission data (bone, soft tissue, lung) in the two data sets were determined. A body phantom containing six hot spheres and one cold cylinder was measured using the same protocol as in patients.

RESULTS

Forty-six lesions were identified. There was a significant correlation of maximum and mean SUVs derived from PET and PET/CT for 14 paradiaphragmatic lesions (r=0.97 respectively; p<0.001 respectively) and for 32 lesions located distant from the diaphragm (r=0.87 and r=0.89 respectively; p<0.001 respectively). No significant differences were observed in the SUVs calculated with PET and PET/CT in the lesions or in the organs. In the phantom, radioactivity concentration in spheres calculated from PET and from PET/CT correlated significantly (r=0.99; p<0.001).

CONCLUSION

SUVs of cancer lesions and normal organs were comparable between PET and PET/CT, supporting the usefulness of PET/CT-derived SUVs for quantification of tumour metabolism.

Phlebotonics for venous insufficiency

BACKGROUND

Chronic venous insufficiency (CVI) is a common condition caused by inadequate blood flow through the veins, usually in the lower limbs. It can result in considerable discomfort with symptoms such as pain, itchiness and tiredness in the legs. Sufferers may also experience swelling and ulcers. Phlebotonics are a class of drugs that are often used to treat CVI.

OBJECTIVES

To assess the efficacy of oral or topical phlebotonics.

SEARCH STRATEGY

We searched the Cochrane Peripheral Vascular Diseases Group trials register (April 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2005), MEDLINE (January 1966 to April 2005), EMBASE (January 1980 to April 2005) and reference lists of articles. We also contacted pharmaceutical companies.

SELECTION CRITERIA

Randomised, double blind, placebo-controlled trials (RCTs) assessing the efficacy of rutosides, hidrosmine, diosmine, calcium dobesilate, chromocarbe, centella asiatica, disodium flavodate, french maritime pine bark extract, grape seed extract and aminaftone in CVI patients at any stage of the disease.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed trial quality. The effects of treatment were estimated by relative risk (RR) or by standardised mean differences (SMD) by applying a random effects statistical model. Sensitivity analyses were also performed.

MAIN RESULTS

Fifty-nine RCTs of oral phlebotonics were included, but only 44 trials involving 4413 participants contained quantifiable data for the efficacy analysis: 23 of rutosides, ten of hidrosmine and diosmine, six of calcium dobesilate, two of centella asiatica, one of french maritime pine bark extract, one of aminaftone and one of grape seed extract. No studies evaluating topical phlebotonics, chromocarbe, naftazone or disodium flavodate fulfilled the inclusion criteria. Outcomes included oedema, venous ulcers, trophic disorders, subjective symptoms (pain, cramps, restless legs, itching, heaviness, swelling and paraesthesias), global assessment measures and side effects. The results of many variables were heterogeneous. Phlebotonics showed some global benefit (i.e. oedema reduction) (relative risk 0.72, 95% confidence interval 0.65 to 0.81). The benefit for the remaining CVI signs and symptoms must be evaluated by phlebotonic group. There were no quantifiable data on quality of life.

AUTHORS' CONCLUSIONS

There is not enough evidence to globally support the efficacy of phlebotonics for chronic venous insufficiency. There is a suggestion of some efficacy of phlebotonics on oedema but this is of uncertain clinical relevance. Due to the limitations of current evidence, there is a need for further randomised, controlled clinical trials with greater attention paid to methodological quality.

Radioisotopes for metastatic bone pain

BACKGROUND

Bone metastases manifest through pain, which can arise even before the injury is radiologically detected. Pain occurs as a result of bone destruction and, as more destruction ensues, more pain can be experienced. Radiculopathies, plexopathies and shrinkage of spinal nerves due to tumour growth and fractures are very frequent in these patients. Relief of pain from bone metastasis can be achieved by treating the cancer itself; radiotherapy; conventional analgesics; and specific drugs that work on the bone tumour-induced alteration: biphosphonates, calcitonin or radioactive agents.

OBJECTIVES

To determine the efficacy of radioisotopes to control metastatic pain in patients with bone metastases and complications due to bone metastases (hypercalcaemia, bone fracture and spinal cord compression) as well as its efficacy in terms of patient survival and adverse effects.

SEARCH STRATEGY

Randomised and controlled clinical trials related to this review were retrieved electronically using MEDLINE (1966-2003), EMBASE (1974-2003) and Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 1 2003). general strategies to identify RCTs were combined with specific commands to identify trials of radioisotopes and metastatic bone pain.

SELECTION CRITERIA

The inclusion criteria were: randomised trials of patients with metastatic bone pain that compared treatment with radioisotopes and placebo, and where the major outcome was either pain or complications of bone metastases (eg, hypercalcaemia, bone fracture, spinal cord compression) assessed at least four weeks after treatment.

DATA COLLECTION AND ANALYSIS

The quality of included studies was assessed using the Jadad scale and the Oxford Pain Validity Score. Two independent reviewers extracted the data and completed a standard form designed for that purpose. An intention-to-treat analysis was performed, and global estimates of effect were calculated using a random effects model.

MAIN RESULTS

Four trials (325 patients) provided data that suggest a small effect of radioisotopes on pain control both at short and medium term (one to six months). No evidence was available to assess long-term effects (12 months). Only one study provided data on analgesia use and concluded that patients given either radioisotopes or placebo showed similar levels of analgesic use when compared to baseline use. Leukocytopenia and thrombocytopenia are secondary effects associated with the administration of radioisotopes. The incidence of leukocytopenia is significantly greater in patients treated with radioisotopes (RR=4.56, 95% CI (1.22,17.08)). There were also a greater number of thrombocytopenia events in the treatment group, without reaching statistical significance.

REVIEWER'S CONCLUSIONS

The efficacy of radioisotopes has been assessed in clinical trials with small sample sizes and short-term evaluations of the outcomes. There is some evidence indicating that radioisotopes may give complete reduction in pain over one to six months with no increase in analgesic use, but adverse effects, specifically leukocytopenia and thrombocytopenia, have also been experienced.

Calcitonin for metastatic bone pain

BACKGROUND

Pain is the most frequent symptom experienced by cancer patients, its intensity dependent on the site of the tumour. Tumours that compromise bone or nervous structures due to the bone destruction process are the most painful. There are several treatments to deal with pain (and other symptoms) caused by bone metastasis. The hormone, calcitonin, has the potential to relieve pain, and also retain bone density, thus reducing the risk of fractures.

OBJECTIVES

To assess the effectiveness of calcitonin in controlling metastatic bone pain and reducing bone complications (hypercalcemia, fractures and nervous compression) in patients with bone metastases.

SEARCH STRATEGY

Electronic searches were performed in MEDLINE (1966-2001), EMBASE (1974-2001), the Cochrane Central Register of Controlled Trials (Issue 2, 2001), specialised registers of the Cochrane Cancer Network and of the Cochrane Pain, Palliative and Supportive Care Group. Registers of clinical trials in progress were also searched.

SELECTION CRITERIA

Studies were included if they were randomised, double-blind clinical trials of patients with metastatic bone pain, treated with calcitonin, where the major outcome measure was pain, assessed at four weeks or longer.

DATA COLLECTION AND ANALYSIS

Study selection and data extraction were performed by two independent reviewers. Only two studies (90 patients) were eligible for inclusion in the review and therefore meta-analysis of the data was not possible. Intention-to-treat analysis was performed by imputing all missing values as adverse outcomes.

MAIN RESULTS

Of the two small studies included in the review, one study showed a non-significant effect of calcitonin in the number of patients with total pain reduction (RR 2.50; CI 95%, 0.55 to 11.41). The second study provided no evidence that calcitonin reduced analgesia consumption (RR 1.05; CI 95%, 0.90 to 1.21) in patients with painful bone metastases. There was no evidence that calcitonin was effective in controlling complications due to bone metastases; for improving quality of life; or patients' survival. Although not statistically significant, a greater number of adverse effects were observed in the groups given calcitonin in the two included studies (RR 3.35, CI 95%, 0.72 to 15.66).

REVIEWER'S CONCLUSIONS

The limited evidence currently available for systematic review does not support the use of calcitonin to control pain from bone metastases. Until new studies provide additional information on this treatment, other therapeutic approaches should be considered.

Environmental and physiological factors affecting lead and cadmium levels in deciduous teeth

Shed deciduous teeth lead and cadmium content of children from Cartagena (Spain) was assessed. Parents were provided with an interview containing different questions concerning family socioeconomic status, child's health history, zone of residence, or home antiquity. Besides, physiological variables were considered, i.e., sex of donor, presence of caries, type of tooth donated, tooth weight, age of shedding, and position within the mouth. Tooth lead and cadmium data showed a positively skewed distribution and were log-normalized for further analyses. No statistically significant differences could be observed for lead and cadmium values according to the sex of donor. Both heavy metals decreased in content from incisors to molars and with age of shedding. The one-way analysis of variance (ANOVA) displayed both environmental and physiological risk factors contributing to high tooth lead and cadmium values. When a multifactor ANOVA was carried out, the associations between home antiquity, nail biting habit, and jaw with tooth lead levels, as well as those between zone of residence and tooth cadmium levels were found to persist. However, the only common factor for both heavy metals in the multiple analyses was the type of tooth.

Spontaneous complex pheochromocytoma in a Fischer 344 rat

A spontaneous complex pheochromocytoma was diagnosed in the adrenal gland of an aged female Fischer 344 rat. This expansile neoplasm consisted of pheochromocytoma and areas of ganglioneuroma. The supporting stroma of both neoplastic components contained spindle-shaped cells, which also formed large fascicles. Immunohistochemically, pheochromocytoma cells stained for synaptophysin and chromogranin, scattered ganglioneuroma cells stained for neurofilament protein, and the spindle-shaped stromal cells were positive for S-100 protein. Special stains demonstrated Nissl substance in the ganglioneuroma cells and nerve fibers in the fascicles.

Hyperostotic macrodactyly and lipofibromatous hamartoma of the median nerve associated with carpal tunnel syndrome

A new case with 14-year follow-up of an extremely rare variety of congenital hand macrodactyly is presented. The disease characteristically presents a diffuse proliferation of fibrofatty tissue, but in this special type, osteocartilaginous deposits around the joints can also be found. The case presented included the troublesome feature of a lipofibromatous hamartoma in the median nerve at the wrist and its branches producing carpal tunnel syndrome. The patient obtained benefit from carpal tunnel release and epineurolysis. The hyperostotic development was managed with conservative resection of the periarticular osteochondromas. The literature reviewed suggests that the hyperostotic cases of macrodactyly do not differ from general cases of this congenital condition, except for the osteochondral deposits. These tumours develop during adulthood or after previous trauma, before epiphyseal closure.

Failure to incriminate domestic flies (Diptera: Muscidae) as mechanical vectors of Taenia eggs (Cyclophyllidea: Taeniidae) in rural Mexico

Flies caught in homes in a rural village in Guerrero, Mexico, between November 1994 and August 1995 were assessed for their role in the transmission of Taenia solium L. Most (99%) of the trapped flies were Musca domestica L. None of the 1,187 guts or 1,080 legs of the flies contained T. solium eggs. Pigs roam freely in this village consuming human fecal material immediately after defecation, thereby limiting fly contact with T. solium eggs.

Parental origin and mechanisms of formation of cytogenetically recognisable de novo direct and inverted duplications

Cytogenetic, FISH, and molecular results of 20 cases with de novo tandem duplications of 18 different autosomal chromosome segments are reported. There were 12 cases with direct duplications, three cases with inverted duplications, and five in whom determination of direction was not possible. In seven cases a rearrangement between non-sister chromatids (N-SCR) was found, whereas in the remaining 13 cases sister chromatids (SCR) were involved. Paternal and maternal origin (7:7) was found almost equally in cases with SCR (3:4) and N-SCR (4:3). In the cases with proven inversion, there was maternal and paternal origin in one case each. Twenty three out of 43 cytogenetically determined breakpoints correlated with common or rare fragile sites. In five cases, including all those with proven inverse orientation, all breakpoints corresponded to common or rare fragile sites. In at least two cases, one with an interstitial duplication (dup(19)(q11q13)) and one with a terminal duplication (dup(8) (p10p23)), concomitant deletions (del(8) (p23p23.3) and del(19)(q13q13)) were found.

Saccharomyces cerevisiae PAU genes are induced by anaerobiosis

Saccharomyces cerevisiae PAU genes constitute the largest multigene family in yeast, with 23 members located mainly in subtelomeric regions. The role and regulation of these genes were previously unknown. We detected PAU gene expression during alcoholic fermentation. An analysis of PAU gene regulation using PAU-lacZ fusions and Northern analyses revealed that they were regulated by anaerobiosis. PAU genes display, however, different abilities to be induced by anaerobiosis and this appears to be related to their chromosomal localization; two subtelomeric copies are more weakly inducible than an interstitial one. We show that PAU genes are negatively regulated by oxygen and repressed by haem. Examination of PAU gene expression in rox1Delta and tup1Delta strains indicates that PAU repression by oxygen is mediated by an unknown, haem-dependent pathway, which does not involve the Rox1p anaerobic repressor but requires Tup1p. Given the size of the gene family, PAU genes could be expected to be important during yeast life and some of them probably help the yeast to cope with anaerobiosis.

A mouse model of aerosol-transmitted orthopoxviral disease: morphology of experimental aerosol-transmitted orthopoxviral disease in a cowpox virus-BALB/c mouse system

OBJECTIVES

To determine the morphologic changes and disease progression of aerosolized cowpox virus infection in BALB/c mice and to ascertain the suitability of cowpox virus-infected BALB/c mice as a model of aerosol-transmitted, orthopoxviral respiratory disease.

METHODS

BALB/c mice were inoculated with cowpox virus, Brighton strain, by aerosol or intranasal route. Mice were killed at specified times after inoculation, necropsied, and tissues were collected for routine histology, immunohistochemistry, and electron microscopy.

RESULTS

Inoculation by both routes resulted in disease and death. Immunolabeled viral antigen and lesions predominated in the tissues associated with the inoculation route, that is, lungs, airways, trachea, and nasal passages and sinuses. Tracheitis was evident in the intranasally infected group only. Lesions were generally necrotizing and hemorrhagic, neutrophilic, and increased in extent and severity in a time-dependent fashion. Viral intracytoplasmic inclusion bodies, immunolabeled viral antigen, or virions were readily seen in epithelial tissues, smooth muscle cells of airways and vessels, fibroblasts, periosteal cells, perineural cells, and macrophages. Although the extension of infection appeared to be primarily direct, lesions suggesting hematogenous dissemination were occasionally noted in bone marrow and skin. Transmission electron microscopy demonstrated features of cell injury or death, virion assembly and maturation, and both A-type and B-type inclusions.

CONCLUSIONS

Aerosol inoculation of BALB/c mice with cowpox virus provides a reliable and facilitative model of aerosol-transmitted, orthopoxviral respiratory disease.

TATA-Binding protein-TATA interaction is a key determinant of differential transcription of silkworm constitutive and silk gland-specific tRNA(Ala) genes

We have investigated the contribution of specific TATA-binding protein (TBP)-TATA interactions to the promoter activity of a constitutively expressed silkworm tRNA(C)(Ala) gene and have also asked whether the lack of similar interactions accounts for the low promoter activity of a silk gland-specific tRNA(SG)(Ala) gene. We compared TBP binding, TFIIIB-promoter complex stability (measured by heparin resistance), and in vitro transcriptional activity in a series of mutant tRNA(C)(Ala) promoters and found that specific TBP-TATA contacts are important for TFIIIB-promoter interaction and for transcriptional activity. Although the wild-type tRNA(C)(Ala) promoter contains two functional TBP binding sequences that overlap, the tRNA(SG)(Ala) promoter lacks any TBP binding site in the corresponding region. This feature appears to account for the inefficiency of the tRNA(SG)(Ala) promoter since provision of either of the wild-type TATA sequences derived from the tRNA(C)(Ala) promoter confers robust transcriptional activity. Transcriptional impairment of the wild-type tRNA(SG)(Ala) gene is not due to reduced incorporation of TBP into transcription complexes since both the tRNA(C)(Ala) and tRNA(SG)(Ala) promoters form transcription complexes that contain the same amount of TBP. Thus, the deleterious consequences of the lack of appropriate TBP-TATA contacts in the tRNA(SG)(Ala) promoter must come from failure to incorporate some other essential transcription factor(s) or to stabilize the complete complex in an active conformation.

cagA gene and vacA alleles in Spanish Helicobacter pylori clinical isolates from patients of different ages

The prevalence of the cagA gene and vacA alleles in 124 Spanish Helicobacter pylori clinical isolates from patients of different ages ranging from 3 to 78 years was studied (21 patients < or = 10 years, 30 patients 11-20 years, 17 patients 21-40 years, 31 patients 41-60 years and 25 patients 61-80 years). The cagA gene and vacA s1 or vacA s2 alleles were identified by PCR from the strain. 66.9% of the isolates were cagA+ and 33.1% cagA-. vacA s1 was detected in 48.4% of the isolates and vacA s2 in 51.6%. 44.4% of patients were cagA+/vacA s1, 22.5% were cagA+/vacA s2, 4% were cagA-/vacA s1 and 29% were cagA-/vacA s2. The percentage of cagA+ isolates and the vacA s1 alleles in the different groups were as follows: 23.8% and 28.6% in 0-10 years, 40% and 30% in 11-20 years, 88.2% and 70.6% in 21-40 years, 90.3% and 70.9% in 41-60 years and 92% and 44% in the 61-78 years group. 93% (54/58) of isolates found in ulcer patients and 90.9% (10/11) of isolates from gastritis patients older than 20 years were cagA+. In patients younger than 20 years ulcer disease was rare with 60% of isolates being cagA+ (3/5) compared with 31.6% cagA+ isolates (12/38) in patients suffering from gastritis in the younger group. The prevalence of the cagA gene and vacA s1 allele increased with age, being more frequent in older patients than in younger.

Complement resistance of capsulated strains of Aeromonas salmonicida

The complement resistance of Aeromonas salmonicida strains grown under conditions promoting capsule formation was investigated using well characterized strains and their isogenic mutants. Complement resistance was previously studied using the same strains growing under non-capsulating conditions. The serum resistant strains were found to activate complement, but rapidly degrade C3b preventing productive formation of the lytic complex C5b-9. Isogenic lipopolysaccharide rough mutants grown under non-capsulating conditions were serum sensitive, binding a large amount of C3b and leading to productive formation of C5b-9. When grown under conditions promoting capsule formation, these mutants were partially resistant to complement because less C3b is bound to them and also partially degraded, with a concomitant reduction in lytic C5b-9.

Role of adenine nucleotides in the activation of microsomal cholesterol ester hydrolase by fructose or adenosine in rat hepatocytes

In the present study we have analysed the potential relationship between the cellular level of adenine nucleotides and the activity of microsomal cholesterol ester hydrolase by treating rat hepatocyte suspensions with fructose or adenosine. Fructose raised the microsomal hydrolysis of cholesteryl esters as a function of the dose. This ketose led to marked decreases in the cell level of ADP, ATP and total adenine nucleotide whereas that of AMP increased slightly, thus giving a rise in the cellular AMP/ATP ratio. The effects remained virtually constant over a period of 60 min. Incubation of hepatocytes in a Ca(2+)-free medium with or without ethylene glycol-bis(beta-aminoethyl ether) N,N,N',N'-tetraacetic acid blocked by 40% the fructose-induced activation of cholesterol esterase whereas the rise in AMP/ATP was unaffected. Adenosine caused dose-dependent activations of cholesterol ester hydrolase and raised AMP, ADP and ATP concentrations as well as the AMP/ATP ratio. 2-Chloro-adenosine and N6-[L-2-phenyl-isopropyl] adenosine, non-metabolizable analogues of adenosine, did not mimic the effects of the nucleoside. A positive linear correlation exists between the percentage rises in the activity of microsomal cholesterol ester hydrolase and those in the intracellular AMP/ATP ratio in fructose- or adenosine-treated cells. These results indicate that, in microsomes from intact hepatocytes, the breakdown of cholesteryl esters to yield cholesterol and fatty acids is stimulated by fructose and adenosine and this can be explained in part by the increase in the cellular AMP/ATP ratio. In the case of fructose, also a Ca(2+)-dependent mechanism is involved.

Comparison of the effects of cyclic AMP analogues on cholesterol metabolism in cultured rat and hamster hepatocytes

The effects of two cell-permeable cyclic AMP analogues, 8-chloro cyclic AMP (8-Cl cAMP) and 8-(4-chlorophenylthio) cyclic AMP (8-CPT cAMP), on cholesterol esterification, cholesteryl ester hydrolysis and bile acid synthesis were compared in cultured rat and hamster hepatocytes. Cholesterol esterification, as measured by the incorporation of [3H]oleate into cholesteryl ester, was increased by 58-88% by the analogues in rat hepatocytes and by 33-43% in hamster cells. The response in rat hepatocytes, however, was observed after a relatively short incubation time (28% increase after 1 hr), whereas that in hamster cells required a longer period (36% after 12 hr) to become apparent. The activity of the cytosolic neutral cholesteryl ester hydrolase in rat hepatocytes was also stimulated by both cyclic AMP analogues (31-37%, but the microsomal activity was unaffected. In hamster hepatocytes, however, microsomal cholesteryl ester hydrolase activity was increased (47-80%) in the presence of 8-Cl cAMP or 8-CPT cAMP. Bile acid synthesis was increased by 8-CPT cyclic AMP in rat cells (approximately 25%) but was unchanged by both analogues in hamster hepatocytes. These results indicate significant differences in the way in which cholesterol metabolism responds to cyclic AMP in cultured rat and hamster hepatocytes.

Quantitative measurement of muscle strength in the mouse

We have designed a special dynamometer for measuring mouse forelimb muscle strength and endurance. The device exploits a mouse's tendency to grasp a horizontal metal bar while suspended by its tail. A threshold value for the magnitude and duration of force that the mouse can exert is obtained by first allowing the animal to grasp the bar and then applying a steadily increasing downward force to the opposite end of a cable to which the mouse attaches. The bar is attached to a force transducer and pen recorder to produce a permanent record of the force produced by the mouse. Test results show that this dynamometer provides quantitative measurements of muscle strength and endurance in the mouse. Comparisons between experimental groups of normal and wobbler mice, a model for lower motor neuron disease, show that both the force exerted by the animals (muscle strength), and the duration of the pull (endurance), can be quantified and statistically analyzed. This technique can be used as an assay for quantitating the effects of in vivo drug treatments on murine neuromuscular disorders.

Inhibition of microsomal cholesterol ester hydrolase by okadaic acid in isolated rat hepatocytes

Okadaic acid, a potent and specific inhibitor of protein phosphatases 1 (IC50 10-20 nM) and 2A (IC50 0.05-2 nM) caused early and sustained inhibitions of microsomal cholesterol ester hydrolase activity in hepatocyte suspensions. The changes in the kinetic properties of the esterase and its response to exogenous alkaline phosphatase and cyclic AMP-dependent protein kinase after cell exposure to 1 microM or 1 nM okadaic acid differed markedly among themselves, which suggests the involvement of both protein phosphatases 1 and 2A in the regulation of the microsomal hydrolysis of cholesterol esters. Furthermore, the inhibitory effect of okadaic acid is likely to be independent of the dibutyryl-cyclic AMP promoted cell events leading to stimulation of esterase activity.

Purification of a new galactanase from Penicillium oxalicum catalysing the hydrolysis of beta-(1----5)-galactofuran linkages

An endo beta-(1----5)-galactofuranase from Penicillium oxalicum has been purified 91-fold. The enzyme is a basic glycoprotein with a pI 7.9 and 20% (w/w) carbohydrate content, galactose being the principal sugar. The apparent Mr of the enzyme estimated by denaturing gel electrophoresis was 77,000. The optimum pH was 5.0, and the enzyme was stable over the pH range 4.0-7.5. This enzyme hydrolyses specifically (1----5)-linked beta-D-galactofuranose residues in homo- and heterogalactans, but did not hydrolyse o-nitrophenyl galactose and beta-(1----5)-galactofuranbiose. Km and Vmax. values were 1.2 mg.ml-1 and 0.55 mumol.h-1 respectively when Eupenicillium crustaceum beta-(1----5)-galactofuran was used as substrate. The enzyme showed high affinity for different separation gels and proteins. The enzyme specificity and its mode of action showed that it could be an useful tool for analysing the fine structure of polysaccharides.

Diurnal variations of rat liver enzymes catalyzing cholesterol ester hydrolysis

Cholesterol ester hydrolase activity was determined at 3 h time intervals over 24 h in lysosomes, cytosol and microsomes from ad libitum-fed and 24 h food-deprived female rat liver. Diurnal rhythms were identified for the acid and neutral esterases, which were strikingly changed by fasting. In fed animals, lysosomal esterase specific activity exhibited a peak at noon and a sustained medium rate at early darkness, whereas total esterase was maximal at midnight. The circadian patterns of the cytosolic and the microsomal esterases paralleled each other, though the amplitude of rhythms differed, showing higher activities around midnight. After fasting, cholesterol esterase activity from all cell fractions reached a maximum near dark onset. These results are the first to indicate that cholesteryl ester hydrolysis may play a role in generating the diurnal rhythm of hepatic cholesterol.

Neutral cholesteryl ester hydrolase in the rat lactating mammary gland: regulation by phosphorylation-dephosphorylation

The characteristics of neutral cholesteryl ester hydrolase activities found in the microsomal and cytosolic subcellular fractions of rat lactating mammary tissue were investigated. The enzymes were assayed using cholesteryl oleate dispersed as a mixed micelle with phosphatidylcholine and sodium taurocholate (molar ratio 1:4:2) as substrate. This method gave activities approx. 20-fold higher than those seen when cholesteryl oleate was added in ethanol. Addition of phosphatidylcholine and sodium taurocholate to the assays using the ethanol-dissolved substrate did not increase the activities observed. When the cholesteryl oleate was dispersed with phosphatidylcholine only (molar ratio, 1:4) the activity of the two neutral cholesteryl ester hydrolases was also decreased considerably compared to that found with mixed micelles. In this case, however, approx. 60% of the cytosolic, but only 10% of the microsomal activity, was restored by separate addition of sodium taurocholate. The activities of both the microsomal and the cytosolic neutral cholesteryl ester hydrolases were inhibited by MgCl2, and this inhibition was almost completely reversed by the addition of an equimolar concentration of ATP. At a fixed concentration of MgCl2 increasing concentrations of ATP increased the enzyme activities in a dose-dependent way. The activity of the microsomal, but not the cytosolic enzyme was enhanced by a cyclic AMP-dependent protein kinase and both activities were inhibited by alkaline phosphatase (bovine milk). These results provide evidence for the regulation of neutral cholesteryl ester hydrolases in the rat lactating mammary gland by mechanisms involving phosphorylation-dephosphorylation and therefore suggest that these enzymes may be under hormonal control.

Cholesterol ester cycle in rat liver: effects of estradiol and progesterone

The regulation of the enzymatic synthesis and hydrolysis of cholesteryl esters by female sex hormones has been investigated in rat liver. When the effects of estradiol and progesterone were studied in "in vitro" incubations of hepatic microsomes, a dual effect was observed. Progesterone inhibited both microsomal cholesterol ester hydrolase and acyl-CoA: cholesterol acyltransferase activities in a concentration-dependent manner; however, the presence of estradiol stimulated cholesterol ester hydrolysis while it inhibited cholesterol ester formation. The administration of pharmacological doses of estradiol for three consecutive days resulted in decreased cytosolic and microsomal cholesterol esterase activities followed by an increased microsomal cholesteryl esters content whereas acyl-CoA: cholesterol acyltransferase and other microsomal parameters remained unchanged. Examination of the effects of the short-term treatment with pharmacological doses of progesterone showed that treatment was less effective in changing the hepatic pattern of the cholesteryl esters cycle, since only cytosolic cholesterol ester hydrolase activity diminished slightly. Neither cytosolic nor microsomal cholesterol esterase or acyl-CoA: cholesterol acyltransferase were consistently affected by the administration of therapeutical doses of estradiol or progesterone for 21 days, although both the free cholesterol-phospholipid and the total cholesterol-phospholipid molar ratios decreased moderately. The effect of the hormonal vehicle, propylene glycol, on some microsomal lipid parameters is finally discussed.

Cephalosporin C acylase in the autolysis of filamentous fungi

Cephalosporin C acylase activity was studied using fluorescamine determination of free--NH2 groups produced in the deacylation of cephalosporin C by the enzyme. Fourteen fungi from different genera were studied and low extracellular cephalosporin C acylase activity was found in the genera Aspergillus, Fusarium and Penicillium. Forty one fungi of these genera were checked but not all presented acylase activity. The enzyme was generally found to be an extracellular enzyme and during the process of autolysis its activity increased with incubation time and with increasing pH of the medium. In no case was beta-lactamase activity detected. Penicillium rugulosum and Penicillium griseofulvum were identified as good cephalosporin C acylase producers. Deacetyl esterase activity was also detected in these fungi.

Endochitinase from Aspergillus nidulans implicated in the autolysis of its cell wall

An endochitinase from centrifuged autolyzed cultures of Aspergillus nidulans has been purified 100 times. The enzyme has Mw 27,000, pI of 4.8 units, pH optimum around 5 pH units. It is unstable at temperature greater than 70 degrees C and does not have a cation requirement. It is inhibited by Hg2+, Cu2+, Ca2+ and Ag+ and it does not have muramidase activity. The enzyme depolymerizes chitin rapidly with production of high molecular weight polysaccharides, and then slowly degrades these with production of N,N'-diacetylchitobiose. The enzyme hydrolyzes N,N',N''-triacetylchitotriose with production of N,N'-diacetylchitobiose and N-acetylglucosamine and this hydrolysis is inhibited by other chitin oligomers and N-acetylglucosamine. This enzyme hydrolyzes in the same way the chitin obtained from the cell wall of Aspergillus nidulans.

Determination of cephalosporin-C amidohydrolase activity with fluorescamine

A spectrophotometric procedure for the assay of cephalosporin-C amidohydrolase activity, based on the determination of the 7-aminocephalosporanic acid (7-ACA) produced in the hydrolysis of cephalosporin-C by the enzyme, is described. This procedure can be used to detect 7-ACA over a range of 10 to 200 micrograms mL-1. The same method can be used as a fluorometric procedures with a 100-fold greater sensitivity. At pH 4.5 7-ACA produces a strong fluorophor with fluorescamine, detectable spectrophotometrically at 378 nm and fluorometrically at an excitation of 378 nm and emission of 495 nm. At this pH the fluorophors formed with cephalosporin-C, proteins and aminoadipic acid present minimal absorbance values. The conditions for maximal detection of 7-ACA in the presence of proteins, cephalosporin-C and aminoadipic acid have been determined.