Toxicity of ochratoxin A in aBrevibacillus brevis — Growth inhibition assay

Ochratoxin A (OTA) is a nephrotoxic, carcinogenic and immunosuppressive mycotoxin. It can be detoxified by various microorganisms, e.g. different yeast strains, via metabolisation into ochratoxin α (OTα). Within this study a growth inhibition assay was developed to compare the toxicity of OTA and its degradation product OTα. As an indicator organismBrevibacillus brevis was used. The assay was performed in microtiterplates. Growth inhibition was determined by comparing the optical density values ofBrevibacillus brevis cultures grown in medium supplemented with OTA/OTα and OTA/OTα-free medium, respectively. It could be shown thatB. brevis is sensitive to OTA (EC₁₀₀=0.5 mg/L±0.03 mg/L), which is not the case for its metabolite OTα. Therefore this bioassay is a useful tool to show the detoxification of OTA to OTα by microbial degradation. Presented at the 25^th Mykotoxin Workshop in Giessen, Germany, May 19–21, 2003     

Assessment of Heavy Metals Pollution in Sediments of the Korbevačka River in Southeastern Serbia

The Korbeva?ka River is located in the southeastern part of Serbia. This river is a main recipient of all kinds of pollutants from the Pb?Zn mine “Grot.” Sediments from the Korbeva?ka River were studied to determine the distribution of the metals along the river, assess the quality of sediment, and find the degree of contamination. The concentration of iron, manganese, nickel, copper, zinc, cadmium, lead, mercury, arsenic, chromium, and barium were determined. River sediments were collected and analyzed for heavy metal concentration using atomic absorption spectrophotometer. The degree of pollution in the sediments of the Korbeva?ka River has been evaluated based on Canadian sediment quality guidelines, enrichment factor (EF), geo-accumulation index (I_geo) and pollution load index (PLI). Inter-metal associations have been evaluated by Pearson correlation coefficients (r). The results indicated that: (1) sediments have been polluted with Pb, Cd, Zn, and Cu and have high anthropogenic influences; (2) the calculation of geo-accumulation index suggests that the Korbeva?ka River sediments have background concentrations of Fe, Cr, and Ni (I_geo < 1); (3) the co-precipitation (inclusion, occlusion, and adsorption) of heavy metals (except As and Ba) with Mn and Fe geochemical phases.     

Assessing Risks of Heavy Metal Toxicity in Agricultural Soils: Do Microbes Matter?

Deleterious effects of heavy metals on soil microorganisms are reviewed in relation to the complexities involved in their study. There is strong evidence that soil microbes are more sensitive to heavy metals than animals or crop plants. Decisions concerning limits considered to be ‘safe’ in terms of protection of soil microorganisms or soil microbial processes from metal toxicity depend on the organisms considered and value judgements as to their importance. At present there is a large discrepancy in actual concentrations of heavy metals that are allowed to accumulate in agricultural soils between different countries. The approach of attempting to achieve zero accumulation of heavy metals in soils is undoubtedly the most conservative, but will severely restrict the recycling of sewage sludges to agricultural land.     

Control of Visceral Leishmaniasis in Latin America—A Systematic Review

Background

While three countries in South Asia decided to eliminate anthroponotic visceral leishmaniasis (VL) by 2015, its control in other regions seems fraught with difficulties. Is there a scope for more effective VL control in the Americas where transmission is zoonotic? We reviewed the evidence on VL control strategies in Latin America—diagnosis, treatment, veterinary interventions, vector control—with respect to entomological and clinical outcomes.

Methodology/Principal Findings

We searched the electronic databases of MEDLINE, LILACS, and the Cochrane Central Register of Controlled Trials, from 1960 to November 2008 and references of selected articles. Intervention trials as well as observational studies that evaluated control strategies of VL in the Americas were included. While the use of rapid diagnostic tests for VL diagnosis seems well established, there is a striking lack of evidence from clinical trials for drug therapy and few well designed intervention studies for control of vectors or canine reservoirs.

Conclusion

Elimination of zoonotic VL in the Americas does not seem a realistic goal at this point given the lack of political commitment, gaps in scientific knowledge, and the weakness of case management and surveillance systems. Research priorities and current strategies should be reviewed with the aim of achieving better VL control.     

Aβ Toxicity in Alzheimer's Disease

Alzheimer's Disease (AD), the most common age-related neurodegenerative disorder, is characterized by progressive cognitive decline, synaptic loss, the formation of extracellular β-amyloid plaques and intracellular neurofibrillary tangles, and neuronal cell death. Despite the massive neuronal loss in the ‘late stage’ of disease, dendritic spine loss represents the best pathological correlate to the cognitive impairment in AD patients. The ‘amyloid hypothesis’ of AD recognizes the Aβ peptide as the principal player in the pathological process. Many lines of evidence point out to the neurotoxicity of Aβ, highlighting the correlation between soluble Aβ oligomer accumulation, rather than insoluble Aβ fibrils and disease progression. Pathological increase of Aβ in AD brains, resulting from an imbalance between its production, aggregation and clearance, might target mitochondrial function promoting a progressive synaptic impairment. The knowledge of the exact mechanisms by which Aβ peptide impairs neuronal function will help us to design new pharmacological tools for preventing AD neurodegeneration.     

Histoplasmosis—A Review of Three Cases Studied in San Diego County

Three cases of histoplasmosis, a disease seldom reported in California, were diagnosed clinically by the authors in San Diego County. It is probable that there is a higher incidence of this disease in California than is at present recognized.Travel history, histoplasmin skin testing and serologic studies for mycotic infection are important in the diagnosis. Cultures of secretions and biopsy material are of great value if positive; but negative cultures (at least in non-endemic areas) do not rule out the disease. Travel and migration to and from endemic areas present opportunities for this disease to constitute a diagnostic problem far from the geographic area in which the disease was acquired.Although usually benign, histoplasmosis may be severe in the acute state, may disseminate or may be chronically active and progressive. Amphotericin B is the only effective chemotherapeutic agent and it is usually reserved for these forms of the disease.     

The Role of Globo-Series Glycolipids in Neuronal Cell Differentiation—A Review

Alterations in glycolipid composition as well as glycosyltransferase activities during cellular differentiation and growth have been well documented. However, the underlying mechanisms for the regulation of glycolipid expression remain obscure. One of the major obstacles has been the lack of a well defined model system for studying these phenomena. We have chosen PC 12 pheochrom-ocytoma cells as a model because (a) the properties of these cells have been well characterized, and (b) they respond to nerve growth factor (NGF) by differentiating into sympathetic-like neurons and are amenable to well-controlled experimentation. Thus, PC12 cells represent a suitable model for studying changes in glycolipid metabolism in relation to cellular differentiation. We have previously shown that subcloned PC12 cells accumulate a unique series of globo-series neutral glycolipids which are not expressed in parental PC12 cells. This unusual change in glycolipid distribution is accompanied by changes in the activities of specific glycosyltransferases involved in their synthesis and is correlated with neuritogenesis and/or cellular differentiation in this cell line. We have further demonstrated that changes in the glycosyltransferase activities may be modulated by the phosphorylation states of the cells via protein kinase systems. We conclude that these unique globo-series glycolipids may play a functional role in the initiation and/or maintenance of neurite outgrowth in PC12 cells.     

Hormetic Effects of Heavy Metals in Aquatic Snails: Is a Little Bit of Pollution Good?

Hormesis is the term to describe a stimulatory effects associated with a low dose of a potentially toxic substance or stress. We had anecdotal evidence of hormetic effects in some of our previous experiments concerning the influence of heavy metals on aquatic snail growth and recruitment. We therefore repeated a version of an earlier experiment but this time we expanded our low-dose treatments and increased our sample size. We also explored if metals had a hormetic effect on algae periphyton. We raised snails in outdoor mini-ecosystems containing lead, zinc, and cadmium-contaminated soil from an Environmental Protection Agency Superfund site in the Silver Valley of northern Idaho. The snails came from two sites. One population (Physella columbiana) has evolved for 120 years in the presence of heavy metals and one (Lymnaea palustris) has not. We found that P. columbiana exhibited hormesis with snails exposed to small amounts of metals exhibiting more reproduction and growth than snails not exposed to metals. Naturally occurring Oscillatoria algae also exhibited a hormetic effect of heavy metals but L. palustris did not display hormesis. Large doses negatively impacted all three species. Overall the levels of cadmium, lead, and zinc measured in the tissues of the snails were inversely correlated to the number of snails recruited into the tub populations. Only in comparisons of the lowest metal treatment to the control treatment is a positive effect detected. Indirect effects on competing species of snails, periphyton, and also fishermen, may be less favorable.     

Space Medicine—A Review of Current Concepts

Space medicine deals with the branch of research involved with the adaptation of humans to the unique environment of space. More than 100 people have traveled in space. The day will come when some human beings will spend all their time in space. Medical problems encountered in space, such as motion sickness, negative nitrogen and calcium balance, anemia and radiation exposure, are issues that already affect medical practice outside aerospace medicine.     

TRANSURETHRAL PROSTATECTOMIES—A Review of 560 Cases

Of 560 prostatectomies in an 11-year period on patients with benign or malignant disease of the prostate gland, almost 98 per cent were done transurethrally.Although many of the patients were considered to be in poor condition preoperatively, results achieved by the transurethral operation were excellent or good in 91 per cent of those who had benign disease of the prostate and in 84 per cent of those with malignant invasion. The rate of deaths attributable to the operation was 3.1 per cent in the group of patients with benign disease, 5.3 per cent in patients who had cancer.Complications, such as urinary incontinence, persistent pyuria, epididymitis, strictures of the urethra and of the meatus, and contracture of the neck of the bladder, arose in a surprising number of cases.     

MULTIPLE MYELOMA—A Review of 26 Cases

Multiple myeloma is a rare, malignant disease of bone marrow which affects principally the vertebrae, ribs, pelvis and skull but may involve any part of the skeleton. Severe demineralization and destructive lesions of bones, producing severe pain and debility, are distinctive features. The disease is further distinguished by abnormalities of blood proteins and in some cases by the excretion in the urine of Bence-Jones protein, which seldom, if ever, is found in association with any other disease.X-ray examination is frequently helpful. In 22 of 24 cases (of a series of 26 cases) in which films were available, definite abnormalities were noted. Spontaneous fractures, particularly of vertebrae, are common.The diagnosis of the disease rests on the identification of the myeloma cell. This is best accomplished by aspiration of bone marrow. In several of the 26 cases in the series diagnosis was made by a neurosurgeon at the time of operation to relieve pressure on the spinal cord. The myeloma cell has a very characteristic appearance.In the present series the average duration of life after the onset of symptoms was only nine months. One patient, however, survived for at least ten years.     

ENDOMETRIOSIS—A Review

Endometriosis, the cause of which is unknown, is on the increase. Treatment is surgical—conservative in the childbearing years. Hormonal therapy is sometimes palliative for a time, and the disease may regress during pregnancy. Endometriosis of the bowel should be borne in mind in the differential diagnosis of partial obstruction.The literature contains reports of 14 cases of ovarian carcinoma arising from endometriosis.     

Measurement of Physician-Patient Communication—A Systematic Review

Background

Effective communication with health care providers has been found as relevant for physical and psychological health outcomes as well as the patients'' adherence. However, the validity of the findings depends on the quality of the applied measures. This study aimed to provide an overview of measures of physician-patient communication and to evaluate the methodological quality of psychometric studies and the quality of psychometric properties of the identified measures.

Methods

A systematic review was performed to identify psychometrically tested instruments which measure physician-patient communication. The search strategy included three databases (EMBASE, PsycINFO, PubMed), reference and citation tracking and personal knowledge. Studies that report the psychometric properties of physician-patient communication measures were included. Two independent raters assessed the methodological quality of the selected studies with the COSMIN (COnsensus based Standards for the selection of health status Measurement INtruments) checklist. The quality of psychometric properties was evaluated with the quality criteria of Terwee and colleagues.

Results

Data of 25 studies on 20 measures of physician-patient communication were extracted, mainly from primary care samples in Europe and the USA. Included studies reported a median of 3 out of the nine COSMIN criteria. Scores for internal consistency and content validity were mainly fair or poor. Reliability and structural validity were rated mainly of fair quality. Hypothesis testing scored mostly poor. The quality of psychometric properties of measures evaluated with Terwee et al.''s criteria was rated mainly intermediate or positive.

Discussion

This systematic review identified a number of measures of physician-patient communication. However, further psychometric evaluation of the measures is strongly recommended. The application of quality criteria like the COSMIN checklist could improve the methodological quality of psychometric property studies as well as the comparability of the studies'' results.     

Can Cone Scales and Bark of Aleppo Pine Be Used in the Biomonitoring of Some Heavy Metals?

The highest levels of Pb in soils and needles were detected in the Lisbon Botanical Garden, reflecting the intense car circulation since the end of the late nineteenth century, and the presence of tetraethyl lead in petrol. Levels of Pb in Aleppo bark were at or above the threshold values for plant tissues as defined by the UN-ECE/EC (>4–30 μg/g). Nickel was easily washed by distilled water from the bark, indicating a predominant adsorption due to atmospheric deposition, while only Pb was water-extracted from cone scales, but no more than 0.88 μg/g (4.3% of the total). If we take into account the dry weight of each cone, we can assess the amount of extractable lead present in a given time (ranges between 3.0 and 15.5 μg), although its eventual transfer to the ground through rainfall will be hampered by the cone architecture. The average levels of total Pb in the cones (12.7–35.4 μg/g) fall within the range defined by the UN-ECE/EC, generally; only the reference value is below 4 μg/g. Due to the high capabilities of allocating Pb inside the structure and through adsorption, Aleppo bark and cones can be very interesting tools in the monitoring of Pb.     

Pneumococcal Carriage in Sub-Saharan Africa—A Systematic Review

Background

Pneumococcal epidemiology varies geographically and few data are available from the African continent. We assess pneumococcal carriage from studies conducted in sub-Saharan Africa (sSA) before and after the pneumococcal conjugate vaccine (PCV) era.

Methods

A search for pneumococcal carriage studies published before 2012 was conducted to describe carriage in sSA. The review also describes pneumococcal serotypes and assesses the impact of vaccination on carriage in this region.

Results

Fifty-seven studies were included in this review with the majority (40.3%) from South Africa. There was considerable variability in the prevalence of carriage between studies (I-squared statistic = 99%). Carriage was higher in children and decreased with increasing age, 63.2% (95% CI: 55.6–70.8) in children less than 5 years, 42.6% (95% CI: 29.9–55.4) in children 5–15 years and 28.0% (95% CI: 19.0–37.0) in adults older than 15 years. There was no difference in the prevalence of carriage between males and females in 9/11 studies. Serotypes 19F, 6B, 6A, 14 and 23F were the five most common isolates. A meta-analysis of four randomized trials of PCV vaccination in children aged 9–24 months showed that carriage of vaccine type (VT) serotypes decreased with PCV vaccination; however, overall carriage remained the same because of a concomitant increase in non-vaccine type (NVT) serotypes.

Conclusion

Pneumococcal carriage is generally high in the African continent, particularly in young children. The five most common serotypes in sSA are among the top seven serotypes that cause invasive pneumococcal disease in children globally. These serotypes are covered by the two PCVs recommended for routine childhood immunization by the WHO. The distribution of serotypes found in the nasopharynx is altered by PCV vaccination.     

Studies of Mycorrhizal Fungi of Chinese Orchids and Their Role in Orchid Conservation in China—A Review

China has over 1,200 species of native orchids in nearly 173 genera. About one fourth of native species are of horticultural merit. Some species are of Chinese medicinal value. In fact, the demand on orchid species with high Chinese medicinal values such as Gastrodia elata, Dendrobium offcinale, along with demands on species of cultural importance, such as those in the genus of Cymbidium, is a major factor causing wild populations to diminish and in some cases, drive wild populations to the brink of extinction. These market demands have also driven studies on the role of mycorrhizal fungi in orchid seed germination, seedling and adult growth, and reproduction. Most of these mycorrhizal studies of Chinese orchids, however, are published in Chinese, some in medical journals, and thus overlooked by the mainstream orchid mycorrhizal publications. Yet some of these studies contained interesting discoveries on the nature of the mycorrhizal relationships between orchids and fungi. We present a review of some of these neglected publications. The most important discovery comes from the mycorrhizal studies on G. elata, in which the researchers concluded that those fungi species required to stimulate seed germination are different from those that facilitate the growth of G. elata beyond seedling stages. In addition, presence of the mycorrhizal fungi associated with vegetative growth of post-seedling G. elata hindered the germination of seeds. These phenomena were unreported prior to these studies. Furthermore, orchid mycorrhizal studies in China differ from the mainstream orchid studies in that many epiphytic species (in the genus of Dendrobium, as medicinal herbs) were investigated as well as terrestrial orchids (mostly in the genus Cymbidium, as traditional horticultural species). The different responses between epiphytic and terrestrial orchid seeds to fungi derived from roots suggest that epiphytic orchids may have a more general mycorrhizal relationship with fungi than do terrestrial orchid species during the seed germination stage. To date, orchid mycorrhizal research in China has had a strongly commercial purpose. We suggest that this continuing research on orchid mycorrhizal relationships are a solid foundation for further research that includes more rare and endangered taxa, and more in-situ studies to assist conservation and restoration of the endangered orchids. Knowledge on the identities and roles of mycorrhizal fungi of orchids holds one of the keys to successful restoration and sustainable use of Chinese orchids.     

THERAPEUTIC DONOR INSEMINATION—A Review of 440 Cases

Of 399 patients inseminated therapeutically with the semen of a donor, 303 became pregnant, the great majority of them within six months of the time inseminations were begun. The average number of inseminations was 6.2 and the average number of menstrual cycles over which they were carried out was 3.55. The greatest number of pregnancies occurred between the twelfth and the fifteenth day of the menstrual cycle.Seven patients had four pregnancies by this method, 17 had three and 59 had two.Emotional problems related to children of artificial insemination were far fewer than those associated with adoption.     

THE IMPAIRED DRIVER—A Review of the Facts

Traffic accidents have been subject to relatively little scientific study in California. A substantial barrier to adequate basic research in this field has been the assumption that more is known about the underlying causes of accidents than actually is. For example, within the medical profession, there is a tendency to assume that physical impairments of drivers are important in the causation of accidents, although little evidence has been collected to confirm or deny this assumption.Research into the underlying causes of accidents is a worthy but infinitely complex task. It must be accomplished before the driver''s contribution to accidents can be seen in proper perspective, its components identified and dealt with on a rational basis.