TiO2nanotubes enriched with calcium, phosphorous and zinc: promising bio-selective functional surfaces for osseointegrated titanium implants

TiO₂nanotubes enriched with Ca, P, and Zn by reverse polarization anodization, are promising bio-selective functional structures for osseointegrated titanium implants.

The Dependence of Crops for Pollinators and the Economic Value of Pollination in Brazil

Food production is challenged by changes in climate and land use and expanding human population growth. Proper pollination can increase the production and quality of fruit, nut, oil, and fiber crops. We reviewed crop dependence on pollinators and estimated the economic value of pollination per year for each crop in Brazil. We analyzed 141 crops and found that 85 depend on pollinators. Almost one-third of these crops have an essential or great dependence on pollinators. The economic contribution of pollinators totals ∼30% (∼US$12 billion) of the total annual agricultural income of the dependent crops (totalizing almost US$45 billion). However, half of these figures includes soybean crop (US$5.7 billion of pollinators' contribution and US$22 billion of annual income). Soybean was considered as having a modest dependence on pollinators, but this remains controversial because pollinator dependence might vary among different varieties cultivated in Brazil. Moreover, we have no information about pollinator dependence regarding some important crops, showing the urgent need for basic research into reproductive biology and pollination ecology.

Overexpression and purification of PWL2D, a mutant of the effector protein PWL2 from Magnaporthe grisea

The rice blast disease caused by the ascomycete Magnaporthe grisea continues to cause a tremendous impact in rice (Oryza sativa) cultures around the world. Elucidating the molecular basis of the fungus interactions with its host might help increase the general understanding of the pathogen-host relationship. At the moment of invasion, the fungus secretes effectors that modify host defenses and cellular processes as they successively invade living rice cells. PWL2, an effector protein, is a known AVR (avirulence) gene product. The PWL2 gene prevents the fungus from infecting weeping lovegrass (Eragrostis curvula). In this study, we identified a PWL2 allele gene (which we termed PWL2D) in a strain of M. grisea. The sequence of PWL2D has only two bases different from that of PWL2, producing alterations in residue 90 and residue 142. However, the alteration of residue 90 (from D(90) to N(90)) is critical to gene function. Here, we cloned the gene PWL2D in a pET System vector, expressed the gene product in Escherichia coli and evaluated by spectroscopic techniques some aspects of the PWL2D structure. While TRX-tagged PWL2D is prone to aggregation, the solubility of PWL2D is improved when it is overexpressed without its original signal peptide. Expression and purification procedures for these constructs are described. Finally, we found out that the protein seems to be an intrinsically disordered protein. Results from these studies will facilitate structural analysis of PWL2D and might contribute to understanding the gene's function and of fungal/plant interactions.

Redescription of Rhabdochona anguillae (Nematoda: Rhabdochonidae), a parasite of eel, Anguilla anguilla, in Europe

The nematode Rhabdochona anguillae Spaul, 1927, a specific intestinal parasite of the European eel, Anguilla anguilla (L.), is redescribed and illustrated from specimens collected from eels of the Sousa River, northern Portugal (prevalence 20%, intensity 2-13). The species is characterized by the presence of 14 anterior teeth in the prostom, small non-bifurcate deirids, absence of lateral preanal papillae, by the length (0.460-0.660 and 0.130-0.150 mm) and the shape of spicules, fairly large (0.041-0.054 x 0.025-0.030 mm) mature eggs without filaments, and by the bluntly pointed to rounded tip of the tail. Its morphological features are discussed in relation to other congeneric species. This nematode has hitherto been recorded only from eels in southern Europe (Portugal, Spain, Bulgaria).

Lichen planus and chronic hepatitis C: exacerbation of the lichen under interferon-alpha-2a therapy

A 51-year-old man was treated for histologically proven chronic hepatitis C with 3 MU of recombinant interferon-alpha-2a three times a week. Before interferon therapy, a mild lichen planus (hypertrophic variant) had been diagnosed, which exacerbated within 6 weeks of treatment to a severe erosive oral form. Then interferon therapy was stopped because local measures did not improve oral lesions. However, the patient tolerated interferon therapy well, and the initially four-fold elevated aminotransferase levels returned to normal. Nine weeks after discontinuation of interferon therapy, nearly all the buccal mucous membrane lesions had disappeared. But 8 weeks after withdrawal of interferon, aminotransferase levels rose again to six times the normal range. Treating physicians should know that a pre-existing lichen planus would potentially exacerbate, as a side effect of interferon-alpha-2a therapy of chronic hepatitis. However, further observations are needed to decide its clinical relevance.

[The endocrine pancreas]

The islets of Langerhans provide energy storage and disposal, and protection from plasma glucose excursions, especially hypoglycemia. Insulin-dependent diabetes mellitus (IDDM) results from autoimmune beta-cell damage. Prevention of IDDM has already been achieved in animal investigation and some centers are now screening and treating individuals at high risk for developing IDDM. Immunosuppressive drugs can induce transient remission of recent-onset IDDM. Intensive insulin treatment of IDDM delays the onset and slows the progression of long-term complications. Non-insulin dependent diabetes mellitus (NIDDM) is the result of beta-cell malfunction and is strongly associated with X syndrome. Diet and exercise are of undoubted importance in NIDDM prevention and treatment. Functional endocrine tumors of the pancreas (FET) are rare hormone and peptide-secreting neoplasms. These peptides may or may not occur naturally in the islets. FETs often occur with multiple endocrine neoplasia 1 (MEN 1) so that MEN-1 screening should always be performed, and extended to family members whenever diagnosed. Drugs--alcohol, insulin and sulfonilureas--are the main cause of hypoglycemia. Insulinoma is the main cause of post-absorptive organic hypoglycemia. Non islet-cell tumors seldom cause hypoglycemia. Insulinoma often is a solitary tumor, but it may be multicentric and may coexist with cell hyperplasia and nesidioblastosis. Symptoms of neuroglycopenia may be mistaken for neuropsychiatric disease. The diagnosis is based on confirmation of post absorptive hypoglycemia and hyperinsulinism. Gastrinoma causes Zollinger-Ellison syndrome (ZES) which is characterized by fulminating peptic ulcer disease. The tumor is often malignant, and it may be multicentric and may occur with cell hyperplasia and nesidioblastosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Anal tonometry: a quick method of anal manometry

Evaluation of anal sphincter tonic activity is important in the proctologic clinic. However, manometric techniques are expensive, complex, and only available in some centers. Because there is often an in-office need for having objective measurements of anal tonic activity, in our clinic we introduced a simple method for measurement of anal pressures. This method is based on the flow of air in an open circuit by using a rubber probe with a side opening at one end. Pressure is assessed by an ordinary manometric gauge for arterial pressure. With this simple instrument, the following parameters are measured: 1) anal resting pressure, 2) squeeze pressure, 3) functional length of the anal canal, and 4) descent of the perineum on staining. After testing the technique in 100 healthy persons, it was applied to 130 patients with several proctologic disorders. Differences in pressures were found between controls and patients with anal fissure (high resting pressures), and patients with anal incontinence (low resting and/or squeeze pressures). A correlation was also found between the descending perineum measured by this method and by defecography. This simple instrument is useful in the office as the first approach to the function of the anal sphincters and the pelvic floor. Nowadays, so-called anal tonometry is part of the proctologic examination in our department, because it is simple, reliable, and takes only a few minutes.

[Biguanides in the treatment of diabetes mellitus]

Biguanides are useful drugs in diabetes but their indications are very precise. The danger of lactic acidosis can be avoided with the use of metformin, the less toxic of biguanides, and strict respect for contraindications. All biguanides have a similar action, through different pharmacokinetics, and besides their hypoglycemic effect, have a favourable action on blood lipids, which increases their usefulness. Haemorheological effects, recently studied in animal research, may open a new field in the employment of biguanides.