Casein kinase 2 phosphorylates and induces the SALL2 tumor suppressor degradation in colon cancer cells

Spalt-like proteins are Zinc finger transcription factors from Caenorhabditis elegans to vertebrates, with critical roles in development. In vertebrates, four paralogues have been identified (SALL1-4), and SALL2 is the family's most dissimilar member. SALL2 is required during brain and eye development. It is downregulated in cancer and acts as a tumor suppressor, promoting cell cycle arrest and cell death. Despite its critical functions, information about SALL2 regulation is scarce. Public data indicate that SALL2 is ubiquitinated and phosphorylated in several residues along the protein, but the mechanisms, biological consequences, and enzymes responsible for these modifications remain unknown. Bioinformatic analyses identified several putative phosphorylation sites for Casein Kinase II (CK2) located within a highly conserved C-terminal PEST degradation motif of SALL2. CK2 is a serine/threonine kinase that promotes cell proliferation and survival and is often hyperactivated in cancer. We demonstrated that CK2 phosphorylates SALL2 residues S763, T778, S802, and S806 and promotes SALL2 degradation by the proteasome. Accordingly, pharmacological inhibition of CK2 with Silmitasertib (CX-4945) restored endogenous SALL2 protein levels in SALL2-deficient breast MDA-MB-231, lung H1299, and colon SW480 cancer cells. Silmitasertib induced a methuosis-like phenotype and cell death in SW480 cells. However, the phenotype was significantly attenuated in CRISPr/Cas9-mediated SALL2 knockout SW480 cells. Similarly, Sall2-deficient tumor organoids were more resistant to Silmitasertib-induced cell death, confirming that SALL2 sensitizes cancer cells to CK2 inhibition. We identified a novel CK2-dependent mechanism for SALL2 regulation and provided new insights into the interplay between these two proteins and their role in cell survival and proliferation.

The Ancestry of Eastern Paraguay: A Typical South American Profile with a Unique Pattern of Admixture

Immigrants from diverse origins have arrived in Paraguay and produced important demographic changes in a territory initially inhabited by indigenous Guarani. Few studies have been performed to estimate the proportion of Native ancestry that is still preserved in Paraguay and the role of females and males in admixture processes. Therefore, 548 individuals from eastern Paraguay were genotyped for three marker sets: mtDNA, Y-SNPs and autosomal AIM-InDels. A genetic homogeneity was found between departments for each set of markers, supported by the demographic data collected, which showed that only 43% of the individuals have the same birthplace as their parents. The results show a sex-biased intermarriage, with higher maternal than paternal Native American ancestry. Within the native mtDNA lineages in Paraguay (87.2% of the total), most haplogroups have a broad distribution across the subcontinent, and only few are concentrated around the Paraná River basin. The frequency distribution of the European paternal lineages in Paraguay (92.2% of the total) showed a major contribution from the Iberian region. In addition to the remaining legacy of the colonial period, the joint analysis of the different types of markers included in this study revealed the impact of post-war migrations on the current genetic background of Paraguay.

Mating-based regulation and ligand binding of an odorant-binding protein support the inverse sexual communication of the greater wax moth, Galleria mellonella (Lepidoptera: Pyralidae)

In moths, sex pheromones play a key role in mate finding. These chemicals are transported in the antennae by odorant-binding proteins (OBPs). Commonly, males encounter conspecific females; therefore, several OBPs are male-biased. Less is known, however, about how the olfactory system of moths has evolved toward inverse sexual communication, ie where females seek males. Therefore, the objective of this study was to identify the profile of OBPs and their expression patterns in the bee hive pest, Galleria mellonella, a moth that uses inverse sexual communication. Here, OBP-related transcripts were identified by an RNA Sequencing (RNA-Seq) approach and analysed through both Reverse Transcription Polymerase Chain Reaction (RT-PCR) in different tissues and quantitative real-time PCR for two states, virgin and postmating. Our results indicate that G. mellonella has 20 OBPs distributed amongst different tissues. Interestingly, 17 of the 20 OBPs were significantly down-regulated after mating in females, whereas only OBP7 was up-regulated. By contrast, 18 OBP transcripts were up-regulated in males after mating. Additionally, binding assays and structural simulations showed general odorant-binding protein 2 (GOBP2) was able to bind sex pheromone components and analogues. These findings suggest a possible role of OBPs, especially GOBPs, in the inverse sexual communication of G. mellonella, with gene expression regulated as a response to mating.

Antennal Morphology and Localization of a Pheromone-Binding Protein of Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae)

In the sensory system of insects, olfactory sensilla constitute important functional elements for discriminating odors. Therefore, we used light microscopy and scanning electron microscopy to investigate the morphology and distribution of sensilla in the antennae of Lobesia botrana (Denis & Schiffermüller). In addition, we studied the expression of the gene encoding for pheromone-binding protein 1 (LbotPBP1) by in situ hybridization. Lobesia botrana antennae are filiform and are subdivided into three segments: scape, pedicel, and flagellum. The number of flagellum and their overall length were significantly higher and longer in males than in females. Six morphological types of sensilla (trichodea, chaetica, coeloconica, auricillica, basiconica, and styloconica) were identified on the antennae of both sexes. Trichodea sensilla were the most abundant on the antennae of L. botrana, and three subtypes, discerned by their lengths, were observed. However, sensilla trichodea subtype III was only present in male antennae. Moreover, LbotPBP1 expression was restricted to this type of sensilla, thus confirming its olfactory role, specifically under the context of sexual pheromone perception.

Repellent Effect and Metabolite Volatile Profile of the Essential Oil of Achillea millefolium Against Aegorhinus nodipennis (Hope) (Coleoptera: Curculionidae)

Aegorhinus nodipennis (Hope) (Coleoptera: Curculionidae) is an important native pest in fruit crops that is mainly found in European hazelnut fields in the south of Chile. We investigated the behavioral response of A. nodipennis to volatile compounds released from the essential oil of Achillea millefolium and its main constituent using olfactometric bioassays. Gas chromatographic and mass spectral analysis of the A. millefolium essential oil revealed the presence of 11 compounds. Monoterpene β-thujone (96.2%) was the main component of the oil. Other compounds identified were α-thujone, 1,8-cineole, p-cymene, and 4-terpineol, all with percentages below 1%. Both A. millefolium essential oil and thujone exhibited a repellent activity against this insect at the higher doses tested (285.7 ng/cm(2)), demonstrating their potential as repellents for this species.

The combination of axitinib followed by paclitaxel/carboplatin yields extended survival in advanced BRAF wild-type melanoma: results of a clinical/correlative prospective phase II clinical trial

BACKGROUND

Simultaneous chemotherapy with vascular endothelial growth factor (VEGF) inhibition has not shown additional benefit over chemotherapy alone in advanced melanoma. We tested administration of the potent VEGF inhibitor axitinib followed by paclitaxel/carboplatin to determine whether enhanced tumour proliferation during axitinib withdrawal leads to sustained chemosensitivity.

METHODS

We conducted a prospective phase II trial in metastatic melanoma patients with ECOG performance status 0-1 and normal organ function. Axitinib 5 mg PO b.i.d. was taken on days 1-14 of each 21-day treatment cycle, and carboplatin (AUC=5) with paclitaxel (175 mg m(-2)) was administered on day 1 starting with cycle 2. 3'-Deoxy-3'-(18)F-fluorothymidine ((18)F-FLT)-PET scans were performed in five patients to assess tumour proliferation on days 1, 14, 17, and 20 of cycle 1. Molecular profiling for BRAF was performed for all patients with cutaneous, acral, or mucosal melanoma.

RESULTS

The treatment was well tolerated. The most common grade 3 AEs were hypertension, neutropenia, and anaemia. Grade 4 non-haematologic AEs were not observed. Four of five patients completing (18)F-FLT-PET scans showed increases (23-92%) in SUV values during the axitinib holiday. Of 36 evaluable patients, there were 8 confirmed PRs by Response Evaluation Criteria in Solid Tumors. Overall, 20 patients had SD and 8 had PD as the best response. The median PFS was 8.7 months and the median overall survival was 14.0 months. Five BRAF(V600E/K) patients had significantly worse PFS than patients without these mutations.

CONCLUSIONS

Axitinib followed by carboplatin and paclitaxel was well tolerated and effective in BRAF wild-type metastatic melanoma. 3'-Deoxy-3'-(18)F-fluorothymidine-PET scans showed increased proliferation during axitinib withdrawal.

The Effect of Protease Inhibitors on Digestive Proteolytic Activity in the Raspberry Weevil, Aegorhinus superciliosus (Guérin) (Coleoptera: Curculionidae)

The raspberry weevil, Aegorhinus superciliosus (Guérin) (Coleoptera: Curculionidae), is an economically important pest of blueberry in southern Chile. The digestive protease activity of adult insects was investigated using general and specific substrates and inhibitors. Enzymatic assays demonstrated the presence of trypsin- and chymotrypsin-like serine proteinases. Furthermore, in vitro assays using phenylmethylsulfonyl fluoride (PMSF) and soybean trypsin inhibitor (SBTI) at 0.01 and 0.1 mM showed percentages of enzymatic inhibition between 0 and 16% for PMSF and 67 to 76% for SBTI, whereas in vivo assays indicated that SBTI caused between 50 and 90% mortality in males and between 80 and 100% in females. Our data indicate the presence of serine proteases and suggest that digestive proteases could be a target for the design and development of strategies to control the raspberry weevil.

Fungal volatiles: an environmentally friendly tool to control pathogenic microorganisms in plants

Fungi are an extraordinary and immensely diverse group of microorganisms that colonize many habitats even competing with other microorganisms. Fungi have received recognition for interesting metabolic activities that have an enormous variety of biotechnological applications. Previously, volatile organic compounds produced by fungi (FVOCs) have been demonstrated to have a great capacity for use as antagonist products against plant pathogens. However, in recent years, FVOCs have been received attention as potential alternatives to the use of traditional pesticides and, therefore, as important eco-friendly biotechnological tools to control plant pathogens. Therefore, highlighting the current state of knowledge of these fascinating FVOCs, the actual detection techniques and the bioactivity against plant pathogens is essential to the discovery of new products that can be used as biopesticides.

Morphology and Distribution of Sensilla on the Antennae of Hylamorpha elegans Burmeister (Coleoptera: Scarabaeidae)

Considering that sensilla constitute important functional elements of sensory systems in insects, the aim of this study was to determine the type and distribution of sensilla in the antennae of Hylamorpha elegans Burmeister examined by scanning electron microscopy. Hylamorpha elegans antennae are lamellate and consist of the scape, pedicel, and flagellum. The antennal club of this beetle consists of three terminal plates: proximal, middle, and distal lamellae. Four types of sensilla were observed in the lamellae from both sexes: sensilla trichoidea, chaetica, coeloconica, and placodea. Antennal length was larger in males than in females, and significant sexual variation in the number of sensilla placodea and sensilla coeloconica was observed.

Molecular Characterization and In Silico Analysis of the Pheromone-Binding Protein of the European Grapevine Moth Lobesia botrana (Denis & Schiffermüller) (Lepidoptera, Tortricidae)

The European grapevine moth Lobesia botrana (Denis & Schiffermüller) is an economically important insect in Europe. The species invaded vineyards in Chile, Argentina, and California during 2008-2010 causing severe problems. A major component of the sex pheromone, (E,Z)-7,9-dodecadienyl acetate (E7,Z9-12:Ac), is used in a mating disruption technique when grapevine moth populations are low or to monitor pest numbers. It is thought that these sexual pheromones are blends of volatiles that typically are specific to a species and are transported in the insect antenna by pheromone-binding proteins (PBPs) across the sensillar lymph to the olfactory receptors. Currently, an increasing number of Lepidopteran PBPs are being identified and cloned. However, there are no studies of the olfactory system and of proteins involved in the olfactory perception of L. botrana at the molecular level. In the present study, we report, for the first time, the sequence of a PBP from L. botrana (LbotPBP), which was determined using reverse transcription technology. Homology modeling was used to generate the three-dimensional protein structure. The model suggests that PBP consists of six α-helices as follows: Lys2-Met23 (α1), Thr28-Phe36 (α2), Arg46-Leu59 (α3), His70-Asn80 (α4), Glu84-Asn100 (α5), and Cys108-Lys125 (α6), held together by three disulfide bridges, Cys19-Cys54, Cys50-Cys108, and Cys97-Cys117. Docking simulations based on this model suggested that Trp114 is a key residue in the recognition of acetate pheromones, such as E7,Z9-12:Ac. In silico results in this study are consistent with previous findings in which E7,Z9-12:Ac acts as the most active compound in behavioral and electroantennographic assays.

GA3 stimulates the formation and germination of somatic embryos and the expression of a KNOTTED-like homeobox gene of Cocos nucifera (L.)

The micropropagation of coconut palm has progressed rapidly; yet, there are constraints with regard to the number of somatic embryos formed and their germination. To overcome these, we tested the effect of gibberellic acid and characterized genes of the KNOX family. Gibberellic acid at 0.5 muM increased 1.5-fold the number of calli forming somatic embryos and twofold the number of somatic embryos per callus, calli with germinating embryos and the number of germinating somatic embryos per callus. With regard to the study of KNOX family genes, the complete sequences of two KNOX-like genes were obtained for CnKNOX1 and CnKNOX2. The deduced amino acid sequence of both showed highly conserved domains characteristic of KNOX genes. CnKNOX1 showed high homology with KNOX class I proteins. CnKNOX1 expression was detected throughout the embryogenesis process except in somatic embryos at the pro-globular stage, and was highest in somatic embryos at the coleoptilar stage. No detection of CnKNOX1 expression occurred in calli with aberrant embryos. The addition of gibberellic acid stimulated the expression of CnKNOX1 earlier and the relative expression at all stages was higher. CnKNOX2 expression occurred at all stages peaking at the globular stage, but gibberellic acid treatment decreased the expression. Gene expression was also analyzed in tissues of different organs of adult palms. With CnKNOX1, high level of expression was found in tissues of organs with, but not in those without, meristem, whereas CnKNOX2 expression was detected in tissues with and also in those without meristem.

Olfactory response of Haematobia irritans (Diptera: Muscidae) to cattle-derived volatile compounds

In Chile, the horn fly, Hematobia irritans (L., 1758), is a major pest of grazing cattle and affects livestock production during the summer. Previous studies in Europe and the United States have shown that cattle flies, including H. irritans, are differentially attracted to individual cattle within herds and that volatile semiochemicals are responsible for this phenomenon. This study provides evidence that similar differential attractiveness occurs for the interaction between Chilean Holstein-Friesian cattle herds and local H. irritans populations. Thus, Holstein-Friesian dairy cattle, Bos taurus, which were of similar age and physiological condition, were shown to possess an uneven distribution of H. irritans. Heifers h6904 and h8104 were defined as low-carrier heifers and h5804, h2304 and h1404 as high-carrier heifers. Gas chromatography (GC) and coupled GC-mass spectrometric (GC-MS) analysis of samples collected from heifers revealed the presence of compounds previously reported as semiochemicals for cattle flies, including meta- and para-cresol, methylketones (C8-C11), and 6-methyl-5-hepten-2-one. Other compounds identified included carboxylic acids (butanoic, 3-methylbutanoic, pentanoic, and hexanoic acids), 1-hexanol, and 3-octanone. In Y-tube olfactometer studies, both m- and p-cresol attracted H. irritans at the highest doses tested (10(-6) g), as did the positive control 1-octen-3-ol. Of the other compounds tested, only 2-decanone and 2-undecanone produced a behavioral response, with significantly more flies being recorded in the control arm when the former compound was tested (at 10(-6) and 10(-8) g), and more flies being recorded in the treated arm for the latter compound (at 10(-7) g). This demonstration of behavioral activity with the identified compounds represents a first step for research into the application of semiochemicals in monitoring and control of cattle flies in Chile.

Insecticide resistance in the horn fly: alternative control strategies

The horn fly, Haematobia irritans (Linnaeus 1758) (Diptera: Muscidae) is one of the most widespread and economically important pests of cattle. Although insecticides have been used for fly control, success has been limited because of the development of insecticide resistance in all countries where the horn fly is found. This problem, along with public pressure for insecticide-free food and the prohibitive cost of developing new classes of compounds, has driven the investigation of alternative control methods that minimize or avoid the use of insecticides. This review provides details of the economic impact of horn flies, existing insecticides used for horn fly control and resistance mechanisms. Current research on new methods of horn fly control based on resistant cattle selection, semiochemicals, biological control and vaccines is also discussed.

Fungi test for evaluation of new antiandrogenic molecule

Antiandrogens have high impact in medicine as they are compounds capable of decreasing the effect of benign prostatic hyperplasia, cancer, and other androgen-dependent diseases that affect a large percentage of the male population in the world. [figure: see text] Dihydrotestosterone, a 5 alpha-reductase metabolite of testosterone, has been implicated as the responsible factor of these androgen abnormalities. This fact indicates that the logical step in the treatment of these diseases is the inhibition of this enzyme activity using molecules that compete selectively with its natural substrates. The study of the pharmacological effect of antiandrogens requires specific animal models using a large number of laboratory animals. On basis of this concept, presently there is a tendency to eliminate studies with animals. In this paper we report a new method for antiandrogenic evaluation using microbial transformations.

Antiandrogenic effect of new synthetic steroids

These results indicate that castration decreased the flank organ diameter and the weight of the seminal vesicles, whereas daily injection of testosterone restores them. However injections of finasteride together with testosterone inhibited the diameter of the flank organs, the weight of the seminal vesicles, and the conversion of testosterone to dihydrotestosterone. The four compounds tested inhibited flank organ diameter size and the weight of the seminal vesicles as compared to the testosterone-treated animals. On the other hand, none of these compounds suppressed the conversion of testosterone to dihydrotestosterone. These results suggest that the synthesized steroids compete with androgen receptors.

[Efficacy of clopidogrel as ADP-dependent platelet aggregation inhibitor. Study on individuals with coronary artery disease]

Acetyl-salicylic acid inhibits thromboxane A2 production and reduces the risk of vascular occlusive events by 20 to 25%. Ticlopidine inhibits ADP-dependent platelet aggregation and reduces the same risk by 30 to 35%, but produces some adverse effects. Clopidogrel is a ticlopidin-derived antiplatelet-drug, with the same mechanism of action; reduces the expression of the glycoprotein IIb/IIIa, the fibrinogen receptor on the platelet surface. Clopidogrel has the same clinical efficacy of ticlopidin and lowers the incidence of adverse effects. In this study, we evaluated the effects of one daily dosis of 75 mg of clopidogrel on platelet function in 33 subjects with coronary artery disease. Before treatment and after the 6th and 12th week, the following parameters were evaluated: 5 microM-ADP and 20 micrograms/mL collagen-induced platelet aggregation, bleeding time and fibrinogen concentration. In basal and in the 6th and 12th week samples, ADP-induced platelet aggregation was 90.7% +/- 13.2, 54.6% +/- 23.2 and 49.2% +/- 23.7 respectively, that represents a significant reduction of 38.6% and 44.4%. Reduction of collagen-induced platelet aggregation was not significative. Plasmatic fibrinogen did not suffer variation during treatment. Bleeding time was significant prolonged from 4.1 minutes to 15.4 and 14.6 minutes (3.7-3.5 times compared with the test before treatment). There were no haemorrhagic complications, only digestive discomfort in fewer than 3% of patients. We concluded that clopidogrel is a safe and efficacious drug for patients, it efficiently reduces ADP-induced platelet aggregation and prolongs bleeding time.

Synthesis and pharmacological evaluation of 4-halo progesterone derivatives as antiandrogen

The pharmacological activity of eight pregnane derivatives 17-alpha acetoxyprogesterone 9, 17-alpha acetoxy-4, 5-epoxypregnan-3, 20-dione 10, 17-alpha acetoxy-4-chloro-4-pregnene-3, 20-dione 11, 17-alpha acetoxy-4-bromo-4-pregnene-3, 20-dione 12, 17-alpha hydroxy-4-bromo-4-pregnene-3, 20-dione 13, 4-chloro-17-alpha hydroxy-4-pregnene-3, 20-dione 14, 17-alpha benzoyloxy-4-bromo-4-pregnene-3, 20-dione 15 and 17-alpha benzoyloxy-4-chloro-4-pregnene-3, 20-dione 16 was determined. These compounds were evaluated as antiandrogens on gonadectomized hamster seminal vesicles. The pharmacological data in this study indicate that compounds 15 and 16 having a C-17 benzoyloxy moiety showed the highest antiandrogenic activity as measured by the reduction of the weight of the seminal vesicles, followed by the steroids 11 and 12 (17-alpha acetoxy group). The free alcohols 13 and 14 exhibited a lower antiandrogenic activity. Apparently, the ester moiety at C-17 is a necessary requirement for the presence of high antiandrogenic activity. Shows the inhibitory effect on the conversion of testosterone (T) to DHT, of the above described steroids as measured by the amount of produced DHT 2 expressed as pmoles of DHT/g of protein/h. Steroids 11, 12 and 16 showed a much higher inhibitory activity on the conversion of testosterone (T) to dihydrotestosterone (DHT) than presently used finasteride 3.

Absorption and excretion of cefquinome in coho salmon (Oncorhynchus kisutch) in freshwater at 10 degrees C

The absorption and elimination of cefquinome in serum and tissues of coho salmon were studied. The study was performed in freshwater at 10 degrees C with fish weighing 100 +/- 5 g (mean and standard deviation). Single doses of 5, 10 and 20 mg/kg were administered intraperitoneally to 30 fish for each dose. The maximum concentration occurred in the following order; kidney and liver > serum > muscle > brain. The pharmacokinetic analysis and predictive withdrawal times were calculated using only the dose of 20 mg/kg body weight. The peak cefquinome concentrations (Cmax) in serum (3.35 +/- 0.45 micrograms/ml) and muscle (2.87 +/- 0.53 micrograms/g) were achieved at 12 h. In the brain, the Cmax was 2.18 micrograms/g at 6 h. The half-lives (t1/2) in serum, muscle, brain, liver and kidney were 20.56, 8.93, 9.35, 113.61 and 119.48 h, respectively. With the detection limit of 0.015 microgram/g for the cefquinome, the predicted withdrawal time with 95% confidence for muscle tissue was 104.2 h at 10 degrees C for the 20 mg/kg dose. The results suggest that cefquinome could be efficacious and safe for the consumer in treating bacterial diseases of coho salmon in fresh water. Nevertheless, future studies are required in order to determine an adequate dose with the corresponding withdrawal times.

A submaximal treadmill test for developing target ratings of perceived exertion for outpatient cardiac rehabilitation

For patient populations whose heart rates cannot be used to regulate exercise intensity, the Borg Rating of Perceived Exertion (RPE) Scale is the preferred way to prescribe exercise intensity. Individual perceptual variations are best quantified by measuring perceptual intensity during maximal exercise testing; however, many situations require a submaximal protocol. Here, a submaximal treadmill procedure for establishing individualized target Ratings of Perceived Exertion is described. Target ratings of exertion were developed for outpatient cardiac rehabilitation patients using the new method and compared to target Ratings of Perceived Exertion obtained using standard techniques. A total of 144 target ratings at intensities ranging from 50% to 85% VO2max were compared. Over-all, the average difference between the two methods was 0.27 units and was not significant at any intensity. Therefore, the Treadmill Slope Method appears to be a valid submaximal test for generating target Ratings of Perceived Exertion for outpatient cardiac rehabilitation patients.

[Serum hepatitis B markers in blood donors in Venezuela. What do they mean?]

PURPOSE

The prevalence of serum BH markers is high in our country. In order to assess the factors of impact in this fact a group of blood donors with positive BH markers attending our Service between 1-1-95 and 12-31-96 was evaluated, although the endemic character of the disease may be an obstacle for its recognition. The residual risk of HBV transmission by seronegative transfusions was also evaluated.

MATERIAL AND METHODS

The evaluation of donors was performed by surveying identification data, type and frequency of donations and risk factors. The following reagents were used to carry out the bests: Biotest Elisa HbsAgand Heprofile anti HBc, ADI Diagnostics (1995), and Abbott Auzyme Monoclonal and Abbott Corzyme Diagnostic kit. Positive donors were re-evaluated to determine any progression of the disease and they were classified into false positive (FP), chronic carriers (CC), acute hepatitis (AH), naturally immunized (NI), or without evidence of immunity (WI). The residual transfusional risk was calculated by multiplying the adjusted prevalence of HbsAg positive donors by the window period expressed in fractions of a year.

RESULTS

Out of 53,338 donations, 5.91% were discarded due to the presence of HBV, 7.5% of them showing significant association with other markers: HCV, Chagas' disease and syphilis. Of all donors 223 (7.54%) returned for re-evaluation, and only 139 (62.33% of them) could be fully evaluated as follows: FP 10.09%, AH 5.76%, CC 7.19%, NI 68.35%, WI 7.91%. Their mean age was 35.73 +/- 9.95 years, and there were 112 males and 12 females. The donations were patient-related in 93.5% of cases, voluntary in 3.22% and coming from mobile units in 3.22% of instances (p = 0.067). Fifth per cent donated for the first time, and the other 50% had donated previously although not in a consecutive way (p = 0.96): 46% were ignorant of their post-donation findings, 37.09% were seemingly negative and 16.12% had positive tests. Of these last, the reasons for donation included defective questioning and information (50%), results not verified (20%) and family/hospital pressure (30%). Homo/bisexuality and drug abuase (not intravenous) were found significant when associated to each other or to promiscuity. Promiscuity attained significant risk value, especially when previous venereal disease or close contact with BH patients were presented (p = 0.0015, p = 0.155, and p = 0.0036, respectively). The residual risk of transmitting HBV by seronegative transfusions was found to be: 1:437.

CONCLUSIONS

1. No risk factors were detected in a half of the cases. 2. The other half, comprising the known seropositive subjects and the promiscuous, homo/bisexual donors and those having close contact with HBV patients, can be discarded predonation. 3. Drug abuse (not intravenous), frequently associated with other risk factors, should discard a donor. 4. History of veneral disease should be considered a risk factor due to its common association to HBV. 5. The residual risk of acquiring HBV post-transfusion is still high.

RECOMMENDATIONS

1. To improve the information provided to donors regarding the risk factors. 2. The interrogation should be simple, direct and deep. 3. To insist in the importance of the donor returning for his/her credentials in the blood bank and to know about any altered results, and to seek medical advice when appropriate. 4. To change related donation into a voluntary and consecutive pattern.

[Tetralogy of Fallot in adults]

We present the clinical and hemodynamic profile of 33 patients, older than the 18 year with tetralogy of Fallot. Cardiac catheterization and selective angiocardiography were performed in all cases. We excluded patients with valvular pulmonary atresia associated with tetralogy of Fallot. Most of the patients were in functional class II or IV of the New York Heart Association and all presented with cyanosis. In the electrocardiogram of 23 patients we found right bundle branch block. None had significant cardiomegaly, 19 of 20 cases had reduced pulmonary blood flow and reticular pattern in the lung fields as observed in the chest X-ray. We did not find correlation between the age and the degree of cyanosis, but the level of arterial desaturation correlated with the functional class. The right ventricular systolic pressure was elevated in all patients. In all cases but one the pulmonary arterial systolic pressure were normal of slightly increased. One case with mild pulmonary infundibular stenosis had pulmonary systolic pressure similar to the systemic pressure. Multivariate analysis for functional class showed significant value for cyanosis. Systemic-pulmonary shunt was performed in 10 patients with hypoplastic pulmonary arteries plus reduced pulmonary blood flow, with one postoperative death. We did not find postoperative mortality in patients who underwent corrective surgery. The anatomic and functional behavior of patients who underwent surgery, allowed better tolerance to their heart defects.

Circadian variation in blood pressure and heart rate in nonhypertensive congestive heart failure

This study was designed to determine whether decreases in the circadian variability of arterial blood pressure and heart rate measured in ambulatory patients would correlate with neurohumoral indices of the severity of congestive heart failure not the result of systemic arterial hypertension, and whether treatment with angiotensin-converting enzyme (ACE) inhibitors would restore a more normal pattern. The study also examined the ability of ambulatory blood pressure monitoring to discern pharmacodynamic patterns in patients with congestive heart failure, which is associated with decreased variability in circadian variations in blood pressure and heart rate among hospitalized patients. Increased plasma norepinephrine, renin activity, and atrial natriuretic peptide (ANP) have a positive correlation with worsening clinical status. ACE inhibitors have been found to be beneficial in the treatment of congestive heart failure. Ambulatory 24-h blood pressure and neurohumoral measurements were recorded in 30 patients with congestive heart failure (class II-IV, New York Heart Association) before treatment with lisinopril or captopril and repeated after 6 weeks of treatment. Fourier analysis was used as a curve-smoothing technique to compare the pharmacodynamics of the two ACE inhibitors. The absolute amplitude of systolic blood pressure correlated inversely with plasma norepinephrine and ANP (p = 0.004) but not with renin activity. Mean 24-h systemic arterial blood pressure did not decrease significantly after treatment with ACE inhibitors. An increase in absolute amplitude of systolic blood pressure correlated inversely with baseline amplitude (p < 0.00001). Inspection of the Fourier-smoothed curves demonstrated differences in the circadian effect of lisinopril and captopril on systolic blood pressure and rate-pressure product. Ambulatory 24-h blood pressure monitoring may prove useful in the assessment of the severity and treatment of congestive heart failure.

Three-point method of prescribing exercise with ratings of perceived exertion is valid for cardiac patients

It is often difficult to use heart rate to prescribe exercise for cardiac patients due to the effects of medications and procedures such as cardiac transplantation. Ratings of Perceived Exertion (RPE) is the preferred method of regulating exercise intensity in these situations. An RPE-based exercise prescription has previously depended on perceptual data from a maximal Graded Exercise Test (GXT). Recently, using 13 healthy subjects, we validated a Three-point RPE for prescribing exercise using RPE which can be used when ratings from a GXT are not available Currently, we examined the accuracy of this method for developing target RPEs for patients in Phase II cardiac rehabilitation. Such target RPEs did not differ from those obtained using standard procedures. We conclude that the Three-point Method is valid for preparing RPE-based exercise prescriptions for Phase II cardiac rehabilitation patients.

New cytotaxonomical determinants recognized in six taxa of Agave in the sections Rigidae and Sisalanae

New cytotaxonomical determinants are presented for the following taxa of Agave: (I) section Rigidae: Agave fourcroydes Lemaire (5x = 150), first karyotype; Agave angustifolia Haworth (sensu Gentry), new count (6x = 180), first karyotype; Agave angustifolia Haworth var. marginata Hort. (2x = 60); and Agave tequilana Weber, new count (2x = 60), first karyotype; (II) section Sisalanae: Agave sisalana Perrine (5x = 150), first karyotype; and (III) intersectional hybrid: Agave hybrid 11 648 new count (2x = 60), first karyotype. Chromosomes are classified and arm number, chromatin length, and variability are discussed. These results suggest (i) a speciation process via limited rearrangements and point mutations in the small chromosomes of the complement, within the euploidy level rather than karyotype diversification and (ii) a reconsideration to assign them to the 2C level of Stebbins karyotype classification. Key words: fiber agaves, karyotype analysis.

Acute and short-term effects of clonidine in heart failure

The authors performed a randomized, double-blind, placebo-controlled trial to assess the tolerance and effects of chronic oral clonidine administration on the clinical status, exercise tolerance, and ventricular function of 10 male patients with chronic heart failure. Patients were given either oral clonidine (400 micrograms/day) or matching placebo for twelve weeks and then tapered off medication over a two-week period. Results are summarized as follows: Profiles over time between groups were significantly different for resting heart rate (p = 0.0005), were different for arterial pressure (p = 0.04), were different for left ventricular ejection fraction (p less than 0.006), and were different for mean accumulated workload (p = 0.076). Exercise double product at 25 watts changed little in three patients and showed a decrease in 2 patients following six weeks of oral clonidine; after twelve weeks, it decreased in three patients, increased in 1, and changed little in another. After washout, double product returned toward baseline values. In the placebo groups, double product showed little change. Resting of the heart by decreasing heart rate, systemic arterial blood pressure, and venous tone are thought by the authors to be major contributing factors to the observed beneficial effect of chronic oral clonidine in chronic heart failure.