CLIMATOLOGICAL HYDRIC BALANCE, EFFECTIVE SOIL WATER STORAGE AND TRANSPIRATION IN COFFEE CULTURE

The climatic water balance is one of the most used tools to assess, indirectly the amount of water present in the soil is capable of meeting the water needs of the plant. This study analyzed the climatologic hydric balance, the effective soil water storage and coffee plant transpiration in dry regimen cultivation. Daily climatologic hydric balance was calculated for coffee from January 2003 to May 2006. It was concluded that even in the most rainy months of the year, there is a hydric deficit in coffee plants grown in a dry regimen; effective soil water storage varied greatly through the years evaluated, and September was the most critical month, when this value remained below 30%; relative transpiration can not be taken as the single evaluation method for yield losses of coffee, grown in a dry regimen.

Effective Tityus serrulatus anti-venom produced using the Ts1 component

Scorpion stings are a public health problem in Brazil, with most incidents involving the species Tityus serrulatus. Some T serrulatus toxins may act as immunogens for the production of a specific anti-venom, but many of the component toxins remain poorly characterized. Here, we describe the immunological characteristics of the toxin Ts1 (also known as TsVII and Ts-gamma) and evaluate production of neutralizing antibodies against the crude venom of T serrulatus. Recombinant Ts1 with one copy (Ts1((1))) or two copies in tandem (Ts1((2))) was expressed in BL21 (DE3) cells. Rabbits and mice were immunized with the recombinant proteins (inclusion bodies) and then tested for production of neutralizing antibodies. Neutralization assays showed that anti-Ts1((1)) and anti-Ts1((2)) protected animals challenged with T serrulatus crude venom and native Ts1 Thus, Ts1 could be used in a mixed ""cocktail"" of immunogens for T serrulatus anti-venom production. (C) 2008 Elsevier Ltd. All rights reserved.

On the mechanisms of phenothiazine-induced mitochondrial permeability transition: Thiol oxidation, strict Ca(2+) dependence, and cyt c release

Phenothiazines (PTZ) are drugs widely used in the treatment of schizophrenia. Trifluoperazine, a piperazinic PTZ derivative, has been described as inhibitor of the mitochondrial permeability transition (MPT). We reported previously the antioxidant activity of thioridazine at relatively low concentrations associated to the inhibition of the MPT (Brit. J. Pharmacol., 2002;136:136-142). In this study, it was investigated the induction of MPT by PTZ derivatives at concentrations higher than 10 mu M focusing on the molecular mechanism involved. PTZ promoted a dose-response mitochondrial swelling accompanied by mitochondrial transmembrane potential dissipation and calcium release, being thioridazine the most potent derivative. PTZ-induced MPT was partially inhibited by CsA or Mg(2+) and completely abolished by the abstraction of calcium. The oxidation of reduced thiol group of mitochondrial membrane proteins by PTZ was upstream the VIP opening and it was not sufficient to promote the opening of PTP that only occurred when calcium was present in the mitochondrial matrix. EPR experiments using DMPO as spin trapping excluded the participation of reactive oxygen species on the PTZ-induced MPT. Since 117 give rise to cation radicals chemically by the action of peroxidases and cyanide inhibited the PTZ-induced swelling, we propose that VIZ bury in the inner mitochondrial membrane and the chemically generated 117 cation radicals modify specific thiol groups that in the presence of Ca(2+) result in MPT associated to cytochrome c release. These findings contribute for the understanding of mechanisms of MET induction and may have implications for the cell death induced by PTZ. (C) 2010 Elsevier Inc. All rights reserved.

Impact of adenosine nucleotide translocase (ANT) proline isomerization on Ca(2+)-induced cysteine relative mobility/mitochondrial permeability transition pore

Mitochondrial membrane carriers containing proline and cysteine, such as adenine nucleotide translocase (ANT), are potential targets of cyclophilin D (CyP-D) and potential Ca(2+)-induced permeability transition pore (PTP) components or regulators; CyP-D, a mitochondrial peptidyl-prolyl cis-trans isomerase, is the probable target of the PTP inhibitor cyclosporine A (CsA). In the present study, the impact of proline isomerization (from trans to cis) on the mitochondrial membrane carriers containing proline and cysteine was addressed using ANT as model. For this purpose, two different approaches were used: (i) Molecular dynamic (MD) analysis of ANT-Cys(56) relative mobility and (ii) light scattering techniques employing rat liver isolated mitochondria to assess both Ca(2+)-induced ANT conformational change and mitochondrial swelling. ANT-Pro(61) isomerization increased ANT-Cys(56) relative mobility and, moreover, desensitized ANT to the prevention of this effect by ADP. In addition, Ca(2+) induced ANT ""c"" conformation and opened PTP; while the first effect was fully inhibited, the second was only attenuated by CsA or ADP. Atractyloside (ATR), in turn, stabilized Ca(2+)-induced ANT ""c"" conformation, rendering the ANT conformational change and PTP opening less sensitive to the inhibition by CsA or ADP. These results suggest that Ca(2+) induces the ANT ""c"" conformation, apparently associated with PTP opening, but requires the CyP-D peptidyl-prolyl cis-trans isomerase activity for sustaining both effects.

Dehydromonocrotaline induces cyclosporine A-insensitive mitochondrial permeability transition/cytochrome c release

Monocrotaline (MCT) is a pyrrolizidine alkaloid present in plants of the genus Crotalaria that causes cytotoxicity and genotoxicity in animals and humans. It is well established that the toxicity of MCT results from its hepatic bioactivation to dehydromonocrotaline (DHM), an alkylating agent, but the exact mechanism of action remains unknown. In a previous study, we demonstrated DHM`s inhibition of mitochondrial NADH-dehydrogenase activity at micromolar concentrations, which is an effect associated with a significant reduction in ATP synthesis. As a follow-up study, we have evaluated the ability of DHM to induce mitochondrial permeability transition (MPT) and its associated processes in isolated rat liver mitochondria. In the presence of 10 mu M Ca(2+), DHM (50-250 mu M) elicited MPT in a concentration-dependent, but cyclosporine A-independent manner, as assessed by mitochondrial swelling, which is associated with mitochondrial Ca(2+) efflux and cytochrome c release. DHM (50-250 mu M) did not cause hydrogen peroxide accumulation but did deplete endogenous glutathione and NAD(P)H, while oxidizing protein thiol groups. These results potentially indicate the involvement of mitochondria, via apoptosis, in the well-documented cytotoxicity of monocrotaline. (C) 2009 Elsevier Ltd. All rights reserved.

Ca(2+) binding to c-state of adenine nucleotide translocase (ANT)-surrounding cardiolipins enhances (ANT)-Cys(56) relative mobility: A computational-based mitochondrial permeability transition study

The oxidation of critical cysteines/related thiols of adenine nucleotide translocase (ANT) is believed to be an important event of the Ca(2+)-induced mitochondrial permeability transition (MPT), a process mediated by a cyclosporine A/ADP-sensitive permeability transition pores (PTP) opening. We addressed the ANT-Cys(56) relative mobility status resulting from the interaction of ANT/surrounding cardiolipins with Ca(2+) and/or ADP by means of computational chemistry analysis (Molecular Interaction Fields and Molecular Dynamics studies), supported by classic mitochondrial swelling assays. The following events were predicted: (i) Ca(2+) interacts preferentially with the ANT surrounding cardiolipins bound to the H4 helix of translocase, (ii) weakens the cardiolipins/ANT interactions and (iii) destabilizes the initial ANT-Cys(56) residue increasing its relative mobility. The binding of ADP that stabilizes the conformation ""m"" of ANT and/or cardiolipin, respectively to H5 and H4 helices, could stabilize their contacts with the short helix h56 that includes Cys(56), accounting for reducing its relative mobility. The results suggest that Ca(2+) binding to adenine nucleotide translocase (ANT)-surrounding cardiolipins in c-state of the translocase enhances (ANT)-Cys(56) relative mobility and that this may constitute a potential critical step of Ca(2+)-induced PTP opening. (C) 2009 Elsevier B.V. All rights reserved.

Pollen abortion rates, nitrogen dioxide by passive diffusive tubes and bioaccumulation in tree barks are effective in the characterization of air pollution

This study aims to evaluate the feasibility of using simple techniques - pollen abortion rates, passive diffusive tubes (NO(2)) and trace element accumulation in tree barks - when determining the area of influence of pollution emissions produced in a traffic corridor. Measurements were performed at 0, 60 and 120 meters from a major road with high vehicular traffic, taking advantage of a sharp gradient that exists between the road and a cemetery. NO(2) values and trace elements measured at 0 meters were significantly higher than those measured at more distant points. Al, S. Cl, V. Fe, Cu, and Zn exhibited a higher concentration in tree barks at the vicinity of the traffic corridor. The same pattern was observed for the pollen abortion rates measured at the three different sites. Our data suggests that simple techniques may be applied either to validate dispersion land-based models in an urban settings or, alternatively, to provide better spatial resolution to air pollution exposure when high-resolution pollution monitoring data are not available. (C) 2011 Elsevier B.V. All rights reserved.

PHRENIC NERVE TRANSFER IN THE RESTORATION OF ELBOW FLEXION IN BRACHIAL PLEXUS AVULSION INJURIES: HOW EFFECTIVE AND SAFE IS IT?

OBJECTIVE: Phrenic nerve transfer has been used for treating lesions of the brachial plexus since 1970. Although, today, surgeons are more experienced with the technique, there are still widespread concerns about its effects on pulmonary function. This study was undertaken to evaluate the effectiveness and safety of this procedure. METHODS: Fourteen patients with complete palsy of the upper limb were submitted to phrenic nerve transfer as part of a strategy for surgical reconstruction of their plexuses. Two patients were lost to follow-up, and 2 patients were followed for less than 2 years. Of the remaining 10 patients, 9 (90%) were male. The lesions affected both sides equally. The mean age of the patients was 24.8 years (range, 14-43 years), and the mean interval from injury to surgery was 6 months (range, 3-9 months). The phrenic nerve was always transferred to the musculocutaneous nerve, and a nerve graft (mean length, 8 cm; range, 4.5-12 cm) was necessary in all cases. RESULTS: There was no major complication related to the surgery. Seven patients (70%) recovered functional level biceps strength (Medical Research Council grade >= 3). All of the patients exhibited a transient decrease in pulmonary function tests, but without clinical respiratory problems. CONCLUSION: On the basis of our small series and data from the literature, we conclude that phrenic nerve transfer in well-selected patients is a safe and effective procedure for recovering biceps function.

Laparoscopic extended cardiomyotomy in children: an effective procedure for the treatment of esophageal achalasia

Purpose: Achalasia of the esophagus is characterized by aperistalsis and incomplete relaxation of the lower esophageal sphincter in response to swallowing. The objective of the present study is to present the experience of a modified Heller myotomy via a laparoscopic approach for the treatment of children who had this condition. Methods: A retrospective review of medical records of all patients who underwent this procedure from 2000 to 2009 was performed. The procedure consisted of an extended esophagomyotomy beginning on the lower part of the lower esophageal sphincter and continuing 5 to 6 cm above on the lower third of the esophagus, and then extended 3 to 4 cm below to the stomach, associated with an anterior 180-degree hemi-fundoplication according to Dor`s technique. Results: Fifteen patients were included in the study. There were 8 female and 7 male patients. Mean operating time was 190 minutes with no intraoperative complications and 1 conversion to open surgery because of difficulty in dissecting an inflamed distal esophagus. In a mean follow-up period of 32.3 months, 2 patients had recurrence of mild dysphagia that disappeared spontaneously, and 1 required a single botulinum toxin injection with complete resolution of symptoms. Conclusion: We conclude that the laparoscopic extended Heller myotomy with Dor fundoplication is a safe and effective method for the treatment for achalasia in the pediatric population even in advanced cases. (C) 2010 Elsevier Inc. All rights reserved.

Role of nitric oxide in hyperpnea-induced bronchoconstriction and airway microvascular permeability in guinea pigs

The present study aimed to evaluate the role of nitric oxide (NO) on hyperpnea-induced bronchoconstriction (HIB) and airway microvascular hyperpermeability (AMP). Sixty-four guinea pigs were anesthetized, tracheotonnized, cannulated, and connected to animal ventilator to obtain pulmonary baseline respiratory system resistance (Rrs). Animals were then submitted to 5 minutes hyperpnea and Rrs was evaluated during 15 minutes after hyperpnea. AMP was evaluated by Evans blue dye (25 mg/kg) extravasation in airway tissues. Constitutive and inductible NO was evaluated by pretreating animals with N(G)-nitro-1-arginine methyl ester (I-NAME) (50 mg/kg), aminoguadinine (AG) (50 mg/kg), and I-arginine (100 mg/kg) and exhaled NO (NOex) was evaluated before and after drug administration and hyperpnea. The results show that I-NAME potentiated (57%) HIB and this effect was totally reversed by I-arginine pretreatment, whereas AG did not have effect on HIB. I-NAME decreased basal AMP (48%), but neither I-NAME nor AG had any effect on hyperpnea-induced AMP. NOex levels were decreased by 50% with I-NAME, effect that was reversed by I-arginine treatment. These results suggest that constitutive but not inducible NO could have a bronchoprotective effect on HIB in guinea pigs. The authors also observed that neither constitutive nor inducible NO seems to have any effect on hyperpnea-induced AMP.

Peginterferon alfa-2b and Ribavirin: Effective in Patients With Hepatitis C Who Failed Interferon alfa/Ribavirin Therapy

Background & Aims: Treatment with peginterferon alfa and ribavirin produces a sustained virologic response (SVR) in approximately 60% of hepatitis C virus (HCV)-infected patients. Alternate options are needed for patients who relapse or do not respond to therapy. Methods: This prospective, international, multicenter, open-label study evaluated efficacy and safety of peginterferon alfa-2b (1.5 mu g/kg/wk) plus weight-based ribavirin (800-1400 mg/day) in 2333 chronic HCV-infected patients with significant fibrosis/cirrhosis whose previous interferon alfa/ribavirin therapy failed. Patients with undetectable HCV-RNA at treatment week (TW) 12 received 48 weeks of therapy; patients with detectable HCV-RNA at TW12 could enter maintenance studies at TW18; 188 patients with low/detectable HCV-RNA at TW12 continued therapy at the investigator`s request. Results: Overall, 22% of the patients attained SVR (56% with undetectable HCV-RNA and 12% with low/detectable HCV-RNA at TW12). SVR was better in relapsers (38%) than nonresponders (14%), regardless of previous treatment, and in patients previously treated with interferon-alfa/ribavirin (25%) than peginterferon alfa-ribavirin (17%). Predictors of response in patients with undetectable HCV-RNA at TW12 were genotype (2/3 vs 1, respectively; odds ratio [OR] 2.4; P < .0001), fibrosis score (F2 vs F4; OR, 2.2; F3 vs F4; OR, 1.7; P < .0001), and baseline viral load (<= 600,000 vs >600,000 IU/mL; OR, 1.4; P = .0223). These factors plus previous treatment and response were overall predictors of SVR. Safety was similar among fibrosis groups. Conclusions: Peginterferon alfa-2b plus weight-based ribavirin is effective and safe in patients who failed interferon alfa/ribavirin therapy. Genotype, baseline viral load, and fibrosis stage were predictors of response.

Is the combination of mitomycin C, bleomycin and methotrexate effective as a neoadjuvant treatment for cervical cancer in women?

Objective: To determine the effectiveness of the combination of mitomycin C, bleomycin and methotrexate as a neoadjuvant treatment in preparation for surgical treatment of cervical cancer. Methods and Materials: Twenty-seven patients with carcinoma of the uterine cervix (stages exophytic IB2 and IIB-IIIB) who had not previously undergone any treatment received mitomycin C, bleomycin and methotrexate in five sessions, once every four weeks. Results: The objective response rate was approximately 81%, including 16 complete responses and six partial responses. Significant toxic effects were not observed. Responsive patients underwent surgery and remained without evidence of disease for the next 20 years. Unresponsive patients did not fare well and passed away within five years after treatment. Conclusion: Our data suggest that this strategy may be effective for advanced cases, enabling patients to receive surgical treatment.

The need for effective radiosentitizing agents: experience in patients with complete pathological response

Chemoradiation therapy is now considered the preferred initial treatment strategy for distal rectal cancer because of the observation of better local disease control and significant tumor downstaging. Downstaging has become an important clinical outcome as patients with complete pathological response are associated with improved survival. Even though radiation alone may result in low local recurrence rates, the use of additional radiosensitizing agents may provide an increase in local disease control in addition to improved tumor regression rates. Several compounds have been investigated in the setting of neoadjuvant multimodality treatment of rectal cancer with variable rates of treatment-related toxicity and complete pathological response. The balance between complete pathological response and toxicity should aid in the management decision for the use of radiosensitizing agents in the neoadjuvant setting for the treatment of rectal cancer. Anti-Cancer Drugs 22: 308-310 (C) 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Is the wearing of elastic stockings for half a day as effective as wearing them for the entire day?

P>Background There is good evidence for the use of compression for some clinical indications but little is known about dosimetry in compression. Objective The aim of this work was to evaluate whether or not the use of compression stockings during part of the day would help in the reduction of evening oedema in patients with clinical, epidemiological, anatomical and physiopathological (CEAP) classifications C0 and C1. Methods The effects of elastic compression stockings on volumetric variations during the working day were evaluated for the legs of two men and 18 women (40 legs). The inclusion criterion was classification as C0 (10 legs) or C1 (30 legs) according to the CEAP criteria. Participants used three-quarter-length elastic compression stockings (20-30 mmHg) on three consecutive days for the entire day or only for the morning or they did not use the stockings at all. Volumetry using the water displacement technique was performed in the morning and in the evening. When the patients wore the stockings only during the morning, volumetry was also performed at 13:00 h. Results Significant increases in volume were observed for both legs when stockings were not used compared with the use of stockings in the morning only. After removing the stockings, both legs had significant increases in volume in the afternoon. However, use for half the day was better than not using the stockings at all. Conclusions The use of elastic compression stockings can reduce volumetric variations during working hours, with the use of stockings for the entire day being better than for just half the day.