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1.
Anal Bioanal Chem ; 415(23): 5781-5795, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37498327

ABSTRACT

Hydrogen peroxide (H2O2) plays a role in many facets - a household item, an important industrial chemical, a biomarker in vivo, and several others. For this reason, its measurement and quantification in a variety of media are important. While spectroscopic detection is primarily used for H2O2, electrochemical methods offer advantages in versatility, cost, and sensitivity. In this work, we investigate a 2-step surface metal nanoparticle (NP) modification for platinum (Pt) and palladium (Pd) on boron-doped diamond (BDD) electrodes for the detection of H2O2. Several parameters such as the metal salt concentration and electrodeposition charge in the 2-step modification were varied to find an optimum. Using cyclic voltammetry (CV), the BDD-PdNP electrode types were found to yield a sharper, more well-resolved H2O2 oxidation peak compared to the BDD-PtNP electrodes. Both metal NP electrode types significantly improved the response compared to the bare BDD electrode; a 150-200× improvement in sensitivity was observed across all modified electrode types. Calibration experiments were completed at both low and high concentration ranges in stagnant and flow-based solutions. The lowest limit of detection (LOD) obtained was 50 nM (5E-08 M) on a BDD-PdNP electrode modified with 1.0 mM PdCl2 to 5.0 mC in the wet chemical seeding and electrodeposition steps. 0.25 mM PdCl2 to 3.23 mC and 0.25 mM HPtCl6- to 3.23 mC also yielded a sufficient response for low-level H2O2, with LODs around 100 nM (1E-07 M). Overall, this work exemplifies the wide applicability of BDD and achieves sub-µM H2O2 LODs with a non-enzymatic electrode material.

2.
P R Health Sci J ; 42(2): 146-151, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37352537

ABSTRACT

OBJECTIVE: This article proposes an engineering-economics model to determine the total cost of a neurological disease along its temporal progression. The objective was to develop a planning tool faithful to the reality of this type of ailment as well as to that of Puerto Rico (PR). METHODS: The proposed model organizes a given neurological disease into 3 progressive phases of deterioration; in each, the model collects the typical associated costs and adjusts them based on their value over time. This way, the total cost of the ailment is calculated and its present day dollar value expressed. Model verification was carried out using data from Puerto Rico related to Parkinson's, Alzheimer's, and Huntington's diseases. RESULTS: The method demonstrated here considered Parkinson's disease in PR. Our model calculated a total annual cost of $64,915 for a patient at the medium stage. This figure is larger than estimates from other authors, which fall between $41,689 and $51,600 for the USA. This difference is partially due to the proposed model considering the individual's opportunity cost of the loss of productive years, an original contribution of our work. CONCLUSION: A neurological disease is one in which an individual goes through progressive phases of deterioration that will require significant economic resources. The model proposed here is designed across the commonalities between Alzheimer's, Parkinson's, and Huntington's diseases and illustrated using costs from PR. As an additional contribution, it allows the consideration of the opportunity cost of lost productivity, a characteristic that makes it more realistic.


Subject(s)
Alzheimer Disease , Huntington Disease , Nervous System Diseases , Parkinson Disease , Humans , Huntington Disease/epidemiology , Puerto Rico
3.
Antibiotics (Basel) ; 12(1)2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36671307

ABSTRACT

Invasive candidiasis is an important cause of morbidity and mortality, and its occurrence is increasing due to the growing complexity of patients. In particular, Candida albicans exhibits several virulence factors that facilitate yeast colonization in humans. In this sense, the photodynamic inactivation of yeasts is a promising new alternative to eliminate fungal infections. Herein, the photodynamic activity sensitized by a free-base chlorin (TPCF16) and its complexes with Zn(II) (ZnTPCF16) and Pd(II) (PdTPCF16) was investigated in order to eliminate C. albicans under different forms of cell cultures. A decrease in cell survival of more than 5 log was found in planktonic cells incubated with 5 µM TPCF16 or ZnTPCF16 upon 15 min of white-light irradiation. The mechanism of action mainly involved a type II pathway in the inactivation of C. albicans cells. In addition, the photodynamic action induced by these chlorins was able to suppress the growth of C. albicans in a culture medium. These photosensitizers were also effective to photoinactivate C. albicans pseudohyphae suspended in PBS. Furthermore, the biofilms of C. albicans that incorporated the chlorins during the proliferation stage were completely eradicated using 5 µM TPCF16 or ZnTPCF16 after 60 min of light irradiation. The studies indicated that these chlorins are effective photosensitizing agents to eliminate C. albicans as planktonic cells, pseudohyphae, and biofilms.

4.
Org Biomol Chem ; 19(27): 6007-6014, 2021 07 14.
Article in English | MEDLINE | ID: mdl-34165127

ABSTRACT

An azide and transition metal-free method for the synthesis of elusive phosphonic, phosphinic, and phosphoric monoacids has been developed. Inert pentavalent P(v)-compounds (phosphonate, phosphinate, and phosphate) are activated by triflate anhydride (Tf2O)/pyridine system to form a highly reactive phosphoryl pyridinium intermediate that undergoes nucleophilic substitution with H2O to selectively deprotect one alkoxy group and form organophosphorus monoacids.

5.
Biomedica ; 40(2): 336-348, 2020 06 15.
Article in English, Spanish | MEDLINE | ID: mdl-32673461

ABSTRACT

INTRODUCTION: Essential amino acid α-keto acid analogs are used in the treatment of chronic kidney disease to delay the symptoms of uremia. However, it is unknown whether essential amino acid α-keto acid analogs affect the oxidative stress and the inflammation in acute renal injury such as those produced by ischemia-reperfusion. OBJECTIVE: To evaluate the effect of essential amino acid α-keto acid analogs on renal ischemia-reperfusion injury in Wistar rats. MATERIALS AND METHODS: Rats were divided into 11 groups (n=6/group): Two groups received physiological saline with or without ischemia-reperfusion injury (45 min/24 h), six groups received essential amino acid α-keto acid analogs (400, 800, or 1,200 mg/kg/24 h/7d) with or without ischemia-reperfusion injury (essential amino acid α-keto acid analogs + ischemia-reperfusion), and two groups received allopurinol (50 mg/kg/24 h/7d) with or without ischemia-reperfusion injury. Biochemical markers included creatinine and blood urea nitrogen (BUN), proinflammatory cytokines (IL-1ß, IL-6, and TNF-α), renal damage markers (cystatin C, KIM-1, and NGAL), and markers of oxidative stress such as malondialdehyde (MDA) and total antioxidant activity. RESULTS: The essential amino acid α-keto acid analog- and allopurinol-treated groups had lower levels of creatinine, BUN, renal damage markers, proinflammatory cytokines, and MDA than their corresponding ischemia-reperfusion groups. These changes were related to the essential amino acid α-keto acid analogs dosage. Total antioxidant activity was lower in essential amino acid α-keto acid analog- and allopurinol-treated groups than in the corresponding ischemia-reperfusion groups. CONCLUSIONS: This is a new report on the nephroprotective effects of essential amino acid α-keto acid analogs against ischemia-reperfusion injury. Essential amino acid α-keto acid analogs decreased the levels of biochemical markers, kidney injury markers, proinflammatory cytokines, and MDA while minimizing total antioxidant consumption.


Introducción. Los α-cetoanálogos de aminoácidos esenciales se utilizan en el tratamiento de la enfermedad renal crónica para retrasar los síntomas de la uremia. Sin embargo, se desconoce si los α-cetoanálogos de aminoácidos esenciales afectan el estrés oxidativo y la inflamación en la lesión renal aguda tal como en la producida por la isquemia-reperfusión. Objetivo. Evaluar el efecto de las α-cetoanálogos de aminoácidos esenciales sobre la lesión renal por isquemia-reperfusión en ratas Wistar. Materiales y métodos. Se emplearon 11 grupos de ratas (n=6): dos grupos recibieron solución salina fisiológica con lesión isquemia-reperfusión o sin ella (45 min/24 h), seis grupos recibieron α-cetoanálogos de aminoácidos esenciales (400, 800 o 1.200 mg/kg/24 h/7d) con lesión isquemia-reperfusión o sin ella (α-cetoanálogos de aminoácidos esenciales + isquemia-reperfusión), y dos grupos recibieron (50 mg/kg/24 h/7d) con lesión isquemia-reperfusión o sin ella. Los marcadores bioquímicos incluyeron creatinina y nitrógeno ureico en sangre (BUN), citocinas proinflamatorias (IL-1ß, IL-6 y TNF-α), marcadores de daño renal (cistatina C, KIM-1 y NGAL) y marcadores del estrés oxidativo como el malondialdehído (MDA) y la actividad antioxidante total. Resultados. Los grupos tratados con α-cetoanálogos de aminoácidos esenciales y alopurinol tuvieron niveles inferiores de creatinina, BUN, marcadores de daño renal, citocinas proinflamatorias, actividad antioxidante total y MDA que los grupos isquemia-reperfusión correspondientes. Estos cambios se asociaron con la dosis. La actividad antioxidante total fue menor en los grupos tratados con α-cetoanálogos de aminoácidos esenciales que en los grupos isquemia-reperfusión correspondientes. Conclusiones. Este es un nuevo informe de los efectos nefroprotectores de las α-cetoanálogos de aminoácidos esenciales contra la lesión isquemia-reperfusión. Los α-cetoanálogos de aminoácidos esenciales disminuyeron los niveles de los marcadores bioquímicos, de los de lesión renal, de las citocinas proinflamatorias y el MDA, a la vez que minimizaron el consumo total de antioxidantes.


Subject(s)
Amino Acids, Essential/therapeutic use , Antioxidants/therapeutic use , Keto Acids/therapeutic use , Kidney/blood supply , Reperfusion Injury/drug therapy , Allopurinol/therapeutic use , Amino Acids, Essential/administration & dosage , Animals , Antioxidants/analysis , Biomarkers , Blood Urea Nitrogen , Creatinine/blood , Cystatin C/blood , Cytokines/blood , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Keto Acids/administration & dosage , Kidney/pathology , Lipocalin-2/blood , Male , Malondialdehyde/blood , Oxidative Stress/drug effects , Random Allocation , Rats , Rats, Wistar , Reperfusion Injury/blood , Reperfusion Injury/pathology , Reperfusion Injury/prevention & control
6.
Photodiagnosis Photodyn Ther ; 31: 101877, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32534247

ABSTRACT

Photocytotoxic effect induced by 5,10,15,20-tetrakis[4-(3-N,N-dimethylaminopropoxy)phenyl]porphyrin (TAPP) and 5,10,15,20-tetrakis[4-(3-N,N,N-trimethylaminepropoxy)phenyl]porphyrin (TAPP+4) was examined in Candida albicans to obtain information on the mechanism of photodynamic action and cell damage. For this purpose, the photokilling of the yeast was investigated under anoxic conditions and cell suspensions in D2O. Moreover, photoinactivation of C. albicans was evaluated in presence of reactive oxygen species scavengers, such as sodium azide and d-mannitol. The results indicated that singlet molecular oxygen was the main reactive species involved in cell damage. On the other hand, the binding and distribution of these porphyrins in the cells was observed by fluorescence microscopy. Morphological damage was studied by transmission electron microscopy (TEM), indicating modifications in the cell envelopment. Furthermore, deformed cells were observed after photoinactivation of C. albicans by toluidine blue staining. In addition, modifications in the cell envelope due to the photodynamic activity was found by scanning electron microscopy (SEM). Similar photodamage was observed with both porphyrin, which mainly produced alterations in the cell barriers that lead to the photoinactivation of C. albicans.


Subject(s)
Photochemotherapy , Porphyrins , Candida albicans , Photochemotherapy/methods , Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Singlet Oxygen
7.
J Photochem Photobiol B ; 158: 243-51, 2016 May.
Article in English | MEDLINE | ID: mdl-26994333

ABSTRACT

A novel 5,10,15,20-tetrakis[4-(3-N,N-dimethylaminopropoxy)phenyl]chlorin (TAPC) was synthesized by reduction of the corresponding porphyrin TAPP with p-toluenesulfonhydrazide, followed by selective oxidation with o-chloranil. Spectroscopic properties and the photodynamic activity of these photosensitizers were compared in N,N-dimethylformamide. An increase in the absorption band at 650nm was found for the chlorin derivative with respect to TAPP. These photosensitizers emit red fluorescence with quantum yields of 0.15. Both compounds were able to photosensitize singlet molecular oxygen with quantum yields of about 0.5. Also, the formation of superoxide anion radical was detected in the presence of TAPC or TAPP and NADH. Photodynamic inactivation was investigated on a Gram-positive bacterium Staphylococcus aureus, a Gram-negative bacterium Escherichia coli and a fungal yeast Candida albicans cells. In vitro experiments showed that TAPC or TAPP were rapidly bound to microbial cells at short incubation periods. These photosensitizers, without intrinsic positive charges, contain four basic amino groups. These substituents can be protonated at physiological pH, increasing the interaction with the cell envelopment. Photosensitized inactivation improved with an increase of both photosensitizer concentrations and irradiation times. After 15min irradiation, a 7 log reduction of S. aureus was found for treated with 1µM photosensitizer. Similar result was obtained with E. coli after using 5µM photosensitizer and 30min irradiation. Also, the last conditions produced a decrease of 5 log in C. albicans cells. Therefore, TAPC was highly effective as a broad-spectrum antimicrobial photosensitizer.


Subject(s)
Anti-Infective Agents/pharmacology , Photosensitizing Agents/pharmacology , Porphyrins/chemical synthesis , Porphyrins/pharmacology , Magnetic Resonance Spectroscopy , Porphyrins/chemistry , Spectrometry, Fluorescence/methods , Spectrophotometry, Ultraviolet/methods
8.
Arch Microbiol ; 196(11): 803-9, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25085617

ABSTRACT

The Fusarium head blight of grain cereals is a significant disease worldwide. In Argentina, high levels of contamination with Fusarium proliferatum have been found in crops. Many strains of the Pseudomonas genus antagonize the growth of fungi by different mechanisms, such as the production of antibiotics, siderophores, volatiles, and extracellular enzymes. In this work, we have designed a new system for studying the growth inhibition of F. proliferatum-namely by volatile compounds produced by Pseudomonas fluorescens MGR12. In both rich and minimal media, the bacterium released volatiles that negatively affected the mycelial growth of that phytopathogenic fungus. These bacterial compounds were analyzed by gas chromatography-mass spectrometry, but only a few could be identified by comparing their mass spectra with the libraries of the National Institutes of Standards and Technology MS search.


Subject(s)
Antibiosis , Fusarium/growth & development , Pseudomonas fluorescens/chemistry , Pseudomonas fluorescens/metabolism , Fusarium/drug effects , Volatile Organic Compounds/chemistry , Volatile Organic Compounds/isolation & purification , Volatile Organic Compounds/metabolism , Volatile Organic Compounds/pharmacology
9.
Rev. costarric. salud pública ; 23(1): 8-12, ene.-jun. 2014. tab
Article in Spanish | LILACS | ID: lil-729698

ABSTRACT

El cáncer cervicouterino es en el mundo y en Costa Rica una de las 3 primeras causas de cáncer en las mujeres. La detección temprana de lesiones premalignas o malignas mejora el pronóstico de las usuarias. Objetivo: Encontrar si hay factores asociados a las alteraciones de la citología vaginal en un área de salud urbana de Costa Rica durante 2009. Metodología: Estudio de casos y controles en usuarias de una área de salud urbana de Costa Rica durante 2009. Se definió caso como toda mujer residente de esa área que presentara una citología vaginal alterada, displasia leve, moderada, severa o carcinoma durante 2009. Los controles se seleccionaron de forma aleatoria simple, tomando como marco muestral el registro de mujeres que se habían realizado citologías vaginales durante el 2009 en esa área. La recolección de la información se hizo a través de un cuestionario. Se calcularon medidas de frecuencia, de tendencia central y dispersión, OR, IC 95 %. Resultados: Se incluyeron 62 casos y 137 controles. La edad promedio de los casos fue 43 años (DE±17). El ASCUS fue la lesión más frecuente 39 % (IC 95 %=22,43-51,93). Los factores asociados a la aparición de lesiones fueron tabaco (OR=2.35; IC 95 %=1,26-4,31), inicio de actividad sexual antes de 18 años (OR=2;I C 95 %=1,06-3,64) y haber tenido 3 o más compañeros sexuales (OR=2, 10;IC 95 % 1,11-3,97). Discusión: Se encontró similitud entre lo descrito en la literatura y lo hallado en este estudio. Se recomendó dar a conocer este estudio a las mujeres de esa área de salud, ya que los factores encontrados son modificables y además se planteó a la dirección del área realizar campañas de promoción y prevención que fomenten conductas sexuales sanas.


Cervical cancer is among the leading causes of cancer in women globally; in Costa Rica it is among the top three causes. Although the PAP smears is part of the guidelines of care for women, the coverage in some areas of health is low. Objective: Identify demographic and clinical factors associated with abnormal Pap test results Methods: We conducted a health center-based case-control study. A case was defined as any woman seeking care in a health center during 2009, having a Pap test positive for either cells of undetermined significance (Atypical Squamous Cells of Undetermined Significance) mild, moderate or severe dysplasia. Controls were selected by simple random sampling using records of women seen at the same health centers in 2009 and having normal PAP smears. Odds ratios and 95 % confidence intervals (95% CI) were calculated for associations between potential risk factors and abnormal PAP smears. Results: We identified 62 cases and 137 controls. The average age of cases was 43 was not significantly different from that of controls (Student t p = 0,90). ASCUS was the most frequent cause of abnormal cytology (39 %). Factors found to be significantly associated with abnormal cytology were: tobacco use (OR=2,35; 95 % CI=1,26-4,31), onset of sexual activity before age 18 (OR=2,0; 95 % CI=1,06-3,64) and having a history of > 3 sexual partners (OR=2,0; 95 % CI=1,11-3,97). Conclusions: There was similarity between risk factors we identified as described in the literature, like onset of sexual activity before age 18 and have history of 3 or more sexual parthers. These are common risk factors associated with HPV infection. Our study was limited by the failure to follow-up colposcopy results for definitive diagnoses and no HPV test. Considering these risk factors represent modifiable health behaviors, we recommended dissemination of our findings to local health authorities in order to generate intervention strategies to promote responsible, healthy sexual behaviors as how to reduce tobacco consumption and develop healthy sexual habits.


Subject(s)
Humans , Female , Carcinoma , Uterine Cervical Dysplasia , Uterine Cervical Neoplasms , Costa Rica , Papanicolaou Test
10.
Syst Appl Microbiol ; 35(5): 342-51, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22748594

ABSTRACT

Pseudomonas strains producing antimicrobial secondary metabolites play an important role in the biocontrol of phytopathogenic fungi. In this study, native Pseudomonas spp. isolates were obtained from the rhizosphere, endorhizosphere and bulk soil of maize fields in Córdoba (Argentina) during both the vegetative and reproductive stages of plant growth. However, the diversity based on repetitive-element PCR (rep-PCR) and amplified ribosomal DNA restriction analysis (ARDRA) fingerprinting was not associated with the stage of plant growth. Moreover, the antagonistic activity of the native isolates against phytopathogenic fungi was evaluated in vitro. Several strains inhibited members of the genera Fusarium, Sclerotinia or Sclerotium and this antagonism was related to their ability to produce secondary metabolites. A phylogenetic analysis based on rpoB or 16S rRNA gene sequences confirmed that the isolates DGR22, MGR4 and MGR39 with high biocontrol potential belonged to the genus Pseudomonas. Some native strains of Pseudomonas were also able to synthesise indole acetic acid and to solubilise phosphate, thus possessing potential plant growth-promoting (PGPR) traits, in addition to their antifungal activity. It was possible to establish a relationship between PGPR or biocontrol activity and the phylogeny of the strains. The study allowed the creation of a local collection of indigenous Pseudomonas which could be applied in agriculture to minimise the utilisation of chemical pesticides and fertilisers.


Subject(s)
Fungi/drug effects , Pseudomonas/chemistry , Pseudomonas/genetics , Zea mays/microbiology , Algorithms , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Argentina , Cluster Analysis , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Genetic Variation , Microbial Interactions , Phylogeny , Plant Growth Regulators , Pseudomonas/classification , Pseudomonas/isolation & purification , Pyrrolnitrin/isolation & purification , Pyrrolnitrin/pharmacology , Sequence Analysis, DNA
11.
Microbiology (Reading) ; 158(Pt 6): 1493-1503, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22442306

ABSTRACT

R-type and F-type pyocins are high-molecular-mass bacteriocins produced by Pseudomonas aeruginosa that resemble bacteriophage tails. They contain no head structures and no DNA, and are used as defence systems. In this report, we show that Pseudomonas fluorescens SF4c, a strain isolated from the wheat rhizosphere, produces a high-molecular-mass bacteriocin which inhibits the growth of closely related bacteria. A mutant deficient in production of this antimicrobial compound was obtained by transposon mutagenesis. Sequence analysis revealed that the transposon had disrupted a gene that we have named ptm, since it is homologous to that encoding phage tape-measure protein in P. fluorescens Pf0-1, a gene belonging to a prophage similar to phage-like pyocin from P. aeruginosa PAO1. In addition, we have identified genes from the SF4c pyocin cluster that encode a lytic system and regulatory genes. We constructed a non-polar ptm mutant of P. fluorescens SF4c. Heterologous complementation of this mutation restored the production of bacteriocin. Real-time PCR was used to analyse the expression of pyocin under different stress conditions. Bacteriocin was upregulated by mitomycin C, UV light and hydrogen peroxide, and was downregulated by saline stress. This report constitutes, to our knowledge, the first genetic characterization of a phage tail-like bacteriocin in a rhizosphere Pseudomonas strain.


Subject(s)
Anti-Bacterial Agents/metabolism , Pseudomonas fluorescens/metabolism , Pyocins/metabolism , Rhizosphere , Triticum/microbiology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Bacteriophages/chemistry , Bacteriophages/metabolism , Molecular Sequence Data , Molecular Weight , Pseudomonas fluorescens/chemistry , Pseudomonas fluorescens/genetics , Pseudomonas fluorescens/isolation & purification , Pyocins/chemistry , Pyocins/isolation & purification , Pyocins/pharmacology , Soil Microbiology , Triticum/growth & development
12.
Autoimmunity ; 44(7): 543-8, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21875376

ABSTRACT

The revised score of the International Autoimmune Hepatitis Group (R-IAIHG) and the simplified criteria (SC) are used for diagnosis of autoimmune hepatitis (AIH). Our aim is to evaluate the performance of these classifications to differentiate AIH from other autoimmune liver diseases. The frequency of diagnosis of definite AIH was similar both by the R-IAIHG and the SC systems (41% versus 40%), whereas diagnosis of probable AIH was made more commonly by the R-IAIHG than the SC (59% versus 29%), and 23 patients that have been graded as definite (n = 7) or probable (n = 16) AIH by the R-IAIHG had non-diagnostic scores by the SC system. The scoring systems rendered concordant diagnosis of definite (n = 15) and probable (n = 13) AIH in 28/73 patients (38%). Discordant diagnoses of AIH were rendered in 45/73 patients (62%). The R-IAIHG exhibited a sensitivity of 95%, specificity of 90%, and positive predictive value (PPV) and negative predictive value (NPV) of 93% for both. On the other hand, the SC had a lower sensitivity (65%) but a higher specificity (100%), PPV of 100%, and NPV of 68%. In conclusion, both international scoring systems diagnosed the same number of cases as definite AIH. The R-IAIHG showed a higher sensitivity in diagnosing AIH, whereas the SC showed a higher specificity. SC are easier to apply at the bedside and exclude more patients that could have a different etiology.


Subject(s)
Classification/methods , Hepatitis, Autoimmune/diagnosis , Adolescent , Adult , Aged , Child , Child, Preschool , Cohort Studies , Female , Hepatitis, Autoimmune/classification , Hepatitis, Autoimmune/immunology , Hispanic or Latino , Humans , Male , Mexico , Middle Aged , Predictive Value of Tests , ROC Curve , Retrospective Studies , Sensitivity and Specificity , Young Adult
13.
Liver Int ; 30(5): 772; author reply 772-3, 2010 May.
Article in English | MEDLINE | ID: mdl-19968779
14.
Antonie Van Leeuwenhoek ; 97(3): 241-51, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20020326

ABSTRACT

Survival of Pseudomonas sp. SF4c and Pseudomonas sp. SF10b (two plant-growth-promoting bacteria isolated from wheat rhizosphere) was investigated in microcosms. Spontaneous rifampicin-resistant mutants derived from these strains (showing both growth rate and viability comparable to the wild-strains) were used to monitor the strains in bulk soil and wheat rhizosphere. Studies were carried out for 60 days in pots containing non-sterile fertilized or non-fertilized soil. The number of viable cells of both mutant strains declined during the first days but then became established in the wheat rhizosphere at an appropriate cell density in both kinds of soil. Survival of the strains was better in the rhizosphere than in the bulk soil. Finally, the antagonism of Pseudomonas spp. against phytopatogenic fungi was evaluated in vitro. Both strains inhibited the mycelial growth (or the resistance structures) of some of the phytopathogenic fungi tested, though variation in this antagonism was observed in different media. This inhibition could be due to the production of extracellular enzymes, hydrogen cyanide or siderophores, signifying that these microorganisms might be applied in agriculture to minimize the utilization of chemical pesticides and fertilizers.


Subject(s)
Microbial Viability , Plant Roots/microbiology , Pseudomonas/physiology , Soil Microbiology , Triticum/microbiology , Animals , Antibiosis , Antifungal Agents/metabolism , Cluster Analysis , Colony Count, Microbial , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fungi/growth & development , Molecular Sequence Data , Phylogeny , Plant Growth Regulators/metabolism , Pseudomonas/classification , Pseudomonas/growth & development , Pseudomonas/metabolism , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
15.
Ann Hepatol ; 8(3): 207-11, 2009.
Article in English | MEDLINE | ID: mdl-19841499

ABSTRACT

INTRODUCTION: Type 1 hepatorenal syndrome (HRS) is a functional renal failure that complicates end-stage cirrhosis. The vasopressin analogue terlipressin has been associated with improved renal function in patients with type 1 HRS. AIM: To evaluate the effectiveness of an infusion of terlipressin plus albumin in reversing type 1 HRS, its tolerability, and its adverse effects. METHODS: Thirteen consecutive patients with cirrhosis and type 1 HRS were included in the study. All patients received terlipressin plus albumin as treatment for HRS. The patients were divided in two groups. Group 1 contained eight patients in whom HRS was reversed with treatment, who were classified as responders. Group 2 contained five patients who were nonresponders. RESULTS: Sixty-one percent of the patients who received terlipressin plus albumin responded to therapy and underwent HRS reversal. In two patients, treatment with terlipressin was stopped because of adverse events. No relapse of HRS after terlipressin withdrawal was observed in this study. CONCLUSION: The rate of successful treatment with terlipressin plus albumin was 61%, similar to that in previously reported controlled trials. However, this is the first experience reported in Mexico. A cardiovascular evaluation is required before the start of treatment with terlipressin. This treatment appears to be an effective therapy for improving renal function in patients with type 1 HRS.


Subject(s)
Albumins/therapeutic use , Hepatorenal Syndrome/drug therapy , Hepatorenal Syndrome/etiology , Liver Cirrhosis/complications , Lypressin/analogs & derivatives , Creatinine/blood , Drug Therapy, Combination , Female , Hepatorenal Syndrome/epidemiology , Humans , Lypressin/therapeutic use , Male , Mexico , Middle Aged , Pilot Projects , Prospective Studies , Terlipressin , Treatment Outcome , Vasoconstrictor Agents/therapeutic use
16.
Ann Hepatol ; 8(2): 123-8, 2009.
Article in English | MEDLINE | ID: mdl-19502655

ABSTRACT

INTRODUCTION: Leptin has been implicated in the pathogenesis of nonalcoholic steatohepatitis. It has also been suggested that adiponectin plays an important role in the transition from fatty liver disease to nonalcoholic steatohepatitis. OBJECTIVE: To evaluate whether leptin and adiponectin levels are related to the degree of necroinflammatory activity and fibrosis in patients with nonalcoholic steatohepatitis. METHODS: Leptin and adiponectin levels were determined in 52 patients with nonalcoholic steatohepatitis and in 49 controls by enzyme-linked immunosorbent analysis. RESULTS: Median (interquartile range) leptin levels were higher in patients with nonalcoholic steatohepatitis than in the controls (5.75 (12.3) ng mL-1 and 2.80 (2.40) ng mL-1, respectively; P = 0.0035). Adiponectin levels were lower in patients with nonalcoholic steatohepatitis than in the controls (6.55 (5.05) mg mL-1 and 9.30 (6.70) mg mL-1, respectively; P = 0.0218). Leptin levels were lower in overweight patients than in obese patients (2.25 (6.73) and 8.0 (16.0) ng mL-1, respectively; P = 0.0025). The amount of necroinflammatory activity observed in liver biopsies correlated positively with the amount of fibrosis (P < 0.0001). Increased lactate dehydrogenase correlated with increased fibrosis in patients with nonalcoholic steatohepatitis (P = 0.0012). Necroinflammatory activity correlated with adiponectin, g-glutamyltranspeptidase, the quantitative insulin-sensitivity check index, and ferritin (P < 0.05). Risk factors for nonalcoholic steatohepatitis in the logistic regression analysis were leptin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and g-glutamyltranspeptidase (P < 0.0001). Only lactate dehydrogenase (P = 0.0012) was significantly associated with advanced fibrosis on logistic regression analysis. CONCLUSIONS: Lactate dehydrogenase was associated with fibrosis and advanced fibrosis. Leptin was associated with nonalcoholic steatohepatitis but not with fibrosis or necroinflammatory activity. Adiponectin was related to necroinflammatory activity. Risk factors for nonalcoholic steatohepatitis were leptin and liver enzymes (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and gama-glutamyltranspeptidase).


Subject(s)
Fatty Liver/blood , Leptin/blood , Adiponectin/blood , Adult , Aged , Aged, 80 and over , Alanine Transaminase/blood , Alkaline Phosphatase/blood , Aspartate Aminotransferases/blood , Biomarkers/blood , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Fatty Liver/etiology , Fatty Liver/pathology , Female , Humans , L-Lactate Dehydrogenase/blood , Liver Cirrhosis/blood , Liver Cirrhosis/etiology , Logistic Models , Male , Mexico , Middle Aged , Necrosis , Obesity/blood , Obesity/complications , Overweight/blood , Overweight/complications , Risk Assessment , Risk Factors , Young Adult , gamma-Glutamyltransferase/blood
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