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1.
Rev Gastroenterol Mex (Engl Ed) ; 88(1): 50-56, 2023.
Article in English | MEDLINE | ID: mdl-34863643

ABSTRACT

INTRODUCTION: Methane (CH4) is an inert gas produced by colonic anaerobes and has been associated with different intestinal diseases, including irritable bowel syndrome (IBS). According to geographic region, the prevalence of methanogens varies, being higher in Africa (80%) and lower in the United States (35-40%). In Mexico, the prevalence of methanogens is unknown. AIM: To evaluate the prevalence of CH4 producers and associated factors in a group of patients with IBS and controls in a Mexican population. MATERIALS AND METHODS: A baseline fasting measurement of alveolar H2 and CH4 gas was carried out, by gas chromatography (stationary phase), in consecutive patients diagnosed with IBS and a control group. Subjects with baseline levels of H2 of 0 ppm and CH4 ≥ 5 ppm were classified as methanogenic. RESULTS: A total of 132 controls (53.8% women) and 67 patients with IBS (76% women) were included. The overall prevalence (n = 199) of methanogenic subjects was 38% (n = 76) (95% CI: 0.31-0.45) and they had a greater prevalence of overweight/obesity (56.5 vs 39.8%, P = .028). The prevalence of methanogens in the healthy controls was 41.6% (95% CI: 0.33-0.49), whereas, in the patients with IBS, it was 31.4% (n = 21, 71% IBS-C and 29% IBS-M). CONCLUSIONS: The prevalence of methanogens in our study on a Mexican population was comparable to that reported in other populations and was associated with overweight/obesity. One-third of the patients with IBS presented with methanogens. Said microorganisms were particularlyassociated with the constipation-predominant IBS subtype.


Subject(s)
Irritable Bowel Syndrome , Humans , Female , Male , Irritable Bowel Syndrome/epidemiology , Prevalence , Mexico/epidemiology , Overweight , Obesity
2.
Sci Rep ; 10(1): 8555, 2020 May 22.
Article in English | MEDLINE | ID: mdl-32444609

ABSTRACT

We present a spectroscopic ellipsometry study of Mo-doped VO2 thin films deposited on silicon substrates for the mid-infrared range. The dielectric functions and conductivity were extracted from analytical fittings of Ψ and Δ ellipsometric angles showing a strong dependence on the dopant concentration and the temperature. Insulator-to-metal transition (IMT) temperature is found to decrease linearly with increasing doping level. A correction to the classical Drude model (termed Drude-Smith) has been shown to provide excellent fits to the experimental measurements of dielectric constants of doped/undoped films and the extracted parameters offer an adequate explanation for the IMT based on the carriers backscattering across the percolation transition. The smoother IMT observed in the hysteresis loops as the doping concentration is increased, is explained by charge density accumulation, which we quantify through the integral of optical conductivity. In addition, we describe the physics behind a localized Fano resonance that has not yet been demonstrated and explained in the literature for doped/undoped VO2 films.

3.
Rev Gastroenterol Mex (Engl Ed) ; 85(1): 48-55, 2020.
Article in English, Spanish | MEDLINE | ID: mdl-31104856

ABSTRACT

INTRODUCTION/AIM: Levo-pantoprazole, the S-enantiomer of pantoprazole, is a proton pump inhibitor that has been shown in animal studies to be faster and stronger than its racemic formulation. There are no studies on humans and therefore our aim was to evaluate the effects of levo-pantoprazole versus racemic pantoprazole on intragastric pH. MATERIALS AND METHODS: A randomized controlled study was conducted on patients with erosive gastroesophageal reflux disease that were given 20mg of levo-pantoprazole (n = 15) versus 40mg of racemic pantoprazole (n = 15) for 7 days. Baseline and end-of-treatment symptom evaluation and intragastric pH measurement were carried out. RESULTS: There were no differences between the groups in the baseline evaluations. From 40 to 115min after the first dose of levo-pantoprazole, the mean intragastric pH was higher, compared with that of racemic pantoprazole (p < 0.05). After one week, levo-pantoprazole and racemic pantoprazole significantly reduced intragastric acid production and its esophageal exposure (p < 0.05). Even though there was no statistically significant difference, a larger number of patients that received levo-pantoprazole stated that their heartburn improved within the first 3 days. CONCLUSIONS: The S-enantiomer of pantoprazole (levo-pantoprazole) had a faster and stronger effect with respect to acid suppression, compared with its racemic formulation. Although the effect on symptoms was faster with levo-pantoprazole, occurring within the first days of treatment, it was equivalent to that of the racemate at one week of treatment.


Subject(s)
Gastroesophageal Reflux/drug therapy , Hydrogen-Ion Concentration/drug effects , Pantoprazole/chemistry , Pantoprazole/pharmacology , Proton Pump Inhibitors/chemistry , Proton Pump Inhibitors/pharmacology , Adult , Female , Gastroesophageal Reflux/physiopathology , Humans , Male , Middle Aged , Pantoprazole/therapeutic use , Proton Pump Inhibitors/therapeutic use , Time Factors , Treatment Outcome
4.
Acta Ortop Mex ; 33(1): 42-45, 2019.
Article in Spanish | MEDLINE | ID: mdl-31480126

ABSTRACT

BACKGROUND: The Bruns Garland syndrome (diabetic amyotrophy) it is a very rare condition, with few cases reported in the literature. Clinical differentiation of diabetic amyotrophy or cauda equine syndrome may be difficult. The issue of misdiagnosis has been discussed as a reason for poor outcome after lumbar spine surgery. We report a case of diabetic amyotrophy that mimics a cauda equina syndrome. CASE DESCRIPTION: A 59 years old man diabetic patient that suddenly begins with weakness of lower extremities and loss of sphincters control. The patient was seen in the emergency room, the anteroposterior and lateral radiographs of the lumbosacral spine evidenced spondylolisthesis L5-S1 level II of Meyerding. However, the MRI show no vertebral canal compression, nerve root compression or disc extrusion. Electrodiagnostic study revealed diabetic amyotrophy (Bruns Garland syndrome). The patient rapidly improves with treatment based in antineuritics, diabetes control, physical therapy and rehabilitation. Four months after the diagnosis he recover his muscle strength, has no alterations in the march, no loss of balance, his sensitive is preserved and has no pain. CONCLUSION: Electrodiagnostic and radiologic studies should be used in every diabetic patient presenting with leg pain and/or weakness to differentiate diabetic neuropathy from cauda equina syndrome. Treatment of both diseases may be needed for relief of the patients pain.


ANTECEDENTES: El síndrome de Bruns Garland (amiotrofia diabética) es una condición con pocos casos reportados en la literatura. La diferenciación clínica de una amiotrofia diabética o un síndrome de cauda equina puede ser difícil. El problema de un mal diagnóstico ha sido discutido como una razón para un mal resultado después de una cirugía de la columna lumbar. Se presenta un caso de amiotrofia diabética que imita un síndrome de cauda equina. DESCRIPCIÓN DEL CASO: Masculino de 59 años de edad con diabetes, comienza repentinamente con debilidad en las extremidades inferiores y pérdida del control de los esfínteres. Este paciente fue atendido en la sala de urgencias, las radiografías anteroposterior y lateral de la columna lumbosacra evidenciaron espondilolistesis L5-S1 nivel II de Meyerding. Sin embargo, la IRM no mostró ninguna compresión del canal vertebral, compresión de la raíz nerviosa, ni extrusión del disco. El estudio de electrodiagnóstico reveló amiotrofia diabética (síndrome de Bruns Garland). El paciente rápidamente mejoró con el tratamiento basado en antineuríticos, control diabético, terapia física y rehabilitación. Cuatro meses después del diagnóstico, el paciente recuperó su fuerza muscular, no mostró alteraciones en la marcha, ni pérdida del equilibrio, su sensibilidad se conserva y no manifiesta dolor. DISCUSIÓN: Deberán utilizarse estudios de electrodiagnóstico y radiológicos en todo paciente diabético que presente dolor en la pierna y/o debilidad para diferenciar una neuropatía diabética de un síndrome de cauda equina. El tratamiento en ambas enfermedades puede ser necesario para aliviar el dolor del paciente.


Subject(s)
Cauda Equina Syndrome , Cauda Equina , Cauda Equina Syndrome/diagnosis , Diagnosis, Differential , Humans , Lumbar Vertebrae , Magnetic Resonance Imaging , Male , Middle Aged
5.
BMC Psychiatry ; 19(1): 78, 2019 02 21.
Article in English | MEDLINE | ID: mdl-30791883

ABSTRACT

BACKGROUND: Polypharmacy increases the risk of pharmacological interactions, prevalence of secondary effects and with this the lack of adherence to treatment. It is estimated that between 10 and 40% of patients hospitalized in psychiatric institutions are prescribed more than one antipsychotic. The objective of the present study was to identify the prevalence of polypharmacy, evaluate adverse effects associated to the use of psych drugs and to estimate the risk in specific groups. METHODS: We carried out a longitudinal, retrospective study that included the analysis of all discharged patients (n = 140) in the first trimester of the year in a psychiatric hospital in Mexico. The information was classified into 7 sections: sociodemographic, diagnosis, clinical follow-up information, prescribed drugs, adverse reactions, substance abuse, laboratory and complementary results. Risk estimation was obtained with Odds Ratios, to correlate continuous variables Pearson's correlation was used. Student's T and Mann Whitney's U were used to compare 2 independent samples; multiple and linear regressions were carried out. RESULTS: The mean number of drugs used during hospitalization was 7.8 drugs per patient. The mean prescribed psych drugs was 4.07. The mean antipsychotic dose was the risperidone equivalent of 5.08 mg. 29.2% of patients had at least one secondary effect associated to the use of drugs, 17.8% presented extrapyramidal symptoms. 81.4% of patients were prescribed 6 or more drugs (polypharmacy) and were 5 times more likely to suffer a secondary effects (OR 6.24). 14.2% had polypharmacy while receiving antipsychotics and had more than twice the risk of presenting extrapyramidal symptoms (OR 3.05). For each added psych drug, hospital stay increased by 6.56 days. CONCLUSIONS: Despite international guideline recommendations where reasoned and conciliatory prescription of psych drugs is advised, there is still a high prevalence of polypharmacy in patients hospitalized in psychiatric institutions. In the present study 4 out of 5 patients received polypharmacy decreasing tolerability, treatment adherence and increasing the risk and costs secondary to an increased hospital stay.


Subject(s)
Antipsychotic Agents/therapeutic use , Mental Disorders/drug therapy , Polypharmacy , Adult , Drug Therapy, Combination , Drug-Related Side Effects and Adverse Reactions , Female , Hospitalization/statistics & numerical data , Hospitals, Psychiatric , Humans , Longitudinal Studies , Male , Mexico , Middle Aged , Patient Discharge/statistics & numerical data , Prevalence , Retrospective Studies
6.
Neotrop Entomol ; 48(1): 121-125, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30136041

ABSTRACT

Vindex chimalapensis Ariza-Marín, Reyes-Castillo, Moctezuma & Sánchez-Huerta, a new species, is described from the cloud forest in Oaxaca, México. Vindex chimalapensis is like V. sculptilis Bates in the form of lateral elytral punctures and glabrous epipleura, but has dorsal punctures in the pronotum and the form of the aedeagus differs on the basal piece. Male genitalia, female genitalia, and head are shown in photographs. Vindex chimalapensis is the only species known from this genus with dorsal punctures on the pronotum. Ecology, distribution, and biogeography of Vindex and the Mountain Mesoamerican distribution pattern are discussed, with emphasis on V. chimalapensis.


Subject(s)
Coleoptera/anatomy & histology , Coleoptera/classification , Animal Distribution , Animals , Female , Genitalia, Female/anatomy & histology , Genitalia, Male/anatomy & histology , Male , Mexico
7.
Sci Total Environ ; 652: 1102-1112, 2019 Feb 20.
Article in English | MEDLINE | ID: mdl-30586797

ABSTRACT

Estuaries are highly productive ecosystems, defined by salt-freshwater exchanges that are significantly altered by changes upstream and in adjacent coastal areas. Tropical estuaries are characterized by the periodic advance and retreat of saline intrusion, depending on seasonality, episodic river flows and flooding events. Salt-water intrusion due to the estuarine dynamics might be affected by dam systems, which could modify the hydrological regime of the estuary in relation to other stressors, such as land use changes. For this purpose, field measurements of salinity, temperature, river-discharge and flow velocities were conducted over a year to analyze the current hydrological regime in the upper estuary of the Grijalva River in the southern Gulf of Mexico, part of the Biosphere Reserve "Pantanos de Centla", one of the most biodiverse areas in the world. Analysis of land use and vegetation cover was performed. Historical implications of the hydrological performance of the four-dam system (1957 to 2014) are presented, together with the upstream-induced changes (i.e. discharge and seasonal water volumes variations): before, between and after the full operation of the dam system. A general loss of seasonality in the river discharge was identified (1974-1987), when critical mean annual water discharges were registered (Qmean from 263.56 to 126.49 m3/s). Chronological changes in the estuary and in the surrounding area due to the introduction of large extensions of cultivated grassland (~1020 km2), reduction in mangrove cover (~223 km2) and tular (~1340 km2) were noticed. These modifications mostly occurred before conservation strategies were implemented, such as the designation of the Biosphere Reserve (1992). This study contributes to a better understanding of the response of estuarine systems to anthropic perturbations and the development of long-term management plans that could take into account climate change and the increase of hydropower development.

8.
Rev Gastroenterol Mex (Engl Ed) ; 83(3): 253-258, 2018.
Article in English, Spanish | MEDLINE | ID: mdl-29456091

ABSTRACT

INTRODUCTION AND AIM: Cancer is the result of the interaction of genetic and environmental factors. It has recently been related to viral infections, one of which is human papillomavirus. The aim of the present study was to describe the frequency of human papillomavirus infection in patients with digestive system cancers. MATERIALS AND METHODS: A prospective, multicenter, observational study was conducted on patients with gastrointestinal cancer at 2public healthcare institutes in Veracruz. Two tumor samples were taken, one for histologic study and the other for DNA determination of human papillomavirus and its genotypes. Anthropometric variables, risk factors, sexual habits, tumor location, and histologic type of the cancer were analyzed. Absolute and relative frequencies were determined using the SPSS version 24.0 program. RESULTS: Fifty-three patients were studied. They had gastrointestinal cancer located in: the colon (62.26%), stomach (18.87%), esophagus (7.55%), rectum (7.55%), and small bowel (3.77%). Human papillomavirus was identified in 11.32% of the patients, 66.7% of which corresponded to squamous cell carcinoma and 33.3% to adenocarcinoma. Only genotype 18 was identified. Mean patient age was 61.8±15.2 years, 56.60% of the patients were men, and 43.40% were women. A total of 15.8% of the patients had a family history of cancer and 31.6% had a personal history of the disease, 38.6% were tobacco smokers, and 61.4% consumed alcohol. Regarding sex, 5.3% of the patients said they were homosexual, 3.5% were bisexual, 29.8% engaged in oral sex, and 24.6% in anal sex. CONCLUSIONS: Our study showed that human papillomavirus infection was a risk factor for the development of gastrointestinal cancer, especially of squamous cell origin.


Subject(s)
Gastrointestinal Neoplasms/epidemiology , Papillomavirus Infections/epidemiology , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/epidemiology , Female , Gastrointestinal Neoplasms/complications , Humans , Male , Mexico/epidemiology , Middle Aged , Papillomaviridae , Papillomavirus Infections/complications , Prospective Studies , Risk Factors , Sexual Behavior
9.
Ginecol Obstet Mex ; 84(1): 14-8, 2016 Jan.
Article in Spanish | MEDLINE | ID: mdl-27290842

ABSTRACT

OBJECTIVE: To determine the prevalence of Chlamydia, Ureaplasma and Mycoplasma in patients with peritoneal tubal factor infertility and altered. MATERIAL AND METHODS: A descriptive, observational, retrospec- tive, transversal, infertility patients Juarez Hospital of Mexico 2013 to 2015. Study included patients with infertility diagnosis and detection of antibodies (IgG) by ELISA for Chlamydia and vaginal cultures for Mycoplasma and Ureaplasma, hysterosalpingography and histerolapa- roscopia with chromotubation RESULTS: 46 patients with a mean age of 32.5 years. It was found that 36% were positive for these infections (n = 17): Chlamydia in 8.7% (n = 4), Ureaplasma in 21.7% (n = 10) and Mycoplasma in 6.5% (n = 3). Chlamydia patients and bilateral tubal occlusion (OTB) in 5.8% (n = 1), Ureaplasma and OTB (n = 5) were identified in 29.4% of them with pelvic inflammatory disease (PID) and tubal obstruction Ureaplasma right (OTD) in 5.8% (n = 1), Ureaplasma and tubal patency but with loose adhesions in 5.8% (n = 1) and Mycoplasma with OTB in 11.1% (n = 2), p = 0.425. Hysterosalpingography showed a sensitivity of 59% and specificity of 79%. CONCLUSIONS: Although there was no association of variables, Ureaplasma infection was more common in patients with infertility and tubal damage.


Subject(s)
Chlamydia Infections/epidemiology , Fallopian Tube Diseases/complications , Mycoplasma Infections/epidemiology , Ureaplasma Infections/epidemiology , Adult , Chlamydia Infections/complications , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Fallopian Tube Diseases/epidemiology , Female , Humans , Hysterosalpingography , Infertility, Female/etiology , Infertility, Female/microbiology , Mexico/epidemiology , Mycoplasma Infections/complications , Prevalence , Retrospective Studies , Sensitivity and Specificity , Ureaplasma Infections/complications , Young Adult
10.
J Phys Condens Matter ; 26(2): 026001, 2014 Jan 15.
Article in English | MEDLINE | ID: mdl-24304620

ABSTRACT

The dipolar interaction field in arrays of nickel nanotubes has been investigated on the basis of expressions derived from the effective demagnetizing field of the assembly as well as magnetometry measurements. The model incorporates explicitly the wall thickness and aspect ratio, as well as the spatial order of the nanotubes. The model and experiment show that the interaction field in nanotubes is smaller than that in solid nanowires due to the packing fraction reduction in tubes related to their inner cavity. Finally, good agreement between the model and experiment is found for the variation of the interaction field as a function of the tube wall thickness.

11.
J Phys Condens Matter ; 25(22): 226003, 2013 Jun 05.
Article in English | MEDLINE | ID: mdl-23673456

ABSTRACT

A mean field model is presented for the configuration dependent effective demagnetizing and anisotropy fields in assemblies of exchange decoupled magnetic particles of arbitrary shape which are expressed in terms of the demagnetizing factors of the particles and the volumetric shape containing the assembly. Perpendicularly magnetized two-dimensional (2D) assemblies have been considered, for which it is shown that the demagnetizing field is lower than the continuous thin film. As an example of these 2D systems, arrays of bistable cylindrical nanowires have been characterized by remanence curves as well as ferromagnetic resonance, serving to show the correspondence of these measurements with the model and also to validate the mean field approach. Linear chains of cylinders and spheres have been analyzed, leading to simple expressions to describe the easy axis rotation induced by the interaction field in chains of low aspect ratio cylindrical particles, and the dipolar magnetic anisotropy observed in the linear chain of spheres. These examples serve to underline the dependence on the dipolar interaction field and effective demagnetizing factor of the contributions that arise from the shape of the outer volume.

12.
Occup Med (Lond) ; 61(4): 265-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21515666

ABSTRACT

BACKGROUND: Raw meat may contain viable Toxoplasma gondii tissue cysts and therefore handling of raw meat may represent a risk for T. gondii infection. AIMS: To determine the association of T. gondii infection with occupational exposure to raw meat. METHODS: Case-control seroprevalence study design with enzyme-linked immunoassays for the presence and levels of anti-Toxoplasma IgG antibodies and for the presence of anti-Toxoplasma IgM antibodies. Those occupationally exposed to raw meat consisted of butchers working in two abattoirs and 35 butcher's shops in Durango, Mexico. The control group consisted of individuals from the general population from the same region. Socio-demographic, work, clinical and behavioural characteristics from each butcher were obtained. RESULTS: One hundred and twenty-four workers occupationally exposed to raw meat and 248 control subjects were examined. Eight (7%) of the butchers and 22 (9%) of the controls were positive for anti-T. gondii IgG antibodies [not statistically significant (NS)]. Anti-T. gondii IgG levels were >150 IU/ml in 7 (6%) butchers and 14 (6%) controls (NS). Anti-T. gondii IgM antibodies were found in five (4%) of the butchers and four (2%) of the controls (NS). None of the factors examined appeared to predict seropositivity although both butchers who reported consuming dried beef were seropositive compared to 6/122 controls (95% CI 0.60-1.29). CONCLUSIONS: Occupational exposure to raw meat was not associated with seropositivity for T. gondii infection. Consumption of dried beef may warrant further investigation.


Subject(s)
Abattoirs , Food-Processing Industry , Meat/parasitology , Occupational Diseases/epidemiology , Occupational Exposure/adverse effects , Toxoplasmosis/epidemiology , Adolescent , Adult , Aged , Animals , Antibodies, Protozoan/blood , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Mexico/epidemiology , Middle Aged , Multivariate Analysis , Prevalence , Seroepidemiologic Studies , Young Adult
13.
Acta Ortop Mex ; 25(4): 216-22, 2011.
Article in Spanish | MEDLINE | ID: mdl-22509643

ABSTRACT

Venous thromboembolic disease (VTED) is a public health problem worldwide. In the United States it causes 2 million annual cases. Its annual incidence is 1-2 cases per 1,000 individuals in the general population. It is a disease frequently associated with life threatening complications and its mortality rate is 1-5% of cases. Due to its high complication rate, its slow recovery, and the need for prolonged disability, it is considered as a high-cost disease. VTED may occur in both surgical and medical patients; the known associated risk factors include prolonged rest, active cancer, congestive heart failure, atrial fibrillation, and stroke, among the major medical conditions. Orthopedic surgery represents the main surgical risk factor for VTED, including mainly hip and knee replacements, as well as polytraumatized patients with severe spinal lesions, and major fractures. VTED may be prevented with the appropriate use of antithrombotics. The participants in this consensus defined thromboprophylaxis as the strategy and actions undertaken to reduce the risk of VTED in patients undergoing high risk orthopedic surgery. The position of the Mexican College of Orthopedics and Traumatology regarding the prevention of VTED in orthopedic surgery is described herein.


Subject(s)
Venous Thromboembolism/prevention & control , Humans , Orthopedic Procedures/adverse effects , Risk Factors , Venous Thromboembolism/etiology
14.
Rev Gastroenterol Mex ; 75(4): 405-11, 2010.
Article in Spanish | MEDLINE | ID: mdl-21169107

ABSTRACT

INTRODUCTION: Recently it has been reported that prevalence of fructose intolerance (FI) in patients with functional gastrointestinal disorders range between 38% -75%. OBJECTIVE: To determine the prevalence of FI in subjects diagnosed with irritable bowel syndrome (IBS). METHODS: We studied 25 subjects (17 women, average age 36 years) with IBS (Rome II) and 25 healthy controls (14 women, mean age 37 years) who underwent a breath test after oral loading with fructose (Gastrolyzer ®, Bedfont Scientific Ltd., UK). The load consisted of 25 grams of fructose dissolved in 250 ml of water (10% solution). Breath test analysis of the particles per million (ppm) of hydrogen exhaled were performed every 15 minutes for 3 hours. The fructose breath test was considered positive when concentrations of hydrogen were higher than at 20 ppm or a raising greater than 5 ppm in 3 consecutive samples was detected. RESULTS: According to the Rome II criteria, 10 patients (40%) had IBS-C, 9 (36%) had IBS-D and 6 (24%) had IBS-M. Thirteen (52%) of IBS patients had IF, while only 4 (16%) of control subjects (p = 0.01). Patients with IBS and fructose intolerante tend to suffering from diarrhea predominant IBS (p = 0.053). CONCLUSIONS: Fructose intolerance may be responsible for gastrointestinal symptoms in at least half of IBS patients, especially in the group of patients with IBS-D.


Subject(s)
Fructose Intolerance/epidemiology , Fructose Intolerance/etiology , Irritable Bowel Syndrome/complications , Adolescent , Adult , Aged , Case-Control Studies , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Prevalence , Young Adult
15.
Plant Dis ; 94(10): 1262, 2010 Oct.
Article in English | MEDLINE | ID: mdl-30743603

ABSTRACT

Potato virus Y (PVY) has been reported in potato crops in Mexico (3), with tobacco necrotic variants found in the central State of Mexico (4). Nevertheless, many individual states are currently declared PVY free and distribution of individual strains of PVY in potato in different states of Mexico and in different solanaceous crops had not yet been studied. A limited field PVY survey was conducted on potato in the State of Chihuahua in August 2009. More than 900 random potato leaf samples were collected from cvs. Snowden, Atlantic, FL1867, Felsina, Fianna, Gigant, and Alpha. Seven were found to be PVY-positive and had been collected from cvs. Fianna, Snowden, and FL1867. The PVY status of the collected samples was initially determined with the PVY-specific Immunostrips (Bioreba, Reinach, Switzerland) and by double-antibody sandwich-ELISA using the polyclonal PVY detection kit (Agdia, Elkhart, IN). To determine the strain specificity of these PVY isolates following ELISA tests, the infected original samples were inoculated onto tobacco plants at the four-leaf stage and symptom appearance and development were observed for 8 weeks side-by-side with control isolates PB-Oz (PVYO), N4 (PVYNTN), and Mont (PVYN) (1), followed by the standard PVY strain typing by reverse transcription (RT)-PCR (2). Only one of the PVY-positive samples, originally from symptomless potato cv. Fianna, induced systemic PVY infection in tobacco by producing stunting, mosaic, and vein clearing. No systemic vein necrosis, characteristic of isolates Mont and N4, was observed in Nicotiana tabacum cvs. Burley, Xanthi, or Samsun after inoculation with this isolate during all 8 weeks of observation. This isolate, PVY-M3, was typed as a PVY recombinant by RT-PCR, with two recombinant junctions characteristic of European PVYNTN strains (2). It was further analyzed by triple-antibody sandwich-ELISA using four PVYO and PVYN strain-specific monoclonal antibodies. Monoclonals 1F5 (Agdia) and SASA-N (Scottish Agriculture Science Agency [SASA], Edinburgh) reacted to this isolate and identified PVY-M3 serologically as PVYN serotype, characteristic of other PVYNTN recombinants. Monoclonals MAb2 (Agdia) and SASA-O (SASA), specific to PVYO and PVYC strains, did not react to PVY-M3. Taken together, the combination of biological, serological, and molecular characteristics define this recombinant isolate from Mexico as belonging to the same PVY strain group represented by the isolate PVY-L26 (1). To our knowledge, this is the first report of such an unusual PVYNTN recombinant strain from Mexico. Presence of this isolate, with no vein necrotic symptoms induced on tobacco and with PVYNTN genome, will necessitate development of new detection methods for the seed potato industry in Mexico. References: (1) X. Hu et al. Virus Res. 143:68, 2009. (2) J. L. Lorenzen et al. Plant Dis. 90:935, 2006. (3) L. P. Moreno et al. Rev. Mex. Fitopatol. 22:187, 2004. (4) V. R. Ramirez-Rodriguez et al. Virol. J. 6:48, 2009.

16.
Rev Alerg Mex ; 57(6): 208-14, 2010.
Article in English | MEDLINE | ID: mdl-21944489

ABSTRACT

Although various mechanisms involving antibodies and various cell types participate, a Thl and Th2 cells imbalance seems to play a central role for allergy development. Other lymphocyte subpopulations, such as Th17, CD4 FOXP3, and Th9 positive regulatory T lymphocytes may also be involved in the allergic response. Regulatory processes are an appealing target for therapeutic approaches aiming to solve allergic reactions by restoring the delicate balance within the immune system. Transfer factor (TF) or dialyzable leukocyte extract is meant to transfer cell-mediated immunity from immune competent donors to unsensitized or deficient recipients. A PubMed search on the current knowledge on TF indicates that TF may restore the Th1/Th2 balance and improve immune regulatory mechanisms of patients receiving it. Our preliminary results demonstrate that TF induces mRNA expression of IFN-g, osteopontin, RANTES, and hBD-2 in human healthy subjects. TF has been used to treat a variety of immune dysfunction related-pathologies, such as allergy, autoimmunity, immunodeficiencies, infectious diseases and tumors. Patients receiving TF together with their conventional treatment often have better clinical evolution than without it, as we have witnessed, adding TF to the usual medical treatment of allergic diseases as an attempt to provide allergic patients with those regulatory elements that they apparently lack but require to achieve properly regulated immune responses and thus obtain a faster and better resolution of allergic reactions.


Subject(s)
Hypersensitivity , Transfer Factor , CD4-Positive T-Lymphocytes , Cytokines , Humans , Hypersensitivity/immunology , Immunity, Cellular , T-Lymphocytes, Regulatory , Th2 Cells
17.
Ginecol Obstet Mex ; 76(2): 113-7, 2008 Feb.
Article in Spanish | MEDLINE | ID: mdl-18798404

ABSTRACT

Cryopreservation of human oocytes represents a solution for ethic conflict about frozen embryo storage for patients with risk to develop ovarian hyperstimulation syndrome; also is an available technique to preserve fertility in women with cancer under treatment, in poor response patients, in case of premature ovarian failure or aging and for other medical or social conditions that require to delay pregnancies, as well as to make easier oocyte donation programs. This paper reports two cases of successful pregnancies after embryo and oocyte vitrification, as well as their results. The technique of vitrification with the cryotop method is an excellent alternative, efficient, fast and cheap for oocyte and embryo cryopreservation with high ranges of fertilization, cleavage and pregnancies with a normal evolution.


Subject(s)
Cryopreservation/methods , Embryo Transfer , Adult , Embryo Culture Techniques , Ethylene Glycol , Female , Humans , Infant, Newborn , Male , Middle Aged , Oocytes , Pregnancy , Pregnancy Outcome , Pregnancy, Multiple , Solutions , Sperm Injections, Intracytoplasmic
18.
Rev Latinoam Microbiol ; 43(4): 177-82, 2001.
Article in English | MEDLINE | ID: mdl-17061506

ABSTRACT

Cytomegalovirus (CMV) infection in immunocompromised host is an important cause of morbidity and mortality. The protective immunity against the virus is both humoral and cellular. Immunologic mechanisms in rejection as in the immune response against CMV infection are similar but there is difficult to separe as histologic and clinically independent events. At least eight different genes of CMV are homologous to human proteins related to the immune response. The potential role of these genes with homology to human genes can be at different levels. The relevance that immunodominant antigens have on the natural control of CMV infection, suggests that the future design of a vaccine directed to protecting from disease those susceptible to primary infection, in an immunocompromised state, should involve a combination of antigens that include pp65, IE1-exon 4 and gB as a recombinant proteins.


Subject(s)
Cytomegalovirus Infections/immunology , Cytomegalovirus/immunology , Graft Rejection/etiology , Postoperative Complications/immunology , Transplantation Immunology , Antibodies, Viral/immunology , Antigens, Viral/immunology , Cytomegalovirus/genetics , Cytomegalovirus/pathogenicity , Cytomegalovirus Infections/complications , Graft Rejection/immunology , Graft Rejection/prevention & control , Humans , Immunity, Cellular , Immunocompromised Host , Immunodominant Epitopes/immunology , Immunosuppressive Agents/adverse effects , Molecular Mimicry , Postoperative Complications/etiology , Viral Proteins/physiology , Virus Activation
19.
Ginecol Obstet Mex ; 67: 50-2, 1999 Feb.
Article in Spanish | MEDLINE | ID: mdl-10327764

ABSTRACT

A pregnant woman may be infected up to a 90% by intestine parasites, and it all depends on the geographical area associated to the environmental factors allowing this to be spread. The abdominal obstruction related to the pregnancy is rare due to the fact that it only happens in one out of 2,500-6,000 pregnancies. This occlusion, when given by Ascaris lumbricoides, is even more complicated due to the lack of medical literature reference, and thus being unable to make any comparisons. A 45-year old pregnant woman, with several births and multi-pregnancies presenting an acute abdomen by intestinal obstruction through out this helmint. She was pacticed an exploratory laparotomy with the evacuation of several ascaris throughout and enterostomy, and then during the 37th week, she gave birth by means of an eutocic labor work to a healthy female product weighting 2.825 kgs. The anatomopathology study of the placenta shows no alterations. The nosology of the intestinal obstruction by ascariasis during the pregnancy, and out of it, are very similar and could only be affected by late diagnosis of the pregnant woman due to anatomical and physiological changes, increasing the mother's and the fetus morbi-mortality. In Mexico, there are endemic areas where it would be convenient to identify the characteristical eggs in the mother's stool due to the fact that if an advanced pathology is not put in place, it does produce states of maternal malnutrition, anaemia, abdominal pain and low weigh product at the moments of its birth.


Subject(s)
Ascariasis/complications , Intestinal Obstruction/etiology , Pregnancy Complications, Parasitic/parasitology , Female , Humans , Intestinal Obstruction/parasitology , Middle Aged , Pregnancy
20.
Appl Environ Microbiol ; 65(5): 2049-53, 1999 May.
Article in English | MEDLINE | ID: mdl-10223999

ABSTRACT

Most strains of the insecticidal bacterium Bacillus thuringiensis have a combination of different protoxins in their parasporal crystals. Some of the combinations clearly interact synergistically, like the toxins present in B. thuringiensis subsp. israelensis. In this paper we describe a novel joint activity of toxins from different strains of B. thuringiensis. In vitro bioassays in which we used pure, trypsin-activated Cry1Ac1 proteins from B. thuringiensis subsp. kurstaki, Cyt1A1 from B. thuringiensis subsp. israelensis, and Trichoplusia ni BTI-Tn5B1-4 cells revealed contrasting susceptibility characteristics. The 50% lethal concentrations (LC50s) were estimated to be 4,967 of Cry1Ac1 per ml of medium and 11.69 ng of Cyt1A1 per ml of medium. When mixtures of these toxins in different proportions were assayed, eight different LC50s were obtained. All of these LC50s were significantly higher than the expected LC50s of the mixtures. In addition, a series of bioassays were performed with late first-instar larvae of the cabbage looper and pure Cry1Ac1 and Cyt1A1 crystals, as well as two different combinations of the two toxins. The estimated mean LC50 of Cry1Ac1 was 2.46 ng/cm2 of diet, while Cyt1A1 crystals exhibited no toxicity, even at very high concentrations. The estimated mean LC50s of Cry1Ac1 crystals were 15.69 and 19.05 ng per cm2 of diet when these crystals were mixed with 100 and 1,000 ng of Cyt1A1 crystals per cm2 of diet, respectively. These results indicate that there is clear antagonism between the two toxins both in vitro and in vivo. Other joint-action analyses corroborated these results. Although this is the second report of antagonism between B. thuringiensis toxins, our evidence is the first evidence of antagonism between toxins from different subspecies of B. thuringiensis (B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. israelensis) detected both in vivo and in vitro. Some possible explanations for this relationship are discussed.

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