Population dynamics of mites in slow-release sachets used in biological control: a new study methodology.

Predatory mite species (Acari: Phytoseiidae) are essential tools in the biological control of greenhouses pests. The natural enemies can be released directly into a crop. A better, partly preventive system is to place slow-release sachets on the plants. Inside such sachets is a factitious prey's food substrate-which also acts as refuge-and the predator. The objective of this study was to develop a new methodology to evaluate the population dynamics of this sachet system, based on the factitious prey Carpoglyphus lactis and the predatory mite Amblyseius swirskii. Through two tests carried out under laboratory conditions, the sachets were first compared to the traditional extraction method that uses Berlese-Tullgren funnels and an extraction method using flotation in hexane. The latter method proved more effective at sampling the motile states (larvae, nymphs, and adults), both for the predatory species and for the factitious prey, extracting up to 3.7 × more mites than the Berlese-Tullgren funnel. Second, the population dynamics of both mite species was studied in a laboratory test, both inside and outside the sachets. In this way, a positive correlation was demonstrated between the number of predatory mites and the number of prey mites inside the sachets. Conversely, no correlation was found between the interior population of predatory mites and the number that venture outside. We can conclude that hexane extraction is very useful both in quality control of predatory mites and in studying how the sachets behave when faced with various factors.

Spatial and trophic preferences of jumbo squid Dosidicus gigas (D'Orbigny, 1835) in the central Gulf of California: ecological inferences using stable isotopes.

RATIONALE: The jumbo squid Dosidicus gigas is a fishery resource of considerable economic and ecological importance in the Mexican Pacific. Studies on its habitat preferences are needed to understand recent fluctuations in the abundance and availability of the species. Stable isotope analysis allows us to infer ecological aspects such as spatial distribution and trophic preferences. METHODS: We used an isotope ratio mass spectrometer, automated for carbonate analysis, and coupled to an elemental analyzer, to determine the isotopic composition of statoliths (δ18 O and δ13 C values) and beaks (δ13 C and δ15 N values) from 219 individuals caught over two fishing seasons (2007 and 2009) off the coast of Santa Rosalía, in the central Gulf of California. We used these isotopic ratios to assess variation in spatial and trophic preferences by sex, size, and fishing season. RESULTS: In the 2009 group, we observed significant differences in statolith δ13 C values and beak δ13 C and δ15 N values between males and females. Between size groups, we observed significant differences in statolith δ18 O and δ13 C values in 2007 and in beak δ13 C and δ15 N values during both seasons. Both seasons were characterized by high overlap in δ18 O and δ13 C values between sexes and in 2009 between size groups. We observed low trophic overlap between sexes in 2009 and between size groups during both seasons. CONCLUSIONS: The isotopic ratios from statoliths and beaks indicate that D. gigas has changed its spatial and trophic preferences, a shift that is probably related to changes in the species' diet. This intraspecific variation in preferences could be related to characteristics such as size, which may influence squid distribution preferences.

Distribution, bioaccumulation, and trace element transfer among trophic levels in the southeastern Gulf of California.

Our understanding of the trophic transfer of pollutants in marine subtropical ecosystems remains limited due to the complexity of their food webs. Thus, we aimed to evaluate Cd, Cu, Mn, Pb, and Zn sources, incorporation, and trophodynamics throughout the food web of the southeastern Gulf of California by stomach content analysis, stable isotope analysis, isotope mixing models, and trace element analysis in biological and environmental matrices. The food web comprised three main trophic guilds (TG1, TG2, and TG3). The bioaccumulation of Cd and Zn from seawater was efficient (> 1000) in TG2 and TG3. Bioaccumulation factor from sediment (BSAF >1) evidenced of Cd in all trophic guilds. In addition, non-trophic Cd relationships were identified in the food web. Based on the trophic magnification factor (TMF), Mn and Pb showed biodilution (TMFMn = 0.38; TMFPb = 0.16), while Cu and Zn exhibited biomagnification (TMFCu = 2.08; TMFZn = 3.31).

Variation of δ18O in otoliths of Stellifer lanceolatus and Eucinostomus gula environmental change indicator in Terminos Lagoon, Mexico.

Environmental changes have been associated with natural climatic variability or human activity. Water resources management is, perhaps, the most drastic change observed in the coastal environment. However, external forcings such as the El Niño event have important implications in the global and regional hydrological balance. These environmental changes have an impact on the density and biomass of the ichthyofauna in the Terminos Lagoon (TL) for the past 30 years, presumably, associated with variations in the temperature and surface salinity of the sea. Therefore, in the present study, δ18O was quantified in otoliths of two important species due to their dominance: Stellifer lanceolatus and Eucinostomus gula, and to understand the environmental changes reflected in both species. The δ18O was analyzed in otoliths of these two species captured in 1998/1997, 2006/2007 and 2016/2017 and were compared with in situ temperature and salinity data. Sea surface temperature and salinity increased by 2 °C and 9, respectively, between 1997 and 2017. Stellifer lanceolatus δ18O values was in isotopic equilibrium with seawater calcite; while, E. gula is not in isotopic equilibrium. The δ18O of S. lanceolatus and E. gula varied significantly with the increase in salinity (R2 = 0.8987 and R2 = -0.2964) and not with the sea surface temperature. S. lanceolatus is an excellent bioindicator of changes in sea surface salinity in this region of the Gulf of Mexico.

Genetic diversity and drug resistance of Mycobacterium tuberculosis in Ecuador.

BACKGROUND: The genetic diversity of Mycobacterium tuberculosis in Quito, Ecuador is not well known. OBJECTIVE: To investigate mutations related to drug resistance and bacterial genotypes in M. tuberculosis strains in Ecuador. DESIGN: This was a retrospective study of M. tuberculosis isolates from 104 patients. Isolates were phenotypically resistant to rifampicin (RMP) and/or isoniazid (INH). The genotype was determined using 24-locus mycobacterial interspersed repetitive units-variable-number tandem repeats (MIRU-VNTR). RESULTS: Isolates showed mutations in the rpoB and katG genes, and the inhA promoter. In rpoB, we found 13 genetic alterations at codons 511, 513, 514, 515, 516, 526 and 531. Forty-six (44.2%) RMP-resistant isolates belonged to codon 531. In katG, there were nine genetic alterations at codons 296, 312, 314, 315, 322, 324 and 351. Fifty-three (51%) INH-resistant isolates belonged to codon 315. Five mutations not previously described were identified in katG: Thr324Ser, Thr314Ala, Ala312Pro, Trp351Stop and deleted G at 296 codon. The Latin American Mediterranean (LAM) (33.7%) and Ghana (30.8%) lineages presented most of the main mutations observed. CONCLUSION: This is the first report from Ecuador; it describes five new mutations in katG and indicates that LAM is the most prevalent lineage.

Síndrome de takotsubo secundario a trastorno emocional adaptativo / Takotsubo syndrome secondary to adaptative emotional disorder

Introducción: El síndrome de takotsubo o cardiomiopatía por stress, se caracteriza por una disfunción sistólica regional transitoria, principalmente del ventrículo izquierdo que simula un infarto agudo de miocardio, pero en ausencia de evidencia angiográfica de enfermedad arterial coronaria obstructiva o rotura aguda de placa. Es la causa del 1-2 % de todos los síndromes coronarios agudos, se requiere de un diagnóstico oportuno y un tratamiento adecuado para evitar la morbimortalidad por esta patología. Objetivo: destacar la importancia de tener en cuenta el síndrome de takotsubo o cardiomiopatía por estrés como diagnóstico diferencial de los pacientes con dolor torácico según la historia clínica y los desencadenantes del dolor. Presentación de caso: Paciente de 50 años de edad con dolor torácico de características típicas posterior a episodio emocional; reporte de electrocardiograma inicial isquemia anterolateral con troponina positiva y falla cardiaca sistólica, angiografía sin alteración en los vasos coronarios, se diagnosticó síndrome de takotsubo. Conclusión: Es importante considerar el síndrome de takotsubo en el diagnóstico diferencial de los pacientes con dolor torácico, evaluando las circunstancias por las cuales se origina el dolor, ya que requiere un manejo médico multidisciplinario.

Introduction: Takotsubo syndrome or stress cardiomyopathy is characterized by a transient regional systolic dysfunction, mainly of the left ventricle that simulates an acute myocardial infarction, but in the absence of angiographic evidence of obstructive coronary artery disease or acute plaque rupture. It is the cause of 1-2 % of all acute coronary syndromes, which requires a timely diagnosis and an adequate treatment to avoid morbidity and mortality from this pathology. Objective: to highlight the importance of taking into account takotsubo syndrome or stress cardiomyopathy as a differential diagnosis in patients with chest pain according to the clinical history and pain triggers. Case presentation: Fifty-year-old patient with typical chest pain after an emotional episode; the initial electrocardiogram reported anterolateral ischemia with positive troponin and systolic heart failure, and the angiography showed no alteration in the coronary vessels, concluding with the diagnosis of Takotsubo syndrome. Conclusion: It is important to consider takotsubo syndrome in the differential diagnosis of patients with chest pain, evaluating the circumstances by which the pain originates since it requires multidisciplinary medical management.

NSC-87877 inhibits DUSP26 function in neuroblastoma resulting in p53-mediated apoptosis.

Dual specificity protein phosphatase 26 (DUSP26) is overexpressed in high-risk neuroblastoma (NB) and contributes to chemoresistance by inhibiting p53 function. In vitro, DUSP26 has also been shown to effectively inhibit p38 MAP kinase. We hypothesize that inhibiting DUSP26 will result in decreased NB cell growth in a p53 and/or p38-mediated manner. NSC-87877 (8-hydroxy-7-[(6-sulfo-2-naphthyl)azo]-5-quinolinesulfonic acid), a novel DUSP26 small molecule inhibitor, shows effective growth inhibition and induction of apoptosis in NB cell lines. NB cell lines treated with small hairpin RNA (shRNA) targeting DUSP26 also exhibit a proliferation defect both in vitro and in vivo. Treatment of NB cell lines with NSC-87877 results in increased p53 phosphorylation (Ser37 and Ser46) and activation, increased activation of downstream p38 effector proteins (heat shock protein 27 (HSP27) and MAP kinase-activated protein kinase 2 (MAPKAPK2)) and poly ADP ribose polymerase/caspase-3 cleavage. The cytotoxicity resulting from DUSP26 inhibition is partially reversed by knocking down p53 expression with shRNA and also by inhibiting p38 activity with SB203580 (4-[4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-1H-imidazol-5-yl]pyridine). In an intrarenal mouse model of NB, NSC-87877 treatment results in decreased tumor growth and increased p53 and p38 activity. Together, these results suggest that DUSP26 inhibition with NSC-87877 is an effective strategy to induce NB cell cytotoxicity in vitro and in vivo through activation of the p53 and p38 mitogen-activated protein kinase (MAPK) tumor-suppressor pathways.

[Early intervention in infants with intrauterine growth retardation: its effects on neuropsychological development]. / Intervención temprana en infantes con retraso en crecimiento intrauterino: sus efectos en el desarrollo neuropsicológico.

Forty-eight term infants in a tertiary center in Puerto Rico during 1985-86 were monitored prospectively since birth completing a neuropsychological evaluation using the Mental Developmental Index of Bayley Scales. All infants were free from perinatal complications and chronic diseases by clinical evaluation. 25 infants with intrauterine growth retardation (IUGR) and 23 adequate for gestational age (AGA) infants were evaluated. Fourteen IUGR infants were controls and eleven IUGR infants were intervened. However, all AGA infants were used as controls. Mother-infant relationship at one month was scored and none of intervened infants had poor neuropsychological behavior with normal or near normal MDI values. Other relationships and possible explanations are discussed in the article.

A small-molecule inhibitor of UBE2N induces neuroblastoma cell death via activation of p53 and JNK pathways.

Neuroblastoma (NB) is the most common extracranial neoplasm in children. In NB, loss of p53 function is largely due to cytoplasmic sequestration rather than mutation. Ubiquitin-conjugating enzyme E2 N (UBE2N), also known as Ubc13, is an E2 ubiquitin-conjugating enzyme that promotes formation of monomeric p53 that results in its cytoplasmic translocation and subsequent loss of function. Therefore, inhibition of UBE2N may reactivate p53 by promoting its nuclear accumulation. Here, we show that NSC697923, a novel UBE2N inhibitor, exhibits potent cytotoxicity in a panel of NB cell lines evidenced by its ability to induce apoptosis. In p53 wild-type NB cells, NSC697923 induced nuclear accumulation of p53, which led to its increased transcriptional activity and tumor suppressor function. Interestingly, in p53 mutant NB cells, NSC697923 induced cell death by activating JNK pathway. This effect was reversible by blocking JNK activity with its selective inhibitor, SP600125. More importantly, NSC697923 impeded cell growth of chemoresistant LA-N-6 NB cell line in a manner greater than conventional chemotherapy drugs doxorubicin and etoposide. NSC697923 also revealed in vivo antitumor efficacy in NB orthotopic xenografts. Taken together, our results suggest that UBE2N is a potential therapeutic target in NB and provide a basis for the rational use of UBE2N inhibitors like NSC697923 as a novel treatment option for NB patients.

USP7 inhibitor P22077 inhibits neuroblastoma growth via inducing p53-mediated apoptosis.

Neuroblastoma (NB) is a common pediatric cancer and contributes to more than 15% of all pediatric cancer-related deaths. Unlike adult tumors, recurrent somatic mutations in NB, such as tumor protein 53 (p53) mutations, occur with relative paucity. In addition, p53 downstream function is intact in NB cells with wild-type p53, suggesting that reactivation of p53 may be a viable therapeutic strategy for NB treatment. Herein, we report that the ubiquitin-specific protease 7 (USP7) inhibitor, P22077, potently induces apoptosis in NB cells with an intact USP7-HDM2-p53 axis but not in NB cells with mutant p53 or without human homolog of MDM2 (HDM2) expression. In this study, we found that P22077 stabilized p53 by inducing HDM2 protein degradation in NB cells. P22077 also significantly augmented the cytotoxic effects of doxorubicin (Dox) and etoposide (VP-16) in NB cells with an intact USP7-HDM2-p53 axis. Moreover, P22077 was found to be able to sensitize chemoresistant LA-N-6 NB cells to chemotherapy. In an in vivo orthotopic NB mouse model, P22077 significantly inhibited the xenograft growth of three NB cell lines. Database analysis of NB patients shows that high expression of USP7 significantly predicts poor outcomes. Together, our data strongly suggest that targeting USP7 is a novel concept in the treatment of NB. USP7-specific inhibitors like P22077 may serve not only as a stand-alone therapy but also as an effective adjunct to current chemotherapeutic regimens for treating NB with an intact USP7-HDM2-p53 axis.

Spatial and emotional memory in aged rats: a behavioral-statistical analysis.

Age-related impairment in synaptic plasticity, like long-term potentiation (LTP), has been repeatedly reported. We had shown that late stages of LTP in the rat dentate gyrus can be modulated by emotional factors, but this is impaired by aging. In the present study we have searched for possible impairments in emotional and spatial memory tasks that may correspond to the impaired reinforcement observed at the cellular level. We have trained young and aged animals in a battery of tests: exploration (open field) object recognition, anxiety (plus maze) fear conditioning and spatial memory (Morris' water maze (MWM)). The open field, anxiety, and novelty recognition showed no age differences except a reduced velocity in aged rats. Emotional and contextual memories were preserved, but acquisition was slightly impaired. Age-dependent impairments appeared in spatial memory, evaluated in terms of latency and distance to reach the hidden escape platform in the water maze task, but these were not related with impairments in other tests, in particular there was no relation between spatial and emotional memory impairments. Age-related impairments in different paradigms were caused by different independent factors that did not correlated with each other.

Phylogeography and molecular epidemiology of Papaya ringspot virus.

Papaya ringspot virus (PRSV) is the most important virus affecting papaya and cucurbit plants in tropical and subtropical areas. PRSV isolates are divided into biotypes P and W: both the P and W types naturally infect plants in the family Cucurbitaceae, whereas the P type naturally infects papaya (Carica papaya). Understanding the origin and nature of the PRSV genetic diversity and evolution is critical for the implementation of control strategies based on cross-protection and the deployment of transgenic plants that show resistance to virus isolates highly similar to the transgene. The molecular epidemiology of PRSV was evaluated by analyzing the nucleotide sequence of the capsid protein (CP) and helper component-proteinase (HC-Pro) genes of isolates from around the world, including newly characterized ones from Colombia and Venezuela, using a relaxed molecular clock-based approach and a phylogeographic study. Our results confirm previous estimates on the origin of PRSV around 400 years ago and suggest distinct dispersion events from the Indian Peninsula to the rest of Asia, via Thailand, and subsequently to the Americas. A historical reconstruction of the P- and W-type characters in the phylogenetic study supports the need to revise the hypothesis that PRSV-P derives from PRSV-W since our results suggest that the ancestral state could be either of the two biotypes. Moreover, estimates of epidemic growth predict an increasing genetic diversity of the virus over time that has direct implications for control strategies of PRSV based on cross-protection and the use of transgenic plants.

Varying genetic diversity of Papaya ringspot virus isolates from two time-separated outbreaks in Jamaica and Venezuela.

Coat protein sequences of 22 Papaya ringspot virus isolates collected from different locations in Jamaica and Venezuela in 1999 and 2004, respectively, were determined and compared with sequences of isolates from earlier epidemics in 1990 and 1993. Jamaican isolates collected in 1999 exhibited nucleotide sequence identities between 98 and 100% but shared lower identities of 92.2% with an isolate collected in 1990. Isolates from the 2004 epidemic in Venezuela exhibited more heterogeneity, with identities between 88.7 and 98.8%. However, isolates collected in 1993 were more closely related (97.7%). The viral populations of the two countries are genetically different and appear to be changing at different rates; presumably driven by introductions, movement of plant materials, geographical isolation, and disease management practices.

Occurrence of aflatoxins in selected colombian foods.

A survey of aflatoxin contamination in selected Colombian foods was conducted over a 12-month period on a total of 248 samples. Samples were collected in supermarkets, retail stores and stock centres and were grouped into five categories: (1) corn and corn products, (2) cereal grains, (3) rice and rice products, (4) legume seeds; and (5) snacks and breakfast cereals. Aflatoxins were identified and quantitated using a liquid chromatographic technique with a limit of detection of 1 ng/g for each aflatoxin. Aflatoxins were detected in 14 of 109 samples of corn and corn products, 4 of 40 samples of rice and rice products, 2 of 30 samples of legume seeds, and 2 of 11 samples of snacks and breakfast cereals. None of the cereal grains samples analysed contained detectable levels of aflatoxins. Twelve of the total of 22 positive samples exceeded the maximum tolerable level of aflatoxin B1 adopted in most countries (5 ng/g); 10 of these 12 samples corresponded to corn and corn products. The results of the present study indicate that aflatoxin B1 contamination in certain foods in Colombia is a major public health concern. Continuous monitoring of aflatoxin B1 levels in Colombian foods is advised.

[Adenomatous polyps in colon and rectum after cholecystectomy]. / Pólipos adenomatosos en colon y recto despues de colecistectomía.

The frequency of rectal and colonic polyps was compared in 33 patients with history of cholecystectomy and 37 patients without it. The data were evaluated retrospectively from our medical bank records. We found a major incidence of adenomatous polyps in the group of patients with cholecystectomy, the same in females as in males, with a female prevalence in 2.7:1 ratio in contrast with the group without surgery, where the ratio was 1.5:1 with a male prevalence. We didn't find any association between cholecystectomy and colorectal cancer. All the patients with adenocarcinoma were in the group without cholecystectomy.

[Gastric cancer and routine upper digestive endoscopy]. / Cáncer gástrico y endoscopia digestiva superior de rutina.

In this paper we analyzed 5,401 upper G.I. endoscopies performed in a period of 5 years (1985-89), in the Gastroenterology Service at Hospital Jesús Yerena, in Caracas, Venezuela. We found 53 cases of stomach cancer, only 2 of them were early gastric cancer. We studied personal and epidemiological data, symptoms, place of the lesion, treatment, surgical mortality, macroscopic morphology and histopathology. We discuss the results concluding that: cancer of the stomach is a prevalent disease in our Hospital; that fibrogastroscopy is a very good diagnostic procedure; that we must organize a Program of Early Detection for this disease and that we should improve the Oncological Register.

[Level of knowledge of lepers from the city of La Habana about their disease]. / Nivel de conocimientos de los enfermos de lepra de ciudad de La Habana en relación con su padecimiento.

The conclusions herein reported were derived from a study of the perceptions of the general public on leprosy compared with the concepts held by patients. This paper is based on a survey developed accordingly, which was applied to 150 patients and 100 healthy individuals in Havana City. Results show the need for increasing the Health Education provided patients.

Bordetella parapertussis infection in children: epidemiology, clinical symptoms, and molecular characteristics of isolates.

The clinical trial conducted in Italy to evaluate the efficacy of acellular pertussis vaccines provided an opportunity to estimate the frequency of clinical infections with Bordetella parapertussis and to compare the clinical characteristics of children suffering from Bordetella pertussis illness with those of children with B. parapertussis illness. This study dealt with 76 B. parapertussis infections diagnosed from a population of 15,601 children participating in the follow-up of suspected cases of pertussis. An overall incidence of 2.1 cases of laboratory-confirmed parapertussis per 1,000 person-years was observed. Children affected by B. parapertussis infections showed a less severe clinical picture both in the duration of symptoms and in the percentage of patients affected, even when compared with vaccinated children with pertussis. To characterize the isolated strains, we performed assays for susceptibility to erythromycin and sulfamethoxazole-trimethoprim, and we examined the genomic DNAs by pulsed-field gel electrophoresis. The results showed a high degree of genetic stability among B. parapertussis strains regardless of time of collection and geographical distribution.

Detection of Bm86 antigen in different strains of Boophilus microplus and effectiveness of immunization with recombinant Bm86.

The control of tick populations by using conventional strategies poses several problems, including the appearance of organophosphate resistant strains, among others. The possibility of using alternative strategies such as vaccination with tick antigens has been suggested by several authors. One particular antigen (Bm86) has been described and shown to be able to induce a protective immunity against the cattle tick Boophilus microplus. In this paper we demonstrate by means of immunohistochemical staining that this antigen is conserved among several strains of this species. These results correlate with those showing that animals vaccinated with a preparation of recombinant Bm86 were protected against challenge with the four different strains tested, including one resistant to organophosphates. These results favour the immunization with recombinant Bm86 for the control of the cattle tick B. microplus.

[Report pf the first case of lymphogranuloma venereum (LGV) in an HIV seropositive patient in Cuba]. / Reporte del primer caso de linfogranuloma venéreo (LGV) en un paciente seropositivo para VIH en Cuba.

The most important clinical and epidemiological aspects of the lymphogranuloma venereum as a sexually-transmitted disease are described. We present a summary of the clinical history of an HIV-positive patient who presented with a tumoral lesion in the inguinal region presumptive of lymphogranuloma venereum. The diagnostic value of the polymerase chain reaction (PCR) technique for the establishment of an accurate diagnosis is stressed the epidemiological importance of the report of this sexually-transmitted disease in an HIV-positive patient for the first time in Cuba is also pointed out. A good response was attained with Doxycycline.