Immune and oxidative stress biomarkers in pediatric psychosis and psychosis-risk: Meta-analyses and systematic review.

OBJECTIVE: While genetic and cohort studies suggest immune and reduction/oxidation (redox) alterations occur in psychosis, less is known about potential alterations in children and adolescents. METHODS: We conducted a systematic review to identify immune and redox biomarker studies in children and adolescents (mean age ≤ 18 years old) across the psychosis spectrum: from psychotic like experiences, which are common in children, to threshold psychotic disorders like schizophrenia. We conducted meta-analyses when at least three studies measured the same biomarker. RESULTS: The systematic review includes 38 pediatric psychosis studies. The meta-analyses found that youth with threshold psychotic disorders had higher neutrophil/lymphocyte ratio (Hedge's g = 0.40, 95 % CI 0.17 - 0.64), tumor necrosis factor (Hedge's g = 0.38, 95 % CI 0.06 - 0.69), C-reactive protein (Hedge's g = 0.38, 95 % CI 0.05 - 0.70), interleukin-6 (Hedge's g = 0.35; 95 % CI 0.11 - 0.64), and total white blood cell count (Hedge's g = 0.29, 95 % CI 0.12 - 0.46) compared to youth without psychosis. Other immune and oxidative stress meta-analytic findings were very heterogeneous. CONCLUSION: Results from several studies are consistent with the hypothesis that signals often classified as "proinflammatory" are elevated in threshold pediatric psychotic disorders. Data are less clear for immune markers in subthreshold psychosis and redox markers across the subthreshold and threshold psychosis spectrum. Immune and redox biomarker intervention studies are lacking, and research investigating interventions targeting the immune system in threshold pediatric psychosis is especially warranted.

The landscape of cardiogenic shock: epidemiology and current definitions.

PURPOSE OF REVIEW: Despite novel technologies for treating shock patients, cardiogenic shock mortality remains high. Trends of cardiogenic shock associated with acute myocardial infarction (AMI) have previously been described, though little is known about cardiogenic shock resulting from other causes, which has progressively been documented as a distinct entity from AMI-cardiogenic shock. Herein, we review the evolving epidemiology, novel classification schema, and future perspectives of cardiogenic shock. RECENT FINDINGS: While AMI or mechanical complications of AMI are the most common causes, the incidence of etiologies of cardiogenic shock not related to AMI, particularly acute on chronic heart failure, may be increasing, with a growing burden of noncoronary structural heart disease. SUMMARY: Mortality in cardiogenic shock remains high. Overall, these findings highlight the need to address the lack of effective treatments in this field, particularly for cardiogenic shock caused by diseases other than AMI. Novel classification systems may facilitate cardiogenic shock research.

Screening Marine Natural Products for New Drug Leads against Trypanosomatids and Malaria.

Neglected Tropical Diseases (NTD) represent a serious threat to humans, especially for those living in poor or developing countries. Almost one-sixth of the world population is at risk of suffering from these diseases and many thousands die because of NTDs, to which we should add the sanitary, labor and social issues that hinder the economic development of these countries. Protozoan-borne diseases are responsible for more than one million deaths every year. Visceral leishmaniasis, Chagas disease or sleeping sickness are among the most lethal NTDs. Despite not being considered an NTD by the World Health Organization (WHO), malaria must be added to this sinister group. Malaria, caused by the apicomplexan parasite Plasmodium falciparum, is responsible for thousands of deaths each year. The treatment of this disease has been losing effectiveness year after year. Many of the medicines currently in use are obsolete due to their gradual loss of efficacy, their intrinsic toxicity and the emergence of drug resistance or a lack of adherence to treatment. Therefore, there is an urgent and global need for new drugs. Despite this, the scant interest shown by most of the stakeholders involved in the pharmaceutical industry makes our present therapeutic arsenal scarce, and until recently, the search for new drugs has not been seriously addressed. The sources of new drugs for these and other pathologies include natural products, synthetic molecules or repurposing drugs. The most frequent sources of natural products are microorganisms, e.g., bacteria, fungi, yeasts, algae and plants, which are able to synthesize many drugs that are currently in use (e.g. antimicrobials, antitumor, immunosuppressants, etc.). The marine environment is another well-established source of bioactive natural products, with recent applications against parasites, bacteria and other pathogens which affect humans and animals. Drug discovery techniques have rapidly advanced since the beginning of the millennium. The combination of novel techniques that include the genetic modification of pathogens, bioimaging and robotics has given rise to the standardization of High-Performance Screening platforms in the discovery of drugs. These advancements have accelerated the discovery of new chemical entities with antiparasitic effects. This review presents critical updates regarding the use of High-Throughput Screening (HTS) in the discovery of drugs for NTDs transmitted by protozoa, including malaria, and its application in the discovery of new drugs of marine origin.

Sperm kinematic characterization of alpaca (Vicugna pacos L.) during the reproductive season.

Semen analysis is a key factor when determining the fertility ability in males. South American camelids, and in particular the alpaca, have been studied very little when compared with other farm animals. The aim of this work was to perform the kinematic characterization of alpaca spermatozoa collected directly from the deferent duct by using CASA-Mot (Computer Assisted Semen Analysis for Motility) technology. Samples were obtained every three days throughout the reproductive season during two periods and with a break of seven days in the middle. During both periods, the quality of the sample's motility and kinematics increased over the first two days and then subsequently decreased. This pattern was similar in all animals. It was concluded that the introduction of resting times can be useful to improve sperm quality for artificial insemination purposes in natural conditions.

Changes in use, knowledge, beliefs and attitudes relating to tobacco among nursing and physiotherapy students: a 10-year analysis.

AIM: To analyse changes in prevalence, knowledge, beliefs and attitudes relating to smoking among undergraduate nursing and physiotherapy students over a 10-year period. BACKGROUND: Few studies have been performed to describe changes in the use of tobacco and associated characteristics. DESIGN: This study was a sequential cross-sectional study. METHODS: A self-administered survey was performed during three academic years among nursing and physiotherapy students in a Spanish Faculty of Health Sciences. FINDINGS: The proportion of smokers among nursing and physiotherapy students in 2003, 2008 and 2013 was 29·3%, 24·7% and 18·2% respectively. The ages when participants first smoked did not vary over the years. The Fagerström test showed low nicotine dependence. A significantly high percentage of students stated they were unaware of the link between smoking and bladder cancer and oral leukoplakia. Students declared they were unaware of the association between under-weight new-borns and second-hand smoke. The majority of students recognized that healthcare professionals were role models in society, there being little variation over the years studied. In relation to education and training, the study showed a need to inform students about methods and strategies to help people quit smoking. CONCLUSIONS: The prevalence of smoking among nursing and physiotherapy students decreased over the ten years. Active programmes should be implemented to encourage those university students who smoke to break this habit. The decline over the years in knowledge about smoking provided evidence of a significant deficit in undergraduate training.

Evaluation of the methane paradox in four adjacent pre-alpine lakes across a trophic gradient.

Contrasting the paradigm that methane is only produced in anoxic conditions, recent discoveries show that oxic methane production (OMP, aka the methane paradox) occurs in oxygenated surface waters worldwide. OMP drivers and their contribution to global methane emissions, however, are not well constrained. In four adjacent pre-alpine lakes, we determine the net methane production rates in oxic surface waters using two mass balance approaches, accounting for methane sources and sinks. We find that OMP occurs in three out of four studied lakes, often as the dominant source of diffusive methane emissions. Correlations of net methane production versus chlorophyll-a, Secchi and surface mixed layer depths suggest a link with photosynthesis and provides an empirical upscaling approach. As OMP is a methane source in direct contact with the atmosphere, a better understanding of its extent and drivers is necessary to constrain the atmospheric methane contribution by inland waters.

"I don't want to be a burden" A qualitative study of the beliefs of women with chronic low back pain in relation to their painful experience.

BACKGROUND: Women's pain is still poorly understood. Moreover, maladaptive pain beliefs contribute to the disability associated with low back pain and play a key role in the transition from acute to chronic symptoms. OBJECTIVES: To explore the beliefs of women with non-specific chronic low back pain in terms of nature of symptoms, fears associated with pain, expectations for recovery, family, social and work-related limitations, and perceived self-efficacy. DESIGN AND METHODS: A qualitative study with an interpretative approach was undertaken. Face-to-face, semi-structured individual interviews were performed. Study participants were 10 women with non-specific chronic low back pain living in the Metropolitan Region of Chile. Thematic analysis was used to analyze the data. A deductive process was used to code the text and categorize the data. RESULTS: Participants described maladaptive beliefs about pain, leading to fearful attitudes and low expectations for recovery. These beliefs seemed to perpetuate pain and limit engagement in daily tasks and meaningful activities. Some of these beliefs were associated with information provided by healthcare professions. Despite having maladaptive beliefs, women perceived themselves as self-effective. CONCLUSION: Women with chronic low back pain described a range of different pain beliefs across a complex categorial structure. The contents of such structure may interfere with their decisions about therapeutic options. Their beliefs were often ungrounded in scientific principles, even if the information may have been provided by healthcare providers. Physical therapists would benefit from these findings to improve communication with their patients and assess the role of beliefs in decision-making.

Cardiogenic shock related cardiovascular disease mortality trends in US population: Heart failure vs. acute myocardial infarction as contributing causes.

BACKGROUND: Observational and trial data have revealed significant improvement in cardiogenic shock (CS) mortality due to acute myocardial infarction (AMI) after introducing early coronary revascularization. Less is known about CS mortality due to heart failure (HF), which is increasingly recognized as a distinct entity from AMI-CS. METHODS AND RESULTS: In this nationwide observational study, the CDC WONDER database was used to identify national trends in age-adjusted mortality rates (AAMR) due to CS (HF vs. AMI related) per 100,000 people aged 35-84. AAMR from AMI-CS decreased significantly from 1999 to 2009 (AAPC: -6.9% [95%CI -7.7, -6.1]) then stabilized from 2009 to 2020. By contrast, HF-CS associated AAMR rose steadily from 2009 to 2020 (AAPC: 13.3% [95%CI 11.4,15.2]). The mortality rate was almost twice as high in males compared to females in both AMI-CS and HF-CS throughout the study period. HF-CS mortality in the non-Hispanic Black population is increasing more quickly than that of the non-Hispanic White population (AAMR in 2020: 4.40 vs. 1.97 in 100,000). The AMI-CS mortality rate has been consistently higher in rural than urban areas (30% higher in 1999 and 28% higher in 2020). CONCLUSIONS: These trends highlight the fact that HF-CS and AMI-CS represent distinct clinical entities. While mortality associated with AMI-CS has primarily declined over the last two decades, the mortality related to HF-CS has increased significantly, particularly over the last decade, and is increasing rapidly among individuals younger than 65. Accordingly, a dramatic change in the demographics of CS patients in modern intensive care units is expected.

The influence of cognitive factors in relation to the patients' treatment adherence for non-specific chronic low-back pain. A case series.

INTRODUCTION: The positive effects of exercise programs in relation to chronic low-back pain have been long established and patient adherence has a fundamental role in the impact of the resulting benefits. On the other hand, cognitive factors have shown to be the predictors of poor outcomes in patient suffering from this condition to the point of possibly affecting adherence. OBJECTIVE: To determine the influence of cognitive factors on the adherence to a home exercise program, the patient's pain intensity and their level of disability at a two-month follow-up, specifically regarding patients with non-specific chronic low-back pain (NSCLBP). METHOD: ology: Ten patients with NSLBP underwent a home exercise program. This study was undertaken to assess their adherence rate after two months. The assessment tools included the Visual Analogue Scale (VAS), the Oswestry Disability Index pre-follow-up and post-follow-up (ODI1 and ODI2), the Tampa Kinesiophobia Scale (TSK-11), the Pain Catastrophism Scale (PCS), the Fear-Avoidance Beliefs Questionnaire (FABQ) and the General Self-efficacy Scale (GSS) respectively. RESULTS: There were no significant associations found between adherence and the selected cognitive factors. There was an association between GSS and VAS (R = 0.68, p = 0.031). A clinically relevant improvement of 6.8 points in the mean of ODI2 in relation to ODI1 was observed. CONCLUSION: The influence of cognitive factors on adherence has not been ruled out because the study had a low sample size. Future studies should replicate the evaluation protocol in a larger population.

Deep winter intrusions of urban black carbon into a canyon near Santiago, Chile: A pathway towards Andean glaciers.

Black carbon transport from the Santiago Metropolitan Area, Chile, up to the adjacent Andes Cordillera and its glaciers is of major concern. Its deposition accelerates the melting of the snowpack, which could lead to stress on water supply in addition to climate feedback. A proposed pathway for this transport is the channelling through the network of canyons that connect the urban basin to the elevated summits, as suggested by modelling studies, although no observations have validated this hypothesis so far. In this work, atmospheric measurements from a dedicated field campaign conducted in winter 2015, under severe urban pollution conditions, in Santiago and the Maipo canyon, southeast of Santiago, are analysed. Wind (speed and direction) and particulate matter concentrations measured at the surface and along vertical profiles, demonstrate intrusions of thick layers (up to 600 m above ground) of urban black carbon deep into the canyon on several occasions. Transport of PM down-valley occurs mostly through shallow layers at the surface except in connection with deep valley intrusions, when a secondary layer in altitude with return flow (down-valley) at night is observed. The transported particulate matter is mostly from the vicinity of the entrance to the canyon and uncorrelated to concentrations observed in downtown Santiago. Reanalyses data show that for 10% of the wintertime days, deep intrusions into the Maipo canyon are prevented by easterly winds advecting air pollutants away from the Andes. Also, in 23% of the cases, intrusions proceed towards a secondary north-eastward branch of the Maipo canyon, leaving 67% of the cases with favourable conditions for deep penetrations into the main Maipo canyon. Reanalyses show that the wind directions associated to the 33% anomalous cases are related to thick cloud cover and/or the development of coastal lows.

Effect of the reproductive state of female alpacas on embryonic mortality rate.

OBJECTIVE: To study the effect of the reproductive state of female alpacas (ie, maiden [never bred before], barren [bred but failed to conceive or maintain pregnancy in previous breeding season], or gave birth and currently lactating) on embryonic mortality rate. ANIMALS: 167 female alpacas (54 lactating, 44 barren, and 69 maiden) that ovulated following a single breeding. PROCEDURES: During the first 45 days following breeding, female alpacas underwent periodic transrectal ultrasonography to determine the presence or absence of an embryonic vesicle. Serum progesterone concentrations were determined during the same period. Embryonic survival rate was analyzed for each group of females (lactating, barren, and maiden). RESULTS: The presence of an embryonic vesicle or embryo was positively associated with high serum progesterone concentrations (>2 ng/mL). The embryonic mortality rate in barren females (21/44 [47.7%]) was significantly higher than in maiden (20/69 [29.0%]) and lactating (16/54 [29.6%]) females. In females that underwent embryonic loss (n=57), 3 patterns of events in terms of serum progesterone concentrations were identified: concomitant decrease of serum progesterone concentration and embryonic loss (24/57 [42.1%]), decrease in serum progesterone concentration before embryonic loss (12/57 [21.1%]), and persistent serum progesterone concentrations beyond embryonic loss (21/57 [36.8%]). Patterns of serum progesterone concentration and embryonic loss did not differ significantly among lactating, barren, and maiden female alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Embryonic loss in alpacas occurred without any discernible pattern in serum progesterone concentrations. Barren female alpacas had the highest embryonic mortality rate.

Smoking in nursing students: A prevalence multicenter study.

The role of nursing students as future health promoters of healthy behaviors is influenced by their attitude towards smoking. A cross-sectional study using a self-administered survey was performed to analyze smoking prevalence among undergraduate the nursing students who attend nursing faculties in 2 European countries (Spain and Portugal) during academic period 2015 to 2016. A total of 1469 subjects were surveyed (response rate of 79.8%). An 80% of the students were female with a mean age of 21.9 (4.8) years. The overall prevalence of tobacco use was 18.9%, with an average percentage of 16.2% in Portugal and 18.3% in Spain. Statistical significance was observed in relation to smoke and previous studies (16.4% vs 27.1%; P < .001). Only 1.1% of the students reported using electronic cigarette. 15.8% of smokers started smoking while at university with statistical gender and previous studies differences (P < .001). Fagerström and Richmond test showed low nicotine dependence (2.8 ±â€Š2) and moderate motivation to stop smoking (4.9 ±â€Š3), respectively. Smoking prevalence among nursing students was slightly higher than the general European population. For that reason, measures to reduce tobacco use have to be focused on students and university policies on tobacco control should be a challenge in the future.

Functional expression of a DNA-topoisomerase IB from Cryptosporidium parvum.

Cryptosporidium parvum, one of the most important causative organisms of human diarrheas during childhood, contains a monomeric DNA-topoisomerase IB (CpTopIB) in chromosome 7. Heterologous expression of CpTopIB gene in a budding yeast strain lacking this activity proves that the cryptosporidial enzyme is functional in vivo. The enzymatic activity is comprised in a single polypeptide, which contains all the structural features defining a fully active TopIB. Relaxation activity of the yeast extracts was detected only when CpTopIB ORF was expressed in a yeast expression system showing time and protein dependence under steady state kinetic conditions. The susceptibility of CpTopIB-transformed yeast to the irreversible inhibitor camptothecin and its water-soluble derivatives (topotecan and SN-38) was assessed.

A single preoperative pain neuroscience education: Is it an effective strategy for patients with carpal tunnel syndrome?

Patients undergoing carpal tunnel release surgery may continue to experience pain despite the intervention. This symptom may be modulated by psychosocial factors including depression, catastrophic thinking, and kinesiophobia. Pain neuroscience education (PNE) has been found to be effective when combined with therapeutic exercise in patients with chronic pain, but this strategy has not been evaluated in patients with persistent hand pain. The findings of this study indicate that a single preoperative PNE session in combination with therapeutic exercise does not provide added benefits in comparison to standard preoperative care plus therapeutic exercise. Future studies should evaluate if patients with carpal tunnel release are additionally benefited by the incorporation and consequent behavioural changes of more PNE sessions to multimodal treatment.

[Smoking prevalence evaluation by three different methods among first-year health sciences students at the University of Leon, Spain, 2006]. / Valoración con tres métodos diferentes de la prevalencia de consumo de tabaco en estudiantes de primer curso de ciencias de la salud de la Universidad de León en 2006.

BACKGROUND: Intervention in the prevention and control of the smoking habit among health sciences students in order to improve the beliefs and attitudes of future professionals concerning this serious public health problem. The objective of this study is to compare the validity of three different methods for calculating the prevalence of smokers. METHODS: First-year students at a Health Sciences School. Smoking was evaluated by means of a self-administered questionnaire, the carbon monoxide (CO) in expiratory air and saliva cotinine. The prevalence found using each method, the agreement with the Kappa index and the internal validity of the questionnaire and the cooximetry were evaluated using the cotinine test as the gold standard. RESULTS: A total of 29.3% of the 181 students studied were classified as smokers by some measurement; 26.5% (cotinine), 22.1% (self-stated) and 9.4% (cooximetry). Two thirds of the smokers had low nicotine dependence. Good agreement was found only between the questionnaire and the cotinine test (Kappa Index=73.1%). Compared to the cotinine test, the questionnaire and the cooximetry respectively showed 72.9% and 35.4% sensitivity, and a 96.2% and 100% specificity. According to the questionnaire, 81.5% of the low-dependence smokers tested positive for the cotinine test, 14.5% having tested positive in the cooximetry. CONCLUSIONS: Cooximetry does not seem to be a good method for detecting smokers in this population. The cotinine test and the questionnaire are found to agree well, but the internal validity of the questionnaire in comparison to the cotinine test shows a lesser degree of sensitivity than expected. The gold standard criterion used must be revised for a low-dependence population with possible exposure to second-hand smoke.

The phantom midge menace: Migratory Chaoborus larvae maintain poor ecosystem state in eutrophic inland waters.

Chaoborus spp. (phantom midge) are prevalent in eutrophic inland waters. In Lake Soppen, Switzerland, C. flavicans larvae diurnally migrate between the methane-rich, oxygen-depleted hypolimnion and sediments, and the methane-poor, oxygen-rich epilimnion. Using a combination of experiments and system modelling, this study demonstrated that the larvae's burrowing activities in and out of the sediment perturbed the sediment and re-introduced sequestered phosphorus into the overlying water at a rate of 0.022 µg P ind-1 d-1, thereby exacerbating internal nutrient loading in the water column. Fluxes of sediment methane and other reduced solutes enhanced by the larval bioturbation would consume oxygen and sustain the hypoxic/anoxic condition below the thermocline. In addition to increasing diffusive fluxes, migrating larvae also directly transported methane in their gas vesicles from the deep water and release it in the surface water at a rate of 0.99 nmol CH4 ind-1 d-1, potentially contributing to methane emission to air. As nutrient pollution and climate warming persist or worsen in the coming decades, proliferation of Chaoborus could intensify this positive feedback loop and delay lake recovery.

Puma (Puma concolor) epididymal sperm morphometry.

The Andean puma (Puma concolor) has not been widely studied, particularly in reference to its semen characteristics. The aim of the present study was to define the morphometry of puma sperm heads and classify their subpopulations by cluster analysis. Samples were recovered postmortem from two epididymides from one animal and prepared for morphological observation after staining with the Hemacolor kit. Morphometric data were obtained from 581 spermatozoa using a CASA-Morph system, rendering 13 morphometric parameters. The principal component (PC) analysis was performed followed by cluster analysis for the establishment of subpopulations. Two PC components were obtained, the first related to size and the second to shape. Three subpopulations were observed, corresponding to elongated and intermediate-size sperm heads and acrosomes, to large heads with large acrosomes, and to small heads with short acrosomes. In conclusion, puma spermatozoa showed no uniform sperm morphology but three clear subpopulations. These results should be used for future work in the establishment of an adequate germplasm bank of this species.

Gimatecan and other camptothecin derivatives poison Leishmania DNA-topoisomerase IB leading to a strong leishmanicidal effect.

The aim of this work is the in vitro and ex vivo assessment of the leishmanicidal activity of camptothecin and three analogues used in cancer therapy: topotecan (Hycantim®), gimatecan (ST1481) and the pro-drug irinotecan (Camptosar®) as well as its active metabolite SN-38 against Leishmania infantum. The activity of camptothecin and its derivatives was studied on extracellular L. infantum infrared-emitting promastigotes and on an ex vivo murine model of infected splenocytes with L. infantum fluorescent amastigotes. In situ formation of SDS/KCl precipitable DNA-protein complexes in Leishmania promastigotes indicated that these drugs are DNA topoisomerase IB poisons. The inhibitory potency of camptothecin derivatives on recombinant L. infantum topoisomerase IB was assessed in vitro showing that gimatecan is the most active compound preventing the relaxation of supercoiled DNA at submicromolar concentrations. Cleavage equilibrium assays in Leishmania topoisomerase IB show that gimatecan changes the equilibrium towards cleavage at much lower concentrations than the other camptothecin derivatives and that this effect persists over time. Gimatecan and camptothecin were the most powerful compounds preventing cell growth of free-living L. infantum promastigotes within the same concentration range. All these compounds killed L. infantum splenocyte-infecting amastigotes within the nanomolar range. The amastigote form showed higher sensitivity to topoisomerase IB poisons (with high therapeutic selectivity indexes) than free-living promastigotes. All the compounds assayed poisoned L. infantum DNA topoisomerase IB leading to a strong leishmanicidal effect. Camptothecin derivatives are suitable for reducing the parasitic burden of ex vivo infected splenocytes. The selectivity index of gimatecan makes it a promising drug against this neglected disease.

Lead toxicity in captive and wild Mallards (Anas platyrhynchos) in Spain.

Forty captive Mallards (Anas platyrhynchos), of both sexes, were separated into five groups and dosed with lead shot via oral intubation; one group was used as a control. Lead dosage differed in terms of shot number and size, as well as administration time. One hundred and thirty-five wild mallards were trapped between 1998 and 2001 in the Boada and Nava lagoons near the Canal de Castilla, in the Spanish province of Palencia. Radiologic techniques (ventrodorsal and lateral views) were used to detect lead shot in the gizzard and to determine degradation in dosed birds over time. Heparinized blood samples were taken from wild and captive mallards and blood lead levels were determined using anodic stripping voltammetry with a dropping mercury electrode. Clinical signs, injuries, and body weight were recorded. In approximately 90% of the experimentally dosed mallards, administered shot stayed in their gizzard until it degraded; this took approximately 30 days. Peak lead levels in blood were observed between days 10 and 20, and 10 days following a repeat dosage; males were more sensitive than females to a repeat dosage. During the experimental phase, 34% of birds died, and those that survived had varying degrees of anorexia, lethargy, and a decreased response to external stimulus. Of 135 tested wild mallards, 41% had a blood lead concentration higher than 0.200 microg/g. Lead shot was found embedded in 3.6% of the wild birds and 1.2% had a lead shot pellet in their gizzard.

Cloning expression and characterization of methionine adenosyltransferase in Leishmania infantum promastigotes.

Methionine adenosyltransferase (MAT) catalyzes the synthesis of s-adenosylmethionine (AdoMet), a metabolite that plays an important role in a variety of cellular functions, such as methylation, sulfuration, and polyamine synthesis. In this study, genomic DNA from the protozoan parasite Leishmania infantum was cloned and characterized. L. infantum MAT, unlike mammalian MAT, is codified by two identical genes in a tandem arrangement and is only weakly regulated by AdoMet. L. infantum MAT mRNA is expressed as a single transcript, with the enzyme forming a homodimer with tripolyphosphatase in addition to MAT activity. Expression of L. infantum MAT in Escherichia coli proves that the MAT and tripolyphosphatase activities are functional in vivo. MAT shows sigmoidal behavior and is weakly inhibited by AdoMet, whereas tripolyphosphatase activity has sigmoidal behavior and is strongly activated by AdoMet. Plasmids containing the regions flanking MAT2 were fused immediately upstream and downstream of the luciferase-coding region and transfected into L. infantum. Subsequent examination of luciferase activity showed that homologous expression in L. infantum promastigotes was dramatically dependent on the presence of polypyrimidine tracts and a spliced leader junction site upstream of the luciferase gene, whereas downstream sequences appeared to have no bearing on expression.