Intra- and interspecific diversity in a tropical plant clade alter herbivory and ecosystem resilience.

Declines in biodiversity generated by anthropogenic stressors at both species and population levels can alter emergent processes instrumental to ecosystem function and resilience. As such, understanding the role of biodiversity in ecosystem function and its response to climate perturbation is increasingly important, especially in tropical systems where responses to changes in biodiversity are less predictable and more challenging to assess experimentally. Using large-scale transplant experiments conducted at five neotropical sites, we documented the impacts of changes in intraspecific and interspecific plant richness in the genus Piper on insect herbivory, insect richness, and ecosystem resilience to perturbations in water availability. We found that reductions of both intraspecific and interspecific Piper diversity had measurable and site-specific effects on herbivory, herbivorous insect richness, and plant mortality. The responses of these ecosystem-relevant processes to reduced intraspecific Piper richness were often similar in magnitude to the effects of reduced interspecific richness. Increased water availability reduced herbivory by 4.2% overall, and the response of herbivorous insect richness and herbivory to water availability were altered by both intra- and interspecific richness in a site-dependent manner. Our results underscore the role of intraspecific and interspecific richness as foundations of ecosystem function and the importance of community and location-specific contingencies in controlling function in complex tropical systems.

Patients Living with Arterial Hypertension in Mexico: First Insights of The Mexican Registry of Arterial Hypertension (RIHTA Study).

BACKGROUND: Arterial hypertension is a significant cause of morbidity and mortality in Mexico. However, there is limited data available to understand blood pressure management and cardiometabolic profiles. AIMS: To assess the prevalence of controlled and uncontrolled blood pressure, as well as the prevalence of cardiometabolic risk factors among patients from the Mexican Registry of Arterial Hypertension (RIHTA). METHODS: We conducted a cross-sectional analysis of participants living with arterial hypertension registered on RIHTA between December 2021 and April 2023. We used both the 2017 ACC/AHA and 2018 ESC/ESH thresholds to define controlled and uncontrolled arterial hypertension. We considered eleven cardiometabolic risk factors, which include overweight, obesity, central obesity, insulin resistance, diabetes, hypercholesterolemia, hypertriglyceridemia, low-HDL-C, high-LDL-C, low-eGFR, and high CVD risk. RESULTS: In a sample of 5,590 participants (female: 61%, n=3,393; median age: 64 [IQR: 56-72] years), the prevalence of uncontrolled hypertension varied significantly, depending on the definition (2017 ACC/AHA: 59.9%, 95% CI: 58.6-61.2 and 2018 ESC/ESH: 20.1%, 95% CI: 19.0-21.2). In the sample, 40.43% exhibited at least 5-6 risk factors, and 32.4% had 3-4 risk factors, chiefly abdominal obesity (83.4%, 95% CI: 82.4-84.4), high-LDL-C (59.6%, 95% CI: 58.3-60.9), high-CVD risk (57.9%, 95% CI: 56.6-59.2), high triglycerides (56.2%, 95% CI: 54.9-57.5), and low-HDL-C (42.2%, 95% CI: 40.9-43.5). CONCLUSION: There is a high prevalence of uncontrolled hypertension interlinked with a high burden of cardiometabolic comorbidities in Mexican adults living with arterial hypertension, underscoring the urgent need for targeted interventions and better healthcare policies to reduce the burden of the disease in our country.

Mechanisms Associated with Cognitive and Behavioral Impairment Induced by Arsenic Exposure.

Arsenic (As) is a metalloid naturally present in the environment, in food, water, soil, and air; however, its chronic exposure, even with low doses, represents a public health concern. For a long time, As was used as a pigment, pesticide, wood preservative, and for medical applications; its industrial use has recently decreased or has been discontinued due to its toxicity. Due to its versatile applications and distribution, there is a wide spectrum of human As exposure sources, mainly contaminated drinking water. The fact that As is present in drinking water implies chronic human exposure to this metalloid; it has become a worldwide health problem, since over 200 million people live where As levels exceed safe ranges. Many health problems have been associated with As chronic exposure including cancer, cardiovascular diseases, gastrointestinal disturbances, and brain dysfunctions. Because As can cross the blood-brain barrier (BBB), the brain represents a target organ where this metalloid can exert its long-term toxic effects. Many mechanisms of As neurotoxicity have been described: oxidative stress, inflammation, DNA damage, and mitochondrial dysfunction; all of them can converge, thus leading to impaired cellular functions, cell death, and in consequence, long-term detrimental effects. Here, we provide a current overview of As toxicity and integrated the global mechanisms involved in cognitive and behavioral impairment induced by As exposure show experimental strategies against its neurotoxicity.

Blood pressure telemonitoring and telemedicine, a Latin America perspective.

PURPOSE: To share a Latin-American perspective of the use of telemedicine, together with blood pressure measurements outside the medical office, as a potential contribution to improving access to the health system, diagnosis, adherence, and persistence in hypertension treatment. MATERIAL AND METHODS: A document settled by a Writing Group of Mexico Hypertension Experts Group, Interamerican Society of Hypertension, Epidemiology and Cardiovascular Prevention Council of the Interamerican Society of Cardiology, and National Cardiologist Association of Mexico. RESULTS: In almost all Latin American countries, the health sector faces two fundamental challenges: (1) ensure equitable access to quality care services in a growing population that faces an increase in the prevalence of chronic diseases, and (2) optimise the growing costs of health services, maintaining equity, accessibility, universality, and quality. Telehealth proposes an innovative approach to patient management, especially for chronic conditions, intending to provide remote consultation, education, and follow-up to achieve measurements and goals. It is a tool that promises to improve access, empower the patient, and somehow influence their behaviour about lifestyle changes, improving prevention and reducing complications of hypertension. The clinical practitioner has seen increased evidence that the use of out-of-office blood pressure (BP) measurement and telemedicine are helpful tools to keep patients and physicians in contact and promote better pharmacological adherence and BP control. A survey carried out by medical and scientific institutions showed that practitioners are up-to-date with telemedicine, had internet access, and had hardware availability. CONCLUSIONS: A transcendent issue is the need to make the population aware of the benefits of taking blood pressure to avoid complications of hypertension, and in this scenario, promote the creation of teleconsultation mechanisms for the follow-up of patients diagnosed with hypertension.

What is the context?In almost all Latin American countries, the health sector faces two fundamental challenges: (1) ensure equitable access to quality care services in a growing population that faces an increase in the prevalence of chronic diseases, and (2) optimise the growing costs of health services, maintaining equity, accessibility, universality, and quality.What is new?Telehealth proposes an innovative approach to patient management, especially for chronic conditions, intending to provide remote consultation, education, and follow-up to achieve measurements and goals. It is a tool that promises to improve access, empower the patient, and somehow influence their behaviour about lifestyle changes, improving prevention and reducing complications of hypertension.What is the impact?Needs are always infinite, and resources are finite, so according to the World Health Organisation (WHO), advances in electronic, information, and communication technology point to more significant equity in the provision of services, considering the effectiveness, possibility of refining the rationalisation of health spending, and improving health care for remote populations.A transcendent issue is the need to make the population aware of the benefits of taking blood pressure to avoid complications of hypertension, and in this scenario, promote the creation of teleconsultation mechanisms for the follow-up of patients diagnosed with hypertension.

Blood pressure telemonitoring and telemedicine for hypertension management-positions, expectations and feasibility of Latin-American practitioners. SURVEY carried out by several cardiology and hypertension societies of the Americas.

PURPOSE: To assess the opinion of Latin-American physicians on remote blood pressure monitoring and telehealth for hypertension management. MATERIAL AND METHODS: Cross-sectional survey of physicians residing in Latin-America. The study was conducted by the Mexico Hypertension Experts Group, Interamerican Society of Hypertension, Interamerican Society of Cardiology Epidemiology and Cardiovascular Prevention Council, and National Cardiologist Association of Mexico. An online survey composed of 40 questions using Google Forms was distributed from 7 December 2021, to 3 February 2022. The survey was approved by the GREHTA Ethics Committee and participation was voluntary and anonymous. Multiple logistic regression models were constructed to identify the challenges of telehealth. RESULTS: 1753 physicians' responses were gathered. The responses came from physicians from different Latin-American countries, as follows: 24% from Mexico, 20.6% from Argentina, 14.7% from Colombia, 10.9% from Brazil, 8.7% from Venezuela, 8.2% from Guatemala and 3.2% from Paraguay. Responders with a high interest in carrying out their assistance task through remote telemonitoring reached 48.9% (821), while 43.6% are already currently conducting telemonitoring. A high number, 62%, claimed to need telemonitoring training. There is a direct relation between higher interest in telemonitoring and age, medical specialty, team working, residence in the biggest cities, expectations regarding telemedicine and reimbursement. CONCLUSIONS: Remote monitoring is feasible in Latin-America. General practitioners and specialists from bigger cities seem eager and are self-perceived as well-trained and experienced. Facilities and resources do not seem to be a challenge but training reinforcement and telemedicine promotion is necessary for those physicians less motivated.PLAIN LANGUAGE SUMMARYWhat is the context?Hypertension is one of the leading worldwide modifiable risk factors for premature death. Strong evidence supports that effective treatment of this condition results in a significant reduction of hard outcomes.Only 20%-30% of hypertensive patients are within the blood pressure targets recommended by guidelines in Latin-America. There is an urgent need to implement innovative strategies to reverse this alarming health situation.What is new?Latin-American physicians were highly predisposed to telemonitoring practice. This high motivation was not influenced by hardware or software availability, technological knowledge or experience, by volume of monthly consultations, or by area (private-public) where the care activity is carried out.This high motivation may be supported by the conviction that this practice could be very useful as a complement to face-to-face assistance and a highly effective tool to improve adherence even though respondents considered that just 10% of the patients would prefer telemonitoring over office consultation.What is the impact?Facilities and resources do not seem to be a challenge but training reinforcement and telemedicine promotion is necessary for those physicians less motivated. The general perception is that it is necessary to move forward to resolve legal gaps and financial aspects.Physicians must adapt to changes and develop new communication strategies in a world where the unrestricted access to teleinformation makes patients self-perceived as experts.

Anti-Virulence Properties of Plant Species: Correlation between In Vitro Activity and Efficacy in a Murine Model of Bacterial Infection.

Several plant extracts exhibit anti-virulence properties due to the interruption of bacterial quorum sensing (QS). However, studies on their effects at the preclinical level are scarce. Here, we used a murine model of abscess/necrosis induced by Pseudomonas aeruginosa to evaluate the anti-pathogenic efficacy of 24 plant extracts at a sub-inhibitory concentration. We analyzed their ability to inhibit QS-regulated virulence factors such as swarming, pyocyanin production, and secretion of the ExoU toxin via the type III secretion system (T3SS). Five of the seven extracts with the best anti-pathogenic activity reduced ExoU secretion, and the extracts of Diphysa americana and Hibiscus sabdariffa were identified as the most active. Therefore, the abscess/necrosis model allows identification of plant extracts that have the capacity to reduce pathogenicity of P. aeruginosa. Furthermore, we evaluated the activity of the plant extracts on Chromobacterium violaceum. T3SS (ΔescU) and QS (ΔcviI) mutant strains were assessed in both the abscess/necrosis and sepsis models. Only the ΔescU strain had lower pathogenicity in the animal models, although no activity of plant extracts was observed. These results demonstrate differences between the anti-virulence activity recorded in vitro and pathogenicity in vivo and between the roles of QS and T3S systems as virulence determinants.

Antivirulence Activity of a Dietary Phytochemical: Hibiscus Acid Isolated from Hibiscus sabdariffa L. Reduces the Virulence of Pseudomonas aeruginosa in a Mouse Infection Model.

Hibiscus sabdariffa L. (Hs) calyxes, rich in organic acids, are included in diets in different countries. In recent years, some phytochemicals have been shown to reduce bacterial virulence at sublethal concentrations by interfering with quorum sensing (QS) systems. Therefore, in this study the antivirulence properties of Hs calyxes and two γ-lactones (hibiscus acid [HA] and its methyl ester) in Pseudomonas aeruginosa were analyzed. Acetone and methanol extracts of Hs showed anti-QS activity by inhibiting violacein production (60% to 80% with 250 µg/mL). In molecular docking analysis, the γ-lactones registered a good binding score, which suggests strong interaction with the active site of LasR protein. To verify their effect in vitro, they were isolated from Hs and evaluated in six QS-regulated phenotypes, as well as in ExoU toxin that is released by the type III secretion system (T3SS). At 500 µg/mL they reduced alkaline protease (29-52%) and elastase (15-37%) activity, biofilm formation (∼75%), and swarming (50%), but there was no effect on pyocyanin production, hemolytic activity, or type III secretion. In a mouse abscess/necrosis model, HA at sublethal concentrations (15 and 31.2 µg/mL) affected infection establishment and prevented damage and systemic spread. In conclusion, HA is the first molecule identified with antivirulence properties in Hs with the potential to prevent infections caused by P. aeruginosa.

Familial hypercholesterolemia in Mexico: Initial insights from the national registry.

BACKGROUND: Familial hypercholesterolemia (FH) remains underdiagnosed and undertreated. OBJECTIVE: Report the results of the first years (2017-2019) of the Mexican FH registry. METHODS: There are 60 investigators, representing 28 federal states, participating in the registry. The variables included are in accordance with the European Atherosclerosis Society (EAS) FH recommendations. RESULTS: To date, 709 patients have been registered, only 336 patients with complete data fields are presented. The mean age is 50 (36-62) years and the average time since diagnosis is 4 (IQR: 2-16) years. Genetic testing is recorded in 26.9%. Tendon xanthomas are present in 43.2%. The prevalence of type 2 diabetes is 11.3% and that of premature CAD is 9.8%. Index cases, male gender, hypertension and smoking were associated with premature CAD. The median lipoprotein (a) level is 30.5 (IQR 10.8-80.7) mg/dl. Statins and co-administration with ezetimibe were recorded in 88.1% and 35.7% respectively. A combined treatment target (50% reduction in LDL-C and an LDL-C <100 mg/dl) was achieved by 13.7%. Associated factors were index case (OR 3.6, 95%CI 1.69-8.73, P = .002), combination therapy (OR 2.4, 95%CI 1.23-4.90, P = .011), type 2 diabetes (OR 2.8, 95%CI 1.03-7.59, P = .036) and age (OR 1.023, 95%CI 1.01-1.05, P = .033). CONCLUSION: The results confirm late diagnosis, a lower than expected prevalence and risk of ASCVD, a higher than expected prevalence of type 2 diabetes and undertreatment, with relatively few patients reaching goals. Recommendations include, the use of combination lipid lowering therapy, control of comorbid conditions and more frequent genetic testing in the future.

COVID-19 and the renin, angiotensin, aldosterone system. A complex relationship.

The COVID-19 pandemic has had major negative health, psychological, social and economic repercussions for individuals, families, communities, countries and for humanity in general. The interrelation with age and the presence of chronic non-communicable diseases (hypertension, diabetes, obesity, smoking) seems to go further than what would be explained by the prevalence and distribution of both. The drugs that act on the renin-angiotensin-aldosterone system are in many cases the backbone for the management of these diseases, it has been known for a long time that these drugs significantly increase the expression of receptors for angiotensin conversion enzyme type 2 in the lung tissue. This fact, together with the knowledge that the route of entry of the virus into the cell is precisely the ACE-2 receptor, initiated a hypothesis, based on very low-quality evidence, which quickly became generalized in the media, that the use of these drugs could be negative and that they should be interrupted immediately. The response of practically all Scientific Societies was almost immediate, with the precise indication that treatment with these drugs should not be discontinued, since the evidence of their usefulness is based on very solid and high-quality evidence. Simultaneously, a different hypothesis also appeared, also based on very preliminary evidence, that these drugs are not only harmful but also beneficial, however these medicaments are not yet accepted as agents for the prevention or treatment of this disease or its complications. This review reports current knowledge on the relationship between COVID-19 and SRAA.

La pandemia por COVID-19 ha tenido muy importantes repercusiones negativas, sanitarias, psicológicas, sociales y económicas para las personas, las familias, las comunidades, los países y para las para la humanidad en general. La interrelación con la edad y la presencia de enfermedades crónicas no trasmisibles (hipertensión, diabetes, obesidad, tabaquismo) parece ir mas lejos que lo que explicaría la prevalencia y distribución de ambas. Los medicamentos que actúan sobre el sistema renina-angiotensina-aldosterona, son pilares básicos en el manejo de estas enfermedades. Se sabe de tiempo atrás que estos fármacos aumentan en forma significativa la expresión en el tejido pulmonar de receptores para la enzima de conversión de angiotensina de tipo 2. Este hecho junto con el conocimiento de que la vía de entrada del virus a la célula es precisamente el receptor de ECA-2, inició una hipótesis, basada en evidencia de muy baja calidad, que rápidamente se generalizó en los medios de comunicación, de que el empleo de estos medicamentos podría ser negativo y que deberían suspenderse. La respuesta de prácticamente todas las sociedades científicas fue casi inmediata, con la indicación precisa de que no debería suspenderse el tratamiento con estos fármacos, puesto que la evidencia de su utilidad está basada en una evidencia muy sólida y de gran calidad. Casi simultáneamente también apareció la hipótesis, también basada en evidencia muy preliminar, de que estos medicamentos no solo resultan dañinos sino que son benéficos, tampoco se aceptan todavía como agentes para la prevención o tratamiento de esta enfermedad o sus complicaciones. La presente revisión relata los conocimientos actuales sobre la relación entre COVID-19 y SRAA.

Loss of dominant caterpillar genera in a protected tropical forest.

Reports of biodiversity loss have increasingly focused on declines in abundance and diversity of insects, but it is still unclear if substantive insect diversity losses are occurring in intact low-latitude forests. We collected 22 years of plant-caterpillar-parasitoid data in a protected tropical forest and found reductions in the diversity and density of insects that appear to be partly driven by a changing climate and weather anomalies. Results also point to the potential influence of variables not directly measured in this study, including changes in land-use in nearby areas. We report a decline in parasitism that represents a reduction in an important ecosystem service: enemy control of primary consumers. The consequences of these changes are in many cases irreversible and are likely to be mirrored in nearby forests; overall declines in the region will have negative consequences for surrounding agriculture. The decline of important tropical taxa and associated ecosystem function illuminates the consequences of numerous threats to global insect diversity and provides additional impetus for research on tropical diversity.

Tetradecanoic Acids With Anti-Virulence Properties Increase the Pathogenicity of Pseudomonas aeruginosa in a Murine Cutaneous Infection Model.

Blocking virulence is a promising alternative to counteract Pseudomonas aeruginosa infections. In this regard, the phenomenon of cell-cell communication by quorum sensing (QS) is an important anti-virulence target. In this field, fatty acids (FA) have gained notoriety for their role as autoinducers, as well as anti-virulence molecules in vitro, like some saturated FA (SAFA). In this study, we analyzed the anti-virulence activity of SAFA with 12 to18 carbon atoms and compared their effect with the putative autoinducer cis-2-decenoic acid (CDA). The effect of SAFA on six QS-regulated virulence factors and on the secretion of the exoenzyme ExoU was evaluated. In addition, a murine cutaneous infection model was used to determine their influence on the establishment and damage caused by P. aeruginosa PA14. Dodecanoic (lauric, C12:0) and tetradecanoic (myristic, C14:0) acids (SAFA C12-14) reduced the production of pyocyanin by 35-58% at 40 and 1,000 µM, while CDA inhibited it 62% at a 3.1 µM concentration. Moreover, the SAFA C12-14 reduced swarming by 90% without affecting biofilm formation. In contrast, CDA reduced the biofilm by 57% at 3 µM but did not affect swarming. Furthermore, lauric and myristic acids abolished ExoU secretion at 100 and 50 µM respectively, while CDA reduced it by ≈ 92% at 100 µM. Remarkably, the coadministration of myristic acid (200 and 1,000 µM) with P. aeruginosa PA14 induced greater damage and reduced survival of the animals up to 50%, whereas CDA to 500 µM reduced the damage without affecting the viability of the PA14 strain. Hence, our results show that SAFA C12-14 and CDA have a role in regulation of P. aeruginosa virulence, although their inhibition/activation molecular mechanisms are different in complex environments such as in vivo systems.

COVID-19 y el sistema renina, angiotensina, aldosterona. Una relación compleja / COVID-19 and the renin, angiotensin, aldosterone system. A complex relationship

Resumen La pandemia por COVID-19 ha tenido muy importantes repercusiones negativas, sanitarias, psicológicas, sociales y económicas para las personas, las familias, las comunidades, los países y para las para la humanidad en general. La interrelación con la edad y la presencia de enfermedades crónicas no trasmisibles (hipertensión, diabetes, obesidad, tabaquismo) parece ir mas lejos que lo que explicaría la prevalencia y distribución de ambas. Los medicamentos que actúan sobre el sistema renina-angiotensina-aldosterona, son pilares básicos en el manejo de estas enfermedades. Se sabe de tiempo atrás que estos fármacos aumentan en forma significativa la expresión en el tejido pulmonar de receptores para la enzima de conversión de angiotensina de tipo 2. Este hecho junto con el conocimiento de que la vía de entrada del virus a la célula es precisamente el receptor de ECA-2, inició una hipótesis, basada en evidencia de muy baja calidad, que rápidamente se generalizó en los medios de comunicación, de que el empleo de estos medicamentos podría ser negativo y que deberían suspenderse. La respuesta de prácticamente todas las sociedades científicas fue casi inmediata, con la indicación precisa de que no debería suspenderse el tratamiento con estos fármacos, puesto que la evidencia de su utilidad está basada en una evidencia muy sólida y de gran calidad. Casi simultáneamente también apareció la hipótesis, también basada en evidencia muy preliminar, de que estos medicamentos no solo resultan dañinos sino que son benéficos, tampoco se aceptan todavía como agentes para la prevención o tratamiento de esta enfermedad o sus complicaciones. La presente revisión relata los conocimientos actuales sobre la relación entre COVID-19 y SRAA.

Abstract The COVID-19 pandemic has had major negative health, psychological, social and economic repercussions for individuals, families, communities, countries and for humanity in general. The interrelation with age and the presence of chronic non-communicable diseases (hypertension, diabetes, obesity, smoking) seems to go further than what would be explained by the prevalence and distribution of both. The drugs that act on the renin-angiotensin-aldosterone system are in many cases the backbone for the management of these diseases, it has been known for a long time that these drugs significantly increase the expression of receptors for angiotensin conversion enzyme type 2 in the lung tissue. This fact, together with the knowledge that the route of entry of the virus into the cell is precisely the ACE-2 receptor, initiated a hypothesis, based on very low-quality evidence, which quickly became generalized in the media, that the use of these drugs could be negative and that they should be interrupted immediately. The response of practically all Scientific Societies was almost immediate, with the precise indication that treatment with these drugs should not be discontinued, since the evidence of their usefulness is based on very solid and high-quality evidence. Simultaneously, a different hypothesis also appeared, also based on very preliminary evidence, that these drugs are not only harmful but also beneficial, however these medicaments are not yet accepted as agents for the prevention or treatment of this disease or its complications. This review reports current knowledge on the relationship between COVID-19 and SRAA.

Hibiscus Acid and Chromatographic Fractions from Hibiscus Sabdariffa Calyces: Antimicrobial Activity against Multidrug-Resistant Pathogenic Bacteria.

The anti-microbial properties of acetone extracts from Hibiscus sabdariffa calyces, fractions isolated by silica gel chromatography and hibiscus acid purified from some of these fractions and additionally identified by nuclear magnetic resonance spectroscopy, mid-infrared spectroscopy and X-ray diffraction, were studied against both multidrug-resistant Salmonella strains and pathogenic Escherichia coli bacteria. Gel diffusion was used to determine the anti-microbial effects. The mode of action of hibiscus acid was determined by crystal violet assay. Hibiscus acid and 17 of the 25 chromatographic fractions obtained, displayed an anti-microbial effect against all bacterial strains tested. Hibiscus acid showed a greater anti-microbial effect than the acetone extract against most of the bacteria strains, while chromatographic fractions IX-XIV exerted the greatest anti-microbial effect against all bacteria. The minimum inhibitory concentration of the acetone extract was 7 mg/mL, and the minimum bactericidal concentration was 10 mg/mL, while the corresponding values for hibiscus acid were 4-7 and 7 mg/mL, respectively. The results of the crystal violet assay indicate that hibiscus acid alters membrane permeability. Hibiscus acid is a potential alternative to control multidrug-resistant bacteria. Due to its ready availability and easy extraction from H. sabdariffa, hibiscus acid is potentially useful in the food industries.

Inactivation of the quorum-sensing transcriptional regulators LasR or RhlR does not suppress the expression of virulence factors and the virulence of Pseudomonas aeruginosa PAO1.

Pseudomonas aeruginosa is an environmental bacterium but is also an opportunistic pathogen. The aim of this work is to evaluate the contribution of P. aeruginosa LasR and RhlR transcriptional regulators of the quorum-sensing response (QSR) to the production of virulence factors, and to its virulence in a mouse abscess model. The QSR is a complex regulatory network that modulates the expression of several virulence factors, including elastase, pyocyanin and rhamnolipids. LasR, when complexed with the auto-inducer 3-oxo-dodecanoyl lactone (3O-C12-HSL), produced by LasI, is at the top of the QSR regulatory cascade since it activates transcription of some genes encoding virulence factors (such as the gene coding for elastase, lasB) and also transcription of both rhlR and rhlI, encoding the synthase of the auto-inducer butanoyl-homoserine lactone (C4-HSL). In turn RhlR, coupled with C4-HSL, activates the transcription of genes encoding for the enzymes involved in pyocyanin and rhamnolipid production. Several efforts have been made to obtain inhibitors of LasR activity that would suppress the QSR. However, these attempts have used chemical compounds that might not be specific for LasR inactivation. In this work we show that individual inactivation of either lasR or rhlR did not block the QSR, nor did it impair P. aeruginosa virulence, and that even a lasR rhlR double mutant still presented residual virulence, even lacking the production of virulence factors. These results show that the inhibition of either lasR or rhlR is not a straightforward approach to blocking P. aeruginosa virulence, due to the great complexity of the QSR.

[Cervical cryosurgery: thousand cases report]. / Criocirugía cervical: reporte de mil casos.

BACKGROUND: Treatments for cervical lesions through the years have been varied, from cauterization with chemicals, to the use of electrosurgery with diathermic loop, however the method to be chosen should be one that offers greater benefits and lower risks. OBJECTIVE: Present a well structured study protocol in patients presenting with cervical disease and offer treatment cryotherapy as ablative method of choice in this group of patients and returning this widely known process, but nevertheless had been relegated. MATERIAL AND METHOD: By an analytical and descriptive retrospective study and treatment of one thousand patients with cervical pathology in the course of 20 years, in which in addition to the drug treatment of individual patients, treatment was performed as ablative cryosurgery cervical is reported, having obtained very good results. RESULTS: With ablative treatment indicated the problem of all' patients resolved, having had a very satisfactory in the short, medium and long term, have had no significant morbidity, thus fulfilling the stated objective. CONCLUSION: Research carried out shows that the surgical procedure performed in carefully selected patients with cervical pathology coursing was appropriate because the results thus demonstrated.

[Transcervical myomectomy and uterine fibroids: report of ten cases]. / Miomatosis uterina y miomectomía transcervical. Reporte de diez casos.

BACKGROUND: Uterine fibroids are the most common tumors of the uterus, their distribution in anatomical layers and segments of it are very varied clinical manifestations are usually abnormal bleeding and known treatments, the surgery is the most accomplished, either myomectomy or hysterectomy by both endoscopy and laparotomy, transvaginal approach is less common, but consider it a right way and solving the problem in selected cases. OBJECTIVE: To present a well-defined study protocol in patients with abnormal uterine bleeding, and myomectomy as a surgical transcervical simple, safe and effective in patients with intracavitary myoma protruded through the cervical canal. MATERIAL AND METHODS: ten patients are presented with abnormal uterine bleeding and anemia of various degrees, studied over a period of two years, following a research protocol for clinical methods, cabinet and laboratory diagnosis was submucosal fibroids with single fibroid, pedunculated protruding a vagina, treatment was performed transcervical myomectomy. RESULTS: The surgical procedure was obtained by solving the problem, having found the ten patients in the subsequent revisions in the outpatient, asymptomatic and without tumor lesions in the uterus. CONCLUSIONS: This study shows that performing a notarization in patients with abnormal uterine bleeding and making appropriate surgical treatment, achieves the desired objectives.

[Growth and mortality of the mollusk Pteria sterna in wild banks of Southern Baja California, Mexico]. / Crecimiento y mortalidad de la concha nácar Pteria sterna en bancos silvestres de Baja California Sur, México.

The Gulf of California nacre shell Pteria sterna is an important marine resource in Mexico, and the main species for "half" and round pearl production in the American continent. Wild spat can only be extracted legally for research or culture activities. This study calculates growth and mortality parameters for wild stocks in the eastern coast of Southern Baja California. Height's data (353 dorso-ventral measurements) were taken from 1997 to 1999 at Santa Rosalia, Mulegé and Loreto Bay coast. The maximum length was estimated at 130.35 mm (124.22-136.48 mm, p>0.95). The length frequency data were set in a "virtual year". Seasonal von Bertalanffy growth parameters were calculated in the ELEFAN I routine, the values are: L(infinity) = 156.02 mm, k = 0.48 year(-1), t0 = -0.216 years, C = 0.43, WP = 0.73. and t(s) = 0.5. The growth performance index was phi' = 4.068. The total mortality was calculated from length-converted catch curve Z = 3.34 year(-1). The length-weight relationship was fixed for the equation W = 0.000756 * L(i)(2.7075) (r2 = 0.90, n = 233). The growth parameters values in experimental repopulation conditions are quite different, in contrast with the growth estimated in wild stocks oysters. The value of total mortality is similar to the estimations for Pinctada fucata populations from the Red Sea and P. radiata from the Mediterranean Sea.

Crecimiento y mortalidad de la concha nácar Pteria sterna en bancos silvestres de Baja California Sur, México

Growht and mortality of the mollusk Pteria sterna in wild banks of Southern Baja California, Mexico. The Gulf of California nacre shell Pteria sterna is an important marine resource in Mexico, and the main species for "half" and round pearl production in the American continent. Wild spat can only be extracted legally for research or culture activities. This study calculates growth and mortality parameters for wild stocks in the eastern coast of Southern Baja California. Height’s data (353 dorso-ventral measurements) were taken from 1997 to 1999 at Santa Rosalía, Mulegé and Loreto Bay coast. The maximum length was estimated at 130.35 mm (124.22-136.48 mm, p>0.95). The length frequency data were set in a "virtual year". Seasonal von Bertalanffy growth parameters were calculated in the ELEFAN I routine, the values are: L∞ = 156.02 mm, k = 0.48 year-1, t0 = -0.216 years, C = 0.43, WP = 0.73. and t s = 0.5. The growth performance index was Φ’ = 4.068. The total mortality was calculated from length-converted catch curve Z = 3.34 year-1. The length-weight relationship was fixed for the equation W = 0.000756 * L(i)2.7075 (r²= 0.90, n = 233). The growth parameters values in experimental repopulation conditions are quite different, in contrast with the growth estimated in wild stocks oysters. The value of total mortality is similar to the estimations for Pinctada fucata populations from the Red Sea and P. radiata from the Mediterranean Sea. Rev. Biol. Trop. 57 (3): 659-670. Epub 2009 September 30.

La concha nácar Pteria sterna sustenta los perlicultivos en México, y es la base de producción de perlas en el continente Americano. Está bajo protección especial desde 1994, y solo puede capturarse semilla natural para cultivo e investigación. Determinamos su crecimiento y mortalidad en bancos silvestres, registrando la altura de ostras de Santa Rosalía, Mulegé y Bahía de Loreto (1997-99). La longitud máxima estimada fue 130.35 mm (124.22-136.48 mm, P>0.95). Las frecuencias de longitudes se ordenaron en un "año virtual" (Guanco 1991). Los parámetros de crecimiento de von Bertalanffy estimados con el programa ELEFAN I fueron: L∞= 156.02 mm, k=0.48año-1, t0=-0.216 años, C= 0.43 y WP = 0.73; el índice de desempeño de crecimiento fue Φ’ = 4.068. La mortalidad total fue de Z = 3.34 año -1por longitud convertida a curva de captura. La regresión del peso total y la altura tuvo la expresión W = 0.000756 * L(i)2.7075 (r²=0.90, n=233). Mostramos la diferencia entre los parámetros de crecimiento en condiciones de repoblamiento experimental y aquellos de individuos silvestres de P. sterna. El valor de mortalidad total es comparable a aquellos de Pinctada fucata en el mar Rojo o P. radiata en el mar Mediterráneo.

[Growth and mortality of the mother-of-pearl Pinctada mazatlanica in natural populations of the east coast of Baja California Sur, Mexico]. / Crecimiento y mortalidad de la madreperla Pinctada mazatlanica en poblaciones naturales del litoral oriental de Baja California Sur, México.

The Mexican Pacific mother-of-pearl Pinctada mazatlanica was placed in forbidden fisheries status for the Mexican Federal Government and considered in extinction danger since 1939. This decree was modified in 1994 to allow the capture of spat for research or marine culture. We estimated the growth and mortality of mother-of-pearl from the eastern littoral of South Baja California wild stock in the periods 1992-93 and 1997-99. We used 38 sample stations at 2 bays and 6 insular complexes. The maximum length was 187.22 mm (179.83-195.81 mm, P > 0.95). Seasonal von Bertalanffy growth (ELEFAN I routine) values are: L(infinity) = 193.31 mm, k = 0.54 year(-1), t(0) = -0.1805 year, C = 0.49 and WP = 0.75. The growth performance index was Phi' = 4.305. The total mortality was calculated from a length-converted catch curve Z = 2.03 año(-1). Length-weight relationship W(i) = 0.0005418 * L(i)(2.7301). The growth parameters were similar to those for Pinctada margaritifera var. cumingi (open ocean wild stocks). The wild stock oysters differ from culture individuals at experimental repopulation conditions in Paz Bay. The total mortality is similar to that for Pinctada radiata in the Red Sea.

Crecimiento y mortalidad de la madreperla Pinctada mazatlanica en poblaciones naturales del litoral oriental de Baja California Sur, México

Growth and mortality of the mother-of-pearl Pinctada mazatlanica in natural populations of the east coast of Baja California Sur, Mexico. The Mexican Pacific mother-of-pearl Pinctada mazatlanica was placed in forbidden fisheries status for the Mexican Federal Government and considered in extinction danger since 1939. This decree was modified in 1994 to allow the capture of spat for research or marine culture. We estimated the growth and mortality of mother-of-pearl from the eastern littoral of South Baja California wild stock in the periods 1992-93 and 1997-99. We used 38 sample stations at 2 bays and 6 insular complexes. The maximum length was 187.22 mm (179.83-195.81 mm, P > 0.95). Seasonal von Bertalanffy growth (ELEFAN I routine) values are: = 193.31 mm, k = 0.54 year-1, t0 = -0.1805 year, C = 0.49 and WP = 0.75. The growth performance index was ’ = 4.305. The total mortality was calculated from a length-converted catch curve Z = 2.03 año-1. Length-weight relationship W(i) = 0.0005418 * L(i)2.7301. The growth parameters were similar to those for Pinctada margaritifera var. cumingi (open ocean wild stocks). The wild stock oysters differ from culture individuals at experimental repopulation conditions in Paz Bay. The total mortality is similar to that for Pinctada radiata in the Red Sea. Rev. Biol. Trop. 57 (1-2): 53-61. Epub 2009 June 30.

La madreperla Pinctada mazatlanica esta en veda desde 1939 y considerada en peligro de extinción, cambiando su categoría a protección especial en 1994. El presente estudio estima su crecimiento y mortalidad en bancos naturales en el periodo 1992-93 y 1997-99. Se registró el alto de la concha de ostras en poblaciones desde el paralelo 28º a 23º LN del litoral oriental de Baja California Sur, abarcando 38 estaciones, 2 bahías y 6 islas. La longitud máxima estimada fue 187.22mm (179.83-195.81mm, P > 0.95). Las frecuencias de longitud se ordenaron en un "año virtual". Los parámetros de crecimiento de von Bertalanffy estimados con el programa ELEFAN I fueron: o = 193.31mm, k=0.54año-1, t0= -0.1805 años, C=0.49 y WP=0.75; el índice de desempeño del crecimiento fue’=4.305. La mortalidad total fue de Z=2.03 año-1 por longitud convertida a curva de captura. La regresión peso total y la altura tuvo la expresión W(i)=0.0005418 * L(i)2.7301. Los parámetros de crecimiento fueron similares a los de Pinctada margaritifera de bancos de mar abierto y diferentes a aquellos de ostras perleras en repoblamiento en bahía de La Paz. La mortalidad mostró valores parecidos a los estimados para Pinctada radiata del Mar Rojo.