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Universidad de Ciencias Medicas

UniversitySan José, Costa Rica

Research output, citation impact, and the most-cited recent papers from Universidad de Ciencias Medicas (Costa Rica). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
11.9K
Citations
31.8K
h-index
60
i10-index
556
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Universidad de Ciencias Medicas

Top-cited papers from Universidad de Ciencias Medicas

Consensus guidelines for the detection of immunogenic cell death
Oliver Kepp, Laura Senovilla, Ilio Vitale, Erika Vacchelli +4 more
2014· OncoImmunology821doi:10.4161/21624011.2014.955691

and to screen large chemical libraries for putative ICD inducers, based on a high-content, high-throughput platform that we recently developed. Such a platform allows for the detection of multiple DAMPs, like cell surface-exposed calreticulin, extracellular ATP and high mobility group box 1 (HMGB1), and/or the processes that underlie their emission, such as endoplasmic reticulum stress, autophagy and necrotic plasma membrane permeabilization. We surmise that this technology will facilitate the development of next-generation anticancer regimens, which kill malignant cells and simultaneously convert them into a cancer-specific therapeutic vaccine.

Virulence factors of the<i>Mycobacterium tuberculosis</i>complex
Marina Andrea Forrellad, Laura Inés Klepp, Andrea Gioffré, Julia Sabio y García +4 more
2013· Virulence606doi:10.4161/viru.22329

The Mycobacterium tuberculosis complex (MTBC) consists of closely related species that cause tuberculosis in both humans and animals. This illness, still today, remains to be one of the leading causes of morbidity and mortality throughout the world. The mycobacteria enter the host by air, and, once in the lungs, are phagocytated by macrophages. This may lead to the rapid elimination of the bacillus or to the triggering of an active tuberculosis infection. A large number of different virulence factors have evolved in MTBC members as a response to the host immune reaction. The aim of this review is to describe the bacterial genes/proteins that are essential for the virulence of MTBC species, and that have been demonstrated in an in vivo model of infection. Knowledge of MTBC virulence factors is essential for the development of new vaccines and drugs to help manage the disease toward an increasingly more tuberculosis-free world.

The actin cytoskeleton participates in the early events of autophagosome formation upon starvation induced autophagy
Milton Osmar Aguilera, Walter Berón, María Isabel Colombo
2012· Autophagy163doi:10.4161/auto.21459

Autophagy is a process by which cytoplasmic material is sequestered in a double-membrane vesicle destined for degradation. Nutrient deprivation stimulates the pathway and the number of autophagosomes in the cell increases in response to such stimulus. In the current report we have demonstrated that actin is necessary for starvation-mediated autophagy. When the actin cytoskeleton is depolymerized, the increase in autophagic vacuoles in response to the starvation stimulus was abolished without affecting maturation of remaining autophagosomes. In addition, actin filaments colocalized with ATG14, BECN1/Beclin1 and PtdIns3P-rich structures, and some of them have a typical omegasome shape stained with the double FYVE domain or ZFYVE1/DFCP1. In contrast, no major colocalization between actin and ULK1, ULK2, ATG5 or MAP1LC3/LC3 was observed. Taken together, our data indicate that actin has a role at very early stages of autophagosome formation linked to the PtdIns3P generation step. In addition, we have found that two members of the Rho family of proteins, RHOA and RAC1 have a regulatory function on starvation-mediated autophagy, but with opposite roles. Indeed, RHOA has an activatory role whereas Rac has an inhibitory one. We have also found that inhibition of the RHOA effector ROCK impaired the starvation-mediated autophagic response. We propose that actin participates in the initial membrane remodeling stage when cells require an enhanced rate of autophagosome formation, and this actin function would be tightly regulated by different members of the Rho family.

Autophagy in protists
Michael Duszenko, Michael L. Ginger, Ana Brennand, Melisa Gualdrón‐López +4 more
2011· Autophagy158doi:10.4161/auto.7.2.13310

Autophagy is the degradative process by which eukaryotic cells digest their own components using acid hydrolases within the lysosome. Originally thought to function almost exclusively in providing starving cells with nutrients taken from their own cellular constituents, autophagy is in fact involved in numerous cellular events including differentiation, turnover of macromolecules and organelles, and defense against parasitic invaders. During the last 10-20 years, molecular components of the autophagic machinery have been discovered, revealing a complex interactome of proteins and lipids, which, in a concerted way, induce membrane formation to engulf cellular material and target it for lysosomal degradation. Here, our emphasis is autophagy in protists. We discuss experimental and genomic data indicating that the canonical autophagy machinery characterized in animals and fungi appeared prior to the radiation of major eukaryotic lineages. Moreover, we describe how comparative bioinformatics revealed that this canonical machinery has been subject to moderation, outright loss or elaboration on multiple occasions in protist lineages, most probably as a consequence of diverse lifestyle adaptations. We also review experimental studies illustrating how several pathogenic protists either utilize autophagy mechanisms or manipulate host-cell autophagy in order to establish or maintain infection within a host. The essentiality of autophagy for the pathogenicity of many parasites, and the unique features of some of the autophagy-related proteins involved, suggest possible new targets for drug discovery. Further studies of the molecular details of autophagy in protists will undoubtedly enhance our understanding of the diversity and complexity of this cellular phenomenon and the opportunities it offers as a drug target.

Age at menopause in Latin America
Juan E. Blümel, Peter Chedraui, Andrés Calle, Roberto Bocanera +4 more
2006· Menopause The Journal of The North American Menopause Society154doi:10.1097/01.gme.0000227338.73738.2d

In Brief Objective: To assess the age at menopause (AM) in Latin America urban areas. Design: A total of 17,150 healthy women, aged 40 to 59 years, accompanying patients to healthcare centers in 47 cities of 15 Latin American countries, were surveyed regarding their age, educational level, healthcare coverage, history of gynecological surgery, smoking habit, presence of menses, and the use of contraception or hormone therapy at menopause. The AM was calculated using logit analysis. Results: The mean age of the entire sample was 49.4 ± 5.5 years. Mean educational level was 9.9 ± 4.5 years, and the use of hormone therapy and oral contraception was 22.1% and 7.9%, respectively. The median AM of women in all centers was 48.6 years, ranging from 43.8 years in Asuncion (Paraguay) to 53 years in Cartagena de Indias (Colombia). Logistic regression analysis determined that women aged 49 living in cities at 2,000 meters or more above sea level (OR = 2.0, 95% CI: 1.4-2.9, P < 0.001) and those with lower educational level (OR = 1.9, 95% CI: 1.3-2.8, P < 0.001) or living in countries with low gross national product (OR = 2.1, 95% CI: 1.5-2.9, P < 0.001) were more prone to an earlier onset of menopause. Conclusions: The AM varies widely in Latin America. Lower income and related poverty conditions influence the onset of menopause. To avoid biases, logit analysis has been used to calculate the age at menopause as the percentage of women in amenorrhea at different ages. The major factors that increase the risk of an earlier age at menopause were living at altitudes above 2,000 meters and low socioeconomic and educational level.

Ventricular repolarization markers for predicting malignant arrhythmias in clinical practice
Yaniel Castro Torres
2015· World Journal of Clinical Cases152doi:10.12998/wjcc.v3.i8.705

Malignant cardiac arrhythmias which result in sudden cardiac death may be present in individuals apparently healthy or be associated with other medical conditions. The way to predict their appearance represents a challenge for the medical community due to the tragic outcomes in most cases. In the last two decades some ventricular repolarization (VR) markers have been found to be useful to predict malignant cardiac arrhythmias in several clinical conditions. The corrected QT, QT dispersion, Tpeak-Tend, Tpeak-Tend dispersion and Tp-e/QT have been studied and implemented in clinical practice for this purpose. These markers are obtained from 12 lead surface electrocardiogram. In this review we discuss how these markers have demonstrated to be effective to predict malignant arrhythmias in medical conditions such as long and short QT syndromes, Brugada syndrome, early repolarization syndrome, acute myocardial ischemia, heart failure, hypertension, diabetes mellitus, obesity and highly trained athletes. Also the main pathophysiological mechanisms that explain the arrhythmogenic predisposition in these diseases and the basis for the VR markers are discussed. However, the same results have not been found in all conditions. Further studies are needed to reach a global consensus in order to incorporate these VR parameters in risk stratification of these patients.

Effects of Romosozumab Compared With Teriparatide on Bone Density and Mass at the Spine and Hip in Postmenopausal Women With Low Bone Mass
Harry K. Genant, Klaus Engelke, Michael A. Bolognese, C. Mautalén +4 more
2016· Journal of Bone and Mineral Research141doi:10.1002/jbmr.2932

ABSTRACT Romosozumab, a monoclonal antibody that binds sclerostin, has a dual effect on bone by increasing bone formation and reducing bone resorption, and thus has favorable effects in both aspects of bone volume regulation. In a phase 2 study, romosozumab increased areal BMD at the lumbar spine and total hip as measured by DXA compared with placebo, alendronate, and teriparatide in postmenopausal women with low bone mass. In additional analyses from this international, randomized study, we now describe the effect of romosozumab on lumbar spine and hip volumetric BMD (vBMD) and BMC at month 12 as assessed by QCT in the subset of participants receiving placebo, s.c. teriparatide (20 µg once daily), and s.c. romosozumab (210 mg once monthly). QCT measurements were performed at the lumbar spine (mean of L1 and L2 entire vertebral bodies, excluding posterior processes) and hip. One year of treatment with romosozumab significantly increased integral vBMD and BMC at the lumbar spine and total hip from baseline, and compared with placebo and teriparatide (all p &amp;lt; 0.05). Trabecular vertebral vBMD improved significantly and similarly from baseline (p &amp;lt; 0.05) with both romosozumab (18.3%) and teriparatide (20.1%), whereas cortical vertebral vBMD gains were larger with romosozumab compared with teriparatide (13.7% versus 5.7%, p &amp;lt; 0.0001). Trabecular hip vBMD gains were significantly larger with romosozumab than with teriparatide (10.8% versus 4.2%, p = 0.01), but were similar for cortical vBMD (1.1% versus –0.9%, p = 0.12). Cortical BMC gains were larger with romosozumab compared with teriparatide at both the spine (23.3% versus 10.9%, p &amp;lt; 0.0001) and hip (3.4% versus 0.0%, p = 0.03). These improvements are expected to result in strength gains and support the continued clinical investigation of romosozumab as a potential therapy to rapidly reduce fracture risk in ongoing phase 3 studies. © 2016 American Society for Bone and Mineral Research.

Artificial Intelligence: A New Paradigm in Obstetrics and Gynecology Research and Clinical Practice
Pulwasha Maria Iftikhar, Marcela V. Kuijpers, Azadeh Khayyat, Aqsa Iftikhar +1 more
2020· Cureus126doi:10.7759/cureus.7124

Artificial intelligence (AI) is growing exponentially in various fields, including medicine. This paper reviews the pertinent aspects of AI in obstetrics and gynecology (OB/GYN) and how these can be applied to improve patient outcomes and reduce the healthcare costs and workload for clinicians. Herein, we will address current AI uses in OB/GYN, and the use of AI as a tool to interpret fetal heart rate (FHR) and cardiotocography (CTG) to aid in the detection of preterm labor, pregnancy complications, and review discrepancies in its interpretation between clinicians to reduce maternal and infant morbidity and mortality. AI systems can be used as tools to create algorithms identifying asymptomatic women with short cervical length who are at risk of preterm birth. Additionally, the benefits of using the vast data capacity of AI storage can assist in determining the risk factors for preterm labor using multiomics and extensive genomic data. In the field of gynecological surgery, the use of augmented reality helps surgeons detect vital structures, thus decreasing complications, reducing operative time, and helping surgeons in training to practice in a realistic setting. Using three-dimensional (3D) printers can provide materials that mimic real tissues and also helps trainees to practice on a realistic model. Furthermore, 3D imaging allows better depth perception than its two-dimensional (2D) counterpart, allowing the surgeon to create preoperative plans according to tissue depth and dimensions. Although AI has some limitations, this new technology can improve the prognosis and management of patients, reduce healthcare costs, and help OB/GYN practitioners to reduce their workload and increase their efficiency and accuracy by incorporating AI systems into their daily practice. AI has the potential to guide practitioners in decision-making, reaching a diagnosis, and improving case management. It can reduce healthcare costs by decreasing medical errors and providing more dependable predictions. AI systems can accurately provide information on the large array of patients in clinical settings, although more robust data is required.

Yeast diversity in the oral microbiota of subjects with periodontitis:<i>Candida albicans</i>and<i>Candida dubliniensis</i>colonize the periodontal pockets
Blanca Urzúa, Gabriel Hermosilla, Jorge Gamonal, Irene Morales‐Bozo +4 more
2008· Medical Mycology119doi:10.1080/13693780802060899

The term periodontitis encompasses several polymicrobial infectious diseases, of multifactorial etiology, with chronic and aggressive forms. In spite of the etiopathogenic differences between these two forms of the disease, few studies have analyzed the subgingival colonization by yeast. The objective of this investigation was to analyze the composition of the yeast microbiota present in the mucosa and subgingival sites of healthy individuals and patients with aggressive and chronic periodontitis. For this, samples were recovered from these two locations and the yeast recovered identified by phenotypic and genotypic methods. Patients with chronic periodontitis showed significant differences in relation to the other groups with respect to carrier status (69.2% versus 35.7% of healthy individuals; [chi(i)(2) test; p=0.014]), the total number of isolated colony forming units or CFU (mean and ranges 281.6 (0-6048) [K-W(2)=6.998; p=0.03]), the Simpson diversity index (I) in site b (I(b)=0.344 versus healthy subjet and aggresive periodontitis where I=0 [multiple t-test comparisons with the Bonferronni correction, p<0.05]), and the species profile. Interestingly, in spite of the varied profiles of the species present in the mucosa of the three groups analyzed we noted that only C. albicans and C. dubliniensis were capable of colonizing the periodontal pockets in patients with chronic periodontitis, while only C. albicans was identified in the subgingiva of healthy individuals and patients with aggressive periodontitis.

Emergence of Penicillin‐Nonsusceptible<i>Streptococcus pneumoniae</i>Clones Expressing Serotypes Not Present in the Antipneumococcal Conjugate Vaccine
Nurith Porat, Adriano Arguedas, Brian G. Spratt, Ronit Trefler +4 more
2004· The Journal of Infectious Diseases114doi:10.1086/425908

BACKGROUND: Penicillin-nonsusceptible Streptococcus pneumoniae isolates are confined mainly to a few serogroups. Capsular transformation may serve as a mechanism for spreading antibiotic resistance to new serotypes. METHODS: Antibiogram and molecular typing, by pulsed-field gel electrophoresis (PFGE), were performed on 46 nasopharyngeal and middle ear fluid (MEF) isolates expressing serotype 11A, 45 MEF isolates expressing serotype 15B/C (recovered during 1998-2003 from Israeli children <5 years old), and 57 MEF isolates expressing serotype 19F (recovered during 1998-2001 from Costa Rican children <7.5 years old). RESULTS: PFGE patterns showed that 49 (86%) of 57 serotype 19F isolates and 19 (41%) of 46 serotype 15B/C isolates were closely related. The vast majority of these isolates (80% of serotype 19F and 100% of serotype 15B/C isolates) were nonsusceptible to penicillin. Multilocus sequence typing (MLST) data show that the serotype 15B/C isolates belonged to the ST346 cluster, whereas the serotype 19F isolates were a single-locus variant of ST346. For serotype 11A isolates, PFGE patterns and MLST analysis showed that 8 (80%) of the 10 penicillin-nonsusceptible isolates belonged to a single clone--namely, ST156--which was identical to the international Spain9V-3 clone. CONCLUSIONS: Penicillin-nonsusceptible pneumococcal clones of serotypes not related to those included in the 11-valent conjugate vaccines may derive from capsular transformation of vaccine-related serotypes. Of particular concern was the detection of serotype 11A variants of the successful international Spain9V-3 clone. This phenomenon, although seemingly rare at present, can have implications for the long-term effectiveness of the conjugate vaccines.

Comparative Safety Profile of Levofloxacin in 2523 Children With a Focus on Four Specific Musculoskeletal Disorders
Gary J. Noel, John S. Bradley, Ralph E. Kauffman, Ciarán M. Duffy +4 more
2007· The Pediatric Infectious Disease Journal103doi:10.1097/inf.0b013e3180cbd382

BACKGROUND: Fluoroquinolones, including levofloxacin, have not been recommended for use in children largely because studies in juvenile laboratory animals suggest there may be an increased risk of fluoroquinolone-associated cartilage lesions. A large prospective trial is needed to assess the risks associated with using levofloxacin in children. OBJECTIVE: Assess the safety and tolerability of levofloxacin therapy in children based on observations for 1 year after therapy. METHODS: Safety data were collected in children who participated in 1 of 3 efficacy trials (N = 2523) and a subset of these children who also subsequently participated in a long-term 1-year surveillance trial (N = 2233). Incidence of adverse events in children randomized to receive levofloxacin versus nonfluoroquinolone antibiotics was compared. Based on assessments by treating physicians and an independent data safety monitoring committee, events related to the musculoskeletal system were further categorized as 1 of 4 predefined musculoskeletal disorders (arthralgia, arthritis, tendinopathy, gait abnormality) considered most likely clinical correlates of fluoroquinolone-associated cartilage lesions observed in laboratory animals. RESULTS: Levofloxacin was well tolerated during and for 1 month after therapy as evidenced by similar incidence and character of adverse events compared with nonfluoroquinolone antibiotics. However, incidence of at least 1 of the 4 predefined musculoskeletal disorders (largely due to reports of arthralgia) was greater in levofloxacin-treated compared with nonfluoroquinolone-treated children at 2 months (2.1% vs. 0.9%; P = 0.04) and 12 months (3.4% vs. 1.8%; P = 0.03) after starting therapy. CONCLUSIONS: The incidence of 1 or more of the 4 predefined musculoskeletal disorders identified in nonblinded, prospective evaluations, was statistically greater in levofloxacin-treated compared with comparator-treated children.

Regression of calcinosis during diltiazem treatment in juvenile dermatomyositis.
Beatriz Oliveri, Roberto Palermo, C. Mautalén, O Hübscher
1996· PubMed95

An 8-year-old girl with juvenile dermatomyositis (DM) developed dystrophic calcifications 26 months after diagnosis. She also had severe steroid induced bone loss (osteoporosis). The calcifications turned into generalized heterotopic calcinosis with an exoskeleton-like pattern, despite successful treatment of her myopathy with methylprednisolone and immunosuppressive drugs. She was subsequently treated with oral diltiazem (5 mg/kg/day) to control calcinosis and oral pamidronate (4 mg/kg/day) in addition to calcium and vitamin D supplementation, which she had been taking for 3 years. After 21 months of treatment, clinical and radiological examination revealed dramatic regression of the calcinosis. Bone mass reached normal levels, as determined by bone absorptiometry. Diltiazem alone or in combination with other drugs could be a useful therapy in patients with juvenile DM and pronounced calcifications.

ATP is released from autophagic vesicles to the extracellular space in a VAMP7-dependent manner
Claudio M. Fader, Milton Osmar Aguilera, María Isabel Colombo
2012· Autophagy86doi:10.4161/auto.21858

Autophagy is a normal degradative pathway that involves the sequestration of cytoplasmic components and organelles in a vacuole called autophagosome. SNAREs proteins are key molecules of the vesicle fusion machinery. Our results indicate that in a mammalian tumor cell line a subset of VAMP7 (V-SNARE)-positive vacuoles colocalize with LC3 at the cell periphery (focal adhesions) upon starvation. The re-distribution of VAMP7 positive structures is a microtubule-dependent event, with the participation of the motor protein KIF5 and the RAB7 effector RILP. Interestingly, most of the VAMP7-labeled vesicles were loaded with ATP. Moreover, in cells subjected to starvation, these structures fuse with the plasma membrane to release the nucleotide to the extracellular medium. Summarizing, our results show the molecular components involved in the release of ATP to extracellular space, which is recognized as an important autocrine/paracrine signal molecule that participates in the regulation of several cellular functions such as immunogenicity of cancer cell death or inflammation.

Comparative Study of Levofloxacin in the Treatment of Children With Community-Acquired Pneumonia
John S. Bradley, Adriano Arguedas, Jeffrey L. Blumer, Xavier Sáez‐Llorens +2 more
2007· The Pediatric Infectious Disease Journal85doi:10.1097/inf.0b013e3180cbd2c7

BACKGROUND: Levofloxacin has established efficacy and safety in the treatment of community-acquired pneumonia (CAP) in adults, and its use as an alternative therapy for children with CAP has been proposed. OBJECTIVE: Assess the clinical efficacy and safety of levofloxacin compared with standard of care antibiotic therapy in the treatment of CAP in children aged 6 months to 16 years. METHODS: In an open-label, multicenter, noninferiority trial, children with CAP were randomized 3:1 to receive levofloxacin or comparator antimicrobial therapy (0.5 to <5 years: amoxicillin/clavulanate or ceftriaxone; > or =5 years: clarithromycin or ceftriaxone with clarithromycin or erythromycin lactobinate) for 10 days. The primary outcome was cure rates at the test-of-cure visit (10-17 days after completing treatment) as determined by symptoms, physical examination, and chest radiography. RESULTS: Seven hundred and thirty-eight children were enrolled and 539 (405 levofloxacin-treated, 134 comparator-treated) were clinically evaluable at test-of-cure visit. Clinical cure rates were 94.3% (382 of 405) in levofloxacin-treated and 94.0% (126 of 134) in comparator-treated children. Cure rates were also similar for levofloxacin and comparator for each age group (<5 years, 92.2% versus 90.8%; > or =5 years, 96.5% versus 97.1%; respectively) and for children categorized as being at higher risk for severe disease. Mycoplasma pneumoniae was the most frequently identified cause of pneumonia (230 children). Levofloxacin was as well tolerated as comparators, with similar type and incidence of adverse events. CONCLUSIONS: Levofloxacin was as well tolerated and effective as standard-of-care antibiotics for the treatment of CAP in infants and children.

An overview of resistance to chemotherapy in osteosarcoma and future perspectives
Dorian Yarih García-Ortega, Sara Aileen Cabrera-Nieto, Haydee Sarai Caro-Sánchez, Marlid Cruz‐Ramos
2022· Cancer Drug Resistance73doi:10.20517/cdr.2022.18

Osteosarcoma (OS) is the most common type of bone sarcoma. Despite the availability of multimodal treatment with surgery and chemotherapy, the clinical results remain unsatisfactory. The main reason for the poor outcomes in patients with OS is the development of resistance to methotrexate, cisplatin, doxorubicin, and ifosfamide. Molecular and cellular mechanisms associated with resistance to chemotherapy include DNA repair and cell-cycle alterations, enhanced drug efflux, increased detoxification, resistance to apoptosis, autophagy, tumor extracellular matrix, and angiogenesis. This versatility of cells to generate chemoresistance has motivated the use of anti-angiogenic therapy based on tyrosine kinase inhibitors. This approach has shown that other therapies, along with standard chemotherapy, can improve responses to therapy in patients with OS. Moreover, microRNAs may act as predictors of drug resistance in OS. This review provides insight into the molecular and cellular mechanisms involved in the development of resistance during the treatment of OS and discusses promising novel therapies (e.g., afatinib and palbociclib) for overcoming resistance to chemotherapy in OS.

Pacific ciguatoxin‐1b effect over Na<sup>+</sup> and K<sup>+</sup> currents, inositol 1,4,5‐triphosphate content and intracellular Ca<sup>2+</sup> signals in cultured rat myotubes
Jorge Hidalgo, José Luis Liberona, Jordi Molgó, Enrique Jaimovich
2002· British Journal of Pharmacology73doi:10.1038/sj.bjp.0704980

1. The action of the main ciguatoxin involved in ciguatera fish poisoning in the Pacific region (P-CTX-1b) was studied in myotubes originated from rat skeletal muscle cells kept in primary culture. 2. The effect of P-CTX-1b on sodium currents at short times of exposure (up to 1 min) showed a moderate increase in peak Na+ current. During prolonged exposures, P-CTX-1b decreased the peak Na+ current. This action was always accompanied by an increase of leakage currents, tail currents and outward Na+ currents, resulting in an intracellular Na+ accumulation. This effect is blocked by prior exposure to tetrodotoxin (TTX) and becomes evident only after washout of TTX. 3. Low to moderate concentrations of P-CTX-1b (2-5 nM) partially blocked potassium currents in a manner that was dependent on the membrane potential. 4. P-CTX-1b (2-12 nM) caused a small membrane depolarization (3-5 mV) and an increase in the frequency of spontaneous action potential discharges that reached in general low frequencies (0.1-0.5 Hz). 5. P-CTX-1b (10 nM) caused a transient increase of intracellular inositol 1,4,5-trisphosphate (IP(3)) mass levels, which was blocked by TTX. 6. In the presence of P-CTX-1b (10 nM) and in the absence of external Ca2+, the intracellular Ca2+ levels show a transient increase in the cytoplasm as well as in the nuclei. The time course of this effect may reflect the action of IP(3) over internal stores activated by P-CTX-1b-induced membrane depolarization.

Soil-transmitted helminth infections and nutritional status in Ecuador: findings from a national survey and implications for control strategies
Ana L. Moncayo, Raquel Lovato, Philip J. Cooper
2018· BMJ Open64doi:10.1136/bmjopen-2017-021319

Objective The estimation of prevalence and intensity of soil-transmitted helminth (STH) infections at a country-level is an essential prerequisite for the implementation of a rational control programme. The aim of this present study was to estimate the prevalence and distribution of STH infections and malnutrition in school-age children in rural areas of Ecuador. Design Cross-sectional study from October 2011 to May 2012. Setting Eighteen rural schools were randomly selected from the three ecological regions of Ecuador (coastal, highlands and Amazon basin). Participants 920 children aged 6–16 years. Main outcome measures Prevalence and intensity of STH infections associated with malnutrition (thinness/wasting or stunting). Results The results showed that 257 (27.9%) children were infected with at least one STH parasite. The prevalence of Trichuris trichiura , Ascaris lumbricoides and hookworm was 19.3%, 18.5% and 5.0%, respectively. Malnutrition was present in 14.2% of children and most common was stunting (12.3%). Compared with other regions, schoolchildren in the Amazon region had the highest STH prevalence (58.9%) of which a greater proportion of infections were moderate/heavy intensity (45.6%) and had the highest prevalence of malnutrition (20.4%). A positive association was observed between moderate to heavy infections with A. lumbricoides and malnutrition (adjusted OR 1.85, 95% CI 1.04 to 3.31, p=0.037). Conclusions Our estimate of the prevalence of STH infections of 27.9% at a national level in Ecuador is lower than suggested by previous studies. Our data indicate that schoolchildren living in the Amazon region have a greater risk of STH infection and stunting compared with children from other regions. The implementation of school-based preventive chemotherapy and nutritional supplement programmes within the Amazon region should be prioritised. Long-term control strategies require improvements in water, sanitation and hygiene.

Safety and Efficacy of Gatifloxacin Therapy for Children with Recurrent Acute Otitis Media (AOM) and/or AOM Treatment Failure
Michael E. Pichichero, Adriano Arguedas, Ron Dagan, L. Sher +3 more
2005· Clinical Infectious Diseases63doi:10.1086/431584

BACKGROUND: Because of concerns about arthrotoxicity, fluoroquinolones are restricted for use in children. This study describes the safety and efficacy of gatifloxacin when used for treatment of children with recurrent acute otitis media (ROM) or acute otitis media (AOM) treatment failure (AOMTF). METHODS: We performed an analysis of 867 children included in 4 clinical trials who had ROM and/or AOMTF and were treated with gatifloxacin (10 mg/kg once daily for 10 days). RESULTS: Gatifloxacin had adverse event rates that were similar overall to those of a comparator antibiotic (amoxicillin-clavulanate), except for increased diarrhea in children <2 years old receiving amoxicillin-clavulanate. There was no evidence of arthrotoxicity, hepatotoxicity, alteration of glucose homeostasis, or central nervous system toxicity acutely or during 1 year follow-up in any child. Regarding efficacy, in 2 noncomparative trials, the gatifloxacin cure rate of AOM was 89% (95% confidence interval [CI], 83%-95%) at the test of cure (TOC) visit, 3-10 days after completion of therapy. In 2 comparative trials of gatifloxacin versus amoxicillin-clavulanate, the efficacy of gatifloxacin was 88% (95% CI, 82%-94%). Gatifloxacin led to better clinical outcomes than amoxicillin-clavulanate for AOMTF (91% vs. 81%; P=.029), for AOMTF and age <2 years old (89% vs. 69%; P=.009), and for severe AOM in children <2 years old (90% vs. 75%; P=.012). Among children with AOMTF previously treated with amoxicillin-clavulanate or ceftriaxone injections, gatifloxacin cure rates were high (88% and 75%, respectively). CONCLUSIONS: Gatifloxacin appears to be safe for children, with no evidence of producing arthrotoxicity in 867 children exposed to the antibiotic when used as treatment for ROM and AOMTF.

A Randomized, Multicenter, Double Blind, Double Dummy Trial of Single Dose Azithromycin Versus High Dose Amoxicillin for Treatment of Uncomplicated Acute Otitis Media
Adriano Arguedas, Paz Emparanza, Richard H. Schwartz, Carolina Soley +3 more
2005· The Pediatric Infectious Disease Journal62doi:10.1097/01.inf.0000151024.11703.4a

BACKGROUND: High dose amoxicillin is recommended for the initial treatment of children with acute otitis media (AOM), particularly patients at risk for having drug-resistant Streptococcus pneumoniae. Single dose azithromycin (30 mg/kg) is considered an alternative agent for the treatment of AOM. OBJECTIVE: To compare the clinical efficacy and safety of single dose azithromycin with that of high dose amoxicillin among children with uncomplicated AOM. METHODS: This was a double blind, double dummy, multinational, clinical trial in which children (6-30 months of age) with AOM were randomized to treatment with single dose azithromycin (30 mg/kg) or high dose amoxicillin (90 mg/kg/d, in 2 divided doses) for 10 days. Tympanocentesis was performed at baseline and clinical responses were assessed at days 12-14 (end of therapy) and at days 25-28 (end of study). RESULTS: The study enrolled 313 patients, and 83% of the patients were < or =2 years of age. A total of 158 patients in the azithromycin group and 154 in the amoxicillin group were considered clinical modified intent-to-treat patients. A middle ear pathogen was detected for 212 patients (68%). Haemophilus influenzae was the most common pathogen (isolated for 96 patients), followed by S. pneumoniae (92 patients), Moraxella catarrhalis (23 patients) and Streptococcus pyogenes (23 patients). beta-Lactamase production was observed for 17% of H. influenzae isolates and 100% of M. catarrhalis isolates. Thirty-five (38%) S. pneumoniae isolates were penicillin-nonsusceptible and 24 (26%) isolates were macrolide-resistant. At the end of therapy, clinical success rates for azithromycin and amoxicillin were comparable for all patients (84 and 84%, respectively) and for children < or =2 years of age (82 and 82%, respectively). At the end of therapy and end of study, clinical efficacies among all microbiologic modified intent-to-treat evaluable subjects were comparable for patients treated with azithromycin (80%) and patients treated with amoxicillin (83%). The rates of treatment-related adverse events for azithromycin and amoxicillin were 20% and 29%, respectively (P = 0.064). Diarrhea was more common in the amoxicillin group than in the azithromycin group (17.5 and 8.2%, respectively) (P = 0.017). Compliance, defined as completion of > or =80% of the study medication, was higher in the azithromycin group (100%) than in the amoxicillin group (90%) (P = 0.001). CONCLUSIONS: In this study, single dose azithromycin was as effective as high dose amoxicillin for the treatment of children with AOM, whereas rates of adverse events were lower and compliance improved with the simplified single dose regimen.

Stroke and Pneumonia: Mechanisms, Risk Factors, Management, and Prevention
Idan Grossmann, Kevin Rodriguez, Mridul Soni, Pranay K Joshi +4 more
2021· Cureus60doi:10.7759/cureus.19912

A stroke is a cerebrovascular medical emergency characterized by the sudden loss of neurological function due to interruption to the blood supply. A serious and common complication of stroke is pneumonia. This review article outlined various studies in order to understand the pathogenesis pathways that lead to the development of stroke-associated pneumonia, as well as therapeutic and preventive options to reduce pneumonia. The article looked for risk factors that increase the risk of developing pneumonia among stroke patients. In addition, it has reviewed various therapeutic modalities, such as postural modifications, pharmacological treatment, and other unique treatments, in an attempt to find which of them are efficient to decrease the occurrence of pneumonia and which of them are not. The article also attempts to emphasize the importance of early screening for dysphagia among stroke patients and demonstrates the importance of preventive strategies that can be easily implemented, such as routine oral care and behavioral modifications.