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Este escrito se basa en una investigación conjunta entre académicas de la Universidad Nacional de Costa Rica y académicas de las universidades de California EE. UU: Redlands, California State University San Marcos y National University que se lleva a cabo en los años 2020 y 2021, la cual pretende conocer las prácticas docentes a nivel de preescolar relacionadas con el desarrollo de habilidades prelectoras en ambos contextos. Como resultado de las entrevistas aplicadas a treinta personas docentes, quince de cada país, se identifican puntos de encuentro y particularidades de las prácticas docentes, además se determinan estrategias evaluativas utilizadas para valorar las habilidades prelectoras en la niñez preescolar, así como los desafíos que enfrentan las personas docentes de cada país, por último, establecer el interés de propiciar oportunidades de colaboración y aprendizaje entre colegas de ambas nacionalidades. Se concluye que, las prácticas docentes, con la intención de desarrollar habilidades prelectoras, coinciden en el resguardo y consideración de las características del grupo etario; además, sus prácticas incluyen el uso de material impreso, el juego y el arte entre otros, como vehículos para integrar al niño y la niña al mundo letrado en el salón de clases. Asimismo, se toma en cuenta la necesidad y reto de considerar el contexto al diseñar estrategias desde lo cotidiano y significativo, promoviendo en el aula situaciones reales de la niñez como conversaciones y dramatizaciones para el desarrollo de lenguaje oral y el vocabulario.

To identify patient factors in older patients associated with making posttreatment visits in the first year after major head and neck oncologic surgery.Retrospective cohort study.Academic institution.Patients aged ≥60 years who underwent a neck dissection with or without a free flap reconstruction were retrospectively analyzed. Data collected included patient demographics, comorbidities, social variables, perioperative course, and clinical visits.Within a 1-year postoperative period, the 181 patients in our cohort had a mean ± SD 6.37 ± 3.6 postoperative clinic visits; 70% attended at least 4 visits. Multivariable regression analysis showed a significant association with distance closer to the hospital (Older patients who undergo major head and neck oncology surgery are more likely to attend posttreatment visits in the 1 year following surgery if they are discharged home rather than to a skilled nursing facility, live closer to the hospital, and undergo adjuvant radiation therapy.

OBJECTIVE: To investigate a possible link between breast and thyroid cancer. METHODS: A multi-center retrospective review of patients in the electronic medical records of six Accrual to Clinical Trial (ACT) institutions with both breast cancer and thyroid carcinoma. Each center queried their data using a predefined data dictionary. Information on thyroid and breast cancer included dates of diagnosis, histology, and patient demographics. RESULTS: A random effects model was used. There were 4.24 million women’s records screened, 44,605 with breast cancer and 11,846 with thyroid cancer. The relative risks observed at each institution ranged from 0.49 to 13.47. The combined risk ratio estimate was 1.77 (95% CI: 0.50 – 5.18). CONCLUSION: There was no association between risk of developing thyroid cancer and being a breast cancer survivor compared to no history of breast cancer, but the range of relative risks among the participating institutions was wide. Our findings warrant further study of more institutions with a larger sample size. Additionally, further analysis of the significance of regional risk ratio differences may be enlightening. LEVEL OF EVIDENCE: 3

Objectives: To elucidate the frequency and types of pre- and post-interview communication that applicants engage with programs, to garner the perceptions of both applicants and program directors (PDs), and determine if communication influences outcomes. Subjects and Methods: Electronic surveys were distributed to otolaryngology residency applicants, and to PDs of ACGME-accredited otolaryngology programs after the 2018 to 2019 application cycle. Results: 93 of 324 applicants (28.7%) and 33 of 106 PDs (31.3%) responded. In the pre-interview period, 58.1% of applicants sent emails of interest, and 41.9% had a mentor initiate communication. In the post-interview period, the majority of applicants (82.8%) sent notes of intent to their number one choice, and 32.3% had a faculty mentor communicate this on their behalf. The majority of PDs (84.8%) were undecided or did not believe that emails of interest influence decisions to offer an interview, whereas 81.8% believed that communication initiated by an applicant’s mentor has an impact on interview offers. No PD agreed that declarations of intent from applicants have an impact on their rank lists, while only 33.3% of PDs believed that a mentor communicating this for an applicant has some impact. Our statistical findings are in agreement with these perceptions as neither applicant-initiated pre-interview ( P = .54), mentor-initiated pre-interview ( P = .62), applicant-initiated post-interview ( P = .11) nor mentor-initiated post-interview ( P = .78) communications influenced the number of interviews received or ultimate match outcome. Conclusion: Pre- and post-interview communication practices vary widely among otolaryngology applicants. Applicant-initiated communication has no impact on outcomes, while mentor-initiated communication is perceived to have more benefit, despite not impacting interview or match outcomes in this study.

The purpose of this study is to characterize deficits in olfactory-specific and sinonasal-specific QoL after total laryngectomy (TL) with validated patient reported outcome measures.Thirty patients who had a TL were prospectively enrolled. Patient demographics, as well as scores from the Questionnaire of Olfactory Disorders Negative Statements (QOD-NS) and the Sino-nasal Outcome Test-22 (SNOT-22) were collected. Univariate analysis was performed to assess associations between patient characteristics and QoL scores.The average QOD-NS score was 37.9 ± 11.4 (38.5 is considered abnormal) and average SNOT-22 score was 32.0 ± 3.8 (20 indicates a moderate/severe impact on QoL). The abnormal QOD-NS group had a greater percentage of former smokers compared to the normal group (77.8% vs. 58.1%; P = 0.56) and more median days from surgery compared to the normal group (904 vs. 477 days; P = 0.24).Olfactory dysfunction associated with TL results in blunting of olfactory-specific QoL.

Opinion statementAs the field of oncology enters the era of precision medicine and targeted therapies, we have come to realize that there may be no single "magic bullet" for patients with head and neck cancer. While immune check point inhibitors and some targeted therapeutics have shown great promise in improving oncologic outcomes, the current standard of care in most patients with head and neck squamous cell carcinoma (HNSCC) remains a combination of surgery, radiation, and/or cytotoxic chemotherapy. Nevertheless, advances in precision medicine, next-generation sequencing (NGS), and targeted therapies have a potential future in the treatment of HNSCC. These roles include increased patient treatment stratification based on predictive biomarkers or targetable mutations and novel combinatorial regimens with existing HNSCC treatments. There remain challenges to precision medicine and NGS in HNSCC, including intertumor and intratumor heterogeneity, challenging targets, and need for further trials validating the utility of NGS and precision medicine. Additionally, there is a need for evidence-based practice guidelines to assist clinicians on how to appropriately incorporate NGS in care for HNSCC. In this review, we describe the current state of precision medicine and NGS in HNSCC and opportunities for future advances in this challenging but important field.

ObjectivesHead and neck cancer surgeons frequently interact with dying patients with advanced disease and their families, but little is known about their bereavement practices after a patient's death. The aim of this study is to elucidate the frequency of common bereavement practices, cited barriers to bereavement, and predictive physician factors that lead to an increase in bereavement practices among head and neck cancer surgeons.MethodsA 20-item survey was sent to 827 active surgeons of the American Head and Neck Society. Approval was obtained and the survey was distributed through the American Head and Neck Society. Demographics, frequency of common bereavement practices, empathy, and barriers were assessed. Multiple linear regression was performed to determine physician factors associated with more frequent bereavement follow-up.ResultsThere were 156 respondents (18.9% response rate). Overall, surgeons were more likely to usually/always call (48.5%) or send a letter (42.4%) compared with other practices such as attending funerals (0%), offering family meetings (18.6%), or referring family members to counseling (7.7%). Many barriers were cited as being at least somewhat important: being unaware about a patient's death (67.3%) was the most cited, whereas 51.3% cited a lack of mentorship/training in this area. Scoring higher on empathy questions (P≤ .001) was associated with more frequent surgeon bereavement follow-up with the family of deceased patients.ConclusionThere is substantial practice variation among surgeons suggesting a lack of consensus on their roles in bereavement follow-up. Having higher empathy was predictive of higher engagement.Level of evidenceNA Laryngoscope, 132:1971-1975, 2022.

Objective To determine the accuracy of the Pediatric Sleep Questionnaire (PSQ) as a screening tool for obstructive sleep apnea in children with craniofacial anomalies. Design Retrospective cohort study. Setting Multidisciplinary cleft and craniofacial clinic at a tertiary care center. Patients Children with craniofacial anomalies 2 to ≤18 years of age who both completed a PSQ screen and underwent polysomnography (PSG) without interval surgery. Main outcome measures Sensitivity and specificity of the PSQ in detecting an obstructive apnea-hypopnea index (AHI) ≥ 5 events/hour. Results Fifty children met study criteria, with 66% (n = 33) having an associated syndrome. Mean patient age at time of PSQ was 9.6 + 4.0 years. Overall, 33 (64%) screened positive on the PSQ, while 20 (40%) had an AHI ≥ 5. The sensitivity and specificity for identifying AHI ≥ 5 was 70% and 40%, respectively. With subgroup analysis, the sensitivity and specificity were higher (100% and 50%) in children with non-syndromic palatal clefting but lower (65% and 31%) in children with a syndrome or chromosomal anomaly. There was no correlation detected between PSQ score and AHI severity (p = 0.25). The mean obstructive AHI in the study population was 10.1 ± 22.7 despite 44% (n = 22) undergoing prior adenotonsillectomy. Conclusions The PSQ was less sensitive and specific in detecting an AHI ≥ 5 in children with craniofacial anomalies than in a general population, and particularly poor in for children with syndrome-associated craniofacial conditions. Given the high prevalence of OSA in this patient population, a craniofacial-specific validated screening tool would be beneficial.

Objectives To describe the impact that the coronavirus disease 2019 (COVID-19) pandemic had on the presentation of patients with head and neck cancer in a single tertiary care center. Study Design Retrospective cohort study. Setting Academic institution. Methods We performed a retrospective review of patients with newly diagnosed head and neck squamous cell carcinoma (HNSCC) who presented as new patients between September 10, 2019, and September 11, 2020. Patients presenting during the 6 months leading up to the announcement of the pandemic (pre–COVID-19 period) on March 11, 2020, were compared to those presenting during the first 6 months of the pandemic (COVID-19 period). Demographics, time to diagnosis and treatment, and tumor characteristics were analyzed. Results There were a total of 137 patients analyzed with newly diagnosed malignancies. There were 22% fewer patients evaluated during the COVID-19 timeframe. The groups were similar in demographics, duration of symptoms, time to diagnosis, time to surgery, extent of surgery, and adjuvant therapy. There was a larger proportion of tumors classified as T3/T4 (61.7%) in the COVID-19 period vs the pre–COVID-19 period (40.3%) ( P = .024), as well as a larger median tumor size during the COVID-19 period ( P = .0002). There were no differences between nodal disease burden ( P = .48) and distant metastases ( P = .42). Conclusion Despite similar characteristics, time to diagnosis, and surgery, our findings suggest that there was an increase in primary tumor burden in patients with HNSCC during the early COVID-19 pandemic.

Otolaryngology is a small and highly sought-after surgical subspecialty with sparse residency positions, making it competitive to match into. Allopathic (MD) students without home otolaryngology residency programs, osteopathic (DO) medical students, and underrepresented minorities have historically faced additional challenges in matching into otolaryngology. These specific populations generally experience limited opportunities in establishing mentors, engaging in scholarly activity, and gaining early exposure to clinical settings. Even though the American Osteopathic Association and the Accreditation Council for Graduate Medical Education merger was in part established to create equity among applicants, there remains a substantial disparity among the match rates of medical students of various educational and cultural backgrounds. The National Otolaryngology Interest Group is a student-led interest group created to provide all medical students, especially those facing barriers, with the resources needed to best prepare for matching into an otolaryngology residency program and ultimately a career in otolaryngology.

Objective Applicant demographics during the 2019-2020 residency cycle were evaluated to determine if strict utilization of United States Medical Licensing Examination (USMLE) scores in applicant selection could lead to a restriction in diversity. Study Design Cross-sectional study. Setting Otolaryngology residency applicants to a single institution. Methods A total of 381 applicants were analyzed by age, gender, applicant type, race/ethnicity, USMLE scores, permanent zip code, and graduating medical school. Results Among applicants, 37% were women; 9% were ≥30 years of age; 12% were underrepresented minorities (URMs); 71% to 81% had above-average socioeconomic surrogate markers; 22% were from a top 25 US News & World Report –ranked institution; and 81% were from an institution with an otolaryngology residency program. There was no increase in applicants who identified as URM from the 2015-2020 cycles. Multivariable regression analysis showed that applicants who were international medical graduates, URMs, and ≥30 years of age had lower Step 1 and Step 2 scores ( P < .05). Applicants who identified as women had a lower Step 1 score, and those from top 25 National Institutes of Health–funded institutions had a higher Step 1 score; however, there was no difference when Step 2 scores were compared ( P > .05). Conclusion Our data suggest that in the pre–USMLE Step 1 pass/fail setting, strict adherence to USMLE scores may lead to disproportionally low recruitment of applicants who are women, ≥30 years of age, URMs, and from institutions without an otolaryngology residency program. We must implement measures against overemphasizing the absolute values of USMLE scores for a true holistic review of applicants, specifically to prevent an overemphasis on the USMLE Step 2 score.

Overhead transmission lines are probably the electrical component most vulnerable to lightning, short circuits, human errors, overloads and ageing due to the long trajectories they have. In this paper, the operation of the Distance Relay (21-ANSI/IEEE Standard Device Number) as primary or main protection as well as backup protection for overhead transmission lines is analyzed. The relay was modeled by using the ATP/EMTP program in order to visualize its response to different fault conditions and apparent impedance trajectories in the R-X complex diagram. MODELS programming language is used, which allows to implement algorithms that are used for structuring the functions and the operation logics of the relay. The relay behaviour under fault conditions at different locations along the line is validated by comparing it with the fault records from a real event in the electric power system of mexican utility.

Purpose of review This article reviews recent literature on repair of peripheral nerve injuries in the head and neck with a focus on autografts, allografts, nerve conduits, and technical considerations. Recent findings Contemporary nerve grafting techniques offer the potential to improve peripheral nerve outcomes and reduce donor site morbidity. A variety of donor nerves autografts have been described that offer favorable outcomes for segmental reconstruction of facial nerve defects. Recent studies have demonstrated promising results in repair of inferior alveolar nerve injuries with human allografts. Animal models describe successful reinnervation of small defects with neural conduits. The latest data do not favor protocolled nerve graft polarity or use of a motor versus sensory donor nerves. Summary Interposition nerve grafting is the gold standard for repair of peripheral nerve injuries when a tension-free primary neurorrhaphy is not possible. Autografts are the work-horse for the majority of head and neck neural defects, however, can result in some degree of donor site morbidity. Recent developments in allografting and neural conduits have the potential to further diversify the head and neck reconstructive surgeon's armamentarium. It is unclear if nerve graft makeup or polarity affect functional outcome.

Rhinoplasty for cleft lip nasal deformities challenges all cleft surgeons. There is great variability of phenotypical anatomy, but iatrogenic changes and scarring from the previous surgeries add another layer of complexity. Rhinoplasties on a patient with cleft lip–palate are technically and intellectually challenging to master requiring a patient-tailored approach. The shape and structure of the nose are changed to improve both function and aesthetic appearance. In the primary setting, nasoalveolar molding is a form of presurgical infant orthopaedics used for preparation before the cleft lip and nose repair. Intermediate stages should be conservative to minimize scarring, while the definitive cleft rhinoplasty utilizes cartilage grafts from septum, ear, or rib to sculpt the nose. Hereinto, we will outline the controversies, the evidence supporting certain techniques, and our preferences.

Sugarcane production can be affected by extreme environmental conditions, such as drought stress. This study focused on establishing a screening method to evaluate and select drought tolerant germplasm of Saccharum species. A new drought screening methodology is presented in this paper. A randomized block design experiment was conducted under greenhouse conditions with 2 months old seedlings of five genotypes of Saccharum spontaneum (IRAN 28, JW43, TUS12-72, TUS12-23, X08-0299) and one genotype of a commercial cultivar (Saccharum spp. CP72-1210), under well-irrigated and water stress conditions. Three treatments were established with irrigation intervals at 3, 6, and 9 days, with four replicates per each genotype in each treatment. Evapotranspiration, stomatal conductance, total biomass, leaf death rate, rate of new tillers and shoot growth were evaluated during the experiment. JW43 and CP72-1210 presented the highest values of stomatal conductance with non-significant differences. Accumulated water used by all the genotypes was significantly different among the three treatments. Also, significant differences were found in the total dry biomass among all the treatments. Results showed that TUS12-23 genotype can be classified as very tolerant to drought stress and JW43 is the less tolerant, whereas the other genotypes could be susceptible and may survive under mild drought conditions. Results also indicated that the methodology used, and the parameters measured are effective in identifying sugarcane germplasm with extreme reaction to drought stress. Key words: Drought stress, Saccharum species, biomass, stomatal conductance, agronomic parameters.

To provide a comprehensive, up-to-date guide for the surgical management of the most common malignant and benign thyroid diseases within the pediatric population. 26.4% of nodules are malignant in the pediatric population. Concerning ultrasound features of hypoechogenicity, irregular margins, increased intranodular blood flow, or microcalcifications should prompt FNA, while size criteria is less important. The Bethesda System is effective in stratifying risk in pediatric nodules. The role of molecular genetic testing to guide patient management is emerging. Total thyroidectomy has become more frequent in the treatment of differentiated thyroid cancer due to its aggressive nature in the pediatric population and concern for recurrence. The role of adjunctive radiofrequency iodine ablation and the impact of extensive resection on survival are controversial. Management of pediatric thyroid disease can be complex and should be managed by a multidisciplinary team with an experienced, high-volume surgeon.

The escalation of the COVID-19 pandemic has affected health care at every level, including medical education. As some fourth-year medical students graduate early to join the front lines, we must now turn our attention to those trainees in their penultimate year. In this commentary, we address the unique dilemmas facing otolaryngology residency candidates for the 2020-2021 cycle, with a focus on those applicants with no institutional otolaryngology department.

OBJECTIVE Dental implant placement in scapular free flaps is challenging. This study examines the scapula with computed tomography to identify ideal locations for predictable implant placement during preoperative planning. METHODS Sixty-eight adult patient chest CT scans (34 men, 34 women) captured for various medical indications, were analyzed for age, height, weight, and scapula length. The lateral border of the scapula was divided into six equal segments; the midpoints of each segment (labeled proximally to distally as 1M-6M) were analyzed in cross-section as potential recipient sites for 3.5 × 8 mm implants. Also, we present a case of a 77-year-old male with ameloblastoma of the mandible who underwent patient specific planning and received a scapular free flap with dental implant placement. RESULTS There was greater bone availability in males with a mean depth of 8.3 ± 2.8 versus 5.1 ± 3.3 mm in females (p

A new lignan, 3,4,5'-trimethoxy-3',4'-methylenedioxy-7,9':7',9 diepoxylignan (1) (6-[4-(3,4-dimethoxy-phenyl)-tetrahydro-furo[3,4-c.]furan-1-yl]-4-methoxy-benzo[ ] dioxole) together with two known lignans, 7'-epi.-sesartemin (2) and diayangambin (3), and a known flavonoid, 5-hydroxy-7,4'-dimethoxyflavone (4), were isolated from the leaves of Piper fimbriulatum. C. DC. Their structures were assigned by a combination of one- and two-dimensional NMR techniques. 7'-epi.-Sesartemin (2) showed the highest larvicidal activity against Aedes aegypti. (LC100 17.6 µg/ml) and weak antiplasmodial (IC50 7.0 µg/ml) and antitrypanosomal (IC50 39.0 µg/ml) activities. None of the compounds was active against Leishmania mexicana..

International audience; Electric models of battery have to take into account the effect of temperature for the state-of-charge estimation. As a matter of fact, at low temperature the driving range of the vehicle can be overestimated up to more than 20% with electric only models. We propose to couple thermal and electric battery models for improving the range estimation.

Proteases are considered integral to most if not all physiological processes and their dysregulation is involved in many diseases. Proteases are hydrolytic enzymes that process proteins by cleavage of amide bonds. Proteases enzymatically process proteins to modify their activity and compartmentalization. Proteolytic processing fulfills diverse regulatory roles: for example proteolysis can generate mature protein forms, allow the accessibility of active sites to substrates, remove signal sequences, and transmembrane domains that embed receptors and membrane proteins in the plasma membrane, and modulate signaling cascades upon ligand-binding. Proteolytic processing generates novel N-termini (neo-N-termini) in proteins, i.e., biological starts to proteins that cannot be predicted from genome information alone. It is the identification and quantification of neo-N-termini in a high throughput and confident fashion that presents one of the greatest challenges in proteomic technologies in the field that has come to be known as degradomics. For a protease of unknown function, identification of substrates and cleavage site specificity provides critical information for the putative biological role of the protease. Here we describe the most successful and widely adopted current mass spectrometry-based methodologies to study the degradome – the complement of all proteases and their substrates. A brief discussion of the principles of each of the approaches used to identify protease substrates, and a short description of cleavage site identification strategies are presented. These approaches are discussed in the context of the network of protease interactions, termed the protease web, emphasizing the importance of validation by in vitro and in vivo models to generate biological knowledge.

In order to explore rationally the medical potential of the plant biodiversity of the Central and South American region as a source of novel antiparasitic molecules, a multinational Organization of American States (OAS) project, which included the participation of multidisciplinary research centers from Argentina, Bolivia, Colombia, Costa Rica, Guatemala, Nicaragua and Panama, was carried out during the period 2001-2004. This project aimed at screening organic plant extracts for antitrypanosomal, antileishmanial and antimalarial activities and subsequently isolating and characterizing bioactive molecules. Plants for antiparasitic screening were selected from a database of ethnomedical uses of Latin American plants (PlanMedia) based on the amount of biological and chemical information available in the literature. We report here the evaluation of 452 extracts from 311 plant species in vitro screens against Plasmodium falciparum, Leishmania mexicana, and Trypanosoma cruzi. Out of 311 species tested, 17 plants (5.4%) showed antiparasitic activities at IC50 values ≤ 10 µg/mL. The most active plants were Acnistus arborescens (L.) Schltdl. (Solanaceae) (leaf, EtOH, IC50: 4 µg/mL) Monochaetum myrtoideum Naudin (Melastomataceae) (leaf, MeOH, IC50: 5 µg/mL) and Bourreria huanita (Lex.) Hemsl. (Boraginaceae) (branch, EtOH, IC50: 6 µg/mL). These were selectively active against P. falciparum, L. mexicana and T. cruzi, respectively. UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Química

Syphilis may present with a myriad of oral manifestations in the primary, secondary, and tertiary stages, and may be confused with malignancy. Despite a rise in the incidence of syphilis, tertiary syphilis is exceedingly rare. Tertiary syphilis gummas usually affect the hard palate, while tongue involvement is very rare. A 55-year-old male with extensive smoking and alcohol use was referred for malignancy evaluation with an ulcerative mass creating a tongue cleft, and a positron emission tomography scan suggestive for malignancy. Biopsy results demonstrated no carcinoma but histology demonstrated granulomatous inflammation. Further laboratory results demonstrated elevated rapid plasma reagin titers with Treponema pallidum immunoglobulin G antibodies present. The patient was diagnosed with tertiary syphilis, received appropriate antibiotic therapy, and had healing of the tongue with a persistent cleft. Syphilis may mimic many disease processes. As such, it is important to include this disease in the differential of an unusual tongue lesion. An oral lesion may be the first sign of infection.

This study was designed to determine the effect of Mangifera indica flowers decoction, on the acute and subacute models of induced ulcer in mice and rats. A single oral administration of the aqueous decoction (AD) from M. indica up to a dose of 5 g/kg, p.o. did not produce any signs or symptom of toxicity in the treated animals. The oral pre-treatment with AD (250, 500 and 1000 mg/kg) in rats with gastric lesions induced by ethanol, decreased the gastric lesions from 89.0 ± 6.71 (control group) to 9.25 ± 2.75, 4.50 ± 3.30 and 0, respectively. Pretreatment with AD (250, 500 and 1000 mg/kg) to mice with HCl/ethanol- or stress-induced gastric lesions resulted in a dose-dependent significant decrease of lesion index. In the piroxicam-induced gastric lesions, the gastroprotective effect of AD was reducing with the increase of the AD dose. In the pylorus-ligature, AD (p.o.) significantly decreased the acid output indicating the antisecretory property involved in the gastroprotective effect of M. indica . Treatment with AD during 14 consecutive days significantly accelerated the healing process in subacute gastric ulcer induced by acetic acid in rats. Pretreatment with N -nitro- l -arginine methyl ester ( l -NAME), an inhibitor of NO-synthase, did not abolish the gastroprotective effects (99% with saline versus 80% with l -NAME) of AD against ethanol-induced gastric lesions. Pretreatment with N -ethylmaleimide (NEM), a blocker of endogenous sulphydryl group, significantly abolished the protective effects of AD against ethanol-induced gastric ulcers (95% with saline versus 47% with NEM). Phytochemical screening showed the presence of steroids, triterpenes, phenolic compounds and flavonoids. Estimation of the global polyphenol content in the AD was performed by Folin–Ciocalteu method and showed approximately 53% of total phenolic on this extract. These findings indicate the potential gastroprotective and ulcer-healing properties of aqueous decoction of M. indica flowers and further support its popular use in gastrointestinal disorders in Caribbean.

Three new lactone derivatives, (3E.)-5,6-dihydroxy-3-(3-hydroxy-4-nonyl-5-oxofuran-2(5H.)-ylidene)-7-nonyl-1-benzofuran-2(3H.)-one (1), (3E.)-5,6-dihydroxy-3-(3-hydroxy-4-decyl-5-oxofuran-2(5H.)-ylidene)-7-decyl-1-benzofuran-2(3H.)-one (2), and (3E.)-5,6-dihydroxy-3-(3-hydroxy-4-undecyl-5-oxofuran-2(5H.)-ylidene)-7-undecyl-1-benzofuran-2(3H.)-one (3), denominated as parathesilactones A, B, C, respectively, and two new quinone derivatives, (2,7,8-trihydroxy-3,6-didecyldibenzo[b,d.]furan-1,4-dione (4) and (2,7,8-trihydroxy-3,6-dinonyldibenzo[b,d.]furan-1,4-dione) (5), denominated as parathesiquinones A, B, respectively, were isolated from the branches of Parathesis amplifolia. Lund. (Myrsinaceae). In addition, three known triterpenes, α.-amyrin (6), β.-amyrin (7), and bauerenol (8), and four known alkenylresorcinols, 5-pentadec-8-enyl resorcinol (9), 5-pentadec-10-enyl resorcinol (10), 5-heptadec-8-enyl resorcinol (11), and 5-heptadec-10-enyl resorcinol (12), were also isolated. The structure elucid...

The SRB cytotoxicity assay was used to screen plant extracts, in a collaborative multinational OAS project involving Argentina, Bolivia, Colombia, Costa Rica, Guatemala, Nicaragua and Panama, against breast (MCF-7), lung (H-460), and central nervous system (SF-268) human cancer cell lines. Out of 310 species tested, 23 (7.4%) plants showed cytotoxic activity at GI50 values ≤10 µg/ml. The most active plants were Thevetia ahouai., Physalis viscosa., Piper jacquemontianum., Piper barbatum., Senna occidentalis., Tovomita longifolia., and Lippia cardiostegia.. Blepharocalyx salicifolius. and Senna occidentalis. were selectively active against one cell line, SF-268 or MCF-7, respectively. Within the framework of this project, 14 compounds have been isolated, 5 new (4 benzophenones, coumarin) and 9 known to the literature. But only the bioassay-guided fractionation of the active extract of Piper barbatum. leaves, which led to the isolation of three known compounds: (2′E., 6′E.)-2-farnesyl-1,4-benzoquinon...

El complejo calahuala son especies de la familia Polypodiaceae. (Phlebodium pseudoaureum y P.decumanum') utilizadas comúnmente para el tratamiento de afecciones gastrointestinales, respiratorias, cardíacas, renales, reumatismo, diabetes, hipertensión, tópicamente se usa en psoriasis, eczema, úlceras y como protector solar. Se ha demostrado por pruebas farmacológicas actividad antiinflamatoria, Inmunomoduladora. fotoprotcctiva, y estimuladora de la actividad cerebral. En el presente trabajo se comparó el perfil eromatográfico de extractos de frondas y rizomas de P. decumanum y P. pseudoaureum mediante cromatografía en capa fina (TLC) y cromatografía líquida de alia resolución (HPLC) con el objetivo de determinar diferencias fitoquímicas entre las especies y proponer algunas moléculas que pudieran usarse para estandarizar sus extractos. De acuerdo a los resultados obtenidos en HPLC se determinó que los extractos de frondas y rizomas de P decumanum y P. pseudoauruem presentan diferencias fitoquímicas significativas, demostrándose mayor cantidad de metabolites en las frondas, en las cuales se identificó ácido clorogcnico en P.decumanum y ácido caféico en P. pseudoauruem. Por TLC se evidencian como metabolitescaracterísticos, la presencia de flavonoides en las frondas y la de saponinas en los rizomas.

Citrus tristeza virus (CTV) isolates collected from the Lower Rio Grande Valley in south Texas and east Texas were characterized using citrus indicators and molecular methods. The citrus indicators were Mexican lime (Citrus aurantifolia), sour orange (C. aurantium), sweet orange (C. sinensis) grafted to sour orange, Duncan grapefruit (C. × paradisi), and Madam Vinous sweet orange, with some CTV isolates additionally indexed using the Texas commercial grapefruit cvs. Rio Red and Star Ruby, and Marrs and N-33 sweet orange. Severity ratings used 11 biotype groups or cumulative mean relative indices. Molecular characterization was carried out using poly- and monoclonal antibodies, seven strain-specific probes and single-stranded conformational polymorphism, and all were based on the CTV major coat protein or gene. All Texas CTV isolates produced vein clearing symptoms on inoculated Mexican lime plants. Over half of the CTV isolates tested were placed in biotype groups IX and X (causing decline of sweet orange on sour orange, seedling yellows on sour orange and grapefruit seedlings, and stem pitting of grapefruit or sweet orange), and one isolate was in biotype I (mild).

Bioassay-guided fractionation of the CH(2)Cl(2) extract of the leaves of Marila pluricostata led to the isolation of 17 naturally occurring 4-phenylcoumarins, three of them, 5-hydroxy-8,8-dimethyl-4-phenyl-9,10-dihydro-8H-pyrano-[2,3-f]chromen-2-one (1), 5-hydroxy-8,8-dimethyl-4-phenyl-6-propionyl-9,10-dihydro-8H-pyrano-[2,3-f]chromen-2-one (2), and 5,7-dihydroxy-8-(3-methylbut-2-enyl)-4-phenylchromen-2-one (3), are new natural compounds; the remaining (4-17) are known mammea-type coumarins. Their structures were established by spectroscopic means. All compounds were tested in cytotoxicity assays against the MCF-7, H-460, and SF-268 human cancer cell lines.

Fifty-one extracts, from six Panamanian plants species selected on the basis of their toxicities against Artemia salina, belonging to five families and five genera, were screened for their in vitro anticancer (TK-10, UACC-62, MCF-7) and immunomodulatory activities [inhibition of complement, classical (CP) and alternative (AP) complement pathway and lymphoproliferation]. The results showed that 9 (17.6%) of 51 extracts presented anticancer activity against cancer cell lines, while 28 (54.9%) of 51 extracts stimulated normal spleen cells proliferation, and 25 (49.0%) inhibited in vitro lymphoid tumor cell growth. Finally, 7 (19.4%) and 10 (27.8%) out of 36 extracts showed high and moderate anticomplementary activity on CP, respectively. Moreover, out of 36 extracts, 1 (2.8%) produced higher inhibition while 4 (11.1%) showed moderate inhibition in the alternate pathway. The dichloromethane, methanolic and aqueous extracts from the leaf (3.0, 3.2, 4.2) and branch (3.5, 5.7, 5.8) of Trichospermum galeottii and from the leaf (2.4, 2.5, 5.6) and stem (2.3, 2.3, 4.7) of Sauraria yasicae were the most active immunomodulatory plants. The dichloromethane extract from the root of Morinda panamensis (8.7, 4.4, 6.3) was active against the three cancer cell lines, while the dichloromethane extract from the bark of Trichospermum galeottii (TK-10 ¼ 3.4,UACC-62 ¼ 9.4) and the bark of Morinda panamensis (UACC-62 ¼ 5.5, MCF-7 ¼ 5.9) as well as the methanolic extract from the root of Morinda rojoc (UACC-62 ¼ 9.2, MCF-7 ¼ 9.4) exhibited selectivity against two cancer cell lines.

Ten novel neo -clerodane diterpenoids, named cornutins C–L, have been isolated from the leaves of Cornutia grandifolia var . intermedia . Their structures have been elucidated by detailed spectroscopic analysis. In addition, the in vitro antiplasmodial activity of four isolated compounds (cornutin C–F) has been evaluated, revealing only a marginal activity.

Tropical forests are one of the most diverse and endangered habitats on earth. They have also been portrayed as a source of future pharmaceuticals, yet finding useful compounds can be both scientifically and politically challenging. Increasingly, over the past decade, the potential value of medicinal compounds derived from plants, microorganisms, and animals has been proposed as a tangible benefit of biodiversity, and therefore a basis for promoting its preservation. Ecological theories of plant defense can increase the probability of discovering compounds with activity in bioassays against human disease targets. In addition, conducting research in tropical countries with local scientists provides immediate and lasting benefits for the sustainable use of biodiversity. This new approach to drug discovery has been effective in identifying bioactive leads. It is both an important step towards understanding the medicinal value of biodiversity, and a practical way to link drug discovery with conservation.