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1.
Autops Case Rep ; 14: e2024495, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39021465
3.
7.
Sci Rep ; 12(1): 19848, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36400941

RESUMEN

Stickiness of vegetative tissues has evolved multiple times in different plant families but is rare and understudied in flowers. While stickiness in general is thought to function primarily as a defense against herbivores, it may compromise mutualistic interactions (such as those with pollinators) in reproductive tissues. Here, we test the hypothesis that stickiness on flower petals of the High-Andean plant, Bejaria resinosa (Ericaceae), functions as a defense against florivores. We address ecological consequences and discuss potential trade-offs associated with a repellant trait expressed in flowers that mediate mutualistic interactions. In surveys and manipulative experiments, we assess florivory and resulting fitness effects on plants with sticky and non-sticky flowers in different native populations of B. resinosa in Colombia. In addition, we analyze the volatile and non-volatile components in sticky and non-sticky flower morphs to understand the chemical information context within which stickiness is expressed. We demonstrate that fruit set is strongly affected by floral stickiness but also varies with population. While identifying floral stickiness as a major defensive function, our data also suggest that the context-dependency of chemical defense functionality likely arises from differential availability of primary pollinators and potential trade-offs between chemical defense with different modes of action.


Asunto(s)
Flores , Herbivoria , Simbiosis , Plantas , Colombia
8.
Autops Case Rep ; 11: e2021276, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34249787

RESUMEN

Adamantinoma of the long bones is an exceedingly rare and slow-growing tumor that affects the diaphysis of long bones, particularly the tibia. Based on the pattern of the epithelial cell component and the presence or absence of the osteofibrous dysplasia-like element, several histological variants have been described, such as (i) tubular (the most frequent), (ii) basaloid, (iii) squamous, (iv) spindle variant, (v) osteofibrous dysplasia -like variant, and (vi) Ewing's sarcoma - like adamantinoma (the least frequent). The diagnosis may be challenging since this tumor may be mistakenly interpreted as carcinoma, myoepithelial tumor, osteofibrous dysplasia, and vascular tumor. We report the case of a 41-year-old male who presented with swelling over the right leg associated with pain. The X-ray showed a lytic lesion of the right-sided tibia. The diagnosis of adamantinoma was made based on the clinico-radiological, histomorphology, and immunohistochemical findings. Histologically, classic adamantinoma is a biphasic tumor characterized by epithelial and osteofibrous components in varying proportions and differentiating patterns. The diagnosis can be confirmed by immunohistochemistry for demonstrating sparse epithelial cell nests when the radiological features are strongly consistent with adamantinoma. This case is highlighted because the epithelial component can lead to a misdiagnosis, particularly when the clinico-radiological features are overlooked. Adamantinoma of long bones has the potential for local recurrence and may metastasize to the lungs, lymph nodes, or other bones. The prognosis is good if early intervention is taken.

9.
Autops Case Rep ; 11: e2021249, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34307216

RESUMEN

Collision tumors have been reported in various organs like the gastrointestinal tract, lung, skin, adrenals, central nervous system, lymph nodes, uterus, but are rarely seen in the ovary. Collision tumors are two histologically distinct neoplasms in the same organ without any intermixture between them. Here we present a case of a collision tumor of the ovary represented by a mucinous cystadenoma and teratoma. It is imperative for a surgical pathologist to correctly diagnose the collision tumor components and differentiate them from mixed tumors as it will dictate the appropriate treatment based on the individual biological aggressiveness of each component.

10.
Autops. Case Rep ; 11: e2021249, 2021. graf
Artículo en Inglés | LILACS | ID: biblio-1153185

RESUMEN

Collision tumors have been reported in various organs like the gastrointestinal tract, lung, skin, adrenals, central nervous system, lymph nodes, uterus, but are rarely seen in the ovary. Collision tumors are two histologically distinct neoplasms in the same organ without any intermixture between them. Here we present a case of a collision tumor of the ovary represented by a mucinous cystadenoma and teratoma. It is imperative for a surgical pathologist to correctly diagnose the collision tumor components and differentiate them from mixed tumors as it will dictate the appropriate treatment based on the individual biological aggressiveness of each component.


Asunto(s)
Humanos , Femenino , Adulto , Teratoma/patología , Cistoadenoma Mucinoso/patología , Neoplasias Ováricas/complicaciones , Diagnóstico Diferencial
11.
Autops. Case Rep ; 11: e2021276, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1249019

RESUMEN

Adamantinoma of the long bones is an exceedingly rare and slow-growing tumor that affects the diaphysis of long bones, particularly the tibia. Based on the pattern of the epithelial cell component and the presence or absence of the osteofibrous dysplasia-like element, several histological variants have been described, such as (i) tubular (the most frequent), (ii) basaloid, (iii) squamous, (iv) spindle variant, (v) osteofibrous dysplasia -like variant, and (vi) Ewing's sarcoma - like adamantinoma (the least frequent). The diagnosis may be challenging since this tumor may be mistakenly interpreted as carcinoma, myoepithelial tumor, osteofibrous dysplasia, and vascular tumor. We report the case of a 41-year-old male who presented with swelling over the right leg associated with pain. The X-ray showed a lytic lesion of the right-sided tibia. The diagnosis of adamantinoma was made based on the clinico-radiological, histomorphology, and immunohistochemical findings. Histologically, classic adamantinoma is a biphasic tumor characterized by epithelial and osteofibrous components in varying proportions and differentiating patterns. The diagnosis can be confirmed by immunohistochemistry for demonstrating sparse epithelial cell nests when the radiological features are strongly consistent with adamantinoma. This case is highlighted because the epithelial component can lead to a misdiagnosis, particularly when the clinico-radiological features are overlooked. Adamantinoma of long bones has the potential for local recurrence and may metastasize to the lungs, lymph nodes, or other bones. The prognosis is good if early intervention is taken.


Asunto(s)
Humanos , Masculino , Adulto , Tibia/patología , Adamantinoma/patología , Diáfisis
12.
Homeopatia Méx ; 89(722): 11-26, 2020. ILUS
Artículo en Español | LILACS, HomeoIndex - Homeopatia | ID: biblio-1352858

RESUMEN

Fundamentos: la hipertensión arterial es el cuarto principal factor de riesgo de muerte e incapacidad, así como el responsable de más de 1.6 millones de fallecimientos en la India. Los informes de casos clínicos, los estudios observacionales y los ECA evidencian los efectos de los medicamentos homeopáticos en la hipertensión. Objetivos: los resultados de este estudio se añaden a la evidencia de la eficacia del uso de los medicamentos homeopáticos individualizados en la hipertensión de estadio I. Materiales y métodos: Se ha realizado un ensayo aleatorizado, simple ciego y controlado por placebo entre octubre de 2013 y marzo de 2018. El parámetro primario fue evaluar los cambios en la presión sistólica (PS) y la presión diastólica (PD) mensualmente durante tres meses. 217 pacientes de los 2,127 pacientes examinados cumplieron los criterios de selección y fueron aleatorizados para recibir un medicamento en potencias Q (o potencias LM) más indicaciones para la modificación del estilo de vida (MEV) (116 pacientes) o bien placebo + MEV (101 pacientes). La modificación del estilo de vida incluyó actividad física y dieta como parte de la pauta terapéutica. El análisis fue de intención de tratamiento. Resultados: Las mediciones ANOVA repetidas entre los grupos mostraron una diferencia estadística significativa (Lambda de Wilks 0.85, F=12.12, dF=213, P=0.0001) tanto en la PS como en la PD a favor de la Homeopatía individualizada. La prueba t independiente post hoc mostró una reducción media significativa de la PS [diferencia media 7.12 mmHg, IC del 95%; CI 4.72 a 9.53, P=0.0001] y un descenso medio de la PD [diferencia media 5.76 mmHg, IC del 95%: 4.18 a 7.23, P=0.0001] a favor del grupo con Homeopatía más MEV. Los medicamentos más utilizados fueron: Sulphur (n=24), Natrium muriaticum (n=21), Lycopodium (n=16), Nux vomica (n=12) y Phosphorus (n=10). Conclusiones: Se ha constatado que la Homeopatía individualizada junto con la MEV fue más eficaz que el placebo junto con la MEV en los pacientes que sufren hipertensión en estadio I. Se precisan más ensayos en un marco estricto. (AU)


Background: Hypertension (HTN) is a leading risk factor for death and disability and responsible for over 1.6 million deaths in India. Clinical case reports, observational studies and randomised controlled trials show the effects of homoeopathic medicine in HTN. Objectives: The results of this study will add to the evidence of effectiveness of individualised homoeopathic medicine in Stage I HTN. Methods: A single-blind, randomised, placebocontrolled trial was undertaken from October 2013 to March 2018. The primary outcome measure was to evaluate the change in systolic blood pressure (SBP) and diastolic blood pressure (DBP) every month for 3 months. Of 2,127 patients screened, 217 patients who fitted the inclusion criteria were randomised to receive either homoeopathic Q potencies (or LM potencies) plus lifestyle modification (LSM)=116 or placebo + LSM=101. LSM included physical activity and diet as part of the treatment regimen. Analysis was by intention to treat. Results: Repeated-measure ANOVA between the groups showed statistically significant difference (Wilk lambda 0.85, F=12.12, df=213, P=0.0001), in both SBP and DBP favouring Individualised Homoeopathy (IH) along with LSM. Post hoc independent t-test showed a significant mean reduction in SBP (mean difference 7.12 mmHg, 95% confidence interval [CI] 4.72-9.53, P=0.0001) and DBP (mean difference 5.76 mmHg, 95% CI: 4.18-7.23, P=0.0001) favouring Homoeopathy plus LSM group. Sulphur (n=24), Natrum muriaticum (n=21), Lycopodium (n=16), Nux vomica (n=12) and Phosphorus (n=10) were the most useful medicines. Conclusion: IH in LM potency along with LSM was found effective over placebo along with LSM in the patients suffering from Stage I HTN. Further trials in rigorous setting are warranted. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Terapéutica Homeopática , Homeopatía , Hipertensión/terapia , Estilo de Vida
13.
Ann Surg ; 269(1): 163-171, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-28799982

RESUMEN

OBJECTIVE: The objective of this study was to compare the long-term survival of open versus thoracoscopic (VATS) lobectomy for early stage non-small-cell lung cancer (NSCLC). BACKGROUND: Data from national studies on long-term survival for VATS versus open lobectomy are limited. METHODS: Outcomes of patients who underwent open versus VATS lobectomy for clinical T1-2, N0, M0 NSCLC in the National Cancer Data Base were evaluated using propensity score matching. RESULTS: The median follow-up of 7114 lobectomies (5566 open and 1548 VATS) was 52.0 months. The VATS approach was associated with a better 5-year survival when compared to the open approach (66.0% vs. 62.5%, P = 0.026). Propensity score matching resulted in 1464 open and 1464 VATS patients who were well matched by 14 common prognostic covariates including tumor size and comorbidities. After propensity score matching, the VATS approach was associated with a shorter median length of stay (5 vs. 6 days, P < 0.001). The VATS approach was not significantly different compared with the open approach with regard to nodal upstaging (11.6% vs 12.3%, P = 0.53), 30-day mortality (1.7% vs 2.3%, P = 0.50) and 5-year survival (66.3% vs 65.8%, P = 0.92). CONCLUSIONS: In this national analysis, VATS lobectomy was used in the minority of patients with stage I NSCLC. VATS lobectomy was associated with shorter length of stay and noninferior long-term survival when compared with open lobectomy. These results support previous findings from smaller single- and multi-institutional studies that suggest that VATS does not compromise oncologic outcomes when used for early-stage lung cancer and suggest the need for broader implementation of VATS techniques.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Neoplasias Pulmonares/mortalidad , Estadificación de Neoplasias , Neumonectomía/métodos , Puntaje de Propensión , Cirugía Torácica Asistida por Video/métodos , Anciano , Biopsia , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Puerto Rico/epidemiología , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Estados Unidos/epidemiología
14.
Int. j. high dilution res ; 18(3/4): 47-62, 2019.
Artículo en Inglés | HomeoIndex - Homeopatia, LILACS | ID: biblio-1050039

RESUMEN

Background Simple and mucopurulent chronic bronchitis (SMCB) is characterized by recurrent mucoid or mucopurulent expectoration in absence of localized suppurative disease. This observational open label study was undertaken to evaluate the effects of homeopathic medicine in SMCB. Methods 1902 patients were screened from 07 centres out of which 1305 were excluded. 597 patients were enrolled as per the inclusion and exclusion criteria. A total of 14 pre-defined homeopathic medicines were shortlisted for prescription after repertorizing the pathological symptoms of SMCB. Outcomes were assessed through chronic bronchitis symptom scale (CBSS) and FEV1/ FVC ratio with spirometry for over a period of two years. Appearance of any change (relief/ worse)/ status quo was immediately followed by placebo/ change in dilution/ change in remedy. Statistical analysis was done using SPSS version 20. Results: 532 patients were analyzed based on the intention to treat principle using last observation carry forward method. Mean CBS score reduced from 29.86±4.5 at baseline to 12.33±7.6 at completion of 2 years. Repeated measures ANOVA, at time points 0 (baseline), 3, 6, 9, 12 ,15, 18, 21 and 24 months, showed significant reduction in CBS scores [Wilk's Lambda 0.104, F=564, df 524; p=00001]. The FEV1 and FEV1/FVC was maintained within normal limits. 86% prescriptions included Lycopodium, Arsenicum album, Pulsatilla, Phosphorus, Stannum metallicum, Calcarea carbonica, Silicea, Bryonia alba. Conclusion: The result suggests effectiveness of homeopathic treatment in early years of SCMB patients. Controlled trials are warranted. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Bronquitis Crónica/terapia , Homeopatía , Pulsatilla nigricans/uso terapéutico , Arsenicum Album/uso terapéutico , Calcarea Carbonica/uso terapéutico , Lycopodium clavatum/uso terapéutico , Silicea Terra/uso terapéutico , Stannum Metallicum/uso terapéutico , Bryonia
15.
Braz. arch. biol. technol ; Braz. arch. biol. technol;58(5): 667-675, tab, graf
Artículo en Inglés | LILACS | ID: lil-764483

RESUMEN

ABSTRACTThe present investigation was aimed to detect the specific polypeptide(s) appeared during the sequential stages of differentiation. Among different explants, only nodal explants showed good results for callusing. Depending on the fresh and dry weight, best callus growth was observed on MS medium supplemented with NAA (2.5 mg/L) inDioscorea alata and 2, 4-D (2.0 mg/L) inD. deltoidea, respectively. This callus was used for the regeneration. Roots differentiation was observed on MS medium + NAA (2.0 mg/L) + IBA (0.5 mg/L) and shoots on MS medium + BAP (2.0 mg/L) + NAA (0.5 mg/L) in D. alata while in D. deltoidea, roots on RT medium + IAA (1.0 mg/L) and shoots on RT medium + BAP (1.0 mg/L) + NAA (0.5 mg/L). Continuous decrease was seen in the total soluble protein during the differentiation inD. alatawhereas inD. deltoidea, the protein content decreased upto initiation stage. Four root specific polypeptides (MW 25.56, 24.35, 19.13 and 18.2 kDa) and three shoot specific polypeptides (MW 53.7, 25.12 and 19.13 kDa) were synthesized during the differentiation inD. alata. Similarly, two root specific (MW 33.9 and 31.69 kDa) and one shoot specific (MW 16.98 kDa) polypeptide band were appeared during differentiation in D. deltoidea.

16.
PLoS One ; 7(1): e30356, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22291940

RESUMEN

Chagas disease is caused by infection with the intracellular protozoan parasite Trypanosoma cruzi. At present, nifurtimox and benznidazole, both compounds developed empirically over four decades ago, represent the chemotherapeutic arsenal for treating this highly neglected disease. However, both drugs present variable efficacy depending on the geographical area and the occurrence of natural resistance, and are poorly effective against the later chronic stage. As a part of a search for new therapeutic opportunities to treat chagasic patients, pre-clinical studies were performed to characterize the activity of a novel arylimidamide (AIA--DB1831 (hydrochloride salt) and DB1965 (mesylate salt)) against T. cruzi. These AIAs displayed a high trypanocidal effect in vitro against both relevant forms in mammalian hosts, exhibiting a high selectivity index and a very high efficacy (IC(50) value/48 h of 5-40 nM) against intracellular parasites. DB1965 shows high activity in vivo in acute experimental models (mouse) of T. cruzi, showing a similar effect to benznidazole (Bz) when compared under a scheme of 10 daily consecutive doses with 12.5 mg/kg. Although no parasitological cure was observed after treating with 20 daily consecutive doses, a combined dosage of DB1965 (5 mg/kg) with Bz (50 mg/kg) resulted in parasitaemia clearance and 100% animal survival. In summary, our present data confirmed that aryimidamides represent promising new chemical entities against T. cruzi in therapeutic schemes using the AIA alone or in combination with other drugs, like benznidazole.


Asunto(s)
Amidas/uso terapéutico , Amidinas/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Mesilatos/uso terapéutico , Pirimidinas/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Amidas/efectos adversos , Amidas/farmacología , Amidinas/efectos adversos , Amidinas/farmacología , Animales , Antiprotozoarios/efectos adversos , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Células Cultivadas , Enfermedad de Chagas/mortalidad , Enfermedad de Chagas/patología , Evaluación Preclínica de Medicamentos , Femenino , Masculino , Mesilatos/efectos adversos , Mesilatos/farmacología , Ratones , Modelos Biológicos , Nivel sin Efectos Adversos Observados , Pirimidinas/efectos adversos , Pirimidinas/farmacología , Resultado del Tratamiento , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/fisiología
17.
Parasitology ; 138(14): 1863-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21902869

RESUMEN

The present study aimed to determine the in vitro biological efficacy and selectivity of 7 novel AIAs upon bloodstream trypomastigotes and intracellular amastigotes of Trypanosoma cruzi. The biological activity of these aromatic compounds was assayed for 48 and 24 h against intracellular parasites and bloodstream forms of T. cruzi (Y strain), respectively. Additional assays were also performed to determine their potential use in blood banks by treating the bloodstream parasites with the compounds diluted in mouse blood for 24 h at 4°C. Toxicity against mammalian cells was evaluated using primary cultures of cardiac cells incubated for 24 and 48 h with the AIAs and then cellular death rates were determined by MTT colorimetric assays. Our data demonstrated the outstanding trypanocidal effect of AIAs against T. cruzi, especially DB1853, DB1862, DB1867 and DB1868, giving IC50 values ranging between 16 and 70 nanomolar against both parasite forms. All AIAs presented superior efficacy to benznidazole and some, such as DB1868, also demonstrated promising activity as a candidate agent for blood prophylaxis. The excellent anti-trypanosomal efficacy of these novel AIAs against T. cruzi stimulates further in vivo studies and justifies the screening of new analogues with the goal of establishing a useful alternative therapy for Chagas disease.


Asunto(s)
Amidas/farmacología , Enfermedad de Chagas/tratamiento farmacológico , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Amidas/química , Amidas/aislamiento & purificación , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Enfermedad de Chagas/parasitología , Concentración 50 Inhibidora , Ratones , Miocitos Cardíacos , Nitroimidazoles/farmacología , Pruebas de Sensibilidad Parasitaria , Tripanocidas/química , Tripanocidas/aislamiento & purificación
18.
Exp Parasitol ; 123(1): 73-80, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19520077

RESUMEN

Chagas disease remains a serious public health problem in several Latin American countries. New chemotherapy is urgently needed since current drugs are limited in efficacy and exhibit undesirable side effects. Aromatic diamidines and analogs are well known anti-parasitic agents and in this study, we have evaluated the in vitro trypanocidal effect of several different heterocyclic cationic compounds, including diamidines (DB1195, DB1196 and DB1345), a monoamidine (DB824), an arylimidamide (DB613A) and a guanylhydrazone (DB1080) against amastigotes and bloodstream trypomastigotes of Trypanosoma cruzi, the etiological agent of Chagas disease. Our present findings showed that all compounds exerted, at low-micromolar doses, a trypanocidal effect upon both intracellular parasites and bloodstream trypomastigotes of T. cruzi. The activity of DB1195, DB1345, DB824 and DB1080 against bloodstream forms was reduced when these compounds were assayed in the presence of mouse blood possibly due to their association with plasma constituents and/or due to metabolic instability of the compounds. However, trypanocidal effects of DB613A and DB1196 were not affected by plasma constituents, suggesting their potential application in the prophylaxis of banked blood. In addition, potency and selectivity of DB613A, towards intracellular parasites, corroborate previous results that demonstrated the highly promising activity of arylimidamides against this parasite, which justify further studies in experimental models of T. cruzi infection.


Asunto(s)
Amidinas/farmacología , Compuestos Heterocíclicos/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Chlorocebus aethiops , Relación Dosis-Respuesta a Droga , Concentración 50 Inhibidora , Pruebas de Sensibilidad Parasitaria , Células Vero
19.
J Antimicrob Chemother ; 58(3): 610-4, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16854954

RESUMEN

OBJECTIVES: Aromatic diamidines have been successfully used to combat a wide range of parasites that cause important human infections. One such compound is furamidine (DB75) and we recently reported that one of its analogues, an N-phenyl analogue (DB569), exhibits higher trypanocidal dose and time-dependent effects against different forms of Trypanosoma cruzi as compared with DB75. Our present aim was to investigate the efficacy of DB569 in a T. cruzi mouse model. METHODS: The trypanocidal activity of the compound was evaluated by clinical, parasitological, histopathological and biochemical investigations. RESULTS: Treatment with DB569 significantly reduced cardiac parasitism, partially increased the survival rates of mice and lowered the levels of alanine aminotransferase and creatinine indicating a protective role against renal and hepatic lesions caused by the parasite infection. CONCLUSIONS: Altogether, the data support the potential effect of this class of compounds against T. cruzi and motivate the screening of new diamidines for efficacy against Chagas' disease.


Asunto(s)
Benzamidinas/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Tripanocidas/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Alanina Transaminasa/metabolismo , Animales , Benzamidinas/administración & dosificación , Benzamidinas/química , Creatina Quinasa/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Corazón/parasitología , Masculino , Ratones , Estructura Molecular , Factores de Tiempo , Tripanocidas/administración & dosificación , Tripanocidas/química , Trypanosoma cruzi/crecimiento & desarrollo
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