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1.
BMC Gastroenterol ; 24(1): 71, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355409

RESUMEN

BACKGROUND: Current scientific evidence has pointed out the relevance of hemostatic products for improving clinical outcomes in liver trauma, including increased survival rates and reductions in bleeding-related complications. The purpose of this study was to compare the use of the gelatin-thrombin flowable (Flowable) versus the standard technique of Packing in a new experimental liver injury model. METHODS: Twenty-four swine were prospectively randomized to receive either Flowable or standard packing technique. We used a novel severe liver injury model, in which the middle and left suprahepatic veins were selectively injured, causing an exsanguinating hemorrhage. The main outcome measure was the percentage of lost blood volume. RESULTS: The median total percentage of total blood volume per animal lost, from injury to minute 120, was significantly lower in the Flowable group (15.2%; interquartile range: 10.7-46.7%) than in the Packing group (64.9%; Interquartile range: 53.4-73.0%) (Hodges-Lehmann median difference: 41.1%; 95% CI: 18.9-58.0%, p = 0.0034). The 24-hour survival rate was significantly higher in the Flowable group (87.0%) than in the Packing group (0.0%) (Hazard ratio (HR) 0.08; 95% confidence interval 0.102 to 0.27; p < 0.0001). Mean-arterial pressure was significantly lower at minute 60 and 120 in the Flowable group than in the packing group (p = 0.0258 and p = 0.0272, respectively). At minute 120, hematocrit was higher in the Flowable than in the packing group (Hodges-Lehmann median difference: 5.5%; 95%CI: 1.0 to11.0, p = 0.0267). Finally, the overall-surgical-procedure was significantly shorter with Flowable than with Packing (Hodges-Lehmann median difference: 39.5 s, 95% CI: 25.0 to 54.0 s, p = 0.0004). CONCLUSIONS: The use of the Flowable was more effective in achieving hemostasis, reducing blood loss, and improving survival rates than standard packing in a severe porcine-liver bleeding model.


Asunto(s)
Hemostáticos , Trombina , Animales , Porcinos , Trombina/uso terapéutico , Gelatina/uso terapéutico , Esponja de Gelatina Absorbible/uso terapéutico , Hemostáticos/uso terapéutico , Hemorragia/terapia , Hígado/lesiones
2.
Childs Nerv Syst ; 40(2): 303-319, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37819508

RESUMEN

PURPOSE: Coccidioidal meningitis (CM) is an uncommon disease frequently misdiagnosed. Neuroimaging and mortality are not considered in detail in previous pediatric CM series. Our objective is to evaluate outcome of pediatric neurococcidiomycosis in relation to neuroimaging findings. METHODS: We performed a prospective, observational, cross-sectional study in children with hydrocephalus and CM treated at Specialties Hospital in Torreon, Mexico (between 2015 and 2020). The outcome was evaluated by Hydrocephalus Outcome Questionnaire (HOQ) and the modified Rankin Scale (mRS). Follow-up was established at the first shunt surgery and survival since CM diagnosis confirmation. Neuroimaging was analyzed in relation to clinical data, outcome and survival. Kaplan-Meier analysis was performed with IBM-SPSS-25. RESULTS: Ten pediatric cases with CM and hydrocephalus were reported. Aged 6-228 months, 60% were female. Mean number of surgeries was 4.3 SD ± 3 (range 1-15). Asymmetric hydrocephalus was the most common neuroimaging finding (70%), followed by cerebral vasculitis (20%) and isolated fourth ventricle (IFV) (20%). The mean HOQ overall score was 0.338 SD ± 0.35. A minimum follow-up of 18 months was reported. Mean survival was 13.9 SD ± 6.15 months (range 3-24). Poor survival was correlated with asymmetric hydrocephalus (p = 0.335), cerebral vasculitis (p = 0.176), IFV (p < 0.001), bacterial superinfection (p = 0.017), lower mRS scores at hospital discharge (p = 0.017) and during follow-up (p = 0.004). The mortality rate was 20%. CONCLUSIONS: We report the largest series in Latin America of pediatric CM and hydrocephalus. Asymmetric hydrocephalus, IFV and cerebral vasculitis are complications that increase mortality and must be early diagnosed for a timely surgical and medical treatment. HOQ and mRS could be alternative scales to evaluate outcome in these patients. After a long follow-up (18 months), survival remained poor after diagnosis confirmation in our series.


Asunto(s)
Hidrocefalia , Vasculitis del Sistema Nervioso Central , Niño , Femenino , Humanos , Masculino , Estudios Transversales , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/etiología , Hidrocefalia/cirugía , Estudios Prospectivos , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
3.
Chimia (Aarau) ; 75(5): 376-386, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34016232

RESUMEN

Nanocrystals (NCs) are complex systems that offer a superior level of detailed engineering at the atomic level. The large number of novel and revolutionary applications have made nanocrystals of special interest. In particular oxide perovskites are one of the most widely investigated family of materials in solid-state chemistry, especially for their ferroelectric and superconducting properties. In addition to these well-known properties, perovskites show good electrical conductivity (close to metals), ion conductivity and mixed ionic-electronic conductivity. In that sense, controlled synthesis of nanomaterials with special care over size and shape are essential in many fields of science and technology. Although it is well-known that physical methods deliver excellent quality nanomaterials, their high production cost has increased the interest to more affordable alternative chemical processes. In this review, we focus on the preparation of sub-10 nm oxide perovskite nanocrystals and the main strategies used to control the final properties of the obtained products. In the second part, we present the methods available for nanocrystal solutions processing together with the most remarkable applications foreseen.

4.
Int J Mol Sci ; 20(2)2019 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-30634573

RESUMEN

Voltage-dependent potassium channels (Kv channels) are crucial regulators of cell excitability that participate in a range of physiological and pathophysiological processes. These channels are molecular machines that display a mechanism (known as gating) for opening and closing a gate located in a pore domain (PD). In Kv channels, this mechanism is triggered and controlled by changes in the magnitude of the transmembrane voltage sensed by a voltage-sensing domain (VSD). In this review, we consider several aspects of the VSD⁻PD coupling in Kv channels, and in some relatives, that share a common general structure characterized by a single square-shaped ion conduction pore in the center, surrounded by four VSDs located at the periphery. We compile some recent advances in the knowledge of their architecture, based in cryo-electron microscopy (cryo-EM) data for high-resolution determination of their structure, plus some new functional data obtained with channel variants in which the covalent continuity between the VSD and PD modules has been interrupted. These advances and new data bring about some reconsiderations about the use of exclusively a classical electromechanical lever model of VSD⁻PD coupling by some Kv channels, and open a view of the Kv-type channels as allosteric machines in which gating may be dynamically influenced by some long-range interactional/allosteric mechanisms.


Asunto(s)
Activación del Canal Iónico , Canales de Potasio con Entrada de Voltaje/química , Canales de Potasio con Entrada de Voltaje/metabolismo , Relación Estructura-Actividad Cuantitativa , Regulación Alostérica , Animales , Microscopía por Crioelectrón , Humanos , Modelos Moleculares , Conformación Proteica , Dominios Proteicos
5.
Pflugers Arch ; 470(7): 1069-1085, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29572566

RESUMEN

Voltage-dependent KCNH family potassium channel functionality can be reconstructed using non-covalently linked voltage-sensing domain (VSD) and pore modules (split channels). However, the necessity of a covalent continuity for channel function has not been evaluated at other points within the two functionally independent channel modules. We find here that by cutting Kv11.1 (hERG, KCNH2) channels at the different loops linking the transmembrane spans of the channel core, not only channels split at the S4-S5 linker level, but also those split at the intracellular S2-S3 and the extracellular S3-S4 loops, yield fully functional channel proteins. Our data indicate that albeit less markedly, channels split after residue 482 in the S2-S3 linker resemble the uncoupled gating phenotype of those split at the C-terminal end of the VSD S4 transmembrane segment. Channels split after residues 514 and 518 in the S3-S4 linker show gating characteristics similar to those of the continuous wild-type channel. However, breaking the covalent link at this level strongly accelerates the voltage-dependent accessibility of a membrane impermeable methanethiosulfonate reagent to an engineered cysteine at the N-terminal region of the S4 transmembrane helix. Thus, besides that of the S4-S5 linker, structural integrity of the intracellular S2-S3 linker seems to constitute an important factor for proper transduction of VSD rearrangements to opening and closing the cytoplasmic gate. Furthermore, our data suggest that the short and probably rigid characteristics of the extracellular S3-S4 linker are not an essential component of the Kv11.1 voltage sensing machinery.


Asunto(s)
Canal de Potasio ERG1/metabolismo , Activación del Canal Iónico/fisiología , Dominios Proteicos/fisiología , Animales , Cisteína/metabolismo , Citoplasma/metabolismo , Humanos , Potenciales de la Membrana/fisiología , Oocitos/metabolismo , Xenopus laevis/metabolismo
6.
Pflugers Arch ; 470(3): 517-536, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29270671

RESUMEN

Kv11.1 (hERG, KCNH2) is a voltage-gated potassium channel crucial in setting the cardiac rhythm and the electrical behaviour of several non-cardiac cell types. Voltage-dependent gating of Kv11.1 can be reconstructed from non-covalently linked voltage sensing and pore modules (split channels), challenging classical views of voltage-dependent channel activation based on a S4-S5 linker acting as a rigid mechanical lever to open the gate. Progressive displacement of the split position from the end to the beginning of the S4-S5 linker induces an increasing negative shift in activation voltage dependence, a reduced z g value and a more negative ΔG 0 for current activation, an almost complete abolition of the activation time course sigmoid shape and a slowing of the voltage-dependent deactivation. Channels disconnected at the S4-S5 linker near the S4 helix show a destabilization of the closed state(s). Furthermore, the isochronal ion current mode shift magnitude is clearly reduced in the different splits. Interestingly, the progressive modifications of voltage dependence activation gating by changing the split position are accompanied by a shift in the voltage-dependent availability to a methanethiosulfonate reagent of a Cys introduced at the upper S4 helix. Our data demonstrate for the first time that alterations in the covalent connection between the voltage sensor and the pore domains impact on the structural reorganizations of the voltage sensor domain. Also, they support the hypothesis that the S4-S5 linker integrates signals coming from other cytoplasmic domains that constitute either an important component or a crucial regulator of the gating machinery in Kv11.1 and other KCNH channels.


Asunto(s)
Canal de Potasio ERG1/metabolismo , Activación del Canal Iónico , Sustitución de Aminoácidos , Animales , Cisteína/genética , Canal de Potasio ERG1/química , Canal de Potasio ERG1/genética , Humanos , Dominios Proteicos , Xenopus
7.
Pflugers Arch ; 467(8): 1747-56, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25224286

RESUMEN

The N-terminal-most N-tail of the human ether-à-go-go-related gene (hERG) potassium channel is a crucial modulator of deactivation through its interactions with the S4-S5 loop and/or the C-linker/cNBD, leading to a stabilization of the channel's open state. Not only the N-terminal, but also the initial C-terminal region of the channel can modulate the transitions between the open and closed states either by direct or by indirect/allosteric interactions with the gating machinery. However, while a physical proximity of the N-tail to the gating machinery has been demonstrated in the closed state, data about their possible interaction in other channel conformations have been lacking. Using a site-directed cysteine mutagenesis and disulfide chemistry approach, we present here evidence that a physical proximity between the N-tail and the gating-related structures can also exist in channels held between pulses in the open/inactive state, highlighting the physiological and functional relevance of the direct interactions between the N-terminal tail and the S4-S5 loop and/or C-linker structures for modulation of channel.


Asunto(s)
Canales de Potasio Éter-A-Go-Go/metabolismo , Activación del Canal Iónico , Animales , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go/química , Canales de Potasio Éter-A-Go-Go/genética , Humanos , Potenciales de la Membrana , Mutagénesis Sitio-Dirigida , Mutación , Oocitos , Conformación Proteica , Estructura Terciaria de Proteína , Relación Estructura-Actividad , Factores de Tiempo , Xenopus laevis
8.
Biochem Biophys Res Commun ; 453(4): 754-60, 2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25305496

RESUMEN

Two pore domain potassium (K2P) channels are mostly present in the central nervous system (CNS) where they play important roles in modulating neuronal excitability. K2P channels give rise to background K(+) currents (IKSO) a key component in setting and maintaining the resting membrane potential in excitable cells. Here, we studied the expression and relative abundances of K2P channels in cerebellar granule neurons (CGNs), combining molecular biology, electrophysiology and immunologic techniques. The CGN IKSO was very sensitive to external pH, as previously reported. Quantitative determination of mRNA expression level demonstrated the existence of an accumulation pattern of transcripts in CGN that encode K2P9>K2P1>K2P3>K2P18>K2P2=K2P10>K2P4>K2P5 subunits. The presence of the major K2P subunits expressed was then confirmed by Western blot and immunofluorescence analysis, demonstrating robust expression of K2P1 (TWIK-1), K2P3 (TASK-1), K2P9 (TASK-3) and K2P18 (TRESK) channel protein. Based, on these results, it is concluded that K2P1, -3, -9 and -18 subunits represent the majority component of IKSO current in CGN.


Asunto(s)
Cerebelo/citología , Cerebelo/metabolismo , Neuronas/metabolismo , Canales de Potasio de Dominio Poro en Tándem/química , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Canales de Potasio/química , Canales de Potasio/metabolismo , Animales , Células Cultivadas , Regulación de la Expresión Génica/fisiología , Activación del Canal Iónico/fisiología , Porosidad , Canales de Potasio/clasificación , Estructura Terciaria de Proteína , Ratas , Ratas Sprague-Dawley
9.
Biochem J ; 451(3): 463-74, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23418776

RESUMEN

The characteristic gating properties of the HERG [human eag (ether-a-go-go)-related gene] potassium channel determine its contribution to cardiac repolarization and in setting the electrical behaviour of a variety of cells. In the present study we analysed, using a site-directed cysteine and disulfide chemistry approach, whether the eag/PAS (Per/Arnt/Sim) and proximal domains at the HERG N-terminus exert a role in controlling the access of the N-terminal flexible tail to its binding site in the channel core for interaction with the gating machinery. Whereas the eag/PAS domain is necessary for disulfide bridging, plus the cysteine residues introduced at positions 3 and 542 of the HERG sequence, the presence of the proximal domain seems to be dispensable. The state-dependent formation of a disulfide bridge between Cys3 and an endogenous cysteine residue at position 723 in the C-terminal C-linker suggests that the N-terminal tail of HERG can also get into close proximity with the C-linker structures located at the bottom of helix S6. Therefore the intrinsic flexibility of the N-tail and its proximity to both the S4-S5 loop and the C-linker may dynamically contribute to the modulation of HERG channel gating.


Asunto(s)
Cisteína/química , Canales de Potasio Éter-A-Go-Go/química , Potenciales de la Membrana/fisiología , Oocitos/metabolismo , Animales , Sitios de Unión , Cisteína/genética , Cisteína/metabolismo , Disulfuros/química , Canales de Potasio Éter-A-Go-Go/genética , Canales de Potasio Éter-A-Go-Go/metabolismo , Humanos , Activación del Canal Iónico , Microinyecciones , Mutagénesis Sitio-Dirigida , Oocitos/citología , Oxidación-Reducción , Técnicas de Placa-Clamp , Plásmidos , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Relación Estructura-Actividad , Xenopus laevis
10.
Ginecol Obstet Mex ; 82(6): 397-400, 2014 Jun.
Artículo en Español | MEDLINE | ID: mdl-25016900

RESUMEN

Ovarian small cell pulmonary type carcinoma is a rare and aggressive tumor with higher incidence in young women. Multidisciplinary treatment seems to increase survival in a small number of cases. We present the case of a woman diagnosed with this type of tumor of small cells, their clinical evolution and the treatment he received.


Asunto(s)
Carcinoma de Células Pequeñas/patología , Neoplasias Ováricas/patología , Adulto , Carcinoma de Células Pequeñas/terapia , Femenino , Humanos , Comunicación Interdisciplinaria , Neoplasias Ováricas/terapia
11.
Heliyon ; 10(7): e28555, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38623248

RESUMEN

Introduction: Previous studies have reported a correlation between a high-grade CMV-infection and an unfavorable prognosis in glioblastoma (GB). Coversely, epilepsy has been associated with a more favorable outcome in GB patients. Despites epilepsy and CMV share similar molecular mechanisms in GB tumoral microenvironment, the correlation between Tumor-Related-Epilepsy (TRE) and CMVinfection remains unexplored. The aim of our study is to examine the correlation between the dregree of CMV infection and seizure types on the survival of TRE Adult-type-diffuse-glioma. To achieve this objective, we conducted a comprehensive literature review to assess our results regarding previous publications. Methods: We conducted a retrospective-observational study on TRE Adult-type-diffuse-gliomas treated at a single center in Mexico from 2010 to 2018. Tumor tissue and cDNA were analyzed by immunochemistry (IHC) for CMV (IE and LA antigens) at the Karolinska Institute in Sweden, and RT-PCR for CMV-gB in Torreon Mexico, respectively. Bivariate analysis (X2-test) was performed to evaluate the association between subtypes of Adult-type-diffuse-glioma (IDH-mut grade 4 astrocytoma vs. IDH-wt glioblastoma) and the following variables: type of hemispheric involvement (mesial vs. neocortical involvement), degree of CMV infection (<25%vs. >25% infected-tumoral cells) and seizure types [Focal awareness, focal impaired awareness, and FBTCS]. Kaplan Meier and Cox analyses were performed to determine the risk, p < 0.05 was considered statistically significant. Results: Sixty patients with TRE Adult type diffuse gliomas were included (80% IDH-wt glioblastoma and 20% IDH-mut grade 4astrocytomas). The mean age was 61.5 SD ± 18.4, and 57% were male. Fifty percent of the patients presented with mesial involvement of the hemysphere. Seizure types included focal awareness (15%), focal impaired awareness (43.3%), and FBTCS (41.7%). Ninety percent of cases were treated with Levetiracetam and 33.3% presented Engel-IA postoperative seizure control. More than 90% of samples were positive for CMV-immunohistochemistry (IHC). However, all cDNA analyzed by RT-PCR return negative results. The median of overall survival (OS) was 15 months. High-grade CMV-IE infection (14 vs. 25 months, p<0.001), mesial involvement (12 vs. 18 months, p<0.001), and FBTCS were associated with worse OS (9 vs.18 months for non-FBTCS). Multivariate analysis demonstrated that high-grade CMV infection (HR = 3.689, p=0.002) and FBTCS (HR=7.007, p<0.001) were independent unfavorable survival factors. Conclusions: CMV induces a proinflammatory tumoral microenvironment that contributes to the developmet of epilepsy. Tumor progression could be associated not only with a higher degree of CMV infection but also to epileptogenesis, resulting in a seizure phenotype chracterized by FBTCS and poor survival outcomes. This study represents the first survival analysis in Latin America to include a representative sample of TRE Adult-type diffuse gliomas considering CMV-infection-degree and distinguishing features (such as FBTCS) that might have potential clinical relevance in this group of patients. Further prospective studies are required to validate these results.

12.
MethodsX ; 11: 102362, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37736150

RESUMEN

Some hepatic wound models have been developed in pigs with the aim of reproducing liver injury; however, the wound shape, severity, and outcome differ among them. The novel injury profile employed in this study differed from that used elsewhere for standardized, repeatable, reproducible, incising-penetrating, vascular, and severe injury in swine. It is made with a cutting object that penetrates deep into the hepatic parenchyma, always affecting the two suprahepatic veins at the point where they merge into the common trunk. The primary outcome was reproducibility and replicability of the surgical method. The secondary outcome was the analysis of some variables (blood loss, survival, and flow) to validate the model. •This novel method of liver injury provides a liver injury with the following characteristics: standardized, incise-penetrated, deep, bloody, and severe.•This model can be used for research (trauma, hepato-bilio-pancreatic, pharmaceutical) and training (damage control surgery).•Method name: Incising-Penetrating, Vascular and Severe Liver Injury Model in Swine.

13.
J Biol Chem ; 286(21): 19065-75, 2011 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-21474444

RESUMEN

Potassium channels encoded by the human ether-à-go-go-related gene (hERG) contribute to cardiac repolarization as a result of their characteristic gating properties. The hERG channel N terminus acts as a crucial determinant in gating. It is also known that the S4-S5 linker couples the voltage-sensing machinery to the channel gate. Moreover, this linker has been repeatedly proposed as an interaction site for the distal portion of the N terminus controlling channel gating, but direct evidence for such an interaction is still lacking. In this study, we used disulfide bond formation between pairs of engineered cysteines to demonstrate the close proximity between the beginning of the N terminus and the S4-S5 linker. Currents from channels with introduced cysteines were rapidly and strongly attenuated by an oxidizing agent, this effect being maximal for cysteine pairs located around amino acids 3 and 542 of the hERG sequence. The state-dependent modification of the double-mutant channels, but not the single-cysteine mutants, and the ability to readily reverse modification with the reducing agent dithiothreitol indicate that a disulfide bond is formed under oxidizing conditions, locking the channels in a non-conducting state. We conclude that physical interactions between the N-terminal-most segment of the N terminus and the S4-S5 linker constitute an essential component of the hERG gating machinery, thus providing a molecular basis for previous data and indicating an important contribution of these cytoplasmic domains in controlling its unusual gating and hence determining its physiological role in setting the electrical behavior of cardiac and other cell types.


Asunto(s)
Canales de Potasio Éter-A-Go-Go/metabolismo , Activación del Canal Iónico/fisiología , Sustitución de Aminoácidos , Animales , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go/genética , Humanos , Mutación Missense , Estructura Terciaria de Proteína , Xenopus laevis
14.
Pflugers Arch ; 463(5): 685-702, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22415214

RESUMEN

While the thyrotropin-releasing hormone (TRH) effect of raising intracellular Ca(2+) levels has been shown to rely on G(q/11) and PLC activation, the molecular mechanisms involved in the regulation of ERG K(+) channels by TRH are still partially unknown. We have analysed the effects of ßγ scavengers, Akt/PKB inactivation, and TRH receptor (TRH-R) overexpression on such regulation in native and heterologous expression cell systems. In native rat pituitary GH(3) cells ß-ARK/CT, Gα(t), and phosducin significantly reduced TRH inhibition of rERG currents, whereas in HEK-H36/T1 cells permanently expressing TRH-R and hERG, neither of the ßγ scavengers affected the TRH-induced shift in V (1/2). Use of specific siRNAs to knock Akt/PKB expression down abolished the TRH effect on HEK-H36/T1 cell hERG, but not on rERG from GH(3) cells. Indeed, wortmannin or long insulin pretreatment also blocked TRH regulation of ERG currents in HEK-H36/T1 but not in GH(3) cells. To determine whether these differences could be related to the amount of TRH-Rs in the cell, we studied the TRH concentration dependence of the Ca(2+) and ERG responses in GH(3) cells overexpressing the receptors. The data indicated that independent of the receptor number additional cellular factor(s) contribute differently to couple the TRH-R to hERG channel modulation in HEK-H36/T1 cells. We conclude that regulation of ERG currents by TRH and its receptor is transduced in GH(3) and HEK-H36/T1 cell systems through common and different elements, and hence that the cell type influences the signalling pathways involved in the TRH-evoked responses.


Asunto(s)
Calcio/metabolismo , Canales de Potasio Éter-A-Go-Go/metabolismo , Hormona Liberadora de Tirotropina/metabolismo , Proteínas Quinasas Dependientes de 3-Fosfoinosítido , Animales , Sitios de Unión , Células Cultivadas , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Subunidades beta de la Proteína de Unión al GTP/metabolismo , Subunidades gamma de la Proteína de Unión al GTP/metabolismo , Humanos , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Receptores de Hormona Liberadora de Tirotropina/metabolismo , Transducción de Señal
15.
Ginecol Obstet Mex ; 80(12): 777-82, 2012 Dec.
Artículo en Español | MEDLINE | ID: mdl-23405509

RESUMEN

BACKGROUND: Breast cancer occupies the chief place in incidence after the cervix. This gland sarcomas are rare with less than 1% at this location. Its diagnosis is difficult and its evolution is aggressive. Primary breast osteogenic sarcomas are a subset of lower frequency so that their behavior, evolution, prognosis ytratamiento no much experience and often are diagnosed as benign tumors. CASE REPORT: We report the case of a woman of 59 years which initially arose from a tumor in the right breast was performed with tru-cut biopsy with inconclusive results, using the tumor 7 months after the presence of a multilobulated solid tumor 20 cm, tumor compatible with mammography Phylodes (BIRADS 2). It was decided to perform right total mastectomy and pectoral muscle resection reconstruction with latissimus dorsi more and histochemical review pathology diagnosed with malignant mesenchymal neoplasm, osteosarcoma osteoblast osteoclast type and complemented the treatment with radiotherapy and chemotherapy. The prognosis is poor because the five-year survival is less than 40%. CONCLUSION: In the fast-growing breast tumors and large mammographic calcifications with signs and antecedentesde irradiation, trauma and Phyllodes tumor must be aware of this disease and that early diagnosis improves survival. In the surgical treatment of axillary dissection is not indicated and adjuvant treatment with radiotherapy and chemotherapy.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Sarcoma/diagnóstico , Femenino , Humanos , Persona de Mediana Edad
16.
J Vis Exp ; (190)2022 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-36622023

RESUMEN

Focused shock waves have emerged as a highly effective noninvasive therapeutic option for the treatment of calcific tendinitis of the shoulder. There are three types of focused shock wave generators: electrohydraulic, electromagnetic, and piezoelectric. According to our literature search, there are no reports of results with the use of single-crystal piezoelectric generators in calcific tendinitis of the shoulder. In a consecutive retrospective series of 23 patients with Gärtner type I and II calcifications of the rotator cuff, we performed three applications of high-energy piezoelectric focused waves (4,000 pulses per session with a frequency of 6 Hz). At the final follow-up (average of 14 months), 82.6% of the cases showed complete resorption of the calcification in radiographic controls. In 8.7% of the cases, partial disappearance of the calcification was achieved, and in the remaining 8.7% there were no significant changes. Single-crystal piezoelectric generators have a success rate comparable to those already reported with electrohydraulic and electromagnetic devices.


Asunto(s)
Calcinosis , Tendinopatía , Humanos , Manguito de los Rotadores/diagnóstico por imagen , Manguito de los Rotadores/cirugía , Estudios Retrospectivos , Dolor de Hombro/terapia , Tendinopatía/terapia , Protocolos Clínicos , Calcinosis/terapia
17.
Microbiol Spectr ; 10(3): e0026922, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35506680

RESUMEN

The antimicrobial properties of photocatalysts have long been studied. However, most of the available literature describes their antibacterial properties, while knowledge of their antiviral activity is rather scarce. Since the outset of the coronavirus disease 2019 (COVID-19) pandemic, an increasing body of research has suggested their antiviral potential and highlighted the need for further research in this area. In this study, we investigated the virucidal properties of a commercial TiO2-coated photocatalytic glass against a model human coronavirus. Our findings demonstrate that the TiO2-coated glass consistently inactivates coronaviruses upon contact under daylight illumination, in a time-dependent manner. A 99% drop in virus titer was achieved after 3.9 h. The electron micrographs of virus-covered TiO2-glass showed a reduced number of virions compared to control glass. Morphological alterations of TiO2-exposed viruses included deformation, disruption of the viral envelope, and virion ghosts, endorsing the application of this material in the construction of protective elements to mitigate the transmission of viruses. To the best of our knowledge, this is the first report showing direct visual evidence of human coronaviruses being damaged and morphologically altered following exposure to this photocatalyst. IMPORTANCE Surface contamination is an important contributor to SARS-CoV-2 spread. The use of personal protective elements and physical barriers (i.e., masks, gloves, and indoor glass separators) increases safety and has proven invaluable in preventing contagion. Redesigning these barriers so that the virus cannot remain infectious on them could make a difference in COVID-19 epidemiology. The introduction of additives with virucidal activity could potentiate the protective effects of these barriers to serve not only as physical containment but also as virus killers, reducing surface contamination after hand touch or aerosol deposition. We performed in-depth analysis of the kinetics of photocatalysis-triggered coronavirus inactivation on building glass coated with TiO2. This is the first report showing direct visual evidence (electron microscopy) of coronaviruses being morphologically damaged following exposure to this photocatalyst, demonstrating the high potential of this material to be incorporated into daily-life high-touch surfaces, giving them an added value in decelerating the virus spread.


Asunto(s)
COVID-19 , Virus , Antivirales/farmacología , COVID-19/prevención & control , Humanos , Pandemias , SARS-CoV-2
18.
World Neurosurg ; 158: e393-e415, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34763105

RESUMEN

BACKGROUND: Discrimination, abuse, and mistreatment are prevailing problems reported in neurosurgical training programs globally. Moreover, the current coronavirus disease 2019 (COVID-19) pandemic may also show a negative impact on burnout levels in neurosurgery residents. This study aims to evaluate burnout, discrimination, and mistreatment in neurosurgical residents training in Latin America during the severe acute respiratory syndrome coronavirus 2 era. METHODS: A 33-item electronic survey was sent to neurosurgery residents from Latin America from May 10 to 25, 2021. Statistical analysis was performed using SPSS version 25. RESULTS: A total of 111 neurosurgery residents responded to the survey. Mean age was 29.39 ± 2.37 years; 22.5% were female and 36% were training in Mexico. Residents who reported experiencing discrimination for testing positive to COVID-19 had the highest levels of depersonalization (66.7%; P = 0.043) and emotional exhaustion (75%; P = 0.023). Female respondents reported higher rates of gender discrimination (80% vs. 1.2%; P = 0.001), abuse (84% vs. 58.1%; P < 0.005), and sexual harassment (24% vs. 0%; P < 0.001) than did male respondents. Residents training in Mexico reported lower rates of emotional or verbal abuse (59.2% vs. 32.5%; P = 0.007) and bullying (P < 0.005) than did those in other countries in Latin America. Older age was a protective factor for high depersonalization scores (odds ratio [OR], 0.133; 95% confidence interval [CI], 0.035-0.500). Experiencing discrimination represented a risk factor for presenting high emotional exhaustion scores (OR, 3.019; 95% CI, 1.057-8.629). High levels of depersonalization were associated with a 7-fold increased risk of suicidal ideation (OR, 7.869; 95% CI, 1.266-48.88). CONCLUSIONS: The COVID-19 pandemic has been a significant burden on several aspects of health care workers' lives. Our results provide a broad overview of its impact on burnout, discrimination, and mistreatment as experienced by neurosurgery residents training in Latin America, laying the groundwork for future studies and potential interventions.


Asunto(s)
Agotamiento Profesional , COVID-19 , Internado y Residencia , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , COVID-19/epidemiología , Femenino , Humanos , América Latina/epidemiología , Masculino , Pandemias , Encuestas y Cuestionarios
19.
Theor Appl Genet ; 123(5): 755-78, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21667037

RESUMEN

Breeding for fruit quality traits in strawberry (Fragaria × ananassa, 2n = 8x = 56) is complex due to the polygenic nature of these traits and the octoploid constitution of this species. In order to improve the efficiency of genotype selection, the identification of quantitative trait loci (QTL) and associated molecular markers will constitute a valuable tool for breeding programs. However, the implementation of these markers in breeding programs depends upon the complexity and stability of QTLs across different environments. In this work, the genetic control of 17 agronomical and fruit quality traits was investigated in strawberry using a F(1) population derived from an intraspecific cross between two contrasting selection lines, '232' and '1392'. QTL analyses were performed over three successive years based on the separate parental linkage maps and a pseudo-testcross strategy. The integrated strawberry genetic map consists of 338 molecular markers covering 37 linkage groups, thus exceeding the 28 chromosomes. 33 QTLs were identified for 14 of the 17 studied traits and approximately 37% of them were stable over time. For each trait, 1-5 QTLs were identified with individual effects ranging between 9.2 and 30.5% of the phenotypic variation, indicating that all analysed traits are complex and quantitatively inherited. Many QTLs controlling correlated traits were co-located in homoeology group V, indicating linkage or pleiotropic effects of loci. Candidate genes for several QTLs controlling yield, anthocyanins, firmness and L-ascorbic acid are proposed based on both their co-localization and predicted function. We also report conserved QTLs among strawberry and other Rosaceae based on their syntenic location.


Asunto(s)
Fragaria/genética , Frutas/genética , Sitios de Carácter Cuantitativo , Antocianinas/genética , Antocianinas/metabolismo , Mapeo Cromosómico , Cromosomas de las Plantas , Fragaria/crecimiento & desarrollo , Fragaria/metabolismo , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Ligamiento Genético , Marcadores Genéticos , Fenotipo , Polimorfismo Genético , Poliploidía
20.
J Am Anim Hosp Assoc ; 47(3): 170-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21498593

RESUMEN

Hemangiosarcoma (HSA) is an aggressive disease that is fairly common in the dog. The authors evaluated a doxorubicin, dacarbazine, and vincristine (DAV) combination protocol in dogs with nonresectable stage II and stage III HSA. Twenty-four dogs were enrolled in this prospective, phase 2 study. Doxorubicin and dacarbazine were administered on day 1 while vincristine was administered on days 8 and 15. The protocol was repeated every 21 days for a maximum of six cycles or until disease progression. Toxicity and efficacy were assessed by clinical and laboratory evaluation and by questionnaires completed by the owners. Of the 24 included dogs, 19 were evaluable for response. The response rate (including five complete responses and four partial responses) was 47.4%. Median time to tumor progression was 101 days and median overall survival was 125 days. Significant toxicities were noted, including 41 high-grade hematologic and 12 high-grade gastrointestinal toxic events. Five dogs discontinued treatment due to chemotherapy-related toxicities, but no treatment-related deaths occurred. Multivariate analysis identified patient age (relative risk [RR], 2.3, P=0.049) to be negatively associated with time to progression whereas dacarbazine dose reductions (RR, 0.06, P=0.031) were positively associated with time to progression. Dacarbazine dose reduction was the sole factor positively associated with overall survival (RR, 0.28, P=0.015). In conclusion, the DAV combination appears to offer clinical responses and may prolong survival in dogs with advanced-stage HSA.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Hemangiosarcoma/veterinaria , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioterapia Adyuvante/veterinaria , Dacarbazina/administración & dosificación , Dacarbazina/efectos adversos , Progresión de la Enfermedad , Perros , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Femenino , Hemangiosarcoma/tratamiento farmacológico , Masculino , Metástasis de la Neoplasia , Estadificación de Neoplasias/veterinaria , Análisis de Supervivencia , Resultado del Tratamiento , Vincristina/administración & dosificación , Vincristina/efectos adversos
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