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1.
Int J Surg Case Rep ; 119: 109715, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38704971

RESUMEN

INTRODUCTION AND IMPORTANCE: Buschke-Löwenstein tumor (BLT) is a rare perianal lesion caused by low-risk mucosal HPV 6 or 11 but less frequently associated with high-risk HPV types. It is a large, exophytic, verrucous lesion of the anogenital region. BLT presents as a benign tumor but exhibits malignant clinical behavior and has a high rate of local recurrence and malignant transformation. The optimal treatment approach for BLT is still debated due to the lack of consensus. Various therapeutic modalities have been proposed, including topical agents, surgical excision, immunotherapy, chemo-radiotherapy, and electrocoagulation. CASE PRESENTATION: This case report presents a heterosexual, immunocompetent patient with anal pain, pruritus, and spontaneous bleeding. The physical examination revealed an exophytic, pedunculated verrucous lesion, which appeared to be a typical fibroepithelial lesion. CLINICAL DISCUSSION: The patient underwent wide excision, followed by a re-excision due to a surgical margin issue. The tumor exhibited malignant transformation into a well-differentiated SCC. However, due to the tumor's stage, size, location, histological type, and the extended time interval between the two surgeries, postoperative radiotherapy was not performed. Follow-up examinations over 12 months revealed no evidence of recurrence in either the patient's clinical evaluation or pelvic MRI. CONCLUSIONS: Although comprehensive research is lacking, wide local excision is considered the preferred first-line treatment for early-stage cases without evidence of local invasion. Furthermore, HPV immunization can prevent the development of Buschke-Löwenstein tumor, and early administration of the HPV vaccine is recommended to avoid acquiring HPV infection.

2.
Front Physiol ; 13: 1037230, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36439266

RESUMEN

Vascular calcification (VC) is associated with a number of cardiovascular diseases, as well as chronic kidney disease. The role of smooth muscle cells (SMC) has already been widely explored in VC, as has the role of intracellular Ca2+ in regulating SMC function. Increased intracellular calcium concentration ([Ca2+]i) in vascular SMC has been proposed to stimulate VC. However, the contribution of the non-selective Piezo1 mechanosensitive cation channels to the elevation of [Ca2+]i, and consequently to the process of VC has never been examined. In this work the essential contribution of Piezo1 channels to arterial medial calcification is demonstrated. The presence of Piezo1 was proved on human aortic smooth muscle samples using immunohistochemistry. Quantitative PCR and Western blot analysis confirmed the expression of the channel on the human aortic smooth muscle cell line (HAoSMC). Functional measurements were done on HAoSMC under control and calcifying condition. Calcification was induced by supplementing the growth medium with inorganic phosphate (1.5 mmol/L, pH 7.4) and calcium (CaCl2, 0.6 mmol/L) for 7 days. Measurement of [Ca2+]i using fluorescent Fura-2 dye upon stimulation of Piezo1 channels (either by hypoosmolarity, or Yoda1) demonstrated significantly higher calcium transients in calcified as compared to control HAoSMCs. The expression of mechanosensitive Piezo1 channel is augmented in calcified arterial SMCs leading to a higher calcium influx upon stimulation. Activation of the channel by Yoda1 (10 µmol/L) enhanced calcification of HAoSMCs, while Dooku1, which antagonizes the effect of Yoda1, reduced this amplification. Application of Dooku1 alone inhibited the calcification. Knockdown of Piezo1 by siRNA suppressed the calcification evoked by Yoda1 under calcifying conditions. Our results demonstrate the pivotal role of Piezo1 channels in arterial medial calcification.

3.
Elife ; 112022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35929607

RESUMEN

Today septins are considered as the fourth component of the cytoskeleton, with the Septin7 isoform playing a critical role in the formation of higher-order structures. While its importance has already been confirmed in several intracellular processes of different organs, very little is known about its role in skeletal muscle. Here, using Septin7 conditional knockdown (KD) mouse model, the C2C12 cell line, and enzymatically isolated adult muscle fibers, the organization and localization of septin filaments are revealed, and an ontogenesis-dependent expression of Septin7 is demonstrated. KD mice displayed a characteristic hunchback phenotype with skeletal deformities, reduction in in vivo and in vitro force generation, and disorganized mitochondrial networks. Furthermore, knockout of Septin7 in C2C12 cells resulted in complete loss of cell division while KD cells provided evidence that Septin7 is essential for proper myotube differentiation. These and the transient increase in Septin7 expression following muscle injury suggest that it may be involved in muscle regeneration and development.


Asunto(s)
Fibras Musculares Esqueléticas , Músculo Esquelético , Animales , Diferenciación Celular , Ratones , Mitocondrias/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Septinas/genética , Septinas/metabolismo
4.
J Muscle Res Cell Motil ; 42(2): 251-265, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-31955380

RESUMEN

Appropriate organization of cytoskeletal components are required for normal distribution and intracellular localization of different ion channels and proteins involved in calcium homeostasis, signal transduction, and contractile function of striated muscle. Proteins of the contractile system are in direct or indirect connection with the extrasarcomeric cytoskeleton. A number of other molecules which have essential role in regulating stretch-, voltage-, and chemical signal transduction from the surface into the cytoplasm or other intracellular compartments are already well characterized. Sarcomere, the basic contractile unit, is comprised of a precisely organized system of thin (actin), and thick (myosin) filaments. Intermediate filaments connect the sarcomeres and other organelles (mitochondria and nucleus), and are responsible for the cellular integrity. Interacting proteins have a very diverse function in coupling of the intracellular assembly components and regulating the normal physiological function. Despite the more and more intense investigations of a new cytoskeletal protein family, the septins, only limited information is available regarding their expression and role in striated, especially in skeletal muscles. In this review we collected basic and specified knowledge regarding this protein group and emphasize the importance of this emerging field in skeletal muscle biology.


Asunto(s)
Músculo Estriado , Septinas , Citoesqueleto , Músculo Esquelético , Sarcómeros
5.
Antioxidants (Basel) ; 9(2)2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31979219

RESUMEN

BACKGROUND: Astaxanthin (AX) a marine carotenoid is a powerful natural antioxidant which protects against oxidative stress and improves muscle performance. Retinol and its derivatives were described to affect lipid and energy metabolism. Up to date, the effects of AX and retinol on excitation-contraction coupling (ECC) in skeletal muscle are poorly described. METHODS: 18 C57Bl6 mice were divided into two groups: Control and AX supplemented in rodent chow for 4 weeks (AstaReal A1010). In vivo and in vitro force and intracellular calcium homeostasis was studied. In some experiments acute treatment with retinol was employed. RESULTS: The voltage activation of calcium transients (V50) were investigated in single flexor digitorum brevis isolated fibers under patch clamp and no significant changes were found following AX supplementation. Retinol shifted V50 towards more positive values and decreased the peak F/F0 of the calcium transients. The amplitude of tetani in the extensor digitorum longus was significantly higher in AX than in control group. Lastly, the mitochondrial calcium uptake was found to be less prominent in AX. CONCLUSION: AX supplementation increases in vitro tetanic force without affecting ECC and exerts a protecting effect on the mitochondria. Retinol treatment has an inhibitory effect on ECC in skeletal muscle.

6.
Front Physiol ; 11: 601090, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33408641

RESUMEN

In mice a naturally occurring 12-bp deletion in the myostatin gene is considered responsible for the compact phenotype (MstnCmpt-dl1Abc, Cmpt) labeled by a tremendous increase in body weight along with signs of muscle weakness, easier fatigability, decreased Orai1 expression and store operated calcium entry (SOCE). Here, on the one hand, Cmpt fibers were reconstructed with venus-Orai1 but this failed to restore SOCE. On the other hand, the endogenous Orai1 was silenced in fibers from wild type C57Bl6 mice which resulted in ∼70% of Orai1 being silenced in whole muscle homogenates as confirmed by Western blot, accompanied by an inhibitory effect on the voltage dependence of SR calcium release that manifested in a slight shift toward more positive potential values. This maneuver completely hampered SOCE. Our observations are consistent with the idea that Orai1 channels are present in distinct pools responsible for either a rapid refilling of the SR terminal cisternae connected to each voltage-activated calcium transient, or a slow SOCE associated with an overall depletion of calcium in the SR lumen. Furthermore, when Cmpt cells were loaded with the mitochondrial membrane potential sensitive dye TMRE, fiber segments with depolarized mitochondria were identified covering on average 26.5 ± 1.5% of the fiber area. These defective areas were located around the neuromuscular junction and displayed significantly smaller calcium transients. The ultrastructural analysis of the Cmpt fibers revealed changes in the mitochondrial morphology. In addition, the mitochondrial calcium uptake during repetitive stimulation was higher in the Cmpt fibers. Our results favor the idea that reduced function and/or expression of SOCE partners (in this study Orai1) and mitochondrial defects could play an important role in muscle weakness and degeneration associated with certain pathologies, perhaps including loss of function of the neuromuscular junction and aging.

7.
Pathol Oncol Res ; 25(2): 801-805, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30715676

RESUMEN

We aimed to answer the question whether the decreased expression of protein kinase C (PKC) isoenzymes in the peripheral blood mononuclear cells (PBMC) of patients with systemic lupus erythematosus (SLE) is inherited or not. For this reason we examined the expression of PKC isoenzymes in a European white girl with acute SLE and in her healthy mother and father simultaneously in summer and winter during one year using western blotting and densitometry. We found that in the father the expression of PKC isoenzymes did not differ from that of eight healthy controls included women and men. However, in the "SLE-free" mother and in the patient arrived in July with acute symptoms of lupus, the expression of PKC isoenzymes showed a season dependent undulation in parallel. Namely, in summer the expression values were significantly lower, in winter they were significantly higher than those in the controls. Thus, the decreased expression of PKC isoenzymes in the PBMC of SLE patient is not a disease specific marker; it appears also in her lupus free mother. This phenomenon may be due to a season dependent female genetic background. However, the low PKC levels in summer can still decrease further the low production of IL-2 in T cells of lupus patients augmenting the existing AP-1 defects. This is the first report on the season and female dependent inherited changing of PKC expression in a European white patient with SLE and her mother. Further studies are needed to confirm these findings in other populations.


Asunto(s)
Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/enzimología , Proteína Quinasa C/sangre , Niño , Femenino , Humanos , Isoenzimas/sangre , Leucocitos Mononucleares/enzimología , Estaciones del Año , Adulto Joven
8.
Orv Hetil ; 155(38): 1524-9, 2014 Sep 21.
Artículo en Húngaro | MEDLINE | ID: mdl-25217769

RESUMEN

INTRODUCTION: Cortical auditory evoked potentials can provide objective information about the highest level of the auditory system. AIM: The purpose of the authors was to introduce a new tool, the "HEARLab" which can be routinely used in clinical practice for the measurement of the cortical auditory evoked potentials. In addition, they wanted to establish standards of the analyzed parameters in subjects with normal hearing. METHOD: 25 adults with normal hearing were tested with speech stimuli, and frequency specific examinations were performed utilizing pure tone stimuli. RESULTS: The findings regarding the latency and amplitude analyses of the evoked potentials confirm previously published results of this novel method. CONCLUSIONS: The HEARLAb can be a great help when performance of the conventional audiological examinations is complicated. The examination can be performed in uncooperative subjects even in the presence of hearing aids. The test is frequency specific and does not require anesthesia.


Asunto(s)
Estimulación Acústica/métodos , Corteza Cerebral/fisiología , Potenciales Evocados Auditivos , Sonido , Adulto , Femenino , Humanos , Masculino , Habla , Adulto Joven
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