106 research outputs found
MicroRNA-related sequence variations in human cancers
MicroRNAs are emerging as a most promising field in basic and translational research, explaining the pathogenesis of numerous human diseases and providing excellent tools for their management. This review considers the effects of microRNA sequence variations and their implication in pathogenesis and predisposition to human cancers. Although the role of microRNAs still remains to be elucidated, functional, and populational studies indicate that microRNA variants are important factors underlying the process of carcinogenesis. Further understanding of the cellular and molecular basis of microRNA action will lead to the identification of their new target genes and microRNA-regulated pathways. As a consequence, novel models of cancer pathogenesis can be proposed, and serve as a basis for elucidation of new prognostic and diagnostic tools for human cancers
Impact of systemic hypoxemia on cancer aggressiveness and circulating vascular endothelial growth factors A and C in gastroesophaeal cancer patients with chronic respiratory insufficiency
Aim: Due to the common etiologic factor, a considerable number of esophagogastric cancer patients suffer from respiratory insufficiency in course of chronic obstructive pulmonary disease, primary to cancer. Systemic hypoxemia may account for poor oxygenation of tumor tissue-a main driving force of tumor neoangiogenesis. We hypothesized that in cancer patients with respiratory insufficiency, systemic hypoxemia may be related to enhanced aggressiveness of cancer on one side and to the elevation of angiogenic factors on the other. Methods: The levels of vascular endothelial growth factors A and C were determined with immunoenzymatic methods in patients diagnosed with esophagogastric cancer with or without co-existing respiratory insufficiency in course of chronic obstructive pulmonary disease and in healthy controls. Blood gasometry and hemoglobin levels of cancer patients were related to cancer histology and TNM status, and to circulating vascular endothelial growth factors A and C. Results: Patients with systemic hypoxemia had higher incidence rates of locally advanced tumors. Partial oxygen pressure and blood oxygen saturation were significantly lowered in patients with T4 cancers as compared to less advanced onces. Circulating vascular endothelial growth factor A, but not C, was more elevated in esophagogastric cancer patients with co-existing respiratory insufficiency, as compared to those without respiratory insufficiency. Vascular endothelial growth factor A was also strongly related to the extension of primary tumor. Conclusion: Our results show that systemic hypoxemia in esophagogastric cancer patients is associated with the extension of primary tumor and that this effect might be mediated by the up-regulation of circulating vascular endothelial growth factor A.Цель: в связи с общим этиологическим фактором заболевания , значительное количество больных гастроэзофагальным
раком страдает от респираторной недостаточности в процессе хронического обструктивного легочного заболевания, кото-
рое предшествует раку. Системная гип оксемия может влиять на пониженн ую оксигена цию опухолево й ткани — основной
источник опухолевого неоангиогенеза. Авторы предп оложили , что у больных онкологического п рофиля с респираторно й
недостаточностью системная гипоксемия может быть связана с повышенной агрессивностью опухолевого процесса, с
одной стороны, и повышенным уровнем ангиогенных факторов — с другой. Методы: сод ержание факторов роста эндо-
телия сосудов A и C ( VEGF ) опред еляли имму ноферментными мето дами у пациентов с гастроэзофагальным раком на фоне
респираторной недостаточности в процессе хронического обструктивного заболевания легких или в отсутствие такового,
а также у здоровых доноров. Анализировали д анные газометрии и сод ержания гемоглобина в зависимости от гистологии
новообразования, статуса TNM и уровня VEGF A и C. Результаты: у больных с системно й гипоксемие й частота появления
новообразований была выше. Парциальное давление кислоро да и насыщение крови кислоро д ом значительно снижено у
пациентов с категорией T4. Повышение сод ержания циркулирующего VEGF A, но не C, более выражено у больных с респи-
раторной недостаточностью, чем без нее. Содержание VEGF коррелировало с объемом первично й опухоли . Выводы: на
результаты показывают, что системная гипоксемия у пациентов с гастроэзофагальным раком связана с увеличением объема
первичной опухоли, и такой эффект может быть опосредован повышением содержания циркулирующего VEGF
Respiratory insufficiency related to copd accelerates systemic inflammation, under-nutrition, and angiogenesis in esophageal malignancies
A number of esophageal cancer patients suffer from respiratory insufficiency due to the coexistence of chronic obstructive pulmonary disease (COPD). Aim: To test the hypothesis that COPD-related systemic hypoxemia may result in accelerated inflammation, malnutrition, and angiogenesis in esophageal cancer patients. Methods: Serum levels of C-reactive protein (CRP), albumin, transferrin, interleukin-1, interleukin-6, interleukin-8, TNF- a, platelet-derived growth factor (PDGF-BB), and midkine and patient BMI and weight-loss rate were determined and compared with blood oxygenation status (pO2, SaO2) in 35 esophageal cancer patients and 42 controls. Results: The incidence of cachexia tended to be higher in patients with systemic hypoxemia (67% vs 40%, p = 0.169). Mean SaO2 level was also significantly decreased in cachectic patients (90.3 vs 93.3%, p = 0.026) and pO2 exhibited a similar trend (58.0 vs 63.4 mmHg, p = 0.120). Transferrin (234 vs 316 mg/dl, p = 0.005) and albumin (31.9 vs 37.1 mg/dl, p = 0.002) concentrations were reduced and CRP was elevated (129.9 vs 54.7 mg/l, p = 0.004) in hypoxemic patients and correlated with pO2 (r = 0.47, p = 0.016; r = 0.48, p = 0.012; r = –0.37, p = 0.064) and SaO2 (r = 0.52, p = 0.006; r = 0.53, p = 0.006; r = –0.40, p = 0.042). Interleukin-6 (9.97 vs 2.21 pg/ml, p = 0.005) and midkine (2101 vs 944 pg/ml, p < 0.001) were elevated and PDGF-BB was decreased (12.2 vs 17.3 pg x 10-6/PLT, p = 0.014) in hypoxemic compared with normoxemic patients. Interleukin-6 and midkine negatively correlated with pO2 (r = –0.44, p = 0.016; r = –0.42, p = 0.011) and SaO2 (r = –0.54, p = 0.003; r = –0.57, p < 0.0001) and PDGF-BB correlated positively (r = 0.53, p = 0.003; r = 0.44, p = 0.020). Interleukin-8 level was affected by pO2 (r = -0.55, p = 0.015) and SaO2 (r = –0.55, p = 0.018) only in hypoxemic patients. Conclusions: COPD-related systemic hypoxemia negatively affects the status of esophageal cancer patients by accelerating inflammation, under-nutrition, and angiogenesis.Многие больные раком пищевода страдают от респираторной недостаточности из-за развития хронического обструктивного
легочного заболевания (COPD). Цель: Проверить гипотезу о возможной связи системной гипоксемии, ассоциированной
с COPD, с усилением воспалительных процессов, истощением и ангиогенезом у больных раком пищевода.
Методы: у 35 больных раком пищевода и 42 здоровых доноров определяли уровень CRP, альбумина, трансферина,
интерлейкина-1, интерлейкина-6, интерлейкина-8, TNF-α, PDGF-BB и мидкина в сыворотке крови, показатели BMI и
потери веса больных, а также показатели уровня оксигенации крови (pO2
, SaO2
). Результаты: частота возникновения
кахексии была выше у больных с системной гипоксемией (67 против 40%, p = 0,169). Средний уровень SaO2
был также
значительно снижен у больных с кахексией (90,3 против 93,3%, p = 0,026), с той же тенденцией и для уровня pO2
(58,0
против 63,4 mmHg, p = 0,120). Концентрации трансферина (234 против 316 мг/дл, p = 0,005) и альбумина (31,9 против
37,1 мг/дл, p = 0,002) были снижены, CRP повышен (129,9 против 54,7 мг/л, p = 0,004) у гипоксемических пациентов,
что кореллировало с показателями pO2
(r = 0,47, p = 0,016; r = 0,48, p = 0,012; r = –0,37, p = 0,064) и SaO2
(r = 0,52,
p = 0,006; r = 0,53, p = 0,006; r = –0,40, p = 0,042). Уровень интерлейкина-6 (9,97 против 2,21 pg/ml, p = 0,005) и мидкина
(2101 против 944 pg/ml, p < 0,001) был также повышен, а уровень PDGF-BB понижен (12,2 против 17,3 pg × 10-6/PLT,
p = 0,014) у гипоксемических больных по сравнению с показателями при нормоксемии. Уровни интерлейкина-6 и мидкина
негативно кореллировали с показателями pO2
(r = –0,44, p = 0,016; r = –0,42, p = 0,011) и SaO2
(r = –0,54, p = 0,003;
r = –0,57, p < 0,0001) и позитивно — с PDGF-BB (r = 0,53, p = 0,003; r = 0,44, p = 0,020). На уровень интерлейкина-8
влияли pO2
(r = –0,55, p = 0,015) и SaO2
(r = –0,55, p = 0,018) только у больных с гипоксемией. Выводы: ассоциированная
с COPD системная гипоксемия негативно влияет на состояние больных раком пищевода за счет ускорения воспалительных
процессов, истощения и ангиогенез
Hypothalamic ERK Mediates the Anorectic and Thermogenic Sympathetic Effects of Leptin
OBJECTIVE—Leptin is an adipocyte hormone that plays a major role in energy balance. Leptin receptors in the hypothalamus are known to signal via distinct mechanisms, including signal transducer and activator of transcription-3 (STAT3) and phosphoinositol-3 kinase (PI 3-kinase). Here, we tested the hypothesis that extracellular signal–regulated kinase (ERK) is mediating leptin action in the hypothalamus
Seismic constraints from a Mars impact experiment using InSight and Perseverance
NASA’s InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission has operated a sophisticated suite of seismology and geophysics instruments on the surface of Mars since its arrival in 2018. On 18 February 2021, we attempted to detect the seismic and acoustic waves produced by the entry, descent and landing of the Perseverance rover using the sensors onboard the InSight lander. Similar observations have been made on Earth using data from both crewed1,2 and uncrewed3,4 spacecraft, and on the Moon during the Apollo era5, but never before on Mars or another planet. This was the only seismic event to occur on Mars since InSight began operations that had an a priori known and independently constrained timing and location. It therefore had the potential to be used as a calibration for other marsquakes recorded by InSight. Here we report that no signal from Perseverance’s entry, descent and landing is identifiable in the InSight data. Nonetheless, measurements made during the landing window enable us to place constraints on the distance–amplitude relationships used to predict the amplitude of seismic waves produced by planetary impacts and place in situ constraints on Martian impact seismic efficiency (the fraction of the impactor kinetic energy converted into seismic energy)
Disturbed Expression of Splicing Factors in Renal Cancer Affects Alternative Splicing of Apoptosis Regulators, Oncogenes, and Tumor Suppressors
BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cancer. One of the processes disturbed in this cancer type is alternative splicing, although phenomena underlying these disturbances remain unknown. Alternative splicing consists of selective removal of introns and joining of residual exons of the primary transcript, to produce mRNA molecules of different sequence. Splicing aberrations may lead to tumoral transformation due to synthesis of impaired splice variants with oncogenic potential. In this paper we hypothesized that disturbed alternative splicing in ccRCC may result from improper expression of splicing factors, mediators of splicing reactions. METHODOLOGY/PRINCIPAL FINDINGS: Using real-time PCR and Western-blot analysis we analyzed expression of seven splicing factors belonging to SR proteins family (SF2/ASF, SC35, SRp20, SRp75, SRp40, SRp55 and 9G8), and one non-SR factor, hnRNP A1 (heterogeneous nuclear ribonucleoprotein A1) in 38 pairs of tumor-control ccRCC samples. Moreover, we analyzed splicing patterns of five genes involved in carcinogenesis and partially regulated by analyzed splicing factors: RON, CEACAM1, Rac1, Caspase-9, and GLI1. CONCLUSIONS/SIGNIFICANCE: We found that the mRNA expression of splicing factors was disturbed in tumors when compared to paired controls, similarly as levels of SF2/ASF and hnRNP A1 proteins. The correlation coefficients between expression levels of specific splicing factors were increased in tumor samples. Moreover, alternative splicing of five analyzed genes was also disturbed in ccRCC samples and splicing pattern of two of them, Caspase-9 and CEACAM1 correlated with expression of SF2/ASF in tumors. We conclude that disturbed expression of splicing factors in ccRCC may possibly lead to impaired alternative splicing of genes regulating tumor growth and this way contribute to the process of carcinogenesis
Surface waxes as a plant defense barrier towards grain aphid
The electrical penetration graph (EPG) method was used to quantify the effect of surface waxes on probing
behaviour of the grain aphid Sitobion avenae F. (Hemiptera: Aphididae). The experiments showed that wax
removal significantly affected probing behaviour of S. avenae. Generally, the aphids feeding on the plants without
wax had a shortened non-probing (EPG-pattern np) and prolonged penetration of peripheral tissues – epidermis
and mesophyll (EPG-pattern C). The EPG tests also showed that the three tested extracts of surface
waxes from waxy plants RAH 122 were active as aphicides against the grain aphid
Changes in pigment content of triticale genotypes infested with grain aphid Sitobion avenae (Fabricius) (Homoptera: Aphididae)
COVID-19 patient in a dental office – literature review
ntroduction. The outbreak of the COVID-19 pandemic caused by the SARS-COV-2 virus affected the functioning of dental
care. Dentists performing procedures in the patient’s respiratory tract, creating an aerosol, constitute a group of high risk
of infection. Over the years, the universal way of cross-matching has changed.
Objective. The aim of the study is to review the current literature and present the impact of the pandemic on dental
practices, and the introduced new solutions to existing procedures to prevent infections among workers and patients.
State of knowledge. Dental office workers are exposed to a virus with a high potential for spreading among the population.
Most of the infected patients (80%) are asymptomatic, therefore each patient should be treated as a potential carrier of SARS-
COV-2. Practice rooms should be adapted by removing unnecessary items, such as newspapers and brochures. Providing
a higher level of personal protective equipment, minimum FFP, and covering the body surface create a physical barrier
against this pathogen. It is recommended to use manual intruments instead of mechanical ones which generate aerosol
during dental procedures. Non-contact channels of communication with the patient (teledentistry) eliminate the risk of
infection and should be used in the initial patient assessment and medical advice that does not require a personal visit.
Conclusions. In the face of the pandemic caused by the SARS-COV-2 virus, it is the duty of dentists to properly prepare
their offices, provide personal protective equipment to medical staff and patients, and adapt medical procedures to combat
the epidemic situation. Dentists should also use teledentistry, which, with certain limitations, allows them to help patients
without the risk of transmitting the virus
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