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1.
PeerJ ; 11: e16277, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025719

RESUMO

The Messinian Salinity Crisis is considered as one of the most influential Cenozoic events that impacted negatively on the benthic fauna of the Mediterranean area. Changing environmental conditions, including a sharp reduction of water exchange between the Mediterranean Sea and the Atlantic Ocean, altered the geographical ranges of many organisms, including sponges (Porifera). Here, we report a unique assemblage of isolated sponge spicules from the upper Miocene of southwestern Spain. The newly recognized sponge fauna was inhabiting the Guadalquivir Basin-the corridor between the Mediterranean and the Atlantic Ocean at that time. It represents a taxonomically rich sponge community that consisted of members of "soft" and "lithistid" demosponges and hexactinellids. Demosponges are represented by at least thirty-four taxa, while hexactinellids are significantly rarer; only six taxa have been identified. From among eighteen taxa recognized to the species level, at least eight seem to be inhabiting this area to these days; six are recorded from adjacent areas, such as the Western Mediterranean, South European Atlantic Shelf, and the Azores, and three are present in the Red Sea and/or the Northern Atlantic. Intriguingly, some taxa seem to have their closest relatives in distant areas, such as the Indo-Pacific and Japanese waters which suggests that the range of some once widely-distributed populations shrunk after the isolation of the Mediterranean and the Messinian Salinity Crisis, surviving to the present day only in refugia.


Assuntos
Salinidade , Mar Mediterrâneo , Geografia , Espanha , Oceano Atlântico
2.
J Morphol ; 283(12): 1517-1545, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36208470

RESUMO

Sponges (Porifera) are a diverse and globally distributed clade of benthic organisms, with an evolutionary history reaching at least the Ediacaran-Cambrian (541 Ma) boundary interval. Throughout their research history, sponges have been subjects of intense studies in many fields, including paleontology, evolutionary biology, and even bioengineering and pharmacology. The skeletons of sponges are mostly characterized by the presence of mineral elements termed spicules, which structurally support the sponge bodies, though they also minimize the metabolic cost of water exchange and deter predators. The description of the spicules' shape and the skeleton organization represents the fundamental basis of sponge taxonomy and systematics. Here, we provide an illustrated catalogue of sponge spicules, which is based on previous works on sponge spicules, for example, and gathers and updates all terms that are currently used in sponge descriptions. Each spicule type is further illustrated through high quality scanning electron microscope micrographs. It is expected to be a valuable source that will facilitate spicule identification and, in certain cases, also enable sponge classification.


Assuntos
Paleontologia , Poríferos , Animais , Evolução Biológica , Esqueleto , Minerais
3.
PeerJ ; 10: e12842, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186460

RESUMO

Most previous publications on Devonian crinoids from the Holy Cross Mountains in Poland have concentrated on crinoid columns, and until now, little has been published about crinoid cups and calyxes. Herein, five crinoid taxa are described from an abundant occurrence of aboral cups and partial crowns from the Bukowa Góra Member (Emsian) in the Holy Cross Mountains of southern Poland. The following taxa are described: Bactrocrinites sp., Codiacrinus sevastopuloi sp. nov., Halocrinites geminatus (Bohatý, 2005), Halocrinites schlotheimii Steininger, 1831, and a single brachial plate from a flexible crinoid placed in Flexibilia incertae sedis. Simple discoid holdfasts are also present encrusted to cylindrical stromatoporoids. These taxa are the first crinoids described from the remains of partial crowns from Emsian strata of Poland.


Assuntos
Equinodermos , Poríferos , Animais , Polônia , Fósseis , Placas Ósseas
4.
Front Zool ; 18(1): 58, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749755

RESUMO

BACKGROUND: A basal spicule of the hexactinellid sponge Monorhaphis chuni may reach up to 3 m in length and 10 mm in diameter, an extreme case of large spicule size. Generally, sponge spicules are of scales from micrometers to centimeters. Due to its large size many researchers have described its structure and properties and have proposed it as a model of hexactinellid spicule development. Thorough examination of new material of this basal spicule has revealed numerous inconsistencies between our observations and earlier descriptions. In this work, we present the results of detailed examinations with transmitted light and epifluorescence microscopy, SEM, solid state NMR analysis, FTIR and X-ray analysis and staining of Monorhaphis chuni basal spicules of different sizes, collected from a number of deep sea locations, to better understand its structure and function. RESULTS: Three morphologically/structurally different silica layers i.e. plain glassy layer (PG), tuberculate layer (TL) and annular layer (AL), and an axial cylinder (AC) characterize adult spicules. Young, immature spicules display only plain glassy silica layers which dominate the spicule volume. All three layers i.e. PG, TL and AL can substitute for each other along the surface of the spicule, but equally they are superimposed in older parts of the spicules, with AL being the most external and occurring only in the lower part of the spicules and TL being intermediate between AL and PG. The TL, which is composed of several thinner layers, is formed by a progressive folding of its surface but its microstructure is the same as in the PG layer (glassy silica). The AL differs significantly from the PG and TL in being granular and porous in structure. The TL was found to display positive structures (tubercles), not depressions, as earlier suggested. The apparent perforated and non-perforated bands of the AL are an optical artefact. The new layer type that we called the Ripple Mark Layer (RML) was noted, as well as narrow spikes on the AL ridges, both structures not reported earlier. The interface of the TL and AL, where tubercles fit into depressions of the lower surface of the AL, represent tenon and mortise or dovetail joints, making the spicules more stiff/strong and thus less prone to breaking in the lower part. Early stages of the spicule growth are bidirectional, later growth is unidirectional toward the spicule apex. Growth in thickness proceeds by adding new layers. The spicules are composed of well condensed silica, but the outermost AL is characterized by slightly more condensed silica with less water than the rest. Organics permeating the silica are homogeneous and proteinaceous. The external organic net (most probably collagen) enveloping the basal spicule is a structural element that bounds the sponge body together with the spicule, rather than controlling tubercle formation. Growth of various layers may proceed simultaneously in different locations along the spicule and it is sclerosyncytium that controls formation of silica layers. The growth in spicule length is controlled by extension of the top of the axial filament that is not enclosed by silica and is not involved in further silica deposition. No structures that can be related to sclerocytes (as known in Demospongiae) in Monorhaphis were discovered during this study. CONCLUSIONS: Our studies resulted in a new insight into the structure and growth of the basal Monorhaphis spicules that contradicts earlier results, and permitted us to propose a new model of this spicule's formation. Due to its unique structure, associated with its function, the basal spicule of Monorhaphis chuni cannot serve as a general model of growth for all hexactinellid spicules.

5.
Radiol Oncol ; 55(2): 212-220, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33600676

RESUMO

BACKGROUND: Patients with left breast cancer who undergo radiotherapy have a non-negligible risk of developing radiation-induced cardiovascular disease (CVD). Cardioprotection can be achieved through better treatment planning protocols and through respiratory gating techniques, including deep inspiration breath hold (DIBH). Several dosimetric studies have shown that DIBH reduces the cardiac dose, but clinical data confirming this effect is limited. The aim of the study was to compare the mean heart dose (MHD) in patients with left breast cancer who underwent radiotherapy at our institution as we transitioned from non-gated free-breathing (FB) radiotherapy to gated radiotherapy (FB-GRT), and finally to DIBH. PATIENTS AND METHODS: Retrospective study involving 2022 breast cancer patients who underwent radiotherapy at West Pomeranian Oncology Center in Szczecin from January 1, 2014 through December 31, 2017. We compared the MHD in these patients according to year of treatment and technique. RESULTS: Overall, the MHD for patients with left breast cancer in our cohort was 3.37 Gy. MHD values in the patients treated with DIBH were significantly lower than in patients treated with non-gated FB (2.1 vs. 3.48 Gy, p < 0.0001) and gated FB (3.28 Gy, p < 0.0001). The lowest MHD values over the four-year period were observed in 2017, when nearly 85% of left breast cancer patients were treated with DIBH. The proportion of patients exposed to high (> 4 Gy) MHD values decreased every year, from 40% in 2014 to 7.9% in 2017, while the percentage of patients receiving DIBH increased. CONCLUSIONS: Compared to free-breathing techniques (both gated and non-gated), DIBH reduces the mean radiation dose to the heart in patients with left breast cancer. These findings support the use of DIBH in patients with left breast cancer treated with radiotherapy.


Assuntos
Suspensão da Respiração , Coração/efeitos da radiação , Inalação , Órgãos em Risco/efeitos da radiação , Lesões por Radiação/prevenção & controle , Neoplasias Unilaterais da Mama/radioterapia , Intervalos de Confiança , Feminino , Humanos , Doses de Radiação , Radioterapia de Intensidade Modulada/tendências , Estudos Retrospectivos , Fatores de Tempo
6.
Radiat Environ Biophys ; 60(2): 377-381, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33483777

RESUMO

In recent years, a method for designing radiotherapy boluses using 3D printing technology has been established in the West Pomeranian Oncology Centre in Szczecin, Poland. The aim of the present study was to investigate whether the ionising radiation used in radiotherapy affects the physical properties of the printing material. Particularly, the purpose of this study was to determine the effect of a 60 Gy X-ray radiation dose on the hardness and dimensions of 3D-printed boluses. Four cuboids were printed on a Zortrax M200 printer with acrylonitrile-butadiene-styrene (ABS) polymer. All printed samples were exposed to 60 Gy of X-ray radiation delivered by a medical accelerator. After irradiation, changes in the hardness (using Vickers test) and dimensions of the prints were measured. The therapeutic X-ray dose had a minimal effect on the dimensions of the printed samples, resulting in a maximum contraction of only 0.4%. Changes of the hardness were not statistically significant. In conclusion, regarding the radiotherapy planning process, the application of this therapeutic X-ray dose does not significantly influence the hardness and dimensions of ABS-printed boluses.


Assuntos
Resinas Acrílicas , Butadienos , Poliestirenos , Impressão Tridimensional , Planejamento da Radioterapia Assistida por Computador , Dureza , Raios X
7.
Rep Pract Oncol Radiother ; 26(6): 899-905, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34992861

RESUMO

BACKGROUND: The present paper reports on analysis of 184 patients who were diagnosed with endometrial cancer. The main objective of this study was to address parameter Vrec(30Gy) which determines a volume of the rectum irradiated with a dose of 30 Gy during radiotherapy. MATERIALS AND METHODS: All patients were irradiated with an IMRT technique on linear accelerators. The planning target volume (PTV) contour was determined by a radiation oncologist. The clinical target volume (CTV) was drawn on CT images obtained in a prone position. For statistical analysis, appropriate tests (e.g. the Shapiro-Wilk, Wilcoxon) were used. RESULTS AND DISCUSSION: The performed analysis showed that the recommended condition for Vrec(30Gy) is met only in 3% of patients and the observed median value exceeds 90%. The obtained results were compared with the studies in which the Vrec(30Gy) values were related to various radiotherapy techniques. CONCLUSIONS: The analysis showed that the condition for Vrec(30Gy) is satisfied in the case of only 3% of patients. Due to the difficulty with meeting the condition, it should be reconsidered based on real results.

8.
Pulse (Basel) ; 9(3-4): 83-88, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35083174

RESUMO

INTRODUCTION: Radiotherapy plays a prominent role in the multidisciplinary treatment of cancers. Despite new irradiation techniques, radiation-induced cardiotoxicity remains a leading cause of morbidity and mortality. Therefore, prognostic indicators of radiotherapy toxicity are essential. This study aimed to investigate the influence of applied radiotherapy on the pulse wave recording and thereby on cardiovascular health, as well as to assess whether high signal resolution (HSR) pulse oximetry could be used as a prognostic indicator of radiotherapy toxicity. METHODS: A total of 19 patients treated with radiotherapy to the lung or left breast were analyzed. Pulse oximetry was performed on all eligible patients (before and after the administration of a radiation dose) using the PULS-HSR program, which increases the resolution of the pulse wave recording. RESULTS: Among the analyzed variables, we found the total dose administered to the target, as well as the treatment duration, significantly positively correlated with the change in ventricle/aorta volume ratio. The ventricle/aorta volume ratio parameter is the ratio between the area under the HSR pulse wave generated by the contraction of the left ventricle until the aortic valve closes and the area of the HSR pulse wave responsible for expansion and contraction of the aorta. CONCLUSION: The pilot study indicates HSR pulse oximetry, especially the ventricle/aorta volume ratio parameter, as a potential prognostic indicator of toxicity from radiation for breast and lung cancers.

9.
PeerJ ; 8: e10601, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33384908

RESUMO

Most sponges produce skeletons formed by spicules, structural elements that develop in a wide variety of sizes and tridimensional shapes. The morphologies of spicules are often unique to clade- or even species-level taxa which makes them particularly useful in taxonomic assignments. When dead sponge bodies disintegrate, spicules become incorporated into sediments and sometimes accumulate into enormous agglomerations called spicule mats or beds, or fossilize to form special type of rocks called the spiculites. The record of fossil and subfossil sponge spicules is extraordinarily rich and often serves as a basis for far-reaching reconstructions of sponge communities, though spicules are also bearers of significant ecological and environmental information. Specific requirements and preferences of sponges can be used to interpret the environment in which they lived, and reconstruct oscillations in water depths, pH, temperatures, and other parameters, providing snapshots of past climate conditions. In turn, the silicon isotope compositions in spicules (δ30Si) are being increasingly often used to estimate the level of silicic acid in the marine settings throughout the geological history, which enables to reconstruct the past silica cycle and ocean circulation. This contribution provides a review of the use of sponge spicules in reconstructions of sponge communities, their ecology, and environments, and aims to detect the pertinent gaps in their utilization. Even though spicules are well known for their significance as bearers of taxonomic, ecological, and environmental data, their potential remains to be fully exploited.

10.
J Appl Clin Med Phys ; 18(1): 76-81, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28291910

RESUMO

This work describes the use of 3D printing technology to create individualized boluses for patients treated with electron beam therapy for skin lesions of the eye canthi. It aimed to demonstrate the effectiveness of 3D-printed over manually fabricated paraffin boluses. The study involved 11 patients for whom the construction of individual boluses were required. CT scans of the fabricated 3D-printed boluses and paraffin boluses were acquired and superimposed onto patient CT scans to compare their fitting, bolus homogeneity, and underlying dose distribution. To quantify the level of matching, multiple metrics were utilized. Matching Level Index (ML) values ranged from 0 to 100%, where 100% indicated a perfect fit between the reference bolus (planned in treatment planning system) and 3D-printed and paraffin bolus. The average ML (± 1 SD) of the 3D-printed boluses was 95.1 ± 2.1%, compared to 46.0 ± 10.1% for the manually fabricated paraffin bolus. Correspondingly, mean doses were closer to the prescribed doses, and dose spreads were less for the dose distributions from the 3D-printed boluses, as compared to those for the manually fabricated paraffin boluses. It was concluded that 3D-printing technology is a viable method for fabricating boluses for small eye lesions and provides boluses superior to our boluses manually fabricated from paraffin sheets.


Assuntos
Carcinoma Basocelular/radioterapia , Carcinoma de Células Escamosas/radioterapia , Elétrons/uso terapêutico , Oftalmopatias/radioterapia , Impressão Tridimensional/estatística & dados numéricos , Dermatopatias/radioterapia , Humanos , Impressão Tridimensional/instrumentação , Garantia da Qualidade dos Cuidados de Saúde , Dosagem Radioterapêutica
11.
Heart Surg Forum ; 19(4): E185-6, 2016 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-27585198

RESUMO

Three-dimensional (3D) printing involves preparing 3D objects from a digital model. These models can be used to plan and practice surgery. We used 3D printing to plan for a rare complicated surgery involving the removal of a renal tumor and neoplastic mass, which reached the heart atrium. A printed kidney model was an essential element of communication for physicians with different specializations.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Neoplasias Cardíacas/secundário , Comunicação Interdisciplinar , Neoplasias Renais/diagnóstico , Impressão Tridimensional , Ecocardiografia Transesofagiana , Átrios do Coração , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirurgia , Humanos , Imageamento Tridimensional , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Técnicas de Planejamento , Tomografia Computadorizada por Raios X
12.
Rep Pract Oncol Radiother ; 21(3): 225-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27601955

RESUMO

BACKGROUND: Novel techniques in oncology provide new treatment opportunities but also introduce different patterns of side effects. Intraoperative radiotherapy (IORT) allows a shortened overall treatment time for early breast cancer either combined with whole breast radiotherapy (WBRT), or alone. Although the early side effects of IORT are well known, data on clinically important late side effects, which require medical intervention, are scarce. AIM: In this study, we analyze risk factors for seroma evacuation more than 6 months after IORT. MATERIALS AND METHODS: We evaluated 120 patients with a mean follow-up of 27.8 months (range: 7-52 months). Fifty-one patients received IORT only and 69 were additionally treated with WBRT. RESULTS: Seroma evacuation was performed 6-38 months after IORT. Two (3.9%) events were observed in the IORT group and 14 (20%) in the IORT + WBRT group. Univariate (Kaplan-Meier) analysis showed that addition of WBRT to IORT increased the risk of seroma evacuation [hazard ratio = 5.5, 95% confidence interval: 2.0-14.7, P = 0.011]. In a multivariate analysis (Cox proportional hazards regression), WBRT and axillary lymph node dissection were significant risk factors for seroma evacuation (model P value = 0.0025). CONCLUSIONS: WBRT applied after IORT is associated with increased risk of seroma evacuation, which might be considered as a late side effect.

13.
Zootaxa ; 3917: 1-65, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25662358

RESUMO

An abundant and diversified assemblage of siliceous loose sponge spicules has been identified in the Late Eocene deposits cropping out along the southern coasts of Australia. Based on the comparison of the obtained spicules with those of living sponges, representatives of at least 43 species within 33 genera, 26 families, and 9 orders of "soft" Demospongiae and Homoscleromorpha have been identified in the assemblage. Within the studied sediments, the spicules representing demosponge orders Poecilosclerida, Hadromerida, and Astrophorida were the most diverse. The rest of the five demosponge orders (Halichondrida, Agelasida, Haplosclerida, Spirophorida, and Chondrosida) are represented by single families. Also, a single family Plakinidae within the class Homoscleromorpha that includes two genera was present. The diversity of spicules is similar in all studied samples and areas, even distant geographically, and there are only minor differences between the sections. That indicates a homogenous character of this rich siliceous sponge assemblage. Most of the studied sponge spicules have Recent equivalents among present-day siliceous spicules. However, the fossil ones are bigger which is most likely due to different environmental conditions. Among the recognized sponge species, at least eleven (Agelas cf. axifera, Agelas cf. wiedenmayeri, Penares sclerobesa, Histodermella australis, Trikentrion flabelliforme, Cliona cf. mucronata, Tethya cf. omanensis, Terpios sp., Placinolopha cf. sarai, Dotona pulchella, and Sigmosceptrella quadrilobata) are noted for the first time in the fossil record.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Austrália , Tamanho Corporal , Ecossistema , Fósseis/anatomia & histologia , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
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