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1.
Data Brief ; 56: 110796, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39263235

RESUMO

Monographic processing of Avar Period (6-8th century) glass beads. Approx. 200 glass beads have been selected from 13 archaeological sites in current day Hungary as the representatives of typical Avar glass beads. The beads were analyzed with electron microprobe analyzer attached with wavelength dispersive X-ray spectrometer and/or energy dispersive X-ray spectrometer peripheries for 12-15 elements complemented with archaeological and color description. These beads provide insights primarily into the trade and interactions of the Avar population in the Carpathian Basin with other peoples. Through their analysis, we can learn about the economic systems associated with glass production and the connections between different regions. Furthermore, Avar Age glass beads offer valuable information about craftsmanship and artistic expression. Their diverse shapes, colors, and patterns showcase the skill and creativity of the artisans who made them, as well as hint at the production technology used. The purpose of data collection is to identify the raw materials and coloring agents used in bead production, detect potential chronological changes, internationally explore the identified production technology in terms of space and time, and outline the Avars' trade network, and provide reference for future research. This is the first ever published database of Avar Age glass beads.

2.
Cancer Control ; 29: 10732748211068963, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35043700

RESUMO

The possible role of the naturally occurring deuterium in the regulation of cell division was first described in the 1990s. To investigate the mechanism of influence of deuterium (D) on cell growth, expression of 236 cancer-related and 536 kinase genes were tested in deuterium-depleted (40 and 80 ppm) and deuterium-enriched (300 ppm) media compared to natural D level (150 ppm). Among genes with expression changes exceeding 30% and copy numbers over 30 (124 and 135 genes, respectively) 97.3% of them was upregulated at 300 ppm D-concentration. In mice exposed to chemical carcinogen, one-year survival data showed that deuterium-depleted water (DDW) with 30 ppm D as drinking water prevented tumor development. One quarter of the treated male mice survived 344 days, the females 334 days, while one quarter of the control mice survived only 188 and 156 days, respectively. In our human retrospective study 204 previously treated cancer patients with disease in remission, who consumed DDW, were followed. Cumulative follow-up time was 1024 years, and average follow-up time per patient, 5 years (median: 3.6 years). One hundred and fifty-six patients out of 204 (77.9%) did not relapse during their 803 years cumulative follow-up time. Median survival time (MST) was not calculable due to the extremely low death rate (11 cancer-related deaths, 5.4% of the study population). Importantly, 8 out of 11 deaths occurred several years after stopping DDW consumption, confirming that regular consumption of DDW can prevent recurrence of cancer. These findings point to the likely mechanism in which consumption of DDW keeps D-concentration below natural levels, preventing the D/H ratio from increasing to the threshold required for cell division. This in turn can serve as a key to reduce the relapse rate of cancer patients and/or to reduce cancer incidence in healthy populations.


Assuntos
Deutério/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Recidiva Local de Neoplasia/genética , Neoplasias/genética , Água/administração & dosagem , Animais , Processos de Crescimento Celular/efeitos dos fármacos , Variações do Número de Cópias de DNA/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Recidiva Local de Neoplasia/prevenção & controle , Estudos Retrospectivos , Água/química
3.
Curr Issues Mol Biol ; 45(1): 66-77, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36661491

RESUMO

Research with deuterium-depleted water (DDW) in the last two decades proved that the deuterium/hydrogen ratio has a key role in cell cycle regulation and cellular metabolism. The present study aimed to investigate the possible effect of deuterium-depleted yolk (DDyolk) alone and in combination with DDW on cancer growth in two in vivo mouse models. To produce DDyolk, the drinking water of laying hens was replaced with DDW (25 ppm) for 6 weeks, resulting in a 60 ppm D level in dried egg yolk that was used as a deuterium-depleted food additive. In one model, 4T1, a cell line with a high metastatic capacity to the lung was inoculated in the mice's mammary pad. After three weeks of treatment with DDW and/or DDyolk, the tumor volume in the lungs was smaller in all treated groups vs. controls with natural D levels. Tumor growth and survival in mice transplanted with an MCF-7 breast cancer cell line showed that the anticancer effect of DDW was enhanced by food containing the deuterium-depleted yolk. The study confirmed the importance of the D/H ratio in consumed water and in metabolic water produced by the mitochondria while oxidizing nutrient molecules. This is in line with the concept that the initiation of cell growth requires the cells to generate a higher D/H ratio, but DDW, DDyolk, or the naturally low-D lipids in a ketogenic diet, have a significant effect on tumor growth by preventing the cells from raising the D/H ratio to the threshold.

4.
Data Brief ; 32: 106206, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32984454

RESUMO

The stable isotopic composition (δ18O, δ²H) and tritium activity of monthly aggregated precipitation samples were collected between April 2004 and December 2017 at six sites representing the first published precipitation isotope dataset from the Mecsek Hills (Hungary). The dataset includes 697 stable isotopic and 653 tritium activity concentration data of monthly precipitation samples collected across the Mecsek Hills. At the beginning of the monitoring period, the isotopic composition values suggest an insufficient protection against evaporation and this issue has occasionally reappeared later only in limited periods. These data are presented in brackets in the Supplementary Table and should be disregarded from further analysis until additional verification. This dataset provides isotope hydrological benchmark in comparison with other local and regional datasets of stable isotopes and tritium activities in surface water and groundwater not only in the Mecsek Hills but also in the surroundings. It can support water resource management, and paleoclimatological research. Isotope hydrological evaluation and further discussion on the seasonal trends in the precipitation isotopic characteristics are in progress and the tritium data were used in the derivation of a gridded database (1 × 1 km) of amount-weighted annual mean precipitation tritium activity for the Adriatic-Pannonian Region (AP3H_v1, [1]).

5.
Molecules ; 25(6)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197347

RESUMO

The effects of deuterium depletion on the human organism have been, except for the antitumor action, seldom investigated by now and the available data are scarce. In oncological patients who also suffered from diabetes and were treated with deuterium-depleted water (DDW), an improvement of glucose metabolism was observed, and rat studies also proved the efficacy of DDW to reduce blood sugar level. In the present work, 30 volunteers with pre- or manifest diabetes were enrolled to a clinical study. The patients received 1.5 L of water with reduced deuterium content (104 ppm instead of 145 ppm, equivalent 12 mmol/L in human) daily for 90 days. The effects on fasting glucose and insulin level, on peripheral glucose disposal, and other metabolic parameters were investigated. Fasting insulin and glucose decreased, and insulin reaction on glucose load improved, in 15 subjects, while in the other 15 the changes were opposite. Peripheral glucose disposal was improved in 11 of the subjects. In the majority of the subjects, substantial increase of serum high-density lipoprotein (HDL) cholesterol and significant decrease of serum Na+ concentration were also seen-the latter possibly due to activation of a Na+/H+ antiporter by the decreased intracellular deuterium level. The results support the possible beneficial role of DDW in disorders of glucose metabolism but leave questions open, requiring further studies.


Assuntos
Deutério/sangue , Jejum/sangue , Síndrome Metabólica/sangue , Adulto , Glicemia/metabolismo , Feminino , Humanos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Água/administração & dosagem
6.
Isotopes Environ Health Stud ; 52(1-2): 128-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25761056

RESUMO

As calculated from data archived in the IAEA-WMO Global Network of Isotopes in Precipitation programme, the amount-weighted local meteoric water line for the Pacific coast of central Panama is: δ(2)H = 7.63(±0.08) × Î´(18)O + 6.51(±0.49). Amount-weighted mean isotopic values were regressed against the sea surface temperature (SST) fields of the adjacent tropical oceans. A negative correlation of precipitation isotope composition with Caribbean SSTs is observed only for the early wet season (May-June), whilst the mid-summer dry period is characterized by positive correlation with eastern Pacific SSTs, similar to the late wet season (October-November). The negative response of May-June rainfall isotopic composition to Caribbean SSTs is explained by a SST-mediated change in stratiform rain fraction from organized convective systems proximal to the Inter Tropical Convergence Zone (ITCZ). The positive correlation for the rest of the wet season, when the organized convective zone of ITCZ and its attached stratiform belt are distant from the Pacific coast of Panama, is interpreted as simple evaporative temperature effect on isotopic fractionation.


Assuntos
Monitoramento Ambiental , Hidrogênio/análise , Oxigênio/análise , Chuva/química , Estações do Ano , Deutério/análise , Isótopos de Oxigênio/análise , Oceano Pacífico , Panamá
7.
Rapid Commun Mass Spectrom ; 21(18): 3006-14, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17705258

RESUMO

In stable isotope ratio mass spectrometry (IRMS), the stable isotopic composition of samples is measured relative to the isotopic composition of a working gas. This measured isotopic composition must be converted and reported on the respective international stable isotope reference scale for the accurate interlaboratory comparison of results. This data conversion procedure, commonly called normalization, is the first set of calculations done by the users. In this paper, we present a discussion and mathematical formulation of several existing routinely used normalization procedures. These conversion procedures include: single-point anchoring (versus working gas and certified reference standard), modified single-point normalization, linear shift between the measured and the true isotopic composition of two certified reference standards, two-point and multi-point linear normalization methods. Mathematically, the modified single-point, two-point, and multi-point normalization methods are essentially the same. By utilizing laboratory analytical data, the accuracy of the various normalization methods (given by the difference between the true and the normalized isotopic composition) has been compared. Our computations suggest that single-point anchoring produces normalization errors that exceed the maximum total uncertainties (e.g. 0.1 per thousand for delta(13)C) often reported in the literature, and, therefore, that it must not be used for routinely anchoring stable isotope measurement results to the appropriate international scales. However, any normalization method using two or more certified reference standards produces a smaller normalization error provided that the isotopic composition of the standards brackets the isotopic composition of unknown samples.


Assuntos
Algoritmos , Isótopos/química , Isótopos/normas , Espectrometria de Massas/métodos , Espectrometria de Massas/normas , Modelos Químicos , Simulação por Computador , Internacionalidade , Valores de Referência
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