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1.
Nat Ecol Evol ; 8(3): 552-563, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38238436

RESUMO

The geographic expansion of Homo sapiens populations into southeastern Europe occurred by ∼47,000 years ago (∼47 ka), marked by Initial Upper Palaeolithic (IUP) technology. H. sapiens was present in western Siberia by ∼45 ka, and IUP industries indicate early entries by ∼50 ka in the Russian Altai and 46-45 ka in northern Mongolia. H. sapiens was in northeastern Asia by ∼40 ka, with a single IUP site in China dating to 43-41 ka. Here we describe an IUP assemblage from Shiyu in northern China, dating to ∼45 ka. Shiyu contains a stone tool assemblage produced by Levallois and Volumetric Blade Reduction methods, the long-distance transfer of obsidian from sources in China and the Russian Far East (800-1,000 km away), increased hunting skills denoted by the selective culling of adult equids and the recovery of tanged and hafted projectile points with evidence of impact fractures, and the presence of a worked bone tool and a shaped graphite disc. Shiyu exhibits a set of advanced cultural behaviours, and together with the recovery of a now-lost human cranial bone, the record supports an expansion of H. sapiens into eastern Asia by about 45 ka.


Assuntos
Fósseis , Crânio , Humanos , China , Europa (Continente) , Antropologia Cultural
2.
Heliyon ; 9(9): e19531, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809458

RESUMO

Cooking events can generate household air pollutants that deteriorate indoor air quality (IAQ), which poses a threat to human health and well-being. In this study, the emission characteristics and emission factors (EFs) of air pollutants of different meats (beef, lamb, chicken, pork, and fish) cooked by a novel oil-free process and common with-oil processes were investigated. Oil-free cooking tends to emit lower total volatile organic compound (TVOC) levels and fewer submicron smoke particles and can reduce the intake of fat and calories. However, TVOC emissions during oil-free cooking were significantly different, and the lamb EFs were nearly 8 times higher than those during with-oil cooking. The particle-bound polycyclic aromatic hydrocarbon (Æ©PPAH) and benzo(a)pyrene-equivalent (Æ©BaPeq) EFs during with-oil cooking ranged from 76.1 to 140.5 ng/g and 7.7-12.4 ng/g, respectively, while those during oil-free cooking ranged from 41.0 to 176.6 ng/g and 5.4-47.6 ng/g, respectively. The Æ©PPAH EFs of chicken, pork, and fish were lower during oil-free cooking than during cooking with oil. Furthermore, the Æ©BaPeq EFs of beef, chicken, pork, and fish were lower during oil-free cooking than during cooking with oil. Therefore, it is recommended to use the oil-free method to cook chicken, pork, and fish to reduce Æ©PPAH and Æ©BaPeq emissions, but not recommended to cook lamb due to the increase of Æ©BaPeq emissions. The with-oil uncovered cooking EFs of aldehydes ranged from 3.77 to 22.09 µg/g, and those of oil-free cooking ranged from 4.88 to 19.96 µg/g. The aldehyde EFs were lower during oil-free covered cooking than with-oil uncovered cooking for beef, chicken, and fish. This study provides a better realizing of new cooking approaches for the reduction of cooking-induced emission, but further research on the effects of food composition (moisture and fat) and characteristics is needed.

3.
Microorganisms ; 11(10)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37894032

RESUMO

Hemoprotozoa are microorganisms that parasitize the blood and possess intricate life cycles. Despite the complexity of their nature, little is known about the biology of hemoprotozoa in reptilian hosts. In this study, we conducted disease surveillance on blood samples collected from six black spiny-tailed iguanas (Ctenosaura similis) exhibiting clinical signs. We found two different types of hemoparasites in the blood films and further confirmed they belong to the genera Lakesterella and Hepatozoon through molecular methods. In the tissue section from a dead iguana infected only with Lakesterella sp., parasites were also found in melanomacrophages of the liver and kidney. Since Lakesterella sp. infection has not been reported in C. similis, we propose this hemococcidian as a new species, Lankesterella desseri n. sp. The Hepatozoon parasites discovered in this study were classified as Hepatozoon gamezi based on their morphological characteristics, particularly the notable deformation of all infected erythrocytes, and this classification was further corroborated through molecular biological and phylogenetic analyses. This is the first hemoprotozoa investigation in C. similis with pathological and molecular characterization of these pathogens. We suggest that more studies are needed to understand the epidemiology, transmission, and impact of these parasites on their hosts and ecosystems.

4.
Biochem Genet ; 61(3): 1185-1209, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36534333

RESUMO

Terpene synthases (TPSs) catalyze terpenoid synthesis and affect the intracellular isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) concentration. In this study, we mined the in silico genome-wide TPS genes of Hevea brasiliensis and identified 47 full-length TPS genes. They had DDXXD, DXDD, NSE/DTE, RR(X)8 W, EA(X)W, and other conserved motifs. The phylogenetic tree analysis revealed that the TPSs of H.brasiliensis (HbTPSs) were divided into five subfamilies, TPS-a, TPS-b, TPS-c, TPS-e/f, and TPS-g. HbTPSs were predicted to have functions in the cellular components, molecular functions, and biological processes. HbTPSs were involved in seven pathways, which were K14173, K14175, K15803, K04120, K04121, K17982, and K12742 in the secondary metabolite pathway prediction. Three-dimensional structures of HbTPSs of 7 pathways were predicted, and DDXXD, NSE/DTE, and EA(X)W conserved motifs near the binding sites were found. Cis-acting elements analysis showed that they had more cis-acting elements related to phytohormone responsiveness, which indicated that terpenoid biosynthesis might be related to phytohormone regulation. RNA-Seq analysis showed that different HbTPSs were expressed differentially in different tissues. This study's results help reveal the role of HbTPSs and their molecular mechanism and help resolve the regulatory mechanism of terpenoid biosynthesis in H.brasiliensis.


Assuntos
Alquil e Aril Transferases , Hevea , Hevea/genética , Hevea/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Filogenia , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Anal Methods ; 14(31): 3021-3032, 2022 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-35916160

RESUMO

Metamitron (MTM) is a typical and widely used triazine herbicide in agricultural production. Its moderate toxicity and high residue in the environment have deleterious impacts on human health. The establishment of a rapid and efficient MTM detection method is of great significance. In this study, a magnetic-bead SELEX (systematic evolution of ligands by exponential enrichment) system was developed to select the MTM aptamers with high affinity and specificity. Through 10 rounds of screening, six candidate aptamers with the highest abundance were obtained by high-throughput sequencing. The homology, secondary structure, and affinity analyses were performed. The aptamer named MTM-6 was selected as the optimal aptamer with the dissociation constant (Kd) value of 16 nM. Then, a colorimetric detection method for MTM based on aptamer MTM-6 and the aggregation of gold nanoparticles (AuNPs) induced by NaCl was established with a linear range from 20 to 1000 nM (R = 0.9966) and a limit of detection (LOD) of 4.58 nM. The average recovery rate of MTM in the application of actual aqueous samples ranged from 95.40 to 107.83% with a relative standard deviation (RSD) from 1.11 to 3.48%. With considerable sensitivity and specificity, this colorimetric aptasensor is convenient and efficient, and shows bright application potential in MTM detection in aqueous samples.


Assuntos
Aptâmeros de Nucleotídeos , Nanopartículas Metálicas , Aptâmeros de Nucleotídeos/química , Colorimetria/métodos , DNA de Cadeia Simples , Ouro/química , Humanos , Fenômenos Magnéticos , Nanopartículas Metálicas/química , Técnica de Seleção de Aptâmeros/métodos , Triazinas
6.
J Environ Sci (China) ; 114: 259-285, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35459491

RESUMO

Secondary organic aerosol (SOA) is a very important component of fine particulate matter (PM2.5) in the atmosphere. However, the simulations of SOA, which could help to elucidate the detailed mechanism of SOA formation and quantify the roles of various precursors, remains unsatisfactory, as SOA levels are frequently underestimated. It has been found that the performance of SOA formation models can be significantly improved by incorporating the emission and evolution of semivolatile and intermediate-volatility organic compounds (S/IVOCs). In order to explore the roles of S/IVOCs in SOA formation, this study reviews some simulation models which could consider S/IVOCs for SOA formation as well as the development of emission inventories of S/IVOCs and S/IVOC modules for SOA formation. In addition, the future research directions for simulations of the effect of S/IVOCs on SOA formation are suggested.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise , Volatilização
7.
Cancer Manag Res ; 13: 913-923, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33564266

RESUMO

INTRODUCTION: Studies have confirmed that parts of the non-coding genes in the human genome play an important role in the pathogenesis and metastasis of prostate cancer. Among them, long non-coding RNAs (lncRNAs) are vitally involved in the biological regulation of prostate cancer. In addition, lncRNAs are closely associated with the recurrence, metastasis and prognosis of prostate cancer. However, the molecular pathogenesis of lncRNAs in regulating cell growth and metastasis of prostate cancer remains unclear. Therefore, this study was designed to explore the function and mechanism of lncRNA RAMS11 in cell growth and metastasis of prostate cancer. METHODS: Prostate cancer and para-carcinoma tissue samples were obtained from 42 patients who were diagnosed from March 2013 to September 2014 at Quanzhou First Hospital Affiliated to Fujian Medical University. Microarray experiments and real-time polymerase chain reaction (PCR) measured the expression of lncRNA. RWPE-2, LNCap, PC3 and DU145 cells were used for an in vitro model. RESULTS: The expression of lncRNA RAMS11 was up-regulated in prostate cancer tissue samples. LncRNA RAMS11 promoted cell growth and metastasis of prostate cancer cells. Down-regulation of lncRNA RAMS11 attenuated cell growth and metastasis of prostate cancer cells. We also demonstrated that lncRNA RAMS11 bound to CBX4 to activate expression of Top2α. LncRNA RAMS11 promoted tumor growth of prostate cancer in the mouse model. The inhibition of CBX4 attenuated the pro-cancer effects of lncRNA AMS11 in prostate cancer cells, while the activation of Top2α attenuated the anti-cancer effects of si-lncRNA RAMS11 in prostate cancer cells. DISCUSSION: Our results indicated that lncRNA RAMS11 promoted cell growth and metastasis of prostate cancer by CBX4 complex via binding to Top2α, and might be developed for the treatment of prostate cancer.

8.
Anal Methods ; 13(1): 90-98, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33300899

RESUMO

A colorimetric method is described for detection of the antibiotic ciprofloxacin (CIP) in aqueous solutions based on an unmodified CIP-aptamer and gold nanoparticles (AuNPs), which are regarded as a probe and an indicator, respectively. In the absence of CIP, aptamers can hybridize with poly dimethyl diallyl ammonium chloride (PDDA) to form a 'duplex' structure through electrostatic interactions, and AuNPs remain dispersed in solution, leading to a red solution and an obvious absorption peak at 520 nm. Contrarily, the CIP-aptamer can specifically bind to CIP after the introduction of CIP into the solution. Then PDDA is thus free to aggregate AuNPs. The solution turns blue from red accordingly, presenting a strong absorption at 650 nm. Hence, the concentration of CIP can be quantified through the changes of the absorption. This sensitive and selective colorimetric method for CIP detection has a good linear response (R = 0.9935) in the 20 to 300 nM CIP concentration range, with a limit of detection (LOD) of 0.215 nM. Importantly, the proposed aptasensor demonstrates great application potential in CIP determination in aqueous samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Ciprofloxacina , Colorimetria , Ouro
9.
Environ Sci Pollut Res Int ; 27(30): 38321-38333, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32621199

RESUMO

Open-air burning of rice straw (RS) on sites after harvesting produces tremendous amounts of air pollutants in Southeast Asia. Additionally, cooking oil smoke (COS) from high-temperature frying is classified as "Probably carcinogenic to humans" (Group 2A) by the International Agency for Research on Cancer. To mitigate the air pollution from COS, RS was recycled to prepare activated carbon (AC), which was used as a bed filter (BF) packing material for COS removal, and to our best knowledge, this study is the first one. Besides, a negative air ionizer (NAI) was firstly utilized to enhance the removal efficiency (η) of COS particles. Other biomass waste, including tea leaves (TL), wood dust (WD), rice hulls (RH), and coffee grounds (CG), were also used as packing materials for comparison. Specific surface area and pore volume of the packing materials were determined by nitrogen adsorption/desorption isothermal. Laser airborne particle counters and volatile organic compound (VOC) monitors (photoionization detector) were utilized for real-time recording of the particle and VOC concentration of COS. Economic assessments for the control of COS was also conducted. For submicron particles, the removal efficiency of the BFs ranged from 0 to 98% and the AC filter had the highest quality factor. The NAI remarkably enhanced the η value and filter quality factor. For the removal of particles larger than 2.5 µm, all BFs had η > 96%. The removal efficiency of volatile organic compounds (VOCs) (ηVOC) of the test BFs ranged from 18.22 to 90.8%. The AC filter had the largest pore volume (0.432 cm3/g) and surface area (877 m2/g) among all packing materials, causing this filter to have the highest ηVOC and adsorption capacity (over 28.3 mg-VOCs/g-AC). The annual operating costs of the TL, WD, RH, CG, and AC filters were 319.4, 23.3, 29.1, 189.4, and 62.9 US$, respectively. Therefore, using RS to prepare an AC bed filter for the removal of COS is a practical and sustainable strategy for COS control.


Assuntos
Poluentes Atmosféricos/análise , Oryza , Biomassa , Carvão Vegetal , Estudos de Viabilidade
11.
Nature ; 565(7737): 82-85, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30455423

RESUMO

Levallois approaches are one of the best known variants of prepared-core technologies, and are an important hallmark of stone technologies developed around 300,000 years ago in Africa and west Eurasia1,2. Existing archaeological evidence suggests that the stone technology of east Asian hominins lacked a Levallois component during the late Middle Pleistocene epoch and it is not until the Late Pleistocene (around 40,000-30,000 years ago) that this technology spread into east Asia in association with a dispersal of modern humans. Here we present evidence of Levallois technology from the lithic assemblage of the Guanyindong Cave site in southwest China, dated to approximately 170,000-80,000 years ago. To our knowledge, this is the earliest evidence of Levallois technology in east Asia. Our findings thus challenge the existing model of the origin and spread of Levallois technologies in east Asia and its links to a Late Pleistocene dispersal of modern humans.


Assuntos
Arqueologia , Cavernas , Fósseis , Hominidae , Comportamento de Utilização de Ferramentas , África , Animais , China , Europa (Continente) , Ásia Oriental , História Antiga , Humanos , Fatores de Tempo
12.
J Cancer Res Ther ; 14(Supplement): S993-S997, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30539835

RESUMO

AIM OF STUDY: To further evaluate the influence of glutathione S-transferase M1 (GSTM1) and glutathione S-transferase T1 (GSTT1) null genotypes on bladder cancer risk, we conducted a meta-analysis in the Chinese population. MATERIALS AND METHODS: PubMed and Chinese databases were electronically searched through April 2016. RESULTS: Nine studies were included for our meta-analysis, involving 1646 bladder cancer cases and 1938 controls. In general, our findings indicated that a significant association existed between GSTM1-null genotype and the risk of bladder cancer in the studied Chinese population (odds ratio = 1.56, 95% confidence interval: 1.36-1.79). However, no significant association between GSTT1 polymorphism and bladder cancer was found. After stratification of the subgroup analyses by source of controls and geographical areas, a substantially elevated risk was revealed between GSTM1-null genotype and bladder cancer in the population-based studies and those conducted in South China and North China. CONCLUSION: Our meta-analysis suggested that GSTM1-null genotype is associated with an increased bladder cancer risk in the Chinese individuals.


Assuntos
Povo Asiático/genética , Predisposição Genética para Doença , Glutationa Transferase/genética , Neoplasias da Bexiga Urinária/genética , Humanos , Polimorfismo de Nucleotídeo Único
13.
Mikrochim Acta ; 185(7): 355, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29971570

RESUMO

A colorimetric method is presented for the determination of the antibiotic ofloxacin (OFL) in aqueous solution. It is based on the use of an aptamer and gold nanoparticles (AuNPs). In the absence of OFL, the AuNPs are wrapped by the aptamer and maintain dispersed even at the high NaCl concentrations. The solution with colloidally dispersed AuNPs remains red and has an absorption peak at 520 nm. In the presence of OFL, it will bind to the aptamer which is then released from the AuNPs. Hence, AuNPs will aggregate in the salt solution, and color gradually turns to blue, with a new absorption peak at 650 nm. This convenient and specific colorimetric assay for OFL has a linear response in the 20 to 400 nM OFL concentration range and a 3.4 nM detection limit. The method has a large application potential for OFL detection in environmental and biological samples. Graphical abstract Schematic of a sensitive and simple colorimetric aptasensor for ofloxacin (OFL) detection in tap water and synthesic urine. The assay is based on the salt-induced aggregation of gold nanoparticles which results in a color change from red to purple.

14.
Nature ; 559(7715): 608-612, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29995848

RESUMO

Considerable attention has been paid to dating the earliest appearance of hominins outside Africa. The earliest skeletal and artefactual evidence for the genus Homo in Asia currently comes from Dmanisi, Georgia, and is dated to approximately 1.77-1.85 million years ago (Ma)1. Two incisors that may belong to Homo erectus come from Yuanmou, south China, and are dated to 1.7 Ma2; the next-oldest evidence is an H. erectus cranium from Lantian (Gongwangling)-which has recently been dated to 1.63 Ma3-and the earliest hominin fossils from the Sangiran dome in Java, which are dated to about 1.5-1.6 Ma4. Artefacts from Majuangou III5 and Shangshazui6 in the Nihewan basin, north China, have also been dated to 1.6-1.7 Ma. Here we report an Early Pleistocene and largely continuous artefact sequence from Shangchen, which is a newly discovered Palaeolithic locality of the southern Chinese Loess Plateau, near Gongwangling in Lantian county. The site contains 17 artefact layers that extend from palaeosol S15-dated to approximately 1.26 Ma-to loess L28, which we date to about 2.12 Ma. This discovery implies that hominins left Africa earlier than indicated by the evidence from Dmanisi.


Assuntos
Hominidae , Animais , China , Fósseis , História Antiga , Paleontologia
15.
Proc Natl Acad Sci U S A ; 112(3): 702-6, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25561539

RESUMO

In the middle-to-late Holocene, Earth's monsoonal regions experienced catastrophic precipitation decreases that produced green to desert state shifts. Resulting hydrologic regime change negatively impacted water availability and Neolithic cultures. Whereas mid-Holocene drying is commonly attributed to slow insolation reduction and subsequent nonlinear vegetation-atmosphere feedbacks that produce threshold conditions, evidence of trigger events initiating state switching has remained elusive. Here we document a threshold event ca. 4,200 years ago in the Hunshandake Sandy Lands of Inner Mongolia, northern China, associated with groundwater capture by the Xilamulun River. This process initiated a sudden and irreversible region-wide hydrologic event that exacerbated the desertification of the Hunshandake, resulting in post-Humid Period mass migration of northern China's Neolithic cultures. The Hunshandake remains arid and is unlikely, even with massive rehabilitation efforts, to revert back to green conditions.

16.
J Hum Evol ; 78: 144-57, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25456822

RESUMO

The Homo erectus cranium from Gongwangling, Lantian County, Shaanxi Province is the oldest fossil hominin specimen from North China. It was found in 1964 in a layer below the Jaramillo subchron and was attributed to loess (L) L15 in the Chinese loess-palaeosol sequence, with an estimated age of ca. 1.15 Ma (millions of years ago). Here, we demonstrate that there is a stratigraphical hiatus in the Gongwangling section immediately below loess 15, and the cranium in fact lies in palaeosol (S) S22 or S23, the age of which is ca. 1.54-1.65 Ma. Closely spaced palaeomagnetic sampling at two sections at Gongwangling and one at Jiacun, 10 km to the north, indicate that the fossil layer at Gongwangling and a similar fossil horizon at Jiacun were deposited shortly before a short period of normal polarity above the Olduvai subchron. This is attributed to the Gilsa Event that has been dated elsewhere to ca. 1.62 Ma. Our investigations thus demonstrate that the Gongwangling cranium is slightly older than ca. 1.62 Ma, probably ca. 1.63 Ma, and significantly older than previously supposed. This re-dating now makes Gongwangling the second oldest site outside Africa (after Dmanisi) with cranial remains, and causes substantial re-adjustment in the early fossil hominin record in Eurasia.


Assuntos
Hominidae/anatomia & histologia , Crânio/anatomia & histologia , Animais , China , Fósseis , Paleontologia , Datação Radiométrica
17.
Int J Clin Exp Pathol ; 7(10): 7196-205, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25400817

RESUMO

In spite of the advances in the diagnosis and treatment of bladder cancer, the prognosis of bladder cancer remains relatively poor. As a result, it is vital to identify novel diagnostic and prognostic marker of bladder cancer. A growing volume of literature has implicated the vital role of long noncoding RNA in the development of cancer. GHET1, a recently identified lncRNA, was initially characterized in gastric cancer. However, its role in bladder cancer remains largely unknown. In this study, we demonstrated that GHET1 was upregulated in bladder cancer tissues compared to adjacent normal tissues and its over-expression correlates with tumor size, advanced tumor and lymph node status, and poor survival. GHET1 knockdown suppressed the proliferation and invasion of bladder cancer cells in vitro. In the meantime, inhibition of GHET1 reversed the epithelial-mesenchymal-transition in bladder cancer cell line. Taken together, our study suggests that the potential use of GHET1 as a prognostic marker and therapeutic target of bladder cancer.


Assuntos
Biomarcadores Tumorais/genética , Transformação Celular Neoplásica/genética , RNA Longo não Codificante/genética , Neoplasias da Bexiga Urinária/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Interferência de RNA , RNA Longo não Codificante/metabolismo , Fatores de Tempo , Transfecção , Carga Tumoral , Regulação para Cima , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
18.
J Hum Evol ; 59(5): 514-24, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20719358

RESUMO

The Xiaogushan cave site is one of the most important prehistoric sites in North China. The stone and bone artifacts found in the cave are similar to European contemporaneous artifacts. Cave deposits consist of five layers that have been dated from 46,353 ± 1179 to 4229 ± 135 cal. yr BP, using radiocarbon dating techniques on charcoal and bone samples collected from Layers 2-5. In this paper, optically stimulated luminescence (OSL) techniques were applied to date six samples taken from Layers 1-3. The luminescence properties of the fine-grained and coarse-grained quartz extracts indicate that the materials are suitable for OSL dating using a single-aliquot regeneration-dose (SAR) protocol. The OSL ages obtained are broadly consistent with the stratigraphy and the associated calibrated radiocarbon ages. The dating results show that the cave was first occupied by humans about 70 ka. The human occupation of the cave may be related to climate change. An occupation hiatus is inferred to between ∼ 17 to ∼ 10 ka. The stone and bone artifacts found in Layers 2 and 3 may indicate the Middle to Upper Paleolithic transitions in the region.


Assuntos
Fósseis , Sedimentos Geológicos/química , Medições Luminescentes/métodos , Datação Radiométrica , Animais , Osso e Ossos , China , Cronologia como Assunto , Hominidae , Humanos , Paleontologia , Tamanho da Partícula , Quartzo/química
19.
World J Gastroenterol ; 15(37): 4715-9, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19787835

RESUMO

AIM: To evaluate the efficacy and safety of Traditional Chinese Medicine (TCM) in the treatment of Helicobacter pylori (H. pylori) infection. METHODS: We electronically and manually searched electronic databases, references lists and conferences compilations, and included all randomized clinical trials comparing the treatment of H. pylori using TCM with proton pump inhibitor or colloidal bismuth subcitrate-based triple therapy as controls. The Jadad score was used to assess trial quality, H. pylori eradication rate and the incidence of side effects were taken as outcome measurements, and heterogeneity analysis, meta-analysis and funnel plot analysis were conducted. RESULTS: Sixteen trials were included. The Jadad scores of all the trials were not more than 2. Clinical heterogeneity and substantial statistical heterogeneity existed among the trials (P = 0.001, I(2) = 59%) and meta-analysis was not conducted. The average eradication rates following TCM and triple therapy were 72% and 78% and the incidence of side effects were 2% and 29%, respectively. The funnel plot was obviously asymmetric. CONCLUSION: Available evidence is not convincing enough to show that TCM has the same efficacy as triple therapy in H. pylori treatment. TCM may be safer than triple therapy. TCM should not be recommended as monotherapy in H. pylori infection.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Fitoterapia , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Medicina Tradicional Chinesa/efeitos adversos , Compostos Organometálicos/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
20.
J Hum Evol ; 52(4): 370-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17198721

RESUMO

A Plio-Pleistocene to Holocene faunal sequence has been recovered from four carefully excavated caves in the Bubing Basin, adjacent to the larger Bose Basin of South China. The caves vary in elevation; we suggest that the higher caves were formed and filled with sediments prior to the lower caves. The highest deposits, which are from Mohui Cave, contain hominoid teeth and other fossilized remains of mammalian taxa most similar to late Pliocene and early Pleistocene faunas. Wuyun Cave ( approximately 50m lower in elevation than Mohui) contains a late middle Pleistocene fauna, which is supported by U-series age constraints from 350 to 200ka. Lower Pubu Cave ( approximately 23m below Wuyun) is assigned to the late Pleistocene, while the Cunkong Cave (the lowest, approximately 2m lower elevation than Lower Pubu) preserves a Holocene fauna. The four faunal assemblages indicate species-level changes in Ailuropoda, Stegodon, and Sus, the appearance of Elephas, the local disappearance of Stegodon, and the migration of Equus hemionus to South China. These initial results of our work call into question the continued value of the Stegodon/Ailuropoda Fauna, a category long used to characterize the Pleistocene faunas of South China. Excavation of karstic caves of varying elevation within the basins of South China holds promise for defining local sequences of mammalian fossils that can be used to investigate faunal variations related to climate change, biogeographic events, and evolutionary change over the past two million years. Stable isotopic analysis of a small sample of mammalian teeth from Bubing Basin caves is consistent with 100% C(3) vegetation in the Bubing/Bose region, with certain delta(13)C values consistent with a canopied woodland or forest. A preliminary assessment of the hominoid teeth indicates the presence of diverse molar and premolar morphologies including dental remains of Gigantopithecus blacki and a sample with similarities to the teeth reported from Longgupo.


Assuntos
Fósseis , Mamíferos , Dente , Animais , Isótopos de Carbono/análise , China , Hominidae , Dente/química
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