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1.
Int Urol Nephrol ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632173

RESUMEN

INTRODUCTION: The commonly used clinical indicators are not sensitive and comprehensive enough to evaluate the early staging of chronic kidney disease (CKD). This study aimed to evaluate the differences in arterial spin labeling (ASL) and blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-MRI) parameter values among patients at various stages of chronic kidney disease and healthy individuals. METHODS: Electronic databases PubMed, Web of Science, Cochrane, and Embase were searched from inception to March 29, 2024, to identify relevant studies on ASL and BOLD in CKD. The renal blood flow (RBF) and apparent relaxation rate (R2*) values were obtained from healthy individuals and patients with various stages of CKD. The meta-analysis was conducted using STATA version 12.0. The random-effects model was used to obtain estimates of the effects, and the results were expressed as 95% confidence intervals (CIs) and mean differences (MDs) of continuous variables. RESULTS: A total of 18 published studies were included in this meta-analysis. The cortical RBF and R2* values and medulla RBF values were considerably distinct between patients with various stages of CKD and healthy controls (MD, - 78.162; 95% CI, - 85.103 to - 71.221; MD, 2.440; 95% CI, 1.843 to 3.037; and MD, - 36.787; 95% CI, - 47.107 to - 26.468, respectively). No obvious difference in medulla R2* values was noted between patients with various stages of CKD and healthy controls (MD, - 1.475; 95% CI, - 4.646 to 1.696). CONCLUSION: ASL and BOLD may provide complementary and distinct information regarding renal function and could potentially be used together to gain a more comprehensive understanding of renal physiology.

2.
Elife ; 122024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38457350

RESUMEN

Studies of climate variation commonly rely on chemical and isotopic changes recorded in sequentially produced growth layers, such as in corals, shells, and tree rings, as well as in accretionary deposits-ice and sediment cores, and speleothems. Oxygen isotopic compositions (δ18O) of tooth enamel are a direct method of reconstructing environmental variation experienced by an individual animal. Here, we utilize long-forming orangutan dentitions (Pongo spp.) to probe recent and ancient rainfall trends on a weekly basis over ~3-11 years per individual. We first demonstrate the lack of any consistent isotopic enrichment effect during exclusive nursing, supporting the use of primate first molar teeth as environmental proxies. Comparisons of δ18O values (n=2016) in twelve molars from six modern Bornean and Sumatran orangutans reveal a high degree of overlap, with more consistent annual and bimodal rainfall patterns in the Sumatran individuals. Comparisons with fossil orangutan δ18O values (n=955 measurements from six molars) reveal similarities between modern and late Pleistocene fossil Sumatran individuals, but differences between modern and late Pleistocene/early Holocene Bornean orangutans. These suggest drier and more open environments with reduced monsoon intensity during this earlier period in northern Borneo, consistent with other Niah Caves studies and long-term speleothem δ18O records in the broader region. This approach can be extended to test hypotheses about the paleoenvironments that early humans encountered in southeast Asia.


When an animal drinks water, two naturally occurring variants of oxygen ­ known as oxygen-18 and oxygen-16 ­ are incorporated into its growing teeth. The ratio of these variants in water changes with temperature, rainfall and other environmental conditions and therefore can provide a record of the climate during an animal's life. Teeth tend to be well preserved as fossils, which makes it possible to gain insights into this climate record even millions of years after an animal's death. Orangutans are highly endangered great apes that today live in rainforests on the islands of Borneo and Sumatra. During a period of time known as the Pleistocene (around 2.6 million years to 12,000 years ago), these apes were more widely spread across Southeast Asia. Climate records from this area in the time before human-induced climate change are somewhat limited. Therefore, fossilized orangutan teeth offer a possible way to investigate past seasonal rainfall patterns and gain insight into the kind of environments early humans would have encountered. To address this question, Smith et al. measured oxygen-18 and oxygen-16 variants in thin slices of modern-day orangutan teeth using a specialized analytical system. This established that the teeth showed seasonal patterns consistent with recent rainfall trends, and that the ratio of these oxygen variants did not appear to be impacted by milk intake in young orangutans. These findings indicated that the oxygen variants could be a useful proxy for predicting prehistoric weather patterns from orangutan teeth. Further measurements of teeth from fossilized Sumatran orangutans showed broadly similar rainfall patterns to those of teeth from modern-day orangutans. On the other hand, fossilized teeth from Borneo suggested that the environment used to be drier, with less intense wet seasons. The approach developed by Smith et al. provides an opportunity for scientists to leverage new fossil discoveries as well as existing collections to investigate past environments. This could allow future research into how climate variation may have influenced the spread of early humans through the region, as well as the evolution of orangutans and other endangered animals.


Asunto(s)
Hominidae , Pongo abelii , Diente , Animales , Humanos , Pongo pygmaeus , Asia Sudoriental
3.
Nature ; 625(7995): 535-539, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38200315

RESUMEN

The largest ever primate and one of the largest of the southeast Asian megafauna, Gigantopithecus blacki1, persisted in China from about 2.0 million years until the late middle Pleistocene when it became extinct2-4. Its demise is enigmatic considering that it was one of the few Asian great apes to go extinct in the last 2.6 million years, whereas others, including orangutan, survived until the present5. The cause of the disappearance of G. blacki remains unresolved but could shed light on primate resilience and the fate of megafauna in this region6. Here we applied three multidisciplinary analyses-timing, past environments and behaviour-to 22 caves in southern China. We used 157 radiometric ages from six dating techniques to establish a timeline for the demise of G. blacki. We show that from 2.3 million years ago the environment was a mosaic of forests and grasses, providing ideal conditions for thriving G. blacki populations. However, just before and during the extinction window between 295,000 and 215,000 years ago there was enhanced environmental variability from increased seasonality, which caused changes in plant communities and an increase in open forest environments. Although its close relative Pongo weidenreichi managed to adapt its dietary preferences and behaviour to this variability, G. blacki showed signs of chronic stress and dwindling populations. Ultimately its struggle to adapt led to the extinction of the greatest primate to ever inhabit the Earth.


Asunto(s)
Extinción Biológica , Fósiles , Hominidae , Animales , Cuevas , China , Dieta/veterinaria , Bosques , Hominidae/clasificación , Plantas , Pongo , Datación Radiométrica , Estaciones del Año , Factores de Tiempo
5.
Eur J Radiol Open ; 10: 100476, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36793772

RESUMEN

Purpose: To develop models based on radiomics and genomics for predicting the histopathologic nuclear grade with localized clear cell renal cell carcinoma (ccRCC) and to assess whether macro-radiomics models can predict the microscopic pathological changes. Method: In this multi-institutional retrospective study, a computerized tomography (CT) radiomic model for nuclear grade prediction was developed. Utilizing a genomics analysis cohort, nuclear grade-associated gene modules were identified, and a gene model was constructed based on top 30 hub mRNA to predict the nuclear grade. Using a radiogenomic development cohort, biological pathways were enriched by hub genes and a radiogenomic map was created. Results: The four-features-based SVM model predicted nuclear grade with an area under the curve (AUC) score of 0.94 in validation sets, while a five-gene-based model predicted nuclear grade with an AUC of 0.73 in the genomics analysis cohort. A total of five gene modules were identified to be associated with the nuclear grade. Radiomic features were only associated with 271 out of 603 genes in five gene modules and eight top 30 hub genes. Differences existed in the enrichment pathway between associated and un-associated with radiomic features, which were associated with two genes of five-gene signatures in the mRNA model. Conclusion: The CT radiomics models exhibited higher predictive performance than mRNA models. The association between radiomic features and mRNA related to nuclear grade is not universal.

6.
Eur J Radiol ; 158: 110640, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36525703

RESUMEN

PURPOSE: The purpose of this study was to evaluate the methodological quality of radiomics-based studies for noninvasive, preoperative prediction of Kirsten rat sarcoma (KRAS) mutations in patients with colorectal cancer; furthermore, we systematically evaluate the diagnostic accuracy of predicting models. METHODS: We systematically searched PubMed, Embase, Cochrane Library and Web of Science databases up to 20 April 2022 for eligible studies. The methodological quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) and Radiomics Quality Score (RQS) tools. A meta-analysis of studies on the prediction of KRAS status in colorectal cancer patients was performed. RESULT: Twenty-nine studies were identified in the systematic review, including three studies on the prediction of KRAS status in colorectal cancer liver metastases. All studies had an average RQS score of 9.55 (26.5% of the total score), ranging from 3 to 17. Most studies demonstrated a low or unclear risk of bias in the domains of QUADAS-2. Nineteen studies were included in the meta-analysis, mostly imaged with magnetic resonance imaging (MRI), followed by computed tomography (CT), positron emission tomography-CT (PET/CT). With pooled sensitivity, specificity and area under the curve (AUC) of the training cohorts were 0.80(95% confidence interval(CI), 0.75-0.84), 0.80(95% CI, 0.74-0.85) and 0.87(95% CI, 0.84-0.90),respectively. The pooled sensitivity, specificity, and AUC for the validation cohorts (13 studies) were 0.78(95% CI, 0.71-0.84), 0.84(95% CI, 0.74-0.90), and 0.86(95% CI, 0.83-0.89), respectively. CONCLUSION: Radiomics is a potential noninvasive technology that has a moderate preoperative diagnosis and prediction effect on KRAS mutations. However, it has not been implemented as a clinical decision-making tool. Future researchers should pay more attention to the methodological quality of the study and further externally validate the model using multicenter datasets.


Asunto(s)
Neoplasias Colorrectales , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Tomografía Computarizada por Rayos X/métodos , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Mutación , Estudios Multicéntricos como Asunto
7.
Sci Rep ; 12(1): 20214, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36424387

RESUMEN

Antiphase behaviour of monsoon systems in alternate hemispheres is well established at yearly and orbital scales in response to alternating sensible heating of continental landmasses. At intermediate timescales without a sensible heating mechanism both in-phase and antiphase behaviours of northern and southern hemisphere monsoon systems are recorded at different places and timescales. At present, there is no continuous, high resolution, precisely dated record of millennial-scale variability of the Indonesian-Australian monsoon during the last glacial period with which to test theories of paleomonsoon behaviour. Here, we present an extension of the Liang Luar, Flores, speleothem δ18O record of past changes in southern hemisphere summer monsoon intensity back to 55.7 kyr BP. Negative δ18O excursions (stronger monsoon) occur during Heinrich events whereas positive excursions (weaker monsoon) occur during Dansgaard-Oeschger interstadials-a first order antiphase relationship with northern hemisphere summer monsoon records. An association of negative δ18O excursions with speleothem growth phases in Liang Luar suggests that these stronger monsoons are related to higher rainfall amounts. However, the response to millennial-scale variability is inconsistent, including a particularly weak response to Heinrich event 3. We suggest that additional drivers such as underlying orbital-scale variability and drip hydrology influence the δ18O response.


Asunto(s)
Tormentas Ciclónicas , Temperatura , Indonesia , Australia , Estaciones del Año
8.
Front Oncol ; 12: 1026216, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36313696

RESUMEN

Purpose: The purpose of this study was to evaluate the diagnostic accuracy of artificial intelligence (AI) models with magnetic resonance imaging(MRI) in predicting pathological complete response(pCR) to neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer. Furthermore, assessed the methodological quality of the models. Methods: We searched PubMed, Embase, Cochrane Library, and Web of science for studies published before 21 June 2022, without any language restrictions. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) and Radiomics Quality Score (RQS) tools were used to assess the methodological quality of the included studies. We calculated pooled sensitivity and specificity using random-effects models, I2 values were used to measure heterogeneity, and subgroup analyses to explore potential sources of heterogeneity. Results: We selected 21 papers for inclusion in the meta-analysis from 1562 retrieved publications, with a total of 1873 people in the validation groups. The meta-analysis showed that AI models based on MRI predicted pCR to nCRT in patients with rectal cancer: a pooled area under the curve (AUC) 0.91 (95% CI, 0.88-0.93), sensitivity of 0.82(95% CI,0.71-0.90), pooled specificity 0.86(95% CI,0.80-0.91). In the subgroup analysis, the pooled AUC of the deep learning(DL) model was 0.97, the pooled AUC of the radiomics model was 0.85; the pooled AUC of the combined model with clinical factors was 0.92, and the pooled AUC of the radiomics model alone was 0.87. The mean RQS score of the included studies was 10.95, accounting for 30.4% of the total score. Conclusions: Radiomics is a promising noninvasive method with high value in predicting pathological response to nCRT in patients with rectal cancer. DL models have higher predictive accuracy than radiomics models, and combined models incorporating clinical factors have higher diagnostic accuracy than radiomics models alone. In the future, prospective, large-scale, multicenter investigations using radiomics approaches will strengthen the diagnostic power of pCR. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42021285630.

9.
Eur J Radiol Open ; 9: 100438, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35996746

RESUMEN

Objectives: When diagnosing Coronavirus disease 2019(COVID-19), radiologists cannot make an accurate judgments because the image characteristics of COVID-19 and other pneumonia are similar. As machine learning advances, artificial intelligence(AI) models show promise in diagnosing COVID-19 and other pneumonias. We performed a systematic review and meta-analysis to assess the diagnostic accuracy and methodological quality of the models. Methods: We searched PubMed, Cochrane Library, Web of Science, and Embase, preprints from medRxiv and bioRxiv to locate studies published before December 2021, with no language restrictions. And a quality assessment (QUADAS-2), Radiomics Quality Score (RQS) tools and CLAIM checklist were used to assess the quality of each study. We used random-effects models to calculate pooled sensitivity and specificity, I2 values to assess heterogeneity, and Deeks' test to assess publication bias. Results: We screened 32 studies from the 2001 retrieved articles for inclusion in the meta-analysis. We included 6737 participants in the test or validation group. The meta-analysis revealed that AI models based on chest imaging distinguishes COVID-19 from other pneumonias: pooled area under the curve (AUC) 0.96 (95 % CI, 0.94-0.98), sensitivity 0.92 (95 % CI, 0.88-0.94), pooled specificity 0.91 (95 % CI, 0.87-0.93). The average RQS score of 13 studies using radiomics was 7.8, accounting for 22 % of the total score. The 19 studies using deep learning methods had an average CLAIM score of 20, slightly less than half (48.24 %) the ideal score of 42.00. Conclusions: The AI model for chest imaging could well diagnose COVID-19 and other pneumonias. However, it has not been implemented as a clinical decision-making tool. Future researchers should pay more attention to the quality of research methodology and further improve the generalizability of the developed predictive models.

10.
Nat Commun ; 13(1): 2557, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35581187

RESUMEN

The Pleistocene presence of the genus Homo in continental Southeast Asia is primarily evidenced by a sparse stone tool record and rare human remains. Here we report a Middle Pleistocene hominin specimen from Laos, with the discovery of a molar from the Tam Ngu Hao 2 (Cobra Cave) limestone cave in the Annamite Mountains. The age of the fossil-bearing breccia ranges between 164-131 kyr, based on the Bayesian modelling of luminescence dating of the sedimentary matrix from which it was recovered, U-series dating of an overlying flowstone, and U-series-ESR dating of associated faunal teeth. Analyses of the internal structure of the molar in tandem with palaeoproteomic analyses of the enamel indicate that the tooth derives from a young, likely female, Homo individual. The close morphological affinities with the Xiahe specimen from China indicate that they belong to the same taxon and that Tam Ngu Hao 2 most likely represents a Denisovan.


Asunto(s)
Hominidae , Animales , Teorema de Bayes , Femenino , Fósiles , Hominidae/anatomía & histología , Humanos , Laos , Diente Molar
11.
Zhongguo Zhen Jiu ; 42(5): 559-62, 2022 May 12.
Artículo en Chino | MEDLINE | ID: mdl-35543949

RESUMEN

"Unblocking fu organs" is one of the essential principles of Ma's warm moxibustion technique, characterized as "dredging" and "harmonizing" for either deficiency or excess condition. Under the guidance of this therapeutic thought, the acupoints for moxibustion are mainly selected from the middle and lower parts of the body. Regarding the therapeutic approach, the acupoint prescription for moxibustion should be formed in line with warming and promoting circulation of fu organs; the moxibustion degree should be specially considered, in which, the mild moxibustion is recommended to induce promoting action; and the systematic moxibustion technique should be the root for dredging fu organs and regulating zang organs. Ma's mild moxibustion technique stresses on removing the obstruction of fu organs and emphasizes promoting the qi activity of sanjiao (triple energizer) and regulating the balance of five zang organs.


Asunto(s)
Terapia por Acupuntura , Moxibustión , Puntos de Acupuntura , Etnicidad , Humanos , Hiperplasia , Moxibustión/métodos
12.
Zhonghua Nan Ke Xue ; 28(6): 501-505, 2022 Jun.
Artículo en Chino | MEDLINE | ID: mdl-37477466

RESUMEN

OBJECTIVE: To observe the recovery of urinary continence through postoperative rehabilitation training after robot-assisted laparoscopic radical prostatectomy (RARP) versus that after traditional laparoscopic radical prostatectomy (LRP). METHODS: This study included 64 cases of urinary incontinence after surgically treated for PCa from May 2017 to February 2021, 32 by RARP and the other 32 by LRP as the controls. All the patients received standard urinary continence rehabilitation training and routine nursing care postoperatively, followed by comparison of the rate and time of urinary incontinence recovery and the patients' scores on the quality of life (QOL) and satisfaction with treatment between the two groups. RESULTS: There were no statistically significant differences in age, PSA level or pathological stage between the two groups of patients (P > 0.05). After standard urinary continence rehabilitation training, the patients in the RARP group, compared with those in the LRP control, showed a lower grade of urinary incontinence (χ2 = 6.483, P = 0.039), a shorter mean duration of urinary incontinence per day, an earlier recovery of urinary continence (χ2 = 4.73, P = 0.030 at 1-3 months; χ2 = 12.696, P < 0.001 at 4-6 months), a higher rate of overall recovery (χ2 = 13.396, P = 0.004), and higher scores on QOL and satisfaction with treatment. CONCLUSION: RARP can effectively improve the recovery from postoperative urinary incontinence in PCa patients.


Asunto(s)
Laparoscopía , Neoplasias de la Próstata , Procedimientos Quirúrgicos Robotizados , Robótica , Incontinencia Urinaria , Masculino , Humanos , Calidad de Vida , Resultado del Tratamiento , Incontinencia Urinaria/cirugía , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/patología , Prostatectomía/efectos adversos , Recuperación de la Función
13.
Sci Total Environ ; 809: 151176, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-34699835

RESUMEN

Reefs are biogenic structures that result in three-dimensional accumulations of calcium carbonate. Over geological timescales, a positive balance between the production and accumulation of calcium carbonate versus erosional and off-reef transport processes maintains positive net accretion on reefs. Yet, how ecological processes occurring over decadal timescales translate to the accumulation of geological structures is poorly understood, in part due to a lack of studies with detailed time-constrained chronologies of reef accretion over decades to centuries. Here, we combined ecological surveys of living reefs with palaeoecological reconstructions and high-precision radiometric (U-Th) age-dating of fossil reefs represented in both reef sediment cores and surficial dead in situ corals, to reconstruct the history of community composition and carbonate accumulation across the central and southern Saudi Arabian Red Sea throughout the late Holocene. We found that reefs were primarily comprised of thermally tolerant massive Porites colonies, creating a consolidated coral framework, with unconsolidated branching coral rubble accumulating among massive corals on shallow (5-8 m depth) exposed (windward), and gently sloping reef slopes. These unconsolidated reef rubble fields were formed primarily from ex situ Acropora and Pocillopora coral fragments, infilled post deposition within a sedimentary matrix. Bayesian age-depth models revealed a process of punctuated deposition of post-mortem coral fragments transported from adjacent reef environments. That a large portion of Saudi Arabian Red Sea reef slopes is driven by allochthonous deposition (transportation) has important implications for modeling carbonate budgets and reef growth. In addition, a multi-decadal lag exists between the time of death for branching in situ coral and incorporation into the unconsolidated reef rubble. This indicates that recent climate related degradation in the 21st century has not had an immediately negative effect on reef building processes affecting a large portion of the reef area in the Saudi Arabian Red Sea.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Teorema de Bayes , Océano Índico , Arabia Saudita
14.
Zhonghua Nan Ke Xue ; 27(4): 301-308, 2021 Apr.
Artículo en Chino | MEDLINE | ID: mdl-34914211

RESUMEN

OBJECTIVE: To investigate the molecular mechanism of hsa_circ_0005221 regulating the progression of PCa through the miR-339-5p/STAT5a pathway. METHODS: Localizations of hsa_circ_0005221 and miR-339-5p in cells were detected by nuclear-cytoplasmic isolation. MiRNA-339-5p was selected as the target miRNA bound to hsa_circ_0005221 by RNA pull-down assay. The binding site of the luciferase reporter gene was predicted by software and the binding capability of miR-339-5p validated by luciferase assay. The expression of hsa_circ_0005221 in the prostatic epithelial and PCa cells was determined by qPCR. The hsa_circ_0005221-overexpressed plasmid and siRNA were transfected into the PCa cells for measurement of their proliferation, invasion and migration abilities and the levels of epithelial-mesenchymal transformation (EMT) and apoptosis. After knockdown of hsa_circ_0005221 and transfection of miR-339-5p mimics and miR-339-5p inhibitor, the proliferation, invasion and migration abilities of the DU145 and LNCaP cells were detected, and so were the levels of the EMT signature protein, STAT5a and cell apoptosis. RESULTS: The expression of hsa_circ_0005221 was significantly higher in the PCa than in the prostatic epithelial cells. Nuclear-cytoplasmic isolation experiments showed that hsa_circ_0005221 and miR-339-5p were mainly located in the cytoplasm. The proliferation, invasion and migration abilities and EMT were decreased and the apoptosis increased in the DU145 and LNCaP cells with knockdown of hsa_circ_0005221, which was just the reverse in those with overexpressed hsa_circ_0005221. Among the top 5 miRNAs predicted by software, miR-339-5p, miR-17 and miR-520h were shown by pull-down assay to be bound to hsa_circ_0005221, with most obvious changes in miR-339-5p when hsa_circ_0005221 knocked down or overexpressed. Luciferase reporter gene assay showed the binding of hsa_circ_0005221 to miR-339-5p. Knockdown of hsa_circ_0005221 and transfection of miR-339-5p mimics into the DU145 and LNCaP cells significantly reduced the proliferation, invasion and migration abilities of the cells and the N-cad level, increased their apoptosis and E-cad level, and up-regulated the expression of STAT5a, while overexpression of hsa_circ_0005221 and transfection of miR-339-5p mimics induced just the opposite effects. CONCLUSIONS: Hsa_circ_0005221 enhances the progression of prostate cancer through the miR-339-5p/STAT5a pathway.


Asunto(s)
MicroARNs , Neoplasias de la Próstata , ARN Circular/genética , Factor de Transcripción STAT5 , Humanos , Masculino , MicroARNs/genética , Pelvis , Próstata , Neoplasias de la Próstata/genética , ARN Interferente Pequeño , Factor de Transcripción STAT5/genética , Proteínas Supresoras de Tumor
15.
PLoS One ; 16(9): e0257273, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34587195

RESUMEN

Major gaps remain in our knowledge of the early history of Homo sapiens in Wallacea. By 70-60 thousand years ago (ka), modern humans appear to have entered this distinct biogeographical zone between continental Asia and Australia. Despite this, there are relatively few Late Pleistocene sites attributed to our species in Wallacea. H. sapiens fossil remains are also rare. Previously, only one island in Wallacea (Alor in the southeastern part of the archipelago) had yielded skeletal evidence for pre-Holocene modern humans. Here we report on the first Pleistocene human skeletal remains from the largest Wallacean island, Sulawesi. The recovered elements consist of a nearly complete palate and frontal process of a modern human right maxilla excavated from Leang Bulu Bettue in the southwestern peninsula of the island. Dated by several different methods to between 25 and 16 ka, the maxilla belongs to an elderly individual of unknown age and sex, with small teeth (only M1 to M3 are extant) that exhibit severe occlusal wear and related dental pathologies. The dental wear pattern is unusual. This fragmentary specimen, though largely undiagnostic with regards to morphological affinity, provides the only direct insight we currently have from the fossil record into the identity of the Late Pleistocene people of Sulawesi.


Asunto(s)
Arqueología/métodos , Restos Mortales , Fósiles , Anciano , Animales , Hominidae , Humanos , Indonesia , Nueva Guinea , Nueva Gales del Sur , Queensland , Diente , Desgaste de los Dientes
16.
Proc Natl Acad Sci U S A ; 118(29)2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34230097

RESUMEN

Preexploitation shark baselines and the history of human impact on coral reef-associated shark communities in the Caribbean are tpoorly understood. We recovered shark dermal denticles from mid-Holocene (∼7 ky ago) and modern reef sediments in Bocas del Toro, Caribbean Panama, to reconstruct an empirical shark baseline before major human impact and to quantify how much the modern shark community in the region had shifted from this historical reference point. We found that denticle accumulation rates, a proxy for shark abundance, declined by 71% since the mid-Holocene. All denticle morphotypes, which reflect shark community composition, experienced significant losses, but those morphotypes found on fast-swimming, pelagic sharks (e.g., families Carcharhinidae and Sphyrnidae) declined the most. An analysis of historical records suggested that the steepest decline in shark abundance occurred in the late 20th century, coinciding with the advent of a targeted shark fishery in Panama. Although the disproportionate loss of denticles characterizing pelagic sharks was consistent with overfishing, the large reduction in denticles characterizing demersal species with low commercial value (i.e., the nurse shark Ginglymostoma cirratum) indicated that other stressors could have exacerbated these declines. We demonstrate that the denticle record can reveal changes in shark communities over long ecological timescales, helping to contextualize contemporary abundances and inform shark management and ecology.


Asunto(s)
Escamas de Animales , Arrecifes de Coral , Fósiles , Tiburones/fisiología , Escamas de Animales/citología , Escamas de Animales/fisiología , Animales , Región del Caribe , Conservación de los Recursos Naturales , Sedimentos Geológicos/química , Actividades Humanas , Humanos , Panamá , Tiburones/clasificación , Factores de Tiempo
17.
Food Res Int ; 144: 110331, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34053534

RESUMEN

The link between the gut microbiome and bone health has begun to attract widespread interest in recent years. The gut microbiome are vital in many diseases involving bone loss. Probiotics, prebiotics, and dietary supplements have been suggested to protect bone health by altering the composition of the gut microbiota. Notably, studying the relationship between the gut microbiome and bone health can provide a basis for the prevention and treatment of bone diseases. This review focuses on the link between the gut microbiome and bone diseases, exploring current knowledge of the mechanisms by which gut bacteria affect bone health. In addition, the influences of dietary supplements on the interactions between the gut microbiome and bone health are discussed. This knowledge will promote new ideas for gut microbiota-mediated dietary interventions in patients with bone diseases.


Asunto(s)
Microbioma Gastrointestinal , Probióticos , Densidad Ósea , Dieta , Humanos , Prebióticos
18.
Sci Adv ; 7(3)2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33523879

RESUMEN

Indonesia harbors some of the oldest known surviving cave art. Previously, the earliest dated rock art from this region was a figurative painting of a Sulawesi warty pig (Sus celebensis). This image from Leang Bulu' Sipong 4 in the limestone karsts of Maros-Pangkep, South Sulawesi, was created at least 43,900 years ago (43.9 ka) based on Uranium-series dating. Here, we report the Uranium-series dating of two figurative cave paintings of Sulawesi warty pigs recently discovered in the same karst area. The oldest, with a minimum age of 45.5 ka, is from Leang Tedongnge. The second image, from Leang Balangajia 1, dates to at least 32 ka. To our knowledge, the animal painting from Leang Tedongnge is the earliest known representational work of art in the world. There is no reason to suppose, however, that this early rock art is a unique example in Island Southeast Asia or the wider region.

19.
iScience ; 23(10): 101575, 2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33083741

RESUMEN

Accurately determining the age of hydrothermal ore deposits is difficult, because of lack of suitable mineral chronometers and techniques. Here we present the first LA-MC-ICPMS U-Pb age of carbonates from hydrothermal Sb deposits. Three stages of hydrothermal carbonates from the giant South China Sb metallogenic belt were identified: (1) pre-ore dolomite (Dol-I), (2) syn-ore calcite (Cal-II), and (3) post-ore calcite (Cal-III). The U and Pb isotopic data show that Cal-II yielded a lower intercept age of 115.3 ± 1.5 Ma (MSWD = 2.0), suggesting a Sb mineralization that corresponds to an extension event occurred during the early Cretaceous in South China. Although Cal-III yielded an age of 60.0 ± 0.9 Ma (MSWD = 1.5), indicating a potential tectonothermal event occurred in this belt during the early Cenozoic. Hence, in situ U-Pb dating of calcite offers a new way to determine the age of hydrothermal ore deposits.

20.
PLoS One ; 15(9): e0239267, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32997690

RESUMEN

Caribbean Acropora spp. corals have undergone a decline in cover since the second half of the twentieth century. Loss of these architecturally complex and fast-growing corals has resulted in significant, cascading changes to the character, diversity, and available eco-spaces of Caribbean reefs. Few thriving Acropora spp. populations exist today in the Caribbean and western North Atlantic seas, and our limited ability to access data from reefs assessed via long-term monitoring efforts means that reef scientists are challenged to determine resilience and longevity of existing Acropora spp. reefs. Here we used multiple dating methods to measure reef longevity and determine whether Coral Gardens Reef, Belize, is a refuge for Acropora cervicornis against the backdrop of wider Caribbean decline. We used a new genetic-aging technique to identify sample sites, and radiocarbon and high-precision uranium-thorium (U-Th) dating techniques to test whether one of the largest populations of extant A. cervicornis in the western Caribbean is newly established after the 1980s, or represents a longer-lived, stable population. We did so with respect for ethical sampling of a threatened species. Our data show corals ranging in age from 1910 (14C) or 1915 (230Th) to at least November 2019. While we cannot exclude the possibility of short gaps in the residence of A. cervicornis earlier in the record, the data show consistent and sustained living coral throughout the 1980s and up to at least 2019. We suggest that Coral Gardens has served as a refuge for A. cervicornis and that identifying other, similar sites may be critical to efforts to grow, preserve, conserve, and seed besieged Caribbean reefs.


Asunto(s)
Antozoos/fisiología , Conservación de los Recursos Naturales , Arrecifes de Coral , Refugio de Fauna , Animales , Belice , Región del Caribe , Especies en Peligro de Extinción , Dinámica Poblacional
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