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Landscape-oriented approaches in archaeology have moved beyond site-based research to interpret how people have engaged with, modified, and constructed the environment and how the legacies of these activities continue to influence land use. In the Maya Lowlands, landscape archaeology is related to the analysis of settlement patterns, households, agricultural intensification, and water management. The increasing availability of LiDAR data has revolutionized the mapping of archaeological landscapes under vegetation, especially in tropical environments like the Maya Lowlands, but researchers still emphasize site-oriented settlement densities and infrastructure. Furthermore, the accessibility of drone-based LiDAR platforms has the potential to collect data across several seasons or years to facilitate change detection. In this paper, we compare three LiDAR datasets collected from 2018 to 2023, using both occupied and unoccupied airborne systems. The landscape surrounding the archaeological site of El Infiernito, Chiapas, Mexico near the Classic period (AD 250–800) dynastic capital of Piedras Negras, Guatemala was selected to compare these LiDAR datasets in the context of prior, extensive ground-based fieldwork. These data were used to interpret the built environment, land use, hydrology, landscapes of movement, and other infrastructure constructed and modified by several communities beginning in the Late Preclassic period (400 BC–AD 250) to the present. When used alongside systematic survey and ground verification, the combination of several LiDAR platforms to collect data across different seasons at El Infiernito enhanced the understanding of the spatial distribution of archaeological sites and features across the karst landscape. [ABSTRACT FROM AUTHOR]

Constructed landscapes are composed of diverse communities, representing different social strata and perspectives of a place. In turn, the risks associated with inhabiting unpredictable environments are disproportionately felt across urban and rural landscapes. The mitigation and management of risks often fall on farming and smallholder communities, influencing decentralized strategies. These themes are explored in an archaeological context surrounding the confluence of the Upper Usumacinta and Lacantún Rivers in the neotropical Maya lowlands of Chiapas, Mexico. LiDAR data collected recently with the GatorEye unoccupied aerial vehicle (UAV) and NASA's GLiHT system have aided in the mapping of the archaeological urban centre of Benemérito de las Américas, Primera Sección and the surrounding landscape. These data have revealed coupled settlement with land management, in the form of wetland fields, reservoirs, and riverways, emphasizing the interconnectivity of household practice and land use in the region. [ABSTRACT FROM AUTHOR]

El artículo discute las excavaciones arqueológicas en los sitios de Aguada Fénix y San Lorenzo para determinar el asentamiento temprano de los mayas y el desarrollo de la cultura maya con un enfoque en la relación entre los pueblos maya y olmeca.

Background: Reports of higher rates of medical errors in the month of July have generated concern regarding major surgery at academic institutions early in the yearly promotion cycle. This study was designed to evaluate perioperative outcomes in patients undergoing pancreaticoduodenectomy (PD) at different times of the year.Materials and Methods: Outcomes were retrospectively evaluated for patients treated in July versus the rest of the year and in the first quarter (July-September) versus the remaining quarters. The primary outcome was operative morbidity as measured by Clavien-Dindo grade, a classification system of surgical complications. Secondary outcomes included mortality, operative blood loss, pancreatic fistula formation, delayed gastric emptying, intraabdominal abscess, anastomotic leak, reoperation, and other variables of interest.Results: From January 2003 to September 2015, 472 patients underwent PD by a single academic surgeon. Overall, 77.1% of PDs were performed for malignancy. The number of patients did not significantly vary by month or by quarter. The incidence of major morbidity (Clavien-Dindo grade ≥ III) in patients who had a PD was 12.2% in July and 17.5% in all other months (P = 0.79). The rate of pancreatic fistula, intraabdominal abscess, reoperation, readmission, and mortality did not differ significantly by month or by quarter (P > 0.05 for all).Conclusions: The current study does not find any correlation between time of year and operative morbidity or mortality, suggesting that PD can be safely performed irrespective of timing. [ABSTRACT FROM AUTHOR]

Background: Pancreatic neuroendocrine tumors (PNETs) are a heterogeneous group of islet cell-derived neoplasms with a propensity toward hormone production. Among PNETs, proinsulin-secreting tumors (proinsulinomas) are exceedingly rare. The objective of this study is to collect and summarize the existing literature to provide a comprehensive evaluation of this uncommon disease.Methods: A systematic review was performed to characterize the clinicopathologic features of proinsulinoma. Using the electronic biomedical databases PubMed, Ovid Medline, and Embase, 316 publications were screened for relevance of which 14 were selected. We also present two patients with proinsulinoma treated at Yale New Haven Hospital.Results: Of the 16 patients included in the study, the mean age was 56.8 and there was a 2:1 female predominance. The majority of patients presented with symptomatic hypoglycemia with normal or low insulin levels. Median tumor diameter was 1.2 cm and 80% were located in the body and tail of the pancreas. Following resection, most patients had normalization of hormonal levels without recurrence (75%; 12/16).Conclusion: Proinsulinomas are rare pancreatic neuroendocrine tumors that have the potential to cause hypoglycemia. While insulinomas and proinsulin-secreting tumors have many physiologic parallels, these cases illustrate several key distinctions in their diagnosis and management. [ABSTRACT FROM AUTHOR]

The purpose of this article is to discuss the challenges and opportunities for integrating archaeological information in landscape-scale conservation design while aligning archaeological practice with design and planning focused on cultural resources. Targeting this opportunity begins with statewide archaeological databases. Here, we compare the structure and content of Pennsylvania's and Florida's statewide archaeological databases, identifying opportunities for leveraging these data in landscape conservation design and planning. The research discussed here was part of a broader project, which was working through the lens of Landscape Conservation Cooperatives in order to develop processes for integrating broadly conceived cultural resources with natural resources as part of multistate or regional landscape conservation design efforts. Landscape Conservation Cooperatives offer new ways to think about archaeological information in practice and potentially new ways for archaeology to contribute to design and planning. Statewide archaeological databases, in particular, offer transformative potential for integrating cultural resource priorities in landscape conservation design. Targeted coordination across state boundaries along with the development of accessible derivative databases are two priorities to advance their utility. [ABSTRACT FROM AUTHOR]

We conducted unmanned aerial vehicle lidar missions in the Maya Lowlands between June 2017 and June 2018 to develop appropriate methods, procedures, and standards for drone lidar surveys of ancient Maya settlements and landscapes. Three site locations were tested within upper Usumacinta River region using Phoenix Lidar Systems: Piedras Negras, Guatemala, was tested in 2017, and Budsilha and El Infiernito, both in Mexico, were tested in 2018. These sites represent a range of natural and cultural contexts, which make them ideal to evaluate the usefulness of the technology in the field. Results from standard digital elevation and surface models demonstrate the utility of deploying drone lidar in the Maya Lowlands and throughout Latin America. Drone survey can be used to target and efficiently document ancient landscapes and settlement. Such an approach is adaptive to fieldwork and is cost effective but still requires planning and thoughtful evaluation of samples. Future studies will test and evaluate the methods and techniques for filtering and processing these data. [ABSTRACT FROM AUTHOR]

• The Gini index is used to measure differentiation in house size as a proxy to interpret inequality across a large environmental lidar dataset that documented a palimpsest of Maya archaeological settlement and landscapes. • We identify consistent patterns and Gini coefficients across the Maya lowlands, with notably lower values in peripheral areas, including coastal zones and the Western lowlands. • Despite the narrow lidar transects, the results of this study align with regional and site-based approaches across the Maya area. The emergence and expansion of inequality have been topics of household archaeology for decades. Traditionally, this question has been informed by ethnographic, ethnohistoric and/or comparative studies. Within sites and regions, comparative physical, spatial, and architectural studies of households offer an important baseline of information about status, wealth, and well-being, especially in the Maya lowlands where households are accessible in the archaeological record. Between sites, more research is necessary to assess how these physical measurements of household remains compare. This paper investigates the intersection of landscape, household, and community based on a multi-scalar analysis of households using the Gini index across southeastern Mexico, in the context of a broader study of land use, land management, and settlement patterns. Notably, this paper represents a region-wide analysis of nearly continuous LiDAR data within and outside of previously documented prehispanic Maya settlements. While we conclude that the Gini index is useful for establishing a comparative understanding of settlement, we also recognize that the index is a starting point to identify other ways to study how household to community-level social and economic variability intersects with diverse ecological patterns. Highlighting the opportunities and limitations with applying measures like the Gini index across culturally, temporally, and geographically heterogeneous areas, we illustrate how systematic studies of settlement can be coupled to broader studies of landscape archaeology to interpret changing patterns of land management and settlement across the Maya lowlands. [ABSTRACT FROM AUTHOR]

Despite recent comprehensive genetic analyses, molecular evidence for a pathophysiological continuum linking benign adrenocortical adenoma (ACA) and highly aggressive adrenocortical carcinoma (ACC) is still elusive. Using human tumor samples and the established ACC cell line SW-13, this study investigated potential regulatory roles for FOXO transcription factors, in modulating adrenocortical tumorigenesis. Adrenocortical tumor specimens (20 ACAs, 10 ACCs, and 9 normal adrenal tissue samples) obtained from 30 patients were analyzed for ubiquitously expressed FOXO transcription factors, FOXO1 and FOXO3 using qRT-PCR and immunohistochemistry. The SW-13 ACC cells were used to study the phenotypic effects of FOXO regulation in vitro. While FOXO3 expression remained unchanged in ACCs, FOXO1 expression was found to be significantly downregulated in 19/20 ACAs and 9/10 ACCs (p < 0.0001 and p < 0.05, respectively), suggesting a global role for FOXO1 suppression in promoting and maintaining adrenocortical dedifferentiation. Silencing of FOXO1 in SW-13 cells resulted in significant loss of viability (p < 0.001) mediated by apoptosis as determined by quantitative Annexin V immunofluorescence analysis (p < 0.01). FOXO1 silencing also augmented the migratory behavior of SW-13 cells (p < 0.0001), suggesting distinct roles for FOXO1 in promoting viability and controlled motility of adrenocortical cells. [ABSTRACT FROM AUTHOR]

In 1966 University of Pennsylvania archaeologists discovered impressive earthworks near the Classic Maya center of Tikal, Guatemala. They were provisionally interpreted as part of a vast "emic" defensive and boundary system that defined the political capital and the agricultural core of the Tikal polity around A.D. 400-550. These conclusions have heavily influenced conceptions of Classic Maya warfare, urbanism, polity, settlement, demography, and subsistence for 40 years, despite the fact that very little research was ever done on the earthworks. Three seasons of mapping and excavation in 2003-2006 support some of the conventional interpretations, but call others into question. That the earthworks were ever a functional defensive system seems doubtful. The new fieldwork has also yielded a wealth of new data about settlement distributions, household remains, soils, vegetation, and land use at Tikal. [ABSTRACT FROM AUTHOR]

Airborne laser scanning has proven useful for rapid and extensive documentation of historic cultural landscapes after years of applications mapping natural landscapes and the built environment. The recent integration of unoccupied aerial vehicles (UAVs) with LiDAR systems is potentially transformative and offers complementary data for mapping targeted areas with high precision and systematic study of coupled natural and human systems. We report the results of data capture, analysis, and processing of UAV LiDAR data collected in the Maya Lowlands of Chiapas, Mexico in 2019 for a comparative landscape study. Six areas of archaeological settlement and long-term land-use reflecting a diversity of environments, land cover, and archaeological features were studied. These missions were characterized by areas that were variably forested, rugged, or flat, and included pre-Hispanic settlements and agrarian landscapes. Our study confirms that UAV LiDAR systems have great potential for broader application in high-precision archaeological mapping applications. We also conclude that these studies offer an important opportunity for multi-disciplinary collaboration. UAV LiDAR offers high-precision information that is not only useful for mapping archaeological features, but also provides critical information about long-term land use and landscape change in the context of archaeological resources. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Pregnancy, primary aldosteronism, and adrenal CTNNB1 mutations" by A. D. E. Teo and colleagues in the October 8, 2015 issue.

Background: Altered expression of Solute Carrier Family 12 Member 7 (SLC12A7) is implicated to promote malignant behavior in multiple cancer types through an incompletely understood mechanism. Recent studies have shown recurrent gene amplifications and overexpression of SLC12A7 in adrenocortical carcinoma (ACC). The potential mechanistic effect(s) of SLC12A7 amplifications in portending an aggressive behavior in ACC has not been previously studied and is investigated here using two established ACC cell lines, SW-13 and NCI-H295R. Methods: SW-13 cells, which express negligible amounts of SLC12A7, were enforced to express SLC12A7 constitutively, while RNAi gene silencing was performed in NCI-H295R cells, which have robust endogenous expression of SLC12A7. In vitro studies tested the outcomes of experimental alterations in SLC12A7 expression on malignant characteristics, including cell viability, growth, colony formation potential, motility, invasive capacity, adhesion and detachment kinetics, and cell membrane organization. Further, potential alterations in transcription regulation downstream to induced SLC12A7 overexpression was explored using targeted transcription factor expression arrays. Results: Enforced SLC12A7 overexpression in SW-13 cells robustly promoted motility and invasive characteristics (p < 0.05) without significantly altering cell viability, growth, or colony formation potential. SLC12A7 overexpression also significantly increased rates of cellular attachment and detachment turnover (p < 0.05), potentially propelled by increased filopodia formation and/or Ezrin interaction. In contrast, RNAi gene silencing of SLC12A7 stymied cell attachment strength as well as migration and invasion capacity in NCI-H295R cells. Transcription factor expression analysis identified multiple signally pathways potentially affected by SLC12A7 overexpression, including osmotic stress, bone morphogenetic protein, and Hippo signaling pathways. Conclusions: Amplification of SLC12A7 observed in ACCs is shown here, in vitro, to exacerbate the malignant behavior of ACC cells by promoting invasive capacities, possibly mediated by alterations in multiple signaling pathways, including the osmotic stress pathway. [ABSTRACT FROM AUTHOR]

Diabetes is a chronic systemic disease that affects nearly one in eight adults worldwide. Ocular complications, such as cataract, can lead to significant visual impairment. Among the worldwide population, cataract is the leading cause of blindness, and patients with diabetes have an increased incidence of cataracts which mature earlier compared to the rest of the population. Cataract surgery is a common and safe procedure, but can be associated with vision-threatening complications in the diabetic population, such as diabetic macular edema, postoperative macular edema, diabetic retinopathy progression, and posterior capsular opacification. This article is a brief review of diabetic cataract and complications associated with cataract extraction in this population of patients. [ABSTRACT FROM AUTHOR]

Background: Dysregulated WNT signaling dominates adrenocortical malignancies. This study investigates whether silencing of the WNT negative regulator DKK3 (Dickkopf-related protein 3), an implicated adrenocortical differentiation marker and an established tumor suppressor in multiple cancers, allows dedifferentiation of the adrenal cortex.Methods: We analyzed the expression and regulation of DKK3 in human adrenocortical carcinoma (ACC) by qRT-PCR, immunofluorescence, promoter methylation assay, and copy number analysis. We also conducted functional studies on ACC cell lines, NCI-H295R and SW-13, using siRNAs and enforced DKK3 expression to test DKK3's role in blocking dedifferentiation of adrenal cortex.Results: While robust expression was observed in normal adrenal cortex, DKK3 was down-regulated in the majority (>75%) of adrenocortical carcinomas (ACC) tested. Both genetic (gene copy loss) and epigenetic (promoter methylation) events were found to play significant roles in DKK3 down-regulation in ACCs. While NCI-H295R cells harboring β-catenin activating mutations failed to respond to DKK3 silencing, SW-13 cells showed increased motility and reduced clonal growth. Conversely, exogenously added DKK3 also increased motility of SW-13 cells without influencing their growth. Enforced over-expression of DKK3 in SW-13 cells resulted in slower cell growth by an extension of G1 phase, promoted survival of microcolonies, and resulted in significant impairment of migratory and invasive behaviors, largely attributable to modified cell adhesions and adhesion kinetics. DKK3-over-expressing cells also showed increased expression of Forkhead Box Protein O1 (FOXO1) transcription factor, RNAi silencing of which partially restored the migratory proficiency of cells without interfering with their viability.Conclusions: DKK3 suppression observed in ACCs and the effects of manipulation of DKK3 expression in ACC cell lines suggest a FOXO1-mediated differentiation-promoting role for DKK3 in the adrenal cortex, silencing of which may allow adrenocortical dedifferentiation and malignancy. [ABSTRACT FROM AUTHOR]

White-nose syndrome (WNS) is an emerging infectious disease devastating hibernating North American bat populations that is caused by the psychrophilic fungus Geomyces destructans. Previous histopathological analysis demonstrated little evidence of inflammatory responses in infected bats, however few studies have compared other aspects of immune function between WNS-affected and unaffected bats. We collected bats from confirmed WNS-affected and unaffected sites during the winter of 2008–2009 and compared estimates of their circulating levels of total leukocytes, total immunoglobulins, cytokines and total antioxidants. Bats from affected and unaffected sites did not differ in their total circulating immunoglobulin levels, but significantly higher leukocyte counts were observed in bats from affected sites and particularly in affected bats with elevated body temperatures (above 20°C). Bats from WNS-affected sites exhibited significantly lower antioxidant activity and levels of interleukin-4 (IL-4), a cytokine that induces T cell differentiation. Within affected sites only, bats exhibiting visible fungal infections had significantly lower antioxidant activity and levels of IL-4 compared to bats without visible fungal infections. Overall, bats hibernating in WNS-affected sites showed immunological changes that may be evident of attempted defense against G. destructans. Observed changes, specifically elevated circulating leukocytes, may also be related to the documented changes in thermoregulatory behaviors of affected bats (i.e. increased frequencies in arousal from torpor). Alterations in immune function may reflect expensive energetic costs associated with these processes and intrinsic qualities of the immunocapability of hibernating bats to clear fungal infections. Additionally, lowered antioxidant activity indicates a possible imbalance in the pro- versus antioxidant system, may reflect oxidative tissue damage, and should be investigated as a contributor to WNS-associated morbidity and mortality. [ABSTRACT FROM AUTHOR]

White-nose syndrome (WNS) is the most devastating condition ever reported for hibernating bats, causing widespread mortality in the northeastern United States. The syndrome is characterized by cutaneous lesions caused by a recently identified psychrophilic and keratinophylic fungus (Geomyces destructans), depleted fat reserves, atypical behavior, and damage to wings; however, the proximate cause of mortality is still uncertain. To assess relative levels of immunocompetence in bats hibernating in WNS-affected sites compared with levels in unaffected bats, we describe blood plasma complement protein activity in hibernating little brown myotis (Myotis lucifugus) based on microbicidal competence assays using Escherichia coli, Staphylococcus aureus and Candida albicans. Blood plasma from bats collected during mid-hibernation at WNS-affected sites had higher bactericidal ability against E. coli and S. aureus, but lower fungicidal ability against C. albicans when compared with blood plasma from bats collected at unaffected sites. Within affected sites during mid-hibernation, we observed no difference in microbicidal ability between bats displaying obvious fungal infections compared to those without. Bactericidal ability against E. coli decreased significantly as hibernation progressed in bats collected from an affected site. Bactericidal ability against E. coli and fungicidal ability against C. albicans were positively correlated with body mass index (BMI) during late hibernation. We also compared complement activity against the three microbes within individuals and found that the ability of blood plasma from hibernating M. lucifugus to lyse microbial cells differed as follows: E. coli>S. aureus>C. albicans. Overall, bats affected by WNS experience both relatively elevated and reduced innate immune responses depending on the microbe tested, although the cause of observed immunological changes remains unknown. Additionally, considerable trade-offs may exist between energy conservation and immunological responses. Relationships between immune activity and torpor, including associated energy expenditure, are likely critical components in the development of WNS. [ABSTRACT FROM AUTHOR]

Abstract: Soil science methodologies often enrich archaeological reconstructions. In the Maya Lowlands of Mesoamerica, stable carbon (C) isotope ratio (δ13C) analysis of soil organic matter (SOM) from profiles near ancient archaeological sites has been used to interpret the vegetative histories related to ancient maize agriculture. Due to distinct photosynthetic processes, the decomposed organic matter from the cultivation of maize can be distinguished from SOM derived from native forest detritus. The recalcitrant nature of humic substances allows for this distinction to be preserved through time. This study evaluates SOM δ13C from 98 soil profiles near Tikal, Guatemala to identify areas of ancient Maya agriculture and the staple crops used. Ancillary physical and chemical properties of the soil profiles were examined to facilitate and to supplement the interpretation of the isotope data. Most of the soils analyzed in this study are shallow Haprendolls with limited C isotopic evidence of prehistoric vegetation changes. The deeper, well-developed Argiudolls and Hapludolls contained strong evidence of vegetation changes associated with ancient maize agriculture. Areas with strong δ13C signatures of ancient C4 vegetation corresponded with foot- and toeslope locations, high clay content and low phosphorus (P) levels. The shallow backslope soils lacked significant evidence of ancient agriculture. The connections between profile location, settlement, isotope data, and P levels enable the identification of both agriculture production zones and enhanced understanding of stable C isotope dynamics in soils within the unique physiographic and archaeological surroundings of the Maya Lowlands. [Copyright &y& Elsevier]

Purpose: To evaluate optical coherence tomography (OCT) thickness of the macula in people with diabetes but minimal or no retinopathy and to compare these findings with published normative data in the literature from subjects reported to have no retinal disease.Design: Cross-sectional study.Methods: In a multicenter community- and university-based practices setting, 97 subjects with diabetes with no or minimal diabetic retinopathy and no central retinal thickening on clinical examination and a center point thickness of 225 microm or less on OCT (Stratus OCT; Carl Zeiss Meditec, Dublin, California, USA) were recruited. Electronic Early Treatment of Diabetic Retinopathy Study best-corrected visual acuity, seven-field stereoscopic color fundus photographs, and Stratus OCT fast macular scan were noted. Main outcome measures were central subfield (CSF) thickness measured on Stratus OCT.Results: On average, CSF thickness was 201 +/- 22 microm. CSF thickness was significantly greater in retinas from men than retinas from women (mean +/- standard deviation, 209 +/- 18 microm vs 194 +/- 23 microm; P < .001). After adjusting for gender, no additional factors were found to be associated significantly with CSF thickness (P > .10).Conclusions: CSF thicknesses on Stratus OCT in people with diabetes and minimal or no retinopathy are similar to thicknesses reported from a normative database of people without diabetes. CSF thickness is greater in men than in women, consistent with many, but not all, previous reports. Studies involving comparisons of retinal thickness with expected norms should consider different mean values for women and men. [ABSTRACT FROM AUTHOR]

We present results from the archaeological analysis of 331 km2 of high-resolution airborne lidar data collected in the Upper Usumacinta River basin of Mexico and Guatemala. Multiple visualizations of the DEM and multi-spectral data from four lidar transects crossing the Classic period (AD 350–900) Maya kingdoms centered on the sites of Piedras Negras, La Mar, and Lacanja Tzeltal permitted the identification of ancient settlement and associated features of agricultural infrastructure. HDBSCAN (hierarchical density-based clustering of applications with noise) cluster analysis was applied to the distribution of ancient structures to define urban, peri-urban, sub-urban, and rural settlement zones. Interpretations of these remotely sensed data are informed by decades of ground-based archaeological survey and excavations, as well as a rich historical record drawn from inscribed stone monuments. Our results demonstrate that these neighboring kingdoms in three adjacent valleys exhibit divergent patterns of structure clustering and low-density urbanism, distributions of agricultural infrastructure, and economic practices during the Classic period. Beyond meeting basic subsistence needs, agricultural production in multiple areas permitted surpluses likely for the purposes of tribute, taxation, and marketing. More broadly, this research highlights the strengths of HDBSCAN to the archaeological study of settlement distributions when compared to more commonly applied methods of density-based cluster analysis. [ABSTRACT FROM AUTHOR]