Urinary Plasminogen as a Marker of Disease Progression in Human Glomerular Disease.

RATIONALE & OBJECTIVE: Glomerular disorders have a highly variable clinical course, and biomarkers that reflect the molecular mechanisms underlying their progression are needed. Based on our previous work identifying plasminogen as a direct cause of podocyte injury, we designed this study to test the association between urine plasmin(ogen) (ie, plasmin and its precursor plasminogen) and end-stage kidney disease (ESKD). STUDY DESIGN: Multicenter cohort study. SETTING & PARTICIPANTS: 1,010 patients enrolled in the CureGN Cohort with biopsy-proven glomerular disease (focal segmental glomerulosclerosis, membranous nephropathy, and immunoglobulin A nephropathy). PREDICTORS: The main predictor was urine plasmin(ogen) at baseline. Levels were measured by an electrochemiluminescent immunoassay developed de novo. Traditional clinical and analytical characteristics were used for adjustment. The ratio of urine plasmin(ogen)/expected plasmin(ogen) was evaluated as a predictor in a separate model. OUTCOME: Progression to ESKD. ANALYTICAL APPROACH: Cox regression was used to examine the association between urinary plasmin(ogen) and time to ESKD. Urinary markers were log2 transformed to approximate normal distribution and normalized to urinary creatinine (Log2uPlasminogen/cr, Log2 urinary protein/cr [UPCR]). Expected plasmin(ogen) was calculated by multiple linear regression. RESULTS: Adjusted Log2uPlasminogen/cr was significantly associated with ESKD (HR per doubling Log2 uPlasminogen/cr 1.31 [95% CI, 1.22-1.40], P<0.001). Comparison of the predictive performance of the models including Log2 uPlasminogen/cr, Log2 UPCR, or both markers showed the plasmin(ogen) model superiority. The ratio of measured/expected urine plasmin(ogen) was independently associated with ESKD: HR, 0.41 (95% CI, 0.22-0.77) if ratio<0.8 and HR 2.42 (95% CI, 1.54-3.78) if ratio>1.1 (compared with ratio between 0.8 and 1.1). LIMITATIONS: Single plasmin(ogen) determination does not allow for the study of changes over time. The use of a cohort of mostly white patients and the restriction to patients with 3 glomerular disorders limits the external validity of our analysis. CONCLUSIONS: Urinary plasmin(ogen) and the ratio of measured/expected plasmin(ogen) are independently associated with ESKD in a cohort of patients with glomerular disease. Taken together with our previous experimental findings, urinary plasmin(ogen) could be a useful biomarker in prognostic decision making and a target for the development of novel therapies in patients with proteinuria and glomerular disease. PLAIN-LANGUAGE SUMMARY: Glomerular diseases are an important cause of morbidity and mortality in patients of all ages. Knowing the individual risk of progression to dialysis or transplantation would help to plan the follow-up and treatment of these patients. Our work studies the usefulness of urinary plasminogen as a marker of progression in this context, since previous studies indicate that plasminogen may be involved in the mechanisms responsible for the progression of these disorders. Our work in a sample of 1,010 patients with glomerular disease demonstrates that urinary plasminogen (as well as the ratio of measured to expected plasminogen) is associated with the risk of progression to end-stage kidney disease. Urine plasminogen exhibited good performance and, if further validated, could enable risk stratification for timely interventions in patients with proteinuria and glomerular disease.

Lessons from COP15 on effective scientific engagement in biodiversity policy processes.

The Kunming-Montreal Global Biodiversity Framework was adopted by parties to the Convention on Biological Diversity in December 2022. The aftermath of these negotiations provides an opportunity to draw lessons as to how ecological and evolutionary science can more effectively inform policy. We examined key challenges that limit effective engagement by scientists in the biodiversity policy process, drawing parallels with analogous challenges within global climate negotiations. Biodiversity is multifaceted, yet represents only one framing for nature's contributions to people, complicating the nexus between evidence and values in development of the framework's targets. Processes generating biodiversity and driving its loss are multiscalar, challenging development of an evidence base for globally standardized targets. We illustrated these challenges by contrasting development of 2 key elements of the framework. The genetic diversity element of the framework's target 4 is directly related to the framework's primary goals, but its complexity required development of novel engagement skills. The target for protected areas was easily communicated but more indirectly related to biodiversity outcomes; evidence from ecological and social science was essential to communicating the context and limitations of this relationship. Scientists can strengthen the effectiveness of global agreements and address challenges arising from complexity, scaling, capacity limitations, and the interplay of science and values, if they can prioritize communication, consensus-building, and networking skills and engage throughout the process, from development of an evidence base to implementation.

Lecciones de la COP15 sobre la participación científica efectiva en los procesos políticos de biodiversidad Resumen El Marco Global de la Biodiversidad de Kunming­Montreal lo adoptaron los participantes de la Convención sobre la Diversidad Biológica en diciembre 2022. Las consecuencias de estas negociaciones proporcionan una oportunidad para tomar lecciones de cómo la ciencia evolutiva y ecológica puede orientar de mejor manera a las políticas. Examinamos los retos clave que limitan la participación efectiva de los científicos en el proceso de políticas de la biodiversidad, estableciendo paralelismos con los retos análogos en las negociaciones climáticas mundiales. La biodiversidad es multifacética y aun así representa sólo un marco para las contribuciones que tiene la naturaleza para las personas, lo que complica el nexo entre la evidencia y los valores en el desarrollo de los objetivos del marco. Los procesos que generan la biodiversidad y causan su pérdida son multiescalares, lo que representa un reto para el desarrollo de una base de evidencias para tener objetivos mundiales estandarizados. Ilustramos estos retos con el contraste del desarrollo de dos elementos clave del marco. El elemento de la diversidad genética en el objetivo 4 del marco está relacionado directamente con los objetivos principales del marco, pero su complejidad requiere el desarrollo de habilidades novedosas de participación. El objetivo para las áreas protegidas se comunicó con facilidad, pero estuvo relacionado de forma más indirecta con los resultados de biodiversidad; la evidencia de las ciencias sociales y ecológicas fue esencial para comunicar el contexto y las limitaciones de esta relación. Los científicos pueden fortalecer la efectividad de los acuerdos globales y abordar los retos que surgen de la complejidad, el escalamiento, las limitaciones en la capacidad y la interacción de la ciencia y los valores, si pueden priorizar la comunicación, la llegada a consensos y el conocimiento de redes y participan durante el proceso, a partir del desarrollo de una evidencia base hasta la implementación.

Maximizing the effectiveness of national commitments to protected area expansion for conserving biodiversity and ecosystem carbon under climate change.

Global commitments to protected area expansion should prioritize opportunities to protect climate refugia and ecosystems which store high levels of irrecoverable carbon, as key components of an effective response to biodiversity loss and climate change. The United States and Canada are responsible for one-sixth of global greenhouse gas emissions but hold extensive natural ecosystems that store globally significant above- and below-ground carbon. Canada has initiated a process of protected area network expansion in concert with efforts at reconciliation with Indigenous Peoples, and acknowledged nature-based solutions as a key aspect of climate change mitigation. The US, although not a party to global biodiversity conventions, has recently committed to protecting 30% of its extent by 2030 and achieving the UNFCCC Paris Agreement's mitigation targets. The opportunities afforded by these dual biodiversity conservation and climate commitments require coordinated national and regional policies to ensure that new protected areas maximize biodiversity-focused adaptation and nature-based mitigation opportunities. We address how global commitments can best inform national policy initiatives which build on existing agency mandates for regional planning and species conservation. Previous analyses of global conservation priorities under climate change have been tenuously linked to policy contexts of individual nations and have lacked information on refugia due to limitations of globally available datasets. Comparison and synthesis of predictions from a range of recently developed refugia metrics allow such data to inform planning despite substantial uncertainty arising from contrasting model assumptions and inputs. A case study for endangered species planning for old-forest-associated species in the US Pacific Northwest demonstrates how regional planning can be nested hierarchically within national biodiversity-focused adaptation and nature-based mitigation strategies which integrate refugia, connectivity, and ecosystem carbon metrics to holistically evaluate the role of different land designations and where carbon mitigation and protection of biodiversity's resilience to climate change can be aligned.

The Hippo pathway regulator KIBRA promotes podocyte injury by inhibiting YAP signaling and disrupting actin cytoskeletal dynamics.

Kidney podocytes represent a key constituent of the glomerular filtration barrier. Identifying the molecular mechanisms of podocyte injury and survival is important for better understanding and management of kidney diseases. KIBRA (kidney brain protein), an upstream regulator of the Hippo signaling pathway encoded by the Wwc1 gene, shares the pro-injury properties of its putative binding partner dendrin and antagonizes the pro-survival signaling of the downstream Hippo pathway effector YAP (Yes-associated protein) in Drosophila and MCF10A cells. We recently identified YAP as an essential component of the glomerular filtration barrier that promotes podocyte survival by inhibiting dendrin pro-apoptotic function. Despite these recent advances, the signaling pathways that mediate podocyte injury remain poorly understood. Here we tested the hypothesis that, similar to its role in other model systems, KIBRA promotes podocyte injury. We found increased expression of KIBRA and phosphorylated YAP protein in glomeruli of patients with biopsy-proven focal segmental glomerulosclerosis (FSGS). KIBRA/WWc1 overexpression in murine podocytes promoted LATS kinase phosphorylation, leading to subsequent YAP Ser-127 phosphorylation, YAP cytoplasmic sequestration, and reduction in YAP target gene expression. Functionally, KIBRA overexpression induced significant morphological changes in podocytes, including disruption of the actin cytoskeletal architecture and reduction of focal adhesion size and number, all of which were rescued by subsequent YAP overexpression. Conversely, constitutive KIBRA knockout mice displayed reduced phosphorylated YAP and increased YAP expression at baseline. These mice were protected from acute podocyte foot process effacement following protamine sulfate perfusion. KIBRA knockdown podocytes were also protected against protamine-induced injury. These findings suggest an important role for KIBRA in the pathogenesis of podocyte injury and the progression of proteinuric kidney disease.

Hippo signaling in the kidney: the good and the bad.

The Hippo signaling pathway is an evolutionarily conserved kinase cascade, playing multiple roles in embryonic development that controls organ size, cell proliferation, and apoptosis. At the center of this network lie the Hippo kinase target and downstream pathway effector Yes-associated protein (YAP) and its paralog TAZ. In its phosphorylated form, cytoplasmic YAP is sequestered in an inactive state. When it is dephosphorylated, YAP, a potent oncogene, is activated and relocates to the nucleus to interact with a number of transcription factors and signaling regulators that promote cell growth, differentiation, and survival. The identification of YAP activation in human cancers has made it an attractive target for chemotherapeutic drug development. Little is known to date about the function of the Hippo pathway in the kidney, but that is rapidly changing. Recent studies have shed light on the role of Hippo-YAP signaling in glomerular and lower urinary tract embryonic development, maintenance of podocyte homeostasis, the integrity of the glomerular filtration barrier, regulation of renal tubular cyst growth, renal epithelial injury in diabetes, and renal fibrogenesis. This review summarizes the current knowledge of the Hippo-YAP signaling axis in the kidney under normal and disease conditions.

The Depressed Frail Phenotype: The Clinical Manifestation of Increased Biological Aging.

Depression in later life is a severe public health problem, associated with higher rates of mortality, suicide, and dementia. Effectiveness of treatment is limited by the failure to deconstruct the heterogeneity of the illness and because diagnostic criteria, pathophysiological models, and treatment algorithms for depression are primarily based on studies of younger adults even though symptoms of the illness and physiology of the patient change with age. Thus, understanding how aging interacts with depressive illness may elucidate endophenotypes of late-life depression with different clinical manifestations and underlying mechanisms that can then be targeted with more personalized approaches to treatment. This paper proposes a model for the critical confluence between depression and frailty, a high-risk morbidity and mortality syndrome of later life. This model hypothesizes that characteristics of frailty in adults with late life depression represent the clinical manifestation of greater biological aging and their presence in the context of a depressive illness exposes elders to deleterious trajectories. Potential common biological substrates that may result in the manifestation of the depressed frail phenotype including mitochondrial functioning, dopaminergic neurotransmission, and inflammatory processes and implications for the assessment and treatment of adults with late-life depression are discussed. As society continues to live longer, the preservation of the quality of these added years becomes paramount, and the combined impact of depression and frailty on the preservation of this quality warrants the attention of clinical researchers and physicians.

The Negative Impact of Routine, Dietary Pattern, and Physical Activity on Obesity and Dysglycemia During the COVID-19 Pandemic.

The global coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak, has disrupted routines in education, work, exercise, and dining habits. To prevent viral spread, communal spaces including offices, schools, restaurants, and gyms have closed or drastically limited their capacity. Additionally, government-mandated lockdown orders have forced people to spend more time at home. Studies have shown that these COVID-19 restrictions have led to unhealthier eating patterns, increased sedentary behaviors, and decreased physical activity, leading to weight gain, dysglycemia, and increased metabolic risk. While strict social distancing measures have been necessary to curb the spread of the SARS-CoV-2 virus, people have been forced to adapt by altering their daily routines. Based on existing literature, a model is proposed for intentionally creating daily routines to ensure healthy habits, minimize weight gain, and prevent worsening dysglycemia.

Role of Finerenone in the Treatment of Diabetic Kidney Disease: Patient Selection and Clinical Perspectives.

Diabetes is the leading cause of chronic and end stage kidney disease globally. Despite recent advances in therapies for diabetic kidney disease (DKD), there remains a critical need for additional options to improve renal and cardiovascular outcomes. Mineralocorticoid overactivation contributes to inflammation and fibrosis which in turn leads to progression of DKD. Finerenone, a novel non-steroidal mineralocorticoid receptor antagonist, has shown promising cardiac and renoprotective benefits in DKD. The utility of finerenone in the real world will require appropriate patient selection and patient monitoring by clinicians.

COVAN Leading to ESKD Despite Minimal COVID Symptoms.

We report a case of dialysis dependence in a patient with COVID-19-associated nephropathy (COVAN) who had minimal respiratory manifestations. A 25-year-old man with a history of multiple sclerosis in remission presented with mild dyspnea due to COVID-19 pneumonia and was found to have rapidly worsening kidney function. He only required nasal cannula and was able to be weaned off within a few days. Despite having only mild respiratory disease, his kidney function worsened and urgent hemodialysis was started for hyperkalemia and uremic encephalopathy. Kidney biopsy demonstrated collapsing glomerulopathy due to COVID-19 with moderate interstitial fibrosis and tubular atrophy. His kidney function did not recover, and he unfortunately now has been dependent on hemodialysis for over 3 months. Multiple case reports have described COVAN causing dialysis dependence, but to our knowledge this is the first reported case of COVAN causing dialysis dependence in a patient with such mild respiratory disease. Currently the indications for intensive COVID-19 therapies are based on oxygen requirements. This case demonstrates that the oxygen requirement may not fully reflect the severity of COVID-19 and raises the question of whether these therapies should be considered in patients with COVAN.

Podocyte Foot Process Effacement Precedes Albuminuria and Glomerular Hypertrophy in CD2-Associated Protein Deficient Mice.

Background: Podocyte foot process effacement is a key histologic finding in proteinuric kidney disease. We previously showed that 3-week old CD2AP-deficient mice have significant proteinuria, glomerular hypertrophy and mesangial expansion. The goal of this study is to use morphometry to establish the temporal sequence of podocyte foot process effacement, glomerular volume expansion and albuminuria in Cd2ap -/- mice by measuring these parameters at the 2-week time point. Methods: Wild-type mice age 14 ± 1 days with the Cd2ap gene (WT, N = 5) and mice deficient for Cd2ap (Cd2ap KO, N = 5) were generated. Kidneys were harvested and fixed in 2.5% glutaraldehyde and processed for examination by light and electron microscopy. An average of 415.2 (range 268-716) grid points were counted for all the glomeruli, and quantification of glomerular volume from each kidney. Urine was collected the day prior to sacrifice for urine albumin-to-creatinine ratio (ACR) measurements. Results: There was no difference in albuminuria [median (range) mg/g] between WT [212.2 (177.6-388.4) mg/g] vs. Cd2ap KO mice [203.3 (164.7-910.2) mg/g], P = 0.89; or glomerular volume 68,307[10,931] vs. 66,844[13,022] µm3, p = 0.92. The volume densities of glomerular components of the podocyte, capillary lumen and mesangium were not different for the two groups, P = 0.14, 0.14 and 0.17 respectively. However, foot process width was increased in Cd2ap KO 1128[286] vs. WT [374 ± 42] nm, P = 0.02. Conclusion: Here we show that while 2-week old WT and Cd2ap KO mice have similar levels of albuminuria, glomerular and mesangial volume, Cd2ap KO mice have more extensive podocyte foot process effacement. The data suggests that podocyte injury is the initiating event leading to mesangial expansion and albuminuria in this model.

GSK2256294 Decreases sEH (Soluble Epoxide Hydrolase) Activity in Plasma, Muscle, and Adipose and Reduces F2-Isoprostanes but Does Not Alter Insulin Sensitivity in Humans.

[Figure: see text].

Implications of Zoonoses From Hunting and Use of Wildlife in North American Arctic and Boreal Biomes: Pandemic Potential, Monitoring, and Mitigation.

The COVID-19 pandemic has re-focused attention on mechanisms that lead to zoonotic disease spillover and spread. Commercial wildlife trade, and associated markets, are recognized mechanisms for zoonotic disease emergence, resulting in a growing global conversation around reducing human disease risks from spillover associated with hunting, trade, and consumption of wild animals. These discussions are especially relevant to people who rely on harvesting wildlife to meet nutritional, and cultural needs, including those in Arctic and boreal regions. Global policies around wildlife use and trade can impact food sovereignty and security, especially of Indigenous Peoples. We reviewed known zoonotic pathogens and current risks of transmission from wildlife (including fish) to humans in North American Arctic and boreal biomes, and evaluated the epidemic and pandemic potential of these zoonoses. We discuss future concerns, and consider monitoring and mitigation measures in these changing socio-ecological systems. While multiple zoonotic pathogens circulate in these systems, risks to humans are mostly limited to individual illness or local community outbreaks. These regions are relatively remote, subject to very cold temperatures, have relatively low wildlife, domestic animal, and pathogen diversity, and in many cases low density, including of humans. Hence, favorable conditions for emergence of novel diseases or major amplification of a spillover event are currently not present. The greatest risk to northern communities from pathogens of pandemic potential is via introduction with humans visiting from other areas. However, Arctic and boreal ecosystems are undergoing rapid changes through climate warming, habitat encroachment, and development; all of which can change host and pathogen relationships, thereby affecting the probability of the emergence of new (and re-emergence of old) zoonoses. Indigenous leadership and engagement in disease monitoring, prevention and response, is vital from the outset, and would increase the success of such efforts, as well as ensure the protection of Indigenous rights as outlined in the United Nations Declaration on the Rights of Indigenous Peoples. Partnering with northern communities and including Indigenous Knowledge Systems would improve the timeliness, and likelihood, of detecting emerging zoonotic risks, and contextualize risk assessments to the unique human-wildlife relationships present in northern biomes.

Landscape ecology of eastern coyotes based on large-scale estimates of abundance.

Since their range expansion into eastern North America in the mid-1900s, coyotes (Canis latrans) have become the region's top predator. Although widespread across the region, coyote adaptation to eastern forests and use of the broader landscape are not well understood. We studied the distribution and abundance of coyotes by collecting coyote feces from 54 sites across a diversity of landscapes in and around the Adirondacks of northern New York. We then genotyped feces with microsatellites and found a close correlation between the number of detected individuals and the total number of scats at a site. We created habitat models predicting coyote abundance using multi-scale vegetation and landscape data and ranked them with an information-theoretic model selection approach. These models allow us to reject the hypothesis that eastern forests are unsuitable habitat for coyotes as their abundance was positively correlated with forest cover and negatively correlated with measures of rural non-forest landscapes. However, measures of vegetation structure turned out to be better predictors of coyote abundance than generalized "forest vs. open" classification. The best supported models included those measures indicative of disturbed forest, especially more open canopies found in logged forests, and included natural edge habitats along water courses. These forest types are more productive than mature forests and presumably host more prey for coyotes. A second model with only variables that could be mapped across the region highlighted the lower density of coyotes in areas with high human settlement, as well as positive relationships with variables such as snowfall and lakes that may relate to increased numbers and vulnerability of deer. The resulting map predicts coyote density to be highest along the southwestern edge of the Adirondack State Park, including Tug Hill, and lowest in the mature forests and more rural areas of the central and eastern Adirondacks. Together, these results support the need for a nuanced view of how eastern coyotes use forested habitats.

Sleep health disparity: the putative role of race, ethnicity and socioeconomic status.

Sleep plays a pivotal role in both physical and mental health. Sleep quality can be affected by many socio demographic factors, such as race and/or ethnicity, as well as socio economic status (SES). Chronic sleep deprivation is associated with unhealthy behaviors such as alcohol abuse and also places individuals at risk for chronic diseases including obesity, cardiovasculardisease (CVD), depression, and/or anxiety. This review explores the common socio demographic factors and SES that can lead to sleep disturbances. Among these factors are shift work, poor dietary habits, smoking and alcohol abuse. Such factors need to be considered by health care providers in the clinical assessment and management plans of patients with sleep disorders.

The exceptional value of intact forest ecosystems.

As the terrestrial human footprint continues to expand, the amount of native forest that is free from significant damaging human activities is in precipitous decline. There is emerging evidence that the remaining intact forest supports an exceptional confluence of globally significant environmental values relative to degraded forests, including imperilled biodiversity, carbon sequestration and storage, water provision, indigenous culture and the maintenance of human health. Here we argue that maintaining and, where possible, restoring the integrity of dwindling intact forests is an urgent priority for current global efforts to halt the ongoing biodiversity crisis, slow rapid climate change and achieve sustainability goals. Retaining the integrity of intact forest ecosystems should be a central component of proactive global and national environmental strategies, alongside current efforts aimed at halting deforestation and promoting reforestation.

Differential Habitat Use or Intraguild Interactions: What Structures a Carnivore Community?

Differential habitat use and intraguild competition are both thought to be important drivers of animal population sizes and distributions. Habitat associations for individual species are well-established, and interactions between particular pairs of species have been highlighted in many focal studies. However, community-wide assessments of the relative strengths of these two factors have not been conducted. We built multi-scale habitat occupancy models for five carnivore taxa of New York's Adirondack landscape and assessed the relative performance of these models against ones in which co-occurrences of potentially competing carnivore species were also incorporated. Distribution models based on habitat performed well for all species. Black bear (Ursus americanus) and fisher (Martes pennanti) distribution was similar in that occupancy of both species was negatively associated with paved roads. However, black bears were also associated with larger forest fragments and fishers with smaller forest fragments. No models with habitat features were more supported than the null habitat model for raccoons (Procyon lotor). Martens (Martes americana) were most associated with increased terrain ruggedness and elevation. Weasel (Mustela spp.) occupancy increased with the cover of deciduous forest. For most species dyads habitat-only models were more supported than those models with potential competitors incorporated. The exception to this finding was for the smallest carnivore taxa (marten and weasel) where habitat plus coyote abundance models typically performed better than habitat-only models. Assessing this carnivore community as whole, we conclude that differential habitat use is more important than species interactions in maintaining the distribution and structure of this carnivore guild.

Influence of Timber Extraction Routes on Central African Small-Mammal Communities, Forest Structure, and Tree Diversity.

Despite increasing pressure to harvest timber from African tropical forests, the short- and long-term ecological effects of qualitative and quantitative variation in extraction practices rarely have been examined. At a site in the southwestern Central African Republic, we surveyed rodent and tree communities and vegetation structure in unlogged forest and along skid trails and secondary and primary access roads at 12 and 19 years after logging. The most important source of variation among transects was the type of logging road: primary and secondary access roads showed the greatest change and skid trails the least. An intercorrelated suite of changes occurred along the margins of the roads, including changes in rodent community composition, increases in rodent abundance and diversity, changes in the height distribution of rodent abundance, increases in understory foliage density, and decreases in sapling density and tree species richness. Ecological changes along the secondary roads were nearly as strong as those along primary roads, despite the fact that secondary roads had been abandoned immediately after logging, whereas primary roads had been traveled up to the time of the research. Continuing edge-induced effects along graded road margins at between 12 and 19 years after logging were indicated by differences in tree species composition, sapling and tree densities, and understory density. Our results support conclusions of increased disturbance to rainforest communities with increasingly destructive road construction techniques and suggest that canopy damage rather than stem damage is the most appropriate measure of logging damage. Although minimizing the length of access roads is important in reducing ecological effects, it should not be achieved at the expense of increased canopy damage. Rodent communities appear to be an easily measured indicator of these ecological changes and may be responsive to landscape-level changes in forest cover and degradation.

RESUMEN: A pesar de la creciente presión para cosechar la madera de los bosques tropicales africanos, los efectos ecológicos a corto y largo plazo de la variación cualitativa y cuantitativa de las prácticas de extracción rara vez han sido estudiados. En un sitio del sudoeste de la República Centroafricana, evaluamos las comunidades de roedores y de árboles y la estructura de la vegetación en bosques sin talar y a lo largo de senderos de arrastre y caminos de acceso secundarios y primarios en bosques 12 y 19 años posteriores a la tala. Los muestreos se llevaron a cabo en transectos de 280 m de largo. La fuente de variación más importante entre los transectos fue el tipo de camino de acceso: los caminos de acceso primarios y secundarios mostraron los cambios mayores y los senderos de arrastre los menores. Una serie de cambios intercorrelacionados ocurrieron a lo largo de los márgenes de los caminos, incluyendo cambios en la composición de las comunidades de roedores, incrementos en la abundancia y diversidad de roedores, cambios en la distribución a lo alto de la abundancia de roedores, incrementos en la densidad del follaje de sotobosque y disminuciones en la densidad de árboles jóvenes y en la riqueza de especies de árboles. Los cambios ecológicos a lo largo de los caminos secundarios fueron casi tan fuertes como aquéllos en los caminos primarios. Esto a pesar de que los caminos secundarios fueron abandonados inmediatamente después de la tala, mientras que los caminos primarios fueron utilizados hasta el momento de la investigación. Los efectos continuos inducidos por bordes a lo largo de los márgenes de los caminos evaluados 12 y 19 años después de la tala fueron indicados por las diferencias en la composición de especies de árboles, las densidades de árboles maduros y jóvenes, y la densidad del sotobosque. Nuestros resultados apoyan conclusiones de una mayor perturbación para las comunidades del bosque lluvioso a medida que las técnicas de construcción son más destructivas y sugieren que el daño al dosel, y no el daño a los troncos, es la medida más adecuada del daño de la tala. Aunque el minimizar la longitud de los caminos de acceso es importante en la reducción de efectos ecológicos, esto no se debería llevar a cabo a costa de un incremento en el daño al dosel. Las comunidades de roedores aparentan ser un indicador de estos cambios ecológicos fácil de medir y pueden ser sensibles a cambios en la cobertura y degradación forestal.

Styles of male social behavior and their endocrine correlates among high-ranking wild baboons.

We have previously studied the relationship between dominance rank and physiology among male olive baboons (Papio anubis) living freely in a national park in Africa. In stable hierarchies, such males have distinctive secretory profiles of glucocorticoids and of testosterone. We find that these endocrine features are not, in fact, purely markers of social dominance; instead, they are found only among dominant males with particular stylistic traits of social behavior. One intercorrelated stylistic cluster revolved around the intensity with which the male is involved in sexual consortships (e.g., frequency of copulation, of grooming, degree to which feeding is suppressed by being in consortship). Males most involved in such consortships had the lowest basal cortisol concentrations and smaller cortisol stress-responses. A second stylistic cluster revolved around the degree of social affiliation (e.g., rate of grooming and interacting positively with non-estrus females and infants). Males who were highly affiliated had low basal cortisol concentrations and an attenuated cortisol stress-response. A third cluster revolved around the degree to which males could distinguish between highly threatening interactions with rivals and neutral or mildly threatening ones. Males most adept at this had lower basal cortisol concentrations. These behavioral/endocrine clusters were independent of each other. This suggests that the same adaptive physiological feature (e.g., low basal cortisol concentrations) may arise from different and independent personality styles. © 1992 Wiley-Liss, Inc.

Styles of dominance and their endocrine correlates among wild olive baboons (Papio anubis).

We have studied the relationship between dominance rank and physiology among male olive baboons (Papio anubis) living freely in a national park in Africa. In stable hierarchies, dominant males consistently have lower basal concentrations than do subordinates of the adrenal glucocorticoid cortisol. Because of the known catabolic actions of glucocorticoids, dominant males may be less at risk for some of the pathogenic consequences of glucocorticoid overexposure. We find that low basal cortisol concentration is not, in fact, a marker of social dominance; instead, it is only found among dominant males with a certain style of dominance. Lower basal cortisol concentrations occurred among males with any of the following behaviors: the most marked ability to distinguish between threatening and merely neutral interactions with rivals and, if the former, the greatest likelihood of initiating a fight; the most skill at distinguishing between winning and losing a fight and, if the latter, the greatest likelihood of displacing aggression onto a third party. Collectively, these behaviors suggest high degrees of social skillfulness, control, and predictability over social contingencies, all recognized as psychological features that minimize the pathophysiological impact of stress. Dominant males lacking these behavioral features, in contrast, had as high cortisol concentrations as did subordinate males. Finally, low basal cortisol concentrations were also a feature of males with the longest tenures in the dominant cohort, suggesting that this endocrine dichotomy is meaningful in terms of life histories.