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1.
Curr Biol ; 34(8): 1780-1785.e4, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38614078

RESUMO

Researchers investigating the evolution of human aggression look to our closest living relatives, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes), as valuable sources of comparative data.1,2 Males in the two species exhibit contrasting patterns: male chimpanzees sexually coerce females3,4,5,6,7,8 and sometimes kill conspecifics,9,10,11,12 whereas male bonobos exhibit less sexual coercion13,14 and no reported killing.13 Among the various attempts to explain these species differences, the self-domestication hypothesis proposes negative fitness consequences of male aggression in bonobos.2,15,16 Nonetheless, the extent to which these species differ in overall rates of aggression remains unclear due to insufficiently comparable observation methods.17,18,19,20,21,22,23 We used 14 community-years of focal follow data-the gold standard for observational studies24-to compare rates of male aggression in 3 bonobo communities at the Kokolopori Bonobo Reserve, Democratic Republic of Congo, and 2 chimpanzee communities at Gombe National Park, Tanzania. As expected, given that females commonly outrank males, we found that bonobos exhibited lower rates of male-female aggression and higher rates of female-male aggression than chimpanzees. Surprisingly, we found higher rates of male-male aggression among bonobos than chimpanzees even when limiting analyses to contact aggression. In both species, more aggressive males obtained higher mating success. Although our findings indicate that the frequency of male-male aggression does not parallel species difference in its intensity, they support the view that contrary to male chimpanzees, whose reproductive success depends on strong coalitions, male bonobos have more individualistic reproductive strategies.25.


Assuntos
Agressão , Pan paniscus , Pan troglodytes , Animais , Pan paniscus/psicologia , Pan paniscus/fisiologia , Pan troglodytes/fisiologia , Pan troglodytes/psicologia , Masculino , República Democrática do Congo , Tanzânia , Feminino , Especificidade da Espécie , Comportamento Sexual Animal/fisiologia
2.
Elife ; 122023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38078902

RESUMO

Because of their close relationship with humans, non-human apes (chimpanzees, bonobos, gorillas, orangutans, and gibbons, including siamangs) are of great scientific interest. The goal of understanding their complex behavior would be greatly advanced by the ability to perform video-based pose tracking. Tracking, however, requires high-quality annotated datasets of ape photographs. Here we present OpenApePose, a new public dataset of 71,868 photographs, annotated with 16 body landmarks of six ape species in naturalistic contexts. We show that a standard deep net (HRNet-W48) trained on ape photos can reliably track out-of-sample ape photos better than networks trained on monkeys (specifically, the OpenMonkeyPose dataset) and on humans (COCO) can. This trained network can track apes almost as well as the other networks can track their respective taxa, and models trained without one of the six ape species can track the held-out species better than the monkey and human models can. Ultimately, the results of our analyses highlight the importance of large, specialized databases for animal tracking systems and confirm the utility of our new ape database.


All animals carry out a wide range of behaviors in everyday life, such as feeding and communicating with one another. Understanding the complex behavior of non-human apes such as chimpanzees, bonobos, gorillas, orangutans, and various gibbons is of great interest to scientists due to their close relationship with humans. Each behavior is made up of a string of poses that an animal makes with its body. To analyze them in a reliable and consistent way, scientists have developed automated pose estimation methods that determine the position of body parts from photographs and videos. While these systems require minimal external input to perform, they need to be trained on a large dataset of high-quality annotated images of the target animals to teach the system what to look for. So far, scientists have relied on systems trained on monkey and human images to analyze ape data. However, apes are particularly challenging to track because their body textures are uniform, and they have a large number of poses. Therefore, for the most accurate tracking of ape behaviors, a dedicated training dataset of annotated ape images is required. Desai et al. filled this gap by creating the "OpenApePose" dataset, which contains 71,868 photographs of apes from six species, annotated using 16 body landmarks. To test the dataset, the researchers trained an artificial intelligence network on separate monkey, human and ape datasets. The findings showed that the network is better at tracking apes when trained on ape images rather than those of monkeys or humans. It is also equally good at tracking apes as other monkey and human networks are at tracking their own species. This is contrary to optimistic expectations that monkey and human models could be generalized to apes. Training the network without images of one of the six ape species showed that it can still track the excluded species better than monkey and human models can. These experiments highlight the importance of species and family-specific datasets. OpenApePose is a valuable resource for researchers from various fields. It can aid tracking of animal behavior in the wild using large quantities of footage recorded by camera traps and drones. Artificial intelligence models trained on the OpenApePose dataset could also help scientists ­ such as neuroscientists ­ link movement with other types of data, including brain activity measurements, to gain deeper insights into behavior.


Assuntos
Hominidae , Animais , Gorilla gorilla , Pan troglodytes , Haplorrinos , Pan paniscus , Hylobates
3.
Updates Surg ; 75(7): 1991-1996, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37195549

RESUMO

Ventral hernias with large defects (≥ 2 cm) are managed with tension free mesh repair. The growing consensus that sublay (retrorectus) mesh repair is superior to onlay mesh repair due to fewer complications is based on literature dominated by retrospective studies from high and upper-middle income countries. There is thus a need of more prospective studies from various countries to resolve the controversy. The objective of this study was to compare the outcomes of onlay versus sublay mesh repair in the management of ventral hernias. Our single centre, prospective comparative study set in a low-middle income country comprised of 60 patients with a ventral hernia undergoing open surgical repair using either onlay technique (n = 30) or sublay technique (n = 30). Surgical site infections, seroma formation, recurrence were found in 3.33%, 6.67%, 0% patients in sublay repair group and in 16.67%, 20%, 6.67% patients in onlay repair group respectively. Mean duration of surgery, mean Visual Analogue Scale (VAS) score for chronic pain, mean duration of hospital stay were 46 min, 4.5, 8 days in onlay repair group and 61 min, 4.2, 6 days in sublay repair group respectively. Onlay repair group was associated with shorter duration of surgery. However, sublay repair was associated with lesser rates of surgical site infections, chronic pain and recurrence than onlay repair. Sublay mesh repair had better outcomes than onlay mesh repair for the management of ventral hernias, however superiority of any one technique could not be established.


Assuntos
Dor Crônica , Hérnia Ventral , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Telas Cirúrgicas , Dor Crônica/cirurgia , Hérnia Ventral/cirurgia , Herniorrafia/métodos , Recidiva
4.
Am J Primatol ; 84(11): e23430, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36093564

RESUMO

Vocal learning, the ability to modify the acoustic structure of vocalizations based on social experience, is a fundamental feature of speech in humans (Homo sapiens). While vocal learning is common in taxa such as songbirds and whales, the vocal learning capacities of nonhuman primates appear more limited. Intriguingly, evidence for vocal learning has been reported in chimpanzees (Pan troglodytes), for example, in the form of regional variation ("dialects") in the "pant-hoot" calls. This suggests that some capacity for vocal learning may be an ancient feature of the Pan-Homo clade. Nonetheless, reported differences have been subtle, with intercommunity variation representing only a small portion of the total acoustic variation. To gain further insights into the extent of regional variation in chimpanzee vocalizations, we performed an analysis of pant-hoots from chimpanzees in the neighboring Kasekela and Mitumba communities at Gombe National Park, Tanzania, and the geographically distant Kanyawara community at Kibale National Park, Uganda. We did not find any statistically significant differences between the neighboring communities at Gombe or among geographically distant communities. Furthermore, we found differences among individuals in all communities. Hence, the variation in chimpanzee pant-hoots reflected individual differences, rather than group differences. Thus, we did not find evidence of dialects in this population, suggesting that extensive vocal learning emerged only after the lineages of Homo and Pan diverged.


Assuntos
Hominidae , Pan troglodytes , Acústica , Animais , Humanos , Individualidade , Vocalização Animal
5.
Philos Trans R Soc Lond B Biol Sci ; 377(1851): 20210151, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35369753

RESUMO

Group territory defence poses a collective action problem: individuals can free-ride, benefiting without paying the costs. Individual heterogeneity has been proposed to solve such problems, as individuals high in reproductive success, rank, fighting ability or motivation may benefit from defending territories even if others free-ride. To test this hypothesis, we analysed 30 years of data from chimpanzees (Pan troglodytes) in the Kasekela community, Gombe National Park, Tanzania (1978-2007). We examined the extent to which individual participation in patrols varied according to correlates of reproductive success (mating rate, rank, age), fighting ability (hunting), motivation (scores from personality ratings), costs of defecting (the number of adult males in the community) and gregariousness (sighting frequency). By contrast to expectations from collective action theory, males participated in patrols at consistently high rates (mean ± s.d. = 74.5 ± 11.1% of patrols, n = 23 males). The best predictors of patrol participation were sighting frequency, age and hunting participation. Current and former alpha males did not participate at a higher rate than males that never achieved alpha status. These findings suggest that the temptation to free-ride is low, and that a mutualistic mechanism such as group augmentation may better explain individual participation in group territorial behaviour. This article is part of the theme issue 'Intergroup conflict across taxa'.


Assuntos
Pan troglodytes , Territorialidade , Animais , Humanos , Masculino , Motivação , Personalidade , Reprodução
6.
J Geriatr Oncol ; 12(8): 1208-1213, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34272204

RESUMO

INTRODUCTION: Treatment toxicities are common in older adults with cancer and consequently, treatment modifications are sometimes considered. We evaluated the prevalence and factors associated with treatment modifications at the first cycle in older patients receiving palliative systemic treatment. METHODS: Patients (n = 369) from the GAP 70+ Trial (NCT02054741; PI: Mohile) usual care arm were included. Enrolled patients were aged 70+ with advanced cancer and ≥ 1 Geriatric Assessment (GA) domain impairment. Treatment modification was defined as any change from National Comprehensive Cancer Network guidelines or published clinical trials. Baseline variables included: 1) sociodemographic factors; 2) clinical variables; 3) GA domains; and 4) physician beliefs about life expectancy. Bivariate analyses and multivariable cluster-weighted generalized estimating equation model were conducted to assess the association of baseline variables with cycle 1 treatment modifications. RESULTS: Mean age was 77.2 years (range: 70-94); 62% had lung or gastrointestinal cancers, and 35% had treatment modifications at cycle 1. Increasing age by one year (odds ratio (OR) 1.1, 95% confidence interval [CI] 1.0-1.2), receipt of ≥second line of chemotherapy (OR 1.8, CI 1.1-3.0), functional impairment (OR 1.6, CI 1.1-2.3) and income ≤$50,000 (OR 1.7, CI 1.1-2.4) were independently associated with a higher likelihood of cycle 1 treatment modification. CONCLUSION: Treatment modifications occurred in 35% of older adults with advanced cancer at cycle 1. Increasing age, receipt of ≥second line of chemotherapy, functional impairment, and lower income were independently associated with treatment modifications. These findings emphasize the need for evidence-based regimens in older adults with cancer and GA impairments.


Assuntos
Neoplasias , Cuidados Paliativos , Idoso , Idoso de 80 Anos ou mais , Avaliação Geriátrica , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Prevalência , Fatores Sociodemográficos
7.
Exp Brain Res ; 239(4): 1085-1098, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33543322

RESUMO

When humans handle a tool, such as a tennis racket or hammer, for the first time, they often wield it to determine its inertial properties. The mechanisms that contribute to perception of inertial properties are not fully understood. The present study's goal was to investigate how proprioceptive afferents contribute to effortful perception of heaviness and length of a manually wielded object in the absence of vision. Blindfolded participants manually wielded specially designed objects with different mass, the static moment, and the moment of inertia at different wrist angles and angular kinematics. These manipulations elicited different tonic and rhythmic activity levels in the muscle spindles of the wrist, allowing us to relate differences in muscle activity to perceptual judgments of heaviness and length. Perception of heaviness and length depended on an object's static moment and the moment of inertia, respectively. Manipulations of wrist angle and angular kinematics affected perceived heaviness and length in distinct ways. Ulnar deviation resulted in an object being perceived heavier but shorter. Compared to static holding, wielding the object resulted in it being perceived heavier but wielding did not affect perceived length. These results suggest that proprioceptive afferents differentially contribute to effortful perception of object heaviness and length. Critically, the role of afferent is specific to the mechanical variable used to derive a given object property. These findings open a new possibility of studies on the link between physiology, and different mechanical variables picked up by the perceptual system.


Assuntos
Percepção de Peso , Fenômenos Biomecânicos , Humanos , Julgamento , Propriocepção , Percepção de Tamanho , Punho
8.
Mol Cancer Res ; 18(12): 1777-1788, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32855269

RESUMO

The NF-E2-related factor 2 (referred to as NRF2) transcription factor binds antioxidant responsive elements within the promoters of cytoprotective genes to induce their expression. Next-generation sequencing studies in lung cancer have shown a significant number of activating mutations within the NRF2 signaling pathway. Mutations in components of the SWI/SNF chromatin-remodeling complex, a general regulator of transcription using either BRG1 or BRM as the catalytic subunit, also frequently occur in lung cancers. Importantly, low BRG1 expression levels in primary human NSCLC correlated with increased NRF2-target gene expression. Here, we show that loss of SWI/SNF complex function activated a subset of NRF2-mediated transcriptional targets. Using a series of isogenic NSCLC lines with reduced or depleted BRG1 and/or BRM expression, we observed significantly increased expression of the NRF2-target genes HMOX1 and GSTM4. In contrast, expression of the NRF2 target genes NQO1 and GCLM modestly increased following BRM reduction. Chromatin immunoprecipitation showed that BRG1 knockdown led to increased NRF2 binding at its respective ARE sites in the HMOX1 promoter but not in NQO1 and GCLM. Our data demonstrate that loss of BRG1 or BRM in lung cancer results in activation of the NRF2/KEAP1 pathway and HMOX1 expression. Therefore, we provide an additional molecular explanation for why patients harboring BRG1 or BRM mutations show poor prognoses. A better understanding of this mechanism may yield novel insights into the design of targeted treatment modalities. IMPLICATIONS: Our study identifies a novel mechanism for how mutations in the SMARCA4 gene may drive progression of human lung adenocarcinomas.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , DNA Helicases/genética , Neoplasias Pulmonares/genética , Proteínas Nucleares/genética , Análise de Sequência de DNA/métodos , Transdução de Sinais , Fatores de Transcrição/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina , Regulação Neoplásica da Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutationa Transferase/genética , Heme Oxigenase-1/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Mutação , NAD(P)H Desidrogenase (Quinona)/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo
9.
J Comp Psychol ; 133(2): 156-170, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30307263

RESUMO

Existing models of attachment do not explain how death of offspring affects maternal behavior. Previous descriptions of maternal responsiveness to dead offspring in nonhuman anthropoids have not expounded the wide variation of deceased-infant carrying (DIC) behavior. Through the current study, we attempt to (a) identify determinants of DIC through a systematic survey across anthropoids, (b) quantitatively assess behavioral changes of mother during DIC, and (c) infer death perception of conspecifics. Firstly, we performed phylogenetic regression using duration of DIC as the dependent variable. Secondly, we undertook case studies of DIC in the bonnet monkey and the lion-tailed monkey through behavioral sampling. Results of phylogenetic Generalized Linear Mixed Model (Nspecies = 18; Ncases = 48) revealed a strong homology (H2 = 0.86). We also obtained a high intraspecific variation in DIC and found DIC to be affected by mother's age, context of death, habitat condition, and degree of arboreality. We found bonnet mothers to carry their deceased offspring for 3.56 ± 4.03 SD days (N = 7) with diminished feeding, enhanced passivity, and social isolation during DIC and progressive decline in protection/attentiveness of corpse and attachment. Following Anderson (2016)'s framework of death perception, we interpreted repeated sensory investigation of corpses by mothers as comprehending causality of death, inanimate handling of corpse and its defense as comprehension of non-functionality, and a progressive disinterest of mothers in them as perceiving irreversibility of death. Lastly, we integrated DIC with mother-infant attachment theories and proposed a conceptual model characterizing DIC with causal determinants. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Comportamento Animal/fisiologia , Morte , Macaca radiata/fisiologia , Macaca/fisiologia , Comportamento Materno/fisiologia , Apego ao Objeto , Animais , Feminino , Humanos
10.
J Theor Biol ; 390: 50-60, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26620631

RESUMO

Laterally asymmetrical movements are ubiquitous among organisms. A bilaterally symmetrical organism cannot maneuver through a two- or three-dimensional space unless and until one side of its body leads, because the forces that cause the movements of the body are generated within the body. One question follows: are there any costs or benefits of laterally asymmetrical movements? We test whether directionally consistent laterally asymmetrical movements at different levels of organization of movements (at the individual, and not the population level) can work synergistically. We show-by means of a hypothetical system resembling a humanoid robot-that a laterally asymmetrical movement at a lower level of organization of movements can stimulate laterally asymmetrical movements that are directionally consistent at consecutive higher levels. We show-by comparing two hypothetical systems, incorporating laterally symmetrical and asymmetrical movements, respectively-that the asymmetrical system outperforms the symmetrical system by optimizing space and time and that this space-time advantage increases with the increasing complexity of the task. Together, these results suggest that laterally asymmetrical movements can self-organize as a consequence of space-time optimization.


Assuntos
Algoritmos , Lateralidade Funcional/fisiologia , Modelos Biológicos , Movimento/fisiologia , Animais , Fenômenos Biomecânicos , Humanos , Desempenho Psicomotor/fisiologia , Fatores de Tempo
11.
PLoS One ; 10(3): e0119337, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25806511

RESUMO

A practical approach to understanding lateral asymmetries in body, brain, and cognition would be to examine the performance advantages/disadvantages associated with the corresponding functions and behavior. In the present study, we examined whether the division of labor in hand usage, marked by the preferential usage of the two hands across manual operations requiring maneuvering in three-dimensional space (e.g., reaching for food, grooming, and hitting an opponent) and those requiring physical strength (e.g., climbing), is associated with higher hand performance in free-ranging bonnet macaques, Macaca radiate [corrected]. We determined the extent to which the macaques exhibit laterality in hand usage in an experimental unimanual and a bimanual food-reaching task, and the extent to which manual laterality is associated with hand performance in an experimental hand-performance-differentiation task. We observed negative relationships between (a) the latency in food extraction by the preferred hand in the hand-performance-differentiation task (wherein, lower latency implies higher performance), the preferred hand determined using the bimanual food-reaching task, and the normalized difference between the performance of the two hands, and (b) the normalized difference between the performance of the two hands and the absolute difference between the laterality in hand usage in the unimanual and the bimanual food-reaching tasks (wherein, lesser difference implies higher manual specialization). Collectively, these observations demonstrate that the division of labor between the two hands is associated with higher hand performance.


Assuntos
Lateralidade Funcional/fisiologia , Mãos/fisiologia , Desempenho Psicomotor/fisiologia , Animais , Feminino , Alimentos , Macaca radiata , Masculino
12.
Cancer Res ; 74(22): 6486-6498, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25115300

RESUMO

SWI/SNF chromatin remodeling complexes regulate critical cellular processes, including cell-cycle control, programmed cell death, differentiation, genomic instability, and DNA repair. Inactivation of this class of chromatin remodeling complex has been associated with a variety of malignancies, including lung, ovarian, renal, liver, and pediatric cancers. In particular, approximately 10% of primary human lung non-small cell lung cancers (NSCLC) display attenuations in the BRG1 ATPase, a core factor in SWI/SNF complexes. To evaluate the role of BRG1 attenuation in NSCLC development, we examined the effect of BRG1 silencing in primary and established human NSCLC cells. BRG1 loss altered cellular morphology and increased tumorigenic potential. Gene expression analyses showed reduced expression of genes known to be associated with progression of human NSCLC. We demonstrated that BRG1 losses in NSCLC cells were associated with variations in chromatin structure, including differences in nucleosome positioning and occupancy surrounding transcriptional start sites of disease-relevant genes. Our results offer direct evidence that BRG1 attenuation contributes to NSCLC aggressiveness by altering nucleosome positioning at a wide range of genes, including key cancer-associated genes.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Cromatina/fisiologia , DNA Helicases/fisiologia , Neoplasias Pulmonares/patologia , Proteínas Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , DNA Helicases/genética , Metilação de DNA , Progressão da Doença , Feminino , Humanos , Camundongos , Proteínas Nucleares/genética , Nucleossomos , Fatores de Transcrição/genética
13.
PLoS One ; 9(5): e97971, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24844660

RESUMO

There can be several factors that are likely to have played a role in the evolution of hand preference in humans and non-human primates, which the existing theories do not consider. There exists a possibility that hand preference in non-human primates evolved from the pre-existing lateralities in more elementary brain functions and behavior, or alternatively, the two coevolved. A basic example can be a hand-mouth command system that could have evolved in the context of ingestion. In the present study, we examined the relationship between lateralities in prehension and mastication processes, that is, hand and cheek pouch usage, in free-ranging bonnet macaques, Macaca radiata. The macaques preferentially used one hand-the 'preferred' hand, to pick up the bananas lying on the ground. Lateralities in hand and cheek pouch usage (for both filling and emptying) were positively related with each other, that is, the macaques used the cheek pouch corresponding to the preferred hand predominantly and before the other. Moreover, when the macaques used the non-preferred hand to pick up the bananas, the frequency of contralateral cheek pouch usage was higher than the frequency of ipsilateral cheek pouch usage, that is, the combined structure of hand, mouth, and food did not influence the relationship between laterality in hand usage and laterality in cheek pouch usage. These findings demonstrate laterality in a relatively more involuntary function than those explored previously in any non-human primate species (e.g., facial expressions and manual gestures).


Assuntos
Bochecha , Comportamento Alimentar , Lateralidade Funcional , Mãos , Animais , Evolução Biológica , Feminino , Haplorrinos , Macaca , Masculino
14.
Am J Primatol ; 76(6): 576-85, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24375912

RESUMO

Primates exhibit laterality in hand usage either in terms of (a) hand with which an individual solves a task or while solving a task that requires both hands, executes the most complex action, that is, "hand preference," or (b) hand with which an individual executes actions most efficiently, that is, "hand performance." Observations from previous studies indicate that laterality in hand usage might reflect specialization of the two hands for accomplishing tasks that require maneuvering dexterity or physical strength. However, no existing study has investigated handedness with regard to this possibility. In this study, we examined laterality in hand usage in urban free-ranging bonnet macaques, Macaca radiata with regard to the above possibility. While solving four distinct food extraction tasks which varied in the number of steps involved in the food extraction process and the dexterity required in executing the individual steps, the macaques consistently used one hand for extracting food (i.e., task requiring maneuvering dexterity)-the "maneuvering" hand, and the other hand for supporting the body (i.e., task requiring physical strength)-the "supporting" hand. Analogously, the macaques used the maneuvering hand for the spontaneous routine activities that involved maneuvering in three-dimensional space, such as grooming, and hitting an opponent during an agonistic interaction, and the supporting hand for those that required physical strength, such as pulling the body up while climbing. Moreover, while solving a task that ergonomically forced the usage of a particular hand, the macaques extracted food faster with the maneuvering hand as compared to the supporting hand, demonstrating the higher maneuvering dexterity of the maneuvering hand. As opposed to the conventional ideas of handedness in non-human primates, these observations demonstrate division of labor between the two hands marked by their consistent usage across spontaneous and experimental tasks requiring maneuvering in three-dimensional space or those requiring physical strength.


Assuntos
Comportamento Animal , Lateralidade Funcional , Mãos , Macaca radiata/psicologia , Animais , Feminino , Masculino
16.
Health Phys ; 102(1): 54-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22134078

RESUMO

Recent studies have shown that exposing human semen samples to cell phone radiation leads to a significant decline in sperm parameters. In daily living, a cell phone is usually kept in proximity to the groin, such as in a trouser pocket, separated from the testes by multiple layers of tissue. The aim of this study was to calculate the distance between cell phone and semen sample to set up an in vitro experiment that can mimic real life conditions (cell phone in trouser pocket separated by multiple tissue layers). For this reason, a computational model of scrotal tissues was designed by considering these separating layers, the results of which were used in a series of simulations using the Finite Difference Time Domain (FDTD) method. To provide an equivalent effect of multiple tissue layers, these results showed that the distance between a cell phone and semen sample should be 0.8 cm to 1.8 cm greater than the anticipated distance between a cell phone and the testes.


Assuntos
Sêmen/efeitos da radiação , Espermatozoides/efeitos da radiação , Testículo/efeitos da radiação , Algoritmos , Telefone Celular , Simulação por Computador , Humanos , Técnicas In Vitro , Masculino , Modelos Anatômicos , Ondas de Rádio , Escroto/patologia , Escroto/efeitos da radiação , Fatores de Tempo
17.
J Med Case Rep ; 4: 379, 2010 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-21108779

RESUMO

INTRODUCTION: Choriocarcinoma is a highly malignant tumor of trophoblastic origin. Most cases present within one year of the antecedent pregnancy (molar or non-molar). However, very rarely, choriocarcinoma can develop from germ cells or from dedifferentiation of endometrial carcinoma into choriocarcinoma. This article concerns a case of choriocarcinoma developing 38 years after the patient's last pregnancy and 23 years after menopause. CASE PRESENTATION: A 73-year-old African-American woman presented with a three-week history of vaginal bleeding. A vaginal mass was seen on pelvic examination. Ultrasonography showed a thickened complex endometrial echo. Her ß-human chorionic gonadotrophin level was found to be elevated (2,704,040 mIU/mL). Vaginal and uterine biopsies were suggestive of choriocarcinoma. Immunohistochemistry tests were positive for ß-human chorionic gonadotrophin as well as cytokeratin and negative for octamer binding transcription factor 3/4 and α-fetoprotein, supporting the diagnosis of choriocarcinoma. A combination of etoposide, methotrexate, and dactinomycin, followed by cyclophosphamide and vincristine (the so-called EMA/CO regimen) was initiated. After seven cycles of chemotherapy, her ß-human chorionic gonadotrophin level dropped below 5 mIU/mL. Our patient is being followed up at our oncology institute. CONCLUSIONS: We report an extremely rare case of choriocarcinoma arising 23 years after menopause. A postmenopausal woman presenting with vaginal bleed from a mass and ß-human chorionic gonadotrophin elevation should be evaluated by immunohistochemical analysis to rule out the possibilities of a germ cell origin of the tumor or dedifferentiation of an epithelial tumor. Absence of octamer binding transcription factor 3/4, α-fetoprotein and CD-30 staining helps in exclusion of most germ cell tumors. DNA polymorphism studies can be used to differentiate between gestational and non-gestational tumor origin. These require fresh tissue samples and are time consuming. Finally, the effective first-line therapy for ß-human chorionic gonadotrophin-producing high-risk gestational as well as non-gestational trophoblastic tumors is combination chemotherapy (the EMA/CO regimen). Therefore, treatment should be commenced when a potential diagnosis of metastatic trophoblastic tumor is being considered.

18.
Case Rep Med ; 2010: 406102, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20300549

RESUMO

Background. Monoclonal gammopathy of undetermined significance (MGUS) is rarely complicated by amyloidosis. Case. A 66-year-old white male presented to the emergency room (ER) after an unwitnessed fall and change in mental status. Patient was awake and alert but not oriented. There was no focal deficit on neurological exam. Past medical history (PMH) included hypertension, hypercholesterolemia, aortic valve replacement (nonmetallic), incomplete heart block controlled by a pacemaker and IgG- IgA type Monoclonal Gammopathy of Undetermined Significance. The MGUS was diagnosed 9 months ago on serum protein electrophoresis (SPEP) as patient was referred to the outpatient clinic for hyperglobulinemia on routine blood work. In ER, a head-computed tomography (CT) revealed multiple parenchymal hemorrhagic lesions suspicious for metastases. A CT chest, abdomen and pelvis revealed numerous ground-glass and solid nodules in the lungs. Lower extremity duplex and transesophageal echocardiogram were negative. Serial blood cultures and serologies for cryptococcus and histoplasmosis, antineutrophil cytoplasmic antibody (ANCA), antinuclear antibody (ANA), rheumatoid factor (RF), cryoglobulin, and antiglomerular basement membrane (anti-GBM) antibodies were all negative. CT guided lung biopsy was positive for Thioflavin T amyloid deposits. Brain biopsy was positive for eosinophilic material (similar to the lungs) but negative for Thioflavin T stain. The patient's clinical status continued to deteriorate with cold cyanotic fingers developing on day 12 and a health care acquired pneumonia, respiratory failure, and fungemia on day 18. On day 29, family withdrew life support and denied any autopsies. Conclusion. Described is an atypical course of MGUS complicated by amyloidosis of the lung and nonamyloid eosinophilic deposition in the brain. As MGUS might be complicated by diseases such as amyloidosis and multiple myeloma, a scheduled follow-up of these patients is always necessary. Further research is needed in order to better define the optimal treatment and management strategies of MGUS and its complications.

19.
Fertil Steril ; 94(4): 1541-1543, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20117777

RESUMO

In a longitudinal study over a period of 21 months, we demonstrated that seminal reactive oxygen species (ROS) levels are independent of sperm concentration, motility, and abstinence duration within a healthy sperm donor, although some variations were observed in ROS levels. We suggest that fluctuation in seminal ROS values may be related to physiologic or transient changes in spermatogenesis.


Assuntos
Fertilidade/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Abstinência Sexual/fisiologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides/fisiologia , Saúde , Humanos , Estudos Longitudinais , Masculino , Espermatogênese/fisiologia , Espermatozoides/metabolismo , Fatores de Tempo
20.
Urology ; 75(1): 14-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19616285

RESUMO

This review examines the effect of mitochondrial generation of reactive oxygen species (ROS) and aging on human spermatozoa and seminal antioxidants. We discuss the effect of continuous ROS production on biomarkers of aging, such as germ cell telomeres and telomerase, lipofuscin, and amyloid. These markers may be responsible for telomere shortening and subsequent decrease in sperm count, decline in testosterone concentration, and decline in motility with aging. Excessive ROS can also damage mitochondrial deoxyribonucleic acid and sperm nuclear DNA, contributing to paternally transmitted diseases. ROS generation has a central role in the pathophysiology of age-related decrease in male fertility.


Assuntos
Envelhecimento/metabolismo , Radicais Livres/metabolismo , Infertilidade Masculina/etiologia , Infertilidade Masculina/metabolismo , Humanos , Masculino , Espermatozoides/metabolismo , Telomerase/metabolismo
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