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1.
J Exp Biol ; 227(12)2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38869075

ABSTRACT

Lepidosaurian reptiles, particularly snakes, periodically shed the outer epidermal layers of their skin (ecdysis) to restore or enhance vital functions such as regulating water and gaseous exchange, growth, and protection against insult, infection or physical injury. Although many studies have focused on the nature and mechanisms of skin shedding, little attention has been paid to the timing of the first ecdysis in neonates following birth or hatching. A recent study investigated patterns of the time to first postnatal ecdysis in snakes based on a large dataset taken from the literature. The analysis demonstrated patterns in the time to first postnatal ecdysis related to phylogeny as well as several life history traits. While this assessment provides important advances in our knowledge of this topic, data on known biophysical drivers of ecdysis - temperature and humidity - were largely unavailable and were not evaluated. The first postnatal ecdysis of neonatal snakes can be viewed as an adaptive adjustment to the transition from the aqueous environment of the embryo to the aerial environment of the newborn. Hence, the timing of the first postnatal ecdysis is logically influenced by the aerial environment into which a newborn snake or hatchling finds itself. Therefore, in this Commentary, we first emphasize the putative plasticity of ecdysis with respect to epidermal lipids that structure the water permeability barrier and are established or renewed during ecdysis to reduce transepidermal evaporative water loss. We then discuss the likely importance of biophysical variables as influential covariates that need future investigation as potential co-determinants of the timing of first postnatal ecdysis.


Subject(s)
Molting , Snakes , Animals , Snakes/physiology , Snakes/growth & development , Molting/physiology , Time Factors , Animals, Newborn/physiology , Animals, Newborn/growth & development
2.
Microbiome ; 12(1): 74, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38622632

ABSTRACT

BACKGROUND: The equine gastrointestinal (GI) microbiome has been described in the context of various diseases. The observed changes, however, have not been linked to host function and therefore it remains unclear how specific changes in the microbiome alter cellular and molecular pathways within the GI tract. Further, non-invasive techniques to examine the host gene expression profile of the GI mucosa have been described in horses but not evaluated in response to interventions. Therefore, the objectives of our study were to (1) profile gene expression and metabolomic changes in an equine model of non-steroidal anti-inflammatory drug (NSAID)-induced intestinal inflammation and (2) apply computational data integration methods to examine host-microbiota interactions. METHODS: Twenty horses were randomly assigned to 1 of 2 groups (n = 10): control (placebo paste) or NSAID (phenylbutazone 4.4 mg/kg orally once daily for 9 days). Fecal samples were collected on days 0 and 10 and analyzed with respect to microbiota (16S rDNA gene sequencing), metabolomic (untargeted metabolites), and host exfoliated cell transcriptomic (exfoliome) changes. Data were analyzed and integrated using a variety of computational techniques, and underlying regulatory mechanisms were inferred from features that were commonly identified by all computational approaches. RESULTS: Phenylbutazone induced alterations in the microbiota, metabolome, and host transcriptome. Data integration identified correlation of specific bacterial genera with expression of several genes and metabolites that were linked to oxidative stress. Concomitant microbiota and metabolite changes resulted in the initiation of endoplasmic reticulum stress and unfolded protein response within the intestinal mucosa. CONCLUSIONS: Results of integrative analysis identified an important role for oxidative stress, and subsequent cell signaling responses, in a large animal model of GI inflammation. The computational approaches for combining non-invasive platforms for unbiased assessment of host GI responses (e.g., exfoliomics) with metabolomic and microbiota changes have broad application for the field of gastroenterology. Video Abstract.


Subject(s)
Microbiota , Animals , Horses/genetics , Intestinal Mucosa/metabolism , Metabolome , Feces/microbiology , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Inflammation/metabolism , Phenylbutazone/metabolism , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 16S/metabolism
3.
Ann Bot ; 133(1): 153-168, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-37665952

ABSTRACT

BACKGROUND AND AIMS: Kelp forests underpin temperate marine ecosystems but are declining due to ocean warming, causing loss of associated ecosystem services. Projections suggest significant future decline but often only consider the persistence of adult sporophytes. Kelps have a biphasic life cycle, and the haploid gametophyte can be more thermally tolerant than the sporophyte. Therefore, projections may be altered when considering the thermal tolerance of gametophytes. METHODS: We undertook thermal tolerance experiments to quantify the effect of temperature on gametophyte survival, relative growth rate (RGR) and sex ratio for three genetically distinct populations of Ecklonia radiata gametophytes from comparatively high, mid- and low latitudes (43°, 33° and 30°S). We then used these data to project the likely consequences of climate-induced thermal change on gametophyte persistence and performance across its eastern Australian range, using generalized additive and linear models. KEY RESULTS: All populations were adapted to local temperatures and their thermal maximum was 2-3 °C above current maximum in situ temperatures. The lowest latitude population was most thermally tolerant (~70 % survival up to 27 °C), while survival and RGR decreased beyond 25.5 and 20.5 °C for the mid- and low-latitude populations, respectively. Sex ratios were skewed towards females with increased temperature in the low- and high-latitude populations. Spatially explicit model projections under future ocean warming (2050-centred) revealed a minimal decline in survival (0-30 %) across populations, relative to present-day predictions. RGRs were also projected to decline minimally (0-2 % d-1). CONCLUSIONS: Our results contrast with projections for the sporophyte stage of E. radiata, which suggest a 257-km range contraction concurrent with loss of the low-latitude population by 2100. Thermal adaptation in E. radiata gametophytes suggests this life stage is likely resilient to future ocean warming and is unlikely to be a bottleneck for the future persistence of kelp.


Subject(s)
Kelp , Animals , Climate Change , Ecosystem , Germ Cells, Plant , Australia , Temperature
4.
PLoS One ; 18(12): e0289249, 2023.
Article in English | MEDLINE | ID: mdl-38085721

ABSTRACT

Conflicting claims exist regarding pathogen growth in raw milk. A small pilot study was designed to provide definitive data on trends for pathogen growth and decline in raw bovine milk hygienically produced for direct human consumption. An independent laboratory conducted the study, monitoring growth and decline of pathogens inoculated into raw milk. Raw milk samples were inoculated with foodborne pathogens (Campylobacter, E. coli O157:H7, Listeria monocytogenes, or Salmonella) at lower (<162 colony forming units (CFU) per mL) and higher levels (<8,300 CFU/mL). Samples were stored at 4.4°C and quantified over time after inoculation (days 0, 3, 6, 9, 12, and 14) by standard culture-based methods. Statistical analysis of trends using the Mann-Kendall Trend Test and Analysis of Variance were conducted for 48 time series observations. Evidence of pathogen growth was documented for L. monocytogenes in 8 of 12 replicates (P = 0.001 to P = 0.028). Analysis of variance confirmed significant increases for L. monocytogenes at both initial levels in week 2. No evidence of growth was documented over 14 days for the three pathogens predominantly associated with raw milk outbreaks in the US (Campylobacter, E. coli O157:H7, and Salmonella). Further research is needed to characterize parameters for pathogen growth and decline to support re-assessment of risks that were based on incorrect assumptions about interactions of pathogens with the raw milk microbiota.


Subject(s)
Escherichia coli O157 , Listeria monocytogenes , Humans , Animals , Milk , Food Microbiology , Pilot Projects , Colony Count, Microbial , Salmonella
6.
Zookeys ; 1145: 131-167, 2023.
Article in English | MEDLINE | ID: mdl-37234698

ABSTRACT

A new species of Dipsas Laurenti, 1768, from Central Panama is described based on molecular analyses, hemipenial morphology, and external characters. This is the sixth species of Dipsas to be described for the country; the snake has been suspected to exist since 1977 and has not been thoroughly studied until now. Additionally, morphological comparations including scale counts are done with other species within the genus, and the current geographic distribution of Dipsastemporalis (Werner, 1909), the sister species, is updated. Finally, a key to the species of Dipsas currently known from Middle America is presented.


ResumenDescribimos una nueva especies de Dipsas Laurenti, 1768 de la región central de Panamá en base a análisis moleculares, morfología hemipenial y caracteres de morfología externa. Esta es la sexta especie del género Dipsas descrita para el país. Se sospechaba su existencia desde 1977 pero no había sido estudiada exhaustivamente hasta ahora. Adicionalmente, presentamos comparaciones morfológicas (incluyendo lepidosis) con otras especies del género y actualizamos la distribución geográfica de su especie hermana Dipsastemporalis (Werner, 1909). Finalmente, presentamos una clave para las especies de Dipsas distribuidas en Centroamérica.

7.
Mol Psychiatry ; 28(6): 2301-2311, 2023 06.
Article in English | MEDLINE | ID: mdl-37173451

ABSTRACT

BACKGROUND: Alterations in brain connectivity may underlie neuropsychiatric conditions such as schizophrenia. We here assessed the degree of convergence of frontostriatal fiber projections in 56 young adult healthy controls (HCs) and 108 matched Early Psychosis-Non-Affective patients (EP-NAs) using our novel fiber cluster analysis of whole brain diffusion magnetic resonance imaging tractography. METHODS: Using whole brain tractography and our fiber clustering methodology on harmonized diffusion magnetic resonance imaging data from the Human Connectome Project for Early Psychosis we identified 17 white matter fiber clusters that connect frontal cortex (FCtx) and caudate (Cd) per hemisphere in each group. To quantify the degree of convergence and, hence, topographical relationship of these fiber clusters, we measured the inter-cluster mean distances between the endpoints of the fiber clusters at the level of the FCtx and of the Cd, respectively. RESULTS: We found (1) in both groups, bilaterally, a non-linear relationship, yielding convex curves, between FCtx and Cd distances for FCtx-Cd connecting fiber clusters, driven by a cluster projecting from inferior frontal gyrus; however, in the right hemisphere, the convex curve was more flattened in EP-NAs; (2) that cluster pairs in the right (p = 0.03), but not left (p = 0.13), hemisphere were significantly more convergent in HCs vs EP-NAs; (3) in both groups, bilaterally, similar clusters projected significantly convergently to the Cd; and, (4) a significant group by fiber cluster pair interaction for 2 right hemisphere fiber clusters (numbers 5, 11; p = .00023; p = .00023) originating in selective PFC subregions. CONCLUSIONS: In both groups, we found the FCtx-Cd wiring pattern deviated from a strictly topographic relationship and that similar clusters projected significantly more convergently to the Cd. Interestingly, we also found a significantly more convergent pattern of connectivity in HCs in the right hemisphere and that 2 clusters from PFC subregions in the right hemisphere significantly differed in their pattern of connectivity between groups.


Subject(s)
Psychotic Disorders , White Matter , Young Adult , Humans , Healthy Volunteers , Cadmium , White Matter/pathology , Brain/pathology , Psychotic Disorders/diagnostic imaging , Psychotic Disorders/pathology
8.
Anaesth Rep ; 11(1): e12230, 2023.
Article in English | MEDLINE | ID: mdl-37216042
9.
Gulf J Oncolog ; 1(41): 23-31, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36804156

ABSTRACT

INTRODUCTION: To assess progress against cancer, trends in incidence, survival and mortality need to be interpreted simultaneously. METHODS: Data were obtained from the Kuwait Cancer Registry (KCR) for all Kuwaiti children (0-14 years) and adults (15-99 years) diagnosed with one of 18 common cancers during 2000-2013, with follow-up for vital status to 31 December 2015. World-standardised average annual incidence and mortality rates were calculated for 2000-2004, 2005-2009, 2010-2013. Five-year net survival was estimated with the Pohar Perme estimator, corrected for background mortality using life tables of all-cause mortality. Survival estimates were agestandardised using the International Cancer Survival Standard weights. RESULTS: For liver cancer, five-year net survival increased from 11.4% to 13.4% for patients diagnosed between 2000-2004 and 2010-2013, while incidence and mortality rates fell from 5.5 to 3.6 and from 3.9 to 3.0 per 100,000, respectively. Similar patterns were seen for acute lymphoblastic leukaemia (ALL) and lymphoma in children. Survival and mortality remained stable for cancers of the lung, cervix and ovary, but incidence declined from 10.2 to 7.4, 4.9 to 2.4 and 5.8 to 4.3 per 100,000, respectively. For breast cancer, survival increased from 68.3% to 75.2%, while incidence and mortality rose from 45.6 to 58.7 and from 5.8 to 12.8 per 100,000, respectively. For colon cancer, incidence and mortality rates rose from 11.4 to 12.6 and from 2.3 to 5.4 per 100,000, respectively. Five-year survival fell from 64.8% to 50.2% between 2000-2004 and 2005-2009, before rising to 58.5% for 2010-2013. CONCLUSION: Increasing survival, alongside falling incidence and mortality rates, represents progress in cancer control, attributable to effective prevention (e.g. tobacco control and lung cancer) and early diagnostic activity (e.g. mammography for breast cancer), or better treatment (e.g. childhood ALL). The increasing prevalence of obesity, linked to rising incidence for breast and colon cancers, suggests the need for public health prevention campaigns.


Subject(s)
Breast Neoplasms , Colonic Neoplasms , Neoplasms , Adult , Child , Female , Humans , Incidence , Kuwait/epidemiology , Neoplasms/pathology , Registries , Prevalence
10.
Psychotherapy (Chic) ; 60(1): 27-38, 2023 03.
Article in English | MEDLINE | ID: mdl-34843315

ABSTRACT

Studies suggest that racism affects the type and quality of health care that patients who are Black receive, perhaps in part because poorer patient-provider communication and less provider encouragement of patient involvement have been consistently reported for patients of color. In particular, Black women are 3-4 times more likely to experience dangerous and even life-threatening complications, and more likely to report mistreatment and neglect from medical providers and staff, during childbirth. Experiences with gendered racism during childbirth, which in itself is a vulnerable, intense, and potentially traumatic experience when proper support is absent, may lead to posttraumatic stress reactions. Psychotherapy can help affected clients to process gendered racial and childbirth traumas through: (a) the establishment of a safe, trusting, and collaborative therapeutic relationship, in which careful attention is paid to repairing alliance ruptures caused by cultural misunderstandings or gendered racial microaggressions, and (b) framing experiences and "symptoms" as understandable reactions to gendered race-based traumatic stress during childbirth. In addition to direct therapeutic intervention, therapists should collaborate with doulas and/or medical providers on patient care, and, separately, advocate for systemic-level change, supporting clients' lived experiences outside of the therapy room. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Subject(s)
Racism , Humans , Pregnancy , Female , Psychotherapy
11.
Arch Sex Behav ; 52(4): 1403-1415, 2023 05.
Article in English | MEDLINE | ID: mdl-36469144

ABSTRACT

To date, there has been very little empirical research on Black women's masturbation practices and views on masturbation. This study fills the gap by exploring the messages Black women received about masturbation and self-pleasure and the sources of these messages using valence theory. Data were collected in 2021 from 242 Black women who participated in a survey during phase one of the triphasic Big Sex Study. Thematic analysis was used to analyze this short-form qualitative data. Results indicated a range of responses, with mixed messages reported more than negative, positive, and neutral messages. The three primary sources of messages were religion, family, and friends. There were several themes across the valence of messages including the development of positive messages, sexual self-awareness, masturbation as sin, health benefits and consequences, relationship difficulties, devaluation, and masturbation as dirty and gross. These results provide a basis for sexuality professionals to improve sociocultural knowledge about masturbation beliefs, practices, and message sources among Black women.


Subject(s)
Masturbation , Sexual Behavior , Female , Humans , Sexuality , Perception , Surveys and Questionnaires
14.
J Geophys Res Planets ; 127(7): e2021JE007149, 2022 Jul.
Article in English | MEDLINE | ID: mdl-36247718

ABSTRACT

The current rate of small impacts on Mars is informed by more than one thousand impact sites formed in the last 20 years, detected in images of the martian surface. More than half of these impacts produced a cluster of small craters formed by fragmentation of the meteoroid in the martian atmosphere. The spatial distributions, number and sizes of craters in these clusters provide valuable constraints on the properties of the impacting meteoroid population as well as the meteoroid fragmentation process. In this paper, we use a recently compiled database of crater cluster observations to calibrate a model of meteoroid fragmentation in Mars' atmosphere and constrain key model parameters, including the lift coefficient and fragment separation velocity, as well as meteoroid property distributions. The model distribution of dynamic meteoroid strength that produces the best match to observations has a minimum strength of 10-90 kPa, a maximum strength of 3-6 MPa and a median strength of 0.2-0.5 MPa. An important feature of the model is that individual fragmentation events are able to produce fragments with a wide range of dynamic strengths as much as 10 times stronger or weaker than the parent fragment. The calibrated model suggests that the rate of small impacts on Mars is 1.5-4 times higher than recent observation-based estimates. It also shows how impactor properties relevant to seismic wave generation, such as the total impact momentum, can be inferred from cluster characteristics.

16.
Anaesth Rep ; 10(2): e12184, 2022.
Article in English | MEDLINE | ID: mdl-35983243

ABSTRACT

Fibrodysplasia ossificans progressiva is an autosomal dominant condition that causes cervical spine fusion and ankylosis of the temporomandibular joint, resulting in anaesthetic challenges. Awake tracheal intubation with flexible bronchoscopy is recommended for general anaesthetics required by patients with this disease. This case report describes the novel approach of using dexmedetomidine sedation in combination with local anaesthesia to allow dental extraction of the fifth and seventh upper left teeth in a patient with fibrodyplasia ossificans progressive, who had a known difficult airway and profound thrombocytopenia. This procedure was not previously tolerated by the patient under local anaesthesia alone. The use of dexmedetomidine was successful in facilitating completion of the procedure with a high degree of patient satisfaction. We discuss the advantages of dexmedetomidine over other sedative agents due to its minimal effects on respiratory drive and airway muscle tone. We highlight the use of dexmedetomidine for complex cases such as this, where tracheal intubation is potentially challenging, but the procedure itself could be managed under sedation and local anaesthesia.

17.
Sci Rep ; 12(1): 5020, 2022 03 23.
Article in English | MEDLINE | ID: mdl-35322059

ABSTRACT

Kelp forests are declining in many regions globally with climatic perturbations causing shifts to alternate communities and significant ecological and economic loss. Range edge populations are often at most risk and are often only sustained through localised areas of upwelling or on deeper reefs. Here we document the loss of kelp forests (Ecklonia radiata) from the Sultanate of Oman, the only confirmed northern hemisphere population of this species. Contemporary surveys failed to find any kelp in its only known historical northern hemisphere location, Sadah on the Dhofar coast. Genetic analyses of historical herbarium specimens from Oman confirmed the species to be E. radiata and revealed the lost population contained a common CO1 haplotype found across South Africa, Australia and New Zealand suggesting it once established through rapid colonisation throughout its range. However, the Omani population also contained a haplotype that is found nowhere else in the extant southern hemisphere distribution of E. radiata. The loss of the Oman population could be due to significant increases in the Arabian Sea temperature over the past 40 years punctuated by suppression of coastal upwelling. Climate-mediated warming is threatening the persistence of temperate species and precipitating loss of unique genetic diversity at lower latitudes.


Subject(s)
Kelp , Ecosystem , Forests , Kelp/genetics , Oman , Temperature
18.
AIDS Behav ; 26(2): 350-360, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34347198

ABSTRACT

The prevention effectiveness of oral preexposure prophylaxis (PrEP) is highly dependent on medication adherence but no validated longer term PrEP adherence measures are readily available for use by primary care clinicians caring for diverse populations. We compared two self-report measures (number of doses missed in past 7 days and day-by-day past week pill taking) to results of tenofovir concentrations in dried blood spot (DBS) samples at quarterly visits over the first 12 months of PrEP use. 1420 men and women in five US community health centers enrolled in a medication adherence substudy. For 3, 6, 9 and 12 months, the respective percentages of persons with self-report vs DBS levels consistent having taken all 7 doses in the week prior were 71% (51%), 70% (47%), 71% (46%) and 69% (44%). Conversely, the percentage of participants reporting taking 0-1 doses in the week prior by self-report vs DBS drug levels at 3, 6, 9 and 12 months consistent with this level of nonadherence of 6% (9%), 5% (10%), 8% (9%), and 9% (15%). The estimated risk of low adherence (estimated 0-1 doses in the week prior) was higher for participants of Black (RR 1.60, CI 1.09-2.34) or "Other" race (RR 1.62, CI 0.99-2.65) compared with participants of White race; being a transgender female (RR 2.31, CI 1.33-4.02) compared to men who have sex with men; or enrollment at a study site with less experience in the provision of PrEP. The estimated risk of low adherence by DBS was lower for participants with a higher number of sex partners in the past 3 months and those having a bachelor's degree or higher. More work is needed to provide clinicians with measures to assess medication adherence in diverse US populations being prescribed PrEP to support its effective use in reducing HIV acquisition in individuals and at the community level.


Subject(s)
Anti-HIV Agents , HIV Infections , Pre-Exposure Prophylaxis , Sexual and Gender Minorities , Transgender Persons , Anti-HIV Agents/therapeutic use , Community Health Centers , Emtricitabine/therapeutic use , Female , HIV Infections/drug therapy , HIV Infections/prevention & control , Homosexuality, Male , Humans , Male , Medication Adherence
20.
J Exp Biol ; 224(Pt 5)2021 03 05.
Article in English | MEDLINE | ID: mdl-33674397

ABSTRACT

We quantified drinking behavior in three species of North American watersnakes: Nerodia clarkii, which is a marine or brackish water amphibious species, and Nerodiafasciata and Nerodiataxispilota, both freshwater amphibious species. All three species have relatively small and similar thresholds of dehydration (TH, approximately -4% loss of body mass) that elicit thirst and drinking of fresh water. These species have higher thirst sensitivity than several species of hydrophiine and laticaudine sea snakes, which are characterized by much lower TH (greater dehydration, -9% to <-20%). Nerodia clarkii, which is often found in coastal oceanic water, refused to drink seawater, but drank fresh water when dehydrated. In separate trials involving dehydration of N. clarkii and N. fasciata that were concurrently fed fish at regular intervals, snakes eventually refused to eat at TH of approximately -12% of original body mass, but resumed eating after they were allowed to drink fresh water and rehydrate. The drinking behaviors of Nerodia corroborate previous data on the importance of fresh water for drinking, and they complement growing evidence that dietary water does not itself mitigate dehydration in snakes. These new data increase understanding of water relationships in the context of evolutionary transitions from land to sea, and they emphasize the importance of fresh water resources in the conservation of coastal and marine species of reptiles.


Subject(s)
Colubridae , Thirst , Animals , Dehydration , Drinking , Fresh Water , Oceans and Seas , United States
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