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1.
J Med Libr Assoc ; 112(1): 5-12, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38911525

ABSTRACT

Objective: While several studies have examined the effectiveness of librarian interactions with clinicians and impact of librarians on patient care, no studies have explored a library's effects on population care. The goal of this study was to investigate the library's impact on both patient and population care. Methods: Using a sequential exploratory mixed-methods design, we first interviewed a small set of clinicians and researchers active in patient and population care. Based on the themes that we discovered through coding the interviews, we created a survey that was sent to faculty in the health sciences and the health system. Results: We collected data from a representative sample of our population. We discovered that all respondents value the library and informationists, using our services most for teaching, publishing, presenting, and professional development. Conclusion: We now have data to support our value to our population and to show where we can do more work to improve the use of our services. Our study shows the value of doing a mixed-methods sequential exploration in which themes that are important to our user community were identified prior to launching a large-scale survey.


Subject(s)
Librarians , Libraries, Medical , Humans , Libraries, Medical/organization & administration , Library Services/organization & administration , Library Services/statistics & numerical data , Patient Care , Surveys and Questionnaires , Female
2.
Health Equity ; 6(1): 750-766, 2022.
Article in English | MEDLINE | ID: mdl-36225656

ABSTRACT

Introduction: Type 2 diabetes (T2D) is one of the leading causes of death among Asian Americans. Despite being a culturally diverse racial group with differences in history, language, religion, and values, Asian Americans are often viewed as a monolith. With the high prevalence rate of T2D, a careful examination of self-management interventions across Asian Americans is needed to develop effective and culturally sensitive interventions. Objective: To describe existing literature by examining study characteristics, different intervention components, and outcome measures of various T2D interventions among Asian Americans. Methods: Using Arksey and O'Malley's framework to ground this review, six online databases were used to identify studies. Results: A total of 18 publications were included. Thirteen studies were published after 2013, with 44% and 22% of these studies focused on Chinese Americans and Korean Americans. We found a lack of geographic diversity in the location of the studies. Majority of the participants were females. Most of the interventions were implemented in person. Licensed health care providers were the most common interventionists, with a number of studies using community health workers. Outcome measures focused on three key areas: physiological, psychosocial and behavioral, and program-related outcomes. Many of the studies measured changes in HbA1C, self-efficacy, distress, depression, and quality of life. Overall, we saw improvements in physiological measures in most of the studies. For example, majority of the studies showed a decline in the participants' HbA1C. Most studies showed an increase or improvement in healthy behaviors. Studies that measured efficacy, knowledge, attitude, motivation, quality of life, or general health showed improvement from baseline. All the studies that measured distress or depression showed a reduction of symptoms postintervention. Conclusion: Overall, we found that culturally tailored interventions that focus on specific Asian American subpopulations saw an improvement in physiological, psychosocial, or behavioral measures. There were several gaps in the existing T2D self-management programs or interventions among Asian Americans studied in the United States. Based on our analysis, we recommend when designing or implementing self-management interventions among Asian Americans, considerations should be made for targeted recruitment for understudied Asian American subgroups, gender, and location.

3.
J Gen Intern Med ; 37(2): 375-389, 2022 02.
Article in English | MEDLINE | ID: mdl-34027605

ABSTRACT

BACKGROUND: Given increasing numbers of people experiencing transitions in health insurance due to declines in employer-sponsored insurance and changes in health policy, the understanding and application of health insurance terms and concepts (health insurance literacy) may be important for navigating use of health care. The study objective was to systematically review evidence on the relationship between health insurance literacy and health care utilization. METHODS: Medline, SCOPUS, Web of Science, CINAHL, PsychInfo, Cochrane Library, and reference lists of published literature were searched in August 2019. Quantitative, qualitative, and intervention studies that assessed the association of health insurance literacy as the exposure and health care utilization as the outcome were identified, without language or date restrictions. Outcomes were independently assessed by 2-3 reviewers. RESULTS: Twenty-one studies including a total of 62,416 subjects met inclusion criteria: three interventional trials, two mixed-methods studies, and sixteen cross-sectional studies. Ten of thirteen preventive care studies suggested that higher health insurance literacy was associated with greater utilization of primary care and other preventive services. Eight of nine studies of care avoidance demonstrated that individuals with lower health insurance literacy were more likely to delay or avoid care. A few studies had mixed results regarding the utilization of emergency department, inpatient, and surgical care. DISCUSSION: The emerging literature in this area suggests that health insurance literacy is an important factor that can enable effective utilization of health care, including primary care and preventive services. However, the literature is limited by a paucity of studies using validated tools that broadly measure health insurance literacy (rather than testing knowledge of specific covered services). Improving health insurance literacy of the general public and increasing plain language communication of health insurance plan features at the point of health care navigation may encourage more effective and cost-conscious utilization.


Subject(s)
Health Literacy , Insurance, Health , Cross-Sectional Studies , Health Literacy/methods , Humans , Patient Acceptance of Health Care , Preventive Health Services
4.
Med Care Res Rev ; 79(2): 175-197, 2022 04.
Article in English | MEDLINE | ID: mdl-34157906

ABSTRACT

Consumer cost-sharing has been shown to diminish utilization of preventive services. Recent efforts, including provisions within the Affordable Care Act, have sought to increase use of preventive care through elimination of cost-sharing for clinically indicated services. We conducted a rapid review of the literature to determine the impact of cost-share elimination on utilization of preventive services. Searches were conducted in PubMed, Scopus, and CINAHL Complete databases as well as in grey literature. A total of 35 articles were included in qualitative synthesis and findings were summarized for three clinical service categories: cancer screenings, contraceptives, and additional services. Impacts of cost-sharing elimination varied depending on clinical service, with a majority of findings showing increases in use. Studies that included socioeconomic status reported that those who were financially vulnerable incurred substantial increases in utilization. Future investigations on additional clinical services are warranted as is research to better elucidate populations who most benefit from cost-sharing elimination.


Subject(s)
Cost Sharing , Patient Protection and Affordable Care Act , Databases, Factual , Early Detection of Cancer , Humans , Preventive Health Services , United States
5.
Am J Prev Med ; 61(4): e203-e210, 2021 10.
Article in English | MEDLINE | ID: mdl-34175172

ABSTRACT

CONTEXT: Peer providers with lived experiences of mental health and substance use are a growing component of the workforce responsible for the prevention and treatment of behavioral health disorders. This systematic literature review aims to better define the roles of peers and their unique contributions to behavioral health care. EVIDENCE ACQUISITION: Researchers searched MEDLINE, CINAHL Complete, PsycINFO, Cochrane Central, and Scopus databases for studies published between January 1, 2013 and April 3, 2020. Studies were included if they (1) were experimental or observational studies, (2) included an adult population of people with a behavioral health disorder, and (3) used paid peer providers in addition to traditional behavioral health services. Researchers extracted sample demographics, intervention characteristics, outcome data, and significant associations from studies that met inclusion criteria and assessed the trends in these data in May 2020. EVIDENCE SYNTHESIS: A total of 23 articles assessing peer-provided services were included. Peers were employed most frequently in mental healthcare roles in the Department of Veterans Affairs, hospital, and community health facilities. A total of 14 studies observed significant clinical improvements in participants' social functioning, quality of life, patient activation, and behavioral health. A majority of studies involved the supervision of peers and required peers to have completed training in service delivery. CONCLUSIONS: Peers are effective providers of behavioral health treatment and relapse prevention services who encourage recovery through resilience building, empowerment, and self-advocacy. There remains a need for more evidence-based interventions on the efficacy of peers in substance use disorder treatment and the impact of formalized certification and training opportunities.


Subject(s)
Health Workforce , Quality of Life , Humans , United States
6.
Sex Med Rev ; 9(2): 244-266, 2021 04.
Article in English | MEDLINE | ID: mdl-33608247

ABSTRACT

INTRODUCTION: As most adults with spina bifida are either sexually active or interested in becoming sexually active, providers should understand how spina bifida impacts sexual function and options for treatment. OBJECTIVES: The objective of this study is to summarize the current literature describing how features of spina bifida impact sexual function in men and women, effective available treatment options for sexual dysfunction, and to identify research gaps. METHODS: Searches were conducted in PubMed, CINAHL Complete, PsychInfo, Cochrane Central, Scopus, and Web of Science Core Collection databases using keywords related to spina bifida and sexual function. 34 primary research studies were included. RESULTS: Most men (56-96%) can achieve an erection, although it may be insufficient for penetration. Although 50-88% ejaculate, it is often dripping, retrograde, or insensate. Twenty percent to 67% achieve orgasm. Generally, men with lower lesions and intact sacral reflexes have better outcomes, although some men with all levels of lesion report good function. Sildenafil is efficacious at treating erectile dysfunction for most men. The "TO-MAXimize sensation, sexuality, and quality of life" procedure may improve sexual function in selected men with low-level lesions. Female sexual function and treatment is less well understood. Women may experience decreased arousal, difficulties with orgasm, and pain. No treatment has been studied in women. Bowel and bladder incontinence during intercourse appears to be bothersome to men and women. Although both men and women have diminished sexual satisfaction, their sexual desire appears to be least impacted. Present studies are limited by studies' small, heterogeneous populations, the misuse of validated questionnaires in the sexually inactive population, and the lack of a validated questionnaire specific to people with spina bifida. CONCLUSIONS: Spina bifida impacts the sexual function of both men and women. Future studies should seek a better understanding of female sexual function and treatment, use validated questionnaires appropriately, and ultimately create a validated sexual function questionnaire specific to this population. Streur CS, Corona L, Smith JE, et al. Sexual Function of Men and Women With Spina Bifida: A Scoping Literature Review. Sex Med Rev 2021;9:244-266.


Subject(s)
Sexual Dysfunction, Physiological , Spinal Dysraphism , Adult , Female , Humans , Male , Quality of Life , Sexual Behavior , Sexual Dysfunction, Physiological/etiology , Sexual Dysfunction, Physiological/therapy , Sexuality , Spinal Dysraphism/complications
7.
Med Ref Serv Q ; 38(3): 260-270, 2019.
Article in English | MEDLINE | ID: mdl-31379282

ABSTRACT

Informationists at the Taubman Health Sciences Library, University of Michigan, formed a research impact consultation and education initiative in early 2017 to increase engagement with the health sciences community around the informed, responsible use of a range of citation and alternative metrics and associated tools. So far, the Research Impact Core has primarily entailed developing training content and cultivating partnerships related to publication metrics and associated best practices. This article reports on progress from the first two years of the Research Impact Core, including a snapshot of information session registrants, and a broader discussion of collaborative partnerships around research impact in the health sciences and library system.


Subject(s)
Biomedical Research/organization & administration , Data Collection/methods , Intersectoral Collaboration , Libraries, Medical/organization & administration , Humans , Michigan
8.
Hepatology ; 67(6): 2375-2383, 2018 06.
Article in English | MEDLINE | ID: mdl-29272043

ABSTRACT

Patients with cirrhosis seek improvement in their symptoms, functioning, quality of life, and satisfaction with the care they receive. However, these patient-reported outcomes (PROs) are not routinely measured for clinical care, research, or quality improvement. The members of the American Association for the Study of Liver Diseases Practice Metrics Committee, charged with developing quality indicators for clinical practice, performed a scoping review of PROs in cirrhosis. The aim is to synthesize a comprehensive set of PROs for inclusion into a standard patient-centered outcome set. We searched Medline, Embase, the Cumulative Index to Nursing and Allied Health Literature, PsycINFO, and the Cochrane Trial Library since inception, with final searches run between April 20 and June 1, 2017. Studies were included if they reported the construction and/or validation of a PRO instrument for patients with cirrhosis or if they assessed the clinical (case-mix) variables determining responses to established PRO scales. Eleven studies were selected that yielded 259 items specific to patients with cirrhosis. After removing duplicates, 152 unique items were isolated. These items were consolidated into seven domains: physical symptoms, physical function, mental health, general function, cognition, social life, and satisfaction with care. The seven domains included 52 subdomains (e.g., physical domain, abdominal pain subdomain). Twelve variables were identified that independently modified established PRO scales. These included clinical factors (severity of liver disease and its complications, medication burden, and comorbidities), specific PROs (cramps, pruritis), and surrogate outcome measures (falls, hospitalization). CONCLUSION: This scoping review identified and categorized a large existing set of PRO concepts that matter to patients with cirrhosis; these outcomes may now be translated into usable measures both for the assessment of the quality of cirrhosis care in clinical practice and to perform research from the patient's perspective. (Hepatology 2018;67:2375-2383).


Subject(s)
Liver Cirrhosis/therapy , Patient Reported Outcome Measures , Humans
9.
Vet Parasitol Reg Stud Reports ; 14: 191-199, 2018 12.
Article in English | MEDLINE | ID: mdl-31014729

ABSTRACT

Toxoplasmosis is a zoonotic disease of worldwide distribution. The parasite exhibits strong geographical patterns of strain variation with contrasting high levels of diversity across South America and restricted variation across North America. Little is known about the diversity of strains in the transitional area between the two continents. Here we present data on the prevalance and diversity of Toxoplasma gondii in the Yucatan peninsula of Mexico, through a study in commercially reared pigs. A survey of 12 farms found evidence of circulating T. gondii DNA in 125 of 632 blood samples (19.8%, CI: 16.7%-23%). In addition, 46 tongue samples were collected from culled animals and 16 of these were positive for T. gondii DNA and 3 were positive in mouse bioassay. PCR-sequencing was used to generate genotyping data from blood and tissue samples. Four loci (SAG1, 2, 3 and GRA6) were reliably amplified and revealed a high diversity among Yucatan strains with evidence of recombination and novel alleles. Sequencing data from the four loci was achieved in eight samples each of which had a different genotype. The predominant allelic type was atypical, in relation to the dominant strain types (I, II, III), the number of allelic variants being 27 (I, II-III, u-1-25), 20 (I, III, u1-18), 6 (I, III, u1-4) and 11 (I, II, u1-9) for the SAG1, SAG2, SAG3 and GRA6 loci respectively. Phylogenetic analysis showed that T. gondii strains from Yucatan shared alleles with strains originating from both North and South America. Our findings are consistent with data from other regions of Central America and suggest the genetic population structure of the parasite, with significant levels of allelic variation and recombination, constitutes a reservoir from which new strains may emerge. Positive bioassay results (7.5%) indicate that consumption of undercooked pork could be a potential T. gondii infection risk to humans.


Subject(s)
Disease Reservoirs/veterinary , Swine Diseases/parasitology , Swine/parasitology , Toxoplasma/genetics , Toxoplasmosis, Animal/epidemiology , Alleles , Animals , DNA, Protozoan/genetics , Disease Reservoirs/parasitology , Farms , Female , Genetic Variation , Genotype , Livestock/parasitology , Male , Mexico/epidemiology , Mice , Phylogeny , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Rats/parasitology , Recombination, Genetic , Swine Diseases/epidemiology , Tongue/parasitology
10.
Surg Obes Relat Dis ; 13(10): 1768-1779, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28958402

ABSTRACT

Bariatric surgery has been performed on adolescents since the 1970s, but little is known about the guidance offered to providers in recommendation documents published in the United States. A systematic review was conducted to generate a complete record of all US recommendation documents and describe variability across the documents. This study had 3 aims: to identify the developers, examine selection criteria, and document reasons why developers have recommended this intervention for adolescents. Four databases (MEDLINE, National Guidelines Clearinghouse, Trip, and Embase) ertr searched, followed by a hand search. Documents were eligible for inclusion if they satisfied 5 criteria: written in the English language; developed and published by a US organization; comprised a clinical practice guideline, position statement, or consensus statement; offered a minimum 1-sentence recommendation on bariatric surgery for the treatment of obesity or related co-morbidities; and offered a minimum 1-sentence recommendation on bariatric surgery for children, adolescents, or both. No date limits were applied. Sixteen recommendation documents published between 1991 and 2013 met our inclusion criteria: 10 clinical practice guidelines, 4 position statements, and 2 consensus statements. Nine were produced by medical organizations, 3 by surgical organizations, and 4 by public health/governmental bodies. One document recommended against bariatric surgery for minors, and 15 endorsed the intervention for this population. Body mass index (a measure of obesity calculated by dividing weight in kilograms by the square of height in meters) thresholds were the selection criteria most often provided. Minimum age varied widely. Of the 15 endorsing documents, 10 provided a reason for performing bariatric surgery on minors, most often to treat obesity-related co-morbidities that threaten the health of the adolescent. We make 3 suggestions to improve the quality of future recommendation documents.


Subject(s)
Bariatric Surgery , Pediatric Obesity/surgery , Adolescent , Body Mass Index , Consensus , Documentation , Humans , Medical Records , Practice Guidelines as Topic
11.
J Med Libr Assoc ; 105(3): 268-275, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28670216

ABSTRACT

OBJECTIVE: The project identified a set of core competencies for librarians who are involved in systematic reviews. METHODS: A team of seven informationists with broad systematic review experience examined existing systematic review standards, conducted a literature search, and used their own expertise to identify core competencies and skills that are necessary to undertake various roles in systematic review projects. RESULTS: The team identified a total of six competencies for librarian involvement in systematic reviews: "Systematic review foundations," "Process management and communication," "Research methodology," "Comprehensive searching," "Data management," and "Reporting." Within each competency are the associated skills and knowledge pieces (indicators). Competence can be measured using an adaptation of Miller's Pyramid for Clinical Assessment, either through self-assessment or identification of formal assessment instruments. CONCLUSIONS: The Systematic Review Competencies Framework provides a standards-based, flexible way for librarians and organizations to identify areas of competence and areas in need of development to build capacity for systematic review integration. The framework can be used to identify or develop appropriate assessment tools and to target skill development opportunities.


Subject(s)
Librarians , Professional Competence , Review Literature as Topic , Communication , Humans , Search Engine
12.
Med Ref Serv Q ; 35(1): 52-63, 2016.
Article in English | MEDLINE | ID: mdl-26794196

ABSTRACT

This article describes the collaboration between the University of Michigan's M-Library and the University of Michigan Medical School's Office of Research in developing a comprehensive online guide and consultation service. The guide was designed to assist researchers in finding available funding from both internal and external sources and was based on the results of a survey distributed by the Office of Research. Because many of the respondents were unaware of internal funding programs and needed more information on resources external to the university as well, the guide included information on both possibilities in an easy-to-use format that researchers use independently without needing further instruction, although personal consultation was also offered when necessary.


Subject(s)
Cooperative Behavior , Financial Management , Research/economics , Universities , Michigan , Organizational Case Studies
13.
Parasitology ; 142(11): 1415-21, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26144268

ABSTRACT

In wild rabbits (Oryctolagus cuniculus) on an estate in Perthshire, central Scotland, the seroprevalence of Toxoplasma gondii was 18/548 (3·3%). The wild rabbit could be a T. gondii reservoir and it has potential value as a sentinel of T. gondii in environmental substrates. Toxoplasma gondii was associated with female sex (P < 0·001) and with relatively heavy infections by Eimeria stiedae (P = 0·036). It was not associated with the intensity of coccidial oocysts, the severity of myxomatosis caused by the virus Myxomatosis cuniculi, the intensity of roundworm eggs, the year or season, rabbit age or distance from farm buildings. Coinfections could have been affected by gestational down regulation of type 1 T helper cells. A sudden influx or release of T. gondii oocysts might have occurred. This is the first report of T. gondii in any wild herbivore in Scotland and also the first report of lapine T. gondii as a coinfection with E. stiedae, M. cuniculi and helminths.


Subject(s)
Coccidiosis/veterinary , Coinfection , Eimeria/isolation & purification , Rabbits , Toxoplasma/immunology , Toxoplasmosis, Animal/epidemiology , Animals , Antibodies, Protozoan/immunology , Coccidiosis/complications , Female , Helminthiasis, Animal/complications , Myxoma virus/isolation & purification , Myxomatosis, Infectious/complications , Oocysts , Rabbits/parasitology , Scotland/epidemiology , Seroepidemiologic Studies , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/parasitology
14.
J Med Libr Assoc ; 103(2): 69-73, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25918484

ABSTRACT

OBJECTIVE: The researchers used the flipped classroom model to develop and conduct a systematic review course for librarians. SETTING: The research took place at an academic health sciences library. METHOD: A team of informationists developed and conducted a pilot course. Assessment informed changes to both course components; a second course addressed gaps in the pilot. MAIN RESULTS: Both the pilot and subsequent course received positive reviews. Changes based on assessment data will inform future iterations. CONCLUSION: The flipped classroom model can be successful in developing and implementing a course that is well rated by students.


Subject(s)
Education, Continuing , Library Science/education , Review Literature as Topic , Curriculum , Education, Continuing/methods , Humans
15.
PLoS One ; 9(7): e95122, 2014.
Article in English | MEDLINE | ID: mdl-24988478

ABSTRACT

Symbionts can substantially affect the evolution and ecology of their hosts. The investigation of the tissue-specific distribution of symbionts (tissue tropism) can provide important insight into host-symbiont interactions. Among other things, it can help to discern the importance of specific transmission routes and potential phenotypic effects. The intracellular bacterial symbiont Wolbachia has been described as the greatest ever panzootic, due to the wide array of arthropods that it infects. Being primarily vertically transmitted, it is expected that the transmission of Wolbachia would be enhanced by focusing infection in the reproductive tissues. In social insect hosts, this tropism would logically extend to reproductive rather than sterile castes, since the latter constitute a dead-end for vertically transmission. Here, we show that Wolbachia are not focused on reproductive tissues of eusocial insects, and that non-reproductive tissues of queens and workers of the ant Acromyrmex echinatior, harbour substantial infections. In particular, the comparatively high intensities of Wolbachia in the haemolymph, fat body, and faeces, suggest potential for horizontal transmission via parasitoids and the faecal-oral route, or a role for Wolbachia modulating the immune response of this host. It may be that somatic tissues and castes are not the evolutionary dead-end for Wolbachia that is commonly thought.


Subject(s)
Ants/microbiology , Host-Pathogen Interactions/physiology , Symbiosis , Wolbachia/physiology , Animals , Fat Body/microbiology , Feces/microbiology , Female , Germ Cells/microbiology , Hemolymph/microbiology , Ovary/microbiology
17.
J Prim Care Community Health ; 5(1): 67-73, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-23799678

ABSTRACT

OBJECTIVE: Despite the prevailing consensus as to its value, the adoption of integrated care models is not widespread. Thus, the objective of this article it to examine the barriers to the adoption of depression and primary care models in the United States. METHODS: A literature search focused on peer-reviewed journal literature in Medline and PsycInfo. The search strategy focused on barriers to integrated mental health care services in primary care, and was based on previously existing searches. The search included: MeSH terms combined with targeted keywords; iterative citation searches in Scopus; searches for grey literature (literature not traditionally indexed by commercial publishers) in Google and organization websites, examination of reference lists, and discussions with researchers. FINDINGS: Integration of depression care and primary care faces multiple barriers. Patients and families face numerous barriers, linked inextricably to create challenges not easily remedied by any one party, including the following: vulnerable populations with special needs, patient and family factors, medical and mental health comorbidities, provider supply and culture, financing and costs, and organizational issues. CONCLUSIONS: An analysis of barriers impeding integration of depression and primary care presents information for future implementation of services.


Subject(s)
Delivery of Health Care, Integrated/organization & administration , Depressive Disorder/therapy , Health Services Accessibility/standards , Mental Health Services/organization & administration , Primary Health Care/organization & administration , Humans , United States
18.
Appl Environ Microbiol ; 79(1): 385-8, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23087031

ABSTRACT

We designed fluorescence in situ hybridization probes for two distinct microsporidian clades and demonstrated their application in detecting, respectively, Nosema/Vairimorpha and Dictyoceola species. We used them to study the vertical transmission of two microsporidia infecting the amphipod Gammarus duebeni.


Subject(s)
Amphipoda/microbiology , In Situ Hybridization, Fluorescence/methods , Microsporidia/isolation & purification , Animals , Microsporidia/genetics , Oligonucleotide Probes/genetics
19.
J Invertebr Pathol ; 112(2): 146-51, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23207223

ABSTRACT

Feminizing parasites enhance their vertical transmission to the host offspring by converting genetic male hosts into phenotypic females. Crustacea are the only invertebrates where sexual differentiation is controlled by a specialised endocrine organ, the androgenic gland, rather than by the gonads. We showed that a feminizing microsporidian Microsporidium sp. inhibits androgenic gland differentiation. We investigated the effect of Microsporidium sp. and a second feminizing microsporidium, Nosema granulosis, on the masculinizing function of the androgenic gland in Gammarus duebeni. Androgenic gland implants had a masculinizing effect on the sexual characteristics and sexual behaviour of recipient female hosts, reflecting the masculinizing function of the androgenic gland. Individuals that had received androgenic glands showed changed morphology in comparison with controls; they were bigger overall, they lost their oostegite marginal setae, developed calceoli and acquired a male-like behaviour. This effect was observed in uninfected females, as well as in females infected with the Microsporidium sp. The masculinizing effect of androgenic gland implants was smaller in N. granulosis infected individuals. N. granulosis and Microsporidium sp. fall into distinct clades of the Microspora. It appears that these divergent parasites both act by inhibiting the development of the androgenic gland. However, they differ in their ability to inhibit the host's response to the hormone that controls male sexual differentiation.


Subject(s)
Amphipoda/microbiology , Exocrine Glands/microbiology , Feminization/physiopathology , Host-Parasite Interactions/physiology , Microsporidia/physiology , Sex Differentiation/physiology , Androgens/metabolism , Animals , Exocrine Glands/metabolism , Female , Male , Sex Determination Processes/physiology
20.
PLoS One ; 7(1): e30641, 2012.
Article in English | MEDLINE | ID: mdl-22347356

ABSTRACT

Many pollinator populations are declining, with large economic and ecological implications. Parasites are known to be an important factor in the some of the population declines of honey bees and bumblebees, but little is known about the parasites afflicting most other pollinators, or the extent of interspecific transmission or vectoring of parasites. Here we carry out a preliminary screening of pollinators (honey bees, five species of bumblebee, three species of wasp, four species of hoverfly and three genera of other bees) in the UK for parasites. We used molecular methods to screen for six honey bee viruses, Ascosphaera fungi, Microsporidia, and Wolbachia intracellular bacteria. We aimed simply to detect the presence of the parasites, encompassing vectoring as well as actual infections. Many pollinators of all types were positive for Ascosphaera fungi, while Microsporidia were rarer, being most frequently found in bumblebees. We also detected that most pollinators were positive for Wolbachia, most probably indicating infection with this intracellular symbiont, and raising the possibility that it may be an important factor in influencing host sex ratios or fitness in a diversity of pollinators. Importantly, we found that about a third of bumblebees (Bombus pascuorum and Bombus terrestris) and a third of wasps (Vespula vulgaris), as well as all honey bees, were positive for deformed wing virus, but that this virus was not present in other pollinators. Deformed wing virus therefore does not appear to be a general parasite of pollinators, but does interact significantly with at least three species of bumblebee and wasp. Further work is needed to establish the identity of some of the parasites, their spatiotemporal variation, and whether they are infecting the various pollinator species or being vectored. However, these results provide a first insight into the diversity, and potential exchange, of parasites in pollinator communities.


Subject(s)
Bees/parasitology , Hymenoptera/parasitology , Parasites/pathogenicity , Pollination , Wasps/parasitology , Animals , Bees/virology , DNA, Viral/genetics , Hymenoptera/virology , Insect Viruses/genetics , Insect Viruses/isolation & purification , Polymerase Chain Reaction , Wasps/virology
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