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1.
Int J Biometeorol ; 65(12): 2099-2109, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34283273

ABSTRACT

Changes in frequency and severity of heat waves due to climate change pose a considerable challenge to livestock production systems. Although it is well known that heat stress reduces feed intake in cattle, effects of heat stress vary between animal genotypes and climatic conditions and are context specific. To derive a generic global prediction that accounts for the effects of heat stress across genotypes, management and environments, we conducted a systematic literature review and a meta-analysis to assess the relationship between dry matter intake (DMI) and the temperature-humidity index (THI), two reliable variables for the measurement of feed intake and heat stress in cattle, respectively. We analysed this relationship accounting for covariation in countries, breeds, lactation stage and parity, as well as the efficacy of various physical cooling interventions. Our findings show a significant negative correlation (r = - 0.82) between THI and DMI, with DMI reduced by 0.45 kg/day for every unit increase in THI. Although differences in the DMI-THI relationship between lactating and non-lactating cows were not significant, effects of THI on DMI varied between lactation stages. Physical cooling interventions (e.g. provision of animal shade or shelter) significantly alleviated heat stress and became increasingly important after THI 68, suggesting that this THI value could be viewed as a threshold for which cooling should be provided. Passive cooling (shading) was more effective at alleviating heat stress compared with active cooling interventions (sprinklers). Our results provide a high-level global equation for THI-DMI across studies, allowing next-users to predict effects of heat stress across environments and animal genotypes.


Subject(s)
Lactation , Milk , Animals , Cattle , Female , Heat-Shock Response , Hot Temperature , Humidity , Pregnancy , Temperature
2.
Occup Med (Lond) ; 66(6): 488-91, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27131386

ABSTRACT

BACKGROUND: Police are exposed to a wide range of stressors and this is especially true in developing countries such as Jamaica. Exposure to psychosocial stressors and use of maladaptive coping styles can result in mental ill-health. AIMS: To examine the relationship between work characteristics, coping and mental health in Jamaican police officers and to test whether work characteristics are indirectly associated with mental health outcomes through perceived job stress and job satisfaction. METHODS: Police officers from the Jamaican police force completed a questionnaire using a cross-sectional design. We analysed the data using hierarchical regression. RESULTS: The study group consisted of 134 police officers; the response rate was 94%. Negative work characteristics, lower levels of positive work factors and work support and emotion-focused coping styles were associated with increased levels of depression (F(8, 125) = 7.465, P < 0.001). Subjective feelings of anxiety were positively associated with negative work characteristics and emotion-focused coping (F(8, 125) = 7.586, P < 0.001). The relationship between work characteristics and mental health outcomes was mediated by perceived stress. Job satisfaction mediated the relationship between positive work characteristics and depression. CONCLUSIONS: Stress management and intervention programmes should address modifiable work conditions, monitor stress levels and reduce maladaptive coping.


Subject(s)
Adaptation, Psychological , Depression/etiology , Mental Health , Occupational Exposure/adverse effects , Police/psychology , Stress, Psychological/etiology , Work/psychology , Adult , Anxiety/etiology , Cross-Sectional Studies , Depressive Disorder/etiology , Female , Humans , Jamaica , Job Satisfaction , Male , Occupational Diseases/etiology , Occupational Diseases/psychology , Surveys and Questionnaires
3.
Diabet Med ; 31(9): 1069-77, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24867069

ABSTRACT

AIMS: Among people with diabetes, 10-25% will experience a foot ulcer. Research has shown that supplementation with arginine, glutamine and ß-hydroxy-ß-methylbutyrate may improve wound repair. This study tested whether such supplementation would improve healing of foot ulcers in persons with diabetes. METHODS: Along with standard of care, 270 subjects received, in a double-blinded fashion, (twice per day) either arginine, glutamine and ß-hydroxy-ß-methylbutyrate or a control drink for 16 weeks. The proportion of subjects with total wound closure and time to complete healing was assessed. In a post-hoc analysis, the interaction of serum albumin or limb perfusion, as measured by ankle-brachial index, and supplementation on healing was investigated. RESULTS: Overall, there were no group differences in wound closure or time to wound healing at week 16. However, in subjects with an albumin level of ≤ 40 g/l and/or an ankle-brachial index of < 1.0, a significantly greater proportion of subjects in the arginine, glutamine and ß-hydroxy-ß-methylbutyrate group healed at week 16 compared with control subjects (P = 0.03 and 0.008, respectively). Those with low albumin or decreased limb perfusion in the supplementation group were 1.70 (95% CI 1.04-2.79) and 1.66 (95% CI 1.15-2.38) times more likely to heal. CONCLUSIONS: While no differences in healing were identified with supplementation in non-ischaemic patients or those with normal albumin, addition of arginine, glutamine and ß-hydroxy-ß-methylbutyrate as an adjunct to standard of care may improve healing of diabetic foot ulcers in patients with risk of poor limb perfusion and/or low albumin levels. Further investigation involving arginine, glutamine and ß-hydroxy-ß-methylbutyrate in these high-risk subgroups might prove clinically valuable.


Subject(s)
Arginine/administration & dosage , Diabetic Foot/physiopathology , Dietary Supplements , Glutamine/administration & dosage , Valerates/administration & dosage , Wound Healing , Adult , Aged , Aged, 80 and over , Ankle Brachial Index , Diabetic Foot/diet therapy , Double-Blind Method , Female , Humans , Male , Middle Aged , Prospective Studies , Treatment Outcome
4.
Nutr Neurosci ; 15(4): 176-85, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22583804

ABSTRACT

RATIONALE: Chewing gum has been shown to reliably increase subjective alertness whereas the effects on attention are more variable. It has been suggested that chewing gum only enhances attention when the person has been performing a task for some time. OBJECTIVES: The current research aimed to investigate if time-on-task trends enhancing effects of chewing gum could be observed in alertness and attention during and following chewing. METHODS: Study 1 used tests of reported mood, including reported mood, and tests of attention (categoric search, focussed attention, simple reaction time, and vigilance). These tasks were performed shortly after the start of chewing. Study 2 examined effects of previous and current chewing on reported alertness and the attention tests. RESULTS: Study 1 showed that chewing gum increased reported alertness and hedonic tone and improved performance on the categoric search task. Chewing gum maintained reported alertness across sessions in study 2. In the first experimental session of study 2 gum improved categoric search performance, and during the second session gum broadened focus of attention and quickened vigilance reaction time. This effect on vigilance reaction time was moderated by time-on-task, with an initial negative effect being replaced by a positive effect. DISCUSSION: The results confirm the robust effect of chewing gum on reported alertness and show that changes in the effects of chewing gum on attention require further investigation. Future research may also determine underlying mechanisms for an alerting effect.


Subject(s)
Arousal/physiology , Attention/physiology , Chewing Gum , Mastication/physiology , Adult , Affect/physiology , Female , Humans , Male , Reaction Time/physiology , Task Performance and Analysis , Time Factors
5.
Appetite ; 59(2): 349-56, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22659382

ABSTRACT

Previous research has indicated that chewing gum enhances reported alertness, but has variable effects on attention. Demand characteristics may explain these effects. The current study investigated the effects of gum and demand characteristics on attention and reported mood over time. Participants completed measures of mood and attention, with and without chewing gum. To manipulate demand characteristics, they were told that the hypothesised effect of gum was either positive or negative, or no hypothesis was mentioned. Attitudes towards gum were assessed pre- and post-manipulation. Gum increased reported alertness; this effect was only significant for positive and neutral demand characteristics. Vigilance accuracy was reduced for chewing gum, but only in the fourth minute of the task, and gum reduced focussed attention accuracy, but only for the first 64 trials. Demand characteristics did not moderate time-on-task effects. Gum improved selective attention. A positive effect on response organisation was observed; this was significant when demand characteristics and pre-test attitudes to gum were both negative. The results suggest that demand characteristics moderate effects on self-reported alertness and response organisation, but cannot explain time-on-task effects or variable main effects on other aspects of attention.


Subject(s)
Affect/physiology , Attention/physiology , Chewing Gum , Reaction Time , Adolescent , Female , Humans , Male , Self Report , Young Adult
6.
Philos Trans R Soc Lond B Biol Sci ; 376(1817): 20190694, 2021 02.
Article in English | MEDLINE | ID: mdl-33308068

ABSTRACT

Humans spend a considerable portion of their lives engaged in 'stimulus-independent thoughts' (SIT), or mental activity that occurs independently of input from the immediate external environment. Although such SITs are, by definition, different from thoughts that are driven by stimuli in one's external environment (i.e. stimulus-dependent thoughts; SDTs), at times, the phenomenology of these two types of thought appears to be deceptively similar. But how similar are they? We address this question by comparing the content of two types of SIT (dreaming and waking SITs) with the content of SDTs. In this 7 day, smartphone-based experience-sampling procedure, participants were intermittently probed during the day and night to indicate whether their current thoughts were stimulus dependent or stimulus independent. They then responded to content-based items indexing the qualitative aspects of their experience (e.g. My thoughts were jumping from topic to topic). Results indicate substantial distinctiveness between these three types of thought: significant differences between at least two of the three mental states were found across every measured variable. Implications are discussed. This article is part of the theme issue 'Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation'.


Subject(s)
Attention/physiology , Dreams/physiology , Ecological Momentary Assessment , Female , Humans , Male , Young Adult
7.
Occup Med (Lond) ; 60(8): 635-9, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20844057

ABSTRACT

BACKGROUND: Much recent work extending the field of job characteristics to include positive aspects of work makes the implicit assumption that the absence of negative work characteristics is equivalent to the presence of positive work characteristics. AIMS: To consider the effect sizes seen at different ends of job characteristic dimensions and to compare the impact of the presence and absence of job characteristics in association with mental health and well-being outcomes. METHODS: Data from 8755 workers were analysed to compare the impacts of the presence or absence of job characteristics (job demand, extrinsic effort and social support) in associations with both positive (job satisfaction) and negative (work-related stress) outcome measures. RESULTS: Comparable presence and absence impacts were apparent for extrinsic effort in association with work-related stress. However, in the association between job demand and work-related stress, the presence of high levels of job demand had a significantly greater impact than the absence of high levels of job demand; while in the association between social support and job satisfaction, the absence of high levels of social support had a significantly greater impact than the presence of high levels of social support. CONCLUSIONS: It is not always appropriate to assume that the absence of negative aspects of the work environment is equivalent to the presence of positive aspects.


Subject(s)
Employment/psychology , Mental Health , Stress, Psychological/etiology , Work/psychology , Workload/psychology , Data Interpretation, Statistical , Female , Health Status , Health Surveys , Humans , Job Satisfaction , Male , Social Support , Stress, Psychological/epidemiology , United Kingdom/epidemiology , Work/statistics & numerical data , Workplace/organization & administration , Workplace/psychology
8.
Lab Anim ; 43(1): 1-10, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18987059

ABSTRACT

N'-ethyl-N'-nitrosourea (ENU) is a powerful germline mutagen used in conjunction with phenotype-driven screens to generate novel mouse mutants. ENU also induces genetic lesions in somatic cells and dosage requires optimization between maximum germline mutation rate versus induced sterility and tumourigenesis that compromise the welfare and fecundity of the ENU-treated males. Here, we present our experience with BALB/cAnNCrl and C57BL/6J mice in terms of the pathology induced by ENU and its impact on breeding. In both mouse strains, morbidity and mortality rises with ENU dose. In more than 75% of C57BL/6J males, morbidity and mortality were attributable to the development of malignant T-lymphoblastic lymphoma. Approximately 50% of ENU-treated BALB/cAnNCrl males develop early malignant T-lymphoblastic lymphoma, but the cohort that survives develops late-onset lung carcinoma. Within strains, the latency of these clinically important tumour(s) was not dosage-dependent, but the proportion of mice developing tumours and consequently removed from the breeding programme increased with ENU dosage. The median number of offspring per ENU-treated C57BL/6J male in standard matings with C3H/HeH females decreased with increasing dosage. The two most important underlying causes for lower male fecundity were increased infertility in the highest dosage group and reduced numbers of litters born to the remaining fertile C57BL/6J males due to a higher incidence of morbidity. These findings have allowed us to refine breeding strategy. To maximize the number of offspring from each ENU-treated male, we now rotate productive males between two cages to expose them to more females. This optimizes the number of mutation carrying offspring while reducing the number of ENU-treated males that must be generated.


Subject(s)
Animal Husbandry/methods , Ethylnitrosourea/toxicity , Fertility/drug effects , Mice, Inbred Strains , Mutagenesis , Mutagens/toxicity , Age Factors , Animal Welfare , Animals , Case-Control Studies , Dose-Response Relationship, Drug , Ethylnitrosourea/administration & dosage , Female , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mutagens/administration & dosage , Neoplasms, Experimental/chemically induced , Neoplasms, Experimental/pathology , Retrospective Studies
10.
Thorax ; 63(7): 627-34, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18250184

ABSTRACT

BACKGROUND: The mainstays of treatment for pulmonary disease caused by opportunist mycobacteria are rifampicin (R) and ethambutol (E). The role of macrolides, quinolones and immunotherapy with Mycobacterium vaccae is not clear. A trial was undertaken to compare clarithromycin (Clari) and ciprofloxacin (Cipro) as third drugs added to [corrected] 2 years of treatment with R and E for pulmonary disease caused by M avium-intracellulare (MAC), M malmoense and M xenopi (REClari and RECipro). An optional comparison of immunotherapy with M vaccae vs no immunotherapy was also performed. METHODS: Progress was monitored annually during the 2 years of treatment and for 3 years thereafter. If the patient was not improving at 1 year the regimen was supplemented by the addition of the drug not received in the original allocation of treatment. RESULTS: 371 patients (186 REClari, 185 RECipro) entered the study (170 MAC, 167 M malmoense, 34 M xenopi). All-cause mortality was high for both groups (44% REClari, 43% RECipro); for MAC it was higher with REClari than with RECipro (48% vs 29%) but for M malmoense (42% vs 56%) and M xenopi (29% vs 47%) it was higher with RECipro (p = 0.006). 3% died from their mycobacterial disease (REClari = RECipro). At the end of treatment, 4% of REClari and 10% of RECipro patients still had positive cultures. Among those with negative cultures at the end of treatment, 6% of the REClari group and 4% of the RECipro group had relapsed. At 5 years 30% of the REClari group were known to have completed treatment as allocated and to be alive and cured compared with 21% of the RECipro group (p = 0.04), but this difference was principally due to those with M malmoense (REClari 38%, RECipro 20%). Patients with MAC or M xenopi were more likely to have a poor outcome than those with M malmoense (p = 0.004), with no difference between REClari and RECipro. Overall, 20% in each group were unable to tolerate the regimen allocated, Cipro being associated with more unwanted effects than Clari (16% vs 9%, p = 0.05). No significant differences in outcomes were found between M vaccae-treated patients and those not treated with M vaccae immunotherapy. CONCLUSION: Considering all three species together, there were no differences in outcome between the REClari and RECipro groups. Immunotherapy did not improve outcome. New therapies, optimised management of co-morbid conditions and a more holistic approach must be explored in the hope of improving outcome.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Antitubercular Agents/therapeutic use , Immunotherapy/methods , Opportunistic Infections/therapy , Tuberculosis, Pulmonary/therapy , Adolescent , Adult , Aged , Ciprofloxacin/therapeutic use , Clarithromycin/therapeutic use , Drug Therapy, Combination , Ethambutol/therapeutic use , Female , Humans , Male , Middle Aged , Opportunistic Infections/mortality , Rifampin/therapeutic use , Tuberculosis, Pulmonary/mortality
11.
Parasitology ; 135(11): 1253-61, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18752708

ABSTRACT

The RhD protein which is the RHD gene product and a major component of the Rh blood group system carries the strongest blood group immunogen, the D-antigen. This antigen is absent in a significant minority of the human population (RhD-negatives) due to RHD deletion or alternation. The origin and persistence of this RhD polymorphism is an old evolutionary enigma. Before the advent of modern medicine, the carriers of the rarer allele (e.g. RhD-negative women in the population of RhD-positives or RhD-positive men in the population of RhD-negatives) were at a disadvantage as some of their children (RhD-positive children born to pre-immunized RhD-negative mothers) were at a higher risk of foetal or newborn death or health impairment from haemolytic disease. Therefore, the RhD-polymorphism should be unstable, unless the disadvantage of carriers of the locally less abundant allele is counterbalanced by, for example, higher viability of the heterozygotes. Here we demonstrated for the first time that among Toxoplasma-free subjects the RhD-negative men had faster reaction times than Rh-positive subjects and showed that heterozygous men with both the RhD plus and RhD minus alleles were protected against prolongation of reaction times caused by infection with the common protozoan parasite Toxoplasma gondii. Our results suggest that the balancing selection favouring heterozygotes could explain the origin and stability of the RhD polymorphism. Moreover, an unequal prevalence of toxoplasmosis in different countries could explain pronounced differences in frequencies of RhD-negative phenotype in geographically distinct populations.


Subject(s)
Blood Donors , Polymorphism, Genetic , Reaction Time , Rh-Hr Blood-Group System/genetics , Toxoplasma/pathogenicity , Toxoplasmosis/prevention & control , Adult , Animals , Antibodies, Protozoan/blood , Evolution, Molecular , Female , Heterozygote , Humans , Male , Military Personnel , Psychomotor Performance , Reaction Time/physiology , Rh-Hr Blood-Group System/analysis , Rh-Hr Blood-Group System/blood , Selection, Genetic , Toxoplasma/immunology , Toxoplasmosis/parasitology
12.
Oncogene ; 25(55): 7245-59, 2006 Nov 23.
Article in English | MEDLINE | ID: mdl-16751806

ABSTRACT

Deregulation of cyclin E expression and/or high levels have been reported in a variety of tumors and have been used as indicators of poor prognosis. Although the role that cyclin E plays in tumorigenesis remains unclear, there is evidence that it confers genomic instability when deregulated in cultured cells. Here we show that deregulated expression of a hyperstable allele of cyclin E in mice heterozygous for p53 synergistically increases mammary tumorigenesis more than that in mice carrying either of these markers individually. Most tumors and tumor-derived cell lines demonstrated loss of p53 heterozygosity. Furthermore, this tumor susceptibility is related to the number of times the transgene is induced indicating that it is directly attributable to the expression of the cyclin E transgene. An indirect assay indicates that loss of p53 function is an early event occurring in the mammary epithelia of midlactation mammary glands in which cyclin E is deregulated long before evidence of malignancy. These data support the hypothesis that deregulated expression of cyclin E stimulates p53 loss of heterozygosity by promoting genomic instability and provides specific evidence for this in vivo. Cyclin E deregulation and p53 loss are characteristics often observed in human breast carcinoma.


Subject(s)
Cyclin E/physiology , Genes, p53 , Loss of Heterozygosity , Mammary Glands, Animal/pathology , Mammary Neoplasms, Animal/genetics , Animals , Cell Transformation, Neoplastic , Immunohistochemistry , Mammary Neoplasms, Animal/pathology , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Transgenic
13.
J Clin Invest ; 100(2): 404-10, 1997 Jul 15.
Article in English | MEDLINE | ID: mdl-9218518

ABSTRACT

The molecular pathogenesis of pancreatic endocrine tumors is largely unknown. Such tumors are more likely to develop in individuals with the von Hippel-Lindau (VHL) syndrome. We sought to determine whether allelic loss of the recently identified VHL tumor suppressor gene on chromosome 3p25-26 occurs in the more common sporadic forms of these tumors. Allelic loss on chromosome 3p was identified in 33% of 43 patients with endocrine tumors of the pancreas. The smallest common region of allelic loss, however, centered not at the VHL locus, but rather at 3p25, centromeric to VHL. Furthermore, no mutations of the VHL gene were identified in these tumors. Loss of alleles on chromosome 3p was associated with clinically malignant disease, whereas tumors with retained 3p alleles were more likely to be benign. Thus, the VHL gene does not appear to play a pathogenic role in the development of sporadic pancreatic endocrine tumors. Instead, a locus at chromosome 3p25 may harbor a novel pancreatic endocrine tumor suppressor gene, and allelic loss of this chromosomal region may serve as a molecular marker that helps distinguish benign from clinically malignant disease.


Subject(s)
Chromosomes, Human, Pair 3/genetics , Genes, Tumor Suppressor/genetics , Ligases , Pancreatic Neoplasms/genetics , Tumor Suppressor Proteins , Ubiquitin-Protein Ligases , Adolescent , Adult , Aged , Alleles , Blotting, Southern , Chromosome Mapping , Cloning, Molecular , Female , Gene Deletion , Genetic Markers , Humans , Male , Microsatellite Repeats , Middle Aged , Polymorphism, Restriction Fragment Length , Prognosis , Proteins/genetics , Von Hippel-Lindau Tumor Suppressor Protein , von Hippel-Lindau Disease/genetics
14.
J Psychopharmacol ; 20(1): 14-23, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16204329

ABSTRACT

There are well documented acute and chronic effects of cannabis use on mental functioning. However, less is known about any effects on cognition within the context of work and everyday life. The aim of the study was to examine any association between cannabis use and cognitive performance, mood and human error at work. Cannabis users and controls completed a battery of laboratory based computer tasks measuring mood and cognitive function pre- and post-work at the start and end of a working week. They also completed daily diaries reporting their work performance. Cannabis use was associated with impairment in both cognitive function and mood, though cannabis users reported no more workplace errors than controls. Cannabis use was associated with lower alertness and slower response organization. In addition, users experienced working memory problems at the start, and psychomotor slowing and poorer episodic recall at the end of the working week. This pattern of results suggests two possible effects. First a 'hangover'-type effect which may increase with frequency of use. Second a subtle effect on cognitive function, perhaps more apparent under cognitive load and/or fatigue, which may increase with more prolonged use. The results also highlight the importance of the timing of testing within the context and routine of everyday life.


Subject(s)
Affect/drug effects , Cognition/drug effects , Marijuana Smoking/psychology , Psychomotor Performance/drug effects , Adolescent , Adult , Attention/drug effects , Female , Humans , Male , Memory/physiology , Neuropsychological Tests , Reaction Time/drug effects , Work
15.
J Psychopharmacol ; 20(1): 5-13, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16204330

ABSTRACT

There are well documented acute and chronic effects of cannabis use. However, less is known about any effects on safety within the context of work and everyday life. The aim of the study was to examine any association between cannabis use and injuries and accidents. A postal questionnaire survey was conducted among people selected at random from the electoral registers of Cardiff and Merthyr Tydfil. Cannabis use was associated with both minor injuries and accidents, particularly among those with high levels of other associated risk factors. Cannabis use was associated with a significant detrimental impact on safety. It is possible that this is linked to an amplification of other risk factors associated with accidents and injuries. This has potentially wide reaching implications particularly in the context of other work and lifestyle characteristics.


Subject(s)
Accidents/statistics & numerical data , Marijuana Abuse/psychology , Wounds and Injuries/epidemiology , Accidents, Traffic/statistics & numerical data , Adult , Cognition/physiology , Cognition Disorders/chemically induced , Cognition Disorders/epidemiology , Female , Humans , Male , Middle Aged , Odds Ratio , Regression Analysis , Surveys and Questionnaires , United Kingdom/epidemiology
17.
Cancer Res ; 56(3): 599-605, 1996 Feb 01.
Article in English | MEDLINE | ID: mdl-8564978

ABSTRACT

Only one oncogene, cyclin D1/PRAD1, has an established role in parathyroid tumorigenesis, and parathyroid tumor suppressor genes on chromosome arms 1p and 11q, which still have not been identified, have also been implicated by loss of heterozygosity analysis. To investigate whether other putative tumor suppressor genes are involved in the pathogenesis of parathyroid adenomas, we performed a more comprehensive analysis of allelic losses in these tumors. Using 39 polymorphic markers, we examined each chromosome arm, excluding the short arms of the acrocentric chromosomes. In 25 parathyroid adenomas, frequent loss of heterozygosity, in > 25% of the informative cases, was observed on chromosome arms 6q (30%), 11p (27%), and 15q (35%), in addition to previously reported 1p (30%) and 11q (38%) allelic losses. To more specifically localize the smallest shared regions of molecular genetic deletion, we examined the following chromosomes in greater detail: chromosome 6 (9 additional markers), chromosome 11 (8 additional markers), and chromosome 15 (15 additional markers). The regions most commonly deleted in these tumors were 6q22-23, 6q26-27, 11q13, 15q11-21, and 15q26-qter. All tumors with 11p loss had patterns consistent with monosomy for chromosome 11. These findings provide novel evidence for the existence of tumor suppressor genes on chromosome arms 6q and 15q that contribute commonly to the pathogenesis of parathyroid adenomas.


Subject(s)
Adenoma/genetics , Alleles , Genes, Tumor Suppressor , Parathyroid Neoplasms/genetics , Adult , Aged , Chromosome Mapping , Gene Deletion , Genome, Human , Genotype , Heterozygote , Humans , Middle Aged , Polymorphism, Genetic
18.
J Psychiatr Ment Health Nurs ; 22(10): 773-83, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26459938

ABSTRACT

ACCESSIBLE SUMMARY: What is known on the subject? Stress can impact students on mental health nurse training. This can have implications at the individual level (e.g. their own mental health) and at the level of the organization (e.g. sickness absence and attrition). What this paper adds to existing knowledge? We interviewed 12 mental health nursing students regarding the stress they experienced during training. Participants described how the academic demands can at times be unbearable during clinical placements. There were also issues with 'being a student' on some placements, with participants describing negative attitudes towards them from staff. The younger participants reported feeling overwhelmed on their initial placements and described some of the main challenges of mental health work for them. Raising concerns about the quality of care on wards was also described as particularly challenging for the students. What are the implications for practice? This paper can be useful to help training providers support mental health nursing students. Recommendations include reducing academic demands during clinical placements and extending and promoting existing support services beyond normal 9 am-5 pm working hours, even if these services are limited. Younger students could be better supported by being allocated to the more well-resourced placements in the early stages of their training. Raising awareness among staff of the tasks students can and cannot perform can help improve staff/student relations. Finally, students should be educated about the issues around raising concerns on placements to help the government's drive for a more open and transparent National Health Service (NHS). INTRODUCTION: Previous studies investigating stress in nursing students focus on general nursing students or adopt quantitative measures. PURPOSE OF STUDY: A qualitative study focusing specifically on mental health nursing students is required. METHOD: One-to-one interviews were carried out with mental health nursing students (n = 12). Data were thematically analysed. RESULTS: Participants reported unreasonable demands during clinical blocks, and described how control/support is lowest on placements with staff shortages. Negative attitudes towards students from staff and related issues were also discussed. Younger participants described struggling with mental health work during the early stages of training. DISCUSSION: Training providers should strive to provide adequate support to students to help them manage stress during training. Implications for practice Academic demands should be reasonable during clinical blocks and support services outside normal working hours should be available for students, even if these are limited in scope. Greater consideration to the allocation of placements for younger students in the mental health branch could be helpful. Furthermore, staff on placements should be aware of the tasks students can and cannot perform, to help improve staff/student relations. Educating students on the issues of raising concerns can help the government's drive for a more open and transparent National Health Service (NHS).


Subject(s)
Education, Nursing, Baccalaureate , Psychiatric Nursing/education , Stress, Psychological/psychology , Students, Nursing/psychology , Adult , Female , Humans , Interview, Psychological , Male , Nursing Education Research , Qualitative Research , Young Adult
19.
J Bone Miner Res ; 12(9): 1330-4, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9286748

ABSTRACT

Loss of chromosome arm 1p DNA is the most common molecular defect thus far observed in human parathyroid adenomas, suggesting that 1p is the location of a putative tumor suppressor gene (or genes) whose inactivation contributes frequently to parathyroid tumorigenesis. To narrow the genomic location of this tumor suppressor gene, we analyzed 25 sporadic parathyroid adenomas for allelic loss of polymorphic DNA loci on chromosome 1 using 11 microsatellite markers not previously scored for this set of tumors. Allelic loss on chromosome arm 1p DNA was observed in 8 of 25 adenomas. Marker deletion patterns showed some complexity, with the regions most commonly deleted in these tumors being 1p36 and 1p35-p31. The 1p35-p31 region contains an excellent candidate tumor suppressor gene, p18, whose product is a cell cycle regulator that inhibits the cyclin D1-associated kinase CDK6. Given that cyclin D1 is a parathyroid oncogene, inactivation of an inhibitor of cyclin D1 function, like p18, might also cause excessive parathyroid growth. To examine the involvement of p18 in parathyroid tumorigenesis, we analyzed 25 parathyroid adenomas for mutations of the p18 coding exons by single strand conformational polymorphism analysis and sequencing. No point mutations were found in any of the 25 adenomas. These observations indicate that inactivating mutation of the p18 gene occurs uncommonly, if at all, in parathyroid adenomas. In addition, the data raise the important possibility that more than a single tumor suppressor gene on 1p could contribute to parathyroid neoplasia.


Subject(s)
Adenoma/genetics , Chromosomes, Human, Pair 1 , Cyclin-Dependent Kinases/antagonists & inhibitors , Enzyme Inhibitors , Genes, Tumor Suppressor , Parathyroid Neoplasms/genetics , Alleles , Chromosome Banding , Humans , Microsatellite Repeats , Polymorphism, Single-Stranded Conformational
20.
J Clin Endocrinol Metab ; 81(10): 3663-7, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8855819

ABSTRACT

Rearrangement and overexpression of the PRAD1/cyclin D1 oncogene, a cell cycle regulator, have been implicated in the pathogenesis of a subset of parathyroid adenomas. Recently, two cell cycle regulators that inhibit the cyclin D1-associated kinases cdk4 and cdk6 have been identified: p16 and p15, the products of the INK4A (also known as CDKN2, MTS1) and INK4B (also known as MTS2) putative tumor suppressor genes located on 9p21. Because inactivation of the p16 or p15 genes might be expected to result in oncogenic consequences similar to those from cyclin D1 overexpression, we examined 25 parathyroid adenomas for 1) allelic loss of polymorphic DNA loci on chromosome arm 9p, 2) homozygous deletions of the p16 and p15 genes by Southern blot analysis, and 3) mutations of the p16 and p15 genes by single strand conformational polymorphism analysis. Heterozygous allelic loss at 9p was observed in 4 of 25 adenomas (16%); their smallest shared region of deletion was 9p21-pter, which includes both the p16 and p15 genes. However, single strand conformational polymorphism analysis of all 3 exons of the p16 gene and both exons of the p15 gene failed to demonstrate mutation in any of the 25 cases, and homozygous deletions of the p16 and p15 genes, which are present in some human cancers, were not found in any parathyroid tumors. These observations indicate that inactivating mutations or homozygous deletions of the p16 and p15 genes occur uncommonly, if ever, in parathyroid adenomas; however, loss of a different tumor suppressor gene (or genes) on 9p appears to contribute to the pathogenesis of a significant percentage of these tumors.


Subject(s)
Carrier Proteins/genetics , Cell Cycle Proteins , Chromosomes, Human, Pair 9 , DNA/chemistry , Enzyme Inhibitors , Parathyroid Neoplasms/genetics , Tumor Suppressor Proteins , Base Sequence , Blotting, Southern , Cyclin-Dependent Kinase Inhibitor p15 , Cyclin-Dependent Kinase Inhibitor p16 , Gene Deletion , Humans , Molecular Sequence Data , Mutation , Polymorphism, Single-Stranded Conformational , Protein Kinase Inhibitors
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