Identification of an expanded population of activated CD4(+) CD25(+) T cells expressing CD45RO and IL-7R in kidney transplant recipients

Recent studies have shown that CD4+ CD25+ T cells belong to two functionally different T lymphocytes, i.e. regulatory T cells (Treg) or activated T cells (Tact), which can be distinguished based on the expression of CD45RO and IL-7R: Treg (FoxP3+) are CD45RO+ IL-7R- , whereas Tact (FoxP3- ) are CD45RO+ IL- 7R+. In order to determine if a CD4+ CD25+ CD45RO+ IL-7R+ activated T cell population might be identified in kidney transplant recipients, we studied 27 healthy subjects (HS) and 23 kidney recipients, of whom 17 had stable graft function under standard immunosuppression (IS), 5 had biopsy-proven chronic humoral rejection (CHR), and one was a stable "tolerant" patient who had discontinued IS for more than 2 years. Phenotypical analysis by flow cytometry and functional assays by MLR were performed. Overall, the Tact population was found to be significantly increased in 87% of the transplant recipients (mean: 18.8±10.1% of CD4+ CD25+ T cells) compared to HS (mean: 4.5±2.0%; P<0.0001). In the 5 patients with CHR, this Tact population was highly expanded (31.3±9.3%; P<0.0001), whereas it was comparable to HS in the "tolerant" recipient (4.7%). Intermediate levels (16.0±6.9%; P<0.0001) were found in the 17 stable recipients. In CHR, the proliferative capacity of the Tact population was found to be 5-fold higher when stimulated by irradiated donor PBMC as compared to a stimulation by irradiated 3rd party PBMC. After kidney transplantation, an expanded circulating CD4+ CD25+ T cell population characterized by the expression of CD45RO and IL-7R was found in most recipients, particularly in those with CHR. In a patient with long-term operational tolerance, this Tact population was similar to HS. Measuring circulating Tact may become a useful monitoring tool after transplantation.

Thermal Constant of an Experimental Population of Muscina stabulans (Fallén 1817) (Diptera:Muscidae) in the Laboratory

A study was conducted to investigate the thermal constant in an experimental population of Muscina stabulans (Fallén 1817). A natural population was obtained from a livestock and their F1 generations were maintained at four constant temperatures (16°C, 20°C, 26°C and 31°C). The thermal constant was calculated by the hyperbole method using the base temperature, tb = 4.4°C and the thermal constant K = 35.3 GD. Ricker's geometric regression, considering tb = 7.8°C and K = 28.9 GD was also calculated.

Compliance with dietary recommendations in the population of Geneva, Switzerland: a ten-year trend study (1999-2009)

Introduction: There is little information regarding compliance with dietary recommendations in Switzerland. Objectives: To assess the trends in compliance with dietary recommendations in the Geneva population for period 1999 - 2009. Methods: Ten cross-sectional, population-based surveys (Bus Santé study). Dietary intake was assessed using a self-administered, validated semi quantitative Food Frequency Questionnaire. Compliance with the Swiss Society for Nutrition recommendations for nutrient intake was assessed. In all 9320 participants aged 35 to 75 years (50% women) were included. Trends were assessed by logistic regression adjusting for age, smoking stats, education and nationality, using survey year as the independent variable. Results: After excluding participants with extreme intakes, the percentage of participants with a cholesterol consumption< 300 mg/day increased from 40.8% in 1999 to 43.6% in 2009 for men (multivariate-adjusted p for trend = 0.04) and from 57.8% to 61.4% in women (multivariate-adjusted p for trend = 0.06). Calcium intake > 1 g/day decreased from 53.3% to 46.0% in men and from 47.6% to 40.7% in women (multivariate-adjusted p for trend< 0.001). Adequate iron intake decreased from 68.3%to 65.3% in men and from 13.3% to 8.4% in women (multivariate-adjusted p for trend< 0.001). Conversely, no significant changes were observed for carbohydrates, protein, total fat (including saturated, monounsaturated and polyunsaturated fatty acids), fibre, vitamins D and A. Conclusion: Fewimprovements were noted in adherence to dietary recommendations in the Geneva population between 1999 and 2009. The low and decreasing prevalence of adequate calcium and iron intake are of concern.

Temporal and spatial distribution of Leishmania mexicana infections in a population of Neotoma micropus

A 19-month mark-release-recapture study of Neotoma micropus with sequential screening for Leishmania mexicana was conducted in Bexar County, Texas, USA. The overall prevalence rate was 14.7% and the seasonal prevalence rates ranged from 3.8 to 26.7%. Nine incident cases were detected, giving an incidence rate of 15.5/100 rats/year. Follow-up of 101 individuals captured two or more times ranged from 14 to 462 days. Persistence of L. mexicana infections averaged 190 days and ranged from 104 to 379 days. Data on dispersal, density, dispersion, and weight are presented, and the role of N. micropus as a reservoir host for L. mexicana is discussed.

Oviposition activity and seasonal pattern of a population of Aedes (Stegomyia) aegypti (L.) (Diptera: Culicidae) in subtropical Argentina

Monthly oviposition activity and the seasonal density pattern of Aedes aegypti were studied using larvitraps and ovitraps during a research carried out by the Public Health Ministry of Salta Province, in Tartagal, Aguaray and Salvador Mazza cities, in subtropical Argentina. The A. aegypti population was active in both dry and wet seasons with a peak in March, accordant with the heaviest rainfall. From May to November, the immature population level remained low, but increased in December. Ae. aegypti oviposition activity increased during the fall and summer, when the relative humidity was 60% or higher. Eggs were found in large numbers of ovitraps during all seasons but few eggs were observed in each one during winter. The occurrence and the number of eggs laid were variable when both seasons and cities were compared. The reduction of the population during the winter months was related to the low in the relative humidity of the atmosphere. Significant differences were detected between oviposition occurrences in Tartagal and Aguaray and Salvador Mazza cities, but no differences in the number of eggs were observed. Two factors characterize the seasonal distribution pattern of Ae. aegypti in subtropical Argentina, the absence of a break during winter and an oviposition activity concomitant of the high relative humidity of the atmosphere.

Role of enhanced detoxication in a deltamethrin-resistant population of Triatoma infestans (Hemiptera, Reduviidae) from Argentina

Deltamethrin and other pyrethroids have been extensively used in Argentina since 1980, for the chemical control of Triatoma infestans Klug (Hemiptera: Reduviidae). Recently, resistance to deltamethrin was detected in field populations by the survival of bugs exposed by topical application to the diagnostic dose estimated on the CIPEIN susceptible strain. Results of the current study showed low resistant ratios (RRs) to deltamethrin for the resistant populations (RR ranged from 2.0 for San Luis colony to 7.9 for Salta colony). Biochemical studies were made on the most resistant colony (Salta) and the susceptible strain (CIPEIN), in order to establish the importance of degradative mechanisms as a cause of the detected resistance. Esterase activity was measured on 3 days old first instars through phenylthioacetate and a-naphtyl acetate activities. The results showed a significant difference in no cholinesterase esterase activity from susceptible (7.6 ± 0,7 µM S./i.min.) and Salta resistant colony (9.5 ± 0.8 µM S./i.min.). Cytochrome P450 mono-oxygenase (P450) activity was measured on individual insects through ethoxycoumarine deethylase (ECOD) activity using a fluorescence micro plate reader. The dependence of ECOD activity on age and body region of the nymphs, and pH and time of incubation were studied in order to optimize the measurement. As a result, comparative studies were performed on abdomens of 2 days old first instars at pH 7.2 and 4 h incubation time. ECOD activity of first nymphs was significantly lower in the susceptible colony (61.3 ± 9.08 pg ECOD/ insect) than in the resistant one (108.1± 5.7 pg ECOD/ insect). These results suggest that degradative esterases (no-cholinesterase) and mono-oxygenases cytochrome P450, play an important role in the resistance to deltamethrin in Salta colony from Argentina.

A Survey of Health Service Utilisation and Health Needs of a Population of Patient with HIV/ AIDS

This study described the demographic and medical characteristics of a population of patients with HIV/AIDS attending the department of Genito-Urinary Medicine (GUM) at a major Dublin hospital. The study population's utilisation of statutory and voluntary medical and social services at primary care level, satisfaction with services received and perceived need for services examined. The information obtained was used to make recommendations concerning the provision of care to patients with HIV/AIDS. The study was carried out between February and November 1994. Data was collected from a consecutive sample of eighty inpatients using n interviewer-administered questionnaire which contained both closed and open questions. The first forty patients interviewed were reviewed six months following the initial interview to document changes in physical condition and uptake of medical services over that time period. Data for the second part of the study was obtained by review of the patients' medical case notes and interview with the individual hospital medical social worker assigned to each patient. Over ninety percent of respondents were from the Greater Dublin Area. Almost three quarters were intravenous drug users (IVDUs), and the majority of these patients came from south inner city Dublin. The methodology was biased towards sampling patients with advanced disease and 73% had CDC Stage 4 disease. Twenty percent required some assistance with the activities of daily living when first interviewed. Most were reliant on informal carers. Social and physical dependency increased substantially over the six month period of the follow-up study of forty patients. Financial difficulties were identified as a particular area of need. Only ten percent of those interviewed were in current employment and over 80% were dependent on statutory payments. There is a need for greater co-ordination between the providers of services to patients HIV/AIDS and an improved system of data collection regarding patients' uptake of services and unmet needs is required to assist in future service planning.This resource was contributed by The National Documentation Centre on Drug Use.

Evolution of life history traits in a natural population of the shrew Crocidura russula

Abstract Life history traits encompass all the decisions concerning fitness an individual is faced with during his life. The study of these traits is crucial to understand the factors shaping the biology of living organisms. Up until now, most of the information on the evolution of life history traits comes from laboratory studies. While these studies are interesting to test the effect of specific parameters, their conclusions are difficult to extrapolate to natural populations. Investigating the evolution of life history traits in natural populations is of great interest. This may be tricky because it requires information on reproduction, survival and morphology of individuals. Mark-recapture methods allow most of this information to be obtained. However, when direct observations of a species are not possible due to its ecology, indirect methods must be used to infer lifetime reproductive success. In this case, molecular markers are particularly helpful in assessing the genetic relationships between individuals and allow the construction of a pedigree. This thesis focuses on a natural population of a small insectivorous mammal, the greater white-toothed shrew, Crocidura russula. Because of its hidden lifestyle, the two complementary techniques mentioned above were combined to gather information on this population. The data were used to explore diverse aspects of evolutionary biology. We demonstrated that the high genetic variance displayed by the species was not maintained by its mating system because this shrew was less monogamous than previously thought. The large genetic diversity was most likely promoted by gene flow from the neighborhood. Dispersal was thus a central topic in this thesis. We showed that dispersal was not driven by inbreeding avoidance. In addition, we did not find any inbreeding depression in the population. Dispersal was promoted by a high number of vacant territories in the population for both sexes, meaning that territory acquisition played an important role in driving dispersal. Moreover, dispersal propensity was shown to have a genetic basis and, once achieved, to have no effect on individual fitness. Body mass was found to be a life history trait strongly influenced by sexual and viability selection in both sexes. Larger individuals had higher access to reproduction through territory acquisition and defense than lighter ones. By contrast, intermediate size individuals were favored by viability selection presumably because of ecological constraints and metabolic costs. Finally, we demonstrated that the majority of the life history traits in our shrew population has the potential to evolve because they maintained substantial amounts of additive genetic variance. Nonetheless, life history traits had no significant heritability due to their high level of nonadditive or environmental variance. Résumé Les traits d'histoire de vie comprennent toutes les décisions auxquelles un individu est confronté au cours de sa vie et qui concernent sa valeur adaptative. L'étude de ces traits est cruciale pour comprendre les facteurs qui façonnent la biologie des êtres vivants. Jusqu'à ce jour, la majorité des informations sur l'évolution des traits d'histoire de vie provient d'études réalisées en laboratoire. Alors que ces études sont intéressantes pour tester l'effet de paramètres spécifiques, leurs conclusions sont difficilement extrapolables aux populations naturelles. Il est particulièrement intéressant d'étudier l'évolution des traits d'histoire de vie dans des populations naturelles. Toutefois, ces études peuvent se révéler difficiles parce qu'elles requièrent des informations sur la reproduction, la survie et la morphologie des individus. Des méthodes de marquage-recapture permettent d'obtenir ces informations. Cependant, lorsque l'écologie de l'espèce rend les obervations directes impossibles, des méthodes indirectes doivent être utilisées pour obtenir le succès reproducteur des individus. Dans ce cas, les marqueurs moléculaires sont particulièrement utiles pour évaluer les relations génétiques entre individus et permettre la construction d'un pedigree. Cette thèse porte sur une population naturelle d'un petit mammifère insectivore, la musaraigne musette, Crocidura russula. Parce que cette espèce présente un mode de vie souterrain, les deux techniques complémentaires mentionnées ci-dessus ont été combinées pour acquérir les informations nécessaires. Les données ont été utilisées pour explorer divers aspects de biologie evolutive. Nous avons montré que la grande quantité de variance génétique trouvée chez cette espèce n'est pas maintenue par son système d'appariement. Celle-ci s'est en effet avérée être moins monogame que ce qui était admis jusqu'ici. Sa grande diversité génétique est plutôt entretenue par le flux de gènes provenant du voisinage. La dispersion a donc été un sujet phare dans cette thèse. Nous avons montré qu'elle n'est pas provoquée par un évitement de la consanguinité et nous n'avons pas trouvé de dépression de consanguité dans notre population. L'acquisition d'un territoire joue par contre un rôle important dans la dispersion. En outre, la dispersion possède une base génétique chez cette espèce. De plus, une fois qu'ils ont dispersé, les individus n'ont pas une valeur adaptative differente d'individus philopatriques. Le poids s'est avéré être un trait d'histoire de vie fortement influencé par la sélection sexuelle et de viabilité chez les deux sexes. Les gros individus ont accès à la reproduction parce qu'ils acquièrent et défendent un territoire plus facilement que les plus légers. Au contraire, les individus de taille intermédiaire sont favorisés par la sélection de viabilité, certainement à cause de contraintes écologiques et de coûts métaboliques. Finalement, nous avons montré que la majorité des traits d'histoire de vie dans notre population a le potentiel d'évoluer parce qu'elle maintient des quantités considérables de variance génétique additive. Néanmoins, l'héritabilité de ces traits d'histoire de vie n'est pas significative à cause de la grande quantité de variance non-additive ou environmentale associée à ces traits.

The role of triple infection with hepatitis B virus, hepatitis C virus, and human immunodeficiency virus (HIV) type-1 on CD4+ lymphocyte levels in the highly HIV infected population of North-Central Nigeria

We set out to determine the seroprevalence of hepatitis B and C among human immunodeficiency virus type-1 (HIV-1) infected individuals in North-Central Nigeria to define the influence of these infections on CD4+ lymphocytes cells among our patients as access to antiretroviral therapy improves across the Nigerian nation. The CD4+ values of 180 confirmed HIV-1 infected individuals were enumerated using a superior fluorescence-activated cell sorter system. These patients were tested for the presence of hepatitis B surface antigen and anti-hepatitis C virus (HCV) using third generation enzyme-linked immunosorbent assays. Fifty (27.8%) patients had active hepatitis B virus (HBV) infection while 33 (18.3%) tested positive for anti-HCV antibody. Of these infections, 110 (61.1%), 37 (20.6%), and 20 (11.1%) had HIV only, HBV/HIV-only, and HCV/HIV-only respectively. A HBV/HCV/HIV coinfection prevalence of 7.2% (13 patients) was recorded. Patients coinfected with HIV/HBV/HCV appeared to have lower CD4+ counts (mean = 107 cells/µl; AIDS defining) when compared to HBV/HIV-only (mean = 377 cells/µl), HCV/HIV-only (mean = 373 cells/µl) and patients with mono HIV infection (mean = 478 cells/µl). Coinfection with HBV or HCV is relatively common among HIV-infected patients in Nigeria and should be a big consideration in the initiation and choice of therapy.

Aerobic and functional capacities in a selected active population of European octogenarians

Master athletes are often considered to represent the ideal rate of decline of aerobic function; however, most of the studies interested in active elderly people are often limited to people younger than 75. We aimed to determine the physiological adaptations and aerobic fitness in a selected European population of active octogenarians during maximal and submaximal exercise tests. Aerobic capacity was measured during maximal incremental tests on treadmill (TR) and cycle-ergometer (CE) and functional capacity during a 6-minute walk test (6-MWT) in 17 subjects aged 81.2 +/- 0.8 years. Pulmonary gas exchange and heart rate (HR) were continuously measured during the different exercise tests. Maximal oxygen consumption (V.O (2max)) on TR and CE was significantly higher than predicted values (TR: 28.7 +/- 1.2 vs. 17 +/- 0.5 ml . kg (-1) . min (-1); CE: 23 +/- 1.2 vs. 16 +/- 0.6 ml . kg (-1) . min (-1) for measured and predicted values respectively). V.O (2max) and HR (max), as well as V.O (2) and HR at the ventilatory threshold (V.O (2)T (V.E) and HR T (V.E)) were significantly higher on TR than on CE (HR (max): 144 +/- 4 vs. 138 +/- 4 bpm; V.O (2)T (V.E): 22.5 +/- 0.8 vs. 17.7 +/- 0.9 ml . kg (-1) . min (-1) for TR and CE respectively). V.O (2)T (V.E) and HR T (V.E) on TR were equivalent to V.O (2) and HR measured during the 6-MWT. HR T (V.E) on TR and mean HR during the 6-MWT were strongly correlated (R = 0.82, p < 0.01). Maintenance of regular physical activity provides high aerobic fitness, in octogenarians, as was shown by the higher values of our subjects in comparison to predicted values. Moreover, the close relation between the intensity developed at T (V.E) on TR and 6-MWT could support the idea that a walk test is a submaximal test performed at high intensity that could provide a basis for exercise prescription in an individualized manner in active elderly people.

Nutritional status using the Mini Nutritional Assessment questionnaire and its relationship with bone quality in a population of institutionalized elderly women.

Malnutrition, a risk factor for osteoporotic fractures, is frequent in elderly people and, is underdiagnosed and undertreated. There are only few studies on the nutritional status of elderly people in Europe. The Mini Nutritional Assessment (MNA) is a non invasive and validated questionnaire to evaluate nutritional status in elderly people, classified in three groups: 1 degree score < 17: malnourished, 2 degrees score >17 and < 24: at risk of malnutrition, 3 degrees score >24: well-nourished, with a maximum of 30 points. Quantitative ultrasound of bone (QUS) is a method for assessing quality of bone which can be easily performed in nursing homes. Therefore, these two tests allowed to study the relationships between nutritional status and ultrasonic parameters of bone in 78 institutionalized women aged 86 +/- 6 years, living in 11 nursing homes around Lausanne (Switzerland). All were assessed by the MNA, had a measurement of the tricipital skin fold and of the grip strength. Functional status was evaluated by the scale "Activity of Daily Living" (ADL), and serum albumin level was measured when permitted. All had QUS of the calcaneus (with an Achilles, GE Lunar). The measured parameters are the Broadband Ultrasound Attenuation (BUA), attenuation of a band of ultrasonic frequencies through the medium, expressed in dB/MHz, and the Speed of Sound (SOS), speed of the ultrasounds through the medium, expressed in m/s. A third parameter, the stiffness index (SI), expressed as a percentage of the values obtained by the manufacturer in a young population and derived from BUA and SOS, was calculated automatically : SI = (0.67xBUA) + (0.28xSOS) - 420, expressed in percent compared to a young adult population (%YA). Fifteen percent of the women were undernourished and 58% were at risk of malnutrition. As expected, compared with the well-nourished minority, undernourished subjects had significant lower body mass index (BMI), tricipital skin fold (TSF), ADL score and albumin level (p < 0,01). The subjects "at risk of malnutrition" had significant lower BMI, ADL score (p < 0.01), tricipital skin fold and serum albumin (p < 0.05). Ultrasound parameters were low independently of the nutritional status. MNA score correlated significantly with tricipital skin fold (r = 0.508, p < 0.01), ADL (r = 0.538, p < 0.01) and albumin serum level (r = 0.409, p = 0.01). There was a trend for a correlation between the MNA and the ultrasound parameter BUA (r = 0.207, p = 0.07), whereas no correlation was found with SOS and SI. A multivariate analysis showed that tricipital skin fold and ADL explained 61% of the variance of the MNA. In conclusion, using simple and non invasive methods, this study showed that malnutrition and osteoporosis are frequent in institutionalized elderly persons in our country, and the ultrasound parameters are influenced by many others factors in addition to nutrition, especially at this age and in elderly residents of nursing homes.

Latitude gradients in melanoma incidence and mortality in the non-Maori population of New Zealand

The variation with latitude of incidence and mortality for cutaneous malignant melanoma (CMM) in the non-Maori population of New Zealand was assessed. For those aged 20 to 74 years, the effects of age, time period, birth-cohort, gender, and region (latitude), and some interactions between them were evaluated by log-linear regression methods. Increasing age-standardized incidence and mortality rates with increasing proximity to the equator were found for men and women. These latitude gradients were greater for males than females. The relative risk of melanoma in the most southern part of New Zealand (latitude 44 degrees S) compared with the most northern region (latitude 36 degrees S) was 0.63 (95 percent confidence interval [CI] = 0.60-0.67) for incidence and 0.76 (CI = 0.68-0.86) for mortality, both genders combined. The mean percentage change in CMM rates per degree of latitude for males was greater than those reported in other published studies. Differences between men and women in melanoma risk with latitude suggest that regional sun-behavior patterns or other risk factors may contribute to the latitude gradient observed.

HLA-Bw4 identifies a population of HIV-infected patients with an increased capacity to control viral replication after structured treatment interruption.

OBJECTIVES: After structured treatment interruption (STI) of treatment for HIV-1, a fraction of patients maintain suppressed viral loads. Prospective identification of such patients might improve HIV-1 treatment, if selected patients are offered STI. METHODS: We analysed the effect of previously identified genetic modulators of HIV-1 disease progression on patients' ability to suppress viral replication after STI. Polymorphisms in the genes killer cell immunoglobulin-like receptor 3DLI (KIR3DL1)/KIR3DS1, human leucocyte antigen B (HLA-B) and HLA Complex P5 (HCP5), and a polymorphism affecting HLA-C surface expression were analysed in 130 Swiss HIV Cohort Study patients undergoing STI. Genotypes were correlated with viral load levels after STI. RESULTS: We observed a statistically significant reduction in viral load after STI in carriers of HLA-B alleles containing either the Bw480Thr or the Bw480Ile epitope (mean adjusted effect on post-STI viral load: -0.82 log HIV-1 RNA copies/ml, P < 0.001; and -1.12 log copies/ml, P < 0.001, respectively). No significant effects were detected for the other polymorphisms analysed. The likelihood of being able to control HIV-1 replication using a prespecified cut-off (viral load increase < 1000 copies/ml) increased from 39% in Bw4-negative patients to 53% in patients carrying Bw4-80Thr, and to 65% in patients carrying Bw4-80Ile (P = 0.02). CONCLUSIONS: These data establish a significant impact of HLA-Bw4 on the control of viral replication after STI.

How to increase the population of a Phlebotomus perniciosus (Diptera: Psychodidae) colony: a new method

The sandfly Phlebotomus perniciosus is the most widespread vector of Leishmania infantum in Spain. Laboratory colonisation represents the most feasible source of information on the biology of these insects, but in conducting any study, the density of individuals in the colony may drop to such an extent that it is sometimes difficult to recover the initial population levels. A new technique was tested for the recovery of sandfly eggs in three different colonies; the recovery rate was studied by comparing the standard method of mass rearing with this new method of colony management. The results demonstrate a mean increase of 18.4% in adult production, a growth in colony productivity that justifies the inclusion of this process in the routine maintenance of any colony of sandflies.

Genetic variability in a population of arbuscular mycorrhizal fungi causes variation in plant growth.

Different species of arbuscular mycorrhizal fungi (AMF) alter plant growth and affect plant coexistence and diversity. Effects of within-AMF species or within-population variation on plant growth have received less attention. High genetic variation exists within AMF populations. However, it is unknown whether genetic variation contributes to differences in plant growth. In our study, a population of AMF was cultivated under identical conditions for several generations prior to the experiments thus avoiding environmental maternal effects. We show that genetically different Glomus intraradices isolates from one AMF population significantly alter plant growth in an axenic system and in greenhouse experiments. Isolates increased or reduced plant growth meaning that plants potentially receive benefits or are subject to costs by forming associations with different individuals in the AMF population. This shows that genetic variability in AMF populations could affect host-plant fitness and should be considered in future research to understand these important soil organisms.