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PubMed2002

The selection and evolution of viral quasispecies in HIV-1 infected children.

OBJECTIVES: To analyse the diversity and divergence of the viral populations in three mother-child pairs in longitudinally obtained samples for up to 7 years. METHODS: Peripheral blood mononuclear cells were obtained from three mothers at delivery and three to four samples were obtained from each of their children from 1.5 months up to 78 months of age. The V3 region of HIV-1 was amplified by polymerase chain reaction, cloned and sequenced. HIV-1 DNA sequence comparisons were performed by phylogenetic analysis. RESULTS: The viral population was initially homogenous in two children but highly heterogeneous in one child. Three patterns of vertical transmission seemed to have occurred: transmission of the most prevalent maternal strain, of a minor maternal strain and of multiple maternal strains. In one child, a possible reappearance of a maternal sequence was observed at 34 months of age. CONCLUSIONS: Children may become infected with the most prevalent maternal strain, a minor maternal variant or multiple maternal quasispecies. Maternal viral variants may reappear in children after several years of infection and could possibly be derived from a reservoir of founder quasispecies established during the children's primary HIV-1 infection.

Adult↗
PubMed1992

Eikenella corrodens in human oral and non-oral infections: a review.

There is substantial evidence in support of the existence of distinct clinical forms of human periodontal disease. Moreover, these different forms of periodontal disease may be associated with relatively distinct subgingival microflora, often involving microaerophilic or anaerobic Gram-negative bacterial species. Eikenella corrodens is a facultative Gram-negative bacillus which is a common inhabitant of the oral cavity and the intestinal and genital tracts. Its primary ecologic niche within the oral cavity appears to be dental plaque, both in periodontally healthy individuals and in periodontitis patients. However, E. corrodens is recognized as an infrequent human pathogen capable of causing extraoral infections, either as the sole infectious agent or as part of a mixed infection, its potential role in the etiology of periodontal disease is not well understood. E. corrodens is often present in the supra- and subgingival plaque of periodontally healthy subjects. On the basis of cross-sectional and longitudinal studies, E. corrodens appears to be somewhat more prevalent in subgingival plaque samples of periodontitis subjects than periodontally healthy individuals. However, the percentage of E. corrodens in the total cultivable microflora did not vary between the two groups. Microbiologic studies attempting to define the relationship between E. corrodens and periodontal disease assume that this species is essentially homogeneous and that all strains exhibit comparable pathogenic potential. However, E. corrodens exhibits 1) variable colony morphology, biochemical and serologic reactivity; 2) marked phenotypic diversity with respect to outer membrane protein and lipopolysaccharide structure; and 3) marked diversity in the restriction patterns of total genomic DNA. Thus, it is possible that a limited number of clones of E. corrodens may be associated with periodontal disease and/or extraoral infection, while other strains are relatively harmless commensals. Additional studies, possibly employing strain-specific nucleic acid probes, may be required to define the role of E. corrodens as a human periodontal pathogen.

Animals↗
PubMed1965

Pathways of cellular morphogenesis. A diversity in Nitella.

Evidence is presented to show that a given change in cell form or size may generally be brought about by a variety of patterns of local surface distortion and expansion. Structural and chemical features of the cell which are important in morphogenesis may thus be expected to relate not to form per se but to the kinetics of surface behavior which establish form. These kinetics evaluate both the rate at which local regions of cell surface expand and the directed character (anisotropy) of this expansion. These variables have been studied in model systems and, through marking experiments, in growing cells of various shapes in Phycomyces, Clypeaster, and particularly Nitella. In the latter plant, prominent "giant internodes" display a well defined longitudinal anisotropic expansion devoid of sizeable gradients in expansion rate. These cells have their origin, however, in apical cells which have a pronounced gradient in area expansion rate (maximal at the tip). The great part of the expansion in the apical cell is apparently isotropic (equal in all directions), but the basal region often shows predominant expansion laterally. This transverse stretching in the apical cell could align cell wall texture and possibly fibrous cytoplasmic constituents, such as microtubules, into configurations significant in later morphogenetic stages, including the elongation of the internodes.

Eukaryota↗
PubMed2005

Illuminating cases: understanding the economic burden of illness through case study household research.

Understanding the economic burden of illness for households can inform pro-poor health and social protection policy, yet research is in its infancy and appropriate methods require further debate. Quantitative studies are powerful when applied to the right health policy questions, including the measurement of illness cost burden indicators. However, this paper argues that not all dimensions of economic burden can be measured easily, some dimensions relevant to policy, such as social actors' responses to illness and their strategies to cope with illness costs, cannot be reduced to quantitative indicators at all, and large-scale surveys may overlook context-specific processes operating at household level that influence people's paths in and out of poverty as a result of illness. This leaves scope for longitudinal case-study household research to enhance understanding of economic burden and provide additional policy insights on how to better protect households from cost burdens and improve resilience. Drawing on the experience of research in urban Sri Lanka, the paper sets out several comparative advantages of case study research in this area. First, it complemented household survey data by revealing the complex and dynamic nature of illness costs and how these cost patterns (for example, sudden cost peaks) influenced household ability to manage costs. Secondly, it improved understanding of vulnerability or resilience to illness costs by capturing the diverse resources, within and outside the household, used by people to cope with illness costs, and the social institutions and decision-making processes that influenced access to them. Thirdly, the cases enabled the research to develop a picture of the inter-connected factors mediating the impact of illness on livelihood outcomes.

Adaptation, Psychological↗
PubMed2004

Stages of faith and identity: birth to teens.

In closing, some of the strengths, limitations, and criticisms of faith development theory need to be acknowledged. Fortunately, there was gender balance in the formative sample of 359 interviews from which the theory of faith development derived (50% each of male and female respondents). In the original sample, Protestants made up 45% of the interviewees, Catholics represented 36.5%, 11.2% were Jews, and 3.6% were Orthodox Christians. A remaining 3.6% were "other." Given the growth in the numbers of adherents to other major traditions in the United States, interview research needs to be conducted to widen the sample to include Muslim, Buddhist, and secular respondents. Interviewees have not been studied longitudinally. Furthermore, most of the foundational research was conducted in the 1 980s and early 1990s. A new major round of faith development interviews could shed light on the impacts on peoples' faith of "globalization" and the features of experience that have come to be called the "postmodern condition." These phenomena reflect patterns of radical secularization and the erosion of religious and moral authority on the one hand and, paradoxically, the worldwide growth of fundamentalist and conservative faith practices on the other. Add to these phenomena the interest of many "nonchurched" persons in "spirituality" and we begin to grasp the richness and diversity that faith development research encounters today. Professor Heinz Streib of the University of Bielefeld is conducting the most significant research in the faith development tradition. The research he and his colleagues are conducting in Europe and in the United States promises to yield some tangible data and insights into these issues. To date, faith development theory has not been incorporated into child, adolescent, and family psychiatric interviewing and case formulation to any appreciable or measurable degree. These perspectives and inroads into the interior lives and thought processes of young people, however, may be helpful in the understanding of normal and pathologic development and of healthy and psychiatrically ill children and adolescents. Further collaborative work in this area is needed among psychiatrists, clinical psychologists, psychologists of religion, religious educators, and theologians.

Adolescent↗
PubMed1990

Effect of season on physical activity score, back extensor muscle strength, and lumbar bone mineral density.

Seasonal variation in physical activity, back extensor muscle strength (BES), and bone mineral density (BMD) of the lumbar spine was studied in 65 healthy postmenopausal women. Physical activity score (PAS) was assessed with an ordinal scale (0-18); this score and the BES were obtained monthly for 2 years (25 readings). BMD values were obtained semiannually (5 readings). A periodic (cosine) regression model was fit to each subject's PAS and BES data to obtain individual estimates of the annual peak day d and the average annual range due to seasonality. There was a strong (P less than 0.001) seasonal pattern in physical activity; August 3 was the average peak day, and the seasonal range was 2.0 PAS units. There was modest (P = 0.047) seasonality in BES; June 6 was the estimated peak day, and the seasonal range was 8.22 pounds (about 7% of the 0.002), and the highest monthly average BMD was in August. This seasonal range of 1.4% is larger than the average annual decline with age in BMD observed in longitudinal studies of postmenopausal women. The results of this study have important implications for the planning of longitudinal studies involving changes in physical activity or bone mass in geographic areas with diverse seasons.

Aged↗
PubMed2005

The odds that clinically unrecognized poor or partial adherence confuses population pharmacokinetic/pharmacodynamic analyses.

Electronic compilation of ambulatory patients' or trial participants' dosing histories has revealed that a wide range of dosing patterns, markedly skewed toward underdosing, occur in virtually every disease and treatment situation so far studied. In planning ambulatory trials and their analyses, one should recognize that patients' variable exposure to test drugs, created by their diversely erratic execution of protocol-specified dosing regimens, is generally the single largest source of variance in drug responses. Trial subjects' erratic dosing behaviour may, if ignored, weaken the trial's assay sensitivity. In contrast, reliably compiled and soundly analyzed dosing histories may greatly inform the analysis of the trial. Dosing histories found to be associated with suboptimal clinical results can highlight particular dosing patterns that should be avoided. Thus begins the sequence leading from first observations, to repeat observations, to ethically possible experimental designs, to causal inference, i.e., learning and then confirming. With the broadening use of electronic monitoring to estimate longitudinal drug exposure, the need exists for an explicit discipline that concerns itself with "what the patient does with the drug". It is called Pharmionics.

Anti-HIV Agents↗
PubMed2005

Freshwater mussel shells as environmental chronicles: geochemical and taphonomic signatures of mercury-related extirpations in the North Fork Holston River, Virginia.

This study utilized freshwater mussel shells to assess mercury (Hg) contamination in the North Fork Holston River that extirpated (caused local extinctions of) a diverse mussel fauna. Shells (n = 366) were collected from five sites situated upstream (two sites), just below (one site), and downstream (two sites) of the town of Saltville, Virginia, where Hg was used to produce chlorine and caustic soda from 1950 to 1972. Shell samples were used to test the (1) utility of geochemical signatures of shells for assessing the spatial variation in Hg levels in the river relative to the contamination source and (2) value of taphonomy (post-mortem shell alteration) for distinguishing sites that differ in extirpation histories. Geochemical signatures of 40 shells, analyzed using atomic absorption spectroscopy, indicated a strong longitudinal pattern. All shells from the two upstream sites had low Hg concentrations (<5-31 microg/kg), shells directly below Saltville had variable, but dramatically higher concentrations (23-4637 microg/kg), and shells from the two downstream sites displayed intermediate Hg levels (<5-115 microg/kg) that declined with distance from Saltville. Two pre-industrial shells, collected at Saltville in 1917, yielded very low Hg estimates (5-6 microg/kg). Hg signatures were consistent among mussel species, suggesting that Hg concentrations were invariant to species type; most likely, highly variable Hg levels, both across sites and through time, overwhelmed any interspecific differences in Hg acquisition. Also, a notable postmortem incorporation of Hg in mussel shells seemed unlikely, as the Hg content was not correlated with shell taphonomy (r= 0.18; p = 0.28). The taphonomic analysis (n = 366) showed that the degree of shell alteration reliably distinguished sites with different extirpation histories. At Saltville, where live mussels have been absent for at least 30 years, shells were most heavily altered and fragmented. Conversely, fresh-looking shells abounded upstream, where reproducing mussel populations are still present. In summary, relic shells offered valuable spatio-temporal data on Hg concentrations in a polluted ecosystem, and shell taphonomic signatures discriminated sites with different extirpation histories. The shell-based strategies exemplified here do not require sampling live specimens and may augment more standard strategies applied to environmental monitoring. The approach should prove especially useful in areas with unknown extirpation and pollution histories.

Animals↗
PubMed1998

Models for the longitudinal genetic analysis of same-age twins: application to HDL cholesterol.

Models are presented for the analysis of longitudinal data from same-age twins which permit the exploration of a remarkably diverse array of alternative explanations for continuity and change during development. Data of this type permit the detection of new sources of genetic or environmental covariation during development that are not expressed at earlier ages and, because they include the effects of age-specific genes, the resulting heritability estimates are more reliable than those obtained from relatives who differ in age. The proposed models were applied to measurements of HDL cholesterol obtained on 81 pairs of monozygotic (MZ) twins and 69 dizygotic (DZ) pairs at 11, 12.5 and 14 years of age. All three MZ co-twin correlations were substantially higher than the self correlations across occasions, suggesting that new sources of genetic or environmental covariation must be expressed during early adolescence. This interpretation was confirmed by analysis of the full covariance matrices which showed that only models which assumed the expression of new or age-specific genes could explain the observed pattern of covariation. Because they include the effects of age-specific genes, the resulting heritabilities (0.80-0.83) were substantially higher than many previous estimates.

Adolescent↗
PubMed2003

Diverse range of fixed positional deformities and bone growth restraint provoked by flaccid paralysis in embryonic chicks.

Pancuronium bromide (PB) is used in neonates and pregnant women to induce limp, flaccid paralysis in order to allow mechanical ventilation during intensive care. Such non-depolarizing neuromuscular blocking drugs are administered to 0.1% of all human births in the UK. In this study, we examined PB effects on skeletal development in chick embryos. PB treatment produced skeletal deformities associated with significant reduction in longitudinal growth of all appendicular elements. This was associated with greater cartilage to bone ratios, indicating a preferential reduction in osteogenesis. PB also increased the incidence of knee joint flexion and tibiotarsal joint hyperextension. In addition to limb, spinal and craniofacial deformities, flaccid immobility appears to convert the normal geometric pattern of weight gain to a simple arithmetic accretion. This novel study highlights the potentially harmful effects of pharmacologically induced flaccid immobility on chick embryonic skeletal development. Whilst in ovo avian development clearly differs from human, our findings may have implications for the fetus, premature and term neonate receiving such non-depolarizing neuromuscular blocking drugs.

Abnormalities, Drug-Induced↗
PubMed2007

Apoplastic barriers to radial oxygen loss and solute penetration: a chemical and functional comparison of the exodermis of two wetland species, Phragmites australis and Glyceria maxima.

Few studies have examined exodermal development in relation to the formation of barriers to both radial oxygen loss (ROL) and solute penetration along growing roots. Here, we report on the structural development, chemical composition and functional properties of the exodermis in two diverse wetland grasses, Glyceria maxima and Phragmites australis. Anatomical features, development, the biochemical composition of exodermal suberin and the penetration of apoplastic tracers and oxygen were examined. Striking interspecific differences in exodermal structure, suberin composition and quantity per unit surface area, and developmental changes along the roots were recorded. Towards the root base, ROL and periodic acid (H(5)IO(6)) penetration were virtually stopped in P. australis; in G. maxima, a tight ROL barrier restricted but did not stop H(5)IO(6) penetration and the exodermis failed to stain with lipidic dyes. Cultivation in stagnant deep hypoxia conditions or oxygenated circulating solution affected the longitudinal pattern of ROL profiles in G. maxima but statistically significant changes in exodermal suberin composition or content were not detected. Interspecific differences in barrier performance were found to be related to hypodermal structure and probably to qualitative as well as quantitative variations in suberin composition and distribution within exodermal cell walls. Implications for root system function are discussed, and it is emphasized that sufficient spatial resolution to identify the effects of developmental changes along roots is crucial for realistic evaluation of exodermal barrier properties.

Cell Wall↗
PubMed2001

Four-year outcomes from adolescent alcohol and drug treatment.

OBJECTIVE: Knowledge of treatment response for alcohol and drug problems among adults is mounting; less is known about long-term outcome for adolescents who receive treatment for alcohol and drug problems. The current study examined youth substance involvement over 4 years (using five waves of data collection) following treatment for alcohol and drug abuse. METHOD: A cohort of youth (N = 162, 60% male) treated during adolescence (mean age = 16 years) was followed into young adulthood, a period associated with stabilization of alcohol use patterns and elevated risk for life problems secondary to both alcohol and drug use. Participants (14-18 years old) were consecutive admissions to inpatient adolescent alcohol and drug treatment centers in San Diego that were abstinence focused and based on the 12-step approach. RESULTS: Alcohol and other drug use were reduced during the 4 years posttreatment, with the exception of nicotine. The greatest prevalence reduction occurred for stimulants; modest changes were evident in alcohol and marijuana use. Nicotine was the most commonly used substance throughout the 4 years after treatment. Several distinct substance involvement trajectories were evident during the 4 years following treatment. CONCLUSIONS: Alcohol and drug use patterns during the 4 years following treatment highlight both changes and diversity in substance involvement as youth make the transitions from middle to late adolescence and into young adulthood. Findings demonstrate the importance of identifying transitional periods and the need for alternative intervention strategies that may help the progression of this population into young adulthood.

Adolescent↗
PubMedDate not supplied

Psychometric evaluation of the Differentiation of Self Inventory for adolescents.

BACKGROUND: Evidence of psychometric support is needed for use of the Differentiation of Self Inventory with adolescents as a clinical assessment instrument to evaluate psychotherapeutic progress and outcomes, and for its use as a research instrument to evaluate the effectiveness of interventions on the basis of Bowen family systems theory. OBJECTIVE: To examine the reliability and validity of the 46-item, self-report Differentiation of Self Inventory (DSI) for use with adolescents. METHOD: An ex post facto research design was used to determine the psychometric properties of the DSI for adolescents, and to test theoretically grounded hypotheses drawn from Bowen theory that linked differentiation of self with chronic anxiety and symptom development. The DSI, the State-Trait Anxiety Inventory, and the Symptom Pattern Scale were administered to an ethnically diverse sample of 363 adolescents 14 to 19 years of age. RESULTS: The DSI full scale demonstrated good internal consistency reliability, with a Cronbach's alpha coefficient of.84. Factor analysis yielded a six-factor structure, representing the multidimensionality of the DSI items among adolescents. As hypothesized, differentiation of self mediated the relation between chronic anxiety and symptom development (p <.001), indicating that greater differentiation of self predicted fewer symptoms over and above chronic anxiety, and lending support to the construct validity of the DSI in adolescent populations. CONCLUSIONS: The results of this study support the use of the DSI with adolescents. Future longitudinal studies are needed for definitive causal conclusions regarding the role that differentiation of self plays as a mediator between the relation of chronic anxiety and symptom development.

Adolescent↗
PubMed1984

Drug-induced rhythmic burst activity of cerebellar neurons.

The discharge of cerebellar neurons was investigated in the rabbit and the rat under the influence of pentobarbital, diazepam or medazepam. In the rabbit, these drugs are known to induce a rhythm ranging between 4 and 25 Hz in the red nucleus (RN) and the cerebellum (Cb). Purkinje cells (P cells) in the intermediate zone of the cerebellar cortex as well as neurons of the interposed nucleus (IPN) were found to discharge with burst patterns fully synchronized with the drug-induced RN rhythm. In contrast, P cells in the medial cerebellar zone responded to these drugs only with changes in their discharge rate. Since P cells of the intermediate longitudinal zone project to the RN mainly via the IPN, the present findings complement our previous results, indicating that the rhythmic electrical activity in the RN is initiated by the cerebellum. The three drugs had similar effects on the activity of cerebellar units in the rabbit and the rat. The investigation also shows that, in spite of the uniform morphological structure of the cerebellar cortex, P cells do not respond uniformly to a given drug: the diversity of findings published on the P cell response to barbiturates or benzodiazepine derivatives may be explained by differences in the recording sites.

Animals↗
PubMed2006

Predicting variation in the life course of adolescent mothers as they enter adulthood.

PURPOSE: The purpose of this article is to identify adolescent risk factors that can be used to predict life course pathways (normative, problem-prone, and psychologically vulnerable) in the transition from adolescence to young adulthood in a sample of adolescent mothers. In addition, a cumulative risk index is assessed for its ability to distinguish between the life-course pathways as a potential assessment tool for service providers. METHODS: This prospective longitudinal study is based on a diverse sample of adolescent mothers in the Northwest. Data have been collected from pregnancy through adulthood. Five risk factors were used (individually and in a cumulative risk index) to predict young mothers' life course pathways from age 17 through 23 years. RESULTS: A multinomial logistic regression indicated that, relative to the normative group, the problem-prone group had significantly greater odds of having a history of school problems, delinquency, and hard substance use. The psychologically vulnerable group had significantly greater odds of mental health problems, hard substance use, and marginally more delinquency. Importantly, the cumulative risk index (the sum of the five risk factors) predicted the patterns of transition into adulthood and demonstrated significant sensitivity and specificity in distinguishing those in the normative pathway from those in either the problem-prone or psychologically vulnerable pathway. CONCLUSIONS: Results suggest that specific risk factors assessed at pregnancy can differentiate among adolescent mothers who experience varying levels of success in their transition into early adulthood. The cumulative risk index demonstrates applied utility as a risk assessment tool capable of distinguishing among life-course pathways.

Adolescent↗
PubMed2000

RESEARCH: Warmwater Stream Bank Protection and Fish Habitat: A Comparative Study.

/ Fishes and their habitats were sampled in Harland Creek, Mississippi, for 3 years to compare the relative value of three types of bank treatment in an incised, warmwater stream. Semiannual samples were collected from 10 reaches: 3 reaches protected by each of the three types of protection (longitudinal stone toe, stone spurs, and dormant willow posts) and an unprotected, slowly eroding bend. Protection of concave banks of bends had no measurable effect on the habitat quality of downstream riffles. Although bends and adjacent downstream riffles were faunistically similar at the species level, catostomids and centrarchids were more dominant in pools and smaller cyprinids more dominant in riffles. Reaches with willow posts were slightly deeper than the others, most likely because of geomorphic factors rather than bank treatment. Mean water surface widths in reaches stabilized with stone spurs were 40% to 90% greater than for other treatments, and current velocities were greatest in reaches with stone toe. Patterns of fish abundance and species diversity did not differ significantly among treatments. However, principal components analysis indicated that the fish species distribution associated with the untreated reference site was distinct. Reaches stabilized with stone spurs supported significantly higher densities of large fish and higher levels of fish biomass per unit channel length than reaches with other bank treatments, generally confirming previous research in the region. Initial costs for spurs were comparable to those for stone toe and about three times greater than for willow posts.

Journal Article↗
PubMed2004

Patterns of gene expression reveal a temporally orchestrated wound healing response in the injured spinal cord.

Spinal cord injury (SCI) induces a progressive pathophysiology affecting cell survival and neurological integrity via complex and evolving molecular cascades whose interrelationships are not fully understood. The present experiments were designed to: (1) determine potential functional interactions within transcriptional expression profiles obtained after a clinically relevant SCI and (2) test the consistency of transcript expression after SCI in two genetically and immunologically diverse rat strains characterized by differences in T cell competence and associated inflammatory responses. By interrogating Affymetrix U34A rat genome GeneChip microarrays, we defined the transcriptional expression patterns in midcervical contusion lesion sites between 1 and 90 d postinjury of athymic nude (AN) and Sprague Dawley (SD) strains. Stringent statistical analyses detected significant changes in 3638 probe sets, with 80 genes differing between the AN and SD groups. Subsequent detailed functional categorization of these transcripts unveiled an overall tissue remodeling response that was common to both strains. The functionally organized gene profiles were temporally distinct and correlated with repair indices observed microscopically and by magnetic resonance microimaging. Our molecular and anatomical observations have identified a novel, longitudinal perspective of the post-SCI response, namely, that of a highly orchestrated tissue repair and remodeling repertoire with a prominent cutaneous wound healing signature that is conserved between two widely differing rat strains. These results have significant bearing on the continuing development of cellular and pharmacological therapeutics directed at tissue rescue and neuronal regeneration in the injured spinal cord.

Algorithms↗
PubMed2004

Longitudinal study of the excretion patterns of thermophilic Campylobacter spp. in young pet dogs in Denmark.

The Campylobacter excretion patterns of 26 domestic pet dogs were described in a longitudinal study. The dogs entered the study between 3 and 8 months of age and were monitored until 2 years of age. They were tested monthly for Campylobacter carriage in stool samples that were cultured on the Campylobacter-selective media CAT and modified CCDA agar at 37 and 42 degrees C. This study comprised 366 fecal swab samples, of which 278 (76.2%) were found to be Campylobacter positive, with the following distribution of species: 75.0% Campylobacter upsaliensis, 19.4% Campylobacter jejuni, 2.1% Campylobacter lari, 0.7% Campylobacter coli, and 2.8% Campylobacter spp. Isolates were typed by pulsed-field gel electrophoresis (PFGE) to elucidate the strain excretion pattern. All study dogs excreted Campylobacter spp. during the study period. At 3 months of age, 60% of the dogs carried Campylobacter, increasing to nearly 100% carriers at 1 year of age, whereafter the carriage rate decreased to 67% at 24 months of age. The PFGE types showed that individual dogs were often colonized by unique strains of C. upsaliensis for several months, up to 21 months or longer. These C. upsaliensis strains were either clonal (or underwent concurrent minor mutative changes) or independent strains. In contrast, the excreted C. jejuni isolates were much more diverse and, in most cases, only seen in one sample from each dog. A high degree of diversity among different dogs was seen. We conclude that young domestic pet dogs excreted Campylobacter spp. during the majority of their puppyhood and adolescent period. In general C. upsaliensis strains were excreted for months, with short-term interruptions by or cocolonization with other transitory Campylobacter spp., predominantly C. jejuni. C. jejuni was more prevalent in dogs between 3 months and 1 year of age than in dogs between 1 and 2 years of age.

Animals↗