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PubMed2005

Dietary patterns and colorectal adenomas in Japanese men: the Self-Defense Forces Health Study.

The role of dietary patterns in colorectal carcinogenesis remains unclear in Asian populations. Using 1999-2002 data, the authors investigated the association between dietary patterns and colorectal adenomas in 1,341 Japanese men who underwent total colonoscopy. Information about diet was obtained using a 74-item food frequency questionnaire prior to the colonoscopy. Three dietary patterns were generated by factor analysis: 1) a high-dairy, high-fruit and -vegetable, high-starch, low-alcohol pattern; 2) an "animal food" pattern; and 3) a Japanese pattern. Logistic regression analysis was used to estimate the odds ratio of having colorectal adenomas with the adjustment for potential confounding variables including body mass index, smoking, alcohol, and leisure-time physical activities. A significant inverse association was found for the high-dairy, high-fruit and -vegetable, high-starch, low-alcohol pattern; the odds ratios for the second, third, and fourth quartiles were 0.97 (95% confidence interval: 0.70, 1.36), 0.71 (95% confidence interval: 0.50, 1.01), and 0.62 (95% confidence interval: 0.43, 0.90), respectively, compared with the lowest (p(trend) = 0.003). Similar associations were observed for larger adenomas or for each subsite of the colorectum. The Japanese and "animal food" patterns were not clearly associated with colorectal adenomas. A dietary pattern including greater consumption of dairy products and fruits and vegetables with low alcohol consumption may be associated with decreased risk of colorectal adenomas.

Adenoma↗
PubMed2000

SPLASH: structural pattern localization analysis by sequential histograms.

MOTIVATION: The discovery of sparse amino acid patterns that match repeatedly in a set of protein sequences is an important problem in computational biology. Statistically significant patterns, that is patterns that occur more frequently than expected, may identify regions that have been preserved by evolution and which may therefore play a key functional or structural role. Sparseness can be important because a handful of non-contiguous residues may play a key role, while others, in between, may be changed without significant loss of function or structure. Similar arguments may be applied to conserved DNA patterns. Available sparse pattern discovery algorithms are either inefficient or impose limitations on the type of patterns that can be discovered. RESULTS: This paper introduces a deterministic pattern discovery algorithm, called Splash, which can find sparse amino or nucleic acid patterns matching identically or similarly in a set of protein or DNA sequences. Sparse patterns of any length, up to the size of the input sequence, can be discovered without significant loss in performances. Splash is extremely efficient and embarrassingly parallel by nature. Large databases, such as a complete genome or the non-redundant SWISS-PROT database can be processed in a few hours on a typical workstation. Alternatively, a protein family or superfamily, with low overall homology, can be analyzed to discover common functional or structural signatures. Some examples of biologically interesting motifs discovered by Splash are reported for the histone I and for the G-Protein Coupled Receptor families. Due to its efficiency, Splash can be used to systematically and exhaustively identify conserved regions in protein family sets. These can then be used to build accurate and sensitive PSSM or HMM models for sequence analysis. AVAILABILITY: Splash is available to non-commercial research centers upon request, conditional on the signing of a test field agreement. CONTACT: acal@us.ibm.com, Splash main page http://www.research.ibm.com/splash

Algorithms↗
PubMed1992

Sequential pattern formation in a model for skin morphogenesis.

During morphogenesis regular patterns often develop behind a frontier of pattern formation which travels across the prospective tissue. Here the authors consider the propagating patterns exhibited in a two-dimensional domain by a tissue interaction mechanochemical model for skin pattern formation. It is shown that the model can exhibit travelling waves of complex spatial pattern formation. Two alternative mechanisms that can produce such sequential patterning are presented. In particular, it is demonstrated that the specification of a simple quasi-one-dimensional pattern is all that is required to determine a complex two-dimensional pattern. Finally, the model solutions are related to actual pattern propagation during chick feather primordia initiation.

Animals↗
PubMed2004

Reproducibility and validity of major dietary patterns among Swedish women assessed with a food-frequency questionnaire.

Defining dietary patterns by factor analysis is an alternative approach to dietary assessment that has been used recently to examine diet-disease relations. However, only 1 study evaluated the reproducibility and validity of this method. Our aim was to assess both the validity and reproducibility of major dietary patterns based on data from a 60-item FFQ. We chose 2 independent random samples among over 60,000 women aged 40-74 y participating in the Swedish Mammography Cohort (SMC). In the validation study, the FFQ was compared with 4 7-d dietary records (DRs) among 129 women. For the reproducibility study, the FFQ was administered twice, 1 y apart in 212 women. By conducting factor analysis, 3 major dietary patterns were identified: healthy (high in vegetables, fruits, fish, poultry, tomato, cereal, and low-fat dairy products), Western (processed meat, meat, refined grains, sweets, and fried potatoes), and drinker (beer, wine and liquor, snacks) pattern. These 3 patterns explained 29-34% of the total variance in these 2 studies. The Spearman correlation coefficients between FFQ1 and FFQ2 (reproducibility) for healthy, Western, and drinker pattern were 0.63, 0.68, and 0.73, respectively (all P < 0.0001). Correlation coefficients between the FFQ and DRs (validity) for these patterns were 0.59, 0.50, and 0.85, respectively (all P < 0.0001). Our results indicate that identification of dietary patterns through factor analysis is a reproducible and valid method. The dietary patterns approach might be used in nutritional epidemiology as an alternative method of dietary assessment.

Adult↗
PubMed2005

Identification of a food pattern characterized by high-fiber and low-fat food choices associated with low prospective weight change in the EPIC-Potsdam cohort.

The aim of the study was to identify a dietary pattern predictive of subsequent annual weight change by using dietary composition information. Study subjects were 24,958 middle-aged men and women of the European Prospective Investigation into Cancer and Nutrition-Potsdam cohort. To derive dietary patterns, we used the reduced rank regression method with 3 response variables presumed to affect weight change: fat density, carbohydrate density, and fiber density. Annual weight change was computed by fitting a linear regression line to each person's body weight data (baseline, and 2- and 4-y follow-up) and determining the slope. In linear regression models, the pattern score was related to annual weight change. We identified a food pattern of high consumption of whole-grain bread, fruits, fruit juices, grain flakes/cereals, and raw vegetables, and of low consumption of processed meat, butter, high-fat cheese, margarine, and meat to be predictive of subsequent weight change. Mean annual weight gain gradually decreased with increasing pattern score (P for trend < 0.0001), i.e., subjects scoring high for the pattern maintained their weight or gained significantly less weight over time compared with subjects with an opposite pattern. However, the prediction of annual weight change by the food pattern was significant only in nonobese subjects. In this study population, we identified a food pattern characterized by high-fiber and low-fat food choices that can help to maintain body weight or at least prevent excess body weight gain.

Body Weight↗
PubMed2003

Patterns of CD4/CD8 T-cell ratio in dialysis effluents predict the long-term outcome of peritonitis in patients undergoing peritoneal dialysis.

BACKGROUND: The peritoneal immune compartment is a microenvironment with a particular T-cell repertoire and susceptible to local inflammation. To clarify the role of T lymphocytes in peritoneal immunity, the changes in T-cell subpopulations in peritoneal dialysis effluents (PDEs), and their influence on the response to the treatment of peritonitis and on its prognosis were studied in patients undergoing long-term, continuous ambulatory peritoneal dialysis (CAPD). METHODS: A cohort of 36 patients treated with CAPD and who had histories of peritonitis were divided into a group with rapid and a group with delayed response to antibiotics, and were followed for 3 years. CD4/CD8 T-cell ratios, T-cell cytokine mRNA expression patterns and transforming growth factor-beta1 (TGF-beta1) concentrations were examined in PDE during bouts of peritonitis. The change in 4 h D/P creatinine during the peritoneal equilibration test (PET) between year 0 and year 3 was expressed as deltaD/P creatinine. RESULTS: The serial changes in T-cell subsets in PDE during peritonitis showed two patterns: (i) pattern 1, manifest as a progressive increase in the CD4/CD8 ratio, and associated with a rapid response to treatment; and (ii) pattern 2, manifest as a progressive decrease in the CD4/CD8 ratio, and associated with a delayed response to treatment. The major T-cell phenotypes in PDE during peritonitis were Th1-CD4(+) and Tc2-CD8(+), determined by cloning techniques, RT-PCR and double immunofluorescence staining. TGF-beta1 in the effluent was undetectable in pattern 1 after 7-8 days, but remained detectable at 2 weeks in pattern 2. Pattern 2 patients had a significantly greater decrease (deltaD/P creatinine: -0.198+/-0.086) in solute transport than pattern 1 patients (deltaD/P creatinine: -0.036+/-0.077, P<0.05). CONCLUSIONS: These results suggest that a progressive decrease of the CD4/CD8 ratio in PDE correlates with a persistent expression of TGF-beta1, and plays a pathogenetic role in the evolution of peritonitis, PET deterioration and peritoneal fibrosis. Therefore, patterns of CD4/CD8 T-cell ratio in PDE may predict clinical outcomes of peritonitis in CAPD patients.

Adult↗
PubMed1996

Endometrial pattern in diethylstilboestrol-exposed women undergoing in-vitro fertilization may be the most significant predictor of pregnancy outcome.

The objective of this study was to compare prospectively pregnancy outcome as it is related to ultrasonic endometrial echo pattern in women exposed to diethylstilboestrol (DES) in utero by their mother's consumption with women not exposed to DES, all of whom were undergoing in-vitro fertilization (IVF). Pregnancy outcome relative to endometrial thickness and pattern was evaluated in 540 cycles of IVF including DES (n = 50) and non-DES-exposed (n = 490) women. Endometrial patterns were designated as p1 = solid; p2 = ring; and p3 = intermediate. DES patients exhibited p1 more often than the majority of the non-DES-exposed group. There was no significant difference in endometrial thickness among the cycles where p1 was noted when comparing the DES (10.3 mm) with the non-DES-exposed (10.7 mm) groups. Notably, within the group exhibiting p1, no pregnancies occurred in the 18 cycles of DES-exposed women compared with a 39.2% clinical pregnancy and 36.5% delivery rate in the non-DES-exposed controls (P < 0.0001 and P = 0.008 respectively). Pregnancy rates were not significantly different in the cycles where the other endometrial patterns were found when comparing the two groups. The impact of uterine shape on pregnancy outcome was also investigated. A T-shaped uterine configuration was noted in 11 out of 18 (61.1%) cycles of DES-exposed women with pattern p1 compared with nine out of 23 (39.1%) with pattern p2. Of cycles where a T-shaped uterus was demonstrated, none out of 11 (0%) with pattern p1 compared with four out of nine (44.4%) with pattern p2 resulted in pregnancy (P = 0.026). These data suggest that endometrial pattern is one of the most significant variables for pregnancy outcome in DES-exposed women undergoing IVF.

Adult↗
PubMed2001

Patterns of extraocular muscle weakness in vasculopathic pupil-sparing, incomplete third nerve palsy.

OBJECTIVE: To determine the pattern of extraocular muscle (EOM) paresis in incomplete vasculopathic third nerve palsies (3NP) that have normal pupillary function. METHODS: A retrospective study in a private practice and academic neuro-ophthalmic practice. Patients diagnosed with vasculopathic 3NP within 4 weeks of symptom onset were identified. The chart of each patient was reviewed to determine pupillary function and the pattern and degree of EOM and levator palpebrae paresis at the time of presentation. RESULTS: Of 55 patients with vasculopathic 3NP, 42 (76%) had normal pupillary function. Of these 42, 23 (55%) demonstrated an incomplete EOM palsy, defined as partially reduced ductions affecting all third nerve-innervated EOMs and levator (diffuse pattern) or partially reduced ductions that involved only some third nerve-innervated EOMs and levator (focal pattern). Twenty (87%) of these 23 patients showed a diffuse pattern of paresis; only three (13%) showed a focal pattern of paresis, one that affected only the superior rectus and levator muscles (superior division weakness). CONCLUSIONS: Based on our series, most patients with EOM/levator involvement in pupil-sparing, incomplete 3NP of vasculopathic origin have a diffuse pattern of paresis. In contrast, our review of the literature suggests that pupil-sparing 3NP of aneurysmal origin usually have a focal pattern of paresis. We propose that distinguishing these two patterns of EOM paresis may be helpful in differentiating between vasculopathic and aneurysmal 3NP. Future studies will be needed to confirm the clinical utility of this hypothesis.

Adult↗
PubMed2002

Dietary pattern analysis: a new direction in nutritional epidemiology.

Recently, dietary pattern analysis has emerged as an alternative and complementary approach to examining the relationship between diet and the risk of chronic diseases. Instead of looking at individual nutrients or foods, pattern analysis examines the effects of overall diet. Conceptually, dietary patterns represent a broader picture of food and nutrient consumption, and may thus be more predictive of disease risk than individual foods or nutrients. Several studies have suggested that dietary patterns derived from factor or cluster analysis predict disease risk or mortality. In addition, there is growing interest in using dietary quality indices to evaluate whether adherence to a certain dietary pattern (e.g. Mediterranean pattern) or current dietary guidelines lowers the risk of disease. In this review, we describe the rationale for studying dietary patterns, and discuss quantitative methods for analysing dietary patterns and their reproducibility and validity, and the available evidence regarding the relationship between major dietary patterns and the risk of cardiovascular disease.

Cluster Analysis↗
PubMed2004

Pattern of proliferative index (Ki-67) after anti-androgen manipulation reflects the ability of irradiation to control prostate cancer.

Anti-androgen (AA) therapy will cause hormone-sensitive prostate cancer cells to undergo apoptosis and/or enter the resting phase of the cell cycle. Although the decrease of tumor burden would be an advantage for tumor control when irradiation is subsequently added, the cells in resting phase would seemingly be less vulnerable to the usual type of radiation-induced cell killing via DNA strand breakage. In this study of patients with prostate cancer, we examined the proliferative index via Ki-67 staining of biopsy material before, during, and after withdrawal of leuprolide. We studied 15 previously untreated patients with locally advanced prostate cancer. Prostate biopsies were taken at three times: 1) initial diagnosis; 2) after 3 consecutive months of intramuscular 7.5 mg depot; and c) 6 weeks after the last dose. External beam radiation (EBRT) then delivered 66 Gy in 33 sessions to local fields. We used the ASTRO definition of prostate-specific antigen (PSA) failure. We measured serum luteinizing hormone and total testosterone coinciding with each biopsy date. Immunohistochemical staining was performed using Ki-67 antibody clone MIB-1. The follow-up ranged from 36 to 73 months (median 52 months). We discerned two perturbation patterns of Ki-67 with hormonal manipulation. Pattern 1 demonstrated a drop of Ki-67 labeling after leuprolide was in effect and then after leuprolide withdrawal, the Ki-67 rebounded to less than 120% of baseline. Pattern 2 also showed an initial drop with leuprolide but rebounded to more than 120%. Among eight patients demonstrating pattern 1, only one patient had a PSA failure. In contrast among patients with pattern 2, six of seven failed biochemically (Fisher's exact, p = 0.018). All patients had a LH less than 1.0 during leuprolide effect that rose with its withdrawal. There was no correlation of PSA failure with whether total testosterone did or did not rise to more than 100 ng/dl by the time of the withdrawal phase biopsy. Neither the percent of PSA decline during leuprolide nor the minor PSA rebound 6 to 8 weeks after leuprolide withdrawal correlated with the Ki-67 pattern. The pattern of perturbation of immunohistochemical staining for Ki-67 predicts biochemical failure after moderate-dose EBRT in patients with prostate cancer. Several recent analyses of combined EBRT and AA suggest that some patients may benefit from more prolonged use of AA. Because AA can have substantial side effects and is expensive, a method to select patients likely to benefit from long-term AA would be useful. After neoadjuvant AA manipulation, the Ki-67 perturbation pattern, but not the early PSA changes, may help select patients for long-term AA. The Ki-67 pattern might also be used to select patients needing escalated radiation dosage. Further validation of these concepts beyond this pilot study is suggested.

Aged↗
PubMed2006

Predicting outcomes on head-up tilt based on orthostatic hypotension patterns.

OBJECTIVE: To assess the frequency of different orthostatic hypotension (OH) patterns in patients having supine hypertension with OH ('SHOH') versus patients with OH and normal supine blood pressure ('OH alone'); and to relate OH patterns with outcomes on head-up tilt. METHODS: Consecutive patients with nonspecific dizziness were studied with a 10-min supine, 30-min head-up tilt test. Supine hypertension was diagnosed when supine systolic blood pressure (SBP) was at least 140 mmHg and/or supine diastolic blood pressure was at least 90 mmHg. OH was defined as SBP reduction of at least 20 mmHg within 3 min of tilt. OH patterns were identified corresponding to SBP time-curves during the initial 5 min of tilt: progressive, sustained and transient patterns. RESULTS: Among 400 patients tested, 31 had 'SHOH' and 39 had 'OH alone'. Frequencies of OH patterns were similar in both groups. The progressive OH pattern predicted symptomatic hypotension, leading to early tilt termination in all 'SHOH' and 88% of 'OH alone' patients. In comparison, tilt was early terminated in 33-48% of patients with sustained OH, transient OH and without OH. Early tilt termination was unrelated to age, gender, magnitude of supine SBP, pulse pressure and nadir SBP within 5 min tilt. CONCLUSIONS: Five minutes of postural challenge permitted assessing OH patterns. Outcome on protracted tilt was related to OH patterns, the worse outcome being likened to progressive OH, both in patients with 'SHOH' and in patients with 'OH alone'. Future studies will show whether OH patterns may serve as guidance for blood pressure therapy in selected patients.

Adult↗
PubMed2006

Pattern electroretinogram in glaucoma.

PURPOSE OF REVIEW: Several studies have shown that the pattern electroretinogram, a direct, objective method of measuring retinal ganglion cell function, is altered early in ocular hypertension and glaucoma. Renewed interest in the pattern electroretinogram for early detection of pre-perimetric glaucoma has been sparked by noninvasive and reproducible methods of recording using skin electrodes. RECENT FINDINGS: With the noninvasive pattern electroretinogram, response abnormalities have been detected in up to 50% of glaucoma suspects with normal standard perimetry. In early glaucoma (with either normal or high intraocular pressure), a reduction of intraocular pressure has sometimes yielded improvement in pattern electroretinogram amplitude. A prolonged steady-state stimulus presentation reduces the pattern electroretinogram amplitude and increases optic nerve blood flow in normal subjects, suggesting that sustained activity of retinal ganglion cells is physiologically associated with autoregulatory changes of the neural-vascular system. It is unknown whether this autoregulation is altered in glaucoma. The multifocal pattern electroretinogram does not seem to have an advantage over the pattern electroretinogram in the early detection of glaucoma. The photopic negative response of the diffuse flash electroretinogram has shown changes in glaucoma, but may not be able to detect retinal dysfunction in normal tension glaucoma. SUMMARY: The pattern electroretinogram is a noninvasive, direct, objective method that may be useful to clinicians in detecting early retinal ganglion cell dysfunction in glaucoma suspects. The pattern electroretinogram may also optimize treatment strategies based on improvement of retinal ganglion cell function.

Electroretinography↗
PubMed2004

Skin waste, vertex angle, and scar length in excisional biopsies: comparing five excision patterns--fusiform ellipse, fusiform circle, rhomboid, mosque, and S-shaped.

The common excision skin pattern is either a fusiform ellipse or another pattern with dissimilar length and width. The purpose of this study was to define the most advantageous skin pattern regarding skin waste, vertex angle, and scar length. Five skin excision patterns used traditionally for closure of round lesions were analyzed: fusiform ellipse, fusiform circle, rhomboid, mosque, and S-shaped. In the analysis, the pattern characteristics were formulated by geometric principles, from which the results were compared. The smallest skin waste was found in rhomboid and mosque patterns, whereas the largest skin waste was found in the fusiform circle and ellipse. The vertex angle was found to decrease monotonously with the excision length-to-width ratio for all patterns except the mosque shape, which is zero per definition. The paradigm stating that a vertex angle of 30 degrees or less is maintained for length-to-width ratios below 4 in the surgical ellipse was found incorrect. It holds only for rhomboid and S-shaped excisions. The scar length was found almost independent of the pattern, with a variance of 3 percent. The authors conclude that the most advantageous surgical skin patterns are the rhomboid and mosque excisions.

Biopsy↗
PubMed1987

Establishment and refinement of segmental pattern in the Drosophila embryo: spatial control of engrailed expression by pair-rule genes.

We are examining the development of the segmental body pattern of Drosophila by immunolocalization of engrailed, a developmental regulatory protein that maintains segmental subdivisions in the embryo, and is expressed in a spatially restricted (striped) manner that persists while the body pattern is being established and refined. A regulatory network among pair-rule segmentation genes establishes the striped pattern of engrailed expression. In general, mutations in particular pair-rule genes affect either even- or odd-numbered engrailed stripes. For example, fushi tarazu or odd-paired mutations delete even-numbered stripes, whereas paired mutations delete odd-numbered stripes. An analysis of engrailed expression in other mutants, including even-skipped odd-skipped double mutants, indicates that some pair-rule genes play a rule in establishing the correct width and position of engrailed stripes. Overall, the changes in engrailed pattern have consequences for final embryonic body pattern. Thus, the pair-rule loci, acting through engrailed, establish an early, general outline of body pattern. However, in several pair-rule mutants, engrailed patterns are dynamic, suggesting that as later events build upon this general rule to form the final body pattern, adjustments are made in response to the earlier pair-rule defect--that is, the pattern regulates.

Animals↗
PubMed1989

Neuronal development in the Drosophila compound eye: rap gene function is required in photoreceptor cell R8 for ommatidial pattern formation.

In the compound eye of Drosophila, cell-cell interactions are thought to play an important role in the determination of neuronal cell fate and pattern morphogenesis. Recent work on the bride of sevenless (boss) gene has demonstrated an inductive role for photoreceptor R8 in the differentiation of photoreceptor R7. These studies have shown that while R8 differentiates early in the scheme of ommatidial assembly, it continues to play an active role in subsequent patterning events. We describe studies on a new genetic locus rap (retina aberrant in pattern), whose functions are critical for normal pattern formation in the developing eye. Mutations in the rap gene perturb the early stages of pattern formation and lead to a variable number of photoreceptor cells (R cells) in each ommatidium. Experiments with a temperature-sensitive allele have shown that rap gene function is required during the period of development when pattern formation occurs. In addition, a somatic mosaic analysis of rap has shown that its function is required only in photoreceptor cell R8 for normal ommatidial patterning. These studies suggest an important role for rap in the initial events leading to pattern formation and are consistent with R8 playing a central role in directing ommatidial pattern formation.

Animals↗
PubMed2003

Patterns in randomly evolving networks: idiotypic networks.

We present a model for the evolution of networks of occupied sites on undirected regular graphs. At every iteration step in a parallel update, I randomly chosen empty sites are occupied and occupied sites having occupied neighbor degree outside of a given interval (t(l),t(u)) are set empty. Depending on the influx I and the values of both lower threshold and upper threshold of the occupied neighbor degree, different kinds of behavior can be observed. In certain regimes stable long-living patterns appear. We distinguish two types of patterns: static patterns arising on graphs with low connectivity and dynamic patterns found on high connectivity graphs. Increasing I patterns become unstable and transitions between almost stable patterns, interrupted by disordered phases, occur. For still larger I the lifetime of occupied sites becomes very small and network structures are dominated by randomness. We develop methods to analyze the nature and dynamics of these network patterns, give a statistical description of defects and fluctuations around them, and elucidate the transitions between different patterns. Results and methods presented can be applied to a variety of problems in different fields and a broad class of graphs. Aiming chiefly at the modeling of functional networks of interacting antibodies and B cells of the immune system (idiotypic networks), we focus on a class of graphs constructed by bit chains. The biological relevance of the patterns and possible operational modes of idiotypic networks are discussed.

Journal Article↗
PubMed2005

Genetic and environmental influences on skin pattern deterioration.

Sun exposure has been known to cause histological changes in the dermal layer of the skin. Using deterioration in the fine reticular patterning of the epidermal stratum corneum (skin pattern, as measured on the Beagley-Gibson scale) as a proxy measure of histological changes in the dermal layer, previous studies have typically assumed that degradation of skin pattern is largely caused by sun exposure. A twin study comprising 332 monozygotic twin pairs and 488 dizygotic twin pairs at ages 12, 14, and 16 was used to investigate the etiology of variation in skin pattern, particularly in relation to measured sun exposure and skin color. Our results indicate that although self-reported sun exposure is a significant contributor to variation in skin pattern, its effect is small, explaining only 3.4% of variation in skin pattern at age 14. Additive genetic effects explain 86% of variation in skin pattern at age 12 but these effects reduce with age so that 75% of variation is due to additive genetic effects at age 14 and 72% at age 16. This trend of diminishing genetic influences continues into adulthood, with 62% of variation due to non-additive genetic factors in a smaller adult sample (aged 32-86). Skin color explains 10.4% of variation in skin pattern at age 12, which is due to additive genetic influences common to both. Melanin content appears to provide a protective effect against skin pattern deterioration, perhaps because of the structural differences in melanosomes between different skin types or the free radical scavenging properties of melanin.

Adolescent↗
PubMed2003

Possible relationship of PFGE patterns of Moraxella catarrhalis between hospital- and community-acquired respiratory infections in a community hospital.

We describe a prospective study of molecular analysis of Moraxella catarrhalis isolated from a community hospital. Our study was designed to investigate the possible relationship of pulsed-field gel electrophoresis (PFGE) patterns of M. catarrhalis between hospital- and community-acquired respiratory infections. A nosocomial outbreak of M. catarrhalis was observed between September 2000 and September 2001. During the study period, 40 strains of M. catarrhalis were isolated from a total of 32 patients with respiratory infections (26 strains from 18 inpatients, and 14 strains from 14 outpatients). We compared the PFGE patterns in 40 strains of M. catarrhalis isolated from the respiratory tract of the study patients. The genomic types of M. catarrhalis were classified into three PFGE patterns (A, B, and C). Interestingly, the nosocomial outbreak of M. catarrhalis included two patterns (A and B). Of the three patterns, two patterns (A and B) were found in both inpatients and outpatients. More interestingly, two subtypes of pattern B (B1 and B4) were simultaneously found in both inpatients and outpatients. Our results indicated that PFGE with SmaI chromosomal digestion is a suitable technique to establish the inter-strain genetic relatedness of M. catarrhalis, and suggested that the outbreak of M. catarrhalis occasionally included miscellaneous PFGE patterns. The results also showed that PFGE patterns of M. catarrhalis isolates were similar between hospital- and community-acquired respiratory infections. Analysis of the subtypes suggested that there might be some association between hospital- and community-acquired respiratory infections caused by M. catarrhalis.

Aged↗