Non-syndromic and Syndromic Severe Acne in Adolescent Patients

Acne is a common skin disorder in adolescents. However, severe acne that is persistent and refractory to conventional treatment or has other associated symptoms should raise suspicion for non-syndromic or syndromic acne.

Systematic Review and Critical Appraisal of Urticaria Clinical Practice Guidelines: A Global Guidelines in Dermatology Mapping Project (GUIDEMAP)

BACKGROUND

Management of urticaria can be optimized with clinical practice guidelines (CPGs). However, the quality of recent urticaria CPGs remains unclear.

OBJECTIVE

To identify and appraise urticaria CPGs worldwide published in the last 5 years.

METHODS

A search for relevant urticaria CPGs was conducted between January 1, 2017, and May 31, 2022, using the following databases: MEDLINE, Embase, National Institute for Health and Care Excellence (NICE) Evidence Search, Guidelines International Network, ECRI Guidelines Trust, Australian Clinical Practice Guidelines, Trip Medical Database, and DynaMed. The included CPGs were critically appraised using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument, Lenzer et al's red flags, and the Institute of Medicine (IOM) criteria of trustworthiness.

RESULTS

We included 21 urticaria CPGs. Most guidelines reviewed treatment recommendations of chronic spontaneous urticaria. The majority of guidelines were from European and Asian countries with high and high-middle sociodemographic index, written in English, and openly accessible. Seventeen guidelines (81%) had at least 1 AGREE II domain rated poor quality. Applicability, rigor of development, and stakeholder involvement were the 3 AGREE II domains that scored the lowest across guidelines. Appraisal with Lenzer et al's red flags showed that 18 guidelines (86%) raised at least 1 red flag indicating potential bias. The top 3 domains raising red flags were: no inclusion of nonphysician experts/patient representative/community stakeholders, no or limited involvement of a methodologist in the evaluation of evidence, and lack of external review. Based on IOM's criteria of trustworthiness, 20 guidelines (95%) had 1 or more criteria that did not meet best practice standards. The 3 domains with the highest number of best practice standards not met were updating procedures, rating strength of recommendations, and external review. Guidelines scored highest for the AGREE II domains of defining scope and purpose and clarity of presentation, and had the most fully met IOM's best practice standard for articulation of recommendations. However, only 1 urticaria CPG by NICE was identified as rigorously developed across all 3 appraisal tools.

CONCLUSIONS

The quality of urticaria CPGs in the last 5 years varied widely. Only the NICE urticaria guideline consistently demonstrated excellent quality, high trustworthiness, and low risk of bias. Use of a rigorous framework to rate certainty of evidence and grade strength of recommendation, involvement of methodologists, stakeholder engagement with external review, and clear guidance for updating can help improve the quality of future CPGs.

COX-2 inhibitors show no preventive effect in the development of skin cancer

BACKGROUND

Some clinical trials found that cyclooxygenase-2 (COX-2) inhibitor use lowered the risk of skin cancer in high-risk groups.

PATIENTS AND METHODS

To determine whether COX-2 inhibitor use is associated with lower risk of basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC), and melanoma, we analyzed COX-2 inhibitor use and risk of skin cancer based on three prospective cohort studies, the Nurses' Health Study (NHS), NHS II, and the Health Professionals Follow-up Study, including 153,882 participants. Multivariable hazard ratios (HRs) and 95 % confidence intervals (CIs) for the association of COX-2 inhibitor use with risk of BCC, cSCC, and melanoma were estimated using Cox proportional hazards models. We pooled the results using a fixed effects model.

RESULTS

16,142 BCC, 1,973 cSCC, and 631 melanoma cases were documented. Ever vs. never use of COX-2 inhibitor was associated with a modestly increased risk of BCC (multivariable HR 1.09, 95 % CI 1.05-1.14). The hazard ratio was similar for cSCC (multivariable HR 1.12, 95 % CI 1.00-1.27) and melanoma (multivariable HR 1.10, 95 % CI 0.89-1.38), but was not statistically significant.

CONCLUSIONS

Ever use of COX-2 inhibitor was not associated with a decreased skin cancer risk but was instead associated with a modest, increased risk of BCC.

Global Guidelines in Dermatology Mapping Project (GUIDEMAP): a scoping review of dermatology clinical practice guidelines

BACKGROUND

Clinical practice guidelines (CPGs) play a critical role in standardizing and improving treatment outcomes based on the available evidence. It is unclear how many CPGs are available globally to assist clinicians in the management of patients with skin disease.

OBJECTIVES

To search for and identify CPGs for dermatological conditions with the highest burden globally.

METHODS

We adapted a list of 12 dermatological conditions with the highest burden from the Global Burden of Disease (GBD) study 2019. A systematic literature search was done to identify CPGs published between October 2014 to October 2019. The scoping review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework.

RESULTS

A total of 226 CPGs were included. Melanoma had the greatest representation in the CPGs, followed by dermatitis and psoriasis. Skin cancers had a relatively high CPG representation but with lower GBD disease burden ranking. There was an uneven distribution by geographical region, with resource-poor settings being under-represented. The skin disease categories of the CPGs correlated weakly with the GBD disability-adjusted life-years metrics. Eighty-nine CPGs did not have funding disclosures and 34 CPGs were behind a paywall.

CONCLUSIONS

The global production of dermatology CPGs showed wide variation in geographical representation, article accessibility and reporting of funding. The number of skin disease CPGs were not commensurate with its disease burden. Future work will critically appraise the methodology and quality of dermatology CPGs and lead to the production of an accessible online resource summarizing these findings.

Abstract 3491: COX-2 inhibitor use and risk of skin cancer: three prospective cohort studies

Skin cancer is the most commonly diagnosed type of cancer, with continually rising incidence rates. Cyclooxygenase-2 (COX-2) inhibitor use has been associated with lower risk of several cancers, though epidemiological studies on skin cancer risk have been limited and inconclusive. To evaluate whether COX-2 inhibitor use is associated with decreased risk of basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC), and melanoma, we analyzed COX-2 inhibitor use and risk of skin cancer based on three prospective cohorts–the Nurses' Health Study (NHS, 2000-2012), NHS II (2001-2011), and the Health Professionals Follow-up Study (HPFS, 2002-2012). COX-2 inhibitor use and duration were assessed by biennial questionnaires, with cSCC and melanoma cases verified by pathological records. Over 1.54 million person-years of follow-up, 16,098 BCC, 1,973 cSCC, and 625 invasive melanoma cases were documented. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of COX-2 inhibitor use with risk of BCC, cSCC, and melanoma were estimated using Cox proportional hazards models. We pooled the results between the three cohorts using a fixed effects model. For ever vs. never users, COX-2 inhibitor use was associated with a modestly increased risk of BCC (multivariable HR 1.10, 95% CI 1.06–1.15) and cSCC (multivariable HR 1.12, 95% CI 1.00–1.27). The effect estimate was similar for melanoma, but was non-significant (multivariable HR 1.10, 95% CI 0.89–1.38). In conclusion, COX-2 inhibitor use was not associated with decreased skin cancer risk and instead was associated with modestly increased risk of BCC and cSCC. Further investigation is necessary to replicate these results.

Citation Format: Hsuan Yen, Hsi Yen, Aaron Drucker, Jiali Han, Wen-Qing Li, Tricia Li, Abrar Qureshi, Eunyoung Cho. COX-2 inhibitor use and risk of skin cancer: three prospective cohort studies [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3491.

Is psoriasis associated with dementia or cognitive impairment? A Critically Appraised Topic

CLINICAL QUESTION

Is psoriasis associated with dementia or cognitive impairment?

BACKGROUND

Psoriasis is a multisystemic inflammatory disorder that has an unclear association with cognitive dysfunction.

OBJECTIVES

To conduct a Critically Appraised Topic that synthesizes the results from relevant observational studies.

METHODS

A systematic literature search of PubMed and Embase was conducted on 12 July 2019 to identify case-control, cross-sectional or cohort studies that investigated the association between psoriasis and cognitive impairment or dementia. Risk of bias was assessed for each study, and the results presented in a narrative synthesis.

RESULTS

Eleven studies were included for critical appraisal. Of the 11 studies, 10 compared a total of 16 574 psoriasis cases with over 45 078 controls for risk of dementia or cognitive impairment. One of the 11 studies evaluated 7118 patients with dementia for odds of psoriasis compared with 21 354 controls. Six studies were assessed to have higher risk of bias. Nine of the 11 included studies found a significant positive association between the two diseases, one study a null association, and one study an inverse association.

DISCUSSION AND RECOMMENDATION

Most of the 11 included studies found a positive association between psoriasis and either mild cognitive impairment or dementia. Brief cognitive assessments have been suggested to screen older patients with psoriasis who present with subjective cognitive complaints.

Association Between Psoriasis and Vitiligo: A Systematic Review and Meta-Analysis

BACKGROUND

The relationship between psoriasis and vitiligo has not been previously confirmed, and we therefore aimed to investigate this association.

METHODS

We conducted a search of the MEDLINE and EMBASE electronic databases on 22 January 2018 for case-control, cross-sectional, and cohort studies examining the association between psoriasis and vitiligo. A customized Newcastle-Ottawa Scale was used to assess the risk of bias of the included studies. We performed a random effects meta-analysis to calculate pooled odds ratios (ORs) with 95% confidence intervals (CIs) for case-control and cross-sectional studies.

RESULTS

Of 2453 citations identified from the literature search, 10 case-control/cross-sectional studies with a total of 120,866 psoriasis cases and 79,907 vitiligo cases were included in our study. Four of these studies were rated as high risk of bias. We found a significantly increased odds for vitiligo in psoriasis patients (summary OR 2.29, 95% CI 1.56-3.37, studies = 7), as well as a significantly elevated odds for psoriasis in vitiligo patients (summary OR 3.43, 95% CI 1.86-6.33, studies = 4).

CONCLUSIONS

Our meta-analysis showed that psoriasis and vitiligo are associated with each other. Several studies had a high risk of bias, and further investigation is needed to confirm this association and amplify treatment options.

All-cause and cause-specific mortality in psoriasis: A systematic review and meta-analysis

BACKGROUND

An overview of mortality risk associated with psoriasis is lacking.

OBJECTIVE

To perform a systematic review and meta-analysis of mortality risk in psoriasis.

METHODS

We included studies reporting all-cause or cause-specific mortality risk estimates in psoriasis patients compared with general population or subjects free of psoriasis. We calculated pooled relative risks (RRs) and 95% confidence intervals (CIs).

RESULTS

We included 12 studies. The pooled RRs for all-cause mortality were 1.21 (95% CI 1.14-1.28) in psoriasis, 1.13 (95% CI 1.09-1.16) in mild psoriasis, and 1.52 (95% CI 1.35-1.71) in severe psoriasis. The pooled RRs for cardiovascular mortality were 1.15 (95% CI 1.09-1.21) in psoriasis, 1.05 (95% CI 0.92-1.20) in mild psoriasis, and 1.38 (95% CI 1.09-1.74) in severe psoriasis. For noncardiovascular causes, mortality risk from liver disease, kidney disease, and infection was significantly increased in psoriasis, regardless of disease severity. The mortality risk in liver and kidney disease was the highest. There was also a significantly increased mortality risk associated with neoplasms in severe psoriasis patients and chronic lower respiratory disease in all and mild psoriasis patients.

LIMITATIONS

Although associations were consistent, their magnitude was heterogenous.

CONCLUSION

Psoriasis is associated with an increased risk for mortality from all causes (in a dose-response manner with disease severity) and from several specific causes.

Serum homocysteine, folate and vitamin B12 levels in patients with psoriasis: a systematic review and meta-analysis

BACKGROUND

Patients with psoriasis are at increased risk for cardiovascular comorbidities. Previous studies examined the possible contribution of serum homocysteine, folate and vitamin B₁₂ to cardiovascular risks in patients with psoriasis but had conflicting conclusions.

OBJECTIVES

To perform a systematic review and meta-analysis of studies on serum homocysteine, folate and vitamin B₁₂ levels in patients with psoriasis.

METHODS

Online databases were searched on 15 February 2018 to include studies comparing serum homocysteine, folate and vitamin B₁₂ levels between patients with psoriasis and controls. A random effects model was adopted to estimate odds ratios for dichotomous data and standardized mean differences (SMDs) for continuous data.

RESULTS

A comprehensive literature search identified 24 studies eligible for inclusion. Compared with controls, patients with psoriasis had a significantly higher serum homocysteine level [SMD 0·41, 95% confidence interval (CI) 0·21-0·61; I² = 76·7%, 18 studies], a higher prevalence of hyperhomocysteinaemia (odds ratio 3·48, 95% CI 2·08-5·83; I² = 41·1%, seven studies) and a lower serum folate level (SMD -0·94, 95% CI -1·49 to -0·40; I² = 95·6%, 14 studies). However, there was no difference in serum vitamin B₁₂ levels between patients with psoriasis and the control group (SMD 0·004, 95% CI -0·49 to 0·50; I² = 92%, 11 studies). Metaregression analysis revealed a significant inverse correlation between the SMD of homocysteine levels and folate levels.

CONCLUSIONS

Patients with psoriasis might have higher serum homocysteine and lower folate levels than control patients without psoriasis. However, due to significant heterogeneity and other limitations, the associations require further examinations in more studies.

Red meat and processed meat intake and risk for cutaneous melanoma in white women and men: Two prospective cohort studies

BACKGROUND

Red and processed meat consumption has been associated with increased risk for several cancers, but the association with cutaneous melanoma risk has been inconclusive.

OBJECTIVE

To investigate the association between red and processed meat intake and melanoma risk.

METHODS

Dietary information was assessed by using food frequency questionnaires in 2 prospective cohorts: 75,263 women from the Nurses' Health Study (1984-2010) and 48,523 men from the Health Professionals Follow-up Study (1986-2010). Melanoma cases were confirmed by reviewing pathology records. Pooled multivariable hazard ratios and 95% confidence intervals were estimated by using Cox proportional hazards models.

RESULTS

A total of 679 female and 639 male melanoma cases were documented during follow-up. Red and processed meat intake was inversely associated with melanoma risk (P = .002 for trend); the pooled hazard ratios (95% confidence intervals) of the 2 cohorts were 1.00 (reference), 1.00 (0.87-1.14), 0.98 (0.86-1.13), 0.89 (0.77-1.02), and 0.81 (0.70-0.95) for increasing quintiles of intake.

LIMITATIONS

Findings might have limited generalizability, considering that the cohorts were limited to white health professionals.

CONCLUSION

Red and processed meat intake was inversely associated with melanoma risk in these 2 cohorts.

Intake of folate and other nutrients related to one-carbon metabolism and risk of cutaneous melanoma among US women and men

BACKGROUND

Nutrients involved in one-carbon metabolism - folate, vitamins B6 and B12, methionine, choline, and betaine - have been inversely associated with multiple cancer sites and may be related to skin cancer. However, there is a lack of research on the association between intake of these nutrients and cutaneous melanoma risk. The aim of this study was to examine the associations between intake of one-carbon metabolism nutrients and cutaneous melanoma risk in two large prospective cohorts.

METHODS

The cohorts included 75,311 white women and 48,523 white men. Nutrient intake was assessed repeatedly by food frequency questionnaires and self-reported supplement use. We used Cox proportional hazards regression to estimate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) and then pooled HRs using a random-effects model.

RESULTS

Over 24-26 years of follow-up, we documented 1328 melanoma cases (648 men and 680 women). Higher intake of folate from food only, but not total folate, was associated with increased melanoma risk (pooled HR for top versus bottom quintile: 1.36; 95% CI: 1.13-1.64; P for trend = 0.001). The association was significant in men, but attenuated in women. Higher intake of vitamins B6 and B12, choline, betaine, and methionine were not associated with melanoma risk, although there was modest increasing trend of risk for vitamin B6 from food only (pooled HR for top versus bottom quintile: 1.18; 95% CI: 0.99-1.41; P for trend = 0.03).

CONCLUSIONS

We found some evidence that higher intake of folate from food only was associated with a modest increased risk of cutaneous melanoma. However, since other factors related to dietary folate intake may account for the observed association, our findings warrant further investigation.

A new mobile learning module using smartphone wallpapers in identification of medical fungi for medical students and residents

INTRODUCTION

Medical students and residents will encounter many cutaneous fungal infections in medical practice. However, the training for identification of medical fungi has been insufficient due to limited lecture-based courses. The objective of this study was to evaluate the impact of using smartphone-based wallpapers in learning the microscopic morphology and colony characteristics of medical fungi for medical students and residents.

METHODS

A smartphone-based wallpaper learning module using a wallpaper-changing software application (app) was introduced in this 3-week training course. Twenty-six participants were enrolled and divided into two groups: nondermatology trainees, including medical students and postgraduate year one (PGY-1) doctors who have not yet specialized, and dermatology trainees (dermatology residents). All of the participants completed a 3-week training course, and the effectiveness of the module was evaluated by pre- and post-course multiple-choice examinations.

RESULTS

Both nondermatology and dermatology trainees scored significantly higher in post-course examinations than pre-course examinations (P < 0.001). The dermatology trainees performed better than nondermatology trainees in the pre-course examinations (P < 0.001). In the post-course examinations, no significant difference in scores was noted between dermatology and nondermatology trainees (P = 0.573).

DISCUSSION

The smartphone-based wallpaper learning module was effective in helping medical students and residents learn and memorize morphologic characteristics of fungi. In comparison to conventional lecture-based learning, this new mobile module was more readily accessible and convenient for learners to engage in learning.

Alcohol intake and risk of nonmelanoma skin cancer: a systematic review and dose-response meta-analysis

Nonmelanoma skin cancer (NMSC) comprises mainly basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC). The association between alcohol intake and NMSC has been inconclusive; therefore the objective of this study is to quantify the relationship between alcohol intake and NMSC using meta-analyses. A systematic literature search of PubMed and Embase was performed on 30 October 2016. Eligible articles were case-control or cohort studies that examined alcohol intake and risk of BCC or cSCC and reported relative risks (RRs) with 95% confidence intervals (CIs). Of the 307 articles identified, 13 case-control and cohort studies were included in the systematic review, including 95 241 NMSC cases (91 942 BCC and 3299 cSCC cases). A random-effects model was used to obtain summary RRs and 95% CIs for dose-response meta-analyses. For every 10-gram increase in ethanol intake per day, a positive association was found for both BCC (summary RR of 1·07; 95% CI 1·04-1·09) and cSCC (summary RR of 1·11; 95% CI 1·06-1·16). While there was evidence suggesting a nonlinear association for BCC, it may be due to the sparse data at higher alcohol intake levels. This meta-analysis found evidence that alcohol drinking is positively associated with both BCC and cSCC risk in a dose-dependent manner. These results should be interpreted with caution due to potential residual confounding. Nonetheless, because alcohol drinking is a prevalent and modifiable behaviour, it could serve as an important public health target to reduce the global health burden of NMSC.

Abstract 5320: Folate and other nutrients related to one-carbon metabolism and risk of melanoma

Background: Nutrients involved in one-carbon metabolism - folate, vitamins B6 and B12, methionine, choline, and betaine - have been associated with multiple cancer sites. However, no study has assessed the association between these nutrients and risk of melanoma. Thus, the aim of this study was to evaluate the association between intake of these nutrients and melanoma risk within two prospective cohorts: the Nurses’ Health Study (NHS) and Health Professionals Follow-up Study (HPFS).

Methods: The cohorts included a total of 81,685 women in the NHS (1984 to 2010) and 49,617 men in the HPFS (1986 to 2010). We assessed nutrient intakes using a semi-quantitative food frequency questionnaire every 2 to 4 years. Total nutrient intake included both dietary and supplemental intake. Dietary intake included intake from food only. Study physicians reviewed medical and pathological records to confirm self-reported cases of invasive melanoma. We used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) and then pooled the HRs for both cohorts using a random effects model.

Results: Over 24 to 26 years of follow-up, we documented 1,321 cases (641 men and 680 women) of invasive melanoma. Higher intake of folate from food only, but not total folate, was associated with increased risk of melanoma. The pooled multivariable HRs for the top versus bottom quintiles were 1.17 (95 % CI: 0.98-1.41; P for trend = 0.17) for total folate and 1.37 (95 % CI: 1.13-1.65; P for trend = 0.001) for folate from food only. The association was statistically significant in men, but not in women. Higher intake of vitamins B6 and B12, choline, betaine, and methionine was not associated with risk of melanoma.

Conclusion: We found some evidence that folate from food only, but not total folate, was associated with a modest increased risk of melanoma - a finding that warrants further investigation. Conversely, our findings suggest that other nutrients involved in one-carbon metabolism do not play an important role in the etiology of melanoma.

Citation Format: Ashar Dhana, Hsi Yen, Tricia Li, Michelle Holmes, Abrar Qureshi, Eunyoung Cho. Folate and other nutrients related to one-carbon metabolism and risk of melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5320. doi:10.1158/1538-7445.AM2017-5320

Correlating 2-MIB and microcystin concentrations with environmental parameters in two reservoirs in South Taiwan

Cyanobacteria are present in many drinking water reservoirs in Taiwan, and some of them may produce off-flavour compounds and natural toxins. To investigate the correlation among two groups of cyanobacterial metabolites, microcystins and 2-methylisoborneol (2-MIB), and other environmental parameters, approximately 22 water quality and meteorological parameters were monitored for two source waters (Moo-Tan and Tseng-Wen reservoirs) in south Taiwan from August 2003 to April 2005. Monitoring results showed that the two groups of cyanobacterial metabolites were present in the source waters. Concentrations of 2-30 ng/L of 2-MIB was observed for the two reservoirs, while that of the total concentrations of the five microcystin congeners measured were between 30 and 340 ng/L. The concentration of both 2-MIB and microcystins showed higher concentrations in warmer seasons. A stepwise regression technique was employed to correlate 2-MIB and microcystins concentrations with all the corresponding water quality and meteorological parameters. Correlations among 2-MIB concentration, microcystin concentration, water temperature and air temperature were found in the water samples collected from both reservoirs. The correlations may provide a simple means for the water utility to anticipate the two groups of cyanobacterial metabolites in the two source waters.

Analysis of the ethylene response in the epinastic mutant of tomato

Ethylene can alter plant morphology due to its effect on cell expansion. The most widely documented example of ethylene-mediated cell expansion is promotion of the "triple response" of seedlings grown in the dark in ethylene. Roots and hypocotyls become shorter and thickened compared with controls due to a reorientation of cell expansion, and curvature of the apical hook is more pronounced. The epinastic (epi) mutant of tomato (Lycopersicon esculentum) has a dark-grown seedling phenotype similar to the triple response even in the absence of ethylene. In addition, in adult plants both the leaves and the petioles display epinastic curvature and there is constitutive expression of an ethylene-inducible chitinase gene. However, petal senescence and abscission and fruit ripening are all normal in epi. A double mutant (epi/epi;Nr/Nr) homozygous for both the recessive epi and dominant ethylene-insensitive Never-ripe loci has the same dark-grown seedling and vegetative phenotypes as epi but possesses the senescence and ripening characteristics of Never-ripe. These data suggest that a subset of ethylene responses controlling vegetative growth and development may be constitutively activated in epi. In addition, the epi locus has been placed on the tomato RFLP map on the long arm of chromosome 4 and does not demonstrate linkage to reported tomato CTR1 homologs.

Fine-needle aspiration of a metaplastic breast carcinoma with extensive melanocytic differentiation: a case report

Metaplastic carcinomas of the breast are uncommon breast tumors with aberrant cellular differentiation, most commonly showing ductal, squamous, and mesenchymal components. A breast carcinoma composed of both epithelial and melanocytic differentiation is rare, with only four previously reported cases in the literature. We present the fifth reported case, where the diagnosis was suggested by fine-needle aspiration (FNA) and later confirmed after the surgical specimen was excised. Histologically, this neoplasm revealed multidirectional differentiation, consisting primarily of squamous and melanocytic cell types, with focal glandular and osseous metaplasia. Based on the morphologic, immunohistochemical, and ultrastructural findings, we conclude that such tumors fall within the spectrum of metaplastic carcinomas of the breast. We believe that this case will further contribute to the understanding of this enigmatic tumor.

[Karyotype analysis of Carpesium cernuum]

The paper reported the chromosome number, karyotype and chromosome volume of Carpesium cernuum. The normal diploid was 2n = 40, karyotype formula based on Levan's publication was k(2n) = 40 = 24 m + 12 sm + 2 st + 2T. According to the method of S. R. Kuo, the chromosome relative length was 2n = 40 = 8L + 6M2 + 16M1 + 10S, which belong to "2B" type according to the Stebbins' karyotype classification. The AS.K% was 62.35% from Arano's method. The total volume of chromosome groups was 13.76 microns 3.

Retroperitoneal ganglioneuroma: a report of diagnosis by fine-needle aspiration cytology

Ganglioneuroma is a rare benign tumor composed of nerve fibers and mature ganglion cells. Because it shares morphologic features with other neural tumors, both benign and malignant, accurate preoperative diagnosis is often difficult, but nonetheless, critical for proper management. The use of fine-needle aspiration (FNA) cytology in the diagnosis of ganglioneuroma has been rarely documented. In this report, a 25-yr-old man presented with a large retroperitoneal ganglioneuroma that was initially diagnosed by FNA cytology. This case illustrates the utility of FNA cytology in the diagnosis of ganglioneuroma and supports the routine incorporation of FNA cytology in the evaluation of retroperitoneal masses.

[Karyotype analysis on Iris lactea ssp. chinensis]

In this paper, the chromosome number, karyotype and chromosome volume of Iris lactea ssp. chinensis were reported. The normal diploid was 2n = 32. Karyotype formula was based on Levan's publication in 1964, k (2n) = 32 = 22 m + 8 sm + 2T. According to the method of Kuo SR, the species chromosome based on the relative length was 2n = 32 = 6L + 4 M2 + 18 M1 + 4 S which belong to "2A" type according to the Stebbins' karyotype classification. The AS.K% was 62.5% from Arano's method. The total volume of chromosome groups was 34.95 micron 3.

Amino acid residues in both the protein splicing and endonuclease domains of the PI-SceI intein mediate DNA binding

A structure-based model describing the interaction of the two-domain PI-SceI endonuclease with its 31-base pair DNA substrate suggests that the endonuclease domain (domain II) contacts the cleavage site region of the substrate, while the protein splicing domain (domain I) interacts with a distal region that is sufficient for high affinity binding. To support this model, alanine-scanning mutagenesis was used to assemble a set of 49 PI-SceI mutant proteins that were purified and assayed for their DNA binding and cleavage properties. Fourteen mutant proteins were 4- to >500-fold less active than wild-type PI-SceI in cleavage assays, and one mutant (T225A) was 3-fold more active. Alanine substitution at two positions in domain I reduces overall binding >60-fold by perturbing the interaction of PI-SceI with the minimal binding region. Conversely, mutations in domain II have little effect on binding, reduce binding to the cleavage site region only, or affect binding to both regions. Interestingly, substitutions at Lys301, which is part of the endonucleolytic active site, eliminate binding to the cleavage site region but permit contact with the minimal binding region. This experimental evidence demonstrates that the protein splicing domain as well as the endonuclease domain is involved in binding of a DNA substrate with the requisite length.

MCP-1-mediated chemotaxis requires activation of non-overlapping signal transduction pathways

Monocyte chemoattractant protein-1 (MCP-1) is a CC chemokine that attracts monocytes and T lymphocytes. Its receptor (CCR2) is a heptahelical G-protein-coupled receptor (GPCR) whose signal transduction pathways for chemotaxis have not been completely defined. Because other GPCRs stimulate the mitogen-activated protein kinase (MAPK) cascade, we examined this pathway's activity in response to MCP-1. MCP-1 induced rapid and transient activation of MAPK in human monocytes and in Chinese hamster ovary cells expressing CCR2B. This effect was largely insensitive to pertussis toxin and wortmannin, and was protein kinase C-dependent and protein tyrosine kinase-independent. PD 098059, an inhibitor of MEK activation, not only prevented MAPK activation but also inhibited MCP-1-induced chemotaxis. Because pertussis toxin and wortmannin also efficiently inhibit chemotaxis but do not completely inhibit MAPK activation, these data may define non-overlapping signal transduction pathways that all must be activated to produce chemokine-mediated chemotaxis.

[An immunocytochemical study of neuropeptide-like in a ciliated protozoan, Stylonychia mytilus]

An immunocytochemical investigation with both B-SA and ABC methods, under LM and EM, was carried out on Stylonychia mytilus by using 7 antisera to vertebrate neuropeptides, hormones and TH. The immunotests showed the presence of substance p-, neuropeptide y-, cck-8-, somatostatin-, beta-endorphin, adrenocorticotropic hormone-, and TH-like immunoreactive molecules in Stylonychia mytilus. The distributions of these immunoreactive substances in Stylonychia mytilus were described.

On-line sensors for coagulation proteins: concept and progress report

The assessment of blood damage and of the activation of the coagulation, complement and/or inflammatory systems by cardiovascular and extracorporeal devices is difficult at best. Immunoassay methods are now available for the measurement of many of the proteins, enzymes and peptides involved in coagulation, thrombosis, complement and inflammation. We present a long-range project and plan to develop an array of remote, on-line, semicontinuous immunosensors for selected coagulation proteins, based on fluoroimmunoassay principles. The free/bound separation step is performed optically. Excitation of fluorescence is performed via an evanescent wave produced by total internal reflection and waveguide optics. Fluorescence emission is collected only in the near field. Means to deliver fluorescently-labelled reagent and to modify the antigen-antibody binding constant are presented and discussed. The results of non-specific binding, plasma-blood fluorescence, and blood compatibility are also discussed.

Uterine contractility and oxytocin sensitivity in preterm, term, and postterm pregnancy

The records of 117 patients who had serial nonstress tests (N = 285) and oxytocin challenge tests (N = 268) were analyzed to determine whether baseline uterine contractility and/or oxytocin sensitivity changed with increasing gestational age. The results obtained in patients who were delivered before, at, and after term were compared. Uterine contractility and oxytocin sensitivity increased in all groups as gestational age progressed. No significant differences in uterine contractility were noted among groups; however, oxytocin sensitivity was significantly increased in the preterm group (p less than 0.001) and decreased in the postterm group (p less than 0.001). Our results suggest that the response of the uterus to oxytocin early in pregnancy may help to identify patients who will be delivered before or after term.