Usefulness and Limitations of PFGE Diagnosis and Nucleotide Sequencing Method in the Analysis of Food Poisoning Pathogens Found in Cooking Employees

In the case of a food poisoning outbreak, it is essential to understand the relationship between cooking workers and food poisoning. Many biological diagnostic methods have recently been developed to detect food poisoning pathogens. Among these diagnostic tools, this study presents PCR-based pulsed-field gel electrophoresis and nucleotide sequencing diagnostic analysis results for diagnosing food poisoning outbreaks associated with cooking employees in Chungcheongnam-do, Republic of Korea. Pulsed-field gel electrophoresis was useful in identifying the food poisoning outbreaks caused by Staphylococcus aureus and Enteropathogenic Escherichia coli. In the case of Norovirus, nucleotide sequencing was used to identify the relationship between cooking workers and the food poisoning outbreak. However, it is difficult to determine whether cooking employees directly caused the food poisoning outbreaks based on these molecular biological diagnostic results alone. A system is needed to integrate epidemiological and diagnostic information to identify a direct correlation between the food poisoning outbreak and cooking employees.

A simplified cranial cavity model to understand the relationship between intracranial pressure and dural sinus pressure

Although accurate intracranial pressure (ICP) monitoring is essential for the diagnosis and treatment of severe brain diseases, current methods are performed invasively. Therefore, a safe and less invasive ICP measurement is required. The purpose of our study was to develop a simplified cranial cavity model for a better understanding of the relationship between the ICP and the pressure measurement within the dural venous sinus (DVS) to support the validity of using sinus pressure as the surrogate of the ICP. The in-house cranial cavity model had three components: the brain part, the DVS part, and the subarachnoid space (SAS) part. Pressure in other parts was measured when the pressure in the SAS part and, separately, brain part was increased from 0 (baseline) to 50 mmHg at intervals of 10 mmHg. When the pressure in the SAS part was increased from 10 to 50 mmHg at 10 mmHg interval, pressures of both the brain and DVS parts increased without significant difference (all P > 0.05). However, pressures in both the SAS and DVS parts differed while the pressure in the brain part was increased. The pressures in both parts showed about 70% of the increase in the brain part. Nevertheless, the pressures in the SAS and DVS parts were not significantly different (P > 0.05). A simplified in-house cranial cavity model was developed consisting of three compartments to represent the actual intracranial spaces. The pressure measurement within the DVS was feasible to use as a surrogate for the ICP measurement.

Validity of Rapid Antibody Testing for COVID-19 Vaccine in Homeless People

(1) Background: There is a paucity of data regarding the validity of rapid antibody testing for SARS-CoV-2 vaccine response in homeless people worldwide. The objective of this study was to evaluate a rapid SARS-CoV-2 IgM/IgG antibody detection kit as a qualitative screen for vaccination in homeless people. (2) Methods: This study included 430 homeless people and 120 facility workers who had received one of BNT162b2, mRNA-1273, AZD1222/ChAdOx1, or JNJ-78436735/AD26.COV2.5 vaccines. They were tested for IgM/IgG antibodies to the SARS-CoV-2 spike protein with the STANDARD™ Q COVID-19 IgM/IgG Plus Test (QNCOV-02C). ELISA/competitive inhibition ELISA (CI-ELISA) was subsequently run to assess the validity of the serological antibody test. (3) Results: The sensitivity of homeless people was 43.5%. The status of homelessness was related to a lower agreement between serological antibody testing and CI-ELISA (adjusted OR (aOR), 0.35; 95% CI, 0.18-0.70). However, the Heterologous boost vaccine presented higher agreement between serological antibody testing and CI-ELISA (adjusted OR (aOR), 6.50; 95% CI, 3.19-13.27). (4) Conclusions: This study found weak agreement between the rapid IgG results and confirmatory CI-ELISA testing in homeless people. However, it can be used as a screening test for the acceptance of homeless people with heterologous boost vaccination in facilities.

The impact of the COVID-19 pandemic on chlamydia infection in South Korea: a comparison between the pre-pandemic and during-pandemic periods

Background

Prior to COVID-19 pandemic, a yearly upward trajectory in the number of chlamydia infection cases was observed in South Korea. However, in response to the COVID-19 pandemic, Korea implemented several public health and social measures, which were shown to have an impact on the epidemiology of other infectious diseases. This study aimed to estimate the impact of the COVID-19 pandemic on the incidence and number of reported chlamydia infections in South Korea.

Methods

Using the monthly number of reported chlamydia infection data between 2017 and 2022, we compared the trends in the reported numbers, and the incidence rates (IR) of chlamydia infection stratified by demographic characteristics (sex, age group, and region) in the pre- and during COVID-19 pandemic period (January 2017-December 2019 and January 2020-December 2022).

Results

We observed an irregular downward trajectory in the number of chlamydia infection in the during-pandemic period. A 30% decrease in the total number of chlamydia infection was estimated in the during-pandemic compared to the pre-pandemic period, with the decrease greater among males (35%) than females (25%). In addition, there was a decrease in the cumulative incidence rate of the during COVID-19 pandemic period (IR: 0.43; 95% CI: 0.42-0.44) compared to the pre-pandemic period (IR: 0.60; 95% CI: 0.59-0.61).

Conclusions

We identified decrease in the number of chlamydia infection during COVID-19 pandemic which is likely due to underdiagnosis and underreporting for the infection. Therefore, strengthening surveillance for sexually transmitted infections including chlamydia is warranted for an effective and timely response in case of an unexpected rebound in the number of the infections.

Clinical and Laboratory Findings of Middle East Respiratory Syndrome Coronavirus Infection

There is a paucity of data regarding the differentiating characteristics of patients with laboratory-confirmed and those negative for Middle East respiratory syndrome coronavirus (MERS-CoV) in South Korea. This hospital-based retrospective study compared MERS-CoV-positive and MERS-CoV-negative patients. A total of seven positive patients and 55 negative patients with a median age of 43 years (P = 0.845) were included. No statistical differences were observed with respect to their sex and the presence of comorbidities. At the time of admission, headache (28.6% vs. 3.6%; odds ratio [OR], 10.60; 95% confidence interval [CI], 1.22-92.27), myalgia (57.1% vs. 9.1%; OR, 13.33; 95% CI, 2.30-77.24), and diarrhea (57.1% vs. 14.5%; OR, 7.83; 95% CI, 1.47-41.79) were common among MERS-CoV-positive patients. MERS-CoV-positive patients were more likely to have a low platelet count (164 ± 76.57 vs. 240 ± 79.87) and eosinophil (0.27 ± 0.43 vs. 2.13 ± 2.01; P = 0.003). Chest radiography with diffuse bronchopneumonia was more frequent in MERS-CoV-positive patients than in negative patients (100% vs. 62.5%; P = 0.491). The symptoms of headache, myalgia, and diarrhea, as well as laboratory characteristics, including low platelet counts and eosinophil, and chest X-ray showing diffuse bronchopneumonia might enhance the ability to detect patients in South Korea infected with MERS-CoV.

Lysophosphatidylserine receptor P2Y10: A G protein-coupled receptor that mediates eosinophil degranulation

BACKGROUND

P2Y10, along with GPR34 and GPR174, is a G protein-coupled receptor that is activated by an endogenous lipid mediator lysophosphatidylserine (LysoPS). Its expression pattern and its function are completely unknown. We have previously shown that P2Y10 is one of the highly up-regulated genes at the late differentiation stage during in vitro eosinophilopoiesis.

OBJECTIVE

We explored the expression and functions of P2Y10 in human cord blood (CB)-derived and peripheral blood (PB) eosinophils.

METHODS

Real-time PCR, FACS, Western blot, ELISA, and chemotaxis assays were performed to determine the expression and function of P2Y10.

RESULTS

As CB cells differentiated towards eosinophils, P2Y10 mRNA and protein were abundantly expressed. P2Y10 was the most highly expressed in the granulocytes from PB, to a lesser extent in monocytes, and least in lymphocytes. Further fractionation of granulocytes revealed that eosinophils express P2Y10 much more strongly than do neutrophils. PB eosinophils solely expressed P2Y10 among the three LysoPS receptors, while PB neutrophils expressed the three at comparable levels. LysoPS activated both CB and PB eosinophils to induce a robust ERK phosphorylation. Importantly, LysoPS was capable of triggering degranulation of ECP in PB eosinophils. This response was significantly reduced by pharmacological inhibitors of TNF-alpha-converting enzyme (TACE), epidermal growth factor receptor (EGFR), and ERK1/2, which were known to be required in P2Y10-mediated signalling pathways. However, LysoPS had no effect on chemotaxis, differentiation, or eosinophil survival.

CONCLUSIONS AND CLINICAL RELEVANCE

LysoPS provokes eosinophil degranulation through P2Y10. Therefore, P2Y10 is a potential therapeutic target to control eosinophil-associated diseases.

Predictors of job satisfaction and burnout among tuberculosis management nurses and physicians

OBJECTIVES

This study examined job satisfaction, empowerment, job stress, and burnout among tuberculosis management nurses and physicians in public healthcare institutions.

METHODS

This was a cross-sectional study analyzing survey data collected from 249 nurses and 57 physicians in 105 public health centers, three public tuberculosis hospitals, and one tertiary hospital. The survey questionnaire comprised general characteristics, work-related characteristics, and four index scales (job satisfaction, empowerment, job stress, and burnout). The two-sample t-test was used to estimate the mean differences in the four index scales. Multiple regression analysis was used to determine whether general and work-related characteristics affected the four index scales.

RESULTS

The job satisfaction and empowerment scores of the nurses were lower than those of the physicians. Except for the tuberculosis-specialized hospitals alone, the average job satisfaction scores of nurses were higher than those of physicians. Moreover, the nurses reported more job stress and burnout than did the physicians in tuberculosis departments in public healthcare institutions in Korea; in particular, the burnout reported by nurses was significantly higher than that reported by physicians at the National Medical Center. Marital status, nursing position, number of coworkers, the average number of days of overtime work per month, self-rated health, and hospital type were associated with the four index scales.

CONCLUSIONS

Overall, nurses were more vulnerable to job stress and burnout than physicians. Reducing the workload of nurses by ensuring the presence of sufficient nursing staff and equipment, as well as by equipping facilities to prevent tuberculosis infections, should be considered priorities.

Assessing the impact of meteorological factors on malaria patients in demilitarized zones in Republic of Korea

Background

The trend of military patients becoming infected with vivax malaria reemerged in the Republic of Korea (ROK) in 1993. The common explanation has been that infective Anopheles mosquitoes from the Democratic People’s Republic of Korea have invaded Republic of Korea’s demilitarized zone (DMZ). The aim of this study was to verify the relationship between meteorological factors and the number of malaria patients in the military in this region.

Methods

The authors estimated the effects of meteorological factors on vivax malaria patients from the military based on the monthly number of malaria cases between 2006 and 2011. Temperature, precipitation, snow depth, wind velocity, relative humidity, duration of sunshine, and cloud cover were selected as the meteorological factors to be studied. A systematic pattern in the spatial distribution of malaria cases was assessed using the Moran’s Index. Granger causality tests and cross-correlation coefficients were used to evaluate the relationship between meteorological factors and malaria patients in the military.

Results

Spatial analysis revealed significant clusters of malaria patients in the military in Republic of Korea in 2011 (Moran’s I = 0.136, p-value = 0.026). In the six years investigated, the number of malaria patients in the military in Paju decreased, but the number of malaria patients in the military in Hwacheon and Chuncheon increased. Monthly average, maximum and minimum temperatures; wind velocity; and relative humidity were found to be predicting factors of malaria in patients in the military in Paju. In contrast, wind velocity alone was not able to predict malaria in Hwacheon and Chuncheon, however, precipitation and cloud cover were able to predict malaria in Hwacheon and Chuncheon.

Conclusions

This study demonstrated that the number of malaria patients in the military is correlated with meteorological factors. The variation in occurrence of malaria cases was principally attributed to differences in meteorological factors by regions of Republic of Korea.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0111-3) contains supplementary material, which is available to authorized users.

Metastatic renal cell carcinoma mimicking diverticulitis in a patient with chronic lymphocytic leukaemia

We present an unusual case of metastatic renal cell carcinoma (RCC) mimicking diverticulitis in a 76-year-old man with a 16-year history of chronic lymphocytic leukaemia (CLL) and a 2 cm left renal mass. The patient presented with severe abdominal pain and lower gastrointestinal bleeding with anticoagulation from recent pulmonary embolism. His clinical course was troubled by recurrent hospitalisations and complications that delayed investigations and potential treatments. Radiographic findings revealed stable CLL, mild sigmoid diverticulitis and a small renal mass. Small renal masses (less than 4 cm) are considered low risk for metastasising and are, thus, often observed or ablated, rather than resected. Furthermore, gastrointestinal metastases from RCC are rare. This case adds new perspective to the unpredictable nature of RCC and how synchronous malignancies may be masked in patients with long-standing CLL.

Identification of novel mutations in the VPS33B gene involved in arthrogryposis, renal dysfunction, and cholestasis syndrome

Arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome is an autosomal recessive disorder caused by mutations in the VPS33B and VIPAS39. Here, we report novel mutations identified in four patients with ARC syndrome. We analyzed the entire coding regions of the VPS33B and VIPAS39 genes by direct sequencing. To detect novel splice site mutations, mRNA transcripts were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. All four patients had compound heterozygous variants in the VPS33B gene. One patient had a previously reported splice site variant with unknown significance, c.239+5G>A, and a novel nonsense mutation, c.621G>A. The other three patients had the c.403+2T>A mutation, and each of them carried one of the splice site variants, c.239+5G>A or c.499-11G>A. c.239+5G>A and c.499-11G>A created novel splice sites which resulted in abnormal transcripts. No significant VIPAS39 mutation was detected in all patients. In patients suspected with ARC syndrome, mutation analysis of the VPS33B gene should be employed as a primary diagnostic test before performing invasive testing procedures such as organ biopsies. Performing mRNA analysis can be useful in predicting the pathogenic phenotype when the mutation seems to affect a normal splicing mechanism.

Implementation and results of a survey on safe community programs in Gangbuk-gu, Korea: focusing on participants at a local public health center

OBJECTIVES

The purpose of this study was to investigate the current status of and problems with the Safe Community Programs in Gangbuk-gu, one of the 25 districts of the capital city of Korea.

METHODS

The study subjects were 396 individuals who were involved in Safe Community Programs between 2009 and 2011. We examined the effectiveness and willingness of respondents to participate as a safety leader of the Safe Community Program with a questionnaire. We examined the injury death rates of Gangbuk-gu by using of the death certificate data of Korea's National Statistical Office. Descriptive statistics and chi-squared tests were used.

RESULTS

The effectiveness of programs did not differ but active participation differed significantly among subjects (p<0.05). The injury death rate of Gangbuk-gu as a whole increased during the implementation period. However, senior safety, in particular, may be a helpful program for reducing injuries in Gangbuk-gu.

CONCLUSIONS

This study suggests that the lack of active participation may be a major problem of Safe Community Programs in Gangbuk-gu. Therefore, Safe Community Programs should be expanded to the entire district of Gangbuk-gu and more active participation programs should be developed.

Usefulness of plasma epigenetic changes of five major genes involved in the pathogenesis of colorectal cancer

PURPOSE

The purpose of present study was to investigate the methylation status of the promoter region in five genes (mothers against decapentaplegic homolog 4, fragile histidine triad protein, death-associated protein kinase 1, adenomatous polyposis coli (APC), and E-cadherin), which are known to be involved in the pathogenesis of colorectal cancer (CRC) and its clinicopathological significance.

METHODS

The study subjects were 60 CRC patients, 40 patients with adenomatous colorectal polyp and 60 healthy control individuals. We further enrolled a total of 16 patients (two patients with Crohn's disease, two patients with ulcerative colitis, one patient with serrated adenoma, and 11 patients with colorectal cancer). The methylation states of the five genes were determined in peripheral blood plasma using methylation-specific polymerase chain reaction single-strand conformation polymorphism analysis.

RESULTS

This study showed the most sensitive epigenetic markers, E-cadherin (60 %), followed by APC (57 %), for detecting CRC. E-cadherin and APC had similar specificities and amplified 84 and 86 %, respectively, of CRC patients compared to non-CRC patients. Additionally, APC was the only marker to be significantly increased (OR = 6.67, 95 % CI = 1.19-23.4, P = 0.045) and the most sensitive (57 %) and specific (89 %) marker in stage I CRC. Though we have not examined the paired cancer tissues and plasma, there was relatively high concordant rate (60-80 %) in our limited number of colorectal cancer patients.

CONCLUSIONS

Five genes, promoter methylation, in plasma were statistically significant risk factors in CRC patients. In this study, E-cad and APC genes may be particularly useful epigenetic biomarkers in plasma for the detection of CRC. Additionally, APC may able to identify early potential CRC.

Comparison of the adverse events associated with MF59-adjuvanted and non-adjuvanted H1N1 vaccines in healthy young male Korean soldiers

The first large-scale outbreaks of respiratory disease in the 21st century were caused by the influenza A (H1N1) virus in 2009, which affected mostly young adults. The M59 vaccine was developed to control pandemic influenza A (H1N1). However, the complications arising from the use of the non-adjuvanted and adjuvanted vaccines in young male Korean soldiers have not previously been evaluated and compared. We conducted a prospective multicenter study of 2,864 healthy male soldiers aged 19 to 25 years to evaluate the adverse events associated with both the MF59-adjuvanted and non-adjuvanted forms of the influenza A/California/2009 (H1N1) surface-antigen vaccine. In most cases, the adverse-event symptoms were mild, and the most frequent adverse events were swelling at the injection site and myalgia, which were noted in 4.8% and 10.7% of participants, respectively. Administration of the MF59-adjuvanted vaccine was associated with an increased incidence of local (crude odds ratio [cOR], 1.56; 95% confidence interval [CI], 1.11-2.29) and systemic adverse events (cOR, 1.64; 95% CI, 1.29-2.07) after vaccination. Atopic dermatitis (adjusted OR [aOR], 2.32; 95% CI, 0.99-5.46) might be the choice risk factor for local adverse events, and adjuvant use (aOR, 1.35; 95% CI, 1.03-1.78) was a significant predictor of systemic adverse events in healthy young male Korean soldiers.

The positive association between peripheral blood cell counts and bone mineral density in postmenopausal women

PURPOSE

Accumulating evidence has shown a close connection between hematopoiesis and bone formation. Our aim was to evaluate the association between peripheral blood cell counts and bone mineral density (BMD) in a sample of postmenopausal women.

MATERIALS AND METHODS

Three hundreds thirty eight healthy postmenopausal women who underwent BMD measurement during their health check-up were investigated. BMD was measured by dual energy X-ray asorptiometry at L1-L4 spine, femoral neck and total proximal femur. BMD was expressed as a T-score: among T-scores obtained from three different sites (L1-L4 spine, femoral neck and total proximal femur), the lowest T-score was considered to be the subject's T-score.

RESULTS

The prevalence of osteopenia and osteoporosis diagnosed by T-score in the study participants were 49.4% (167/338) and 5.0% (17/338), respectively. Peripheral blood white blood cell (WBC), red blood cell (RBC) and platelet counts had significant positive correlations with T-scores (p<0.001) upon simple linear regression analysis. A multiple linear regression analysis, after controlling of confounders including age, body weight, systolic blood pressure, alkaline phosphatase and creatinine, showed that WBC (β=0.127; standard error=0.043; p=0.014), RBC (β=0.192; standard error=0.139; p<0.001) and platelet (β=0.097; standard error=0.001; p=0.050) counts still had significant positive association with T-scores.

CONCLUSION

The study results showed a positive relationship between blood cell counts and bone mineral density in postmenopausal women, supporting the idea of a close connection between hematopoiesis and bone formation. The study results also suggest that blood cell counts could be a putative marker for estimating BMD in postmenopausal women.

Elevated peripheral blood monocyte fraction in nonalcoholic fatty liver disease

An elevated white blood cell (WBC) count is associated with nonalcoholic fatty liver disease (NAFLD); however, a leukocyte subtype that is involved in the pathogenesis of NAFLD is not known. This study was conducted to investigate the association between NAFLD and WBC subtype fractions (%) among healthy elderly Koreans. A total of 794 subjects who underwent a health check-up were investigated. After excluding excessive alcohol intake and other liver diseases, NAFLD was diagnosed based on sonographic findings: hyperechogenecity of liver tissue, difference of echogenicity between liver and kidney, and visibility of vascular structures. The prevalence of NAFLD among entire cohort was 39.0% (310/794). The presence of NAFLD was significantly associated with higher blood WBC counts (5,485 ± 1073 vs. 5,230 ± 995 per mm(3), p = 0.001) and monocyte fraction (6.08 ± 2.40% vs. 5.12 ± 1.31%, p < 0.001). The multiple logistic regression analysis, after controlling confounders, including age, gender, body mass index, systolic and diastolic blood pressure, fasting blood glucose, alanine aminotransferase, triglyceride, and high-density lipoprotein cholesterol, showed that the prevalence risk of NAFLD was increased significantly according to the monocyte fraction quartiles: odds ratios (ORs) and 95% confidence intervals (CIs) for NAFLD were 1.00, 2.75 (1.63-4.62), 2.84 (1.67-4.84) and 5.17 (3.03-8.83), respectively. There were no significant associations between NAFLD and the total WBC count quartiles in this model. These results indicate that the elevated peripheral blood monocyte fraction is associated with NAFLD. The monocyte fraction might be a useful marker for NAFLD.

A decline in renal function is associated with loss of bone mass in Korean postmenopausal women with mild renal dysfunction

This study was conducted to assess the relationship between estimated glomerular filtration rate (eGFR) and bone mineral density (BMD) in Korean postmenopausal women with mild renal dysfunction. A total of 328 postmenopausal women who underwent BMD measurement during health check-up was investigated. BMD was measured in lumbar spine (L1-L4), femoral neck, total proximal femur and femoral trochanteric areas by dual energy radiography absorptiometry and renal function was estimated by eGFR using Cockcroft-Gault equation. Of the 328 subjects, 317 (96.6%) had an eGFR ≥60 mL/min/1.73 m(2). By using simple linear regression analysis, age, height, weight and eGFR were significantly associated with BMD for the 4 aforementioned anatomic sites, while serum levels of creatinine and blood urea nitrogen did not influence BMD. When multiple regression analyses were applied, age and body weight still had significant associations with BMD at 4 different anatomic sites (P < 0.001). A significant association of eGFR with BMD remained in the lumbar spine, femoral neck and proximal total femur (P < 0.05) but not in the trochanteric area (P = 0.300). Our study suggests that a decline of renal function is associated with lower BMD in the lumbar spine, femoral neck and total proximal femur areas in Korean menopausal women with mild renal dysfunction.

The adverse events of influenza A (H1N1) vaccination and its risk factors in healthcare personnel in 18 military healthcare units in Korea

In this study, we characterized adverse events related to influenza A (H1N1) vaccination and studied the factors that influence the occurrence of these events. A total of 4,302 personnel in 18 military healthcare units in Korea received 0.5 ml of inactivated H1N1 vaccine. The study questionnaires were answered by 3,939 (91.6%) personnel, at both 2 weeks and 4 weeks after vaccination. Among these subjects, 3,531 (82.1%) who responded to all questions in the questionnaire were studied. After immunization, military doctors were ordered to report the occurrence of any adverse event related to the vaccine for 2 months. According to the responses of the subjects, the most prevalent events were fatigue (11.3%), pain at the injection site (8.38%), and myalgia (6.97%). Female gender, being in the age range of 20-49 years, obesity, regular alcohol consumption, and comorbidity, but not smoking status or pregnancy, were related to a high incidence of local or systemic adverse events after H1N1 vaccination. A total of 14 cases of adverse events were reported by the military doctors. In most reported cases, the subjects had fever in addition to the primary adverse event, and one patient was diagnosed with pneumonia. In conclusion, the overall burden of adverse events related to influenza A (H1N1) vaccination was not inconsequential, but most symptoms were mild. Female gender, middle-age range of 20-49 years, obesity, regular alcohol consumption, and comorbidity were risk factors for the occurrence of adverse events after H1N1 vaccination.

[Usefulness of comorbidity indices in operative gastric cancer cases]

OBJECTIVES

The purpose of the current study was to evaluate the usefulness of the following four comorbidity indices in gastric cancer patients who underwent surgery: Charlson Comorbidity Index (CCI), Cumulative Illness rating scale (CIRS), Index of Co-existent Disease (ICED), and Kaplan-Feinstein Scale (KFS).

METHODS

The study subjects were 614 adults who underwent surgery for gastric cancer at K hospital between 2005 and 2007. We examined the test-retest and inter-rater reliability of 4 comorbidity indices for 50 patients. Reliability was evaluated with Spearman rho coefficients for CCI and CIRS, while Kappa values were used for the ICED and KFS indices. Logistic regression was used to determine how these comorbidity indices affected unplanned readmission and death. Multiple regression was used for determining if the comorbidity indices affected length of stay and hospital costs.

RESULTS

The test-retest reliability of CCI and CIRS was substantial (Spearman rho=0.746 and 0.775, respectively), while for ICED and KFS was moderate (Kappa=0.476 and 0.504, respectively). The inter-rater reliability of the CCI, CIRS, and ICED was moderate (Spearman rho=0.580 and 0.668, and Kappa=0.433, respectively), but for KFS was fair (Kappa=0.383). According to the results from logistic regression, unplanned readmissions and deaths were not significantly different between the comorbidity index scores. But, according to the results from multiple linear regression, the CIRS group showed a significantly increased length of hospital stay (p<0.01). Additionally, CCI showed a significant association with increased hospital costs (p<0.01).

CONCLUSIONS

This study suggests that the CCI index may be useful in the estimation of comorbidities associated with hospital costs, while the CIRS index may be useful where estimatation of comorbiditie associated with the length of hospital stay are concerned.

Differential expression of a WD protein during squamous differentiation of tracheal epithelial cells

The lining of the trachea consists of a pseudostratified, mucociliary epithelium that under a variety of conditions, such as vitamin A deficiency, toxic and mechanical injury, becomes a stratified squamous epithelium. Several in vitro cell culture models have been established to study the process of differentiation of airway epithelium. Such studies have indicated that mucosecretory differentiation of tracheal epithelial cells can be modulated by substratum. This study was undertaken to understand molecular mechanisms of squamous differentiation in tracheal epithelia. Primary cultured tracheal cells grown on uncoated filters were differentiated to single layer of squamous cells, whereas cells were grown as stratified columnar cells on collagen-I coated filters. The responses to secretagogues were altered according to culture conditions. DD-PCR revealed that FAK and a WD protein expression was increased in squamous tracheal epithelia. Expression of a WD protein was changed by the treatment of retinoic acid in various epithelial cells. These results indicated that squamous differentiation of tracheal cells changes the expression of a variety of genes, and that the experimental model for this study can be employed to study molecular mechanisms of squamous differentiation in airway epithelial cells.

A potent small molecule, nonpeptide inhibitor of cathepsin K (SB 331750) prevents bone matrix resorption in the ovariectomized rat

Inhibition of the cyteine proteinase, cathepsin K (E.C. 3.4.22.38) has been postulated as a means to control osteoclast-mediated bone resorption. The preferred animal models for evaluation of antiresorptive activity are in the rat. However, the development of compounds that inhibit rat cathepsin K has proven difficult because the human and rat enzymes differ in key residues in the active site. In this study, a potent, nonpeptide inhibitor of rat cathepsin K (K(i) = 4.7 nmol/L), 5-(2-morpholin-4-yl-ethoxy)-benzofuran-2-carboxylic acid ((S)-3-methyl-1-(3-oxo-1-[2-(3-pyridin-2-yl-phenyl)-ethenoyl]-azepan-4-ylcarbanoyl)-butyl)-amide (SB 331750), is described, which is efficacious in rat models of bone resorption. SB 331750 potently inhibited human cathepsin K activity in vitro (K(i) = 0.0048 nmol/L) and was selective for human cathepsin K vs. cathepsins B (K(i) = 100 nmol/L), L (0.48 nmol/L), or S (K(i) = 14.3 nmol/L). In an in situ enzyme assay, SB 331750 inhibited osteoclast-associated cathepsin activity in tissue sections containing human osteoclasts (IC(50) approximately 60 nmol/L) and this translated into potent inhibition of human osteoclast-mediated bone resorption in vitro (IC(50) approximately 30 nmol/L). In vitro, SB 331750 partially, but dose-dependently, prevented the parathyroid hormone-induced hypercalcemia in an acute rat model of bone resorption. To evaluate the ability of SB 331750 to inhibit bone matrix degradation in vivo, it was administered for 4 weeks at 3, 10, or 30 mg/kg, intraperitoneally (i.p.), u.i.d. in the ovariectomized (ovx) rat. Both 10 and 30 mg/kg doses of compound prevented the ovx-induced elevation in urinary deoxypyridinoline and prevented the ovx-induced increase in percent eroded perimeter. Histological evaluation of the bones from compound-treated animals indicated that SB 331750 retarded bone matrix degradation in vivo at all three doses. The inhibition of bone resorption at the 10 and 30 mg/kg doses resulted in prevention of the ovx-induced reduction in percent trabecular area, trabecular number, and increase in trabecular spacing. These effects on bone resorption were also reflected in inhibition of the ovx-induced loss in trabecular bone volume as assessed using microcomputerized tomography (microCT; approximately 60% at 30 mg/kg). Together, these data indicate that the cathepsin K inhibitor, SB 331750, prevented bone resorption in vivo and this inhibition resulted in prevention of ovariectomy-induced loss in trabecular structure.

Functional and structural changes of the epidermal barrier induced by various types of insults in hairless mice

Acute barrier disruption, regardless of the method of induction, depletes the stratum corneum intercellular lipids and this stimulates a series of lipid/ DNA synthesis activities which lead to barrier recovery. After barrier disruption by tape stripping, occlusion with a water vapor-impermeable membrane inhibits barrier repair. In this study, we investigated the changes in the murine epidermis after barrier perturbation by tape stripping and three different types of surfactants (Emalex NP-12, ENP-12; sodium dodecyl sulfate, SDS; benzalkonium chloride, BKC). To examine the effect of an artificial barrier, we covered the animals with a water vapor-impermeable membrane for 3 days following barrier disruption and then exposed them to the air for 2 days. The histological findings after occlusion or air exposure were similar. However, after air exposure for 2 days, the thickness of the epidermis including the stratum corneum and the stratum granulosum layers decreased to about half that of the epidermis after occlusion. Ultrastructural examination revealed obvious distortion of the lamellar bilayers within the stratum corneum interstices immediately after barrier disruption. After 3 days of occlusion, extensive disorganization was evident in the intercellular domain of the stratum corneum, whereas 2 days after removal of the occlusion, the normal basic unit structure of the lamellar bilayers had partially reappeared. Our findings provide evidence that the kinetic pattern of barrier repair and the morphological changes are similar after occlusion following barrier disruption regardless of the mechanism of disruption.

Azepanone-based inhibitors of human and rat cathepsin K

The synthesis, in vitro activities, and pharmacokinetics of a series of azepanone-based inhibitors of the cysteine protease cathepsin K (EC 3.4.22.38) are described. These compounds show improved configurational stability of the C-4 diastereomeric center relative to the previously published five- and six-membered ring ketone-based inhibitor series. Studies in this series have led to the identification of 20, a potent, selective inhibitor of human cathepsin K (K(i) = 0.16 nM) as well as 24, a potent inhibitor of both human (K(i) = 0.0048 nM) and rat (K(i,app) = 4.8 nM) cathepsin K. Small-molecule X-ray crystallographic analysis of 20 established the C-4 S stereochemistry as being critical for potent inhibition and that unbound 20 adopted the expected equatorial conformation for the C-4 substituent. Molecular modeling studies predicted the higher energy axial orientation at C-4 of 20 when bound within the active site of cathepsin K, a feature subsequently confirmed by X-ray crystallography. Pharmacokinetic studies in the rat show 20 to be 42% orally bioavailable. Comparison of the transport of the cyclic and acyclic analogues through CaCo-2 cells suggests that oral bioavailability of the acyclic derivatives is limited by a P-glycoprotein-mediated efflux mechanism. It is concluded that the introduction of a conformational constraint has served the dual purpose of increasing inhibitor potency by locking in a bioactive conformation as well as locking out available conformations which may serve as substrates for enzyme systems that limit oral bioavailability.

Potent and selective cathepsin L inhibitors do not inhibit human osteoclast resorption in vitro

Cathepsins K and L are related cysteine proteases that have been proposed to play important roles in osteoclast-mediated bone resorption. To further examine the putative role of cathepsin L in bone resorption, we have evaluated selective and potent inhibitors of human cathepsin L and cathepsin K in an in vitro assay of human osteoclastic resorption and an in situ assay of osteoclast cathepsin activity. The potent selective cathepsin L inhibitors (K(i) = 0.0099, 0.034, and 0.27 nm) were inactive in both the in situ cytochemical assay (IC(50) > 1 micrometer) and the osteoclast-mediated bone resorption assay (IC(50) > 300 nm). Conversely, the cathepsin K selective inhibitor was potently active in both the cytochemical (IC(50) = 63 nm) and resorption (IC(50) = 71 nm) assays. A recently reported dipeptide aldehyde with activity against cathepsins L (K(i) = 0.052 nm) and K (K(i) = 1.57 nm) was also active in both assays (IC(50) = 110 and 115 nm, respectively) These data confirm that cathepsin K and not cathepsin L is the major protease responsible for human osteoclastic bone resorption.

The effects of famciclovir and epidural block in the treatment of herpes zoster

In our previous study, we concluded that an epidural blockade combined with intravenous acyclovir is very effective in treating the acute pain in herpes zoster and postherpetic neuralgia. We evaluated the efficacy of oral famciclovir and epidural blockade on the pain of herpes zoster, compared to acyclovir administered intravenously and epidural blockade. For this purpose, we examined a new group treated with famciclovir and epidural blockade to compare with the group treated with acyclovir and epidural blockade in our previously study. The changes in the intensity of pain, the number of days required for relief of pain, and the total duration of pain were checked. We compared the days required for relief of pain (DRP) and the total duration of pain (TDP) of this group with those of the previous studied group treated with acyclovir and epidural blockade. DRP was significantly less, but TDP was similar. DRP and TDP were significantly lower, if the patients were treated within 7 days of symptom onset. The patients had a shorter DRP regardless of pain type than the previously studied group treated with acycolvir and epidural blockade. For the severe and moderate pain grades, there was a shorter DRP from 100 to 10. TDP was not significantly different for the groups regardless of pain type or grade. We believe that famciclovir and epidural blockade are very effective in treating the pain of herpes zoster, with a view to shortening the period of acute pain, providing similar effects on the prevention of postherpetic neuralgia, and being convenient to administer, compared to intravenous acyclovir and epidural blockade in our previous study.

Human osteoclast cathepsin K is processed intracellularly prior to attachment and bone resorption

Cathepsin K is a member of the papain superfamily of cysteine proteases and has been proposed to play a pivotal role in osteoclast-mediated bone resorption. We have developed a sensitive cytochemical assay to localize and quantify osteoclast cathepsin K activity in sections of osteoclastoma and human bone. In tissue sections, osteoclasts that are distant from bone express high levels of cathepsin K messenger RNA (mRNA) and protein. However, the majority of the cathepsin K in these cells is in an inactive zymogen form, as assessed using both the cytochemical assay and specific immunostaining. In contrast, osteoclasts that are closer to bone contain high levels of immunoreactive mature cathepsin K that codistributes with enzyme activity in a polarized fashion toward the bone surface. Polarization of active enzyme was clearly evident in osteoclasts in the vicinity of bone. The osteoclasts apposed to the bone surface were almost exclusively expressing the mature form of cathepsin K. These cells showed intense enzyme activity, which was polarized at the ruffled border. These results suggest that the in vivo activation of cathepsin K occurs intracellularly, before secretion into the resorption lacunae and the onset of bone resorption. The processing of procathepsin K to mature cathepsin K occurs as the osteoclast approaches bone, suggesting that local factors may regulate this process.

Basis of occlusive therapy in psoriasis: correcting defects in permeability barrier and calcium gradient

BACKGROUND

Although occlusive dressings have great potential in the management of psoriasis vulgaris, the therapeutic mechanism is not completely understood. Occlusion artificially restores and corrects the defective barrier in psoriasis plaques. Additionally, occlusion is know to normalize the epidermal calcium gradients in hyperproliferative murine skin models.

METHODS

To investigate the basis of the therapeutic effect of occlusion on psoriatic plaques, we investigated the ultrastructural morphology of intercorneocyte lipid layers, lamellar bodies, and calcium gradient in chronic plaque-type psoriasis after occlusion with a water vapor-impermeable membrane. The specimens were processed for electron microscopy using: (i) ruthenium tetroxide postfixation; and (ii) ion-capture cytochemistry for calcium localization.

RESULTS

Occlusion for 7 days resulted in a nearly mature pattern of intercellular multilamellar structures, re-establishment of the near-normal epidermal calcium gradient, and disappearance of calcium precipitates from the stratum corneum interstices.

CONCLUSIONS

The normalization of the permeability barrier and epidermal calcium gradient may play important roles in the therapeutic effects of occlusive dressings in chronic plaque-type psoriasis.

Biosynthesis and processing of cathepsin K in cultured human osteoclasts

Cathepsin K (cat K) is the major cysteine protease expressed in osteoclasts and is thought to play a key role in matrix degradation during bone resorption. However, little is known regarding the synthesis, activation, or turnover of the endogenous enzyme in osteoclasts. In this study, we show that mature cat K protein and enzyme activity are localized within osteoclasts. Pulse-chase experiments revealed that, following the synthesis of pro cat K, intracellular conversion to the mature enzyme occurred in a time-dependent manner. Subsequently, the level of mature enzyme decreased. Little or no cat K was observed in the culture media at any timepoint. Pretreatment of osteoclasts with either chloroquine or monensin resulted in complete inhibition of the processing of newly synthesized cat K. In addition, pro cat K demonstrated susceptibility to treatment with N-glycosidase F, suggesting the presence of high-mannose-containing oligosaccharides. Treatment of osteoclasts with the PI3-kinase inhibitor, Wortmannin (WT), not only prevented the intracellular processing of cat K but also resulted in the secretion of proenzyme into the culture media. Taken together, these results suggest that the biosynthesis, processing, and turnover of cat K in human osteoclasts is constitutive and occurs in a manner similar to that of other known cysteine proteases. Furthermore, cat K is not secreted as a proenzyme, but is processed intracellularly, presumably in lysosomal compartments prior to the release of active enzyme into the resorption lacunae.

Antagonism of the osteoclast vitronectin receptor with an orally active nonpeptide inhibitor prevents cancellous bone loss in the ovariectomized rat

An orally active, nonpeptide Arg-Gly-Asp (RGD) mimetic alpha(v)beta3 antagonist, (S)-3-Oxo-8-[2-[6-(methylamino)-pyridin-2-yl]-1-ethoxy]-2-(2,2,2-trifluoroethyl)-2,3,4,5-tetrahydro-1H-2-benzazepine-4-acetic acid (compound 1), has been generated, which prevented net bone loss and inhibited cancellous bone turnover in vivo. The compound binds alpha(v)beta3 and the closely related integrin alpha(v)beta5 with low nanomolar affinity but binds only weakly to the related integrins alpha(IIb)beta3, and alpha5beta1. Compound 1 inhibited alpha(v)beta3-mediated cell adhesion with an IC50 = 3 nM. More importantly, the compound inhibited human osteoclast-mediated bone resorption in vitro with an IC50 = 11 nM. In vivo, compound 1 inhibited bone resorption in a dose-dependent fashion, in the acute thyroparathyroidectomized (TPTX) rat model of bone resorption with a circulating EC50 approximately 20 microM. When dosed orally at 30 mg/kg twice a day (b.i.d.) in the chronic ovariectomy (OVX)-induced rat model of osteopenia, compound 1 also prevented bone loss. At doses ranging from 3 to 30 mg/kg b.i.d., compound 1 partially prevented the OVX-induced increase in urinary deoxypyridinoline. In addition, the compound prevented the OVX-induced reduction in cancellous bone volume (BV), trabecular number (Tb.N), and trabecular thickness (Tb.Th), as assessed by quantitative microcomputerized tomography (microCT) and static histomorphometry. Furthermore, both the 10-mg/kg and 30-mg/kg doses of compound prevented the OVX-induced increase in bone turnover, as measured by percent osteoid perimeter (%O.Pm). Together, these data indicate that the alpha(v)beta3 antagonist compound 1 inhibits OVX-induced bone loss. Mechanistically, compound 1 prevents bone loss in vivo by inhibiting osteoclast-mediated bone resorption, ultimately preventing cancellous bone turnover.

Chitinous materials inhibit nitric oxide production by activated RAW 264.7 macrophages

Chitinous materials have been studied in wound healing and artificial skin substitutes for many years. Nitric oxide (NO) has been shown to contribute to cytotoxicity in cell proliferation during inflammation of wound healing. In this study, we examined the effect of chitin and its derivatives on NO production by activated RAW 264.7 macrophages. Chitin and chitosan showed a significantly inhibitory effect on NO production by the activated macrophages. Hexa-N-acetylchitohexaose and penta-N-acetylchitopentaose also inhibited NO production but with less potency. However, N-acetylchitotetraose, -triose, -biose, and monomer of chitin, N-acetylglucosamine and glucosamine had little effect on NO production by the activated cells. These results suggest that the promotive effect of chitinous material on wound healing be related, at least partly, to inhibit NO production by the activated macrophages.

Structural and functional effects of oleic acid and iontophoresis on hairless mouse stratum corneum

The aim of this study was to assess the effects of chemical and electrical modes of percutaneous penetration enhancement on the intercellular lipid lamellae of the stratum corneum. Hairless mice were treated with either oleic acid/propylene glycol and iontophoresis separately or together. Permeability barrier function was evaluated by measuring transepidermal water loss and correlated with the structure of stratum corneum intercellular lamellae, as evaluated by electron microscopy, using ruthenium tetroxide postfixation. Transepidermal water loss levels did not change following 1 h iontophoresis alone. In contrast, topical applications of 0.3 M oleic acid in propylene glycol for 1 h increased transepidermal water loss significantly. Moreover, the combined use of iontophoresis plus 0.3 M oleic acid for 1 h further increased transepidermal water loss at equivalent time points. Ultrastructural observations demonstrated both marked disorganization of the intercellular lipid lamellae, as well as the presence of distended lacunae within the stratum corneum in oleic acid/propylene glycol plus or minus iontophoresis-treated stratum corneum. This study provides direct evidence that the oleic acid/propylene glycol system can disrupt the stratum corneum lipid lamellar structures, and that coapplications of oleic acid with iontophoresis further enhance the effects of oleic acid. The synergy between chemical and physical enhancement may afford a new approach to promote transdermal drug delivery.

Pincer nail deformity and pseudo-Kaposi's sarcoma: complications of an artificial arteriovenous fistula for haemodialysis

Pseudo-Kaposi's sarcoma which develops due to arteriovenous fistulae for haemodialysis is relatively well known. In contrast, nail changes associated with pseudo-Kaposi's sarcoma or venous hypertension are rare. We report a novel case of pincer nail deformity associated with pseudo-Kaposi's sarcoma and venous hypertension, complications of an arteriovenous fistula for haemodialysis, and review eight similar cases reported in the literature. Most of the subjects presented with similar findings, having circulatory disturbance due to an arteriovenous fistula and/or increased venous pressure, and swelling, discoloration and papules/nodules of the skin distal to the shunt. Of the nine patients, three had overcurvature of the nails, in which the lateral edge of the nail pressed deeply into the lateral nail fold. Pincer nail deformity associated with pseudo-Kaposi's sarcoma after placement of an arteriovenous fistula may be relatively common and should be recognized as a specific sign of circulatory disturbance due to the arteriovenous fistula.

The pretreatment effect of chemical skin penetration enhancers in transdermal drug delivery using iontophoresis

The transdermal drug delivery (TDD) system has largely been divided into physical, biochemical and chemical methods. Recently, combinations of these methods were introduced for more effective delivery with less side effects. We performed this study to identify the effectiveness and mechanism of TDD using the physical method, 'iontophoresis', plus the chemical method, 'pretreatment with chemical enhancer'. The action sites of chemical enhancers in the stratum corneum (SC) were observed by electron microscope. We also studied whether this combined method synergistically impaired the skin barrier. To confirm the synergistic effect on skin penetration by this combined method, we measured the blood glucose level after insulin iontophoresis following a chemical enhancer pretreatment in rabbits. The results were that (1) dilatation of the intercellular lipid layers of the SC and lacunae was prominent in pretreatment with chemical enhancers inducing high transepidermal water loss (TEWL); (2) the skin barrier impairment, with repeated treatments showing an increased TEWL and also epidermal proliferation, was increased with the chemical enhancers that showed a high TEWL immediately after treatment; (3) the combination of chemical enhancer pretreatment and iontophoresis showed no synergistic impairment of the skin barrier, and (4) the chemical enhancer pretreatment with greater impairment of the skin barrier could increase the delivery of insulin by iontophoresis. The results showed that a combination of chemical enhancer pretreatment and iontophoresis could deliver drugs more effectively than iontophoresis alone. Our proposed theory is that iontophoretic drug delivery may be easier through the dilated intercellular spaces of the SC which have a lower electrical impedance following the chemical enhancer pretreatment. Because the effect and the side effects in the combination are decided by the chemical enhancer rather than iontophoresis, the development of proper chemical enhancers is important in future plans.

The effects of epidural blockade on the acute pain in herpes zoster

OBJECTIVE

To evaluate the relief of acute pain and possible preventive effects on postherpetic neuralgia through the use of an epidural blockade in the acute stage of herpes zoster.

DESIGN

Prospective, nonrandomized, comparative clinical trial.

SETTING

A dermatologic clinic in a university hospital.

PATIENTS

Sixty-five consecutive patients with pain due to acute herpes zoster were treated for a 7-day hospitalization period from July 1, 1996, through June 30, 1997.

INTERVENTION

The consecutive patients were divided into 2 groups. Group A consisted of 30 patients who were seen from July 1, 1996, through December 31, 1996, and who were treated with intravenous acyclovir (5 mg/kg) for 7 days. Group B consisted of 35 patients who were seen from January 1, 1997, through June 30, 1997, and who were treated with intravenous acyclovir (5 mg/kg) and an epidural blockade for 7 days. The changes in the intensity of pain and the total duration of pain in both groups were assessed for 12 to 18 months.

MAIN OUTCOME MEASURES

The number of days required for relief of pain and the total duration of pain.

RESULTS

The mean +/- SD number of days required for relief of pain, which was rated on a scale of 100 (worst pain) to 0 (no pain), was significantly fewer in group B than in group A: it took 2.6 +/- 1.1 days to go from 100 to 50 on the relief-of-pain scale in group B, but 3.8 +/- 1.1 days in group A (P = .03), and 12.5 +/- 6.4 days to go from 100 to 10 in group B, but 20.1 +/- 14.6 days in group A (P = .04). The duration of late residual pain was significantly shorter in group B (5.9 +/- 5.8 days) than in group A (11.9 +/- 7.5 days) (P = .03). The total duration of pain was also significantly shorter in group B (18.5 +/- 9.3 days) than in group A (31.6 +/- 17.6 days) (P = .04).

CONCLUSIONS

We believe that an epidural blockade combined with an antiviral agent is a very effective treatment modality for the pain of acute herpes zoster, and we recommend its use for the prevention of postherpetic neuralgia, with a view to shortening the total duration of pain, especially late residual pain.

Design and characterization of orally active Arg-Gly-Asp peptidomimetic vitronectin receptor antagonist SB 265123 for prevention of bone loss in osteoporosis

The Arg-Gly-Asp (RGD)-binding integrin alpha(V)beta(3) is highly expressed on osteoclasts and has been proposed to mediate cell-matrix adhesion required for osteoclast-mediated bone resorption. Antagonism of this receptor should prevent stable osteoclast adhesion and thereby inhibit bone resorption. We have generated an orally bioavailable, nonpeptide RGD mimetic alpha(v)beta(3) antagonist, SB 265123, which prevents bone loss in vivo when dosed by oral administration. SB 265123 binds alpha(v)beta(3) and the closely related integrin alpha(v)beta(5) with high affinity (K(i) = 3.5 and 1.3 nM, respectively), but binds only weakly to the related RGD-binding integrins alpha(IIb)beta(3) (K(i) >1 microM) and alpha(5)beta(1) (K(i) >1 microM). The compound inhibits alpha(v)beta(3)-mediated cell adhesion with an IC(50) = 60 nM and more importantly, inhibits human osteoclast-mediated bone resorption in vitro with an IC(50) = 48 nM. In vivo, SB 265123 completely blocks bone resorption in a thyroparathyroidectomized rat model of acute bone resorption when dosed at 2.5 mg/kg/h by continuous i.v. infusion. When dosed orally with 3 to 30 mg/kg b.i.d. , in the ovariectomy-induced rat model of osteoporosis, SB 265123 prevents bone resorption in a dose-dependent fashion. This is the first report of an orally active alpha(v)beta(3) antagonist that is effective at inhibiting bone resorption when dosed in a pharmaceutically acceptable fashion. Such a molecule may provide a novel therapeutic agent for the treatment of postmenopausal osteoporosis.

Characterization of the DNA binding and bending HMG domain of the yeast hypoxic repressor Rox1

The yeast Rox1 hypoxic transcriptional repressor protein binds to and bends a specific DNA sequence through an HMG domain located at the N-terminus. To better understand the structure of Rox1 and how it interacts with DNA, 38 missense mutations in the HMG domain were isolated through a combination of random and site-directed mutageneses, the latter directed to two Ile residues that play an important role in DNA recognition and bending by HMG domains. The mutants were characterized in terms of their ability to repress the hypoxic gene ANB1 and the auto-repressed ROX1 gene in vivo. The mutant HMG domains were fused to maltose binding protein and expressed in and purified from Escherichia coli and their relative affinities for DNA and ability to bend DNA were determined. A model of the structure of the Rox1 HMG domain was derived using sequence similarities between Rox1 and the human protein SRY, the structure of which has been determined. The results of the mutational analysis are interpreted in terms of the model structure of Rox1.

Development and characterization of a human in vitro resorption assay: demonstration of utility using novel antiresorptive agents

A human in vitro resorption assay has been developed using osteoclastoma-derived osteoclasts and used to evaluate novel antiresorptive agents including antagonists of the alphavbeta3 integrin, and inhibitors of cathepsin K and the osteoclast ATPase. The potency of novel compounds in the in vitro resorption assay correlates with functional assays for each class of inhibitor: the human alphavbeta3-mediated cell adhesion assay for the vitronectin receptor antagonists (r2 = 0.82), the chick osteoclast vacuolar ATPase enzyme assay for the H+-ATPase inhibitors (r2 = 0.77) and the recombinant human cathepsin K enzyme assay for the cathepsin K inhibitors (r2 = 0.80). Cell suspensions, rich in osteoclasts, are prepared by collagenase digestion of the tumor tissue. These cells can be stored long-term in liquid nitrogen and upon thawing maintain their bone-resorbing phenotype. The cryopreserved cells can be cultured on bovine cortical bone for 24-48 h and resorption can be measured by either confocal microscopy or biochemical assays. The resorptive activity of osteoclasts derived from a number of tumors can be inhibited reproducibly using a number of mechanistically unique antiresorptive compounds. In addition, the measurement of resorption pits by laser confocal microscopy correlates with the release of type I collagen C-telopeptides or N-telopeptides, as measured by enzyme-linked immunosorbent assay. Resorption can be measured reproducibly using a 48-h incubation of osteoclasts on bone slices, or a 24-h incubation with bone particles. This in vitro human osteoclast resorption assay provides a robust system for the evaluation of inhibitors of osteoclastic function that may be developed for the treatment of metabolic bone diseases such as osteoporosis.

The changes of epidermal calcium gradient and transitional cells after prolonged occlusion following tape stripping in the murine epidermis

Disruption of the epidermal permeability barrier causes an immediate loss of the calcium gradient, and barrier recovery is parallel with the restoration of the calcium gradient in the epidermis. Artificial restoration of the barrier function by occlusion with a water vapor-impermeable membrane abrogate the expected increase in lipid synthesis and retard the barrier recovery, as well as block the normalization of the epidermal calcium gradient. To clarify the long-term effects of occlusion after acute barrier perturbation, we studied the calcium distribution and epidermal keratinocytes response after occlusion with a water vapor-impermeable membrane immediately following tape stripping in the murine epidermis. Acute barrier disruption caused an immediate depletion of most calcium ions in the upper epidermis, obliterating the normal calcium gradient. When the skin barrier function was artificially corrected by occlusion, the return of calcium ions to the epidermis was blocked. After 2 h of air exposure or occlusion, the density of epidermal calcium precipitates remained negligible. The transitional cell layers appeared with occlusion, but not or negligibly with air exposure. By 6 h though, calcium precipitates could be seen, the density of the calcium precipitates with occlusion was more sparse than with air exposure. With the air exposure, the thickness of the stratum corneum had normalized and the calcium gradient nearly recovered to normal after 24 h. The longer the occlusion period, the greater was the increase of transitional cells. By 60 h of occlusion, the thickness of the stratum corneum had increased and the transitional cell layers had disappeared, in parallel with the calcium gradient which was almost normalized. These results show that prolonged occlusion of tape-stripped epidermis induced transitional cells and delayed the restoration of the epidermal calcium gradient, the stratum corneum was then restored, transitional cells having disappeared, in parallel with normalization of the epidermal calcium gradient.

Acne mechanica due to an orthopedic crutch

Acne mechanica describes local irritation due to the skin being pressured, occluded, rubbed, squeezed, stretched, or heated. Examples of various physical traumas that provoke lesions in acne patients are given. Users of orthopedic crutches are at particular risk for such conditions. A crutch is another extrinsic factor to be added to the list of causes of acne mechanica.

Orally bioavailable nonpeptide vitronectin receptor antagonists with efficacy in an osteoporosis model

A new series of potent nonpeptide vitronectin receptor antagonists, based on a novel carbocyclic Gly-Asp mimetic, has been discovered. A representative of this series, SB 265123 (4), has 100% oral bioavailability in rats, and is orally active in vivo in the ovariectomized rat model of osteoporosis.

Orally bioavailable nonpeptide vitronectin receptor antagonists containing 2-aminopyridine arginine mimetics

A peptide RGD analog containing a novel 2-aminopyridine arginine mimetic was discovered to have good affinity and selectivity for the vitronectin receptor. Incorporation of the 2-aminopyridine arginine mimetic into the 3-oxo-1,4-benzodiazepine-2-acetic acid integrin antagonist series led to novel and potent nonpeptide vitronectin receptor antagonists with promising levels of oral bioavailability.

Identification and cloning of a connective tissue growth factor-like cDNA from human osteoblasts encoding a novel regulator of osteoblast functions

We have identified and cloned a novel connective tissue growth factor-like (CTGF-L) cDNA from primary human osteoblast cells encoding a 250-amino acid single chain polypeptide. Murine CTGF-L cDNA, encoding a polypeptide of 251 amino acids, was obtained from a murine lung cDNA library. CTGF-L protein bears significant identity ( approximately 60%) to the CCN (CTGF, Cef10/Cyr61, Nov) family of proteins. CTGF-L is composed of three distinct domains, an insulin-like growth factor binding domain, a von Willebrand Factor type C motif, and a thrombospondin type I repeat. However, unlike CTGF, CTGF-L lacks the C-terminal domain implicated in dimerization and heparin binding. CTGF-L mRNA ( approximately 1.3 kilobases) is expressed in primary human osteoblasts, fibroblasts, ovary, testes, and heart, and a approximately 26-kDa protein is secreted from primary human osteoblasts and fibroblasts. In situ hybridization indicates high expression in osteoblasts forming bone, discrete alkaline phosphatase positive bone marrow cells, and chondrocytes. Specific binding of 125I-labeled insulin-like growth factors to CTGF-L was demonstrated by ligand Western blotting and cross-linking experiments. Recombinant human CTGF-L promotes the adhesion of osteoblast cells and inhibits the binding of fibrinogen to integrin receptors. In addition, recombinant human CTGF-L inhibits osteocalcin production in rat osteoblast-like Ros 17/2.8 cells. Taken together, these results suggest that CTGF-L may play an important role in modulating bone turnover.

Disseminated superficial actinic porokeratosis like drug eruption: a case report

We report a 54-year-old male patient who developed an unusual form of generalized drug eruption. He had pain and breathlessness on the left chest wall. He had history of taking several drugs at private clinics under a diagnosis of herpes zoster. Two weeks later he had a generalized skin eruption. Examination showed multiple variable sized, mild pruritic, erythematous macules and papules on the face and upper extremities. Skin lesions take the form of a clinically consistent with disseminated superficial actinic porokeratosis (DSAP). Methylprednisolone 16 mg, astemisole 10 mg, oxatomide 60 mg was prescribed. Topical corticosteroid cream was applied. Within two months, his eruption had cleared almost completely. The pathogenetic mechanisms of this case are unclear, but drug and UV light have been considered.

Nurse's cap alopecia

BACKGROUND

Traction alopecia associated with the nurse's cap is a relatively common form of occupational hair loss.

METHODS

We examined 199 healthy South Korean nurses to assess the clinical and pathologic characteristics of traction alopecia caused by prolonged traction exerted at the point of attachment of the nurse's cap.

RESULTS

Seven nurses (3.5% of 199) had hair loss at the pin site used to secure the nurse's cap. The lesions were exclusively localized on the parieto-occipital scalp. Histopathologic findings revealed characteristic cicatricial changes which showed a marked decrease in the number of hair follicles without inflammation.

CONCLUSIONS

Nurse's cap alopecia is not an uncommon occupational alopecia, and appears to be a distinct clinical entity which should be distinguished from other forms of patchy alopecia.

Conformational preferences in a benzodiazepine series of potent nonpeptide fibrinogen receptor antagonists

Previously, we reported the direct design of highly potent nonpeptide 3-oxo-1,4-benzodiazepine fibrinogen receptor antagonists from a constrained, RGD-containing cyclic semipeptide. The critical features incorporated into the design of these nonpeptides were the exocyclic amide at the 8-position which overlaid the Arg carbonyl, the phenyl ring which maintained an extended Gly conformation, and the diazepine ring which mimicked the gamma-turn at Asp. In this paper, we investigate conformational preferences of the 8-substituted benzodiazepine analogues by examining structural modifications to both the exocyclic amide and the seven-membered diazepine ring and by studying the conformation of the benzodiazepine ring using molecular modeling, X-ray crystallography, and NMR. We found that the directionality of the amide at the 8-position had little effect on activity and the (E)-olefin analogue retained significant potency, indicating that the trans orientation of the amide, and not the carbonyl or NH groups, made the largest contribution to the observed activity. For the diazepine ring, with the exception of the closely analogous 3-oxo-2-benzazepine ring system described previously, all of the modifications led to a significant reduction in activity compared to the potent 3-oxo-1, 4-benzodiazepine parent ring system, implicating this particular type of ring system as a desirable structural feature for high potency. Energy minimizations of a number of the modified analogues revealed that none could adopt the same low-energy conformation as the one shared by the active (S)-isomer of the 3-oxo-1, 4-benzodiazepines and 3-oxo-2-benzazepines. The overall data suggest that the features contributing to the observed high potency in this series are the orientation of the 3-4 amide and the conformational constraint imposed by the seven-membered ring, both of which position the key acidic and basic groups in the proper spatial relationship.

The anatomy of a hypoxic operator in Saccharomyces cerevisiae

Aerobic repression of the hypoxic genes of Saccharomyces cerevisiae is mediated by the DNA-binding protein Rox1 and the Tup1/Ssn6 general repression complex. To determine the DNA sequence requirements for repression, we carried out a mutational analysis of the consensus Rox1-binding site and an analysis of the arrangement of the Rox1 sites into operators in the hypoxic ANB1 gene. We found that single base pair substitutions in the consensus sequence resulted in lower affinities for Rox1, and the decreased affinity of Rox1 for mutant sites correlated with the ability of these sites to repress expression of the hypoxic ANB1 gene. In addition, there was a general but not complete correlation between the strength of repression of a given hypoxic gene and the compliance of the Rox1 sites in that gene to the consensus sequence. An analysis of the ANB1 operators revealed that the two Rox1 sites within an operator acted synergistically in vivo, but that Rox1 did not bind cooperatively in vitro, suggesting the presence of a higher order repression complex in the cell. In addition, the spacing or helical phasing of the Rox1 sites was not important in repression. The differential repression by the two operators of the ANB1 gene was found to be due partly to the location of the operators and partly to the sequences between the two Rox1-binding sites in each. Finally, while Rox1 repression requires the Tup1/Ssn6 general repression complex and this complex has been proposed to require the aminoterminal regions of histones H3 and H4 for full repression of a number of genes, we found that these regions were dispensable for ANB1 repression and the repression of two other hypoxic genes.