A nomogram for predicting hospital mortality of critical ill patients with sepsis and cancer: a retrospective cohort study based on MIMIC-IV and eICU-CRD

OBJECTIVE

Sepsis remains a high cause of death, particularly in immunocompromised patients with cancer. The study was to develop a model to predict hospital mortality of septic patients with cancer in intensive care unit (ICU).

DESIGN

Retrospective observational study.

SETTING

Medical Information Mart for Intensive Care IV (MIMIC IV) and eICU Collaborative Research Database (eICU-CRD).

PARTICIPANTS

A total of 3796 patients in MIMIC IV and 549 patients in eICU-CRD were included.

PRIMARY OUTCOME MEASURES

The model was developed based on MIMIC IV. The internal validation and external validation were based on MIMIC IV and eICU-CRD, respectively. Candidate factors were processed with the least absolute shrinkage and selection operator regression and cross-validation. Hospital mortality was predicted by the multivariable logistical regression and visualised by the nomogram. The model was assessed by the area under the curve (AUC), calibration curve and decision curve analysis curve.

RESULTS

The model exhibited favourable discrimination (AUC: 0.726 (95% CI: 0.709 to 0.744) and 0.756 (95% CI: 0.712 to 0.801)) in the internal and external validation sets, respectively, and better calibration capacity than Acute Physiology and Chronic Health Evaluation IV in external validation.

CONCLUSIONS

Despite that the predicted model was based on a retrospective study, it may also be helpful to predict the hospital morality of patients with solid cancer and sepsis.

Short- and medium-term survival of critically ill patients with solid cancer admitted to the intensive care unit

BACKGROUND

A great increase in the number of patients needs critical care to the intensive care unit (ICU) due to improvements in oncology. The aim of the study was to explore risk factors affecting survival of critically ill patients with solid cancers in ICU.

METHODS

The study retrospectively reviewed patients between 2001 and 2012, which were collected by Medical Information Mart for Intensive Care III (MIMIC-III) from the Beth Israel Deaconess Medical Center in Boston, MA, USA.

RESULTS

A total of 38,508 adult patients, who were admitted to ICUs and 8,308 (21.6%) were diagnosed as an underlying malignancy; 1,671 and 3,165 adult patients with sold cancer were admitted to surgical ICU (SICU) and medical ICU (MICU), respectively. Patients in SICU had a higher survival rate at the point of 28-, 90-day, and 1-, 3-year than patients in MICU (P<0.001 for all). Multivariate analysis demonstrated that age ≥70, emergency admission, the presence of metastases, Oxford Acute Severity of Illness Score (OASIS) ≥30 and sepsis were independent risk factors affecting 28-day survival in SICU. In MICU, emergency admission, metastatic disease, Sequential Organ Failure Assessment (SOFA) ≥3, Simplified Acute Physiology Score II (SAPS II) ≥39, Acute Physiology Score III (APS III) ≥40, Oxford Acute Severity of Illness Score (OASIS) ≥30, Elixhauser comorbidity index ≥9 and sepsis were independent risk factors for 28-day survival rate. The area under curve (AUC) of the OASIS for predicting ICU mortality was 0.824 [95% confidence interval (CI): 0.805-0.842], which was obviously higher than other scores in SICU. The AUC of the SAPS II for predicting ICU mortality was 0.820 (95% CI: 0.806-0.833), which was slightly higher than other scores in MICU.

CONCLUSIONS

Patients with cancer in SICU have longer survive time than patients with cancer in MICU. The prediction of prognosis of critically ill cancer patients can guide treatment and optimize medical resources.

The effect of the underlying malignancy on short- and medium-term survival of critically ill patients admitted to the intensive care unit: a retrospective analysis based on propensity score matching

Background

Advances in oncology led to a substantial increase in the number of patients requiring admission to the ICU. It is significant to confirm which cancer critical patients can benefit from the ICU care like noncancer patients.

Methods

An observational retrospective cohort study using intensive care unit (ICU) admissions of Medical Information Mart for Intensive Care III from the Beth Israel Deaconess Medical Center in Boston, MA, USA between 2001 and 2012 was conducted. Propensity score matching was used to reduce the imbalance between two matched cohorts. ICU patients with cancer were compared with those without cancer in terms of patients’ characteristics and survival.

Results

There were 38,508 adult patients admitted to ICUs during the period. The median age was 65 years (IQR, 52–77) and 8308 (21.6%) had an underlying malignancy diagnosis. The noncancer group had a significant survive advantage at the point of 28-day, 90-day, 365-day and 1095-day after ICU admission compared with cancer group (P < 0.001 for all) after PSM. Subgroup analysis showed that the diagnosis of malignancy didn’t decrease 28-day and 90-day survive when patients’ age ≥ 65-year, patients in surgical intensive care unit or cardiac surgery recovery unit or traumatic surgical intensive care unit, elective admissions, patients with renal replacement therapy or vasopressor support (P > 0.05 for all).

Conclusions

Malignancy is a common diagnosis among ICU patients. Patients without cancer have a survive advantage compared with patients with cancer in the short- and medium-term. However, in selected groups, cancer critical patients can benefit from the ICU care service like noncancer patients in the short-term.

Impaired intestinal barrier function in type 2 diabetic patients measured by serum LPS, Zonulin, and IFABP

INTRODUCTION

The epithelial tight junctions of intestine were impaired in murine model of type 2 diabetes mellitus (T2DM). The aim of this work was to investigate the alteration of intestinal barrier in T2DM patients.

METHODS

90 patients with T2DM and 28 healthy controls were recruited. Serum lipopolysaccharide (LPS), Zonulin, and intestinal fatty acid binding protein (IFABP) were measured by ELISA, based on which a derived permeability risk score (PRS) was calculated. Subgroup analyses were conducted based on the glycemic control (HbA1c < 7%, or HbA1c ≥ 7%), the amount of chronic diabetic complications, and the use of aspirin at the time.

RESULTS

Serum LPS, Zonulin, and IFABP, and PRS of T2DM group were significantly higher than those of the control group (p < 0.05 for all). Serum LPS and PRS was higher in T2DM patients with poor glycemic control (both p < 0.05). Patients with more chronic complications of diabetes had higher serum LPS and IFABP, and PRS (all p < 0.05). No differences were found in these serum markers between T2DM patients being treated with aspirin or not.

CONCLUSIONS

Intestinal barrier function was impaired in T2DM patients. Poor glycemic control and more chronic complications of diabetes were associated with worse intestinal barrier function. Treatment with aspirin did not aggravate the impairment of intestinal barrier in T2DM patients.

A randomized controlled trial comparing the efficacy of tigecycline versus meropenem in the treatment of postoperative complicated intra-abdominal infections

BACKGROUND

The efficacy and safety of tigecycline in the treatment of complicated intra-abdominal infections (cIAIs) is potentially controversial. Here we conducted the non-inferiority study to assess the efficacy and safety of tigecycline versus meropenem in the treatment of postoperative cIAIs.

METHODS

Data of abdominal tumor surgery patients with postoperative cIAIs admitted to intensive care unit (ICU) between October 2017 and December 2019 were collected. A prospective, randomized controlled trial was conducted in which 56 eligible patients with cIAIs randomly received intravenous tigecycline or meropenem for 3 to 14 days. Patients and clinicians were not blinded to the group allocation.

RESULTS

The total of 56 patients were enrolled, which were divided into 2 groups, one group included 30 patients receiving meropenem and another group included 26 receiving tigecycline therapy. The 2 groups were similar at demographic and baseline clinical characteristics. Microorganisms were isolated from 46 of 56 patients (82.14%), with a total of 107 pathogens were cultured in two groups. The two groups had similar distribution of infecting microorganisms. The primary end point was the clinical response at the end-oftherapy (EOT) visit and upon discharge visit and comprehensive efficacy. The clinical success rates were 83.33%, 76.67% for meropenem versus 76.92%, 88.46% for tigecycline at the EOT visit and upon discharge visit (P>0.05), respectively. Comprehensive efficacy did not significantly differ between two groups either. There were no significant differences in 30-day and 60-day all-cause mortality between two groups (P>0.05). The univariable analysis identified that serum albumin at admission ICU, colorectal cancer on oncology type, postoperative abdominal bleeding were the risk factors for 60-day all-cause mortality. The multivariable analysis showed that postoperative abdominal bleeding were independent predictors of 60-day all-cause mortality. Gastrointestinal disorders and antibacterials-induced Fungal Infection were the most frequently reported adverse events (AEs). The incidence of AEs was similar between meropenem and tigecycline groups (P>0.05).

CONCLUSIONS

Taken together, the study demonstrated that tigecycline is as effective and safe as meropenem for postoperative cIAIs in abdominal tumors patients. Tigecycline is non-inferior to meropenem.

The 28-day survive for critically ill cancer patients undergoing continuous renal replacement with postoperative acute kidney injure: a retrospective study of 86 cases

Background

Advances in oncology led to a substantial increase in the number of patients requiring admission to the intensive care unit (ICU). It remains controversial to start continuous renal replacement therapy (CRRT) for acute kidney injure (AKI) in critically ill patients with cancer because of the poor outcome and high costs.

Methods

In this retrospective study, we collected data from patients with cancer with postoperative AKI-stage 3 [Kidney Disease: Improving Global Outcomes (KDIGO), 2012] undergoing CRRT in the ICU of Cancer Hospital, Chinese Academy of Medical Sciences from January 2010 to January 2019. Patients were followed up until the time of death or the point of 28-day after ICU admission. Univariate and multivariate analysis was performed to identify risk factors for 28-day survive.

Results

Of 8,030 cancer patients after surgical operation admitted by ICU, a total of 86 (1.1%) patients developed postoperative AKI: male/female: 62/24, median age 61 [27–82] years. The number of digestive tract/lung/other types of cancer was 59, 10 and 17, respectively. The median Simplified Acute Physiology Score III (SAPS III) was 65 [49–109] and the median Sequential Organ Failure Assessment (SOFA) score was 6 [1–19]. There were 35 deaths eventually and all the deaths occur within 28 days after ICU admission. Twenty-eight-day survive rate was 57.1%±5.8%. In multivariate cox regression analysis, two risk factors independently affected 28-day survive: SAPS III score ≥65 [hazard ratio (HR): 3.451 (1.272–9.365), P=0.015], the presence of shock at the start of CRRT [HR: 10.262 (2.210–47.660), P=0.003]. The cancer status (P=0.076), cancer types (P>0.05 for both) and neoadjuvant therapy associated with cancer (P=0.949) showed no effects on 28-day survive.

Conclusions

For cancer patients, postoperative AKI-stage 3 is a serious complication with a low 28-day survive rate. Patients with the presence shock at the start of CRRT or SAPS III ≥65 will have a poor 28-day survive. It should be emphasized that the cancer characteristics (status, types or treatment) don’t affect 28-day survive.

[Bivariate heritability estimation of resting heart rate and common chronic disease based on extended pedigrees]

OBJECTIVE

To estimate the univariate heritability of resting heart rate and common chronic disease such as hypertension, diabetes, and dyslipidemia based on extended pedigrees in Fujian Tulou area and to explore bivariate heritability to test for the genetic correlation between resting heart rate and other relative phenotypes.

METHODS

The study was conducted in Tulou area of Nanjing County, Fujian Province from August 2015 to December 2017. The participants were residents with Zhang surname and their relatives from Taxia Village, Qujiang Village, and Nanou Village or residents with Chen surname and their relatives from Caoban Village, Tumei Village, and Beiling Village. The baseline survey recruited 1 563 family members from 452 extended pedigrees. The pedigree reconstruction was based on the family information registration and the genealogy booklet. Univariate and bivariate heritability was estimated using variance component models for continuous variables, and susceptibility-threshold model for binary variables.

RESULTS

The pedigree reconstruction identified 1 seven-generation pedigree, 2 five-generation pedigrees, 23 four-generation pedigrees, 186 three-generation pedigrees, and 240 two-generation pedigrees. The mean age of the participants was 57.2 years and the males accounted for 39.4%. The prevalence of hypertension, diabetes, dyslipidemia in this population was 49.2%, 10.0%, and 45.2%, respectively. The univariate heritability estimation of resting heart rate, hypertension, and dyslipidemia was 0.263 (95%CI: 0.120－0.407), 0.404 (95%CI: 0.135－0.673), and 0.799 (95%CI: 0.590－1), respectively. The heritability of systolic blood pressure, diastolic blood pressure, fasting glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol was 0.379, 0.306, 0.393, 0.452, 0.568, 0.852, and 0.387, respectively. In bivariate analysis, there were phenotypic correlations between resting heart rate with hypertension, diabetes, diastolic blood pressure, fasting glucose, and triglyceride. After taking resting heart rate into account, there were strong genetic correlations between resting heart rate with fasting glucose (genetic correlation 0.485, 95%CI: 0.120－1, P<0.05) and diabetes (genetic correlation 0.795, 95%CI: 0.181－0.788, P<0.05).

CONCLUSION

Resting heart rate was a heritable trait and correlated with several common chronic diseases and related traits. There was strong genetic correlation between resting heart rate with fasting glucose and diabetes, suggesting that they may share common genetic risk factors.

Obesity-associated secondary hypogonadism in young and middle-aged men in Guangzhou: A single-centre cross-sectional study

AIM

Male obesity-associated secondary hypogonadism (MOSH) is becoming a public health issue. We aimed to know MOSH among young and middle-aged men in our hospital, to analyse their sex hormones and other index, and to determine leptin as a risk factor for MOSH.

METHODS

In total, 258 men (ages ranging from 20 to 60, mean 38 ± 15) were enrolled in this study, and 242 of these men had their complete data, body mass index (BMI), waist circumference and sex hormones retrospectively investigated. The leptin and lipid levels were also evaluated, and comparisons were made between young (20-39 years old) and middle-aged (40-60 years old) men.

RESULTS

Among all the participants, 7 were thin, with a BMI < 18.5 kg/m² , 95 had a normal BMI (18.5 ≤ BMI < 23.9 kg/m² ), 87 (35.9%) were overweight (24 ≤ BMI ≤ 27.9 kg/m² ) and 53 (21.9%) were obese (BMI ≥ 28 kg/m² ), 173 (71.5%) had a waist sized ≥ 85 cm. Among the 242 men, 104 (43%) had hypogonadism (TT ≤ 331.412 ng/dL). Compared with the men of normal weight, the level of testosterone of the obese men decreased (P = .006), while the level of serum lipids (including total cholesterol, TG and low-density lipoprotein cholesterol, P < .05) was elevated, higher UA, FSH and leptin were also present in the obese men. There were 83 (34.2%) men with MOSH. Compared with middle-aged men with MOSH, the FSH in young men was significantly reduced (P < .05); no significant increase in estradiol was observed in the MOSH group. The leptin levels in the MOSH group were significantly higher than those in the hypogonadism only group (P < .001).

CONCLUSION

Obesity increases the prevalence of hypogonadism. The decrease in testosterone levels in young men maybe due to inhibition of the hypothalamic pituitary gonadal axis. Leptin is an independent risk factor for MOSH.

[Fujian Tulou Family Cohort Study: study design and characteristics of participants and pedigrees in baseline investigation]

Objective: To describe the study design, the characteristics of participants as well as the pedigrees included in the baseline survey of Fujian Tulou Family Cohort Study. Methods: Fujian Tulou Family Cohort Study was a prospective open cohort study with a biological sample bank. A baseline survey was conducted in Tulou areas of Nanjing county in Fujian province from 2015 to 2018, including questionnaire survey, physical and biochemical indicators examinations, and blood sample collection in adults aged ≥18 years. In addition, family relationship of the participants was also recorded. The pedigree information of the juveniles under 18 years old were also collected. Results: The baseline survey included 2 727 individuals in two clans, of whom 2 373 (87.0%) were adults, and 2 126 participants completed questionnaires, physical examinations and biochemical tests. The average age of the 2 126 participants was (57.9±13.3) years, with 39.4% being males. The current smoking rates in male and female participants were 41.2% and 2.1%, respectively. The corresponding rates of current alcohol consumption were 19.0% and 2.6%. For common chronic diseases, the prevalence rates were 51.3% for hypertension, 9.7% for diabetes and 26.7% for hyperlipemia according to the self-reported disease diagnoses, health examination results and biochemical examination results in class Ⅱ or Ⅲ hospitals. Based on the family relationship information and genealogical data, 710 pedigrees were finally identified, consisting of 5 087 family members. The numbers of five, four, three, and two generations pedigrees were 3, 88, 238 and 381, respectively. The pairs of the first to the fifth degree relatives were 12 039, 2 662, 1 511, 202 and 31, respectively. Conclusion: The establishment of Fujian Tulou Family Cohort provides valuable resources for exploring the genetic risk factors, environmental risk factors and gene-environment interactions contributing to the risk of common chronic diseases.

Dissipation and residue of clothianidin in granules and pesticide fertilizers used in cabbage and soil under field conditions

The single application of 0.5 % clothianidin granules, a novel formulation, was used to control pests in vegetables under a high dose. In this article, residues of clothianidin in cabbage and soil samples under field conditions from Guangzhou, Nanning, and Qianjiang were determined by HPLC. The terminal residues of clothianidin in cabbage were less than the limit of detection (<LOD) at pre-harvest intervals of 30 days, and these values were lower than the maximum residue limit of 0.2 mg kg^-1 in cabbage set by the Codex Alimentarius Commission. To test on the influence of the pesticide fertilizers' effect on clothianidin residual, clothianidin granules and fertilizers of chicken manure, urea, and organic fertilizer were mixed into different pesticide fertilizers through their normal field using dosage and evaluate residual influence of clothianidin in different formula. After analysis of variance of the effect factors, the effect of different pesticide types on half-life was not significant, but the effect of sample types was significant. Clothianidin granules and pesticide fertilizers could be safely applied in cabbage under a single high-dose administration.

Preventable readmission to intensive care unit in critically ill cancer patients

BACKGROUND

Readmission to intensive care unit (ICU) after discharge to ward has been reported to be associated with increased hospital mortality and longer length of stay (LOS). The objective of this study was to investigate whether ICU readmission are preventable in critically ill cancer patients.

METHODS

Data of patients who readmitted to intensive care unit (ICU) at National Cancer Center/Cancer Hospital of Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC) between January 2013 and November 2016 were retrospectively collected and reviewed.

RESULTS

A total of 39 patients were included in the final analysis, and the overall readmission rate between 2013 and 2016 was 1.32% (39/2,961). Of 39 patients, 32 (82.1%) patients were judged as unpreventable and 7 (17.9%) patients were preventable. There were no significant differences in duration of mechanical ventilation, ICU LOS, hospital LOS, ICU mortality and in-hospital mortality between patients who were unpreventable and preventable. For 24 early readmission patients, 7 (29.2%) patients were preventable and 17 (70.8%) patients were unpreventable. Patients who were late readmission were all unpreventable. There was a trend that patients who were preventable had longer 1-year survival compared with patients who were unpreventable (100% vs. 66.8%, log rank=1.668, P=0.196).

CONCLUSION

Most readmission patients were unpreventable, and all preventable readmissions occurred in early period after discharge to ward. There were no significant differences in short term outcomes and 1-year survival in critically ill cancer patients whose readmissions were preventable or not.

[The relationship between nutritional status and oxidative stress markers, pulmonary function in patients with stable chronic obstructive pulmonary disease]

Objective: To investigate the association between the nutritional status of patients with chronic obstructive pulmonary disease (COPD) and the levels of serum oxidative stress markers protein carbonyls (PC), malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG), total antioxidant capacity (TAC) and pulmonary function. Methods: 200 patients with stable COPD (the COPD group) and 100 healthy individuals (the control group) who visited during June 2014 and August 2014 were enrolled in our study. The levels of PC, MDA, 8-OHdG and TAC in serum were detected. Pulmonary function was tested. Nutritional status was assessed by mini nutritional assessment (MNA) that classified the nutrition class. Results: The levels of PC, MDA, and 8-OHdG in serum increased significantly in the COPD group [3.82 (1.79, 6.83) μg/L, 3.89(2.77, 5.40) μmol/L and 359.18(259.25, 587.85) ng/L, respectively], and the levels of TAC in serum decreased significantly in COPD group [11.35(4.81, 20.20)U/ml], as compared with the control group [2.29(1.08, 3.26) μg/L, 3.08(2.32, 4.03) μmol/L, 311.37(265.47, 374.08) ng/L and 18.81(15.21, 23.19) U/ml, respectively, all P<0.05]. All the nutrition assessment parameters were gradually decreased as nutritional status worsen (all P<0.05). In malnourished (risk) COPD subgroup, the levels of PC and TAC in serum increased significantly [6.10(3.02, 8.18) μg/L and 13.33(6.07, 23.96) U/ml, respectively] and the FEV(1)% and FEV(1)/FVC index decreased significantly [42.90(34.68, 71.23) and 46.96(38.96, 60.63), respectively] as compared the well-nourished COPD subgroup [3.25(1.61, 5.37) μg/L, 9.99(4.41, 16.77) U/ml, 69.10(45.95, 89.23) and 53.32(42.13, 63.15), all P<0.05]. Furthermore, we had found that the upper arm muscle circumference, calf circumference and BMI were positively correlated with MNA (r=0.498, 0.587, 0.781, P<0.001), negatively correlated with PC (r=-0.209, -0.195, -0.231, P<0.05) and positively correlated with FEV(1)% (r=0.223, 0.274, 0.350, P<0.05). The upper arm muscle circumference and BMI were positively correlated with FEV(1)/FVC (r=0.166, 0.224, P<0.05). In COPD group, the level of PC in serum and FEV(1)% were important factor in MNA score, and the impacts of FEV(1)% were greater than the level of PC(β=0.367, -0.304, P<0.001). Conclusion: The protein carbonylation and airflow limitation might be closely related to malnutrition.

Optimisation of high-quality total ribonucleic acid isolation from cartilaginous tissues for real-time polymerase chain reaction analysis

Objectives

Studies which consider the molecular mechanisms of degeneration and regeneration of cartilaginous tissues are seriously hampered by problematic ribonucleic acid (RNA) isolations due to low cell density and the dense, proteoglycan-rich extracellular matrix of cartilage. Proteoglycans tend to co-purify with RNA, they can absorb the full spectrum of UV light and they are potent inhibitors of polymerase chain reaction (PCR). Therefore, the objective of the present study is to compare and optimise different homogenisation methods and RNA isolation kits for an array of cartilaginous tissues.

Materials and Methods

Tissue samples such as the nucleus pulposus (NP), annulus fibrosus (AF), articular cartilage (AC) and meniscus, were collected from goats and homogenised by either the MagNA Lyser or Freezer Mill. RNA of duplicate samples was subsequently isolated by either TRIzol (benchmark), or the RNeasy Lipid Tissue, RNeasy Fibrous Tissue, or Aurum Total RNA Fatty and Fibrous Tissue kits. RNA yield, purity, and integrity were determined and gene expression levels of type II collagen and aggrecan were measured by real-time PCR.

Results

No differences between the two homogenisation methods were found. RNA isolation using the RNeasy Fibrous and Lipid kits resulted in the purest RNA (A260/A280 ratio), whereas TRIzol isolations resulted in RNA that is not as pure, and show a larger difference in gene expression of duplicate samples compared with both RNeasy kits. The Aurum kit showed low reproducibility.

Conclusion

For the extraction of high-quality RNA from cartilaginous structures, we suggest homogenisation of the samples by the MagNA Lyser. For AC, NP and AF we recommend the RNeasy Fibrous kit, whereas for the meniscus the RNeasy Lipid kit is advised.

Cite this article: M. Peeters, C. L. Huang, L. A. Vonk, Z. F. Lu, R. A. Bank, M. N. Helder, B. Zandieh Doulabi. Optimisation of high-quality total ribonucleic acid isolation from cartilaginous tissues for real-time polymerase chain reaction analysis. Bone Joint Res 2016;5:560–568. DOI: 10.1302/2046-3758.511.BJR-2016-0033.R3.

The value of esophagectomy surgical apgar score (eSAS) in predicting the risk of major morbidity after open esophagectomy

BACKGROUND

Recently, surgical apgar score (SAS) has been reported to be strongly associated with major morbidity after major abdominal surgery. The aim of this study was to assess the value of esophagectomy SAS (eSAS) in predicting the risk of major morbidity after open esophagectomy in a high volume cancer center.

METHODS

The data of all patients who admitted to intensive care unit (ICU) after open esophagectomy at Cancer Hospital of Chinese Academy of Medical Sciences & Peking Union Medical College from September 2008 through August 2010 was retrospectively collected and reviewed. Preoperative and perioperative variables were recorded and compared. The eSAS was calculated as the sum of the points of EBL, lowest MAP and lowest HR for each patient. Patients were divided into high-risk (below the cutoff) and low-risk (above the cutoff) eSAS groups according to the cutoff score with optimal accuracy of eSAS for major morbidity. Univariable and multivariable regression analysis were used to define risk factors of the occurrence of major morbidity.

RESULTS

Of 189 patients, 110 patients developed major morbidities (58.2%) and 30-day operative mortality was 5.8% (11/189). There were 156 high risk patients (eSAS ≤7) and 33 low risk (eSAS >7) patients. Univariable analysis demonstrated that forced expiratory volume in one second of predicted (FEV1%) ≤78% (44% vs. 61%, P=0.024), McKeown approach (22.7% vs. 7.6%, P=0.011), duration of operation longer than 230 minutes, intraoperative estimated blood loss (347±263 vs. 500±510 mL, P=0.015) and eSAS ≤7 (62.2% vs. 90.0%, P=0.001) were predictive of major morbidity. Multivariable analysis demonstrated that FEV1% ≤78% (OR, 2.493; 95% CI, 1.279-4.858, P=0.007) and eSAS ≤7 (OR, 2.810; 95% CI, 1.105-7.144; P=0.030) were independent predictors of major morbidity after esophagectomy. Compared with patients who had eSAS >7, patients who had eSAS ≤7 had longer hospital length of stay (25.39±14.36 vs. 32.22±22.66 days, P=0.030). However, there were no significant differences in ICU length of stay, duration of mechanical ventilation, ICU death, 30-day death rate and in-hospital death rate between high risk and low risk patients.

CONCLUSIONS

The eSAS score is predictive of major morbidity, and lower eSAS is associated with longer hospital length of stay in esophageal cancer patients after open esophagectomy.

[Efficacy and mechanism of local delivery of rapamycin and rapamycin-loaded poly(lactic-co-glycolic) acid nanoparticles on coronary restenosis of injury-stenosis model of minipigs]

OBJECTIVE

To determine whether intramural administration of rapamycin (RPM)-loaded polylactic-polyglycolic acid (PLGA) nanoparticles (NPs) can reduce intimal thickening and affect the mRNA expressions of matrix metalloproteinase (MMP)-2, tissue inhibitor of metalloproteinase (TIMP)-2 and p27(kipl) in a coronary injury-stenosis model of minipigs.

METHODS

Twenty eight minipigs were randomly separated into four groups: saline group (n=7), blank PLGA NPs group (5.0 mg/ml)(n=7), RPM group (1.0 mg/ml)(n=7), and RPM-PLGA NPs(5.0 mg/ml)group (n=7), respectively. Different treatments were intracoronary locally delivered via a Dispatch™ catheter for 10 minutes. Serial angiography was performed pre-and post-modeling 30 days and the percent stenosis degree was assessed. Hematoxylin-Eosin (HE) staining, Weigert's resorcin fuchsin staining and picric acid-sirius red staining were used for morphometric analysis. Immunohistochemistry was performed to assess the levels of proliferating cell nuclear antigen (PCNA), MMP-2, and TIMP-2 at early and late time points, respectively. The expression of p27(kip1) mRNA was detected by in situ hybridization staining.

RESULTS

Data from 21 minipigs had been collected at the end of the experiment with 6, 4, 5, and 6 from the former mentioned 4 groups, respectively. For the instant injury index, there was no significant difference among the four groups. The percent stenosis degree of RPM-PLGA NPs group was significantly lower than that of the other three groups respectively (all P< 0.05). The neointima area, net external elastic lamina area to external elastic laminal area ratio, and proliferative index of RPM-PLGA NPs group were significantly less than those of the other three groups, with all the P values less than 0.05. The mean value of integral optical density of p27(kip1)mRNA expression of RPM-PLGA group was 0.35 ± 0.06, higher than that of blank PLGA NPs group (0.12 ± 0.05, P< 0.01), saline group (0.16 ± 0.03, P< 0.05), and RPM group (0.15 ± 0.03, P< 0.05), respectively. The MMP-2/TIMP-2 ratio and the positive expression index of PCNA in RPM-PLGA group were lower than that of the other groups (P< 0.05).

CONCLUSIONS

Locally delivered rapamycin-loaded PLGA NPs significantly reduces MMP-2/TIMP-2 ratio and PCNA expression, increases p27(kip1) mRNA expression and significantly relieves percent stenosis degree and shows excellent acute procedural results in the minipig interventional coronary artery oversized balloon injury model. The results from minipig model further support that this approach could be a potential clinical procedure for vascular proliferative disease.

Assessment of a predictive score for pulmonary complications in cancer patients after esophagectomy

BACKGROUND

Esophagectomy is a very important method for the treatment of resectable esophageal cancer, which carries a high rate of morbidity and mortality. This study was undertaken to assess the predictive score proposed by Ferguson et al for pulmonary complications after esophagectomy for patients with cancer.

METHODS

The data of patients who admitted to the intensive care unit after transthoracic esophagectomy at Cancer Hospital of Chinese Academy of Medical Sciences and Peking Union Medical College between September 2008 and October 2010 were retrospectively reviewed.

RESULTS

Two hundred and seventeen patients were analyzed and 129 (59.4%) of them had postoperative pulmonary complications. Risk scores varied from 0 to 12 in all patients. The risk scores of patients with postoperative pulmonary complications were higher than those of patients without postoperative pulmonary complications (7.27±2.50 vs. 6.82±2.67; P=0.203). There was no significant difference in the incidence of postoperative pulmonary complications as well as in the increase of risk scores (χ (2)=5.477, P=0.242). The area under the curve of predictive score was 0.539±0.040 (95%CI 0.461 to 0.618; P=0.324) in predicting the risk of pulmonary complications in patients after esophagectomy.

CONCLUSION

In this study, the predictive power of the risk score proposed by Ferguson et al was poor in discriminating whether there were postoperative pulmonary complications after esophagectomy for cancer patients.

Specific alterations in plasma proteins during depressed, manic, and euthymic states of bipolar disorder

Bipolar disorder (BD) is a common psychiatric mood disorder affecting more than 1-2% of the general population of different European countries. Unfortunately, there is no objective laboratory-based test to aid BD diagnosis or monitor its progression, and little is known about the molecular basis of BD. Here, we performed a comparative proteomic study to identify differentially expressed plasma proteins in various BD mood states (depressed BD, manic BD, and euthymic BD) relative to healthy controls. A total of 10 euthymic BD, 20 depressed BD, 15 manic BD, and 20 demographically matched healthy control subjects were recruited. Seven high-abundance proteins were immunodepleted in plasma samples from the 4 experimental groups, which were then subjected to proteome-wide expression profiling by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight tandem mass spectrometry. Proteomic results were validated by immunoblotting and bioinformatically analyzed using MetaCore. From a total of 32 proteins identified with 1.5-fold changes in expression compared with healthy controls, 16 proteins were perturbed in BD independent of mood state, while 16 proteins were specifically associated with particular BD mood states. Two mood-independent differential proteins, apolipoprotein (Apo) A1 and Apo L1, suggest that BD pathophysiology may be associated with early perturbations in lipid metabolism. Moreover, down-regulation of one mood-dependent protein, carbonic anhydrase 1 (CA-1), suggests it may be involved in the pathophysiology of depressive episodes in BD. Thus, BD pathophysiology may be associated with early perturbations in lipid metabolism that are independent of mood state, while CA-1 may be involved in the pathophysiology of depressive episodes.

Performance of three prognostic models in patients with cancer in need of intensive care in a medical center in China

Objective

The aim of this study was to evaluate the performance of Acute Physiology and Chronic Health Evaluation II (APACHE II), Simplified Acute Physiology Score 3 (SAPS 3), and Acute Physiology and Chronic Health Evaluation IV (APACHE IV) in patients with cancer admitted to intensive care unit (ICU) in a single medical center in China.

Materials and Methods

This is a retrospective observational cohort study including nine hundred and eighty one consecutive patients over a 2-year period.

Results

The hospital mortality rate was 4.5%. When all 981 patients were evaluated, the area under the receiver operating characteristic curve (AUROC, 95% Confidential Intervals) of the three models in predicting hospital mortality were 0.948 (0.914–0.982), 0.863 (0.804–0.923), and 0.873 (0.813–0.934) for SAPS 3, APACHE II and APACHE IV respectively. The p values of Hosmer-Lemeshow statistics for the models were 0.759, 0.900 and 0.878 for SAPS 3, APACHE II and APACHE IV respectively. However, SAPS 3 and APACHE IV underestimated the in-hospital mortality with standardized mortality ratio (SMR) of 1.5 and 1.17 respectively, while APACHE II overestimated the in-hospital mortality with SMR of 0.72. Further analysis showed that discrimination power was better with SAPS 3 than with APACHE II and APACHE IV whether for emergency surgical and medical patients (AUROC of 0.912 vs 0.866 and 0.857) or for scheduled surgical patients (AUROC of 0.945 vs 0.834 and 0.851). Calibration was good for all models (all p > 0.05) whether for scheduled surgical patients or emergency surgical and medical patients. However, in terms of SMR, SAPS 3 was both accurate in predicting the in-hospital mortality for emergency surgical and medical patients and for scheduled surgical patients, while APACHE IV and APACHE II were not.

Conclusion

In this cohort, we found that APACHE II, APACHE IV and SAPS 3 models had good discrimination and calibration ability in predicting in-hospital mortality of critically ill patients with cancer in need of intensive care. Of these three severity scores, SAPS 3 was superior to APACHE II and APACHE IV, whether in terms of discrimination and calibration power, or standardized mortality ratios.

Effect of sedation on short-term and long-term outcomes of critically ill patients with acute respiratory insufficiency

BACKGROUND

The present study aimed to determine the short-term and long-term outcomes of critically ill patients with acute respiratory insufficiency who had received sedation or no sedation.

METHODS

The data of 91 patients who had received mechanical ventilation in the first 24 hours between November 2008 and October 2009 were retrospectively analyzed. These patients were divided into two groups: a sedation group (n=28) and a non-sedation group (n=63). The patients were also grouped in two groups: deep sedation group and daily interruption and /or light sedation group.

RESULTS

Overall, the 91 patients who had received ventilation ≥48 hours were analyzed. Multivariate analysis demonstrated two independent risk factors for in-hospital death: sequential organ failure assessment score (P=0.019, RR 1.355, 95%CI 1.051-1.747, B=0.304, SE=0.130, Wald=50483) and sedation (P=0.041, RR 5.015, 95%CI 1.072-23.459, B=1.612, SE=0.787, Wald=4.195). Compared with the patients who had received no sedation, those who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and hospital, and an increased in-hospital mortality rate. The Kaplan-Meier method showed that patients who had received sedation had a lower 60-month survival rate than those who had received no sedation (76.7% vs. 88.9%, Log-rank test=3.630, P=0.057). Compared with the patients who had received deep sedation, those who had received daily interruption or light sedation showed a decreased in-hospital mortality rate (57.1% vs. 9.5%, P=0.008). The 60-month survival of the patients who had received deep sedation was significantly lower than that of those who had daily interruption or light sedation (38.1% vs. 90.5%, Log-rank test=6.783, P=0.009).

CONCLUSIONS

Sedation was associated with in-hospital death. The patients who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and in hospital, and an increased in-hospital mortality rate compared with the patients who did not receive sedation. Compared with daily interruption or light sedation, deep sedation increased the in-hospital mortality and decreased the 60-month survival for patients who had received sedation.

Salt stress represses production of extracellular proteases in Bacillus pumilus

Bacillus pumilus is able to secrete subtilisin-like prote-ases, one of which has been purified and characterized biochemically, demonstrating great potential for use in industrial applications. In the current study, the biosynthesis and transcription of extracellular pro-teases in B. pumilus (BA06) under salt stress were investigated using various methods, including a proteolytic assay, zymogram analysis, and real-time PCR. Our results showed that total extracellular proteolytic activity, both in fermentation broth and on milk-containing agar plates, was considerably repressed by salt in a dosage-dependent manner. As Bacillus species usually secret multiple extracellular proteases, a vari-ety of individual extracellular protease encoding genes were selected for real-time PCR analysis. It was shown that proteases encoded by the aprE and aprX genes were the major proteases in the fermentation broth in terms of their transcripts in B. pumilus. Further, transcription of aprE, aprX, and epr genes was indeed repressed by salt stress. In con-trast, transcription of other genes (e.g., vpr and wprA) was not repressed or significantly affected by the salt. Conclusively, salt stress represses total extracellular proteolytic activity in B. pumilus, which can largely be ascribed to suppression of the major protease-encoding genes (aprE, aprX) at the transcriptional level. In contrast, transcription of other pro-tease-encoding genes (e.g., vpr, wprA) was not repressed by salt stress.

Two acute kidney injury risk scores for critically ill cancer patients undergoing non-cardiac surgery

BACKGROUND

Several risk scoures have been used in predicting acute kidney injury (AKI) of patients undergoing general or specific operations such as cardiac surgery. This study aimed to evaluate the use of two AKI risk scores in patients who underwent non-cardiac surgery but required intensive care.

METHODS

The clinical data of patients who had been admitted to ICU during the first 24 hours of ICU stay between September 2009 and August 2010 at the Cancer Institute, Chinese Academy of Medical Sciences & Peking Union Medical College were retrospectively collected and analyzed. AKI was diagnosed based on the acute kidney injury network (AKIN) criteria. Two AKI risk scores were calculated: Kheterpal and Abelha factors.

RESULTS

The incidence of AKI was 10.3%. Patients who developed AKI had a increased ICU mortality of 10.9% vs. 1.0% and an in-hospital mortality of 13.0 vs. 1.5%, compared with those without AKI. There was a significant difference between the classification of Kheterpal's AKI risk scores and the occurrence of AKI (P<0.001). There was no significant difference between the number of Abelha's AKI risk scores and the occurrence of AKI (P=0.499). Receiver operating characteristic curves demonstrated an area under the curve of 0.655±0.043 (P=0.001, 95% confidence interval: 0.571-0.739) for Kheterpal's AKI risk score and 0.507±0.044 (P=0.879, 95% confidence interval: 0.422-0.592) for Abelha's AKI risk score.

CONCLUSION

Kheterpal's AKI risk scores are more accurate than Abelha's AKI risk scores in predicting the occurrence of AKI in patients undergoing non-cardiac surgery with moderate predictive capability.

Risk factors and prognosis of critically ill cancer patients with postoperative acute respiratory insufficiency

BACKGROUND

This study aimed to investigate the risk factors and outcome of critically ill cancer patients with postoperative acute respiratory insufficiency.

METHODS

The data of 190 critically ill cancer patients with postoperative acute respiratory insufficiency were retrospectively reviewed. The data of 321 patients with no acute respiratory insufficiency as controls were also collected. Clinical variables of the first 24 hours after admission to intensive care unit were collected, including age, sex, comorbid disease, type of surgery, admission type, presence of shock, presence of acute kidney injury, presence of acute lung injury/acute respiratory distress syndrome, acute physiologic and chronic health evaluation (APACHE II) score, sepsis-related organ failure assessment (SOFA), and PaO2/FiO2 ratio. Duration of mechanical ventilation, length of intensive care unit stay, intensive care unit death, length of hospitalization, hospital death and one-year survival were calculated.

RESULTS

The incidence of acute respiratory insufficiency was 37.2% (190/321). Multivariate logistic analysis showed a history of chronic obstructive pulmonary diseases (P=0.001), surgery-related infection (P=0.004), hypo-volemic shock (P<0.001), and emergency surgery (P=0.018), were independent risk factors of postoperative acute respiratory insufficiency. Compared with the patients without acute respiratory insufficiency, the patients with acute respiratory insufficiency had a prolonged length of intensive care unit stay (P<0.001), a prolonged length of hospitalization (P=0.006), increased intensive care unit mortality (P=0.001), and hospital mortality (P<0.001). Septic shock was shown to be the only independent prognostic factor of intensive care unit death for the patients with acute respiratory insufficiency (P=0.029, RR: 8.522, 95%CI: 1.243-58.437, B=2.143, SE=0.982, Wald=4.758). Compared with the patients without acute respiratory insufficiency, those with acute respiratory insufficiency had a shortened one-year survival rate (78.7% vs. 97.1%, P<0.001).

CONCLUSION

A history of chronic obstructive pulmonary diseases, surgery-related infection, hypovolemic shock and emergency surgery were risk factors of critically ill cancer patients with postoperative acute respiratory insufficiency. Septic shock was the only independent prognostic factor of intensive care unit death in patients with acute respiratory insufficiency. Compared with patients without acute respiratory insufficiency, those with acute respiratory insufficiency had adverse short-term outcome and a decreased one-year survival rate.

Prognosis of patients with shock receiving vasopressors

BACKGROUND

Consensus guidelines suggested that both dopamine and norepinephrine may be used, but specific doses are not recommended. The aim of this study is to determine the predictive role of vasopressors in patients with shock in intensive care unit.

METHODS

One hundred and twenty-two patients, who had received vasopressors for 1 hour or more in intensive care unit (ICU) between October 2008 and October 2011, were included. There were 85 men and 37 women, with a median age of 65 years (55-73 years). Their clinical data were retrospectively collected and analyzed.

RESULTS

The median simplified acute physiological score 3 (SAPS 3) was 50 (42-55). Multivariate analysis showed that septic shock (P=0.018, relative risk: 4.094; 95% confidential interval: 1.274-13.156), SAPS 3 score at ICU admission (P=0.028, relative risk: 1.079; 95% confidential interval: 1.008-1.155), and norepinephrine administration (P<0.001, relative risk: 9.353; 95% confidential interval: 2.667-32.807) were independent predictors of ICU death. Receiver operating characteristic curve analysis demonstrated that administration of norepinephrine ≥0.7 μg/kg per minute resulted in a sensitivity of 75.9% and a specificity of 90.3% for the likelihood of ICU death. In patients who received norepinephrine ≥0.7 μg/kg per minute there was more ICU death (71.4% vs. 44.8%) and in-hospital death (76.2% vs. 48.3%) than in those who received norepinephrine <0.7 μg/kg per minute. These patients had also a decreased 510-day survival rate compared with those who received norepinephrine <0.7 μg/kg per minute (19.2% vs. 64.2%).

CONCLUSION

Septic shock, SAPS 3 score at ICU admission, and norepinephrine administration were independent predictors of ICU death for patients with shock. Patients who received norepinephrine ≥0.7 μg/kg per minute had an increased ICU mortality, an increased in-hospital mortality, and a decreased 510-day survival rate.

Atomic-scale mechanisms of the glass-forming ability in metallic glasses

The issue, composition dependence of glass-forming ability (GFA) in metallic glasses (MG), has been investigated by systematic experimental measurements coupled with theoretical calculations in Cu-Zr and Ni-Nb alloy systems. It is found that the atomic-level packing efficiency strongly relates to their GFA. The best GFA is located at the largest difference in the packing efficiency of the solute-centered clusters between the glassy and crystal alloys in both MG systems. This work provides an understanding of GFA from atomic level and will shed light on the development of new MGs with larger critical sizes.

Identification of potential hosts and vectors of scrub typhus and tick-borne spotted fever group rickettsiae in eastern Taiwan

Scrub typhus and tick-borne spotted fever group (SFG) rickettsioses are transmitted by chiggers (larval trombiculid mites) and hard ticks, respectively. We assessed exposure to these disease vectors by extensively sampling both chiggers and ticks and their small mammal hosts in eastern Taiwan during 2007 and 2008. The striped field mouse Apodemus agrarius Pallas (Rodentia: Muridae) was the most common of the small mammals (36.1% of 1393 captures) and presented the highest rate of infestation with both chiggers (47.8% of 110 760) and ticks (78.1% of 1431). Leptotrombidium imphalum Vercammen-Grandjean & Langston (Trombidiformes: Trombiculidae) and immature Rhipicephalus haemaphysaloides Supino (Ixodida: Ixodidae) were the most abundant chiggers (84.5%) and ticks (>99%) identified, respectively. Immunofluorescent antibody assay revealed high seropositive rates of rodents against Orientia tsutsugamushi Hyashi (Rickettsiales: Rickettsiaceae), the aetiological agent of scrub typhus (70.0% of 437 rodents), and tick-borne SFG rickettsiae (91.9% of 418 rodents). The current study represents a first step towards elucidating the potential hosts and vectors in the enzootic transmission of O. tsutsugamushi and tick-borne SFG rickettsiae in Taiwan. Further studies should focus on characterizing pathogens in L. imphalum and R. haemaphysaloides, as well as the proclivity of both vectors to humans. Uncovering the main hosts of adult ticks is also critical for the prevention of SFG rickettsial infections.

Lack of association between AKT1 variances versus clinical manifestations and social function in patients with schizophrenia

The elucidation of genotype-phenotype relationships in psychiatric research is at an early stage. V-akt murine thymoma viral oncogene homolog 1 (AKT1) is a serine/threonine kinase known as protein kinase B. Emerging studies have implicated the role of AKT1 in pathogenesis of schizophrenia; however, the findings have not been consistent. This study aims to examine the association of AKT1 polymorphisms with drug-free and post-treatment symptomatology and social function in patients with schizophrenia. One hundred and twenty newly hospitalised patients with acutely exacerbated schizophrenia who had never been treated by atypical antipsychotics were recruited. They received optimal treatment of risperidone for up to 42 days in the inpatient research unit. Clinical manifestations were monitored by Positive and Negative Syndrome Scale (PANSS) and social function by Nurses' Observation Scale for Inpatients Evaluation (NOSIE). Patients were genotyped for eight AKT1 Single Nucleotide Polymorphism (SNPs), which have been previously investigated for association with schizophrenia. At drug-free status and after best possible treatment of risperidone, genotypes of each SNP did not influence performances in NOSIE, PANSS-total, -positive, -negative and -general psychopathology profiles. These results suggest that AKT1 does not play a significant role in clinical and functional manifestations in patients with schizophrenia who receive risperidone treatment. Future research should also focus on the relationships between genotypes of other susceptibility genes and phenotypes or functional outcomes of schizophrenia.

Botulinum Toxins Inhibit the Antidiuretic Hormone (ADH)-Stimulated Increase in Rabbit Cortical Collecting-Tubule Water Permeability

The mammalian renal collecting duct increases its water permeability in response to antidiuretic hormone (ADH). ADH causes cytoplasmic endosomes containing the water channel, aquaporin 2 (AQP 2), to fuse with the apical membrane so that the water permeability of the tubule increases many times above baseline. SNARE proteins are involved in the docking and fusion of vesicles with the cell membrane in neuron synapses. Whether these proteins are involved in the fusion of vesicles to the cell membrane in other tissues is not entirely clear. In the present study, we examined the role of SNARE proteins in the insertion of water channels in the collecting-duct response to ADH by using botulinum toxins A, B and C. Toxins isolated from clostridium botulinum are specific proteases that cleave different SNARE proteins and inactivate them. Tubules were perfused in vitro with botulinum toxin in the perfusate (50 nM for A and B and 15 nM for C). ADH (200 pM) was then added to the bath after baseline measurements of osmotic water permeability (P(f)) and the change in P(f) was followed for one hour. Botulinum toxins significantly inhibited the maximum P(f) by approximately 50%. Botulinum toxins A and C also decreased the rate of rise of P(f). Thus, SNARE proteins are involved in the insertion of the water channels in the collecting duct.

Factors associated with women's and children's body mass indices by income status

OBJECTIVE

To describe associations between eating behaviors, dietary intake, physical activity, attitudes toward diet and health, sociodemographic variables and body mass index (BMI) among women and children, and differences by household income.

DESIGN

Data from the 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII) and the Diet and Health Knowledge Survey (DHKS) were examined using multivariate regression to estimate the associations between BMI and behavioral and environmental variables among women and children.

SUBJECTS

CSFII 1994-1996 is representative of the US population. DHKS surveyed CSFII respondents 20 y of age and over. Our samples consisted of 2419 adult women and 1651 school-age children.

MEASUREMENTS

CSFII respondents reported 24 h recalls of all food intakes on 2 nonconsecutive days and their personal and household characteristics, including self-reported height and weight. DHKS collected data on knowledge and attitudes toward dietary guidance and health from CSFII adult respondents.

RESULTS

Significant correlations between women's BMI and age, race, dietary patterns, TV watching, and smoking was observed among women from both low- and high-income households. Beverage consumption, eating out, the importance of maintaining healthy weight, and exercise were correlated with BMI only among women from high-income households. Among children, age, race, income, and mother's BMI were significantly correlated with child BMI.

CONCLUSIONS

Among women, the associations between some behavioral and environmental factors and BMI differ by household income. Intervention programs need to target specific eating and physical activity behaviors to promote a healthy body weight.

Effects of premature stimulation on HERG K(+) channels

1. The unusual kinetics of human ether-à-go-go-related gene (HERG) K(+) channels are consistent with a role in the suppression of arrhythmias initiated by premature beats. Action potential clamp protocols were used to investigate the effect of premature stimulation on HERG K(+) channels, transfected in Chinese hamster ovary cells, at 37 degrees C. 2. HERG K(+) channel currents peaked during the terminal repolarization phase of normally paced action potential waveforms. However, the magnitude of the current and the time point at which conductance was maximal depended on the type of action potential waveform used (epicardial, endocardial, Purkinje fibre or atrial). 3. HERG K(+) channel currents recorded during premature action potentials consisted of an early transient outward current followed by a sustained outward current. The magnitude of the transient current component showed a biphasic dependence on the coupling interval between the normally paced and premature action potentials and was maximal at a coupling interval equivalent to 90 % repolarization (APD(90)) for ventricular action potentials. The largest transient current response occurred at shorter coupling intervals for Purkinje fibre (APD(90) - 20 ms) and atrial (APD(90) - 30 ms) action potentials. 4. The magnitude of the sustained current response following premature stimulation was similar to that recorded during the first action potential for ventricular action potential waveforms. However, for Purkinje and atrial action potentials the sustained current response was significantly larger during the premature action potential than during the normally paced action potential. 5. A Markov model that included three closed states, one open and one inactivated state with transitions permitted between the pre-open closed state and the inactivated state, successfully reproduced our results for the effects of premature stimuli, both during square pulse and action potential clamp waveforms. 6. These properties of HERG K(+) channels may help to suppress arrhythmias initiated by early afterdepolarizations and premature beats in the ventricles, Purkinje fibres or atria.

MRI analysis of right ventricular function in normal and spontaneously hypertensive rats

Right ventricular structure and function were characterized in spontaneously hypertensive rats (SHR) using non-invasive magnetic resonance imaging (MRI) techniques. These studies therefore complement previous reports preoccupied with left ventricular changes associated with this condition. Eight SHR and eight control normotensive Wistar-Kyoto (WKY) rats were each subdivided into equal age-matched groups of 8 and 12 weeks. The right ventricle was imaged through a series of twelve contiguous 1.37-1.75 mm transverse sections at twelve equally spaced time-points that covered both systole and most of diastole thereby completely reconstructing right ventricular anatomy. This gave measurements of right ventricular myocardial mass that were consistent through all twelve time-points in all four experimental groups throughout their cardiac cycles. However, spontaneous hypertension increased this right ventricular myocardial mass, as well as the end-diastolic (EDV) and end-systolic volumes (ESV). Although stroke volume (SV) was conserved, decreases in ejection fraction (EF), a positive shift in the relationship between SV and EDV, and reduced indices of systolic ejection rates in SHR rats compared with the age-matched normal WKY controls indicated significant systolic dysfunction. Additionally, reductions in the rates of diastolic relaxation suggested the onset of diastolic dysfunction. Thus, the non-invasive nature of MRI has made it possible for the first time to demonstrate alterations in structure of the right ventricle and in quantitative indicators of its systolic and diastolic function in the SHR model of hypertension.

Diffusion-weighted MRI used to detect in vivo modulation of cortical spreading depression: comparison of sumatriptan and tonabersat

Spreading cortical depolarization and depression of electroencephalographic activity (SD) may underlie the aura and spreading neurovascular events of migraine. Cortical depolarization may also precipitate the progressive development of cerebral pathology following ischemia. However, data on SD in the human brain are sparse, most likely reflecting the technical difficulties involved in performing such clinical studies. We have previously shown that the transient cerebral water disturbances during SD can be quantitatively investigated in the gyrencephalic brain using repetitive diffusion-weighted magnetic resonance imaging (DWI). To investigate whether DWI could detect modulation of the spatiotemporal properties of SD in vivo, the effects of the antimigraine drug sumatriptan (0.3 mg/kg iv) and the novel anticonvulsant tonabersat (10 mg/kg ip) were evaluated in the cat brain. Supporting previous findings, sumatriptan did not affect the numbers of events (range, 4-8), the duration of SD activity (39.8 +/- 4.4 min, mean +/- SEM), and event velocity (2.2 +/- 0.4 mm min(-1)); tonabersat significantly reduced SD event initiation (range, 0-3) and duration (13.2 +/- 5.0 min) and increased primary event velocity (5.4 +/- 0.7 mm min(-1)). However, both drugs significantly decreased, by >50%, the spatial extent of the first KCl-evoked SD event, and sumatriptan significantly increased event propagation across the suprasylvian sulcus (5.5 +/- 0.6 vs 2.4 +/- 0.4 events in controls). These results demonstrate (1) the feasibility of using DWI to evaluate therapeutic effects on SD, and (2) that sumatriptan may directly modulate the spatial distribution of SD activity in the gyrencephalic brain.

Detection of pharmacologically mediated changes in cerebral activity by functional magnetic resonance imaging: the effects of sulpiride in the brain of the anaesthetised rat

Blood oxygenation level dependent (BOLD) contrast functional magnetic resonance imaging (fMRI) was used to study the effects of the D(2)-like receptor selective antagonist, sulpiride, at 2 Tesla in the brain of the alpha-chloralose anaesthetised rat. Region of interest (ROI) analysis indicated significant (P<0.05) bilateral increases in BOLD signal intensity in the frontal cortex following a single administration of sulpiride (10 mg/kg i.v.). BOLD signal changes were slow in onset and increased gradually during the experiment, reaching 8.0+/-0.5% (mean+/-S.E.M.) above pre-injection control values 165 min after drug administration. Signal increases remained high at the experiment end (3 h post sulpiride administration). Sulpiride (30 mg/kg i.v.) had a similar effect in the frontal cortex, increasing signal 5.2+/-1.8% above control values by 174 min; its effects were, however, more variable between rats, and were not statistically significant. Sulpiride (3 mg/kg i.v.) had no significant effect upon BOLD signal intensity in any brain region. No dose of sulpiride resulted in any significant BOLD signal changes in the striatum or cerebellum. These data are supportive of the notion that sulpiride causes an increase in frontal dopaminergic function by antagonism of presynaptically located dopamine D(2) receptors in this brain region, consistent with its therapeutic action. Furthermore, the utility of BOLD contrast fMRI as a means of detecting changes in neuronal activity contingent upon the administration of a psychoactive pharmacological agent has been demonstrated.

Calcium waves induced by hypertonic solutions in intact frog skeletal muscle fibres

1. Regenerative Ca2+ waves and oscillations indicative of calcium-induced calcium release (CICR) activity were induced in fully polarized, fluo-3-loaded, intact frog skeletal muscle fibres by exposure to hypertonic Ringer solutions. 2. The calcium waves persisted in fibres exposed to EGTA-containing solutions, during sustained depolarization of the membrane potential or following treatment with the dihydropyridine receptor (DHPR)-blocker nifedipine. 3. The waves were blocked by the ryanodine receptor (RyR)-specific agents ryanodine and tetracaine, and potentiated by caffeine. 4. In addition to these pharmacological properties, the amplitudes, frequency and velocity of such hypertonicity-induced waves closely resembled those of Ca2+ waves previously described in dyspedic skeletal myocytes expressing the cardiac RyR-2. 5. Quantitative transmission and freeze-fracture electronmicroscopy demonstrated a reversible cell shrinkage, transverse (T)-tubular luminal swelling and decreased T-sarcoplasmic reticular (SR) junctional gaps in fibres maintained in and then fixed using hypertonic solutions. 6. The findings are consistent with a hypothesis in which RyR-Ca2+ release channels can be partially liberated from their normal control by T-tubular DHPR-voltage sensors in hypertonic solutions, thereby permitting CICR to operate even in such fully polarized skeletal muscle fibres.

Mapping of brain activation in response to pharmacological agents using fMRI in the rat

Functional MRI (fMRI) was used to investigate the effects of psychotropic compound activity in the rat brain in vivo. The effects of dizocilpine (MK-801) an N-methyl-D-aspartate receptor antagonist and m-chlorophenylpiperazine (mCPP), a 5-HT(2b/2c)-receptor agonist on rat brain activity were investigated over a time interval of about 1 h and the results were compared to published glucose utilisation and cerebral blood flow data. Signal magnitude increases were observed predominantly in limbic regions following MK-801 administration (0.5 mg/kg i.v) whereas signal decreases were restricted to neocortical areas; a characteristic, time dependent pattern of regional changes evolved from the thalamic nuclei to cortical regions. In contrast, mCPP (25 mg/kg i.p) produced gradual signal intensity increases in limbic and motor regions with signal decreases restricted to the visual, parietal and motor cortices. The results from both compounds show remarkable similarity with autoradiographic measurements of cerebral blood flow and glucose uptake. These experiments suggest that the spatio-temporal capabilities of fMRI may be applied to the in vivo investigation of psychoactive compound activity with potential for clinical applications.

Normal conduction of surface action potentials in detubulated amphibian skeletal muscle fibres

1. The influence of the transverse (T) tubules on surface action potential conduction was investigated by comparing electrophysiological and confocal microscopic assessments of tubular changes in osmotically shocked and control fibres from frog sartorius muscle. 2. The membrane-impermeant fluorescent dye, di-8-ANEPPs spread readily from the bathing extracellular solution into the tubular membranes in control, intact fibres. Prior exposure of muscles to a hypertonic glycerol-Ringer solution, its replacement by an isotonic Ca(2+)-Mg(2+) Ringer solution and cooling sharply reduced such access. In contrast, dye application in the course of this osmotic shock procedure stained the large tubular vacuoles hitherto associated with successful muscle detubulation. 3. Conduction velocities in intact, control fibres (1.91 +/- 0.048 m s(-1), mean +/- S.E.M., n = 32 fibres) agreed with earlier values reported at room temperature (18-21 degrees C) and were unaffected by prior episodes of steady cooling to 8-10 degrees C (1.91 +/- 0.043 m s(-1), n = 30). 4. Cooling to 11.5 degrees C reduced these velocities (1.47 +/- 0.081 m s(-1), n = 25) but action potential waveforms still included early overshoots and the delayed after-depolarizations associated with tubular electrical activity. 5. In contrast, action potentials from cooled, superficial fibres in osmotically shocked muscles lacked after-depolarization phases implying tubular detachment. Their mean conduction velocities (1.62 +/- 0.169 m s(-1), n = 25) were not significantly altered from values obtained in untreated controls or in intact fibres in muscle similarly treated with glycerol, in direct contrast to earlier results. 6. Cooling produced similar reductions in maximum rates of voltage change dV/dt in action potentials from all fibre groups with lower rates of change shown by detubulated fibres. 7. Use of an antibody to a conserved epitope of the alpha-subunit of voltage-gated sodium channels suggested a concentration of sodium channels close to the mouths of the T tubules. 8. These electrophysiological and anatomical findings are consistent with a partial independence of electrical events in the transverse tubules from those responsible for the rapid conduction of surface regenerative activity. 9. The findings are discussed in terms of a partial separation of the electrical activity propagated over the surface membrane, from the initiation of propagated activity within the T tubules, by the triggering of the sodium channels clustered selectively around the mouths of the T tubules.

Regulation of ROMK trafficking and channel activity

ROMK potassium channels are present in the thick ascending limbs and cortical collecting ducts of the kidney and are responsible for potassium ion efflux in these segments. ROMK channels are regulated by multiple signalling pathways. This review focuses on recent advances in the regulation of ROMK channels by phosphatidylinositol-4,5-bisphosphate and by membrane trafficking. Relevant publications on the related inward rectifier potassium channels will also be discussed.

The association of K-ras gene mutation and vascular endothelial growth factor gene expression in pancreatic carcinoma

BACKGROUND

Previously, the authors reported the role of the vascular endothelial growth factor (VEGF) as an angiogenic factor in 40 patients with pancreatic carcinoma. In this study, they investigated the mechanism underlying the regulation of VEGF gene expression and evaluated VEGF expression and K-ras gene status in 48 patients with pancreatic carcinoma.

METHODS

The authors used quantitative reverse transcriptase-polymerase chain reaction analysis and direct sequencing techniques for a retrospective study of VEGF gene expression and K-ras gene status in tumor tissue samples from 48 patients with pancreatic carcinoma. Immunohistochemistry also was used to investigate VEGF protein expression.

RESULTS

Thirty-one tumors (64.6%) were evaluated with high VEGF expression, and 17 tumors (35.4%) were evaluated with low VEGF expression. Of the 48 primary pancreatic tumors studied, 33 tumors (68.8%) contained mutations of the K-ras gene. There was a significant correlation between VEGF expression and K-ras status. Twenty-five of 33 tumors (75.8%) with mutant K-ras genes showed high VEGF expression, whereas only 6 of 15 tumors with the wild type K-ras (40.0%) showed high VEGF expression (P = 0.038). The mean (+/- standard error) VEGF conservation rate for the 33 tumors with mutant K-ras was 1.839 +/- 1.241, and that for the 15 tumors with wild type K-ras was 1.057 +/- 0.983 (P = 0.037). Furthermore, the median survival for patients with mutant K-ras was shorter than for those with wild type K-ras (10.6 months vs. 27.6 months, respectively; P = 0.026), whereas the median survival for patients with high VEGF expression was shorter compared with that for patients with low VEGF expression (9.5 months vs. 26.4 months, respectively; P = 0.002). Cox regression model analysis indicated that only the VEGF status was a significant factor for prognosis (P = 0.024). Other variables, i.e., K-ras status, histopathologic tumor grade, tumor status, lymph node status, metastatic status, gender, and age at surgery, were not significant.

CONCLUSIONS

The results of this study suggest that K-ras oncogene mutation may be associated with VEGF expression and that patients with pancreatic carcinoma who have high VEGF expression are associated with a poor prognosis.

[Evaluation of clinical application of intravascular ultrasound image]

OBJECTIVE

To prospectively evaluate the clinical applications of intravascular ultrasound (IVUS).

METHODS

Four hundred and thirty seven patients with coronary artery disease (CAD) or suspect CAD were imaged with CAD and IVUS, including (1) assessment IVUS in 135 cases with normal coronary angiography (CAG) (2) comparison IVUS with CAG pre and after angioplasty in 52 patients with CAD (3) assessment of detecting calcification lesions with CAG and IVUS in 150 patients (4) predicting the cardiac events after stent implantation guided by IVUS (n = 47) and CAG (N = 53).

RESULTS

IVUS may detect coronary atherosclerosis lesions with normal by CAG. CAG overestimated effect of angioplasty. IVUS was more accurate to determine effect and complications of PTCA compared with CAG. IVUS interpreted the mechanism of vessel dilatation in PTCA. The cardiac events after stent implantation were significantly reduced after IVUS examination as compared with CAG.

CONCLUSIONS

IVUS represents a radically different approach to vascular anatomy. Unlike angiography, which displays the coronary artery as a silhouette of the contrast-filled lumen, IVUS generates a cross-sectional tomographic image of the lumen and vessel wall. IVUS plays an important role as a guidance in cardiac intervention.

The association of K-ras gene mutation and vascular endothelial growth factor gene expression in pancreatic carcinoma

BACKGROUND

Previously, the authors reported the role of the vascular endothelial growth factor (VEGF) as an angiogenic factor in 40 patients with pancreatic carcinoma. In this study, they investigated the mechanism underlying the regulation of VEGF gene expression and evaluated VEGF expression and K-ras gene status in 48 patients with pancreatic carcinoma.

METHODS

The authors used quantitative reverse transcriptase-polymerase chain reaction analysis and direct sequencing techniques for a retrospective study of VEGF gene expression and K-ras gene status in tumor tissue samples from 48 patients with pancreatic carcinoma. Immunohistochemistry also was used to investigate VEGF protein expression.

RESULTS

Thirty-one tumors (64.6%) were evaluated with high VEGF expression, and 17 tumors (35.4%) were evaluated with low VEGF expression. Of the 48 primary pancreatic tumors studied, 33 tumors (68.8%) contained mutations of the K-ras gene. There was a significant correlation between VEGF expression and K-ras status. Twenty-five of 33 tumors (75.8%) with mutant K-ras genes showed high VEGF expression, whereas only 6 of 15 tumors with the wild type K-ras (40.0%) showed high VEGF expression (P = 0.038). The mean (+/- standard error) VEGF conservation rate for the 33 tumors with mutant K-ras was 1.839 +/- 1.241, and that for the 15 tumors with wild type K-ras was 1.057 +/- 0.983 (P = 0.037). Furthermore, the median survival for patients with mutant K-ras was shorter than for those with wild type K-ras (10.6 months vs. 27.6 months, respectively; P = 0.026), whereas the median survival for patients with high VEGF expression was shorter compared with that for patients with low VEGF expression (9.5 months vs. 26.4 months, respectively; P = 0.002). Cox regression model analysis indicated that only the VEGF status was a significant factor for prognosis (P = 0.024). Other variables, i.e., K-ras status, histopathologic tumor grade, tumor status, lymph node status, metastatic status, gender, and age at surgery, were not significant.

CONCLUSIONS

The results of this study suggest that K-ras oncogene mutation may be associated with VEGF expression and that patients with pancreatic carcinoma who have high VEGF expression are associated with a poor prognosis.

MR diffusion tensor imaging of white matter tract disruption in stroke at 3 T

Recent advances in MR diffusion weighted imaging (DWI) enable the identification of anisotropic white matter tracts with diffusion tensor imaging (DTI). We aimed to use a novel DTI technique to safely study patients with recent stroke in a high field (3 T) MR machine with its intrinsically higher spatial resolution and signal-to-noise ratio. Of ten patients studied, six had disruption of white matter tracts as determined by DTI. A further patient had distortion of white matter tracts around an infarct rather than actual disruption of the tracts themselves. The lack of tract destruction may imply a beneficial prognosis, information that is not available with conventional DWI.

Proteolytic activation of ETK/Bmx tyrosine kinase by caspases

Etk/Bmx is a member of the Btk/Tec family of kinases, which are characterized by having a pleckstrin homology domain at the N terminus, in addition to the Src homology 3 (SH3), SH2, and the catalytic domains, shared with the Src family kinases. Etk, or Btk kinases in general, has been implicated in the regulation of apoptosis. To test whether Etk is the substrate for caspases during apoptosis, in vitro translated [(35)S]methionine-labeled Etk was incubated with different apoptotic extracts and recombinant caspases, respectively. Results showed that Etk was proteolyzed in all conditions tested with identical cleavage patterns. Caspase-mediated cleavage of Etk generated a C-terminal fragment, containing the complete SH2 and tyrosine kinase domains, but without intact pleckstrin homology and SH3 domains. This fragment has 4-fold higher kinase activity than that of the full-length Etk. Ectopic expression of the C-terminal fragment of Etk sensitized the PC3 prostate cancer cells to apoptosis in response to apoptosis-inducing stimuli. The finding, together with an earlier report that Etk is potentially antiapoptotic, suggests that Etk may serve as an apoptotic switch, depending on the forms of Etk existing inside the cells. To our knowledge, this is the first case where the activity of a tyrosine kinase is induced by caspase cleavage.

Identification and Characterization of a Sodium/Calcium Exchanger, NCX-1, in Osteoclasts and Its Role in Bone Resorption

We provide the first demonstration for a Na+/Ca2+ exchanger, NCX-1, in the osteoclast. We speculate that by using Na+ exchange, NCX-1 couples H+ extrusion with Ca2+ fluxes during bone resorption. Microspectrofluorimetry of fura-2-loaded osteoclasts revealed a rapid and sustained, but reversible, cytosolic Ca2+ elevation upon Na+ withdrawal. This elevation was abolished by the cytosolic introduction (by gentle permeabilization) of a highly specific Na+/Ca2+ exchange inhibitor peptide, XIP, but not its inactive analogue, sXIP. Confocal microscopy revealed intense plasma membrane immunofluorescence with an isoform-specific monoclonal anti-NCX-1 antibody applied to gently permeabilized osteoclasts. Electrophysiological studies using excised outside-in membrane patches showed a low-conductance, Na+-selective, dichlorobenzamil-sensitive, amiloride-insensitive channel that we tentatively assigned as being an NCX. Finally, to examine for physiological relevance, an osteoclast resorption (pit) assay was performed. There was a dramatic reduction of bone resorption following NCX-1 inhibition by dichlorobenzamil and XIP (but not with S-XIP). Together, the results suggest that a functional NCX, likely NCX-1, is involved in the regulation of osteoclast cytosolic Ca2+ and bone resorption.

Cortical spreading depression and migraine: new insights from imaging?

The possibility that spreading depression (SD) of cortical activity, a phenomenon observed in all vertebrates, causes the aura of migraine remains an open question in spite of nearly half a century of investigation. SD is also thought to be associated with the progressive neuronal injury observed during cerebral ischaemia. Thus, the ability to detect and investigate SD in humans might prove clinically significant. Animal studies of cortical spreading depression (CSD) have benefited greatly from the advent of relatively non-invasive imaging techniques. The use of these new imaging techniques for clinical studies will accelerate progress in this area of neurobiology.

Activation of protein kinase A and atypical protein kinase C by A(2A) adenosine receptors antagonizes apoptosis due to serum deprivation in PC12 cells

We found in the present study that stimulation of A(2A) adenosine receptors (A(2A)-R) prevents apoptosis in PC12 cells. This A(2A)-protective effect was blocked by protein kinase A (PKA) inhibitors and was not observed in a PKA-deficient PC12 variant. Stimulation of PKA also prevented apoptosis, suggesting that PKA is required for the protective effect of A(2A)-R. A general PKC inhibitor, but not down-regulation of conventional and novel PKCs, readily blocked the protective effect of A(2A)-R stimulation and PKA activation, suggesting that atypical PKCs (aPKCs) serve a critical role downstream of PKA. Consistent with this hypothesis, stimulation of A(2A)-R or PKA enhanced nuclear aPKC activity. In addition, the A(2A)-protective effect was blocked by a specific inhibitor of one aPKC, PKCzeta, whereas overexpression of a dominant-positive PKCzeta enhanced survival. In contrast, inhibitors of MAP kinase and phosphatidylinositol 3-kinase did not modulate the A(2A)-protective effect. Dominant-negative Akt also did not alter the A(2A)-protective effect, whereas it significantly reduced the protective action of nerve growth factor. Collectively, these data suggest that aPKCs can function downstream of PKA to mediate the A(2A)-R-promoted survival of PC12 cells. Furthermore, the results indicate that different extracellular stimuli can employ distinct signaling pathways to protect against apoptosis induced by the same insult.

Charge movements in intact amphibian skeletal muscle fibres in the presence of cardiac glycosides

1. Intramembrane charge movements were examined in intact voltage-clamped amphibian muscle fibres following treatment with cardiac glycosides in the hypertonic gluconate-containing solutions hitherto reported to emphasise the features of q(gamma) at the expense of q(beta) charge. 2. The application of chlormadinone acetate (CMA) at concentrations known selectively to block Na(+)-K(+)-ATPase conserved the steady-state voltage dependence of intramembrane charge, contributions from delayed (q(gamma)) charging transients, and their inactivation characteristics brought about by shifts in holding potential. 3. The addition of either ouabain (125, 250 or 500 nM) or digoxin (5 nM) at concentrations previously reported additionally to influence excitation-contraction coupling similarly conserved the steady-state charge-voltage relationships, Q(V), in fully polarised fibres to give values of maximum charge, Q(max), transition voltage, V*, and steepness factor, k, that were consistent with a persistent q component as reported on earlier occasions (Q(max) approximately = 25-27 nC F-1, V* approximately = -45 to -50 mV, k approximately = 7-9 mV). 4. In both cases shifts in holding potential from -90 to -50 mV produced a partial inactivation that separated steeply and more gradually voltage-dependent charge components in agreement with previous characterisations. 5. However, charge movements that were observed in the presence of either digoxin or ouabain were monotonic decays in which delayed (q(gamma)) transients could not be distinguished from the early charging records. These features persisted despite the further addition of chlormadinone acetate over a 10-fold concentration range (5-50 microM) known to displace ouabain from the Na(+)-K(+)-ATPase. 6. Ouabain (500 nM) restored the steady-state charge movement that was previously abolished by the addition of 2.0 mM tetracaine in common with previous results of using ryanodine receptor (RyR)-specific agents. 7. Perchlorate (8.0 mM) restored the delayed 'on' relaxations and increased the prominence of the 'off' decays produced by q(gamma) charge following treatment with cardiac glycosides. This was accompanied by a negative (approximately 10-15 mV) shift in the steady-state charge-voltage relationship but an otherwise conserved maximum charge, Q(max), and steepness factor, k, in parallel with previously reported effects of perchlorate following treatments with RyR-specific agents. 8. The features of cardiac glycoside action thus parallel those of other agents that act on RyR-Ca(2+) release channels yet influence the kinetics but spare the steady-state properties of intramembrane charge.

Immunohistochemical studies of Na+/I- symporter in human thyroid tissues--a correlation with clinical thyroid scintigraphy

BACKGROUND

Thyroid Na+/I- symporter (NIS) is thought to play an important role in iodide uptake in thyrocytes. We hypothesize that there is correlation between the expression of NIS protein in the normal and diseased thyroid tissues and their clinical thyroid scintigraphy.

METHODS

Twenty-seven patients, aged from 21 to 81, were studied from the surgical department of a tertiary referral center. Ten patients were with papillary carcinoma, 5 with follicular carcinoma, 5 with follicular adenoma, 5 with nodular goiter and 2 with Graves' disease. All the carcinoma patients underwent total thyroidectomy while others had lobectomy or subtotal thyroidectomy. The thyroid tissue sections prepared for study were stained with polyclonal hNIS antibody (SS Chiang, Ohio).

RESULTS

Most of the nodular goiters were negatively stained except 2 samples that showed weak signal focally. All cases with follicular adenoma or follicular carcinoma were negative for NIS expression, while some with papillary carcinoma were stained positive at sporadic follicles with weak signal. The thyroid tissue of Graves' disease was stained positive for NIS expression.

CONCLUSIONS

Thyroid tissues with hypofunctioning nodules displayed significantly reduced or undetectable level of NIS expression. It correlated well with pre-operative thyroid scans.

Rapid recovery of spontaneous baroreflex after sevoflurane anesthesia in ambulatory surgery

BACKGROUND

Although sevoflurane seems to have fulfilled the criteria of ideal anesthetic agent for ambulatory surgery, its effects on intraoperative alteration and postoperative recovery of arterial baroreflex have not been well documented. This study assessed the time required for patients anesthetized with sevoflurane to regain their baseline baroreflex after ambulatory surgeries.

METHODS

Ten ASA class I female patients scheduled for minor gynecological operation (D&C) were enrolled in this study. Spontaneous baroreflex sensitivity (SBR) calculated by sequence analysis of beat-to-beat variations in systolic arterial pressure and R-R intervals was recorded before anesthesia (Baseline), during anesthesia (Anesthesia), five min after operation (Post-op 1) and ten min after operation (Post-op 2). Data obtained from Anesthesia, Post-op 1, and Post-op 2 was compared with the Baseline.

RESULTS

SBR value determined in Baseline group (28.6 +/- 4.9 ms/mmHg) was significantly different from Anesthesia group (12.2 +/- 2.1 ms/mmHg) and Post-op 1 group (15.8 +/- 1.8 ms/mmHg). Patients regained their conscious baseline baroreflex sensitivity within ten min after sevoflurane was switched off.

CONCLUSIONS

Sevoflurane anesthesia depresses SBR and provides a quick SBR recovery upon emergence.

Legionnaires' disease in a patient with rheumatoid arthritis

A 62-year-old male with rheumatoid arthritis (RA) who was taking nonsteroid anti-inflammatory drug for controlling synovitis developed a flare of his arthritis, hepatitis, and pneumonia due to infection with Legionella pneumophila serotype 1. Adult respiratory distress syndrome (ARDS) occurred following the development of pneumonia. After the introduction of erythromycin and ventilator support with positive end expiratory pressure (PEEP), his condition stabilized and he recovered gradually. We suggest that L. pneumophila should be considered early in the differential diagnosis of pneumonia in RA patients due to their immunocompromised status.