Vaginal microbiomes show ethnic evolutionary dynamics and positive selection of Lactobacillus adhesins driven by a long-term niche-specific process

The vaginal microbiome's composition varies among ethnicities. However, the evolutionary landscape of the vaginal microbiome in the multi-ethnic context remains understudied. We perform a systematic evolutionary analysis of 351 vaginal microbiome samples from 35 multi-ethnic pregnant women, in addition to two validation cohorts, totaling 462 samples from 90 women. Microbiome alpha diversity and community state dynamics show strong ethnic signatures. Lactobacillaceae have a higher ratio of non-synonymous to synonymous polymorphism and lower nucleotide diversity than non-Lactobacillaceae in all ethnicities, with a large repertoire of positively selected genes, including the mucin-binding and cell wall anchor genes. These evolutionary dynamics are driven by the long-term evolutionary process unique to the human vaginal niche. Finally, we propose an evolutionary model reflecting the environmental niches of microbes. Our study reveals the extensive ethnic signatures in vaginal microbial ecology and evolution, highlighting the importance of studying the host-microbiome ecosystem from an evolutionary perspective.

The utility of intraoperative endoscopy to assist novice surgeons in the detection of gastric stenosis during laparoscopic sleeve gastrectomy

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is a commonly performed bariatric surgery. Gastric stenosis and leaks are 2 major complications associated with LSG and revision surgery might be needed. Herein, we report our experience of intraoperative endoscopy (IOE) to evaluate stenosis and leaks during LSG.

METHODS

LSG was performed by three surgeons. Patients who underwent LSG and IOE between January 2016 and March 2020 were enrolled and assigned to two groups: group 1 (1st-30th LSG case for each surgeon) and group 2 (> 30th LSG for each surgeon). Patients' anthropometric and biochemical data pre- and post-LSG, as well as IOE findings and follow-up esophagogastroduodenoscopy records were reviewed.

RESULTS

In total, 352 patients were enrolled including 90 patients in group 1 and 262 patients in group 2. Three out of 352 patients (0.9%) were found to have stenosis by IOE, which was related to tightly gastropexy stitch or reinforcement stitch, all of which were in group 1. Stenosis was resolved after removal of the stitch during LSG. The incidence of gastric stenosis detected by IOE was 3.3% (3/90) and 0% (0/262) in group 1 and group 2, respectively (P = 0.003). No leakage was found in this study and no patient developed clinical or endoscopic stenosis after LSG.

CONCLUSIONS

The existing evidence showed that IOE can help detect gastric stenosis during LSG, especially for novice surgeons, and the stenosis could be resolved during operation.

Nonlinear compression toward high-energy single-cycle pulses by cascaded focus and compression

The advancement of contemporary ultrafast science requires reliable sources to provide high-energy few-cycle light pulses. Through experiments and simulations, we demonstrate an arrangement of pulse postcompression, referred to as cascaded focus and compression (CASCADE), for generating millijoule-level, single-cycle pulses in a compact fashion. CASCADE is realized by a series of foci in matter, whereas pulse compression is provided immediately after each focus to maintain a high efficiency of spectral broadening. By implementing four stages of CASCADE in argon cells, we achieve 50-fold compression of millijoule-level pulses at 1030 nanometers from 157 to 3.1 femtoseconds, with an output pulse energy of 0.98 millijoules and a transmission efficiency of 73%. When driving high harmonic generation, these single-cycle pulses enable the creation of a carrier-envelope phase-dependent extreme ultraviolet continuum with energies extending up to 180 electron volts, providing isolated attosecond pulses at the output.

Statins Are Associated With Increased Insulin Resistance and Secretion

Objective

Statin treatment reduces the risk of atherosclerotic cardiovascular disease but is associated with a modest increased risk of type 2 diabetes, especially in those with insulin resistance or prediabetes. Our objective was to determine the physiological mechanism for the increased type 2 diabetes risk.

Approach and Results

We conducted an open-label clinical trial of atorvastatin 40 mg daily in adults without known atherosclerotic cardiovascular disease or type 2 diabetes at baseline. The co-primary outcomes were changes at 10 weeks versus baseline in insulin resistance as assessed by steady-state plasma glucose during the insulin suppression test and insulin secretion as assessed by insulin secretion rate area under the curve (ISRAUC) during the graded-glucose infusion test. Secondary outcomes included glucose and insulin, both fasting and during oral glucose tolerance test. Of 75 participants who enrolled, 71 completed the study (median age 61 years, 37% women, 65% non-Hispanic White, median body mass index, 27.8 kg/m2). Atorvastatin reduced LDL (low-density lipoprotein)-cholesterol (median decrease 53%, P<0.001) but did not change body weight. Compared with baseline, atorvastatin increased insulin resistance (steady-state plasma glucose) by a median of 8% (P=0.01) and insulin secretion (ISRAUC) by a median of 9% (P<0.001). There were small increases in oral glucose tolerance test glucoseAUC (median increase, 0.05%; P=0.03) and fasting insulin (median increase, 7%; P=0.01).

Conclusions

In individuals without type 2 diabetes, high-intensity atorvastatin for 10 weeks increases insulin resistance and insulin secretion. Over time, the risk of new-onset diabetes with statin use may increase in individuals who become more insulin resistant but are unable to maintain compensatory increases in insulin secretion.

Oct4 promotes M2 macrophage polarization through upregulation of macrophage colony-stimulating factor in lung cancer

Background

Expression of Oct4 maintains cancer stem cell (CSC)-like properties in lung cancer cells and is correlated with poor prognosis of lung adenocarcinoma. M2-type tumor-associated macrophages (TAMs) promote cancer cell migration and metastasis. Tumor microenvironments promote monocyte differentiation into M2 TAMs via a complex cytokine-based connection. We explored the role of Oct4 in cytokine secretion in lung cancer and its impact on M2 TAM polarization.

Methods

Monocytes co-cultured with the conditioned medium from Oct4-overexpressing lung cancer cells were used to investigate M2 TAM differentiation. The inflammatory factors in the conditioned medium of Oct4-overexpressing A549 cells were examined using human inflammation antibody arrays. The correlations of Oct4, macrophage colony-stimulating factor (M-CSF), and M2 TAMs were validated in lung cancer cells, syngeneic mouse lung tumor models, and clinical samples of non-small cell lung cancer (NSCLC).

Results

Oct4-overexpressing A549 cells expressed elevated levels of M-CSF, which contributed to increased M2 macrophages and enhanced tumor migration. Overexpression of Oct4 enhanced tumor growth and reduced the survival of lung tumor-bearing mice, which was correlated with increased number of M2 macrophages in lung cancer. Notably, NSCLC patients with high expression levels of Oct4, M-CSF, and M2 TAMs had the poorest recurrence-free survival. A positive correlation between Oct4, M-CSF, and M2 TAMs was observed in the tumor tissue of NSCLC patient. Treatment with all-trans retinoic acid exerted anti-tumor effects and reduced M2 TAMs in tumor-bearing mice.

Conclusions

Our results indicate that Oct4 expressed by lung cancer cells promotes M2 macrophage polarization through upregulation of M-CSF secretion, leading to cancer growth and metastasis. Our findings also implicate that the Oct4/M-CSF axis in M2 macrophage polarization may be potential therapeutic targets for lung cancer.

Molecular Choreography of Acute Exercise

Acute physical activity leads to several changes in metabolic, cardiovascular, and immune pathways. Although studies have examined selected changes in these pathways, the system-wide molecular response to an acute bout of exercise has not been fully characterized. We performed longitudinal multi-omic profiling of plasma and peripheral blood mononuclear cells including metabolome, lipidome, immunome, proteome, and transcriptome from 36 well-characterized volunteers, before and after a controlled bout of symptom-limited exercise. Time-series analysis revealed thousands of molecular changes and an orchestrated choreography of biological processes involving energy metabolism, oxidative stress, inflammation, tissue repair, and growth factor response, as well as regulatory pathways. Most of these processes were dampened and some were reversed in insulin-resistant participants. Finally, we discovered biological pathways involved in cardiopulmonary exercise response and developed prediction models revealing potential resting blood-based biomarkers of peak oxygen consumption.

Nerve growth factor induced farnesoid X receptor upregulation modulates autophagy flux and protects hepatocytes in cholestatic livers

Upregulation of nerve growth factor (NGF) in parenchymal hepatocytes has been shown to exert hepatoprotective function during cholestatic liver injury. However, the modulatory role of NGF in regulation of liver autophagy remains unclear. This study aimed to scrutinize the regulatory role of NGF in hepatic expression of farnesoid X receptor (FXR), a bile acid (BA)-activated nuclear receptor, and to determine its cytoprotective effect on BA-induced autophagy and cytotoxicity. Livers of human hepatolithiasis and bile duct ligation (BDL)-induced mouse cholestasis were used for histopathological and molecular detection. The regulatory roles of NGF in autophagy flux and FXR expression, as well as its hepatoprotection against BA cytotoxicity were examined in cultured hepatocytes. FXR downregulation in human hepatolithiasis livers showed positive correlation with hepatic NGF levels. NGF administration upregulated hepatic FXR levels, while neutralization of NGF decreased FXR expression in BDL-induced cholestatic mouse livers. In vitro studies demonstrated that NGF upregulated FXR expression, increased cellular LC3 levels, and exerted hepatoprotective effect in cultured primary rat hepatocytes. Conversely, autophagy inhibition abrogated NGF-driven cytoprotection under BA exposure, suggesting involvement of NGF-modulated auophagy flux. Although FXR agonistic GW4064 stimulation did not affect auophagic LC3 levels, FXR activity inhibition significantly potentiated BA-induced cytotoxicity and increased cellular p62/SQSTM1 and Rab7 protein in SK-Hep1 hepatocytes. Moreover, FXR gene silencing abolished the protective effect of NGF under BA exposure. These findings support that NGF modulates autophagy flux via FXR upregulation and protects hepatocytes against BA-induced cytotoxicity. NGF/FXR axis is a novel therapeutic target for treatment of cholestatic liver diseases.

A Higher Preoperative Glycemic Profile Is Associated with Rapid Gastric Emptying After Sleeve Gastrectomy for Obese Subjects

BACKGROUND

Recent reports have shown that sleeve gastrectomy (SG) accelerates gastric emptying (GE), but the etiology remains unclear. This study aimed to investigate the factors affecting GE before and after SG.

METHODS

We enrolled 35 normal weight healthy subjects and 23 obese patients receiving SG. The normal individuals and obese patients before and 3 months after SG received oatmeal-based scintigraphy to measure GE. Gastrointestinal symptoms and circulating levels of peptide YY (PYY) were also measured.

RESULTS

There were no differences in the GE parameters, including simple half-time at 3 h and percentage of gastric retention at 0.5, 1, 2, and 3 h between healthy controls and pre-SG obese subjects. SG led to accelerated GE, more gastrointestinal symptoms, and increased fasting PYY levels postoperatively. Based on our previously established normal GE values, 18 (78.3%) obese patients with rapid postoperative GE had higher levels of preoperative fasting glucose and glycated hemoglobin, and homeostasis model assessment of the insulin resistance index than those with normal postoperative GE. Twelve (52.2%) obese patients had preoperative diabetes mellitus (DM), and only four (17.4%) remained diabetic after SG. The post-SG gastric retention at 0.5 and 1 h was lower in patients with preoperative DM than in those without preoperative DM. Neither severity of gastrointestinal symptoms nor fasting PYY levels were associated with postoperative GE alterations.

CONCLUSION

Most of the obese patients had accelerated GE after SG. A higher preoperative glycemic profile was associated with rapid post-SG GE.

Traversal of the Blood-Brain Barrier by Cleavable l-Lysine Conjugates of Apigenin

Apigenin, a flavone abundant in parsley and celery, is known to act on several CNS receptors, but its very poor water solubility (<0.001 mg/mL) impedes its absorption in vivo and prevents clinical use. Herein, apigenin was directly conjugated with glycine, l-phenylalanine, and l-lysine to give the corresponding carbamate derivatives, all of which were much more soluble than apigenin itself (0.017, 0.018, and 0.13 mg/mL, respectively). The Lys-apigenin carbamate 10 had a temporary sedative effect on the mice within 5 min of intraperitoneal administration (single dose of 0.4 mg/g) and could be detected in the mice brain tissues at a concentration of 0.82 μg/g of intact Lys-apigenin carbamate 10 and 0.42 ug/g of apigenin at 1.5 h. This study accomplished the delivery of apigenin across the BBB in a manner that might be applicable to other congeners, which should inform the future development of BBB-crossing flavonoids.

Treatment efficiency and stability of skeletal Class III malocclusion with a surgery-first approach

OBJECTIVES

To compare treatment duration in skeletal Class III malocclusion patients managed with a 2-step treatment (surgery-first approach, SFA) and conventional 3-step treatment, and to compare stability of surgical outcomes between segmentation and non-segmentation in the 2-step treatment group.

SETTING AND SAMPLE POPULATION

The sample population consisted of 37 patients who completed orthognathic surgery (OGS) and orthodontic correction at the Charm Aesthetic Surgery Clinic (Taipei, Taiwan) between 2012 and 2015. Of these, 26 received 2-step treatment and 11 received 3-step treatment.

MATERIALS AND METHODS

To compare treatment efficiency and stability, three time points were analysed: T₀ , before treatment (before OGS in the 2-step group and before orthodontic treatment in the 3-step group); T₁ , after OGS but before orthodontic correction (cone beam computed tomography (CBCT) was obtained within 2 weeks of OGS); and T₂ , after orthodontic correction (CBCT was obtained on the day of bracket removal). The post-OGS (T₁ ) CBCT items were individually superimposed on the pre-treatment (T₀ ) CBCT items to determine the distance of B point migration.

RESULTS

A significant difference was found in treatment times between 2-step treatment and conventional 3-step treatment. In addition, no significant difference was found when comparing B-X (mm) and B-Y (mm) at T₂ -T₁ for the segmentation and non-segmentation groups.

CONCLUSIONS

Using SFA for skeletal Class III malocclusions saves approximately 6 months of treatment time over 3-step treatment; the stability of the segmentation group was comparable to that of the non-segmentation group, a result that is possibly associated with the fixation of 2 miniplates.

Gastrectomy is Associated with an Increased Risk of Pyogenic Liver Abscess: A 13-Year Nationwide Cohort Study

Whether patients who have undergone gastrectomy are at a high risk of developing pyogenic liver abscess (PLA) remains debatable. From the inpatient claims records of Taiwan’s National Health Insurance Research Database, we identified 33 834 patients with a history of 2000–2010 and135 336 controls without a history of gastrectomy. The 2cohorts were matched by age, sex, and admission year and followed-up until the end of 2011 for estimating the risk of PLA. Overall, the incidence of PLA was 3.5-fold higher in the gastrectomy cohort than in the control cohort (21.6 vs 5.76 per 10 000 person-y). The adjusted hazard ratio (aHR) for the gastrectomy cohort obtained using the multivariate Cox proportional hazards regression model was 3.08 (95% confidence interval [CI] = 2.60–3.64). An elevated post gastrectomy PLA risk was observed in both men and women. Age-specific data revealed that the aHR for the gastrectomy cohort, compared with the control cohort, was the highest in patients younger than 50 years (aHR = 5.16, 95% CI = 2.96–9.01). An addition analysis showed that the gastrectomy cohort exhibited an elevated PLA risk regardless of whether the patients underwent total or partial gastrectomy. Patients with a history of gastrectomy exhibit a high risk of PLA.

Upregulation of Haploinsufficient Gene Expression in the Brain by Targeting a Long Non-coding RNA Improves Seizure Phenotype in a Model of Dravet Syndrome

Dravet syndrome is a devastating genetic brain disorder caused by heterozygous loss-of-function mutation in the voltage-gated sodium channel gene SCN1A. There are currently no treatments, but the upregulation of SCN1A healthy allele represents an appealing therapeutic strategy. In this study we identified a novel, evolutionary conserved mechanism controlling the expression of SCN1A that is mediated by an antisense non-coding RNA (SCN1ANAT). Using oligonucleotide-based compounds (AntagoNATs) targeting SCN1ANAT we were able to induce specific upregulation of SCN1A both in vitro and in vivo, in the brain of Dravet knock-in mouse model and a non-human primate. AntagoNAT-mediated upregulation of Scn1a in postnatal Dravet mice led to significant improvements in seizure phenotype and excitability of hippocampal interneurons. These results further elucidate the pathophysiology of Dravet syndrome and outline a possible new approach for the treatment of this and other genetic disorders with similar etiology.

Methylprednisolone Protects Cardiac Pumping Mechanics from Deteriorating in Lipopolysaccharide-Treated Rats

It has been shown that a prolonged low-dose corticosteroid treatment attenuates the severity of inflammation and the intensity and duration of organ system failure. In the present study, we determined whether low-dose methylprednisolone (a synthetic glucocorticoid) can protect male Wistar rats against cardiac pumping defects caused by lipopolysaccharide-induced chronic inflammation. For the induction of chronic inflammation, a slow-release ALZET osmotic pump was subcutaneously implanted to infuse lipopolysaccharide (1 mg kg(-1) d(-1)) for 2 weeks. The lipopolysaccharide-challenged rats were treated on a daily basis with intraperitoneal injection of methylprednisolone (5 mg kg(-1) d(-1)) for 2 weeks. Under conditions of anesthesia and open chest, we recorded left ventricular (LV) pressure and ascending aortic flow signals to calculate the maximal systolic elastance (E max) and the theoretical maximum flow (Q max), using the elastance-resistance model. Physically, E max reflects the contractility of the myocardium as an intact heart, whereas Q max has an inverse relationship with the LV internal resistance. Compared with the sham rats, the cardiodynamic condition was characterized by a decline in E max associated with the increased Q max in the lipopolysaccharide-treated rats. Methylprednisolone therapy increased E max, which suggests that the drug may have protected the contractile status from deteriorating in the inflamed heart. By contrast, methylprednisolone therapy considerably reduced Q max, indicating that the drug may have normalized the LV internal resistance. In parallel, the benefits of methylprednisolone on the LV systolic pumping mechanics were associated with the reduced cardiac levels of negative inotropic molecules such as peroxynitrite, malondialdehyde, and high-mobility group box 1 protein. Based on these data, we suggested that low-dose methylprednisolone might prevent lipopolysaccharide-induced decline in cardiac intrinsic contractility and LV internal resistance, possibly through its ability to reduce the aforementioned myocardial depressant substances. However, since our results were obtained in anesthetized open-chest rats, extrapolation to what may occur in conscious intact animals should be done with caution.

Proper BMP Signaling Levels Are Essential for 3D Assembly of Hepatic Cords from Hepatoblasts and Mesenchymal Cells

BACKGROUND

Because the molecular mechanisms of morphogenesis of the hepatic cord and sinus are unclear, we investigated the involvement of bone morphogenetic protein (BMP4) in hepatic sinusoid morphogenesis.

METHODS

We used embryonic chicken livers, which develop rapidly, as our model, and investigated expression of BMP-related genes. BMP4 activity was manipulated by overexpressing BMP4 and its antagonist, noggin.

RESULTS

During hepatic cord morphogenesis, BMP4 and its receptors are expressed in both peri-sinusoidal cells and hepatoblasts as the sinusoids form, whereas noggin is expressed transiently in peri-sinusoidal cells at early stages. Suppression of BMP activity with noggin overexpression disrupted normal hepatic sinusoid structure, leading to liver congestion, failure of fibronectin deposition, and markedly reduced numbers of peri-sinusoidal cells. However, overexpression of BMP did not change sinusoidal morphology but increased endothelial cell number. Noggin overexpression resulted in disrupted cord organization, and dilated sinusoidal space, eventually leading to increased apoptosis and failed hepatocyte differentiation.

CONCLUSIONS

Our results show that proper BMP signaling mediates peri-sinusoidal cell-hepatoblast interactions during development; this is essential for hepatic cord organization among hepatoblasts, endothelium, and presumptive hepatic stellate cells.

Dopamine impairs functional integrity of rat hepatocytes through nuclear factor kappa B activity modulation: An in vivo, ex vivo, and in vitro study

Dopamine (DA) is commonly used to maintain the hemodynamic stability of brain-dead donors despite its controversial effects on organ functions. This study aimed at examining the hemodynamic effect of DA in a rat brain-dead model in vivo, alteration of hepatocyte integrity in liver grafts after ex vivo preservation, and changes in cultured clone-9 hepatocytes including cellular viability, cell cycle, apoptotic regulators, and lipopolysaccharide (LPS)-stimulated nuclear factor kappa B (NF-κB) signaling machinery. Although in vivo findings demonstrated enhanced portal venous blood flow and hepatic microcirculatory perfusion after DA infusion, no apparent advantage was noted in preserving hepatocyte integrity ex vivo. In vitro, prolonged exposure to high-dose DA reduced proliferation and induced G1 growth arrest of clone-9 hepatocytes with concomitant decreases in B cell lymphoma 2 (BCL2)/B cell lymphoma 2-associated X protein (BAX) and heat shock protein 70/BAX protein ratios and intracellular NF-κB p65. Moreover, DA pretreatment suppressed LPS-elicited inhibitor of κBα phosphorylation and subsequent NF-κB nuclear translocation, suggesting that DA may down-regulate NF-κB signaling, thereby reducing expression of antiapoptotic regulators, such as BCL2. In conclusion, despite augmentation of hepatic perfusion, DA infusion failed to preserve hepatocyte integrity both in vivo and ex vivo. In vitro findings demonstrated that high-dose DA may hamper the function of NF-κB signaling machinery and eventually undermine functional integrity of hepatocytes in liver grafts.

Increased Risk of Pyogenic Liver Abscess Among Patients With Colonic Diverticular Diseases: A Nationwide Cohort Study

Whether patients with diverticular diseases exhibit a higher risk of developing pyogenic liver abscess (PLA) remains inconclusive.From the inpatient claims in Taiwan's National Health Insurance Research Database, we identified 54,147 patients diagnosed with diverticulosis in the 1998 to 2010 period and 216,588 controls without the disorder. The 2 cohorts were matched by age, sex, and admission year, and were followed up until the end of 2010 to estimate the risk of PLA.Overall, the incidence of PLA was 2.44-fold higher in the diverticular-disease group than in the controls (11.5 vs 4.65 per 10,000 person-year). The adjusted hazard ratio (aHR) of PLA was 2.11 (95% confidence interval [CI], 1.81-2.44) for the diverticular-disease group, according to a multivariate Cox proportional hazards regression model. The age-specific data showed that the aHR for the diverticular-disease group, compared with the controls, was the highest inpatients younger than 50 years old (aHR, 4.03; 95% CI, 2.77-5.85). Further analysis showed that the diverticular-disease group exhibited an elevated risk of PLA regardless of whether patients had diverticulitis.The patients with diverticular diseases exhibited a higher risk of PLA.

Preexisting Diabetes and Risks of Morbidity and Mortality After Gastrectomy for Gastric Cancer: A Nationwide Database Study

The purpose of this study was to determine the risk of surgical mortality and morbidity in patients with diabetes mellitus (DM) undergoing a gastrectomy for gastric cancer (GC). Using the Taiwan National Health Insurance Research Database, we identified 6284 patients who underwent gastrectomy for GC from 1999 to 2010. In addition, we created a non-DM control cohort consisting of 6268 patients who received gastrectomy during the same period. Compared with the non-DM cohort, the DM cohort exhibited a higher prevalence of preoperative coexisting medical conditions, namely hypertension, hyperlipidemia, coronary artery disease, chronic kidney disease, chronic pulmonary disease, stroke, and cirrhosis. The odds ratio (OR) of 30-day postoperative mortality after gastrectomy in the DM cohort was 1.04 (95% confidence interval 0.78-1.40) after we adjusted for covariates. The DM cohort did not exhibit a significantly higher risk of 30-day postoperative morbidities. Further analysis revealed that only patients with a history of a DM-related coma exhibited a higher risk of 30-day postoperative mortality (adjusted OR 2.46, 95% confidence interval 1.10 - 5.54). Moreover, the risk of 90-day postoperative mortality was significantly higher in patients with DM-related eye involvement, coma, peripheral circulatory disease, and renal manifestations, in comparison with the non-DM cohort. The risk of 90-day mortality after gastrectomy for GC is higher in patients with DM-related manifestations than those without DM.

Long-term risk of pancreatitis and diabetes after cholecystectomy in patients with cholelithiasis but no pancreatitis history: a 13-year follow-up study

BACKGROUND & AIM

Patients with biliary pancreatitis are suggested to undergo cholecystectomy to prevent the recurrence of pancreatitis. However, it remains controversial whether cholecystectomy is associated with reduced risks of pancreatitis and diabetes in patients with cholelithiasis and no history of pancreatitis.

METHODS

From Taiwan's National Health Insurance Research Database, we identified the following cohorts and analyzed the long-term risks of pancreatitis and diabetes in each cohort: 1) cholecystectomy cohort: cholelithiasis patients who had no history of pancreatitis and diabetes and underwent cholecystectomy; and 2) comparison cohort: cholelithiasis patients who had no history of pancreatitis and diabetes and did not undergo cholecystectomy.

RESULTS

The cholecystectomy group and the comparison group had similar distributions of age, sex, and comorbidities, except for hyperlipidemia. The proportion of patients in the cholecystectomy group who underwent endoscopic cholangiographic procedures was higher than that in the comparison group. Cholecystectomy was associated with a reduced risk of pancreatitis (adjusted hazard ratio [HR], 0.49; 95% confidence interval [CI], 0.36-0.68). Age-specific analyses showed that pancreatitis risk was decreased in patients younger than 50 and older than 65years. Both men and women exhibited reduced risks of pancreatitis after cholecystectomy. However, cholecystectomy was not associated with changes in the risk for diabetes.

CONCLUSION

Cholecystectomy for cholelithiasis is associated with a reduced risk of pancreatitis, but not of diabetes, in patients without previous history of pancreatitis and diabetes.

Pre-existing diabetes and risks of morbidity and mortality after liver transplantation: A nationwide database study in an Asian population

BACKGROUND

Whether diabetes mellitus (DM) is associated with a higher risk of perioperative mortality and mortality after liver transplantation (LTx) remains unclear.

METHODS

We compared the risk of postoperative mortality and morbidity in DM and non-DM patients undergoing LTx. We enrolled 558 DM patients who underwent LTx from 2000 to 2010.

RESULTS

DM was associated with elevated 90-day risk of post-LTx stroke. Otherwise, the DM cohort did not exhibit significantly higher risks of postoperative morbidities, such as septicemia, pneumonia, and wound infection, than the non-DM cohort. Cox proportional hazards regression model showed that patients with DM with coexisting renal manifestations were at a significantly high risk of 30-day and 90-day postoperative mortality. Further comorbidity stratification analysis showed that DM cohort exhibited higher risk of mortality than the non-DM cohort if the patients had liver cancer, or did not have hypertension, ischemic heart disease, and chronic obstructive pulmonary disease.

CONCLUSION

DM is associated with elevated risk of 90-day post-LTx. Moreover, DM patients with coexisting renal manifestations exhibited an increased postoperative risk of mortality after LTx.

Long-term risk of acute coronary syndrome in splenectomized patients due to splenic injury

We aimed to assess the magnitude and duration of risk of acute coronary syndrome (ACS) associated with splenectomy for splenic injury.We identified 5139 splenectomized patients (the splenectomy cohort) to compare with 2 other cohorts for assessing the magnitude and risk of ACS: the first cohort comprising subjects without splenic injury and without splenectomy (control cohort), and the second cohort comprising nonsplenectomized patients with splenic injury (nonsplenectomy cohort; n = 6391). For each splenic injury patient (n = 11530), 4 control comparisons were frequency-matched by the year of index date, age, and sex (n = 46120).The adjusted risk of ACS was significantly higher in the splenectomy group than in the control group (2.08 vs 1.68 per 1000 person-years; adjusted hazard ratio [HR], 1.30; 95% confidence interval [CI], 1.01-1.68). The sex-specific data showed that the adjusted HR for the splenectomy group, compared with the control group, was 1.29 in men (95% CI, 0.97-1.73) and 1.36 in women (95% CI, 0.79-2.33). The age-specific analyses failed to demonstrate a significantly higher adjusted HR of ACS in the splenectomized patients in any age subgroup, compared with their counterparts in the control group. Furthermore, no difference in the risk of ACS was detected between the splenectomy and nonsplenectomy cohorts within the splenic injury patients.In comparison with the control cohort, patients undergoing splenectomy for splenic injury exhibited an elevated risk of ACS.

Up-regulation of nerve growth factor in cholestatic livers and its hepatoprotective role against oxidative stress

The role of nerve growth factor (NGF) in liver injury induced by bile duct ligation (BDL) remains elusive. This study aimed to investigate the relationship between inflammation and hepatic NGF expression, to explore the possible upstream molecules up-regulating NGF, and to determine whether NGF could protect hepatocytes from oxidative liver injury. Biochemical and molecular detection showed that NGF was up-regulated in cholestatic livers and plasma, and well correlated with systemic and hepatic inflammation. Conversely, systemic immunosuppression reduced serum NGF levels and resulted in higher mortality in BDL-treated mice. Immunohistochemistry showed that the up-regulated NGF was mainly localized in parenchymal hepatocytes. In vitro mechanistic study further demonstrated that TGF-β1 up-regulated NGF expression in clone-9 and primary rat hepatocytes. Exogenous NGF supplementation and endogenous NGF overexpression effectively protected hepatocytes against TGF-β1- and oxidative stress-induced cell death in vitro, along with reduced formation of oxidative adducted proteins modified by 4-HNE and 8-OHdG. TUNEL staining confirmed the involvement of anti-apoptosis in the NGF-exhibited hepatoprotection. Moreover, NGF potently induced Akt phosphorylation and increased Bcl-2 to Bax ratios, whereas these molecular alterations by NGF were only seen in the H₂O₂-, but not TGF-β1-treated hepatocytes. In conclusion, NGF exhibits anti-oxidative and hepatoprotective effects and is suggested to be therapeutically applicable in treating cholestatic liver diseases.

Type II diabetes mellitus is associated with a reduced risk of cholangiocarcinoma in patients with biliary tract diseases

It has not yet been reported whether Type II diabetes mellitus (DM) is associated with an increased cholangiocarcinoma (CC) risk in patients with biliary tract diseases. We identified 123,050 patients concomitantly diagnosed with biliary tract diseases and DM between 1998 and 2010. The control cohort consisted of 122,721 individuals with biliary tract diseases but not DM. Both cohorts were followed-up until the end of 2010 to estimate the risk of CC. We also compared the risk of CC between DM and non-DM cohorts without biliary tract diseases. Overall, the incidence of CC was 21% lower among the DM patients than among the control patients (1.11 vs. 1.41 per 1,000 person-years). DM cohorts exhibited significantly reduced risks for both intrahepatic and extrahepatic CC. A multivariable Cox proportional hazards regression model was used, and the adjusted hazard ratio (HR) of CC was 0.74 (95% confidence interval [CI], 0.66-0.82) for the DM cohort in comparison with the control cohort. The age-specific data indicated that compared with the control patients, the adjusted HRs for the DM patients were significantly lower among patients 50-64 (adjusted HR = 0.67; 95% CI = 0.55-0.82) and 65-74 years old (adjusted HR = 0.70; 95% CI, 0.59-0.84). Furthermore, DM was associated with a lower risk of CC among patients with biliary diseases, regardless of the presence of comorbidities and the status of cholecystectomy. In the patients without biliary tract diseases, DM is associated with significantly increased risk of CC (adjusted HR = 1.58; 95% CI, 1.37-1.82).

Hospitalization for Inflammatory Bowel Disease is Associated with Increased Risk of Breast Cancer: A Nationwide Cohort Study of an Asian Population

PURPOSE

To learn whether women with inflammatory bowel disease (IBD) exhibit a higher risk of breast cancer.

METHODS

We identified 4,856 women with IBD symptoms from 1998 to 2008 and 19,424 control patients without the disorder, frequency matched by age, sex, and admission year. Both cohorts were followed-up until the end of 2010 to estimate the risk of breast cancer.

RESULTS

Overall, the incidence of breast cancer was similar in the IBD and control cohorts (1.31 vs. 1.25 per 1,000 person-years). The adjusted hazard ratio of breast cancer was 0.95 (95 % confidence interval 0.66-1.36) for the IBD patients. Further analysis revealed that neither Crohn disease nor ulcerative colitis was associated with the risk of developing breast cancer in women. The age-specific analysis indicated that the incidence of breast cancer was highest in the 45- to 65-year-old age group in both cohorts. The incidence of breast cancer was significantly increased in patients who required hospitalization twice or more per year, compared with the control cohort (adjusted hazard ratio 8.45; 95 % confidence interval 4.64-15.4). Moreover, age-specific analysis showed that patients aged less than 65 years old (≤44 or 45-65 years of age) exhibited a strong association between IBD hospitalization and breast cancer risk.

CONCLUSIONS

The risk of breast cancer was positively proportional to the frequency of admission for IBD. Therefore, careful surveillance of breast cancer should be sought for female IBD patients with 2 or more annual hospitalizations.

Long-term risk of mesenteric ischemia in patients with inflammatory bowel disease: a 13-year nationwide cohort study in an Asian population

BACKGROUND

It is unclear whether patients with inflammatory bowel disease (IBD) have higher risks of developing mesenteric ischemia.

METHODS

We enrolled 9,363 patients who had been hospitalized because of IBD between January 1998 and December 2010, along with 37,452 control patients who were matched at a 1:4 proportion for age, sex, and index year. We accounted the cumulative incidences and hazard ratios (HRs) of developing mesenteric ischemia during the 13-year study period.

RESULTS

Patients with IBD had a considerably higher incidence rate of subsequent mesenteric ischemia compared with the controls (22.7 vs 3.09 per 10,000 person-years), with adjusted HR of 6.33 (95% confidence interval: 4.75 to 8.43). A multivariate stratified analysis showed that the mesenteric ischemia risk after adjustment for comorbidities is significantly higher in patients of all age groups, particularly in patients younger than 44 years (adjusted HR: 48.0; 95% confidence interval: 11.3 to 203.9). Moreover, patients with IBD were at highest risk of developing mesenteric ischemia within the first year of follow-up.

CONCLUSIONS

Careful follow-up and effective therapy are necessary to reduce the excessive risk in these patients.

Pyridoxamine protects against mechanical defects in cardiac ageing in rats: studies on load dependence of myocardial relaxation

New Findings

Our team demonstrated in the past that pyridoxamine attenuated arterial stiffening by targeting the pathogenic formation of glycated collagen cross-links in aged rats. Herein, we examined whether pyridoxamine therapy can protect against mechanical defects in myocardial relaxation by improving arterial wave properties and cardiac contractile performance in senescent animals. Fifteen-month-old male Fisher 344 rats were treated daily with pyridoxamine (1 g l⁻¹ in drinking water) for 5 months and compared with age-matched untreated control animals (20 months old). Arterial wave properties were characterized by wave transit time (τ_w) and wave reflection factor (R_f). We measured the contractile status of the myocardium in an intact heart as the left ventricular (LV) end-systolic elastance (E_es). Myocardial relaxation was described according to the time constant of the LV isovolumic pressure decay (τ_e). Pyridoxamine therapy prevented the age-associated prolongation in LV τ_e and the diminished E_es in senescent rats. The drug also attenuated the age-related augmentation in afterload imposed on the heart, as evidenced by the increased τ_w and decreased R_f. We found that the LV τ_e was significantly influenced by both the arterial τ_w and R_f (τ_e = 16.3902 + 8.3123 × R_f − 0.4739 × τ_w; r = 0.7048, P < 0.005). In the meantime, the LV τ_e and the LV E_es showed a significant inverse linear correlation (τ_e = 13.9807 − 0.0068 × E_es; r = 0.6451, P < 0.0005). All these findings suggested that long-term treatment with pyridoxamine might ameliorate myocardial relaxation rate, at least partly through its ability to enhance myocardial contractile performance, increase wave transit time and decrease wave reflection factor in aged rats.

Involvement of the nuclear high mobility group B1 peptides released from injured hepatocytes in murine hepatic fibrogenesis

This study investigated the pro-fibrogenic role of high mobility group box 1 (HMGB1) peptides in liver fibrogenesis. An animal model of carbon tetrachloride (CCl4)-induced liver fibrosis was used to examine the serum HMGB1 levels and its intrahepatic distribution. The increased serum HMGB1 levels were positively correlated with elevation of transforming growth factor-β1 (TGF-β1) and collagen deposition during fibrogenesis. The cytoplasmic distribution of HMGB1 was noted in the parenchymal hepatocytes of fibrotic livers. In vitro studies confirmed that exposure to hydrogen peroxide and CCl4 induced an intracellular mobilization and extracellular release of nuclear HMGB1 peptides in clone-9 and primary hepatocytes, respectively. An uptake of exogenous HMGB1 by hepatic stellate cells (HSCs) T6 cells indicated a possible paracrine action of hepatocytes on HSCs. Moreover, HMGB1 dose-dependently stimulated HSC proliferation, up-regulated de novo synthesis of collagen type I and α-smooth muscle actin (α-SMA), and triggered Smad2 phosphorylation and its nuclear translocation through a TGF-β1-independent mechanism. Blockade with neutralizing antibodies and gene silencing demonstrated the involvement of the receptor for advanced glycation end-products (RAGE), but not toll-like receptor 4, in cellular uptake of HMGB1 and the HMGB1-mediated Smad2 and ERK1/2 phosphorylation as well as α-SMA up-regulation in HSC-T6 cells. Furthermore, anti-RAGE treatment significantly ameliorated CCl4-induced liver fibrosis. In conclusion, the nuclear HMGB1 peptides released from parenchymal hepatocytes during liver injuries may directly activate HSCs through stimulating HSC proliferation and transformation, eventually leading to the fibrotic changes of livers. Blockade of HMGB1/RAGE signaling cascade may constitute a therapeutic strategy for treatment of liver fibrosis.

Long-term risk of acute coronary syndrome in patients with cholangitis: a 13-year nationwide cohort study

BACKGROUND & AIMS

Patients with cholangitis may exhibit repeated and chronic inflammation of the biliary tract despite successful medical or surgical treatments. This nationwide cohort study examined the association between cholangitis and the subsequent development of acute coronary syndrome (ACS).

METHODS

We identified a cohort of 37676 patients who were diagnosed with cholangitis between January 1998 and December 2010, and a comparison cohort of 150704 subjects frequency matched by age, sex, and index year after excluding comorbidities for ACS. Both cohorts were followed until the end of 2010 to measure the incidence of ACS. Both incidence rate ratios and hazard ratios of ACS were estimated by age and sex.

RESULTS

Sex-specific analysis showed that males were at a higher incidence of ACS than females in both groups with (16.2 vs 11.5 per 10,000 person-years) and without (18.7 vs 12.5 per 10,000 person-years) cholangitis. The incidence of ACS also increased with age no matter having or not having cholangitis. The age stratified analysis revealed that the risk of ACS was significantly higher in patients with cholangitis younger than 65 years old. The multivariable Cox proportional hazard model demonstrated that cholangitis was significantly associated with ACS (adjusted hazard ratio [HR]=1.18; 95% confidence interval [CI], 1.03-1.35) after adjusting age and sex in the model.

CONCLUSIONS

This study suggests that patients with cholangitis are at an elevated risk of ACS. Awareness of the potential ACS risk for patients with cholangitis is important for patients and clinicians.

Diabetes mellitus and increased postoperative risk of acute renal failure after hepatectomy for hepatocellular carcinoma: a nationwide population-based study

BACKGROUND

This study aimed to determine the effects of diabetes mellitus (DM) on the risk of surgical mortality and morbidity in patients undergoing hepatectomy for hepatocellular carcinoma (HCC).

METHODS

We identified 2,962 DM patients who underwent a hepatectomy for HCC from 2000 to 2010. The non-DM control cohort consisted of 2,962 patients who also received a hepatectomy during the same period. Age, sex, comorbidities, and year of admission were all matched between the 2 cohorts.

RESULTS

The prevalence of preoperative coexisting medical conditions was comparable between the DM and non-DM cohorts, except the percentage of patients undergoing major hepatectomy (lobectomy; 18.1 % in the DM cohort vs. 20.4 % in the non-DM cohort; p = 0.02).The hazard ratio (HR) of 30-day postoperative mortality in the DM patients after hepatectomy was 1.17 [95 % confidence interval (CI) 0.75-1.84] after adjustment. The DM cohort exhibited a significantly higher risk of postoperative septicemia (adjusted hazard ratio, 1.45; 95 % CI 1.06-2.00) and acute renal failure (adjusted hazard ratio, 1.70; 95 % CI 1.01-2.84) compared with that of the non-DM cohort, but this higher risk was not associated with the increased risk of other major morbidities, including pneumonia, stroke, and myocardial infarction. Further analysis showed that major hepatectomy (lobectomy) in DM patients carried higher risks of septicemia and acute renal failure. In multiple regression models, preoperative diabetes-related comorbidities were not significantly associated with 30-day postoperative mortality.

CONCLUSIONS

DM is associated with a significantly high risk of septicemia and acute renal failure, but not with other major complications or mortality, after hepatectomy for HCC.

Methylprednisolone stiffens aortas in lipopolysaccharide-induced chronic inflammation in rats

Introduction

Glucocorticoids are commonly used as therapeutic agents in many acute and chronic inflammatory and auto-immune diseases. The current study investigated the effects of methylprednisolone (a synthetic glucocorticoid) on aortic distensibility and vascular resistance in lipopolysaccharide-induced chronic inflammation in male Wistar rats.

Methods

Chronic inflammation was induced by implanting a subcutaneous slow-release ALZET osmotic pump (1 mg kg⁻¹ day⁻¹ lipopolysaccharide) for either 2 or 4 weeks. Arterial wave transit time (τ) was derived to describe the elastic properties of aortas using the impulse response function of the filtered aortic input impedance spectra.

Results

Long-term lipopolysaccharide challenge enhanced the expression of advanced glycation end products (AGEs) in the aortas. Lipopolysaccharide also upregulated the inducible form of nitric oxide synthase to produce high levels of nitric oxide (NO), which resulted in vasodilation, as evidenced by the fall in total peripheral resistance (R_p). However, lipopolysaccharide challenge did not influence the elastic properties of aortas, as shown by the unaltered τ. The NO-mediated vascular relaxation may counterbalance the AGEs-induced arterial stiffening so that the aortic distensibility remained unaltered. Treating lipopolysaccharide-challenged rats with methylprednisolone prevented peripheral vasodilation because of its ability to increase R_p. However, methylprednisolone produced an increase in aorta stiffness, as manifested by the significant decline in τ. The diminished aortic distensibility by methylprednisolone paralleled a significant reduction in NO plasma levels, in the absence of any significant changes in AGEs content.

Conclusion

Methylprednisolone stiffens aortas and elastic arteries in lipopolysaccharide-induced chronic inflammation in rats, for NO activity may be dominant as a counteraction of AGEs.

R26R-GR: a Cre-activable dual fluorescent protein reporter mouse

Green fluorescent protein (GFP) and its derivatives are the most widely used molecular reporters for live cell imagining. The development of organelle-specific fusion fluorescent proteins improves the labeling resolution to a higher level. Here we generate a R26 dual fluorescent protein reporter mouse, activated by Cre-mediated DNA recombination, labeling target cells with a chromatin-specific enhanced green fluorescence protein (EGFP) and a plasma membrane-anchored monomeric cherry fluorescent protein (mCherry). This dual labeling allows the visualization of mitotic events, cell shapes and intracellular vesicle behaviors. We expect this reporter mouse to have a wide application in developmental biology studies, transplantation experiments as well as cancer/stem cell lineage tracing.

Rescue of the genetically engineered Cul4b mutant mouse as a potential model for human X-linked mental retardation

Mutation in CUL4B, which encodes a scaffold protein of the E3 ubiquitin ligase complex, has been found in patients with X-linked mental retardation (XLMR). However, early deletion of Cul4b in mice causes prenatal lethality, which has frustrated attempts to characterize the phenotypes in vivo. In this report, we successfully rescued Cul4b mutant mice by crossing female mice in which exons 4-5 of Cul4b were flanked by loxP sequences with Sox2-Cre male mice. In Cul4b-deficient (Cul4b(Δ)/Y) mice, no CUL4B protein was detected in any of the major organs, including the brain. In the hippocampus, the levels of CUL4A, CUL4B substrates (TOP1, β-catenin, cyclin E and WDR5) and neuronal markers (MAP2, tau-1, GAP-43, PSD95 and syn-1) were not sensitive to Cul4b deletion, whereas the number of parvalbumin (PV)-positive GABAergic interneurons was decreased in Cul4b(Δ)/Y mice, especially in the dentate gyrus (DG). Some dendritic features, including the complexity, diameter and spine density in the CA1 and DG hippocampal neurons, were also affected by Cul4b deletion. Together, the decrease in the number of PV-positive neurons and altered dendritic properties in Cul4b(Δ)/Y mice imply a reduction in inhibitory regulation and dendritic integration in the hippocampal neural circuit, which lead to increased epileptic susceptibility and spatial learning deficits. Our results identify Cul4b(Δ)/Y mice as a potential model for the non-syndromic model of XLMR that replicates the CUL4B-associated MR and is valuable for the development of a therapeutic strategy for treating MR.

High APACHE II score and long length of bowel resection impair the outcomes in patients with necrotic bowel induced hepatic portal venous gas

Background

Hepatic portal venous gas (HPVG) is a rare but potentially lethal condition, especially when it results from intestinal ischemia. Since the literatures regarding the prognostic factors of HPVG are still scarce, we aimed to investigate the risk factor of perioperative mortality in this study.

Methods

We analyzed data for patients with intestinal ischemia induced HPVG by chart review in our hospital between 2000 and 2007. Factors associated with perioperative mortality were specifically analyzed.

Results

There were 22 consecutive patients receiving definite bowel resection. 13 cases (59.1%) died after surgical intervention. When analyzing the mortality in patients after bowel resections, high Acute Physiology And Chronic health Evaluation (APACHE) II score (p < 0.01) and longer length of bowel resection (p = 0.047) were significantly associated with mortality in univariate analyses. The complication rate was 66.7% in alive patients after definite bowel resection.

Conclusions

Bowel resection was the only potential life-saving therapy for patients with mesenteric ischemia induced HPVG. High APACHE II score and severity of underlying necrotic bowel determined the results in patients after bowel resection.

Effects of acetyl-L-carnitine and oxfenicine on aorta stiffness in diabetic rats

BACKGROUND

We compared the haemodynamic and metabolic effects of acetyl-L-carnitine (one of the carnitine derivatives) and of oxfenicine (a carnitine palmitoyltransferase-1 inhibitor) in streptozotocin-induced diabetes in male Wistar rats.

MATERIALS AND METHODS

Diabetes was induced by a single tail vein injection of 55mgkg(-1) streptozotocin. The diabetic animals daily treated with either acetyl-L-carnitine (150mgkg(-1) in drinking water) or oxfenicine (150mgkg(-1) by oral gavage) for 8weeks,were compared with the untreated age-matched diabetic controls. Arterial wave reflection was derived using the impulse response function of the filtered aortic input impedance spectra. Thiobarbituric acid reactive substances (TBARS) measurement was used to estimate malondialdehyde (MDA) content.

RESULTS

Oxfenicine, but not acetyl-L-carnitine, increased total peripheral resistance in diabetes, which paralleled its elevation in plasma levels of free fatty acids. By contrast, acetyl-L-carnitine, but not oxfenicine, resulted in a significant increase in wave transit time and a decrease in wave reflection factor, suggesting that acetyl-L-carnitine may attenuate the diabetes-induced deterioration in systolic loading condition for the left ventricle. This was in parallel with its lowering of MDA/TBARS content in plasma and aortic walls in diabetes. Acetyl-L-carnitine therapy also prevented the diabetes-related cardiac hypertrophy, as evidenced by the reduction in ratio of the left ventricular weight to body weight.

CONCLUSION

 Acetyl-L-carnitine, but not oxfenicine, attenuates aortic stiffening and cardiac hypertrophy, possibly through its decrease of lipid oxidation-derived MDA/TBARS in the rats with insulin deficiency.

A new technique to remove a "stuck" totally implantable venous access catheter

Removal of a totally implantable venous access device (port) is usually a simple procedure; however, if a catheter has been in place for a very long period, it may adhere firmly to the vessel wall. We report a new technique to facilitate removal of a stuck catheter. A 16-year-old girl was admitted for removal of her port, which had been inserted for chemotherapy 11 years earlier. After her disease was controlled, the catheter could not be pulled out during surgery. To remove the catheter, we inserted a guidewire to straighten the catheter and then applied a "push-in" force to detach the adherence from the central vein. The catheter was then removed successfully. We believe that this is a new and simple method for removing a "stuck" catheter.

Chylous ascites after excision of a choledochal cyst in a child

We report a case of chylous ascites developing 2 weeks after excision of a choledochal cyst with a Roux-en-Y hepaticojejunostomy. Despite the failure of the initial attempts to resolve the chylous ascites by fasting, subsequently, we successfully treated the patient's chylous ascites with intravenous somatostatin. No obvious adverse side effects occurred during the use of somatostatin. To the best of our knowledge, this is the first report of chylous ascites after choledochal cyst excision in children, which was successfully treated with somatostatin. Somatostatin may be considered as a therapeutic option of managing pediatric postoperative chylous ascites.

Statistical identification of gene association by CID in application of constructing ER regulatory network

Background

A variety of high-throughput techniques are now available for constructing comprehensive gene regulatory networks in systems biology. In this study, we report a new statistical approach for facilitating in silico inference of regulatory network structure. The new measure of association, coefficient of intrinsic dependence (CID), is model-free and can be applied to both continuous and categorical distributions. When given two variables X and Y, CID answers whether Y is dependent on X by examining the conditional distribution of Y given X. In this paper, we apply CID to analyze the regulatory relationships between transcription factors (TFs) (X) and their downstream genes (Y) based on clinical data. More specifically, we use estrogen receptor α (ERα) as the variable X, and the analyses are based on 48 clinical breast cancer gene expression arrays (48A).

Results

The analytical utility of CID was evaluated in comparison with four commonly used statistical methods, Galton-Pearson's correlation coefficient (GPCC), Student's t-test (STT), coefficient of determination (CoD), and mutual information (MI). When being compared to GPCC, CoD, and MI, CID reveals its preferential ability to discover the regulatory association where distribution of the mRNA expression levels on X and Y does not fit linear models. On the other hand, when CID is used to measure the association of a continuous variable (Y) against a discrete variable (X), it shows similar performance as compared to STT, and appears to outperform CoD and MI. In addition, this study established a two-layer transcriptional regulatory network to exemplify the usage of CID, in combination with GPCC, in deciphering gene networks based on gene expression profiles from patient arrays.

Conclusion

CID is shown to provide useful information for identifying associations between genes and transcription factors of interest in patient arrays. When coupled with the relationships detected by GPCC, the association predicted by CID are applicable to the construction of transcriptional regulatory networks. This study shows how information from different data sources and learning algorithms can be integrated to investigate whether relevant regulatory mechanisms identified in cell models can also be partially re-identified in clinical samples of breast cancers.

Availability

the implementation of CID in R codes can be freely downloaded from .

Patient factors predicting the completion of sedation-free colonoscopy

BACKGROUND/AIMS

Colonoscopy without sedation costs less than sedated colonoscopy. The aim of this study is to identify the patient factors predicting the completion of colonoscopy without sedation.

METHODOLOGY

Between May and September 2005, a single colorectal surgeon performed 120 consecutive colonoscopies. Patient demographic, clinical and colonoscopy-related data were collected and analyzed.

RESULTS

Out of 120 colonoscopies performed, 11 were excluded due to obstruction of the colon by a tumor or poor preparation. Therefore, the study group contained 109 patients. Ninety-three (85.3%) colonoscopies were completed. Completion rate (odds ratio for completion [95% confidence interval]) was significantly associated with the male gender (5.03 [1.35-18.86]), high body mass index (4.42 [1.18-16.67]), no previous history of gynecological surgery (6.36 [1.84-22.14]), and previous colonic resection. Previous gynecological surgery was significantly associated with lower completion rates as shown using multivariate analysis. No complications relating to colonoscopy were observed.

CONCLUSIONS

In the majority of patients, a colorectal surgeon with adequate endoscopy experience can perform sedation-free colonoscopy successfully and safely. Gender, previous gynecological surgery, previous colonic resection, and body mass index were predictive factors for successful colonoscopy without sedation.

Impact of previous abdominal surgery on laparoscopic appendectomy for acute appendicitis

BACKGROUND

Laparoscopic appendectomy is one of the most commonly performed laparoscopic procedures. Impact of previous abdominal surgery on laparoscopic appendectomy has not been previously reported.

METHODS

From January 2001 to December 2005, 2029 patients with clinically suspected acute appendicitis underwent laparoscopic surgery in our hospital. Of these, 234 patients (11.5%) were found to have other pathology by intraoperative or histologic findings and were excluded from the study. The 1795 patients who underwent laparoscopic appendectomy for acute appendicitis were divided into three groups: group 1, patients without a history of previous abdominal surgery (n = 1652, 92%); group 2, patients with a history of upper abdominal surgery (n = 20, 1.1%); group 3, patients with a history of lower abdominal surgery (n = 123, 6.8%). Data were collected retrospectively by chart review and analyzed for conversion rate, operative time, intraoperative and postoperative complications, and hospital stay.

RESULTS

Of the 1795 patients, 13 (0.7%) were converted to open appendectomy because of technical difficulty. Overall mean operative time was 57.2 (range, 20-225) min. There was no mortality or intraoperative complications. Overall postoperative complication rate was 10.7% (n = 193): rate of surgical wound infection was 8.2% (n = 147), surgical wound seroma 1.3% (n = 24), and intra-abdominal abscess 0.8% (n = 14). Overall postoperative hospital stay averaged 3.2 (range, 0-39) days. There were no significant differences between the three groups regarding the conversion rate (0.8% vs. 0% vs. 0%, p = 0.567), operative time (57.3 vs. 55.8 vs. 56.9 min, p = 0.962), postoperative complication rates (10.7 vs. 10 vs. 12.2%, p = 0.863), and hospital stay (3.2 vs. 3.6 vs. 3.1 days, p = 0.673).

CONCLUSIONS

Previous abdominal surgery, whether upper or lower abdominal, has no significant impact on laparoscopic appendectomy for acute appendicitis.

Clinicopathological features and prognosis in resectable synchronous and metachronous colorectal liver metastasis

INTRODUCTION

Hepatic resection may offer long-term survival for patients with colorectal metastases. However, controversies exist regarding the prognostic factors. Herein, the impact of synchronicity of liver metastasis on patient clinicopathological features and prognosis was evaluated.

METHODS

One hundred and fifty-five patients who underwent hepatectomy for colon cancer metastasis, from 1995 to 2004, were enrolled in this study. Patients were divided into two groups: synchronous and metachronous colorectal liver metastasis. Patient demographics, the nature of the primary and metastatic tumors, surgery-related complications, and long-term outcome were analyzed.

RESULTS

Patients included in the synchronous group tended to be younger than those in the metachronous group. Compared to the metachronous group, patients in the synchronous group showed more metastases (P = 0.008) and bilobarly distributed metastases (P = 0.016). Bile leakage was the most common surgical complication. The estimated 5-year disease-free and overall survival rates were 16.8 and 41.1%, respectively. Univariate analysis indicated that synchronous metastases, advanced stage of the primary tumor, bilobar distribution of the metastases, more than three metastases, and colonic versus rectal location of the primary tumor were prognostic factors of shorter disease-free survival, but not overall survival. Multivariate analysis revealed that synchronous metastases and the advanced stage of the primary tumor were indicators for a worse disease-free survival.

CONCLUSION

The synchronous presence of primary colon cancer and liver metastasis may indicate a more disseminated disease status and is associated with a shorter disease-free survival than metachronous metastasis. These patients may need more careful monitoring and aggressive chemotherapy following curative resection.

Optimal interval from decompression to semi-elective operation in sigmoid volvulus

BACKGROUND/AIMS

The initial non-operative decompression and subsequent semi-elective operation is a common strategy in managing sigmoid volvulus. However, the optimal interval between decompression and operation is still unclear.

METHODOLOGY

From 1994 to 2004, 25 patients operated on for sigmoid volvulus at the National Taiwan University Hospital were enrolled. The treatment strategy and clinical outcome in these patients were retrospectively reviewed and analyzed.

RESULTS

Twenty-one patients underwent successful non-operative decompression initially, and the remaining 4 patients underwent emergent operation. Gangrene of the colon was found in 3 patients, and all of them eventually died of medical complications, i.e. multiple organ failure, pneumonia and myocardial infarction. One leakage but no mortality occurred in the patients undergoing semi-elective operation. The rate of postoperative complication was not significantly different between the patients operated on 2 days and more than 2 days after the decompression.

CONCLUSIONS

The initial non-operative decompression and subsequent semi-elective operation results in a satisfactory outcome in managing sigmoid volvulus. In the view of surgical result, a two-day interval seems adequate for bowel preparation and optimization of the patient's condition.