Duodenal diverticulitis accompanied by abscess formation treated successfully using an endoscopic nasobiliary drainage catheter: a case report.

Diverticulitis and diverticular abscesses are rare and potentially serious complications of duodenal diverticulum. These conditions often lead to perforation of the diverticulum, necessitating surgical treatment. There have been few reported cases of duodenal diverticulitis with or without perforation treated by endoscopic drainage. Here, we present a case of duodenal diverticulitis accompanied by abscess formation that was treated successfully with an endoscopic nasobiliary drainage catheter. We suggest this treatment could be an acceptable option for selected patients with a localized abscess that is resistant to conservative treatment.

Percutaneous transhepatic portal vein stent placement can improve prognosis for hepatocellular carcinoma patients with portal vein tumor thrombosis.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) has an extremely poor prognosis. One reason is that portal hypertension may progress rapidly and intractable gastric/esophageal variceal hemorrhage may occur in PVTT cases. We studied whether a percutaneous transhepatic portal vein stent placement could improve the prognosis for HCC with PVTT. METHODOLOGY: Five cases of HCC with PVTT where portal hypertension had rapidly progressed were performed portal vein stenting. RESULTS: All cases had been classified into Child-Pugh class C. Only one of them died of liver failure five months after stent placement, but two of the cases successfully avoided dying of liver failure and the other two cases are still alive with a hepatic functional reserve maintained. CONCLUSIONS: Although portal vein stent placement for HCC with PVTT is not by itself a therapy for PVTT, portal vein stent placement plays a prominent role in improving hepatic function reserve preventing fatal hepatic failures due to PVTT and gastric/esophageal variceal hemorrhage associated with portal hypertension. This leads to prolonged survival for HCC patients with PVTT. Further prospective trials including the appropriate timing of portal vein stent placement treatment will be needed for larger numbers of HCC patients with PVTT.

Histopathology of the tissue adhering to the multiple tine expandable electrodes used for radiofrequency ablation of hepatocellular carcinoma predicts local recurrence.

OBJECTIVE: To assess the ability to predict the local recurrence of hepatocellular carcinoma by analyzing tissues adhering to the radiofrequency ablation probe after complete ablation. METHODS: From May 2002 to March 2011, tissue specimens adhering to the radiofrequency ablation probe from 284 radiofrequency ablation sessions performed for hepatocellular carcinomas ≤3 cm in size were analyzed. The specimens were classified as either viable tumor tissue or complete necrosis, and the local recurrence rates were calculated using the Kaplan-Meier method. RESULTS: From the tumors ≤3 cm in size, viable tissue was present in 6 (2.1%) of 284 specimens, and the local recurrence rates after 1 and 2 years of follow-up were 6.7% and 11.2%, respectively. Local recurrence developed significantly earlier in the viable tissue group. The recurrence rate was not significantly different based on whether transcatheter arterial chemoembolization was performed. CONCLUSION: The histopathology of the tissue adhering to the radiofrequency ablation probes used for hepatocellular carcinoma treatment can predict local recurrence. Additional aggressive treatment for patients with viable tissue can therefore improve the overall survival.

Efficacy of the regimen using twice-daily ß-interferon followed by the standard of care for chronic hepatitis C genotype 1b with high viral load.

AIM: In patients with refractory genotype 1b chronic hepatitis C with high viral loads, we retrospectively compared the efficacy of standard of care treatment (SOC: combined PEG-IFN-α-2b/ribavirin for 48 weeks) and a regimen in which 2 weeks of SOC induction was replaced by twice-daily ß-interferon alone (IFN-ß induction therapy). METHODS: Seventeen patients received the IFN-ß induction therapy plus SOC (IFN-ß induction group) and 13 patients received SOC alone (SOC group). RESULTS: In the IFN-ß induction group and SOC group, early virological response (EVR) rates were 88.2% and 53.8%, respectively. The end of treatment rates were 100.0% and 92.3%, and sustained virological response (SVR) rates were 70.6% and 53.8%, respectively. By induction with IFN-ß, even in refractory cases, the high virus negative conversion rate in the early treatment phase and actions of pegylated IFN-α-2b and ribavirin in the maintenance treatment phase led to an additive effect. In the analysis of contributing factors, only the achievement of EVR was associated with a significant difference in SVR (P = 0.0011). The univariate logistic regression analysis showed that only IFN-ß treatment was associated with a significant difference in EVR (P = 0.0492, odds ratio = 6.248, 95% confidence interval = 1.026-40.252), whereas no significant factors were found in the multivariate analysis due to small samples. CONCLUSION: IFN-ß induction therapy with higher EVR might be beneficial for protease inhibitor-refractory chronic hepatitis C patients.

Japanese case of Budd-Chiari syndrome due to hepatic vein thrombosis successfully treated with liver transplantation.

A 22-year-old Japanese woman was found to have severe esophageal varices and then suffered from hepatic encephalopathy. She was diagnosed with Budd-Chiari syndrome (BCS) due to hepatic vein (HV) thrombosis accompanied by portal vein thrombosis without inferior vena cava (IVC) obstruction. Latent myeloproliferative neoplasm (MPN) lacking the JAK2-V617F mutation was considered to be the underlying disease. Liver transplantation was strikingly effective for treating the clinical symptoms attributable to portal hypertension. Although thrombosis of the internal jugular vein occurred due to thrombocythemia, which manifested after transplantation despite anticoagulation therapy with warfarin, the thrombus immediately disappeared with the addition of aspirin. Neither thrombosis nor BCS has recurred in more than 4 years since the amelioration of the last thrombotic event, and post-transplant immunosuppression with tacrolimus has not accelerated the progression of MPN. In Japan, IVC obstruction, which was a predominant type of BCS, is suggested to have decreased in incidence with recent improvements in hygiene. The precise diagnosis of BCS and causative underlying diseases should be made with attention to the current trend of the disease spectrum, which fluctuates with environmental sanitation levels. Because the stepwise strategy, including liver transplantation, has been proven effective for patients with pure HV obstruction in Western countries, this strategy should also be validated for utilization in Japan and in developing countries where HV obstruction potentially predominates.

Surfactant protein-D is more useful than Krebs von den Lungen 6 as a marker for the early diagnosis of interstitial pneumonitis during pegylated interferon treatment for chronic hepatitis C.

BACKGROUND/AIMS: To examine the usefulness of serum Krebs von den Lungen 6 (KL-6) and surfactant protein-D (SP-D) as markers of interstitial pneumonitis. Many antiviral therapies have become available for chronic hepatitis C, including pegylated interferon (PEGIFN) plus ribavirin. Since interstitial pneumonitis is a serious adverse drug reaction during interferon therapy, interferon treatment requires caution in respiratory disease patients. Hence, the predictors of interstitial pneumonitis have not been elucidated. METHODOLOGY: Fifty-two chronic hepatitis C patients who received PEG-IFN plus ribavirin were studied; 14 patients received PEGIFN-α 2a, and 38 received PEG-IFN-α 2b. Serum KL-6 and SP-D levels were measured during treatment. Time changes in serum KL-6 and SP-D levels, as well as the presence of interstitial pneumonitis, were investigated. RESULTS: No cases of pneumonitis in which both markers were below the standard values were seen. Interstitial pneumonitis developed in 1 of the 5 patients in whom both markers were above standard values. Patients whose KL-6 levels alone exceeded the standard value had bacterial pneumonia and emphysema, not interstitial pneumonitis. Though no correlation between SP-D and KL-6 levels was observed, KL-6 levels tended to increase after interstitial pneumonitis was detected on imaging, but SP-D levels increased before imaging detection. CONCLUSIONS: It is important to monitor changes in levels of serum markers and other factors to avoid interstitial pneumonitis during PEG-IFN therapy. SP-D in particular may be important for early detection of interstitial pneumonitis.

Alpha-fetoprotein-producing adenocarcinoma in which the metastatic route was determined from calcified lesions.

Alpha-fetoprotein (AFP)-producing adenocarcinoma is known for its rapid progression and poor prognosis, and chemotherapy regimens are yet to be standardized. Here we describe the first report of AFP-producing adenocarcinoma with calcification. The metastatic route was visualized from the calcification, and combination chemotherapy was performed. A 77-year-old Japanese man was transferred to our hospital for treatment of liver tumors. Computed tomography (CT) revealed multiple liver tumors with portal vein tumor thrombosis. The tumors were highly attenuated before enhancement, suggesting various degrees of calcification. Serum levels of carcinoembryonic antigen (CEA), AFP, and the proportion of fucosylated AFP were considerably elevated. Gastroduodenoscopy revealed an elevated tumor occupying the duodenal bulb with an ulcerative lesion in the vicinity of the gastroduodenal junction, and biopsy specimens from the duodenum and liver revealed medullary adenocarcinoma with calcification. Three-dimensional reconstruction of CT images clearly showed that the calcified lesions had spread from the gastroduodenal junction to the liver via a route comprising the corresponding local vein, the superior mesenteric vein, and portal vein. The patient was accordingly diagnosed with calcified AFP-producing adenocarcinoma with multiple liver metastases. Combination chemotherapy using TS-1 and cisplatin (CDDP) resulted in a striking response for the initial 4 months in terms of tumor markers and CT findings. This is the first report of AFP-producing adenocarcinoma with calcification. A metastatic route from the primary tumor to the liver was clearly visualized by tracing the calcified lesions. Combination chemotherapy based on 5-fluorouracil and CDDP may have the potential to prolong survival.

Therapeutic efficacy of continuous arterial infusion of the protease inhibitor and the antibiotics and via celiac and superior mesenteric artery for severe acute pancreatitis--pilot study.

BACKGROUND/AIMS: Severe acute pancreatitis is poor prognosis. Continuous regional arterial infusion of protease inhibitors and antibiotics were developed in Japan. We evaluated whether arterial infusion both celiac artery and superior mesenteric artery for this disease would reduce mortality. METHODOLOGY: Seventeen patients were treated arterial infusion of protease inhibitor and antibiotics via both celiac artery and superior mesenteric artery. Changes of Acute Physiology and Chronic Health Evaluation II score and mortality were evaluated. RESULTS: Arterial infusion via two routes reduced the mortality rate and improved Acute Physiology and Chronic Health Evaluation II score. The overall mortality rate was 11.8%. The mortality rate in patients in whom were treated within 3days after the onset was significantly lower than that in patients in whom were treated without 3days after the onset. CONCLUSIONS: Arterial infusion via superior mesenteric artery might prevent both bacterial translocation and non-occlusive mesenteric ischemia. Continuous arterial infusion both celiac artery and superior mesenteric artery might be effective for reducing mortality and preventing the development of pancreatitis, especially when initiated within 3 days after the onset. Further prospective randomized studies using a larger number of patients are required.

Successful treatment of multiple lung metastases of hepatocellular carcinoma by combined chemotherapy with docetaxel, cisplatin and tegafur/uracil.

We report the successful treatment of multiple lung metastases after hepatic resection for hepatocellular carcinoma (HCC) with combined docetaxel, cisplatin (CDDP), and enteric-coated tegafur/uracil (UFT-E). A 68-year-old man was diagnosed with multiple lung metastases of HCC 7 mo after partial hepatectomy for HCC. Oral UFT-E was given daily and docetaxel and CDDP were given intra-arterially (administered just before the bronchial arteries) every 2 wk via a subcutaneous injection port. One month after starting chemotherapy, levels of tumor marker, protein induced by vitamin K absence II (PIVKA-II), decreased rapidly, and after a further month, chest X-ray and computed tomography revealed the complete disappearance of multiple liver metastases. Two years after the combined chemotherapy, HCC recurred in the liver and was treated but no pulmonary recurrence occurred. In the absence of a standardized highly effective therapy, this combined chemotherapy with docetaxel, CDDP and UFT-E may be an attractive option for multiple lung metastases of HCC.

Improved survival for hepatocellular carcinoma with portal vein tumor thrombosis treated by intra-arterial chemotherapy combining etoposide, carboplatin, epirubicin and pharmacokinetic modulating chemotherapy by 5-FU and enteric-coated tegafur/uracil: a pilot study.

AIM: To investigate the poor prognosis of HCC with PVTT, we evaluated the efficacy by a new combination chemotherapy for advanced hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). METHODS: From 2002 to 2007, a total of 10 consecutive patients with Stage IVA HCC accompanied by PVTT were studied prospectively to examine the efficacy of treatment by intra-arterial infusion of a chemotherapeutic agents consisting of etoposide, carboplatin, epirubicin and pharmacokinetic modulating chemotherapy by 5-FU and enteric-coated tegafur/uracil. RESULTS: The mean course of chemotherapy was 14.4 (range, 9-21) mo. One patient showed complete response (CR) with disappearance of HCC and PVTT after treatment, and the two patients showed partial response (PR), response rate (CR + PR/All cases 30%). The median survival time after the therapy was 457.2 d. The one-year survival rate was 70%. Adverse reactions were tolerable. CONCLUSION: Although the prognosis of most patients with Stage IVA HCC by PVTT is poor, our combination chemotherapy may induces long-term survival and is an effective treatment and produced anti-tumor activity with tolerable adverse effects in patients for advanced Stage IVA HCC accompanied by PVTT.

Angiotensin-II administration is useful for the detection of liver metastasis from pancreatic cancer during pharmacoangiographic computed tomography.

AIM: To improve the preoperative diagnosis of liver metastasis from pancreatic cancer, we estimated computed tomography during arterial angiography (CTA) with/without administration of angiotensin-II (AT- II). METHODS: Thirty-five patients with pancreatic cancer were examined in this study. After conventional CTA was performed, pharmacoangiographic CTA was performed with a 1-3 microgram/5 mL solution of angiotensin II injected through a catheter into the celiac artery during spiral computed tomography. We prospectively analyzed the relative region of interest (ROI) ratio of tumor to liver with/without AT-II. RESULTS: In all patients, the relative ratio of each computed tomography (CT) number in the ROI was larger at pharmacoangiographic CT than at conventional angiographic CT. Administration of angiotensin-II enhanced the metastatic liver tumor as compared with normal tissue. Intratumoral blood flow increased in all patients with malignant tumors due to the pressure effect of AT-II. Furthermore, the metastatic lesions in the liver of three patients were represented by only pharmacoangiographic CT, not by conventional CT and conventional CT angiography. In even peripheral and central areas of metastatic liver tumor, the lesions were enhanced after administration of AT-II. CONCLUSION: These results support that high detection rate of liver metastasis revealed by pharmacoangiographic CT suggests the improvement of diagnosis on preoperative staging. Moreover, chemotherapy under AT-II induced hypertension may have a better effect on the treatment of metastatic liver tumors.

[A case of splenic inflammatory pseudotumor].

A 59-year-old man was admitted to our hospital because of continuous C-reactive protein elevation. Abdominal computed tomography scan revealed a low density mass on the surface of the spleen. Magnetic resonance imaging showed low intensity at peripheral area and slightly high intensity in the central area of the mass lesion on T1 and T2-weighted image. Splenectomy was performed since we could not rule out the possibility of malignant neoplasm only by diagnostic imaging. The pathological diagnosis of the tumor was inflammatory pseudotumor. Splenectomy is considered to be significant from the standpoints of both diagnosis and therapy in cases in which diagnostic imaging is difficult to interpret.

Clinical efficacy of intra-arterial pharmacokinetic chemotherapy with 5-fluorouracil, CDDP, gemcitabine, and angiotensin-II in patients with advanced pancreatic cancer.

BACKGROUND/AIMS: To deliver anticancer drugs more selectively into cancer tissues and to improve survival time, we have developed a new method of intra-arterial chemotherapy for unresectable pancreatic cancer. METHODOLOGY: From April 2002 to June 2006, twenty patients with pancreatic cancer with liver metastases were given intra-arterial infusions consisting of gemcitabine, 5-FU, and cisplatin mixed with angiotensin-II with the intent of increasing the blood flow into the tumor tissue but decreasing that to the non-tumor tissues. Simultaneously, tegafur/uracil was administered. A tumor marker and computed tomography (CT) findings were used to evaluate the efficacy of this chemotherapy. RESULTS: The median survival was 365 days, and 6-months and 1-year survival rates were 80.0% and 44.7%, respectively. In 12 of 20 cases, the tumor marker level was decreased after this chemotherapy. In 10 of 20 cases, computed tomography showed a decrease in the tumor size. In 6 patients, back pain was the chief complaint and was reduced to a self-controlled level in 20 patients. No major complications were encountered. CONCLUSIONS: Compared with the previously reported data in traditional chemotherapies, our method of intra-arterial chemotherapy appears to be quite useful not only for prolonging patient survival but also for improving the quality of life. Intra-arterial regional chemotherapy including changes in distribution of blood flow induced by angiotensin-II appears to be an effective palliative treatment for advanced pancreatic cancer.

Comparison of a new aspiration needle device and the Quick-Core biopsy needle for transjugular liver biopsy.

AIM: To evaluate sample adequacy, safety, and needle passes of a new biopsy needle device compared to the Quick-Core biopsy needle for transjugular liver biopsy in patients affected by liver disease. METHODS: Thirty consecutive liver-disease patients who had major coagulation abnormalities and/or relevant ascites underwent transjugular liver biopsy using either a new needle device (18 patients) or the Quick-Core biopsy needle (12 patients). The length of the specimens was measured before fixation. A pathologist reviewed the histological slides for sample adequacy and pathologic diagnoses. The two methods'specimen adequacy and complication rates were assessed. RESULTS: Liver biopsies were technically successful in all 30 (100%) patients, with diagnostic histological core specimens obtained in 30 of 30 (100%) patients, for an overall success rate of 100%. With the new device, 18 specimens were obtained, with an average of 1.1 passes per patient. Using the Quick-Core biopsy needle, 12 specimens were obtained, with an average of 1.8 passes per patient. Specimen length was significantly longer with the new needle device than with the Quick-Core biopsy needle (P < 0.05). The biopsy tissue was not fragmented in any of the specimens with the new aspiration needle device, but tissue was fragmented in 3 of 12 (25.0%) specimens obtained using the Quick-Core biopsy needle. Complications included cardiac arrhythmia in 3 (10.0%) patients, and transient abdominal pain in 4 (13.3%) patients. There were no cases of subcapsular hematoma, hemoperitoneum, or sepsis, and there was no death secondary to the procedure. In particular, no early or delayed major procedure-related complications were observed in any patient. CONCLUSION: Transjugular liver biopsy is a safe and effective procedure, and there was significant difference in the adequacy of the specimens obtained using the new needle device compared to the Quick-Core biopsy needle. Using the new biopsy needle device, the specimens showed no tissue fragmentation and no increment in major procedure-related complications was observed.

[Gemcitabine versus combined chemotherapy with 5-fluorouracil and cisplatin in advanced pancreatic cancer].

Gemcitabine hydrochloride (GEM) is a first-line therapeutic agent for advanced pancreatic cancer, but there is no established second-line treatment after GEM failure. We assessed the clinical benefit of systemic combined chemotherapy with 5-fluorouracil and cisplatin (FP therapy) in 19 patients compared with GEM in 32 patients, respectively. Tumor response rates were 10.5% and 15.6% for FP therapy and GEM, respectively. The median survival time in the FP therapy and GEM was 137 days and 241 days, respectively. Although clinical benefit was similar in both types of therapy, median survival time was more favorable for GEM, especially for Stage IVb. Nausea and vomiting were the most commonly observed toxicity in the FP therapy group. Our data indicate that FP therapy is not considered to be a useful second-line agent in patients with GEM pretreated pancreatic cancer.

Balloon-occluded retrograde transvenous obliteration of gastric varix draining to the IVC via the circumaortic renal vein.

The authors encountered a patient with gastric varices draining to the IVC not only via the usual route of the left renal vein but also via a circumaortic renal vein. Balloon-occluded retrograde transvenous obliteration (B-RTO) of the gastric varix was performed with balloon occlusion of the circumaortic renal vein and retrograde injection of sclerosing agent (5% of ethanolamine oleate) into the varix. Eradication of the gastric varix was confirmed on endoscopic examination 2 months later. We document the first case of B-RTO performed for gastric varix via the circumaortic renal vein. Details of this rare occurrence and implications for treatment are presented herein.

[Modified pharmacokinetic modulating chemotherapy for progressive gastric cancer accompanied by peritoneal dissemination].

Peritoneal dissemination is a major event in the development of gastric cancer. However, most patients with it have been excluded from clinical studies because they rarely have measurable lesions. We conducted an analysis to evaluate the efficacy and feasibility of modified pharmacokinetic modulating chemotherapy, for gastric cancer patients with peritoneal dissemination. Between May 2002 and April 2004, 10 patients were treated by modified pharmacokinetic modulating chemotherapy. This analysis was based on 10 consecutive chemotherapy-naive patients with confirmed peritoneal dissemination. This therapy regimen was repeated with a weekly schedule of MTX 100 mg/body, given as intraarterial infusion 1 h prior to a 24-hr infusion of 5-FU 500 mg/body. Simultaneously, enteric-coated tegafur/uracil (400 mg) was administered every day. The one-year overall survival rate was 50. 0%. The median survival time was 311 days. Grade 1 stomatitis and Grade 1/2 oral dryness were involved in 40% of the cases. No patient had to discontinue this therapy because of complications. Objective improvement of ascites was seen in all patients, and all patients could be treated at outpatient clinics. This regimen may be well-tolerated and of clinical benefit for patients with peritoneal dissemination of gastric cancer.

[A case of advanced gastric cancer with bone metastasis and severe DIC responding to hypertensive subselective chemotherapy with pharmacokinetic modulating chemotherapy].

We report a 47-year-old female patient who was suffering from severe DIC due to multiple bone metastases. This patient was treated weekly with an intraarterial 5-FU (500 mg) and MTX (100 mg) including AT-II by a subcutaneously implanted port system placed into her abdominal aorta. Furthermore, she was administered tegafur/uracil (400 mg/day) 5 days weekly for pharmacokinetic modulating chemotherapy (PMC). After three courses of PMC treatment, DIC was resolved and the tumor marker was reduced. However, after 22 courses of this regimen, DIC suddenly recurred. As second line chemotherapy, we then administered paclitaxel (80 mg) in place of CDDP. After five courses of this second line chemotherapy, DIC recovered and the tumor marker was again decreased. We concluded that this chemotherapy is effective for advanced gastric cancer complicated with bone metastasis and DIC from the standpoint of toxicities, antitumor effect and QOL of the patient.

CT-maximum intensity projection is a clinically useful modality for the detection of gastric varices.

AIM: To evaluate the efficacy of CT-maximum intensity projection (CT-MIP) in the detection of gastric varices and their inflowing and outflowing vessels in patients with gastric varices scheduled to undergo balloon-occluded retrograde transvenous obliteration (B-RTO). METHODS: Sixteen patients with endoscopically confirmed gastric varices were included in this study. All patients were evaluated with CT-MIP using three-dimensional reconstructions, before and after B-RTO. RESULTS: CT-MIP clearly depicted gastric varices in 16 patients (100%), the left gastric vein in 6 (32.5%), the posterior gastric vein in 12 (75.0%), the short gastric veins in 13 (81.3%), gastrorenal shunts in 16 (100%), the hemiazygos vein (HAZV) in 4 (25.0%), the pericardiophrenic vein (PCPV) in 9 (56.3%), and the left inferior phrenic vein in 9 patients (56.3%). Although flow direction itself cannot be determined from CT-MIP, this modality provided clear images of the inflowing and the outflowing vessels. Moreover, in one patient, short gastric veins were not seen on conventional angiographic portography images of the spleen, but were clearly revealed on CT-MIP. CONCLUSION: We suggest that CT-MIP should be considered as a routine method for detecting and diagnosing collateral veins in patients with gastric varices scheduled for B-RTO. Furthermore, CT-MIP is more useful than endoscopy in verifying the early therapeutic effects of B-RTO.

Two distinct methods analyzing chromatin structure using centrifugation and antibodies to modified histone H3: both provide similar chromatin states of the Rit1/Bcl11b gene.

Chromatin state of a 2-Mb region harboring Rit1/Bcl11b on mouse chromosome 12 was examined using two distinct methods. One is ChIP assay examining the degree of enrichment with histone H3 methylated at lysine 9 (H3-mLys9) in chromatin and the other is H/E (heterochromatin/euchromatin) assay that measures a chromatin condensation state by using centrifugation. The ChIP assay showed that a 50-kb interval covering the gene and an upstream region constituted chromatin enriched with unmethylated H3-mLys9 in cells expressing Rit1 compared to cells not expressing Rit1. In contrast, regions other than the 50-kb interval did not show much difference in the enrichment between the two different types of cells. On the other hand, H/E assay of two expressing and two non-expressing tissues provided compatible fractionation patterns, suggesting that the chromatin condensation state detected by H/E assay is correlated with the chromatin state controlled by histone H3 tail modification linked to gene expression. These results indicate that the centrifugation-based H/E assay should provide a new approach to the regulation of chromatin structure with respect to its condensation state, complementing ChIP assays.