Single-shot optical imaging with spectrum circuit bridging timescales in high-speed photography

Single-shot optical imaging based on ultrashort lasers has revealed nonrepetitive processes in subnanosecond timescales beyond the recording range of conventional high-speed cameras. However, nanosecond photography without sacrificing short exposure time and image quality is still missing because of the gap in recordable timescales between ultrafast optical imaging and high-speed electronic cameras. Here, we demonstrate nanosecond photography and ultrawide time-range high-speed photography using a spectrum circuit that produces interval-tunable pulse trains while keeping short pulse durations. We capture a shock wave propagating through a biological cell with a 1.5-ns frame interval and 44-ps exposure time while suppressing image blur. Furthermore, we observe femtosecond laser processing over multiple timescales (25-ps, 2.0-ns, and 1-ms frame intervals), showing that the plasma generated at the picosecond timescale affects subsequent shock wave formation at the nanosecond timescale. Our technique contributes to accumulating data of various fast processes for analysis and to analyzing multi-timescale phenomena as a series of physical processes.

Super-resolution vibrational imaging based on photoswitchable Raman probe

Super-resolution vibrational microscopy is promising to increase the degree of multiplexing of nanometer-scale biological imaging because of the narrower spectral linewidth of molecular vibration compared to fluorescence. However, current techniques of super-resolution vibrational microscopy suffer from various limitations including the need for cell fixation, high power loading, or complicated detection schemes. Here, we present reversible saturable optical Raman transitions (RESORT) microscopy, which overcomes these limitations by using photoswitchable stimulated Raman scattering (SRS). We first describe a bright photoswitchable Raman probe (DAE620) and validate its signal activation and depletion characteristics when exposed to low-power (microwatt level) continuous-wave laser light. By harnessing the SRS signal depletion of DAE620 through a donut-shaped beam, we demonstrate super-resolution vibrational imaging of mammalian cells with excellent chemical specificity and spatial resolution beyond the optical diffraction limit. Our results indicate RESORT microscopy to be an effective tool with high potential for multiplexed super-resolution imaging of live cells.

Design and Fabrication of an Electrochemical Chip for Liquid-Phase Transmission Electron Microscopy

Liquid-phase transmission electron microscopy (LP-TEM) can be used with an electrochemical chip (e-chip) to observe electrochemical reactions in a liquid in situ. The design of electrodes on an e-chip fabricated using microelectromechanical system (MEMS) technology cannot be easily changed. Here, we report a newly designed e-chip and its fabrication process. Electrodes with a desired shape were fabricated with various metals via an additional step of vacuum deposition onto our e-chip with a shadow mask. For precise control of the electrochemical reactions in LP-TEM, optimization of the electrode shape and material is critical.

3D micro fractal pipettes for capillary based robotic liquid handling

Miniaturized and mobile liquid handling devices are essential elements to biological or clinical applications. This will innovate the conventional liquid handling methods such as manual or automated pipetting systems. Here, we propose the micro fractal pipette as the candidate device for this objective. It is made of epoxy polymer and printed by innovative 3D nanoprinting technology based on two-photon absorption polymerization with sub-micrometer resolution. We demonstrated the efficient liquid handling performance by using the micro fractal pipette between the source droplet and the target hydrogel substrate. This is due to the high porosity (78%) and the 8.5 times larger cavity surface area compared to the full pyramid. The biomimetic inner cavity microchannel networks contribute to the low pressure drop. The proposed micro fractal pipette could also innovate the versatile and miniaturized liquid handling system, promising to various biological or clinical applications.

Increasing cell-device adherence using cultured insect cells for receptor-based biosensors

Field-effect transistor (FET)-based biosensors have a wide range of applications, and a bio-FET odorant sensor, based on insect (Sf21) cells expressing insect odorant receptors (ORs) with sensitivity and selectivity, has emerged. To fully realize the practical application of bio-FET odorant sensors, knowledge of the cell-device interface for efficient signal transfer, and a reliable and low-cost measurement system using the commercial complementary metal-oxide semiconductor (CMOS) foundry process, will be indispensable. However, the interfaces between Sf21 cells and sensor devices are largely unknown, and electrode materials used in the commercial CMOS foundry process are generally limited to aluminium, which is reportedly toxic to cells. In this study, we investigated Sf21 cell-device interfaces by developing cross-sectional specimens. Calcium imaging of Sf21 cells expressing insect ORs was used to verify the functions of Sf21 cells as odorant sensor elements on the electrode materials. We found that the cell-device interface was approximately 10 nm wide on average, suggesting that the adhesion mechanism of Sf21 cells may differ from that of other cells. These results will help to construct accurate signal detection from expressed insect ORs using FETs.

Sublingual immunotherapy for allergic rhinitis: subjective versus objective tools to evaluate its success

BACKGROUND

Biomarkers that enable objective evaluation of the clinical effects of immunotherapy for allergic rhinitis have yet to be identified.

METHODS

This study included 40 patients who were enrolled in a large randomized, double-blind, placebo-controlled, multicenter study examining the efficacy of sublingual immunotherapy (SLIT) using Japanese cedar (JC) pollen extract during two consecutive pollen seasons from 2010 to 2012. Based on changes in total nasal symptom medication score, patients in the SLIT and placebo groups were subdivided into two subgroups: good responders and poor responders. The levels of JC pollen-specific IL-10+Foxp3+ cells and specific Th2 cytokine-producing cells were measured and the association with the efficacy of SLIT was analysed.

RESULTS

The total nasal symptom medication score was significantly lower in the SLIT group compared with the placebo group. The number of JC pollen-specific Th2 cytokine-producing cells increased during the pollen season in the placebo group and in poor responders in the SLIT group; however, the increases were inhibited in the good responders in the SLIT group. The number of JC pollen-specific IL-10+Foxp3+ cells increased only in these good responders.

CONCLUSIONS

Changes in levels of allergen-specific Th2 cytokine-producing cells and IL-10+Foxp3+ cells could be objective biomarkers for SLIT.

A Nearest Neighbor Classifier Employing Critical Boundary Vectors for Efficient On-Chip Template Reduction

Aiming at efficient data condensation and improving accuracy, this paper presents a hardware-friendly template reduction (TR) method for the nearest neighbor (NN) classifiers by introducing the concept of critical boundary vectors. A hardware system is also implemented to demonstrate the feasibility of using an field-programmable gate array (FPGA) to accelerate the proposed method. Initially, k -means centers are used as substitutes for the entire template set. Then, to enhance the classification performance, critical boundary vectors are selected by a novel learning algorithm, which is completed within a single iteration. Moreover, to remove noisy boundary vectors that can mislead the classification in a generalized manner, a global categorization scheme has been explored and applied to the algorithm. The global characterization automatically categorizes each classification problem and rapidly selects the boundary vectors according to the nature of the problem. Finally, only critical boundary vectors and k -means centers are used as the new template set for classification. Experimental results for 24 data sets show that the proposed algorithm can effectively reduce the number of template vectors for classification with a high learning speed. At the same time, it improves the accuracy by an average of 2.17% compared with the traditional NN classifiers and also shows greater accuracy than seven other TR methods. We have shown the feasibility of using a proof-of-concept FPGA system of 256 64-D vectors to accelerate the proposed method on hardware. At a 50-MHz clock frequency, the proposed system achieves a 3.86 times higher learning speed than on a 3.4-GHz PC, while consuming only 1% of the power of that used by the PC.

Sublingual immunotherapy for allergic rhinitis: subjective versus objective tools to evaluate its success

BACKGROUND

Biomarkers that enable objective evaluation of the clinical effects of immunotherapy for allergic rhinitis have yet to be identified.

METHODS

This study included 40 patients who were enrolled in a large randomized, double-blind, placebo-controlled, multicenter study examining the efficacy of sublingual immunotherapy (SLIT) using Japanese cedar (JC) pollen extract during two consecutive pollen seasons from 2010 to 2012. Based on changes in total nasal symptom medication score, patients in the SLIT and placebo groups were subdivided into two subgroups: good responders and poor responders. The levels of JC pollen-specific IL-10+Foxp3+ cells and specific Th2 cytokine-producing cells were measured and the association with the efficacy of SLIT was analysed.

RESULTS

The total nasal symptom medication score was significantly lower in the SLIT group compared with the placebo group. The number of JC pollen-specific Th2 cytokine-producing cells increased during the pollen season in the placebo group and in poor responders in the SLIT group; however, the increases were inhibited in the good responders in the SLIT group. The number of JC pollen-specific IL-10+Foxp3+ cells increased only in these good responders.

CONCLUSIONS

Changes in levels of allergen-specific Th2 cytokine-producing cells and IL-10+Foxp3+ cells could be objective biomarkers for SLIT.

Conveyor for Pneumatic Two-Dimensional Manipulation Realized by Arrayed MEMS and its Control

We propose a microconveyor based on silicon microelectromechanical systems (MEMS) technology and demonstrate successful operation of the microconveyor. Microactuators work as air nozzles, which generate directed air flow by changing the pathways of compressed nitrogen gas. One-dimensional conveyance of an object 2.1mm × 4.1mm × 200μm weighing approximately 4mg is demonstrated with a directed air flow of 17kPa. Using a two-dimensional conveyor, we levitate and move an object 3mm × 3mm × 100μm weighing approximately 2mg using a continuous air flow. Conveyance toward the force equilibrium point was achieved with a regularly pulsed air flow. We are now studying full control of two-dimensional conveyance. We also propose control by actuating air nozzles to change the direction of air flow and move the equilibrium point to transfer the object to the desired point.

Surface expression of toll-like receptor 4 on THP-1 cells is modulated by Bu-Zhong-Yi-Qi-Tang and Shi-Quan-Da-Bu-Tang

Human Toll-like receptor 4 (TLR4) has recently been identified and has been shown to be the main protein involved in recognizing Gram-negative bacteria. We examined the regulation of TLR4 surface expression in a human monocytic cell line (THP-1 cells) by two traditional Chinese herbal medicines. Bu-Zhong-Yi-Qi-Tang (TJ-41) and Shi-Quan-Da-Bu-Tang (TJ-48). TJ-41 and TJ-48 upregulated TLR4 surface expression in THP-1 cells, as well as enhanced TLR4 surface expression in these cells both dose- and time-dependently. These findings suggest that TJ-41 and TJ-48 increase the receptor involved in the response to Gram-negative bacteria and may enhance defenses against these pathogens.

N-Acetylglucosaminyltransferase V as a possible aid for the evaluation of tumor invasiveness in patients with hepatocellular carcinoma

BACKGROUND

A close relationship has been shown to exist between the metastatic potential and beta1-6 branched oligosaccharides in human and rodent cells. N-acetylglucosaminyltransferase V (GnT-V) catalyzes this process. Although this phenomenon has been reported, little is known about the clinical usefulness of the determination of GnT-V in the evaluations of tumor invasiveness in hepatocellular carcinoma (HCC). In this study, we measured the GnT-V activity in serum of patients with HCC, together with its activity and gene expression in HCC tissues, and elucidated the clinical usefulness of the GnT-V level in evaluating tumor invasiveness.

METHODS

Seventy-three serum samples from 38 patients with HCC, 11 with chronic hepatitis, eight with hepatic cirrhosis and 16 healthy controls were used. Twenty-one liver tissues were obtained by surgical resection from 17 patients with HCC, three with colorectal cancers and one with gallbladder cancer metastatic to the liver. The GnT-V activity was determined by using high performance liquid chromatography. The GnT-V mRNA was quantified by using competitive RT-PCR.

RESULTS

There were statistically significant correlations between GnT-V activity in sera of HCC, and GnT-V activity and GnT-V mRNA expression in tumor tissue. The mean GnT-V activity in the sera of patients with HCC increased in accordance with the degree of tumor invasion. The HCC group with intrahepatic and extrahepatic metastases showed the highest serum GnT-V-value.

CONCLUSIONS

The present study demonstrated that there was a close association between tumor invasiveness and GnT-V activity in sera, and that the measurement of GnT-V may improve prognostic estimates and therapeutic outcomes for patients with HCC.

Toll-like receptor 2 and 4 surface expressions on human monocytes are modulated by interferon-gamma and macrophage colony-stimulating factor

Human Toll-like receptor 2 (TLR2) and TLR4 are recently identified receptors. TLR4 was shown to be the main protein involved in recognizing Gram-negative bacteria, whereas TLR2 is apparently the key factor in responses to other types of microbial pathogens. We examined regulations of TLR2 and TLR4 surface expressions in human peripheral blood monocytes by interferon-gamma (IFN-gamma) and macrophage colony-stimulating factor (M-CSF). IFN-gamma up-regulated both TLR2 and TLR4, but enhanced the surface expression, on human peripheral blood monocytes of TLR4 more than that of TLR2. On the other hand, M-CSF up-regulated both TLR2 and TLR4 surface expression on human peripheral blood monocytes, with no change in the ratio of TLR2/TLR4 surface expression. These results indicate that IFN-gamma enhances receptors involved in the response to Gram-negative bacteria more than those involved in responses to other types of microbial pathogens, whereas M-CSF enhances the receptor response to Gram-negative bacteria in the same manner as to other types of microbial pathogens.

A critical role for mouse CXC chemokine(s) in pulmonary neutrophilia during Th type 1-dependent airway inflammation

Ag-specific Th1 and Th2 cells have been demonstrated to play a critical role in the induction of allergic diseases. Here we have investigated the precise mechanisms of Th1-induced airway inflammation. Airway inflammation was induced in BALB/c mice by transfer of freshly induced OVA-specific Th1 or Th2 cells followed by OVA inhalation. In this model, both Th1 and Th2 cells induced airway inflammation. The former induced neutrophilia in airways, whereas the latter induced eosinophilia. Moreover, we found that Th1 cells induced more severe airway hyperresponsiveness (AHR) than Th2 cells. The eosinophilia induced by Th2 cell infusion was almost completely blocked by administration of anti-IL-5 mAb, but not anti-IL-4 mAb. In contrast, Th1-induced AHR and pulmonary neutrophilia were inhibited by the administration of anti-human IL-8R Ab, which blocks the function of mouse CXC chemokine(s). These findings reveal a critical role of mouse CXC chemokine(s) in Th1-dependent pulmonary neutrophilia and AHR.

[A case of nonresectable scirrhous type gastric cancer treated by hypertensive subselective chemotherapy with pharmacokinetic modulating chemotherapy]

There have been few effective chemotherapeutic regimens for scirrhous type gastric cancer. A 62-year-old male patient was admitted to our hospital because of anorexia and abdominal discomfort. Gastroendoscopy showed a type 4 advanced gastric cancer in the upper gastric body. Histologic study of biopsy specimens from the tumor revealed poorly differentiated adenocarcinoma. Examination by computed tomography and ultrasonography revealed swollen paraaortic lymph nodes and peritonitis carcinomatosa. The patient was diagnosed as having a nonresectable scirrhous type gastric cancer with peritonitis carcinomatosa and paraaortic lymph node metastasis. 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 the thoracic aorta. Furthermore, he was administered tegafur/uracil (400 mg/day) 5 days weekly as a pharmacokinetic modulating chemotherapy (PMC). After eight courses of treatment of PMC, paraaortic lymph node swelling and ascites decreased. This chemotherapy produced a partial response in the peritonitis carcinomatosa and paraaortic lymph nodes. This chemotherapy was repeated preoperatively. We reconsidered this case to show indications for operation. The patient died suddenly of acute heart failure before the operation. This therapy was considered an effective treatment for nonresectable gastric cancer.

Mechanical fluid flow enhances high-affinity-IgE-receptor-mediated secretion by mast cells adherent to fibronectin

We demonstrated the effect of interaction between mechanical fluid flow and the extracellular matrix on high-affinity-IgE-receptor (FcepsilonRI)-mediated secretion by mast cells (cell line MC/9). Mechanical fluid flow did not affect secretion by the cells in the absence of exogenou agonists. Mechanical fluid flow did not affect secretion by cells adherent tofibronectin in the absence of exogenous agonists, but it did enhance FcepsilonRI-mediated secretion by cells adherent tofibronectin. These finding indicate that fluid-flow-induced enhancement of secretion by mast cells requires both exogenous agonists and interaction between integrins and the extracellular matrix. The present study is thefirst to demonstrate that mechanical fluid flow enhances FcepsilonRI-mediated secretion by a mast cell line adherent tofibronectin.

Diagnosis of pancreatic adenocarcinoma by detection of human telomerase reverse transcriptase messenger RNA in pancreatic juice with sample qualification

PURPOSE

We evaluated the diagnostic efficacy of detection of human telomerase reverse transcriptase (hTERT) message, a catalytic domain of human telomerase, in endoscopic retrograde pancreatography (ERP)-derived pancreatic juice.

EXPERIMENTAL DESIGN

Both hTERT and CD25 expression were detected by reverse transcription-PCR (RT-PCR) in 17 patients with pancreatic adenocarcinoma (PC), 12 patients with chronic pancreatitis (CP), and 7 patients with no ERP abnormality (N). In the same patients, beta-actin message was semiquantified by competitive RT-PCR. K-ras codon 12 mutations were concomitantly analyzed by enriched PCR-SSCP in 11 and 7 PC and CP cases, respectively.

RESULTS

Expression of hTERT was detected in 88% of PC cases and 17% of CP cases but not in the normal control (N). Alterations in K-ras were detected in 73% of PC cases and 57% of CP cases, respectively. beta-Actin mRNA was expressed in >3.0 x 10(1) copies/microl in all but two PC cases in which hTERT mRNA was not detected. CD25-positive and -negative peripheral lymphocytes were isolated from a normal volunteer using a fluorescent activating cell sorter. The hTERT message was detected in CD25-positive peripheral lymphocytes and in 18, 25, and 0% of the pancreatic juice samples from PC, CP, and N cases, respectively. All CP cases expressing hTERT message were also CD25 positive.

CONCLUSIONS

These results suggest that detection of hTERT mRNA in pancreatic juice is a powerful tool to discriminate PC from CP, particularly when the samples are qualified against beta-actin mRNA levels and contaminating CD25-positive lymphocytes.

Mechanical fluid flow and surfactant-TA influence activation of macrophages

We examined the effect of mechanical fluid flow and surfactant on macrophage aggregation as the indication of macrophage activation. Mechanical fluid flow enhanced aggregation in phorbol myristate acetate (PMA)-treated human myeloid leukemic cell lines (HL-60 cells), but had no effect on differentiation of PMA-treated HL-60 cells. Surfactant-TA (an artificial surfactant) inhibited fluid flow-induced aggregation, but had no effect on differentiation of PMA-treated HL-60 cells. Human alveolar macrophages spontaneously formed small aggregates without stimulation. This aggregation was enhanced by fluid flow and inhibited by surfactant-TA. Taken together, these data suggest that macrophage activation is affected by fluid flow and surfactants.

[A case of successful management of nonresectable pancreas cancer with liver metastasis by intra-arterial infusion chemotherapy with angiotensin-II and administration of tegafur/uracil]

Nontypical chemotherapy regimens exist for advanced pancreatic cancer. We herein report a 62-year-old man whose nonresectable pancreatic cancer was treated effectively with a new method of intra-arterial regional chemotherapy with angiotensin-II (AT-II). The patient was admitted to our hospital with obstructive jaundice and anorexia. He was diagnosed as having inoperable advanced pancreatic cancer with liver metastasis. Enteric-coated tegafur/uracil (400 mg) was administered for 3 weeks. Simultaneously, intraarterial infusion with 5-fluorouracil (500 mg) and infusion of methotrexate (100 mg) with 50 micrograms of AT-II was given every week. A catheter connected to a subcutaneously implanted port system was placed into the common hepatic artery. As a result of this treatment, the maximum diameter of the pancreatic tumor decreased from 3 cm to 2 cm on the CT-scan. Serum carbohydrate antigen 19-9 (CA19-9) decreased from 24,000 U/ml to 186 U/ml. Moreover, the performance status of patient also improved, and he was discharged from our hospital despite his terminal cancer. This regimen could well be effective in cases of advanced pancreatic cancer.

Development of fulminant hepatitis B (precore variant mutant type) after the discontinuation of low-dose methotrexate therapy in a rheumatoid arthritis patient

A 75-year-old female rheumatoid arthritis patient who was positive for hepatitis B surface antigen and for antibodies to hepatitis Be antigen showed liver dysfunction, and therefore methotrexate (MTX) therapy was discontinued. Her drug lymphocyte stimulation test indicated positivity for MTX. Her liver dysfunction improved briefly, but she developed fulminant hepatitis with elevated levels of hepatitis B virus (HBV)/DNA polymerase and subsequently died. HBV/DNA analysis performed with polymerase chain reaction-mutation site-specific assay revealed that the fulminant hepatitis was caused by a precore mutant virus. Sudden reactivation of the immune system by discontinuation of MTX may have led to the attack on infected cells. Even when hepatitis Be antibodies are present, MTX should not be used in patients who have chronic infection with HBV.

Development of fulminant hepatitis B (precore variant mutant type) after the discontinuation of low-dose methotrexate therapy in a rheumatoid arthritis patient

A 75-year-old female rheumatoid arthritis patient who was positive for hepatitis B surface antigen and for antibodies to hepatitis Be antigen showed liver dysfunction, and therefore methotrexate (MTX) therapy was discontinued. Her drug lymphocyte stimulation test indicated positivity for MTX. Her liver dysfunction improved briefly, but she developed fulminant hepatitis with elevated levels of hepatitis B virus (HBV)/DNA polymerase and subsequently died. HBV/DNA analysis performed with polymerase chain reaction-mutation site-specific assay revealed that the fulminant hepatitis was caused by a precore mutant virus. Sudden reactivation of the immune system by discontinuation of MTX may have led to the attack on infected cells. Even when hepatitis Be antibodies are present, MTX should not be used in patients who have chronic infection with HBV.

Induction of Toll-like receptor 4 in granulocytic and monocytic cells differentiated from HL-60 cells

Toll-like receptor 4 (TLR4) is the main protein expressed on the cell surface and is an essential receptor for lipopolysaccharide (LPS) signalling in human peripheral blood leucocytes. We examined TLR4 expression and the functional response to LPS in retinoic acid-treated HL-60 cells (HL-60-derived granulocytic cells) and interferon-gamma-treated HL-60 cells (HL-60-derived monocytic cells). Slight TLR4 expression was induced in HL-60-derived granulocytic cells, while strong induction was seen in HL-60-derived monocytic cells. LPS induced interleukin 1beta (IL-1beta) production and TLR4 expression in HL-60-derived monocytic cells, but not HL-60-derived granulocytic cells. These data indicate different responses to LPS in the cells. TLR4 surface expression paralleled LPS-induced phagocytosis and TLR4-neutralizing antibody partially inhibited LPS-induced IL-8 production in HL-60-derived monocytic cells, but not in HL-60-derived granulocytic cells. These results suggest that HL-60-derived monocytic cells are partially activated via TLR4, but that HL-60-derived granulocytic cells are not activated via TLR4.

Development of fulminant hepatitis B (precore variant mutant type) after the discontinuation of low-dose methotrexate therapy in a rheumatoid arthritis patient

A 75-year-old female rheumatoid arthritis patient who was positive for hepatitis B surface antigen and for antibodies to hepatitis Be antigen showed liver dysfunction, and therefore methotrexate (MTX) therapy was discontinued. Her drug lymphocyte stimulation test indicated positivity for MTX. Her liver dysfunction improved briefly, but she developed fulminant hepatitis with elevated levels of hepatitis B virus (HBV)/DNA polymerase and subsequently died. HBV/DNA analysis performed with polymerase chain reaction-mutation site-specific assay revealed that the fulminant hepatitis was caused by a precore mutant virus. Sudden reactivation of the immune system by discontinuation of MTX may have led to the attack on infected cells. Even when hepatitis Be antibodies are present, MTX should not be used in patients who have chronic infection with HBV.

Diabetes mellitus with left transverse sinus thrombosis and right transverse sinus aplasia

A 67-year-old woman with diabetes mellitus was hospitalized due to a throbbing headache. She appeared neurologically normal, except for meningeal irritation. The cerebrospinal fluid pressure was high. There was increased fluid protein without an increased cell count. Brain CT scan showed no abnormality, however, brain magnetic resonance angiography (MRA) showed complete right transverse sinus stasis and partial left transverse sinus stasis, indicating bilateral transverse sinus thrombosis. At this time thrombin anti-thrombin III complex (TAT) and prothrombin fragment F1+2 (PTF1+2) indicating hypercoagulation had increased. Urokinase, followed by aspirin and ticlopidine hydrochloride were administered. After diet therapy and transient insulin administration, her blood glucose levels improved. By the 22nd day, the headache had disappeared. Subsequently, brain MRA showed left transverse sinus blood flow recovery and complete right transverse sinus stasis, while carotid angiography showed recovered left transverse sinus but right transverse sinus defect. TAT and PTF1+2 levels improved concomitantly with better blood glucose control. We diagnosed this case as left transverse sinus thrombosis because of the hypercoagulable state resulting from diabetes mellitus accompanied by right transverse sinus aplasia.

Quantitative evaluation of genomic instability as a possible predictor for development of hepatocellular carcinoma: comparison of loss of heterozygosity and replication error

Both loss of heterozygosity (LOH) and replication error (RER) are considered to be phenotypes of genomic instability. To unveil the role of the genomic instability in hepatocarcinogenesis, frequencies of LOH and RER were simultaneously determined in 15 hepatocellular carcinomas (HCCs), surrounding nontumorous liver tissues (SL), and 13 liver tissues with chronic viral hepatitis void of cancer (NC) by referencing peripheral blood leukocytes (PBLs) from the corresponding donor using 18 microsatellite markers spread throughout the genome. LOH was significantly frequent in HCC compared with that in SL or NC (P =.005, P =.0003, respectively) and observed preferentially at particular microsatellite loci, D1S204, D2S123, D8S1106, D9S266, D16S748, and D19S601. Although the higher prevalence of RER was also significant in HCC compared with that in NC (P =.03), in most cases the errors were detected at very low frequencies and random loci. Both LOH and RER tended to appear more prevalently in SL than in NC. The occurrence rate of LOH was higher in the tissues associated with hepatitis B virus (HBV) than with hepatitis C virus (HCV) infection especially in HCC (P =.03). When referencing SL instead of PBLs, the prevalence of LOH and RER in HCC significantly decreased (P =.02 and P =.03, respectively). These results suggest that LOH is closely associated with multistep hepatocarcinogenesis especially under HBV infection, but RER is imperceptibly associated. The quantitative evaluation of the frequency of LOH by referencing PBLs may be a useful predictor for HCC development in chronic liver diseases.

Plasma fucosyltransferase activity in patients with hepatocellular carcinoma, with special reference to correlation with fucosylated species of alpha-fetoprotein

BACKGROUND/AIMS

Our previous results showed that the percentage of fucosylated species of alpha-fetoprotein (AFP) in total AFP, fucosylation index, was a very useful diagnostic tool to distinguish AFP due to hepatocellular carcinoma from AFP due to non-neoplastic liver diseases. On the other hand, alpha1-6 fucosyl-transferase (alphaFT) catalyzes the addition of fucose from GDP-fucose through an alpha1-6 linkage to the reducing end of N-acetylglucosamine residue of N-linked oligosaccharides of glycoproteins. However, the biological and clinical significance of alphaFT in patients with hepatocellular carcinoma is not fully understood. In the present study, we measured alphaFT activity to elucidate the enzymatic background of fucosylated species of AFP in hepatocellular carcinoma.

METHODS

Plasma samples from 84 cases of hepatocellular carcinoma, 40 of liver cirrhosis, 40 of chronic hepatitis and 30 of normal controls, and 26 paired samples of hepatocellular carcinoma and surrounding noncancerous tissues were enrolled in the present study. AlphaFT activity was measured by high performance liquid chromatography with a synthesized fluorescence-labeled glycopeptide with an asialoagalactobiantennary sugar chain as a substrate in the presence of GDP-fucose.

RESULTS

Plasma alphaFT activities (mean+/-SD, pmol/ml/h) in patients with hepatocellular carcinoma, liver cirrhosis, chronic hepatitis and normal controls were 435+/-271, 490+/-290, 590+/-209 and 380+/-133, respectively. AlphaFT levels in hepatocellular carcinoma and chronic liver diseases were increased compared with that in normal controls. A statistically significant positive correlation was observed between plasma alphaFT activity and fucosylation index of AFP (r=0.34, p= 0.0032) in 60 patients with hepatocellular carcinoma, in which increments of serum AFP were observed. When the tentative cutoff value of fucosylation index was set at 18%, which corresponded to the cutoff value to discriminate between hepatocellular carcinoma and non-neoplastic liver diseases in our previous study, the plasma alphaFT activity in hepatocellular carcinoma patients whose fucosylation index was more than 18% (n=32, 523+/-324 pmol/ml/h) was higher than that in hepatocellular carcinoma patients whose fucosylation index was equal to or less than 18% (n=28, 383+/-229) (p=0.055). An increment of the plasma levels of alphaFT occurred in accordance with an advancement of hepatocellular carcinoma stages. Tissue aFT activity in hepatocellular carcinoma (175+/-178 pmol/mg/h) was higher than those in surrounding noncancerous liver (144+/-134) and in normal liver (79+/-19). The mean alphaFT activities in well-, moderately- and poorly-differentiated hepatocellular carcinoma were 38+/-0.7, 177+/-182 and 219+/-189, respectively, and they tended to increase with dedifferentiation in hepatocellular carcinoma tissues.

CONCLUSIONS

The present study indicates that alphaFT is responsible for the formation of the fucosylated species of AFP in hepatocellular carcinoma and suggests that the measurement of alphaFT provides a possible aid in the evaluation of the degree of advancement in patients with hepatocellular carcinoma.

Mycobacterium avium complex pleuritis accompanied by diabetes mellitus

A 72-year-old woman with diabetic nephropathy was hospitalized with peripheral edema in the extremities and weight increase. After diuretics and human serum albumin administration, her condition improved. From the 15th day she had run a subfever and her breathing was diminished in the left lower lung field. A plain chest X-ray film showed pleural effusion over the left lung field. The fluid was exudative. Fluid cultures were negative. A tuberculin reaction was negative. Polymerase chain reaction method disclosed mycobacterium avium complex, indicating rare pleuritis due to mycobacterium avium complex. Eighteen days after chemotherapy, pleural effusion disappeared. Although her hemoglobin A1c (HbA1c) levels were maintained from 6.0 to 6.5% over 4 years, urinary albumin excretion levels and serum creatinine levels increased, indicating deteriorating diabetic nephropathy. Serum albumin levels remained low (3.3-3.6 g/dl). Malnutrition, impaired cellular immunity and apparently abnormal microvascular circulation due to diabetes mellitus may consequently have induced pleuritis due to mycobacterium avium complex.

Decreased function of peripheral blood dendritic cells in patients with hepatocellular carcinoma with hepatitis B and C virus infection

BACKGROUND

Tumour immunity does not seem to be induced effectively in tumour-bearing hosts, including in patients with hepatocellular carcinoma (HCC). One possible reason is that function of dendritic cells (DC) is decreased in such hosts.

METHODS

We evaluated T cell stimulatory activity and interleukin (IL)-12 production of DC and interferon (IFN)-gamma and IL-10 production of T cells of peripheral blood from 12 control individuals and 21 patients with chronic hepatitis C virus (HCV) infection (six with chronic hepatitis (CH), eight with liver cirrhosis (LC) and 13 with HCC). Five hepatitis B virus (HBV)-infected patients with HCC were included as a disease control group. The DC were prepared by the culture of T cell-depleted populations of peripheral blood mononuclear cells in the presence of granulocyte-macrophage colony stimulating factor and IL-4 for a total of 11-12 days. The cytokine levels were assayed by ELISA. To test the stimulatory function of DC in T cell proliferation, mytomycin C-treated DC were cultured with allogeneic T cells from a control.

RESULTS

When the T cell-stimulatory activity of DC was expressed as stimulation index value of [3H]-thymidine incorporation of T cells, the values were lower in HCV-infected HCC (2.6 +/- 1.8, P < 0.01) than in controls (5.5 +/- 2.0) and CH (5.0 +/- 1.3). Staphylococcus aureus Cowan 1-induced IL-12 production of DC was decreased in HCV-infected HCC (P < 0.001, P < 0.01 and P < 0.05, respectively) compared with controls, CH and LC, while similar amounts of IL-10 were produced in patients and controls. Interleukin-10 and IFN-gamma production of T cells in response to anti-CD3 antibody or IL-12 were equivalent between patient groups and controls, respectively. Similarly decreased DC function and normal T cell response were observed in HBV-infected HCC patients.

CONCLUSIONS

These findings suggest that the depressed function of DC is associated with pathogenesis of HCC with HBV or HCV infection.

[The frequency profile of tuberculin skin testing among employees of a hospital]

The frequency profile of tuberculin skin testing among employees of a hospital was studied. In the analysis, tuberculin skin testing was defined as "negative" if skin rash is measured < or = 9 mm, and as "positive" if skin rash is measured > or = 10 mm, and as "strongly positive" if skin rash is measured > or = 10 mm, with induration, and double skin rash or bulla. Boosting was defined as initial skin rash was measured < or = 9 mm, with second skin rash measured > or = 10 mm and at least 6 mm increase of rash than the initial one. 544 employees were tested initially, and 81 were retested. Initial tuberculin positivity was associated with older age (p < 0.001); but boosting was not associated with age and occupation. Comparing pharmacists with other groups, the adjusted odds ratio of an initial strongly positive tuberculin reaction as significantly higher, namely 2.8 (95% confidence interval 1.2-6.7), but that of a booster reaction was 4.8 (0.7-32.1) which was insignificant.

[A case of pulmonary tuberculosis complicated with subcutaneous phaeohyphomycosis]

A 78-year-old male was admitted to our hospital because of fever, sputum and cough. Chest X-ray showed infiltrative shadows in the right lung field. Smears of his sputum were positive for acid-fast bacilli. We found multiple subcutaneous abscesses on the right distal forearm. Microscopic examination of skin biopsy specimens revealed granulation tissues with the proliferation of epitheloid cells with the scattering infiltrations of neurophils, giant cells and histiocytic cells. The examination of the PAS stained specimen revealed fungal elements and a black fungus, Exophiala jeanselmei, was isolated by the cultures of pus from the abscess. He was diagnosed as pulmonary tuberculosis complicated with subcutaneous phaeohyphomycosis caused by Exophiala jeanselmei and was successfully treated with anti-tuberculosis drugs and anti-fungal agent, 5-fluorocytosine.

[Lung cancer with chylothorax successfully treated by chemical pleurodesis with OK-432]

A 66-year-old man was admitted to our hospital because of bloody sputum. Chest computed tomographic scans disclosed a right hilar tumor. A tumor in the right upper-lobe bronchus was detected by fiberoptic bronchoscopy. Microscopic examination disclosed moderately differentiated squamous cell carcinoma. The patient was treated with irradiation and combination chemotherapy. Thereafter, right chylous pleural effusion developed and continued to accumulate. Pleurodesis was induced by the intrathoracic injection of OK-432 at 15 KE per dose. Lung cancer with nontraumatic chylothorax is rare. In our patient, pleurodesis with OK-432 was an effective treatment.

Reduction of telomeric repeats as a possible predictor for development of hepatocellular carcinoma: convenient evaluation by slot-blot analysis

Hepatocellular carcinoma (HCC) mainly arises from the liver with chronic inflammation. Because telomere reduction reflects replicative history in somatic cells, we analyzed the possibility that liver tissues surrounding HCC consist of the cells carrying substantial reduction of telomere. We studied 20 HCC and surrounding noncancerous liver tissues (SL) obtained by surgical resection, and 10 laparoscopically obtained needle biopsy specimens of the liver with chronic inflammation including no overt HCC (CI). Five liver tissues without chronic liver diseases (ND) were also examined. Extracted genomic DNAs were blotted on a nylon membrane, and probed at first with radio-labeled d(TTAGGG)(3) and reprobed with radio-labeled d(CCT)(7). The intensity caused by d(TTAGGG)(3) was divided by that of d(CCT)(7). The ratio was defined as telomeric repeats content (TC). Dilution experiments reproducibly revealed almost the same TC. The reduction rate of telomere length through aging estimated by regression analysis of TC was 0.62% per year. Concomitant analyses of TC and average telomere length revealed that both values were significantly correlated (r =.45; P =.009). To compare TC in the liver with respect to chronic inflammation, the value was divided by TC in peripheral blood leukocytes (PBL) from the same donor. The ratio was defined as relative TC (RTC). There was a statistically significant decrease of RTC in CI compared with that in ND (P =.03). Furthermore, RTC in SL was significantly lower than that in CI (P =.0001). These observations suggest that RTC value in liver tissues may digitally indicate a replicative history of hepatocytes under chronic inflammation, and a risk of HCC development.

[Diaphragmatic hernia with omental vessels delineated by computed tomography]

A 50-year-old man was admitted to our hospital for the evaluation of a blunted left costophrenic angle on chest roentgenograms. Chest non-enhanced computed tomographic (CT) scans demonstrated the omentum as a crescent-shaped, fat-dense, mass-like shadow on the left dorsal thoracic wall, contiguous with the abdominal cavity and floating. Omental vessels were recognized as funicular water densities running in the superior-to-inferior direction. Magnetic resonance imaging disclosed that the omental vessels ran continuously from the abdominal cavity into the thoracic cavity through a defect in the diaphragm. Diaphragmatic hernia was diagnosed, and corrective surgery performed. We reported this case because the CT-based delineation of omental vessels protruding into the thoracic cavity is rare.

The usefulness of determining des-gamma-carboxy prothrombin by sensitive enzyme immunoassay in the early diagnosis of patients with hepatocellular carcinoma

BACKGROUND

Measurements of serum concentrations of des-gamma-carboxy prothrombin (DCP) are widely used for diagnosing hepatocellular carcinoma (HCC). However, the DCP is not always sensitive enough to detect small HCCs. In the current study, the authors investigated the usefulness of DCP in the early diagnosis of HCC, using a more sensitive enzyme immunoassay than is conventionally employed.

METHODS

The authors examined 148 serum samples with DCP concentrations from a conventional assay of less than 100 mAU (arbitrary unit)/mL from 91 patients with HCC and 57 with cirrhosis. DCP concentrations were determined by a more sensitive enzyme immunoassay (ED-036 kit, Eisai Laboratory, Tokyo, Japan) with a minimal detection level of 10 mAU/mL. Ninety-one HCC patients had 43 solitary small HCCs (with a greatest dimension of less than 2 cm). Of these 43 HCCs, 12 were well differentiated.

RESULTS

The mean serum concentration of DCP in HCC (48.3 +/- 24.3, mean +/- standard deviation [SD]) was higher than in cirrhosis (20.3 +/- 10.3); this difference was statistically significant. When the tentative cutoff level of 40 mAU/mL (almost corresponding to the mean value + 2SD in patients with cirrhosis) was used as the level of discriminating HCC from cirrhosis, 62% of patients (56 of 91) with HCC had DCP values above this level (sensitivity). However, only three patients with cirrhosis had higher DCP levels. Thus, the specificity of this test was 95% (54 of 57 patients). The total accuracy was 74% (56 + 54/91 + 57). Twenty-three of 43 solitary small HCCs (53%) had DCP values above the cutoff level. Furthermore, 7 of 12 (58%) small, well-differentiated HCCs less than 2 cm in greatest dimension had higher DCP values.

CONCLUSIONS

The results of this study indicate that DCP determination by sensitive enzyme immunoassay is useful in the early diagnosis of HCC because a high specificity is maintained.

The usefulness of determining des-gamma-carboxy prothrombin by sensitive enzyme immunoassay in the early diagnosis of patients with hepatocellular carcinoma

BACKGROUND

Measurements of serum concentrations of des-gamma-carboxy prothrombin (DCP) are widely used for diagnosing hepatocellular carcinoma (HCC). However, the DCP is not always sensitive enough to detect small HCCs. In the current study, the authors investigated the usefulness of DCP in the early diagnosis of HCC, using a more sensitive enzyme immunoassay than is conventionally employed.

METHODS

The authors examined 148 serum samples with DCP concentrations from a conventional assay of less than 100 mAU (arbitrary unit)/mL from 91 patients with HCC and 57 with cirrhosis. DCP concentrations were determined by a more sensitive enzyme immunoassay (ED-036 kit, Eisai Laboratory, Tokyo, Japan) with a minimal detection level of 10 mAU/mL. Ninety-one HCC patients had 43 solitary small HCCs (with a greatest dimension of less than 2 cm). Of these 43 HCCs, 12 were well differentiated.

RESULTS

The mean serum concentration of DCP in HCC (48.3 +/- 24.3, mean +/- standard deviation [SD]) was higher than in cirrhosis (20.3 +/- 10.3); this difference was statistically significant. When the tentative cutoff level of 40 mAU/mL (almost corresponding to the mean value + 2SD in patients with cirrhosis) was used as the level of discriminating HCC from cirrhosis, 62% of patients (56 of 91) with HCC had DCP values above this level (sensitivity). However, only three patients with cirrhosis had higher DCP levels. Thus, the specificity of this test was 95% (54 of 57 patients). The total accuracy was 74% (56 + 54/91 + 57). Twenty-three of 43 solitary small HCCs (53%) had DCP values above the cutoff level. Furthermore, 7 of 12 (58%) small, well-differentiated HCCs less than 2 cm in greatest dimension had higher DCP values.

CONCLUSIONS

The results of this study indicate that DCP determination by sensitive enzyme immunoassay is useful in the early diagnosis of HCC because a high specificity is maintained.

The usefulness of determining des-gamma-carboxy prothrombin by sensitive enzyme immunoassay in the early diagnosis of patients with hepatocellular carcinoma

BACKGROUND

Measurements of serum concentrations of des-gamma-carboxy prothrombin (DCP) are widely used for diagnosing hepatocellular carcinoma (HCC). However, the DCP is not always sensitive enough to detect small HCCs. In the current study, the authors investigated the usefulness of DCP in the early diagnosis of HCC, using a more sensitive enzyme immunoassay than is conventionally employed.

METHODS

The authors examined 148 serum samples with DCP concentrations from a conventional assay of less than 100 mAU (arbitrary unit)/mL from 91 patients with HCC and 57 with cirrhosis. DCP concentrations were determined by a more sensitive enzyme immunoassay (ED-036 kit, Eisai Laboratory, Tokyo, Japan) with a minimal detection level of 10 mAU/mL. Ninety-one HCC patients had 43 solitary small HCCs (with a greatest dimension of less than 2 cm). Of these 43 HCCs, 12 were well differentiated.

RESULTS

The mean serum concentration of DCP in HCC (48.3 +/- 24.3, mean +/- standard deviation [SD]) was higher than in cirrhosis (20.3 +/- 10.3); this difference was statistically significant. When the tentative cutoff level of 40 mAU/mL (almost corresponding to the mean value + 2SD in patients with cirrhosis) was used as the level of discriminating HCC from cirrhosis, 62% of patients (56 of 91) with HCC had DCP values above this level (sensitivity). However, only three patients with cirrhosis had higher DCP levels. Thus, the specificity of this test was 95% (54 of 57 patients). The total accuracy was 74% (56 + 54/91 + 57). Twenty-three of 43 solitary small HCCs (53%) had DCP values above the cutoff level. Furthermore, 7 of 12 (58%) small, well-differentiated HCCs less than 2 cm in greatest dimension had higher DCP values.

CONCLUSIONS

The results of this study indicate that DCP determination by sensitive enzyme immunoassay is useful in the early diagnosis of HCC because a high specificity is maintained.

[Malignant hemangioendothelioma associated with chronic pyothorax]

A 67-year-old man was admitted to the hospital because of a fever. A chest CT scan showed multilobular heterogeneous shadows on the right side in the chest wall and the lung, but clinical examinations and examination of a biopsy specimen did not lead to a diagnosis. At autopsy, a hemorrhagic tumor was found on the right side in the chest wall. Microscopical examination showed that large atypical cells had proliferated and formed vascular structures, which were stained positively with anti-factor VIII antibody. The histological findings led to the diagnosis of malignant hemangioendothelioma. Chronic empyema-associated malignant hemangioendothelioma is rare.

[Removal of bronchial foreign bodies by suction with a bronchoscope]

We report two cases in which intrabronchial foreign bodies were removed with a fiberoptic bronchoscope. In both cases the foreign body was a seed of a small Japanese apricot. Atelectasis or obstructive pneumonia was seen on chest roentgenograms. The foreign bodies were associated with slight inflammation and polyps on the bronchial epithelium. The foreign bodies were removed by applying suction with a fiberoptic bronchoscope. This method may also be useful for removing other large, hard, uneven, and ball-like foreign bodies.

Clinical significance of simultaneous determinations of alpha-fetoprotein and des-gamma-carboxy prothrombin in monitoring recurrence in patients with hepatocellular carcinoma

BACKGROUND

Measurements of serum alpha-fetoprotein (AFP) concentration and plasma concentration of des-gamma-carboxy prothrombin (DCP) have been widely used for the early diagnosis of hepatocellular carcinoma (HCC). The two markers generally run parallel to each other. However, in our study, they sometimes fluctuated independently in response to tumor regression or recurrence.

METHODS

A longitudinal series of concentrations of serum AFP and plasma DCP were determined simultaneously for 245 patients with HCC from the time of diagnosis to tumor recurrence after treatment.

RESULTS

Positive reactions for AFP were noted in 168 patients (69%) and for DCP in 126 patients (51%). One hundred and ten of 245 patients with HCC (45%) were positive for both AFP and DCP. In 35 patients (14%), these 2 tumor markers fluctuated independently in response to tumor regression and recurrence. These patients were categorized into four groups as follows: Group 1 had elevated AFP only at diagnosis; it then decreased after treatment, but DCP was elevated at the time of tumor recurrence without AFP elevation (3 patients); Group 2 had elevated DCP at diagnosis and elevated AFP at tumor recurrence (4 patients); Group 3 had elevated AFP and DCP at diagnosis, but only AFP (8 patients) or DCP (7 patients) was elevated at tumor recurrence; Group 4 had only elevated AFP (2 patients) or DCP (11 patients) at diagnosis, but both AFP and DCP were elevated at tumor recurrence.

CONCLUSIONS

The results of this study indicate that simultaneous determinations of AFP and DCP are useful for monitoring recurrence in patients with HCC after treatment, and that the decrease to normal levels of a single marker does not always indicate the absence of tumor recurrence.

Clinical significance of simultaneous determinations of alpha-fetoprotein and des-gamma-carboxy prothrombin in monitoring recurrence in patients with hepatocellular carcinoma

BACKGROUND

Measurements of serum alpha-fetoprotein (AFP) concentration and plasma concentration of des-gamma-carboxy prothrombin (DCP) have been widely used for the early diagnosis of hepatocellular carcinoma (HCC). The two markers generally run parallel to each other. However, in our study, they sometimes fluctuated independently in response to tumor regression or recurrence.

METHODS

A longitudinal series of concentrations of serum AFP and plasma DCP were determined simultaneously for 245 patients with HCC from the time of diagnosis to tumor recurrence after treatment.

RESULTS

Positive reactions for AFP were noted in 168 patients (69%) and for DCP in 126 patients (51%). One hundred and ten of 245 patients with HCC (45%) were positive for both AFP and DCP. In 35 patients (14%), these 2 tumor markers fluctuated independently in response to tumor regression and recurrence. These patients were categorized into four groups as follows: Group 1 had elevated AFP only at diagnosis; it then decreased after treatment, but DCP was elevated at the time of tumor recurrence without AFP elevation (3 patients); Group 2 had elevated DCP at diagnosis and elevated AFP at tumor recurrence (4 patients); Group 3 had elevated AFP and DCP at diagnosis, but only AFP (8 patients) or DCP (7 patients) was elevated at tumor recurrence; Group 4 had only elevated AFP (2 patients) or DCP (11 patients) at diagnosis, but both AFP and DCP were elevated at tumor recurrence.

CONCLUSIONS

The results of this study indicate that simultaneous determinations of AFP and DCP are useful for monitoring recurrence in patients with HCC after treatment, and that the decrease to normal levels of a single marker does not always indicate the absence of tumor recurrence.

Induction of muscarinic receptor subtypes in monocytic/macrophagic cells differentiated from EoL-1 cells

We demonstrated that eosinophilic leukemia cell line-1 (EoL-1 cells) differentiated into monocytic/macrophagic cells by a treatment with interferon-gamma. Muscarinic receptor mRNA was not detected in untreated EoL-1 cells, and the cytosolic concentration of Ca2+ ([Ca2+]i) did not rise either in these cells. Interestingly, when EoL-1 cells were treated with interferon-gamma, mRNAs for muscarinic M3 and M5 receptors could be detected in these cells, along with an increase in [Ca2+]i and chemotaxis induced by carbachol that could be blocked with 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) and pirenzepine. These data support the functional importance of muscarinic M3 and M5 receptors in monocytic/macrophagic cells differentiated from EoL-1 cells. This model also provides evidence of a significant functional interaction between muscarinic M3 and M5 receptors.

Utility of 3-O-methyl-N-acetyl-D-glucosamine, an N-acetylglucosamine kinase inhibitor, for accurate assay of glucokinase in pancreatic islets and liver

Glucokinase, an enzyme that catalyzes the phosphorylation of glucose, constitutes the key regulatory step in glucose metabolism in pancreatic islets and liver. We found that 3-O-methyl-N-acetyl-D-glucosamine (3-O-methyl-GlcNAc) potently inhibits glucose phosphorylation by N-acetylglucosamine kinase whereas glucokinase is not at all affected by this hexosamine. The addition of 3-O-methyl-GlcNAc to the assay system for glucokinase in rat liver extracts, which contain a high activity of glucokinase (glucose as substrate) relative to N-acetylglucosamine kinase (N-acetyl-D-glucosamine as substrate), affected neither Km nor Vmax values of glucokinase. On the other hand, both Km and Vmax values of glucokinase in rat pancreatic islet extracts, in which N-acetylglucosamine kinase activity is higher than glucokinase activity, were significantly lowered by the use of 3-O-methyl-GlcNAc as an inhibitor of N-acetylglucosamine kinase.