Associations of PD-L1, PD-L2, and HLA class I expression with responses to immunotherapy in patients with advanced sarcoma: post hoc analysis of a phase 1/2 trial

BACKGROUND

Although immunotherapy is thought to be a promising cancer treatment, most patients do not respond to immunotherapy. In this post hoc analysis of a phase 1/2 study, associations of programmed death ligand 1 (PD-L1), PD-L2, and HLA class I expressions with responses to dendritic cells (DCs)-based immunotherapy were investigated in patients with advanced sarcoma.

METHODS

This study enrolled 35 patients with metastatic and/or recurrent sarcomas who underwent DC-based immunotherapy. The associations of PD-L1, PD-L2, and HLA class I expressions in tumor specimens, which were resected before immunotherapy, with immune responses (increases of IFN-γ and IL-12) and oncological outcomes were evaluated.

RESULTS

Patients who were PD-L2 (+) showed lower increases of IFN-γ and IL-12 after DC-based immunotherapy than patients who were PD-L2 (-). The disease control (partial response or stable disease) rates of patients who were PD-L1 (+) and PD-L1 (-) were 0% and 22%, respectively. Disease control rates of patients who were PD-L2 (+) and PD-L2 (-) were 13% and 22%, respectively. Patients who were PD-L1 (+) tumors had significantly poorer overall survival compared with patients who were PD-L1 (-). No associations of HLA class I expression with the immune response or oncological outcomes were observed.

CONCLUSIONS

This study suggests that PD-L1 and PD-L2 are promising biomarkers of DC-based immunotherapy, and that addition of immune checkpoint inhibitors to DC-based immunotherapy may improve the outcomes of DC-based immunotherapy.

Polymersome formation induced by encapsulation of water-insoluble molecules within ABC triblock terpolymers

We found a morphological transition from spherical micelles to polymersomes induced by encapsulation of hydrophobic guest molecules.

Unraveling the kinetics of the structural development during polymerization-induced self-assembly: decoupling the polymerization and the micelle structure

Upon extending a hydrophobic polymer chain from the end of a preceding hydrophilic chain in aqueous solutions, the resultant block copolymers may eventually undergo self-assembly.

Realization of Spin-dependent Functionality by Covering a Metal Surface with a Single Layer of Molecules

An interface of molecule and metal has attracted much attention in the research field of nanoelectronics because of their high degree of design freedom. Here, we demonstrate an efficient spin-to-charge current conversion at the metal surface covered by a single layer of molecules. Spin currents are injected into an interface between metal (Cu) and lead(II) phthalocyanine by means of the spin pumping method. An observed voltage signal is caused by the inverse Edelstein effect, i.e., spin-to-charge current conversion at the interface. The conversion coefficient, inverse Edelstein length, is estimated to be 0.40 ± 0.06 nm, comparable with the largest Rashba spin splitting of interfaces with heavy metals. Interestingly, the Edelstein length strongly depends on the thickness of the molecule and takes a maximum value when a single layer of molecules is formed on the Cu surface. Comparative analysis between scanning probe microscopy and first-principles calculations reveal that the formation of interface state with Rashba spin splitting causes the inverse Edelstein effect, whose magnitude is sensitive to the adsorption configuration of the molecules.

Core-Shell-Corona Micelles from a Polyether-Based Triblock Terpolymer: Investigation of the pH-Dependent Micellar Structure

Core-shell-corona micelles featuring a pH-responsive shell have been characterized in dilute aqueous solution at different pH values (4-8) by using dynamic light scattering (DLS), field-flow fractionation coupled with multiangle light scattering detector (FFF-MALS), steady-state fluorescence, small-angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). The micelles are formed by self-assembly of a polyether-based triblock terpolymer consisting of a hydrophobic poly( tert-butyl glycidyl ether) block (P tBGE), a pH-responsive modified poly(allyl glycidyl ether) segment (PAGE_COOH), and a neutral hydrophilic poly(ethylene oxide) block (PEO). Because of the side-chain carboxylic acids in the middle block, the micellar structure and size depends on the solution pH. Hereby, we show that an increase in pH induces a decrease in the aggregation number ( N_agg). In addition, the combination of the above measurements revealed an unexpected morphological change from spherical to ellipsoidal micelles by increasing pH.

Pathogenesis of acute and chronic diseases caused by cyprinid herpesvirus-3

The pathogenesis of cyprinid herpesvirus-3 (CyHV-3) was studied using different lineages of carp/koi. After exposure to the virus, infected cells were first found in the skin by histopathology and by in situ hybridization. The epidermis of the skin was most severely damaged and often sloughed off in the fish sampled on days 5 through 8, and the fish that were highly sensitive to the virus died within 8 or 10 days after infection. Serum osmolality of the infected fish, particularly just before death, was significantly lower, suggesting that the osmotic shock consequent on the damage to the skin was the direct cause of the acute deaths. On the other hand, clinical and histopathological observations indicate that the carp of a less sensitive lineage most probably died of viral encephalitis around 3 weeks after infection. For these fish, the largest number of infected cells was found in the central nervous system (CNS) sampled on day 12. A substantial amount of viral genome was found in the CNS of carp surviving more than 1 year after the infection. Thus, the CNS is probably a major target for CyHV-3, and the virus can persistently infect the CNS, presumably establishing latency.

Indoleamine 2,3-dioxygenase in the pathogenesis of tuberculous pleurisy

BACKGROUND

Pleural fluid is a frequent manifestation in pulmonary diseases, such as lung cancer and infectious diseases, including pulmonary tuberculosis (TB). The enzyme indoleamine 2,3-dioxygenase (IDO) catalyses tryptophan through the kynurenine pathway, and is considered a crucial immunoregulatory molecule mediating immune tolerance. Recent studies have shown IDO activity to be a novel prognostic factor not only in cancer patients but also in those with infectious diseases, including pneumonia and pulmonary TB. However, no studies have measured and determined the clinical significance of IDO activity in pleural fluid.

METHODS

We enrolled 92 patients, including 34 with tuberculous pleurisy (TBP), 36 with malignant pleuritis and 15 with parapneumonic effusions. IDO activity was evaluated using liquid chromatography/electrospray ionisation tandem mass spectrometry, and was estimated by calculating kynurenine-to-tryptophan ratio.

RESULTS

Pleural fluid from patients with TBP had significantly higher kynurenine concentrations and significantly lower tryptophan concentrations, resulting in significantly higher IDO activity compared with pleural effusion or serum from non-tuberculous pleuritis (all P < 0.001). Pleural tissue from TBP showed enhanced IDO expression in epithelioid granuloma regions by immunohistochemistry.

CONCLUSIONS

These results suggest that IDO is strongly involved in the pathogenesis of TBP.

Highly sensitive nanoscale spin-torque diode

Highly sensitive microwave devices that are operational at room temperature are important for high-speed multiplex telecommunications. Quantum devices such as superconducting bolometers possess high performance but work only at low temperature. On the other hand, semiconductor devices, although enabling high-speed operation at room temperature, have poor signal-to-noise ratios. In this regard, the demonstration of a diode based on spin-torque-induced ferromagnetic resonance between nanomagnets represented a promising development, even though the rectification output was too small for applications (1.4 mV mW(-1)). Here we show that by applying d.c. bias currents to nanomagnets while precisely controlling their magnetization-potential profiles, a much greater radiofrequency detection sensitivity of 12,000 mV mW(-1) is achievable at room temperature, exceeding that of semiconductor diode detectors (3,800 mV mW(-1)). Theoretical analysis reveals essential roles for nonlinear ferromagnetic resonance, which enhances the signal-to-noise ratio even at room temperature as the size of the magnets decreases.

Encephalomyelitis associated with microsporidian infection in farmed greater amberjack, Seriola dumerili (Risso)

An outbreak of a disease characterized by a peculiar spiral movement in farmed greater amberjack, Seriola dumerili (Risso), occurred in Kagoshima Prefecture, Japan, in May 2008, immediately after importing the fish from China. Although neither bacteria nor viruses were detected in routine diagnostic tests, histopathological observations of the affected fish revealed severe inflammation in the tegmentum of the brain including the medulla oblongata and the anterior part of the spinal cord. In addition, a microsporidian parasite was observed in the nerve cell bodies or axons in the inflamed tissues. We identified a microsporidian small subunit rRNA gene (SSU rDNA) from the lesion, and the sequence showed 96.1% identity with that of Spraguea lophii. Subsequent in situ hybridization using probes presumably specific to the SSU rRNA confirmed that the parasite observed in histopathology harboured the identified SSU rRNA. Apparently degenerated microsporidian cells or spores were also frequently observed in tissue sections. Thus, the disease was most probably caused by the infection of a hitherto unknown microsporidian parasite that has a genetic affinity to the genus Spraguea, in the central nervous system of the amberjack.

Usefulness of serum procalcitonin levels in pulmonary tuberculosis

There are very few data on serum procalcitonin (PCT) levels in pulmonary tuberculosis (PTB) patients who are negative for HIV. We assessed serum PCT in consecutive patients diagnosed with pulmonary tuberculosis or community-acquired pneumonia (CAP) on admission to discriminate between PTB and CAP, and examined the value of prognostic factors in PTB. 102 PTB patients, 62 CAP patients, and 34 healthy volunteers were enrolled. Serum PCT in PTB patients was significantly lower than in CAP patients (mean ± sd 0.21 ± 0.49 versus 4.10 ± 8.68 ng·mL⁻¹; p < 0.0001). By receiver-operating characteristic curve analysis, serum PCT was an appropriate discrimination marker for PTB and CAP (area under the curve 0.866). PTB patients with ≥ 0.5 ng·mL⁻¹ (normal cut-off) had significantly shorter survival than those with < 0.5 ng·mL⁻¹ (p < 0.0001). Serum PCT is not habitually elevated in HIV-negative PTB patients and is a useful biomarker for discriminating between PTB and CAP; however, when serum PCT is outside the normal range, it is a poor prognostic marker.

Disease recurrence patterns after R0 resection of hilar cholangiocarcinoma

BACKGROUND

There is little information regarding the clinical behaviour of hilar cholangiocarcinoma after curative resection.

METHODS

A retrospective study was undertaken of 79 consecutive patients with hilar cholangiocarcinoma who had undergone major hepatectomy (three or more Couinaud segments) concomitant with caudate lobectomy, and had negative resection margins. Sites of initial disease recurrence were classified as locoregional (porta hepatis) or distant (intrahepatic, peritoneal, para-aortic lymph nodal or extra-abdominal). Univariable and multivariable analyses were performed to determine the factors potentially related to recurrence.

RESULTS

Disease recurrence was observed in 42 (53 per cent) of the 79 patients. Cumulative recurrence rates at 3 and 4 years after surgery were 52 and 56 per cent respectively. Locoregional recurrence alone was observed in eight (10 per cent) and distant metastasis in 34 (43 per cent) of the 79 patients after R0 resection. Positive nodal involvement and high International Union Against Cancer tumour (T) stage were independent prognostic factors associated with distant metastasis.

CONCLUSION

Distant metastases are more common than locoregional recurrence after R0 resection for hilar cholangiocarcinoma, and associated with nodal involvement and high T stage.

Histopathology of Antarctic krill, Euphausia superba, bearing black spots

Small black spots have been noticed on the cephalothorax of Antarctic krill, Euphausia superba, since January, 2001. To study the nature of the black spots, the krill were sampled in the winter of 2003, 2006, and 2007 in the South Georgia region, the Antarctic Ocean. Histological observations revealed that the black spots were melanized nodules that were composed of hemocytes surrounding either bacteria or amorphous material. In the 2007 samples, 42% of the krill had melanized nodules. Most of the nodules had an opening on the body surface of the krill. A single melanized nodule often contained more than one type of morphologically distinct bacterial cell. Three bacteria were isolated from these black spots, and classified into either Psychrobacter or Pseudoalteromonas based on the sequences of 16S rRNA genes. More than three bacterial species or strains were also confirmed by in situ hybridization for 16S rRNA. The melanized nodules were almost always accompanied by a mass of atypical, large heteromorphic cells, which were not observed in apparently healthy krill. Unidentified parasites were observed in some of the krill that had melanized nodules. These parasites were directly surrounded by the large heteromorphic cells. Histological observations suggested that these heteromorphic cells were attacking the parasites. These results suggest the possibility that the krill had been initially affected by parasite infections, and the parasitized spots were secondary infected by environmental bacteria after the parasites had escaped from the host body.

Morphogenesis of koi herpesvirus observed by electron microscopy

Koi herpesvirus (KHV or cyprinid herpesvirus 3) was inoculated onto three fish cell lines derived from carp, Cyprinus carpio L., and the process of virion formation observed with electron microscopy. Essentially, similar features of virus particles were observed in all three cell lines. The nucleus of infected cells was characterized by margination of chromatin and often contained many capsids of about 110 nm in diameter with varying morphology. The morphological variation of the capsids was very similar to that of mammalian herpesviruses. Some capsids protruded from the inner nuclear membrane, and others, with envelopes, were located in the perinuclear space between the inner and outer nuclear membrane, suggesting budding of capsids at the inner nuclear membrane. Naked capsids and envelopment of capsids by budding into vesicles were also observed in the cytoplasm. Mature, enveloped virions 170-200 nm in diameter were seen in cytoplasmic vesicles or outside the cell. These observations suggest KHV virions mature through a complex morphological pathway including two distinct envelopments, which have been found only in herpesviruses. These observations support the inclusion of KHV in the family Herpesviridae.

Upregulated EMMPRIN/CD147 might contribute to growth and angiogenesis of gastric carcinoma: a good marker for local invasion and prognosis

Tumour growth depends on angiogenesis, which is closely associated with vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). Extracellular MMP inducer (EMMPRIN) was reported to involve in the progression of malignancies by regulating expression of VEGF and MMPs in stromal cells. To clarify the role of EMMPRIN in progression and angiogenesis of gastric carcinoma, expression of EMMPRIN, ki-67, MMP-2, MMP-9 and VEGF was examined on tissue microarray containing gastric carcinomas (n=234) and non-cancerous mucosa adjacent to carcinoma (n=85) by immunohistochemistry. Additionally, microvessel density (MVD) was assessed after labelling with anti-CD34 antibody. Extracellular MMP inducer expression was compared with clinicopathological parameters of tumours, including levels of ki-67, MMP-2, MMP-9 and vascular endothelial growth factor (VEGF), MVD as well as survival time of carcinoma patients. Gastric carcinoma cell lines (HGC-27, MKN28 and MKN45) were studied for EMMPRIN expression by immunohistochemistry and Western blot. Extracellular MMP inducer expression was gradually increased from normal mucosa to carcinomas through hyperplastic or metaplastic mucosa of the stomach (P<0.05). There was strong EMMPRIN expression in all gastric carcinoma cell lines despite different levels of glycosylation. Extracellular MMP inducer expression was positively correlated with tumour size, depth of invasion, lymphatic invasion, expression of ki-67, MMP-2, MMP-9 and VEGF of tumours (P<0.05), but not with lymph node metastasis, UICC staging or differentiation (P>0.05). Interestingly, there was a significantly positive relationship between EMMPRIN expression and MVD in gastric carcinomas (P<0.05). Survival analysis indicated EMMPRIN expression to be negatively linked to favourable prognosis (P<0.05), but not be independent factor for prognosis (P>0.05). Further analysis showed three independent prognostic factors, depth of invasion, lymphatic and venous invasion, to influence the relationship between EMMPRIN expression and prognosis. Upregulated expression of EMMPRIN possibly contributes to genesis, growth and local invasion of gastric carcinomas. Altered EMMPRIN expression might enhance growth, invasion and angiogenesis of gastric carcinoma via upregulating MMP expression of both stromal fibroblasts and gastric cancer cells and could be considered as an objective and effective marker to predict invasion and prognosis.

[Isolated coronary artery bypass grafting in octogenarians]

We evaluate the outcomes of isolated coronary artery bypass grafting (CABG) in high-risk octogenarians. There are 20 cases in 5 years, which contain 1 re-operation case, and 10 emergency cases. Nineteen cases were performed off-pump CABG (OPCAB), and conventional CABG was performed for only 1 case because of unstable hemodynamics with intraaortic balloon pumping (IABP). We generally performed CABG with aorta no-touch technique. There is no death case, and no serious complication like stroke. We used 23 artery and 11 vein grafts for CABG, and mean number of grafts per patient was 1.8+/-0.7. And "hybrid therapy" with percutaneous transluminal coronary angioplasty (PTCA) was done for 5 cases. Octogenarians are at increased risk for perioperative morbidity and mortality after CABG, but we have performed OPCAB for them and have had good results. And we think that aorta no-touch technique, proper selection and use of graft are important.

Mitochondrial matrix reactive oxygen species production is very sensitive to mild uncoupling

Mitochondria produce ROS (reactive oxygen species) as a by-product of aerobic respiration. Several studies in mammals and birds suggest that the most physiologically relevant ROS production is from complex I following reverse electron flow, and is highly sensitive to membrane potential. A study of Drosophila mitochondria respiring glycerol 3-phosphate revealed that membrane potential-sensitive ROS production from complex I following reverse electron flow was on the matrix side of the inner membrane. A 10 mV decrease in membrane potential was enough to abolish around 70% of the ROS produced by complex I under these conditions. Another important ROS generator in this model, glycerol-3-phosphate dehydrogenase, produced ROS mostly to the cytosolic side; this ROS production was totally insensitive to a small decrease in membrane potential (10 mV). Thus mild uncoupling may be particularly significant for ROS production from complex I on the matrix side of the mitochondrial inner membrane.

Ca(2+) influx through nonselective cation channels plays an essential role in noradrenaline-induced arachidonic acid release in Chinese hamster ovary cells expressing alpha(1A)-, alpha(1B)-, or alpha(1D)-adrenergic receptors

We constructed Chinese hamster ovary (CHO) cells stably expressing alpha(1A)-, alpha(1B)-, or alpha(1D)-adrenergic receptors (CHO-alpha(1A), CHO-alpha(1B), or CHO-alpha(1D), respectively) and compared the Ca(2+) channels activated by noradrenaline (NA) in these cells using whole-cell recordings and monitoring of the intracellular free Ca(2+) concentration ([Ca(2+)](i)). We also investigated the involvement of Ca(2+) channels in the NA-induced arachidonic acid release. In all three cell types, NA at concentrations > or =10 nM induced a sustained increase in [Ca(2+)](i) attributable to extracellular Ca(2+) influx in [Ca(2+)](i) monitoring and an inward current in whole-cell recording. The current-voltage relationships were linear, and their reversal potentials were close to 0 mV. The reversal potential of the currents was not affected by a change in the concentration of Cl(-) in the bath solution. Moreover, a current could be induced in a bath solution containing only Ca(2+) as the movable cation. LOE 908, a receptor-operated Ca(2+) channel blocker, inhibited the sustained increase in [Ca(2+)](i) and inward currents in a concentration-dependent manner, and complete inhibition was observed at concentrations > or = 3 microM. NA induced arachidonic acid release in all three cell types. This release was entirely dependent on extracellular Ca(2+) influx. Moreover, LOE 908 at concentrations > or = 3 microM blocked the NA-induced increase in arachidonic acid release. These results indicate that 1) NA activates LOE 908-sensitive Ca(2+)-permeable nonselective cation channels (NSCCs) in CHO-alpha(1A), CHO-alpha(1B), and CHO-alpha(1D), and 2) the Ca(2+) influx through NSCCs may play an important role in the NA-induced enhancement of arachidonic acid release in these cells.

[Field epidemiological investigation on an outbreak of Chlamydia pneumoniae infection--first recognized incidence in a nursing home for elderly in Japan]

Chlamydia pneumoniae (C. pneumoniae) is an emerging pathogen recognized in 1989. Although C. pneumoniae infection is known to give a great impact on public health in western countries, many aspects remain unclarified in Japan. During December 1999 and March 2000, respiratory symptoms among residents and employees in a nursing home for elderly implicated an outbreak of C. pneumoniae infection. Field epidemiological investigation confirmed that this is the first outbreak recognized in a nursing home setting in Japan, involving 31/59 (15 confirmed) residents and 9/41 (2 confirmed) employees. Fifteen residents developed severe C. pneumoniae infections including one fatal outcome with pneumonia. Epidemiological analysis did not identify risk factors which induce infection or severe illness by C. pneumoniae for the residents. However, for the employees, frequent contact with the residents was demonstrated as a significant risk factor for the infection. None of 13 employees who had no contact with the residents presented C. pneumoniae infection, while nine out of 28 employees who had frequent contact developed C. pneumoniae infections (RR infinite, P = 0.04). These results indicated that C. pneumoniae infection spread gradually by human-to-human droplet transmission without specific risk factors. This study raised current problems in diagnosing and treating the C. pneumoniae infection and the need to enhance the awareness of this disease.

Transitional cell carcinoma of the renal pelvis in a long-term hemodialysis patient with autosomal dominant polycystic kidney

We present a case of renal pelvic transitional cell carcinoma (TCC) accompanied by autosomal dominant polycystic kidney disease (ADPKD). An 81-year-old woman on long-term hemodialysis for ADPKD visited the Department of Urology at Kouseiren Takaoko Hospital, complaining of asymptomatic macroscopic hematuria. Retrograde pyelogram showed an irregular filling defect in the right renal pelvis, which suggested the right renal pelvic tumor. We performed right nephrectomy and transurethral removal of the right ureter. Histological diagnosis demonstrated renal pelvic TCC.

Initial effects of the left ventricular repair by plication may not last long in a rat ischemic cardiomyopathy model

BACKGROUND

Long term effects of left ventricle (LV) repair surgery (LVR) for ischemic cardiomyopathy are not well understood.

METHODS AND RESULTS

Sixty-nine rats developed ischemic cardiomyopathy with large akinetic LV area 4 weeks after the left anterior descending artery was ligated. In a second surgery 4 weeks later, 33 rats underwent LVR by plication of the akinetic LV area (LVR group), and 36 underwent rethoracotomy alone (sham group). No medication was used in either group. All rats survived the second surgery. LV end-diastolic dimension as measured by echocardiography, LV fractional shortening, and the maximal end-systolic pressure-volume relationship (E(max)) as calculated from the data by catheter-tipped manometer and echocardiography improved in the LVR group after the second surgery, but LV end-diastolic dimension and E(max) gradually deteriorated as time passed. LV end-diastolic pressure improved 1 week after LVR but rose significantly 4 weeks after LVR. Brain natriuretic peptide mRNA was lower in the LVR group than in the sham group 1 week after LVR but not 4 weeks postoperatively.

CONCLUSIONS

Initial improvement in LV function and neurohormonal status after LVR did not last for 4 weeks in this rat model when untreated medically. The mechanism of deterioration should be elucidated to improve long-term results of LVR.

Multi-layer amniotic membrane graft for pterygium in a patient with xeroderma pigmentosum

BACKGROUND

Xeroderma pigmentosum (XP) is a rare, autosomal recessive, premalignant condition of the skin, and is reported to be associated with ocular surface disorders such as conjunctival malignancy and pterygium. Herein, we report a case of successful management of pterygium with multi-layer amniotic membrane graft (AMG) in a young XP patient.

CASE

An 11-year-old Japanese girl, who had been diagnosed as having XP, was referred to us for treatment of her bilateral pterygium. Surgical intervention was attempted for a temporal, presumably fast-growing pterygium in her left eye. Multi-layer amniotic membrane grafting was performed.

OBSERVATIONS

The surgery-induced pain and irritation disappeared within a day. The limbal conjunctival autograft survived on the AMG and re-epithelialization over the AMG was completed in 2 weeks. Best corrected visual acuity improved from 20/32 to 20/16 one month postoperatively. During the 1-year follow-up period, no recurrence was noted.

CONCLUSIONS

The present case exemplifies that AMG as an adjunct to primary pterygium resection is effective even in a young patient with XP. In addition, multi-layer AMG, which we first demonstrated in this report, seems to be useful for protecting bare sclera and extraocular muscles from mechanical injury.

A new glucose-6-phosphate dehydrogenase variant G6PD Sugao (826C-->T) exhibiting chronic hemolytic anemia with episodes of hemolytic crisis immediately after birth

A case of glucose-6-phosphate dehydrogenase (G6PD) deficiency associated with chronic hemolysis with episodes of hemolytic crisis immediately after birth is reported. The propositus was a 1-month-old Japanese male infant. Molecular analysis of the G6PD gene revealed a novel missense mutation (826C-->4T) in exon 8 predicting a single amino acid substitution, Pro276Ser. The mother was confirmed to be heterozygous for this mutation. We designated this novel class 1 variant as G6PD Sugao. Pro276 is a phylogenetically conserved residue that may play a significant role in dimer formation.

Value of lipiodol computed tomography and digital subtraction angiography in the era of helical biphasic computed tomography as preoperative assessment of hepatocellular carcinoma

OBJECTIVE

To compare the diagnostic accuracies of Lipiodol computed tomography (CT) and helical biphasic CT as preoperative imaging modalities for hepatocellular carcinoma (HCC).

SUMMARY BACKGROUND DATA

Lipiodol CT after digital subtraction angiography has long been used as a highly sensitive imaging modality for HCC. The recent advent of helical CT has allowed scanning the entire liver during both the arterial and portal venous phase of contrast enhancement.

METHODS

The authors analyzed data from 164 patients who underwent hepatic resection for HCC to calculate the sensitivity and specificity of these modalities. Findings of intraoperative ultrasonography followed by histologic confirmation were set as the gold standard.

RESULTS

Although sensitivity decreased with both modalities as tumors became small and well differentiated, helical CT showed a higher sensitivity than Lipiodol CT in detecting well-differentiated HCC nodules smaller than 2 cm. In contrast, Lipiodol CT was superior to helical CT for the detection of small but moderately to poorly differentiated nodules. The overall sensitivity of helical CT was higher than that of Lipiodol CT. These findings suggest that helical CT is superior in delineating early HCC, whereas Lipiodol CT is specific to the detection of intrahepatic metastases. In terms of specificity, helical CT was superior to Lipiodol CT.

CONCLUSIONS

Helical CT and Lipiodol CT are complementary modalities. At present, helical biphasic CT does not obviate the need for invasive techniques such as angiography and Lipiodol CT as preoperative examinations for HCC.

Failure of endothelin-1 to activate store-operated Ca2+ channels by lack of mobilization from intracellular Ca2+ stores in cultured bovine adrenal chromaffin cells

We have recently shown that in addition to L-type voltage-operated Ca2+ channel (VOC), endothelin-1 (ET-1) stimulation opens two types of Ca2+-permeable nonselective cation channels [designated nonselective cation channel-1 (NSCC-1) and NSCC-2]. However, in this Ca2+ entry, the involvement of store-operated Ca2+ channel (SOCC), which is suggested to exist in chromaffin cells, was unclear. Those NSCCs as well as SOCC can be pharmacologically discriminated using Ca2+ channel blockers such as SK&F 96365 and LOE 908. To clarify whether SOCC should actually exist and play a role in Ca2+ entry in chromaffin cells stimulated with ET-1, we examined the effects of removal of extracellular Ca2+, thapsigargin (TG, an inhibitor of endoplasmic reticulum Ca2+-ATPase), LOE 908 and SK&F 96365 on cytosolic free Ca2+ concentrations ([Ca2+]i) in cultured bovine adrenal chromaffin cells. After the cells were exposed to Ca2+-free medium followed by exposure to TG to deplete Ca2+ from the intracellular Ca2+ store, restoration of extracellular Ca2+ caused a gradual increase in [Ca2+]i (to about 200% of control). The increase was unaffected by LOE 908, but completely abolished by SK&F 96365. In the Ca2+-free medium, no increase in [Ca2+]i by ET-1 was observed, but the subsequent restoration of extracellular Ca2+ induced a rapid increase in [Ca2+]i (to the same level of [Ca2+]i as that evoked by ET-1 in the normal medium (1.0 mM Ca2+)). Since SK&F 96365 is also a blocker of SOCC, these results indicate that in bovine adrenal chromaffin cells, Ca2+ entry through SOCC (Ca2+ influx through the capacitative Ca2+ entry system) occurs but is comparably weak, and that it virtually does not work on the stimulation of ET-1.

Distribution of glucose-6-phosphate dehydrogenase mutations in Southeast Asia

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a heterogeneous enzyme abnormality with high frequency in tropical areas. We performed population screening and molecular studies of G6PD variants to clarify their distribution and features in Southeast Asia. A total of 4317 participants (2019 males, 2298 females) from 16 ethnic groups in Myanmar, Lao in Laos, and Amboinese in Indonesia were screened with a single-step screening method. The prevalence of G6PD-deficient males ranged from 0% (the Akha) to 10.8% (the Shan). These G6PD-deficient individuals and 12 G6PD-deficient patients who had been diagnosed at hospitals in Indonesia and Malaysia were subjected to molecular analysis by a combination of polymerase-chain-reaction-based single-strand conformation polymorphism analysis and direct sequencing. Ten different missense mutations were identified in 63 G6PD-deficient individuals (50 hemizygotes, 11 heterozygotes, and 2 homozygotes) from 14 ethnic groups. One missense mutation (1291 G-->A) found in an Indonesian Chinese, viz., G6PD Surabaya, was previously unknown. The 487 G-->A (G6PD Mahidol) mutation was widely seen in Myanmar, 383 T-->C (G6PD Vanua Lava) was specifically found among Amboinese, 871 G-->A (G6PD Viangchan) was observed mainly in Lao, and 592 C-->T (G6PD Coimbra) was found in Malaysian aborigines (Orang Asli). The other five mutations, 95 A-->G (G6PD Gaohe), 1003 G-->A (G6PD Chatham), 1360 C-->T (G6PD Union), 1376 G-->T (G6PD Canton), and 1388 G-->A (G6PD Kaiping) were identified mostly in accordance with distributions reported previously.

Identification of hepatic venous territories in liver resection by using color Doppler ultrasonography: report of two cases

OBJECTIVE

Resection of the hepatic vein because of the proximity of tumors may result in increased congestion in the noncancerous parenchyma, which in turn may lead to functional hepatic volume loss and postoperative hepatic failure, especially in a case of low hepatic reserve. However, to our knowledge, no technique for estimating the extent of dependent hepatic venous territories before hepatic resection has been established. We examined the possibility of using color Doppler ultrasonography for this purpose.

METHODS

A color Doppler system and a linear array transducer equipped with multiple Doppler frequencies ranging from 7 to 13 MHz were used intraoperatively. Two patients with hepatocellular carcinomas were examined. By tracking entire branches of the targeted vessel, from the trunk to the terminal branches extending to the liver surface, it was possible for the boundaries of the dependent areas to be projected and marked on the liver surface with either ink or electrocautery.

RESULTS

In both cases, this method was effective for either minimizing the congestive area or preserving the hepatic mass that was being drained via aberrant routes.

CONCLUSIONS

Identification of hepatic venous territories by means of color Doppler ultrasonography may provide new information about intrahepatic blood circulation and may increase the safety and curability of hepatic resection.

Two novel glucose-6-phosphate dehydrogenase variants found in newborn mass-screening for galactosaemia

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked recessive disorder in which haemolytic anaemia is the major symptom. The Beutler spot test employed in mass-screening for galactosaemia in newborns requires several intrinsic erythrocyte enzymes such as G6PD for its reaction and can theoretically detect G6PD deficiency apart from galactose-1-phosphate uridyltransferase deficiency. In this study, we detected two patients with G6PD deficiency using the quantitative Beutler test which was recently developed in our laboratory. Both patients lacked erythrocyte G6PD activity but exhibited no clinical symptoms. Molecular analysis in patients 1 and 2 revealed two novel missense mutations of C853T causing R285C and A1220C causing K407T, respectively. Molecular rather than enzymatic analysis was required in familial studies to detect and diagnose the carrier state. To date these patients have avoided oxidant stress and haemolytic diatheses have not been induced.

CONCLUSION

Our results indicate that the quantitative Beutler test can detect glucose-6-phosphate dehydrogenase deficiency of class 1 and 2 and is therefore useful for early intervention and prevention of haemolytic diathesis in patients with this disorder.

A rat model of dilated cardiomyopathy to investigate partial left ventriculectomy

BACKGROUND

This study is the first to assess a small animal model of dilated cardiomyopathy (DCM) for evaluation of partial left ventriculectomy.

METHOD

Eighteen Dahl salt-sensitive (DS) rats were divided into three groups. Six rats were fed an 8% high-salt diet from the age of 7 weeks (Group 1), and similarly six rats from 8 weeks (Group 2) and six from 9 weeks (Group 3). Blood pressure (BP) was measured by the tail-cuff method and left ventricular (LV) dimensions by echocardiography.

RESULTS

In Groups 1 and 2, systolic BP rose and reached 200 mmHg by the 10th to 11th week, when all rats died within a week without signs of heart failure. However, in Group 3, systolic BP gradually rose to 196+/-15 mmHg (mean +/- SD) at the age of 14 weeks, when LV end-diastolic diameter (EDD) was 6.2+/-0.4 mm (control 5.1+/-0.7 mm) and LV fractional shortening (FS) was 77+/-3% (control 68+/-3%). At the age of 25 to 30 weeks, all rats in Group 3 showed signs of congestive heart failure, systolic BP remained high, EDD markedly increased (8.7+/-0.6 mm), and LVFS decreased (38.9+/-8.1%). From this stage, rats survived for 13.7+/-5.9 days. We employed the Group 3 model for our pilot PLV study. Eight rats had PLV with a beating heart by plicating the LV area between the papillary muscle bases. Two rats died perioperatively but the rest survived (60% survival 3 weeks after PLV). Postoperatively, the rats' LVEDD decreased and FS improved significantly.

CONCLUSIONS

Using DS rats, we developed a DCM model for investigating PLV. The model may contribute to scientific investigation of PLV.

Pharmacological properties of calcium entry channels in A7r5 cells activated by endothelin-1

Using whole-cell recordings of patch-clamp and monitoring of the intracellular free calcium (Ca2+) concentration ([Ca2+]i), we characterized Ca2+ entry channels in A7r5 cells activated by endothelin-1 (ET-1). ET-1 activates three types of voltage-independent Ca2+ entry channels: two types of Ca2+-permeable nonselective cation channels (designated NSCC-1 and NSCC-2) and store-operated Ca2+ channel (SOCC). Furthermore, it was found that these channels can be discriminated pharmacologically using Ca2+ channel blockers such as 1-[beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl)-1-H-imidazoe l hydrochloride (SK&F 96365) and (RS)-(3,4-dihydro-6,7-dimethoxyisoquinoline-1-gamma l)-2-phenyl-N,N-di-[2-(2,3,4-trimethoxyphenyl)ethoxyl]acetamide (LOE 908). NSCC-1 is resistant to SK&F 96365 but sensitive to LOE 908, whereas NSCC-2 is sensitive to both drugs: SOCC is sensitive to SK&F 96365 but resistant to LOE 908. Using these channel blockers, we analyzed the Ca2+ entry channels involved in the ET-1-induced increase in [Ca2+]i of the cells. The increase induced by lower concentrations of ET-1 (< or = 0.1 nM) was unaffected by SK&F 96365 but it was abolished by LOE 908. In contrast, the increase caused by higher concentrations of ET-1 (> or = 1 nM) was suppressed by SK&F 96365 or LOE 908 to about 35% of controls, and abolished by combined treatment with SK&F 96365 and LOE 908. These results show that the increase in [Ca2+]i resulting from lower concentrations of ET-1 (< or = 0.1 nM) involves Ca2+ entry through only NSCC-1, whereas that resulting from higher concentrations of ET-1 involves Ca2+ entry through NSCC-1, NSCC-2 and SOCC, contributing 35%, 30% and 30%, respectively, to total Ca2+ entry.

Endothelin-1-induced contraction of rat thoracic aorta depends on calcium entry through three types of calcium channel

We have recently shown that endothelin-1 (ET-1) activates two types of Ca2+-permeable nonselective cation channels (designated NSCC-1 and NSCC-2) and store-operated Ca2+ channel (SOCC). These channels can be pharmacologically discriminated using 1-[beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl]-1-H-imidazoe l hydrochloride (SK&F 96365) (a blocker of NSCC-2 and SOCC) and (RS)-(3,4-dihydro-6,7-dimethoxyisoquinoline-1-gamma l)-2-phenyl-N,N-di-[2-(2,3,4-trimethoxyphenyl)ethyl]acetamide (LOE 908) (a blocker of NSCC-1 and NSCC-2). For our study we characterized Ca2+ channels involved in ET-1-induced contractions and increases in the intracellular free Ca2+ concentration ([Ca2+]i) using these blockers. Our results show that the response to lower concentrations of ET-1 involves only one Ca2+ channel which is sensitive to SK&F 96365 and LOE 908 (NSCC-2). In contrast, the response to higher concentrations of ET-1 involves two types of Ca2+ channel in addition to NSCC-2: one is sensitive to SK&F 96365 but resistant to LOE 908 (SOCC), and the other is resistant to SK&F 96365 but sensitive to LOE 908 (NSCC-1). Furthermore, the percentage contribution of Ca2+ entry through NSCC-1, NSCC-2 and SOCC is calculated to be 10%, 50-60% and 30-40%, respectively.

[Clinicopathological study of the testicular microlithiasis]

PURPOSE

Testicular microlithiasis (TM) is a relatively rare condition characterized by calcific concref1p4 within the seminiferous tubules. Little has been reported on the incidence or the clinical implication of TM among Japanese. To address the problem, we evaluated pathologic specimens from biopsies and orchiectomies, of testes with various conditions.

MATERIALS AND METHODS

Pathologic specimens of the testes of 200 cases, 56 from orchiectomy and 144 from testicular biopsy, were investigated.

RESULTS

The pathological diagnosis of TM was confirmed in seven (3.5%) cases, four of which were associated with germ cell tumors and the other three were obtained from testicular biopsies performed for examination of infertile men. Of the 41 patients with germ cell tumors, four (9.8%) were found to have TM, and another three (2.5%) were identified among 122 patients with infertility. The prevalence of TM is significantly higher in specimen with germ cell tumors than those without germ cell tumors (p < 0.05).

CONCLUSIONS

Although TM is rarely encountered, this condition is relatively often accompanied by testicular malignancy. Further investigation would be fundamental to ascertain the relationship between TM and testicular malignancy.