Structure and enzymatic degradation of poly(3-hydroxybutyrate) copolymer single crystals with an extracellular PHB depolymerase from Alcaligenes faecalis T1

Lamellar single crystals of four random copolymers of (R)-3-hydroxybutyrate with different hydroxyalkanoates: poly(3-hydroxybutyrate-co-8 mol%-3-hydroxyvalerate) (P(3HB-co-8%-3HV)), poly(3-hydroxybutyrate-co-10 mol%-4-hydroxybutyrate) (P(3HB-co-10%-4HB)), poly(3-hydroxybutyrate-co-8 mol%-3-hydroxyhexanoate) (P(3HB-co-8%-3HH)) and poly(3-hydroxybutyrate-co-10 mol%-6-hydroxyhexanoate) (P(3HB-co-10%-6HH)), were grown from dilute solutions of chloroform and ethanol. All single crystals have lath-shaped morphology and the second monomer units seem to be excluded from the P(3HB) crystal, on the basis of the electron diffraction diagrams. The enzymatic degradation of P(3HB-co-8%-3HH) and P(3HB-co-10%-6HH) single crystals was investigated with an extracellular PHB depolymerase from Alcaligenes faecalis T1. Adsorption of an extracellular PHB depolymerase, examined using an immuno-gold labelling technique, demonstrated a homogeneous distribution of enzyme molecules with a low concentration on the crystal surfaces. Enzymatic degradation of single crystals progressed from the edges and ends of crystals to yield narrow cracks along their long axes and the small crystal fragments. Lamellar thicknesses of single crystals and molecular weights of copolymer chains remained unchanged during the enzymatic hydrolysis. The above results support the hypothesis that the hydrophobic adsorption of the enzyme contributes to increase the mobility of molecular chains of single crystals and generate the disordered chain-packing regions. The active-site of PHB depolymerase takes place preferentially at the disordered chain-packing regions of crystal edges and ends with endo-exo enzymatic hydrolysis behaviour, termed processive degradation.

Crystallization behavior and thermal properties of melt-crystallized poly[(R)-3-hydroxybutyric acid-co-6-hydroxyhexanoic acid] films

Melt-crystallized films of poly[(R)-3-hydroxybutyric acid-co-10mol% 6-hydroxyhexanoic acid] (P[(R)-3HB-co-6HH]) were prepared by isothermal crystallization at various temperatures for 3 days, and subsequently stored at room temperature after the films formed well-developed and volume-filled spherulites. The lamellar morphologies and properties of melt-crystallized films were characterized by means of wide-angle X-ray diffraction, small-angle X-ray scattering, differential scanning calorimetry, transmission electron microscopy, and atomic force microscopy. The melting endotherm of P[(R)-3HB-co-6HH] films was composed of a broad peak starting around room temperature and of a sharper peak starting above the isothermal crystallization temperature. The stacking of flat-on lamellae with lamellar periodicity of 8-10 nm was detected on the surface of P[(R)-3HB-co6HH] films after the primary crystallization at 110 degrees C. On storage at room temperature above the Tg (-5 degrees C) of copolyester, thin crystals of 1-4 nm thickness appeared on the surface of P[(R)-3HB-co-6HH] films crystallized at 110 degrees C. These results suggest that long sequences of (R)-3HB units in a random copolyester form relatively thick P[(R)-3HB] crystalline lamellae during the primary crystallization process at a given crystallization temperature, while shorter sequences of (R)-3HB units, which are incapable of crystallizing at a given crystallization temperature, form relatively thin crystalline lamellae during the subsequent crystallization process at room temperature.

bFGF suppresses serum-deprivation-induced apoptosis in a human lens epithelial cell line

There is increasing evidence that basic fibroblast growth factor (bFGF) plays an important role in cell proliferation, differentiation, and survival in various systems. In the eye, although a truncated, dominant negative bFGF receptor in transgenic mice induced defective lens development and caused lens fiber cells to display characteristics of apoptosis, there is little direct evidence of the effect of bFGF on lens epithelial cell apoptosis. Our study examines the effects of bFGF on programmed cell death induced by serum deprivation using a human lens epithelial cell line. Cells supplemented with 20% fetal bovine serum were used as normal controls. Over a period of 7 days, the addition of 100 ng/ml bFGF effectively suppressed serum-deprived apoptosis. The expression of gamma-crystallin and major intrinsic protein, which are markers of lens cell differentiation, was not detected. Also there was no significant difference in cell proliferation between serum-deprived cells with or without bFGF. ICE (caspase-1) was expressed under both the conditions, but the level of expression between the two groups was not substantially different. bcl-2 and c-myc were upregulated only in bFGF-treated cells. Thus we speculate that the inhibitory effect of bFGF on apoptosis is through the upregulation of the inhibitor of apoptosis, instead of downregulation of the initiator. This effect appears to be independent of lens cell differentiation and proliferation.

Dorsum sellae meningioma mimicking pituitary macroadenoma: case report

BACKGROUND

A dorsum sellae meningioma is a rare occurrence. It is difficult to evaluate dorsum sellae meningiomas preoperatively from the viewpoint of neuroimaging. We report a rare case of dorsum sellae meningioma mimicking pituitary macroadenoma in a 73-year-old woman.

CASE PRESENTATION

The patient presented with bitemporal hemianopsia and panhypopituitarism. Magnetic resonance imaging demonstrated a bright, homogeneously enhancing intra- and suprasellar mass and a hypointense region in this mass, which was interpreted as a dorsum sellae. Transsphenoidal extirpation was used because of a suspicion of nonsecreting pituitary macroadenoma. Histopathologically, the tumor was diagnosed as a meningioma. Superselective external carotid angiography before the second surgery revealed that the mass was supplied by the left accessory middle meningeal artery and appeared to originate from dorsum sellae. After preoperative embolization, the patient developed hyponatremia. The tumor was subtotally removed via a transcranial route, and the attachment to the dorsum sellae was coagulated extensively. She did well after a second surgical procedure.

CONCLUSION

These radiologic findings may be useful in differentiating dorsum sellae meningioma from pituitary macroadenoma.

Generation of free radicals and the damage done to the sarcoplasmic reticulum during reperfusion injury following brief ischemia in the canine heart

Free radical generation was studied by the electron spin resonance (ESR) technique using alpha-phenyl N tert butyl nitrone (PBN) in a brief ischemia-reperfusion model of the canine heart, and correlated with biochemical changes of the sarcoplasmic reticulum (SR). ESR spectra (aH=0.3-0.4mT, aN=1.43-1.58mT) were observed as PBN spin adducts, which peaked at levels 5-fold above the control levels at 5 min after reperfusion. The simulated coupling constants of PBN spin adducts suggested that the sample should contain at least 2 carbon-centered radicals at 5 min after reperfusion (radical A: aH=0.350mT, aN=1.485mT; radical B: aH=0.370mT, aN=1.615 mT). At this time point, a significant reduction in Ca-ATPase activity of the SR was found without degradation of the major ATPase protein. Superoxide dismutase (SOD) significantly reduced the intensity of the PBN spin adduct signals and preserved the Ca-ATPase activity of the SR to 80% of the control level. Reperfusion injury after brief ischemia may be the result of inactivation of intracellular Ca-ATPase by free radicals generated during reperfusion, and SOD contributes to the protective effect by scavenging the radicals.

[Resected case of synchronous double cancer of lung and ovarium]

A 45-year-old woman was admitted to our department for a tumor shadow in the right lung on chest rentogenogram and chest CT. Detailed examination led to the diagnosis of simultaneous lung cancer and ovarian cancer. No abnormality was found in the liver. Serum AFP level was 113.8 ng/ml preoperatively, but deceased upper lobectomy of the right lung to 11.4 ng/ml on the 15th day postoperatively. Immunohistochemical study revealed positive staining of carcinoma cells with anti AFP serum.

Osmotic response element is required for the induction of aldose reductase by tumor necrosis factor-alpha

Induction of aldose reductase (AR) was observed in human cells treated with tumor necrosis factor-alpha (TNF-alpha). AR protein expression increased severalfold in human liver cells after 1 day of exposure to 100 units/ml TNF-alpha. An increase in AR transcripts was also observed in human liver cells after 3 h of TNF-alpha treatment, reaching a maximum level of 11-fold at 48 h. Among the three inflammatory cytokines: TNF-alpha, interleukin-1, and interferon-gamma, TNF-alpha (100 units/ml) gave the most induction of AR. Differences in the pattern of AR induction were observed in human liver, lens, and retinal pigment epithelial cells with increasing concentrations of TNF-alpha. A similar pattern of AR promoter response was observed between TNF-alpha and osmotically stressed human liver cells. The deletion of the osmotic response element (ORE) abolished the induction by TNF-alpha and osmotic stress. A point mutation that converts ORE to a nuclear factor-kappaB (NF-kappaB) sequence abolished the osmotic response but maintained the TNF-alpha response. Electrophoretic gel mobility shift assays showed two NF-kappaB proteins, p50 and p52, capable of binding ORE sequence, and gel shift Western assay detected NF-kappaB proteins p50 and p65 in the ORE complex. Inhibitors of NF-kappaB signaling, lactacystin, and MG132 abolished the AR promoter response to TNF-alpha.

Etoposide enhances the lethal effect of radiation on breast cancer cells with less damage to mammary gland cells

PURPOSE

In the present study, the cytotoxic effects of anticancer drug treatment plus radiation on breast cancer and normal mammary gland cells were investigated in vitro.

METHODS

Breast cancer and adjacent mammary gland tissue was obtained from surgically resected specimens from 13 premenopausal female patients, and was cultured. Cultured cells were treated with radiation and etoposide, and sensitivities were evaluated using an MTT assay.

RESULTS

In breast cancer cells, radiation alone had a cytotoxic effect. When etoposide was added, synergistic effects were achieved which were independent of the radiation dose. The cytotoxicity of etoposide against normal gland cells, however, was much the same as that against cancer cells, and no synergistic effects were observed in normal cells even when radiation was added.

CONCLUSIONS

Radiation combined with etoposide showed lethal effects against breast cancer cells with less damage to normal mammary gland cells.

Simulation of a zero-dispersion filter monochromator for image-spectroscopic measurements

I propose a novel filter monochromator for image spectroscopic measurements. An aberration-corrected double monochromator that I reported on previously [Appl. Opt. 36, 7114-7118 (1997)] is modified for use in a zero-dispersion mode. An incident image on the entrance aperture is focused onto an imaging detector attached on the exit focal plane with a spectral bandwidth determined by the width of the intermediate slit. Unlike a conventional interference filter, the spectral bandwidth and its center wavelength are determined arbitrarily while both a low stray-light level and the sharp cutoff characteristics of the wavelength are maintained. To demonstrate the real capabilities, ray-tracing simulations are carried out. I also discuss the problem of wavelength purity in the spectroscopic image.

Oxidative stress induces differential gene expression in a human lens epithelial cell line

PURPOSE

To identify differentially expressed genes in a human lens epithelial cell line exposed to oxidative stress.

METHODS

Reverse transcriptase-polymerase chain reaction (RT-PCR) differential display was used to evaluate differential gene expression in a human lens epithelial cell line (SRA 01-04) when cells were exposed for 3 hours to a single bolus of 200 microM hydrogen peroxide. Differentially expressed genes were identified through DNA sequencing and a nucleotide database search. Differential expression was confirmed by northern blot and RT-PCR analyses.

RESULTS

Using 18 primer sets, 28 RT-PCR products were differentially expressed between control and hydrogen peroxide-treated cells. In stressed cells, mitochondrial transcripts nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 4 and cytochrome b were downregulated 4-fold. Of the cytoplasmic mRNAs, glutamine cyclotransferase decreased 10-fold, whereas cytokine-inducible nuclear protein, alternative splicing factor 2, and beta-hydroxyisobutyryl-coenzyme A hydrolase increased 2-, 4-, and 10-fold, respectively. Analysis of mitochondrial transcripts in a 24-hour time course showed that NADH dehydrogenase subunit 4 mRNA decreased by 2-fold as early as 1 hour after oxidative stress, whereas the rate of decrease was slower for cytochrome b, cytochrome oxidase III, and 16S rRNA.

CONCLUSIONS

Oxidative stress induced specific expressed gene changes in hydrogen peroxide-treated lens cells, including genes involved in cellular respiration and mRNA and peptide processing. These early changes may reflect pathways involved in the defense, pathology, or both of the lens epithelium, which is exposed to oxidative stress throughout life.

Development and clinical application of high performance liquid chromatography for the simultaneous determination of plasma levels of theophylline and its metabolites without interference from caffeine

A high performance liquid chromatography (HPLC) method has been developed for the simultaneous determination of plasma levels of theophylline and its metabolites without interference from caffeine or caffeine metabolites. The method is simple and of practical use because it is applicable even to plasma samples from patients who take caffeine-containing beverages. The method was also reproducible with a coefficient of variation of less than 5% for each analyte. The levels of theophylline, determined by HPLC, were validated by their high correlation to the levels obtained by fluorescence polarization immunoassay. HPLC was used to determine theophylline levels in patients with bronchial asthma. The data revealed that the ratio of 1,3-dimethyluric acid, the major metabolite of theophylline, to theophylline concentration in the plasma was within a narrow range in most patients (0.055 +/- 0.01, n = 66), regardless of the method of theophylline administration or the time of blood sampling. Conversely, this ratio was as low as 0.027 +/- 0.005 in the patient with a long plasma half-life of theophylline. These results suggest that it may be possible to predict the plasma half-life of theophylline for each patient from a single blood sample. This may be useful when planning theophylline administration, especially in patients with abnormal theophylline metabolism.

[Effectiveness of hypoallergenic rice-by cast analysis]

Rice is the main food taken every day in Japan. We introduced hypoallergenic rice (95% of albumin and globulin were taken off by hyperpressure method) for 4 weeks to 7 atopic dermatitis patients (m 3, f 4), 11 mo-4 y 8 m (mean 3 y 2 m) who showed the RAST score of rice 1 or more. Stimulation Index by CAST (cellular antigen stimulation test) were compared before and after taking the rice (50-100 g). By albumin (0.1-100 micrograms/ml), maximum decreases of S.I. were 22.4-96.5% (mean 70.9) and by globulin maximum decreases of S.I. were (0.1-100 micrograms/ml) 33.3-97.0% (mean 72.9). In all the patients the skin conditions were improved.

A Lys644Glu substitution in fibroblast growth factor receptor 3 (FGFR3) causes dwarfism in mice by activation of STATs and ink4 cell cycle inhibitors

Missense mutations of human fibroblast growth factor receptor 3 (FGFR3) result in several skeletal dysplasias, including hypochondroplasia, achondroplasia and thanatophoric dysplasia. To study the function of FGFR3 in bone growth and to create animal models for the FGFR3-related inherited skeletal disorders, we introduced a point mutation (Lys644Glu) into the murine FGFR3 genome using a knock-in approach. We found that the Lys644Glu mutation resulted in retarded endochondral bone growth with severity directly linked to the expression level of the mutated Fgfr3. Mice heterozygous for the mutation ( Fgfr3(TD/+) ) expressed the mutant allele at approximately 20% of the wild-type level and exhibited a mild bone dysplasia. However, when the copy number of the mutant allele increased from one (Fgfr3(TD/+) to two (Fgfr3(TD/TD), the retardation of bone growth became more severe and showed phenotypes resembling those of achondroplasia patients, characterized by a dramatically reduced proliferation of growth plate cartilage, macrocephaly and shortening of the long bones, which was most pronounced in the femur. Molecular analysis revealed that expression of the mutant receptor caused the activation of Stat1, Stat5a and Stat5b, and the up-regulation of p16, p18 and p19 cell cycle inhibitors, leading to dramatic expansion of the resting zone of chondrocytes at the expense of the proliferating chondrocytes. The mutant growth plates consequently were in a less active state and generated fewer maturing and hypertrophic chondrocytes. These data provide direct genetic evidence that the point mutations in FGFR3 cause human skeletal dysplasias and uncover a mechanism through which the FGFR3 signals regulate bone growth by modulating expression of Stats and ink4 cell cycle inhibitors.

Langerhans cell histiocytosis localized to the eyelid

We treated a 46-year-old Japanese man with Langerhans cell histiocytosis (LCH) localized to the eyelid alone. He was cured successfully by local and complete resection. Results of pathological examinations of the excised tumor demonstrated diffuse infiltration by atypical histiocytic cells with eosinophilic cytoplasm and convoluted nuclei, S100 immunoreactivity, and tennis-racket-shaped Birbeck granules. Based on these pathological findings, we diagnosed LCH. Clinical examination revealed no LCH involvement in other parts of the body. To our knowledge, there has been only one report of LCH occurring as an isolated tumor in the eyelid. Generally LCH has been reported in children or young people. This is an unusual case of LCH isolated to the eyelid of an older patient.

Paroxysmal atrial fibrillation as a cause of potentially lethal ventricular arrhythmia with myocardial ischemia in hypertrophic cardiomyopathy--a case report

The mechanism(s) of myocardial ischemia in hypertrophic cardiomyopathy remain unclear. In this report, the authors present a 75-year-old Japanese woman with nonobstructive hypertrophic cardiomyopathy in whom paroxysmal atrial fibrillation caused severe myocardial ischemia and induced sustained ventricular tachycardia. Her coronary angiogram showed normal findings, and no ischemic changes were provoked by either physical exercise testing or dobutamine stress echocardiography under sinus rhythm. In view of these findings, the rapid ventricular response in the absence of atrial contraction may aggravate or induce myocardial ischemia and predispose patients with hypertrophic cardiomyopathy to develop lethal ventricular arrhythmia.

A novel molecular determinant for cAMP-dependent regulation of the frog heart Na+-Ca2+ exchanger

Na+-Ca2+ exchanger is one of the major sarcolemmal Ca2+ transporters of cardiac myocytes. In frog ventricular myocytes the exchanger is regulated by isoproterenol via a beta-adrenoreceptor/adenylate-cyclase/cAMPdependent signaling pathway providing a molecular mechanism for the relaxant effect of the hormone. Here, we report on the presence of a novel exon of 27-base pair insertion, which generates a nucleotide binding motif (P-loop) in the frog cardiac Na+-Ca2+ exchanger. To examine the functional role of this motif, we constructed a full-length frog heart Na+-Ca2+ exchanger cDNA (fNCX1a) containing this exon. The functional expression of fNCX1a in oocytes showed characteristic voltage dependence, divalent (Ni2+, Cd2+) inhibition, and sensitivity to cAMP in a manner similar to that of native exchanger in frog myocytes. In oocytes expressing the dog heart NCX1 or the frog mutant (DeltafNCX1a) lacking the 9-amino acid exon, cAMP failed to regulate Na+-dependent Ca2+ uptake. We suggest that this motif is responsible for the observed cAMP-dependent functional differences between the frog and the mammalian hearts.

Effect of omental lipid fraction on enhancement of skin flap survival

The effect of an omental lipid fraction on the rate of skin flap survival in the back of the rat was assessed by planimetric and histological examination. Compared with the control group, those rats treated with the omental lipid fraction showed significant improvement of the flap survival area. On histological examination, the flap instilled with the omental lipid fraction showed vasodilatation and neovascularization between the flap and the bed. A topical application of the omental lipid fraction enhanced the skin flap survival area, and showed vasodilatation in the flap and neovascularization between the skin flap and the recipient bed.

Examination of prognostic factors after resection of pulmonary metastasis of osteosarcoma by multivariate analysis

Prognostic factors for the case of pulmonary metastasis of osteosarcoma was examined using the multivariate analysis. 1) The 3-year survival rate after operation of primary focus in 23 cases was 34.8% and the 5-year survival rate was 30.4%. The 3-year survival rate after the first operation of pulmonary metastasis was 30.4% and the 5-year survival rate was 12.2%. No deaths attributed to operation were found. 2) Gender, age, histological type, solitary or multiple pulmonary metastasis, laterality, number of pulmonary metastatic tumors, TDT and DFI were examined, and the laterality, number of pulmonary metastatic tumors and DFI were considered to be useful prognostic factors. DFI among them was most closely associated with postoperative survival days. 3) A significant difference in the number of excised nodules was found between the DFI less than 90 days group and the DFI not less than 90 days group, and the number in the former group was significantly larger. 4) It was suggested that postoperative observation and close examination for pulmonary metastasis at about 3 months intervals after of primary focus are important, and also, positive or negative pulmonary metastasis as the time of examination, particularly, the number metastatic nodules of less than 5 or not less than 5, are reflected in the prognosis. 5) Expected survival time after the first operation pulmonary metastasis appeared possible to estimate as 3.0 x DFI days.

[High uptake on 11C methionine PET scan in the pituitary gland of a patient with cerebral glioma after surgical abortion]

Positron emission tomography (PET) with various tracers provides physiologic and biochemical information of living organs. Since radiologic examinations are usually avoided in pregnant women, mainly because of the radiation risk to the fetus, little is known about the effect of pregnancy on cerebral blood flow and metabolism. This paper reports findings of a 11C methionine PET scan of the pituitary gland in a woman after an abortion. The patient was a 31-year-old woman who suffered a seizure in the 9th week of her second pregnancy. On admission, computed tomography showed an abnormal mass lesion in the right frontal lobe, and a brain tumor was suspected. The patient and her family asked that that pregnancy be terminated. Seven days after a surgical abortion, methionine PET was performed. The scan showed high methionine uptake in the pituitary gland as well as in the right frontal lobe tumor. We suspected that another tumor was present in the pituitary gland. The right frontal tumor was partially resected, and pathologic examination of the resected specimen showed an astrocytoma (grade 2). After the operation, the patient received 50 Gy irradiation and chemotherapy. Two months after the operation, we performed a second methionine PET scan, which showed high uptake in the residual right frontal tumor but not in the pituitary gland. Results of other radiologic studies of the pituitary gland were normal. These findings suggest that the transport of 11C methionine into the pituitary gland may increase during pregnancy. Moreover, the pituitary gland of pregnancy should be a part of the differential diagnosis of pituitary adenomas in PET scanning. The change in physiologic uptake by the female pituitary gland should be taken into account in the diagnosis of pituitary adenoma with methionine PET.

A case of pulmonary metastases of synovial sarcoma surviving for a long period after active surgery

The patient was a 24-year-old woman. She underwent marginal excision of synovial sarcoma originating in the right femoral soft tissue at the age of 18, followed by local radiation therapy and chemotherapy. At the age of 20, abnormal shadow was indicated in bilateral lungs on plain roentgenography of the chest, and she underwent open-chest surgery for excision of bilateral pulmonary metastatic tumors. She was subjected to bilateral thoracotony repeatedly thereafter for a total of 5 times, and all of the metastatic foci detected in each operation were resected. Consequently, she has been surviving for a long period of about 7 years. The therapeutic outcome of tumor of bone soft tissue is greatly affected by its pulmonary metastasis. Although the therapeutic outcome has recently been improved by large dose chemotherapy and active excision of metastatic foci in the lung, survival time in the case of synovial sarcoma, giant cell sarcoma and Ewing's sarcoma is not very long yet. In the present study, we observed a patient who had lung metastasis of synovial sarcoma of which prognosis is generally considered poor has been surviving for a long time of 7 years owing to active excision of pulmonary metastatic foci. The relation of the present prognostic factors to those in the past were compared.

An immunohistochemical study of amyloid P component, apolipoprotein E and ubiquitin in human and murine amyloidoses

Amyloid P component (AP) and apolipoprotein E (Apo E), which are known to be minor constituents of amyloid deposits, commonly are associated with almost all types of amyloid deposits. In this study, the distribution of AP-, Apo E- and ubiquitin (Ub)-immunoreactivity (IR) in amyloid deposits in the liver and spleen of human systemic amyloidosis (34 autopsy cases: 17 immunoglobulin light chain derived, 17 amyloid A protein derived) and experimental murine amyloidosis is examined using an immuno-histochemical technique. In human cases, all of the amyloid deposits examined showed colocalization of AP- and Apo E-IR with individual amyloid proteins. In experimental amyloidosis, AP-IR of amyloid deposits in the liver and spleen and Apo E-IR in the liver were seen uniformly throughout this experiment. In contrast, Apo E-IR in the spleen was not uniform at the phase of amyloid deposition. At 4 weeks and at 16 weeks after casein injection, Apo E-IR was unevenly distributed in amyloid deposits in the perifollicular area; however, from 6 to 12 weeks it was seen to be uniform. Ubiquitin-IR of amyloid deposits in human cases was seen in 22 of 34 livers and in 22 of 33 spleens. In experimental amyloidosis, Ub-IR of amyloid deposits was demonstrated in the space of Disse in all mice examined, and there appeared to be a gradual increase in intensity with the amount of amyloid deposition. However, in the spleen, amyloid deposits did not react with anti-Ub antibody in any phase of amyloid induction. These results suggest that Apo E and Ub are not always associated with the process of amyloid deposition and may appear in a deposit after the deposition.

An early systolic sound associated with midventricular obstruction in a patient with hypertrophic cardiomyopathy

A 57-year-old woman was admitted for examination because of chest discomfort. Transthoracic echocardiography was performed and she was diagnosed as having hypertrophic cardiomyopathy. An echocardiogram also revealed that she had midventricular obstruction with a pressure gradient of 125 mmHg determined by Doppler echocardiography. A phonocardiogram showed an early systolic sound and the beginning of the sound coincided with the time of septal-posterior wall contact. In addition, the timing also corresponded to the sudden obstruction of blood flow in the region of the midventricular narrowing. Furthermore, this sound markedly decreased with the reduction in pressure gradient caused by cibenzoline treatment. Thus, it was concluded that the early systolic sound was associated with midventricular obstruction and produced by a rapid deceleration of the interventricular flow caused by midventricular obstruction.

The adsorption of substrate-binding domain of PHB depolymerases to the surface of poly(3-hydroxybutyric acid)

The binding characteristic of PHB depolymerase has been studied by using glutathione S-transferase (GST) fusion proteins with substrate-binding domain of three bacterial PHB depolymerases, Alcaligenes faecalis, Comamonas acidovorans and Comamonas testosteroni. Analysis using immuno-gold labeling technique and transmission electron microscopy indicated that a novel GST fusion protein derived from A. Faecalis enzyme adsorbed to the surface of poly(3-hydroxybutyric acid) (P(3HB)) single crystals like other fusion proteins. Comparison of inhibiting degree of P(3HB) powder hydrolysis activity of PHB depolymerase by fusion proteins indicated that three fusion proteins bind to P(3HB) powder in the same degree. The measurement of the surface hydrophobicity of proteins suggests that the interaction of the substrate-binding domain with insoluble P(3HB) may include not only a hydrophobic effect but also molecule-specific contacts.

Epidural hematoma of the clivus. Case report

This 8-year-old boy presented with a rare case of epidural hematoma of the clivus and atlantoaxial dislocation caused by a hyperflexion injury sustained in a traffic accident. Magnetic resonance (MR) imaging demonstrated an epidural hematoma in the posterior fossa that compressed the pons and medulla. On admission, the patient was confused and had bilateral abducens palsy. He was treated conservatively, and 6 months after admission, the epidural hematoma on the clivus had disappeared on MR imaging and the bilateral abducens palsy was cured. Only two such cases have been reported in the literature. In this report, the authors discuss the mechanism of hematoma formation in this region of the brain.