The impact of intraoperative pericardial three-dimensional echocardiography for the atrioventricular valve repair in the patient with congenital heart disease

Background

Atrioventricular valve (AVV) regurgitation enormously affected the survival outcome of the patients with congenital heart disease (CHD). However, the image quality by use of transthoracic echocardiography has not reached a level that is sufficient, and also, three-dimensional echocardiography, which is useful to clarify complex AVV anatomy, cannot be applied for the patients less than 15kg, to guide for the AVV repair in pediatric patients. We try to show surgeons more precise three-dimensional images about an AVV by using intraoperative pericardial three-dimensional echocardiography (IP3DE) and improve the surgical outcome.

Purpose

To determine the efficacy of IP3DE by assessing the surgical outcome of an AVV repair and re-intervention rate.

Method

Eighty-five patient with CHD who underwent atrioventricular repair with significant regurgitation (Grade 2–4+) before operation were divided into two groups imaged IP3DE or not, in our hospital from 1993 to 2020. We assessed the surgical outcome and re-intervention rate between two arms and re-evaluate AVV images before surgery compared to the IP3DE.

Result

IP3DE was performed in forty-six patients (IP3DE group) and thirty-nine patients were not (control group). Median age at AVV repair was 3.0/2.8 years, respectively. The AVV was tricuspid (n=25), mitral (n=41), or common (n=19). The IP3DE group had a significantly higher improvement in regurgitation of AVV (IP3DE: Grade 3.2±0.3 → 1.7±0.3 vs Control: Grade 2.8±0.3 → 1.8±0.3, p<0.05). Fifty-nine percent of the IP3DE group was successful outcome (Grade<1+ after repair). There was no significant difference in the rate of re-intervention after surgery between two groups. In multivariate analysis, using IP3DE contributed to successful outcome for AVV repair (OR: 4.66, 95% CI: 1.46–14.8, p<0.01). The different and/or additional anatomical AVV findings were obtained in sixty-one percent of patients by the IP3DE.

Conclusion

IP3DE contributes to successful outcome for AVV repair by obtaining further information on complicated AVV anatomy in congenital heart disease. IP3DE also enables both cardiovascular surgeons and cardiologists to share the accurate and detail “surgeon's view” in the operating room for planning of AVV repair.

Funding Acknowledgement

Type of funding sources: None.

A Neural Mechanism of Cue-Outcome Expectancy Generated by the Interaction Between Orbitofrontal Cortex and Amygdala

Taste perception is important for animals to take adequate nutrients and avoid toxins for their survival. Appetitive and aversive behaviors are produced by value evaluation of taste and taste expectation caused by other sensations. The value evaluation, coupled with a cue presentation, produces outcome expectation and guides flexible behaviors when the environment is changed. Experimental studies demonstrated distinct functional roles of basolateral amygdala (ABL) and orbitofrontal cortex (OFC) in value evaluation and adaptive behavior. ABL is involved in generating a cue-outcome association, whereas OFC makes a contribution of generating a cue-triggered expectation to guide adaptive behavior. However, it remains unclear how ABL and OFC form their functional roles, with the learning of adaptive behavior. To address this issue, we focus on an odor discrimination task of rats and develop a computational model that consists of OFC and ABL, interacting with reward and decision systems. We present the neural mechanisms underlying the rapid formation of cue-outcome association in ABL and late behavioral adaptation mediated by OFC. Moreover, we offer 2 functions of cue-selective neurons in OFC: one is that the activation of cue-selective neurons transmits value information to decision area to guide behavior and another is that persistent activity of cue-selective neurons evokes a weak activity of taste-sensitive OFC neurons, leading to cue-outcome expectation. Our model further accounts for ABL and OFC responses caused by lesions of these areas. The results provide a computational framework of how ABL and OFC are functionally linked through their interactions with the reward and decision systems.

Evolving affinity between Coulombic reversibility and hysteretic phase transformations in nano-structured silicon-based lithium-ion batteries

Nano-structured silicon is an attractive alternative anode material to conventional graphite in lithium-ion batteries. However, the anode designs with higher silicon concentrations remain to be commercialized despite recent remarkable progress. One of the most critical issues is the fundamental understanding of the lithium-silicon Coulombic efficiency. Particularly, this is the key to resolve subtle yet accumulatively significant alterations of Coulombic efficiency by various paths of lithium-silicon processes over cycles. Here, we provide quantitative and qualitative insight into how the irreversible behaviors are altered by the processes under amorphous volume changes and hysteretic amorphous-crystalline phase transformations. Repeated latter transformations over cycles, typically featured as a degradation factor, can govern the reversibility behaviors, improving the irreversibility and eventually minimizing cumulative irreversible lithium consumption. This is clearly different from repeated amorphous volume changes with different lithiation depths. The mechanism behind the correlations is elucidated by electrochemical and structural probing.

[Senning operation for transposition of great arteries in a premature baby]

A male baby was delivered by emergency cesarean section due to fetal distress at 30 weeks of gestational age with a birth weight of 813 g. By fetal echocardiography, the patient had been diagnosed with transposition of great arteries (type 1). Early two-staged arterial switch operation was planned after 34 gestational age avoiding intracranial hemorrhage under cardiopulmonary bypass. At 19 days of life, vegetation was revealed on the pulmonary valve by echocardiography, so he was diagnosed as infectious endocarditis. Cefotaxime and gamma-globulin were given intravenously for 4 weeks. While waiting for the increase in the body weight, desaturation from chronic respiratory distress syndrome was exacerbated. At 8 months old, urgent Senning operation was performed to improve desaturation. The patient was discharged at 20 post operative day. We conclude that Senning operation can be feasible operation in such a complicated case.

Regulation of neurite outgrowth mediated by neuronal calcium sensor-1 and inositol 1,4,5-trisphosphate receptor in nerve growth cones

Calcium acts as an important second messenger in the intracellular signal pathways in a variety of cell functions. Strictly controlled intracellular calcium is required for proper neurite outgrowth of developing neurons. However, the molecular mechanisms of this process are still largely unknown. Neuronal calcium sensor-1 (NCS-1) is a high-affinity and low-capacity calcium binding protein, which is specifically expressed in the nervous system. NCS-1 was distributed throughout the entire region of growth cones located at a distal tip of neurite in cultured chick dorsal root ganglion neurons. In the central domain of the growth cone, however, NCS-1 was distributed in a clustered specific pattern and co-localized with the type 1 inositol 1,4,5-trisphosphate receptor (InsP(3)R1). The pharmacological inhibition of InsP(3) receptors decreased the clustered specific distribution of NCS-1 in the growth cones and inhibited neurite outgrowth but did not change the growth cone morphology. The acute and localized loss of NCS-1 function in the growth cone induced by chromophore-assisted laser inactivation (CALI) resulted in the growth arrest of neurites and lamellipodial and filopodial retractions. These findings suggest that NCS-1 is involved in the regulation of both neurite outgrowth and growth cone morphology. In addition, NCS-1 is functionally linked to InsP(3)R1, which may play an important role in the regulation of neurite outgrowth.

Secondary osteoporosis in long-term bedridden patients with cerebral palsy

BACKGROUND

The aim of the present paper was to investigate 20 pediatric patients with cerebral palsy and secondary osteoporosis and consider the efficacy, influence and index of treatment.

METHODS

A total of 10 boys and 10 girls, age 1-16 years (mean 7.6 years) with secondary osteoporosis and cerebral palsy treated for 6 months, were studied. Bone mineral density (BMD) was measured. The bone turnover markers were measured just before and 4 months after treatment or at the time of early discontinuation of treatment. The treatment was classified into two groups: vitamin D (alfacarcidol) only; and with bisphosphonate (risedronate).

RESULTS

Monotherapy with alfacarcidol was effective for secondary osteoporosis in children, but when used in combination with risedronate it was even more effective in improving BMD. In the two groups, bone-specific alkaline phosphate (BAP) decreased from pretreatment to post-treatment assessment in all but one case, but there was no significant correlation in the difference in DeltaBAP with DeltaBMD. DeltaBAP assumed changes in BAP in treatment either before or after, and DeltaBMD also assumed changes in BMD. N-telopeptides of type I collagen (NTX)/Cr decreased in all cases. The correlation of DeltaNTX/Cr with DeltaBMD was not significant. The therapy and its efficacy did not correlate to the patients' age, sex, medicine regimen or enteral nutrition.

CONCLUSIONS

Risedronate therapy is effective for patients presenting with secondary osteoporosis with cerebral palsy. Moreover, it is desirable to treat patients more aggressively from the early stage because risedronate is not affected by the patients' other factors.

Cost-effective analysis of different algorithms for the diagnosis of hepatitis C virus infection

We compared the cost-benefit of two algorithms, recently proposed by the Centers for Disease Control and Prevention, USA, with the conventional one, the most appropriate for the diagnosis of hepatitis C virus (HCV) infection in the Brazilian population. Serum samples were obtained from 517 ELISA-positive or -inconclusive blood donors who had returned to Fundação Pró-Sangue/Hemocentro de São Paulo to confirm previous results. Algorithm A was based on signal-to-cut-off (s/co) ratio of ELISA anti-HCV samples that show s/co ratio > or =95% concordance with immunoblot (IB) positivity. For algorithm B, reflex nucleic acid amplification testing by PCR was required for ELISA-positive or -inconclusive samples and IB for PCR-negative samples. For algorithm C, all positive or inconclusive ELISA samples were submitted to IB. We observed a similar rate of positive results with the three algorithms: 287, 287, and 285 for A, B, and C, respectively, and 283 were concordant with one another. Indeterminate results from algorithms A and C were elucidated by PCR (expanded algorithm) which detected two more positive samples. The estimated cost of algorithms A and B was US$21,299.39 and US$32,397.40, respectively, which were 43.5 and 14.0% more economic than C (US$37,673.79). The cost can vary according to the technique used. We conclude that both algorithms A and B are suitable for diagnosing HCV infection in the Brazilian population. Furthermore, algorithm A is the more practical and economical one since it requires supplemental tests for only 54% of the samples. Algorithm B provides early information about the presence of viremia.

Association of circulating antibodies against double-stranded and single-stranded DNA with thyroid autoantibodies in Graves' disease and Hashimoto's thyroiditis patients

The occurrence of antinuclear antibody (ANA), rheumatoid factor (RF), antibodies to double-stranded DNA (anti-dsDNA) and to single-stranded DNA (anti-ssDNA) was investigated in 51 patients with autoimmune thyroid diseases (AITD), and in 25 matched control subjects. In comparison with controls, the prevalence of anti-dsDNA was 74.5% in AITD patients (p=0.0001), 82.0% in 39 hyperthyroid Graves' disease (GD) (p=0.0001), and 50.0% in 12 euthyroid Hashimoto's thyroiditis (HT) patients (p=0.0001). The prevalence of anti-ssDNA was 90.1% in AITD (94.8% in GD and 75% in HT; p=0.001). The concentration of both anti-dsDNA and anti-ssDNA were higher (p=0.002) in AITD, in GD (p=0.001), and in HT (p=0.01) patients than in controls. Two patients with AITD were identified as positive for ANA. RF was detected in 4 AITD patients. Positive correlation was noted between anti-dsDNA with T4 (p=0.001), T3 (p=0.002), thyroid peroxidase antibody (anti-TPO) (p=0.0001), and TSH (p=0.001) values but not with thyroglobulin antibody (anti-Tg). Serum anti-ssDNA values were also correlated with T3 (p=0.0001), TSH (p=0.003), and anti-TPO (p=0.0001). However, by using a multiple regression analysis only anti-TPO remained associated with anti-dsDNA and both anti-Tg and anti-TPO with anti-ssDNA values. The predisposition to develop systemic autoimmune disorders is not influenced by thyroid hormones. The elevated prevalence of serum anti-dsDNA and anti-ssDNA in AITD patients points out that we must be aware of the risk for predisposition for the development of other systemic autoimmune diseases.

Sequence variation of the cytochrome b gene of various human infecting members of the genus Leishmania and their phylogeny

The Cytochrome b (Cyt b) gene has proved to be useful for identification and classification of many mammals and plants. In order to evaluate the utility of this gene for discrimination of Leishmania parasites as well as for exploring their phylogenetic relationships, we determined the nucleotide sequences of the Cyt b gene from 13 human-infecting Leishmania species (14 strains) from the New and Old Worlds. The Cyt b genes, approximately 1080 base pairs, were found to be A/T rich, and their 5' terminal-editing regions were highly conserved. The nucleotide sequence variation among them was enough to discriminate parasite species; 245 nucleotide positions were polymorphic and 190 positions were parsimony informative. The phylogenetic relationships based on this gene, showed good agreement with the classification of Lainson & Shaw (1987) except for the inclusion of L. (L.) major in the L. (L.) tropica complex and the placement of L. tarentolae in another genus. These data show that the Cyt b gene is useful for phylogenetic study of Leishmania parasites.

[A case of intractable epilepsy showing frequent gelastic seizures by administration of clobazam]

A 13-year-old boy patient had severe mental retardation and spastic quadriplegia due to fetal distress and hypoxic-ischemic brain damage in the perinatal period. He suffered from West syndrome at the age of 7 months, and subsequently was diagnosed as having symptomatic localization-related epilepsy. His intractable epileptic seizures were not controlled by combination of various antiepileptic drugs. After prescribing nitrazepam and zonisamide for more than 1 year, we added clobazam (CLB), which has been marketed in Japan since 2000, to this combination therapy. After the introduction of CLB, tonic seizures disappeared. However, gelastic seizures laughing with a stiff face and a wry mouth appeared frequently before falling asleep, and sleep disturbance worsened subsequently. It has not been reported previously that gelastic seizures are a side effect of CLB, although irritability and sleep disturbance have been described.

Identification and characterization of a synaptojanin 2 splice isoform predominantly expressed in nerve terminals

We have previously identified synaptojanin 1, a phosphoinositide phosphatase predominantly expressed in the nervous system, and synaptojanin 2, a broadly expressed isoform. Synaptojanin 1 is concentrated in nerve terminals, where it has been implicated in synaptic vesicle recycling and actin function. Synaptojanin 2A is targeted to mitochondria via a PDZ domain-mediated interaction. We have now characterized an alternatively spliced form of synaptojanin 2 that shares several properties with synaptojanin 1. This isoform, synaptojanin 2B, undergoes further alternative splicing to generate synaptojanin 2B1 and 2B2. Both amphiphysin and endophilin, two partners synaptojanin 1, bind synaptojanin 2B2, whereas only amphiphysin binds synaptojanin 2B1. Sequence similar to the endophilin-binding site in synaptojanin 1 is present only in synaptojanin 2B2, and this sequence was capable of affinity purifying endophilin from rat brain. The Sac1 domain of synaptojanin 2 exhibited phosphoinositide phosphatase activity very similar to that of the Sac1 domain of synaptojanin 1. Site-directed mutagenesis further illustrated its functional similarity to the catalytic domain of Sac1 proteins. Antibodies raised against the synaptojanin 2B-specific carboxyl-terminal region identified a 160-kDa protein in brain and testis. Immunofluorescence showed that synaptojanin 2B is localized at nerve terminals in brain and at the spermatid manchette in testis. Active Rac1 GTPase affects the intracellular localization of synaptojanin 2, but not of synaptojanin 1. These results suggest that synaptojanin 2B has a partially overlapping function with synaptojanin 1 in nerve terminals, with additional roles in neurons and other cells including spermatids.

Monocular Diplopia Related to Asymmetric Corneal Topography After Laser in situ Keratomileusis

PURPOSE

To show a specific relationship between monocular diplopia and corneal refractive asymmetry after laser in situ keratomileusis (LASIK).

METHODS

One hundred thirty-eight eyes of 98 patients who underwent LASIK for myopia between -2.12 and -17.75 D were examined under room-lighted conditions. We examined 51 eyes at 2 weeks, 46 eyes at 3 months, 32 eyes at 6 months, and 9 eyes at 1 year after LASIK. We attempted to correlate the presence of monocular diplopia with their corneal topographical features.

RESULTS

Eight eyes of five patients (five eyes at 2 weeks, three eyes at 3 months after LASIK) produced symptoms of monocular diplopia. These symptomatic patients had a common corneal topographical feature caused by decentralized or inhomogeneous ablation. Every pupillary area in the patients' topographies contained steeper and flatter areas. The range of refractive power variation in these asymmetric areas was at least 1.50 D. The location of the secondary image correlated with the direction of the steeper area in all eight eyes. Pinhole viewing eliminated or reduced the prominence of secondary images in every case.

CONCLUSION

Monocular diplopia following LASIK appears to correlate with postoperative corneal refractive power variation inside the pupillary area, caused by decentralized or inhomogeneous ablation.

Generation of high curvature membranes mediated by direct endophilin bilayer interactions

Endophilin 1 is a presynaptically enriched protein which binds the GTPase dynamin and the polyphosphoinositide phosphatase synptojanin. Perturbation of endophilin function in cell-free systems and in a living synapse has implicated endophilin in endocytic vesicle budding (Ringstad, N., H. Gad, P. Low, G. Di Paolo, L. Brodin, O. Shupliakov, and P. De Camilli. 1999. Neuron. 24:143-154; Schmidt, A., M. Wolde, C. Thiele, W. Fest, H. Kratzin, A.V. Podtelejnikov, W. Witke, W.B. Huttner, and H.D. Soling. 1999. Nature. 401:133-141; Gad, H., N. Ringstad, P. Low, O. Kjaerulff, J. Gustafsson, M. Wenk, G. Di Paolo, Y. Nemoto, J. Crun, M.H. Ellisman, et al. 2000. Neuron. 27:301-312). Here, we show that purified endophilin can directly bind and evaginate lipid bilayers into narrow tubules similar in diameter to the neck of a clathrin-coated bud, providing new insight into the mechanisms through which endophilin may participate in membrane deformation and vesicle budding. This property of endophilin is independent of its putative lysophosphatydic acid acyl transferase activity, is mediated by its NH2-terminal region, and requires an amino acid stretch homologous to a corresponding region in amphiphysin, a protein previously shown to have similar effects on lipid bilayers (Takei, K., V.I. Slepnev, V. Haucke, and P. De Camilli. 1999. Nat. Cell Biol. 1:33-39). Endophilin cooligomerizes with dynamin rings on lipid tubules and inhibits dynamin's GTP-dependent vesiculating activity. Endophilin B, a protein with homology to endophilin 1, partially localizes to the Golgi complex and also deforms lipid bilayers into tubules, underscoring a potential role of endophilin family members in diverse tubulovesicular membrane-trafficking events in the cell.

Determination of S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]glutathione, a novel metabolite of L-histidine, in tissue extracts from sunlight-irradiated rat by capillary electrophoresis

Exposure of the skin to sunlight results in an increase in the content of epidermal urocanic acid, a key metabolite of L-histidine, and some portions of the metabolite penetrate into the body fluid. S-[2-Carboxy-1-(1H-imidazol-4-yl)ethyl]glutathione (GS(CIE)), an adduct of glutathione and urocanic acid, was proposed to be an origin of a urinary compound, S-[2-carboxy-1-(1 H-imidazol-4-yl)ethyl]-L-cysteine (Cys(CIE)). Various catabolites of Cys(CIE) were also isolated from human urine previously. However, no direct evidence to show the existence of GS(CIE) as a biological material had been found. By using capillary electrophoresis, the glutathione adduct has now been found in the extracts of rat tissues from the kidney, liver, skin and blood when the rat was kept under conditions of sunlight irradiation after the fur on the dorsal skin had been clipped. On the other hand, no or a trace of GS(CIE) was determined in rat tissue extracts when the animal was kept indoor in usual manner. The glutathione adduct was isolated from the kidney extract of the sunlight-irradiated rat using ion-exchangers and high-voltage paper electrophoresis, and determined by fast-atom-bombardment mass spectrometry. These results indicate that GS(CIE) formation actually occurs in the body and that the formation is accelerated by exposing the rat to sunlight irradiation. From these findings, we propose an alternative pathway of histidine metabolism which is initiated by the adduction of urocanic acid to glutathione to form GS(CIE) and terminates with the formation of the urinary compounds via Cys(CIE).

Differential cellular targets of Epstein-Barr virus (EBV) infection between acute EBV-associated hemophagocytic lymphohistiocytosis and chronic active EBV infection

Unusual Epstein-Barr virus (EBV) infection into T or natural killer cells plays a pivotal role in the pathogenesis of acute EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and chronic active EBV infection (CAEBV). The precise frequency and localization of EBV genome in lymphocyte subpopulations especially within T-cell subpopulations are unclear in these EBV-related disorders. This study analyzed the frequency of EBV-infected cells in circulating lymphocyte subpopulations from 4 patients with acute EBV-HLH and 4 with CAEBV. EBV- encoded small RNA-1 in situ hybridization examination of peripheral blood lymphocytes showed a significantly higher frequency of EBV-infected cells of 1.0% to 13.4% in EBV-HLH and 1.6% to 25.6% in CAEBV, respectively. The patterns of EBV infection in lymphocyte subpopulations were quite different between acute EBV-HLH and CAEBV. EBV infection was predominant in CD8(+) T cells in all EBV-HLH patients, whereas the dominant EBV-infected cell populations were non-CD8(+) lymphocyte subpopulations in CAEBV patients. Phenotypical analysis revealed that EBV-infected cell populations from both EBV-HLH and CAEBV were activated. There was no predominance of any EBV substrain of latent membrane protein-1, EBV-associated nuclear antigen (EBNA)-1, and EBNA-2 genes between the 2 abnormal EBV-associated disorders, and self-limited acute infectious mononucleosis. These results showing differential virus-cell interactions between acute EBV-HLH and CAEBV indicated different pathogenic mechanisms against EBV infection between the 2 EBV-associated diseases, which accounts for the difference in clinical manifestations between the 2 diseases.

Detection of species of the subgenus Leishmania parasites using polymerase chain reaction and southern blotting

In this study, an attempt was made to identify different Leishmania species by polymerase chain reaction (PCR). Fourteen Leishmania strains from stock were tested by PCR and Southern blotting. A pair of primers were employed that anneal to the kinetoplast DNA sequence conserved among subgenus Leishmania. Of the 14 Leishmania strains used in this study, six showed strong bands of approximately 170 bp, and all the positive strains belonged to the species of the subgenus Leishmania viz., Leishmania (Leishmania) garnhami, L. (L.) amazonensis, L. (L.) pifanoi, L. (L.) mexicana, L. (L.) chagasi, and L. (L.) major All the species belonging to the subgenus Viannia used in this study were negative by PCR. These results suggest that the primer pair may be useful for identification of the species belonging to the subgenus Leishmania of the New World as well as to distinguish subgenus Leishmania from subgenus Viannia.

Clathrin-mediated endocytosis: membrane factors pull the trigger

Clathrin-mediated endocytosis is a vesicular transport event involved in the internalization and recycling of receptors participating in signal transduction events and nutrient import as well as in the reformation of synaptic vesicles. Recent studies in vitro and in living cells have provided a number of new insights into the initial steps of clathrin-coated vesicle formation and the membrane factors involved in this process. The unexpected complexity of these interactions at the cytosol-membrane interface suggests that clathrin-coated vesicle assembly is a highly cooperative process occurring under tight regulatory control. In this review, we focus on the role of membrane proteins and lipids in the nucleation of clathrin-coated pits and provide a hypothetical model for the early steps in clathrin-mediated endocytosis.

The Arabidopsis AHK4 histidine kinase is a cytokinin-binding receptor that transduces cytokinin signals across the membrane

Common histidine-to-aspartate (His-->Asp) phosphorelay is a paradigm of signal transduction in both prokaryotes and eukaryotes for the propagation of certain environmental stimuli, in which histidine (His)-kinases play central roles as sensors for environmental signals. For the higher plant, Arabidopsis thaliana, it was recently suggested that the His-kinase (AHK4 / CRE1 / WOL) is a sensor for cytokinins, which are a class of plant hormones important for the regulation of cell division and differentiation. Interestingly, AHK4 is capable of functioning as a cytokinin sensor in the eubacterium, Escherichia coli (Suzuki et al. 2001, Plant Cell Physiol. 42: 107). Here we further show that AHK4 is a primary receptor that directly binds a variety of natural and synthetic cytokinins (e.g. not only N(6)-substituted aminopurines such as isopentenyl-adenine, trans-zeatin, benzyl-adenine, but also diphenylurea derivatives such as thidiazuron), in a highly specific manner (K(d) = 4.55+/-0.48x10(-9) M). AHK4 has a presumed extracellular domain, within which a single amino acid substitution (Thr-301 to Ile) was shown to result in loss of its ability to bind cytokinins. This particular mutation corresponds to the previously reported wol allele (wooden leg) that causes a striking phenotype defective in vascular morphogenesis. Collectively, evidence is presented that AHK4 and its homologues (AHK3 and possibly AHK2) are receptor kinases that can transduce cytokinin signals across the plasma membrane of A. thaliana.

Identification of genes encoding adenylate isopentenyltransferase, a cytokinin biosynthesis enzyme, in Arabidopsis thaliana

The initial step in the de novo biosynthesis of cytokinin in higher plants is the formation of isopentenyladenosine 5'-monophosphate (iPMP) from AMP and dimethylallylpyrophosphate (DMAPP), which is catalyzed by adenylate isopentenyltransferase (IPT). Although cytokinin is an essential hormone for growth and development, the nature of the enzyme for its biosynthesis in higher plants has not been identified. Herein, we describe the molecular cloning and biochemical identification of IPTs from Arabidopsis thaliana. Eight cDNAs encoding putative IPT, designated as AtIPT1 to AtIPT8, were picked up from A. thaliana. The Escherichia coli transformants expressing the recombinant proteins excreted cytokinin species into the culture medium except for that expressing AtIPT2 that is a putative tRNA IPT. A purified recombinant AtIPT1 catalyzed the formation of iPMP from DMAPP and AMP. These results indicate that the small multigene family contains both types of isopentenyltransferase, which could synthesize cytokinin and mature tRNA.

Transurethral holmium: YAG laser prostatectomy using a side-firing fiber for bladder outlet obstruction due to benign prostatic enlargement: urodynamic evaluation of surgical outcome

OBJECTIVES

To prospectively assess the efficacy of transurethral holmium (Ho):YAG laser prostatectomy using a side-firing fiber in patients with bladder outlet obstruction due to benign prostatic enlargement (BPE) from the standpoint of urodynamics.

METHODS

32 male patients with BPE aged 53-83 (mean 69.4) years were operated on. All patients, excluding 3 with urinary retention, were evaluated with the International Prostatic Symptom Score (IPSS), Quality of Life (QOL) score and uroflowmetry up to 12 months postoperatively, and a pressure/flow study was performed before and 3 months after the operation.

RESULTS

The total IPSS score, QOL score, average and maximum flow rates improved significantly (p<0.0001) at 12 months postoperatively. In the pressure/flow study, detrusor opening pressure, maximum detrusor pressure, detrusor pressure at maximum flow, minimum urethral opening pressure, and Abrams-Griffiths number decreased significantly (p<0.0001, p = 0.0001, p<0.0001, p = 0.0019 and p<0.0001, respectively) 3 months postoperatively. Detrusor instability disappeared in 12 of 17 patients and remained in 2.

CONCLUSIONS

Transurethral Ho:YAG laser prostatectomy was found to be effective for the treatment of bladder outlet obstruction due to BPE.

Physical and transcriptional map of a 311-kb segment of chromosome 18q21, a candidate lung tumor suppressor locus

Here, we report the complete genomic sequence and the characterization of the 311-kb region of 18q21, a candidate tumor suppressor locus containing a region of homozygous deletion in a lung cancer cell line, Ma29. This region contained two known genes, SMAD4 and ME2 (mitochondrial malate oxydoreductase), and two novel genes, D29 (deleted in Ma29 HGMW-approved symbol ELAC1), encoding an evolutionarily conserved protein, and B29 (beside the Ma29 deletion HGMW-approved symbol C18orf3), with no significant homology to any known genes. The deleted DNA segment in Ma29, which was estimated to be 195 kb in size, included all the coding exons of ME2 and D29, but not the coding exons of SMAD4 and B29. The deleted region also included exon 0, a 5'-noncoding exon, of SMAD4, and the expression of SMAD4 was greatly reduced in Ma29 cells. Mutations of SMAD4 and D29 were detected in 1 of 45 lung cancer cell lines examined, while those of ME2 and B29 were not detected, indicating that these four genes are not major targets for 18q21 deletions. The physical and transcriptional map constructed in this study will provide basic information for the identification of a tumor suppressor gene(s) at 18q21 involved in lung carcinogenesis.

Ultrastructural fragility and type IV collagen abnormality of the anterior lens capsules in a patient with Alport syndrome

PURPOSE

To investigate ultrastructural and immunohistological abnormalities of the lens capsules in a patient with Alport syndrome.

METHODS

Two anterior lens capsules were obtained at phacoemulsification from a 43-year-old female patient with bilateral lenticonus who was affected by Alport syndrome. The right capsule was examined by transmission electron microscopy and the left capsule was stained with two monoclonal antibodies against the triple-helical domains of type IV collagen alpha2 and alpha5 chains.

RESULTS

Numerous vertical dehiscences with many disrupted interdigitations were observed in the right anterior lens capsule. Decreased reactivity of monoclonal antibodies against type IV collagen alpha5 chain and normal reactivity against the alpha2 chain were shown in the left anterior lens capsule.

CONCLUSION

The ultrastructural fragility of the anterior lens capsules in this patient with Alport syndrome appears to be associated with the abnormality of the type IV collagen molecules including the alpha5 chain.

Nitrogen-dependent accumulation of cytokinins in root and the translocation to leaf: implication of cytokinin species that induces gene expression of maize response regulator

We have described the spatial and temporal accumulation pattern of various cytokinin species in roots, xylem sap and leaves during the resupply of nitrogen in maize. Upon addition of nitrate to nitrogen-depleted maize plants, isopentenyladenosine-5'-monophosphate (iPMP) started to accumulate in roots within 1 h preceding accumulation of trans-zeatin riboside-5'-monophosphate (ZMP), trans-zeatin riboside (ZR) and trans-zeatin (Z). In the xylem flow, both exudation rate of xylem sap and the concentration of the cytokinins increased, and ZR was the dominant species in the sap. In leaf tissue, the accumulation level of Z, which was the dominant form, started to increase 4 h after nitrate resupply to plants and the level was maintained for at least 24 h. Administration of a near physiological concentration of Z, ZR or ZMP (Z-type cytokinins) to detached leaves induced the accumulation of ZmRR1 transcript, that encode maize response regulators, but administration of isopentenyladenine, isopentenyladenosine or iPMP did not. These results strongly suggest that cytokinins are transported across the roots to shoots in response to nitrogen availability, and that, most probably, Z-type cytokinin(s), trigger the induction of ZmRR1.

Immunohistochemical and statistical studies on the islets of Langerhans pancreas in autopsied patients after gastrectomy

We describe in detail the pathologic features of the islets of Langerhans in specimens of the pancreas from 75 autopsy specimens of patients who underwent gastrectomy and compare them with specimens from 22 patients not having gastrectomy with respect to the duration of the postoperative period and the operative procedure. In comparison with the control group, the islets of Langerhans from the gastrectomy patients showed hyperplasia and increased numbers of endocrine cells within 5 years of gastrectomy but atrophy and decreased numbers of endocrine cells thereafter. These changes are compatible with anti-insulin immunoreactivity (B-cells) in the islets of Langerhans, where B-cell counts correlated with the area of the islets. The proliferating cell nuclear antigen (PCNA)-positive cell ratio in the islets was higher during the early phase after gastrectomy, whereas the apoptotic cell ratio was not affected by the time after gastrectomy. Hyalinization of the islets of Langerhans was first recognized after 5 years postoperatively, and the percentage of hyalinization gradually increased. Amylin deposits, detected by immunostaining, increased progressively in the islets in relation to the duration of postoperative period, correlating inversely with B-cell count and PCNA positivity. These histologic changes suggest that B cells proliferated secondary to oxyhyperglycemia in the early phase after gastrectomy followed by the state of waste, finally resulting in atrophy and amylin deposits, which led to hypofunction of the islets of Langerhans with resultant glucose intolerance. HUM PATHOL 31:1368-1376.

Detection of telomerase activity in biopsy specimens for diagnosis of biliary tract cancers

BACKGROUND

Telomerase activity is detectable in more than 85% of primary cancers. We determined telomerase activity in biopsy specimens obtained from biliary tract cancers to evaluate the clinical application of telomerase activity detection in combination with p53 immunostaining and routine histologic examination.

METHODS

Biopsy specimens obtained during percutaneous transhepatic cholangioscopy from 13 patients with cholangiocarcinoma, 3 patients with gallbladder carcinoma, and 4 patients with intrahepatic bile duct stones were evaluated by routine histologic examination, p53 immunostaining, and telomerase activity. Semiquantitative determination of telomerase activity was performed using a fluorescence-based telomeric repeat amplification protocol.

RESULTS

Thirteen of 16 specimens of malignant tissue had detectable telomerase activity, whereas no specimen of nonmalignant tissue had detectable telomerase activity. A p53 overexpression was recognized by immunostaining in 9 of 16 samples with cancers. Combining both telomerase activity and p53 overexpression resulted in the detection of all cancer with a sensitivity of 100%. There were no false-positive results by either modality (specificity 100%).

CONCLUSIONS

The detection of telomerase activity in biopsy specimens and p53 overexpression in combination with routine histologic examination may improve the diagnosis of biliary tract cancers. (Gastrointest Endosc 2000;52:380-6).

Histopathologic and immunohistochemical studies on the mechanism of interlobular fibrosis of the pancreas

OBJECTIVE

To elucidate the mechanism of interlobular fibrosis of the pancreas, which is categorized as chronic alcoholic pancreatitis.

METHODS

Forty pancreatic tissue samples from patients with ampullary carcinomas, which cause various degrees of stricture of the main pancreatic duct, and 20 patients with chronic alcoholic pancreatitis were studied histopathologically and immunohistochemically.

RESULTS

Fibrosis was observed in 23 of 40 patients with ampullary carcinomas and was classified into 3 categories: mild changes (10 cases), moderate changes (9 cases), and marked changes (4 cases). In the mild change cases, mild fibrosis was diffusely distributed in the interlobular areas, with scant immunoreactivity of anti-alpha-smooth muscle actin (alpha-SMA) and an expansive lobular appearance, whereas moderate and marked change cases showed interlobular and intralobular fibrosis with marked anti-alpha-SMA immunoreactivity and lobular atrophy. By quantitative analysis, the mild change cases showed both higher MIB1-positive and lower apoptotic acinar cell ratios than those of moderate and marked changes. Anti-alpha-SMA immunoreactivity in the patients with chronic alcoholic pancreatitis was found in interlobular fibrosis. Hence, mild changes in cases of ampullary carcinomas had histologic findings similar to chronic alcoholic pancreatitis, except for excessive fibrosis cases with patchy distribution.

CONCLUSION

Incomplete obstruction of the main pancreatic duct caused the beginning of interlobular fibrosis, which is categorized as chronic alcoholic pancreatitis.

Oral calcium supplement decreases urinary oxalate excretion in patients with enteric hyperoxaluria

We studied the effect of oral calcium supplementation in patients with enteric hyperoxaluria. Three patients with renal stone events following ileal resection were given oral calcium supplement. One of the three patients was put on a low-fat diet. The treatment reduced urinary oxalate excretion to the normal range. Subsequently, 2 patients reduced the dose of calcium supplementation at their own discretion and consequently developed renal stones again together with hyperoxaluria. Based on these observations, we believe that an adequate dose of calcium can normalize urinary oxalate excretion.

Mutation and expression of the DCC gene in human lung cancer

Chromosome 18q is frequently deleted in lung cancers, and a common region of 18q deletions was mapped to chromosome 18q21. Since the DCC candidate tumor suppressor gene has been mapped in this region, mutation and expression of the DCC gene were examined in 46 lung cancer cell lines, consisting of 14 small cell lung carcinomas (SCLCs) and 32 non-small cell lung carcinomas (NSCLCs), to elucidate the pathogenetic significance of DCC alterations in human lung carcinogenesis. A heterozygous missense mutation was detected in a NSCLC cell line, Ma26, while homozygous deletion was not detected in any of the cell lines. The DCC gene was expressed in 11 (24%) of the 46 cell lines, and the incidence of DCC expression was significantly higher in SCLCs (7/14, 50%) than in NSCLCs (4/32, 13%) (P = .01, Fisher's exact test). Therefore, genetic alterations of DCC are infrequent; however, the levels of DCC expression vary among lung cancer cells, in particular, between SCLCs and NSCLCs. The present result does not implicate DCC as a specific mutational target of 18q deletions in human lung cancer; however, it suggests that DCC is a potential target of inactivation by genetic defects including intron or promoter mutations and/or epigenetic alterations. The present result also suggests that DCC expression is associated with some properties of SCLCs, such as a neuroendocrine (NE) feature.

[A case of autosomal recessive juvenile parkinsonism (AR-JP) with onset at the age of 6 years]

We report a 26-year-old woman with autosomal recessive juvenile parkinsonism (AR-JP). Her parents made consanguineous marriage. The disease started with dystonic posture of legs 20 years prior to the admission (6 years old). The equinovarus foot appeared at 9 years old and parkinsonism gradually developed. These symptoms were remarkably improved after sleep. Levodopa was effective on her parkinsonian symptoms. However, the response to levodopa gradually reduced. On admission, she presented with a masked face, marked rigidity, moderate retropulsion, postural tremor in the upper limbs and mild hyperreflexia in the lower limbs. Mutational analysis revealed homozygous deletion of exon 4 in perkin gene. This patient has youngest age of onset for ARJP to our knowledge.

Videokeratography after excimer laser in situ keratomileusis for myopia

OBJECTIVE

The purpose of this study was to define qualitative patterns of videokeratography after excimer laser in situ keratomileusis (LASIK) for myopia and to identify associations of videokeratography patterns with clinical variables.

DESIGN

Single-center, retrospective, cohort study.

PARTICIPANTS

One hundred twenty-six eyes of 68 patients with myopia who desired surgical correction of myopia ranging from -1.50 to -8.80 diopters.

INTERVENTION

Myopia was corrected with LASIK using a Summit OmniMed/Apex excimer laser. Computer-assisted videokeratography data were acquired at 3 months after primary LASIK, and associations of videokeratography pattern with clinical variable were assessed.

MAIN OUTCOME MEASURES

Seven subgroup ablation zone patterns were characterized using tangential curvature maps; these subgroups were combined into pooled symmetric and asymmetric groups. Associations with age, attempted correction, single-zone or multizone ablation, postoperative uncorrected and spectacle-corrected visual acuity, predictability, astigmatism, corneal uniformity, glare disability, and contrast sensitivity were analyzed.

RESULTS

Thirty-two eyes (25.4%) showed a uniform pattern, 14 eyes (11.1%) showed a bow-tie pattern, 22 eyes (17.5%) showed a peninsula pattern, 22 eyes (17.5%) showed a semicircular pattern, 22 eyes (17.5%) showed an off-center blue spot pattern, 10 eyes (7.9%) showed an irregular pattern, and 4 eyes (3.2%) showed a central island pattern. Spectacle-corrected visual acuity, astigmatism, corneal uniformity, glare disability, and contrast sensitivity were significantly related to videokeratography pattern, although the difference among videokeratography groups was clinically small. Age, attempted correction, single- or multizone ablation, and postoperative uncorrected visual acuity and predictability were not predictive of videokeratography pattern.

CONCLUSIONS

Most eyes in this study had an asymmetric videokeratography pattern 3 months after LASIK. Small but statistically significant differences were identified among the videokeratography patterns that potentially may affect postoperative quality of vision.

[Acute myocardial infarction in elderly patients: medical and social problems]

The number of elderly patients with acute myocardial infarction has been increasing. However, the choice of treatment remains controversial. Medical records of 310 consecutive patients with acute myocardial infarction were reviewed. Two retrospective analyses were performed. 1) Patients were divided into the elderly group(70 years or more) and the younger group(under 70 years). In-hospital course and outcome were compared. 2) Pre-hospital performance status and living status were reviewed in the elderly group. Acute phase reperfusion therapy was performed in fewer patients in the elderly group(60.8% vs 71.9%, p < 0.01). The difference was most pronounced in cases of direct coronary angioplasty(28.6% vs 54.7%, p < 0.05). As a result, the rate of reperfusion success(74.8% vs 86.8%, p < 0.01) was lower in the elderly group. Moreover, the rates of in-hospital death(23.6% vs 6.8%, p < 0.005), pulmonary edema(20.3% vs 10.8%, p < 0.05), cardiogenic shock(11.9% vs 6.0%, p < 0.005), pneumonia(17.3% vs 3.0%, p < 0.005), and delirium(29.4% vs 12.0%, p < 0.001) were higher in the elderly group. Five patients in the elderly group and 3 patients in the younger group required rehabilitation because of worsened performance status. Six of them were non-reperfused patients. Elderly patients considered likely to become bed-ridden because of pre-existing physical disability at admission accounted for 28.9% of the total. Moreover, many elderly patients had poor support systems (8.4% were living alone, 21.0% were living only with their spouse or a child, 30.1% were widows or widowers). These results show that a lower acute phase reperfusion rate(especially angioplasty) resulted in a poor prognosis and worse performance status in elderly patients. Also 30% of patients were not good candidates for conventional treatment because of delirium, and that self-help in daily life is a fundamental goal for most elderly patients. Rapid and simple acute phase reperfusion, subsequent immediate mobilization, and early discharge are recommended for elderly patients with acute myocardial infarction.

Nuclear cyclin D1 overexpression is a critical event associated with cell proliferation and invasive growth in gallbladder carcinogenesis

Cyclin D1 overexpression is remarkably frequent in several human carcinomas and is believed to be a critical event in oncogenesis. We examined cyclin D1 expression, p53 expression, and the Ki-67 labeling index by immunostaining in human gallbladder mucosa in conditions varying from normal to malignant tissue. We also examined K-ras codon 12 mutations in these tissues with a two-step polymerase chain reaction. Nuclear cyclin D1 overexpression was observed in 48% of carcinomas occurring independently of adenoma, but not in adenomas, carcinomas arising in adenomas, or nonneoplastic lesions. Cytoplasmic cyclin D1 overexpression was observed in about 15% of abnormal specimens, irrespective of the type of epithelial abnormality. Carcinomas showing nuclear cyclin D1 overexpression had significantly higher Ki-67 labeling indexes than those with no overexpression. Moderately to poorly differentiated adenocarcinomas showed a higher incidence of nuclear cyclin D1 overexpression than papillary to well differentiated carcinomas. Specimens with cyclin D1 overexpression showed a high incidence of lymph permeation, venous permeation, and lymph node metastasis. We conclude that nuclear cyclin D1 overexpression is a critical event importantly associated with cell proliferation and invasive growth in gallbladder carcinogenesis, and that cyclin D1 immunostaining may become a useful marker for evaluating gallbladder carcinomas.