Nucleotide sequencing analysis of the 146-kilobase segment around the IkBL and MICA genes at the centromeric end of the HLA class I region

The biomechanics of medialization laryngoplasty are not well understood. An excised canine larynx model was used to test the effects of various sized silicon implants. The vocal fold length, position, and tension were measured. Medialization laryngoplasty did not affect vocal fold length. At the mid-membranous vocal fold, larger shims resulted in greater medialization and tension. Medialization laryngoplasty neither medialized nor stiffened the vocal process to resist lateralizing forces. We conclude that medialization laryngoplasty provides bulk and support for defects of the membranous region of the vocal fold, but does not appear to close a posterior glottal gap. The selection of a surgical procedure to treat glottal incompetence should take into account the unique biomechanical properties of the anterior (membranous vocal folds) and posterior (cartilaginous portion) glottis.     

A sole del(15q) anomaly in post-myelodysplasia acute myeloid leukemia

We report the second case of post-myelodysplasia acute myeloid leukemia (post-MDS AML) with a sole chromosome change del(15q). This anomaly is rarely seen. To our knowledge, only seven cases so far have been reported in human neoplasias, including one case each of acute myeloid leukemia (AML), acute lymphoid leukemia, post myelodysplasia AML, myelodysplastic syndrome, myelofibrosis, macroglobulinemia, Hodgkin's lymphoma and uterine leiomyoma. This case suggests that del(15q) is related to lympho-myeloproliferative disorders. Moreover, we speculate that certain oncogene(s) located on 15q might have some role in the progression of the disease, since the del(15q) anomaly appeared only in the AML phase in this case.     

Raman amplification of 1.50-µm laser diode light in a low fiber loss region

Raman amplification utilizing the second Stokes line of 1.32-μm Nd:YAG laser light in a single-mode silica fiber was observed. Raman gains of 24 dB have been obtained for 1.50-μm laser diode light in the low-loss region. In addition, the signal-to-noise characteristics of Raman amplification using the second Stokes line was investigated. As a result, it became clear that theS/Nratio was inferior to that in 1st Stokes line by about one order of magnitude.     

Ca2+ in the dense tubules: a model of platelet Ca2+ load

In this work, we explored the relationship between the freely exchangeable Ca2+ (FECa2+) in the dense tubules (DT) and the sarco(endo)plasmic reticulum (SER) Ca2+-ATPase (SERCA) in circulating human platelets and examined the relationship between blood pressure (BP) and these platelet parameters. Studying platelets from 32 healthy men, we showed that the maximal reaction velocity (Vmax) of the SERCA significantly correlated with FECa2+ in the DT and with the protein expressions of SERCA 2 and 3. BP positively correlated with both the Vmax of the SERCA (r=.462, P=.010) and the FECa2+ sequestered in the DT (r=.492, P=.005). The relationships between these platelet Ca2+ parameters and BP were in part confounded by increased levels of serum triglycerides and diminished HDL cholesterol with a higher BP. No correlation was observed between the resting cytosolic Ca2+ and BP. Collectively, these findings indicate that (1) an increase in the cellular Ca2+ load in platelets is expressed by a higher activity of the SERCA and an increase in the expressions of SERCA 2 and 3 proteins, coupled with an increase in the FECa2+ in the DT, and (2) a higher BP is associated with an increase in platelet Ca2+ load in human beings, expressed by a rise in the FECa2+ in the DT and the upregulation of SERCA activity.     

Allelic diversity in the merozoite surface protein-1 and epidemiology of multiple-clone Plasmodium falciparum infections in northern Tanzania

Allelic diversity in the merozoite surface protein-1 (MSP-1) of Plasmodium falciparum, a major malaria vaccine candidate, was examined in clinical isolates from holoendemic northern Tanzania. The variable blocks 2, 4a, 4b, 6, and 10 of the MSP-1 gene were typed by allelic type-specific polymerase chain reaction. Twenty-four possible MSP-1 gene types were defined as unique combinations of allelic types detected in each variable block. Thirteen gene types were identified, and 187 P. falciparum populations were fully typed among 79 isolates. In contrast with recent findings in Vietnam, we were unable to detect nonrandom associations between allelic types in the typed variable blocks. Most patients (60%) harbored more than 1 genetically distinct parasite population (average: 2.37 populations per isolate) and, in 1 patient, 6 different versions of this single-copy gene were found. Statistical analysis suggests that parasites carrying different MSP-1 gene types are not independently distributed in the host population. The epidemiological consequences of these findings are discussed.     

Genetic analysis of the chitinase system of Serratia marcescens 2170

To carry out a genetic analysis of the degradation and utilization of chitin by Serratia marcescens 2170, various Tn5 insertion mutants with characteristic defects in chitinase production were isolated and partially characterized. Prior to the isolation of the mutants, proteins secreted into culture medium in the presence of chitin were analyzed. Four chitinases, A, B, C1, and C2, among other proteins, were detected in the culture supernatant of S. marcescens 2170. All four chitinases and a 21-kDa protein (CBP21) lacking chitinase activity showed chitin binding activity. Cloning and sequencing analysis of the genes encoding chitinases A and B of strain 2170 revealed extensive similarities to those of other strains of S. marcescens described previously. Tn5 insertion mutagenesis of strain 2170 was carried out, and mutants which formed altered clearing zones of colloidal chitin were selected. The obtained mutants were divided into five classes as follows: mutants with (i) no clearing zones, (ii) fuzzy clearing zones, (iii) large clearing zones, (iv) delayed clearing zones, and (v) small clearing zones. Preliminary characterization suggested that some of these mutants have defects in chitinase excretion, a negatively regulating mechanism of chitinase gene expression, an essential factor for chitinase gene expression, and a structural gene for a particular chitinase. These mutants could allow researchers to identify the genes involved in the degradation and utilization of chitin by S. marcescens 2170.     

Effect of applied voltage frequency on swarming pulsive microdischarges in closed voids

The extinction of the partial discharge (PD) pulse has frequently been observed in an epoxy specimen with a closed void during voltage endurance tests using a CIGRE Method-II electrode. The individual discharge pulse becomes so small that the discharges cannot be detected by conventional pulse detection methods. Such discharges are known as “swarming pulsive microdischarges” (SPMD). In this paper, the SPMD characteristics are investigated by varying the frequency of the applied voltage from 0.1 to 240 Hz. As a result, the SPMD are found to occur less frequently as the frequency is lowered. To seek this cause, one-shot voltages were applied repeatedly at constant intervals. By varying the interval from 0.02 to 100 s, the PD off an electrically aged specimen was measured. It was revealed that the discharge magnitude increases as the interval becomes longer. The onset of SPMD was found to depend on the preceding discharge. The results explain the reason why swarming is harder to occur at lower frequency with a longer discharge interval. Hence, in the conventional pulse detection, it is useful to employ the very low frequency for diagnosis of machine insulation containing enclosed voids.     

Nonlinear phase distortion and its compensation in l.e.d. direct modulation

Differential phase distortion of the light-emitting diode is measured and analysed. An effective technique is proposed to compensate the d.p. distortion. An experimental result shows that 2.8° d.p. distortion has been reduced to within 1°.     

Wear of some F.C.C. metals during unlubricated sliding Part III: A mechanical aspect of wear

The relations between the size of wear fragments and the sliding velocity or normal load were studied from a mechanical point of view for the unlubricated wear of nickel. It was found that the size of mean wear fragments has a definite quantitative correlation with the thickness of the plastically deformed substrate layer, irrespective of the experimental conditions. The thickness of the deformed layer is determined by the actual forces working on real contact points, which are dependent on the dynamic properties of the specific sliding system. These mechanical factors govern wear-velocity and wear-normal load characteristics.