Clinical efficacy of autogenous cancellous bone and fibroblast growth factor 2 combined with frozen allografts in femoral nonunion fractures.

OBJECTIVES: To evaluate the efficacy of cortical allograft and fibroblast growth factor 2 (FGF-2)-impregnated autogenous cancellous bone in nonunion fracture repair in dogs. METHODS: From January 2000 to August 2010, seven dogs underwent cortical allograft and FGF-2-impregnated autogenous cancellous bone implantation for treatment of a femoral nonunion following fracture. Radiographic images were used to assess healing. RESULTS: The average length of the implanted cortical allograft was 29.1 ± 4.4 mm. A significant improvement in the postoperative percentage of femoral shortening was observed with the experimental treatment, from 85.2 ± 8.2% to 95.0 ± 4.8%. Using radiographic scoring, we analysed the process of bone remodelling. At three months post-surgery, the proximal and distal fracture lines had begun to disappear, and a complete absence was observed after six months. Bacterial infection was detected in two of the seven cases. CLINICAL SIGNIFICANCE: The findings of our study suggest that the combination of cortical allografts with FGF-2 impregnated cancellous autograft may be useful in cases of diaphyseal fracture non-union. The disappearance of the fracture line in dogs with nonunion was recognized at the same phase as the report in which healing process of allograft was evaluated in the experimental ostectomy model using the normal dog.

The effect of angiotensin-converting enzyme inhibitors of left atrial pressure in dogs with mitral valve regurgitation.

BACKGROUND: Despite many epidemiological reports concerning the efficacy of angiotensin-converting enzyme (ACE) inhibitors in dogs with mitral regurgitation (MR), the hemodynamic effects of ACE inhibitor administration have not been fully evaluated. OBJECTIVES: To document left atrial pressure (LAP) in dogs with MR administered ACE inhibitors, in order to obtain interesting information about daily LAP changes with administration of ACE inhibitors. ANIMALS: Five healthy Beagle dogs weighing 9.8 to 14.2 kg (2 males and 3 females; aged 2 years). METHODS: Experimental, crossover, and interventional study. Chordae tendineae rupture was induced, and a radiotelemetry transmitter catheter was inserted into the left atrium. LAP was recorded for 72 consecutive hours during which each of 3 ACE inhibitors--nalapril (0.5 mg/kg/d), temocapril (0.1 mg/kg/d), and alacepril (3.0 mg/kg/d)--were administered in a crossover study. RESULTS: Averaged diurnal LAP was significantly, but slightly reduced by alacepril (P = .03, 19.03 +/- 3.01-18.24 +/- 3.07 mmHg). The nightly drops in LAP caused by alacepril and enalapril were significantly higher than the daily drops (P = .03, -0.98 +/- 0.19 to -0.07 +/- 0.25 mmHg, and P = .03, -0.54 +/- 0.21-0.02 +/- 0.17 mmHg, respectively), despite the fact that the oral administrations were given in the morning. Systolic blood pressure (122.7 +/- 14.4-117.4 +/- 13.1 mmHg, P = .04) and systemic vascular resistance (5800 +/- 2685-5144 +/- 2077 dyne x s/cm5, P = .03) were decreased by ACE inhibitors. CONCLUSIONS AND CLINICAL IMPORTANCE: ACE inhibitors decrease LAP minimally, despite reductions in left ventricular afterload. ACE inhibitors should not be used to decrease LAP.

Laser tunnel ionization from multiple orbitals in HCl.

Tunneling, one of the most striking manifestations of quantum mechanics, influences the electronic structure of many molecules and solids and is responsible for radioactive decay. Much of the interaction of intense light pulses with matter commences with electrons tunneling from atoms or molecules to the continuum. Until recently, this starting point was assumed to be the highest occupied orbital of a given system. We have now observed tunneling from a lower-lying state in hydrogen chloride (HCl). Analyzing two independent experimental observables allowed us to isolate (via fragment ions), identify (via molecular frame photoelectron angular distributions), and, with the help of ab initio simulations, quantify the contribution of lower-lying orbitals to the total and angle-dependent tunneling current of the molecule. Our results bolster the emerging tenet that the coherent interaction between different orbitals--which can amplify the impact of lower orbitals--must be considered in tunneling processes.

Angular tunneling ionization probability of fixed-in-space H2 molecules in intense laser pulses.

We propose a new approach to obtain molecular frame photoelectron angular distributions from molecules ionized by intense laser pulses. With our method we study the angular tunnel ionization probability of H2 at a wavelength of 800 nm over an intensity range of 2-4.5 x 10(14) W/cm2. We find an anisotropy that is stronger than predicted by any existing model. To explain the observed anisotropy and its strong intensity dependence we develop an analytical model in the framework of the strong-field approximation. It expresses molecular ionization as a product of atomic ionization rate and a Fourier transform of the highest occupied molecular orbital filtered by the strong-field ionization process.

Expression of inflammatory mediators in the otitis media induced by Helicobacter pylori antigen in mice.

Helicobacter pylori is a Gram-negative bacterium that is recognized as one of the key factors in gastric diseases such as gastritis, peptic ulcer and gastric cancer. Recent studies have shown relationships between H. pylori and extra-digestive diseases, and the presence of H. pylori in the middle ear and upper respiratory tract has been reported. However, the role of H. pylori in middle ear disease remains unclear. The present study demonstrated that H. pylori whole-cell protein directly induces macrophage migration inhibitory factor, macrophage inflammatory protein 2, interleukin 1 beta and tumor necrosis factor alpha in middle ear epithelium in mice, and severe proliferation of inflammatory cells was observed in middle ear cavity inoculated with H. pylori whole-cell protein. In addition, trans-tympanic injection of macrophage migration inhibitory factor up-regulated expression of macrophage inflammatory protein 2 in the middle ear. These findings indicate that H. pylori infection causes immunological inflammation in middle ear epithelium, and H. pylori may play a significant role in otitis media.

Structural diversity and evolution of the Rf-1 locus in the genus Oryza.

The Rf-1 locus in rice is agriculturally important as it restores fertility in plants with BT-type cytoplasmic male sterility (CMS). The Rf-1 locus contains several duplicated copies of the gene responsible for restoration of fertility. We analyzed the genomic structure of the Rf-1 locus in the genus Oryza to clarify the structural diversity and evolution of the locus. We identified six genes (Rf-1A to Rf-1F) with homology to Rf-1 at this locus in Oryza species with an AA genome. The Rf-1 locus structures in the rice accessions examined were very complex and fell into at least six classification types. The nucleotide sequences of the duplicated genes and their flanking regions were highly conserved suggesting that the complex Rf-1 locus structures were produced by homologous recombination between the duplicated genes. The fact that complex Rf-1 locus structures were common to Oryza species that have evolved independently indicates that a duplication of the ancestral Rf-1 gene occurred early in rice evolution and that homologous recombination resulted in the diversification of Rf-1 locus structures. Additionally, the amino acid sequences of each duplicated gene were conserved between species. This suggests that the duplicated genes in the Rf-1 locus may have divergent functions and may act by controlling mitochondrial gene expression in rice as occurs in the restoration of CMS.

Environmental assessment of mercury dispersion, transformation and bioavailability in the Lake Victoria Goldfields, Tanzania.

Environmental dispersion and transformation of mercury discharged from gold mining operations has been investigated in field and laboratory studies in order to provide better understanding of the degree of mercury (Hg) pollution and bioavailability in the Lake Victoria goldfields (LVGF) ecosystems. This paper reviews results already published elsewhere and presents additional data on Hg dynamics in the LVGF. Studies conducted at the Mugusu and Rwamagaza artisanal mines indicated different degrees of Hg contamination and dispersion in environmental matrices. Mercury concentration in contaminated river sediments near the Mugusu mine varied from 6.0 to 0.5 mg/kg on a dry weight basis. The highest Hg contamination levels (165-232 mg/kg) were associated with mine tailings at the Rwamagaza mine. Mercury concentrations in fish representing different dietary habits on the southwestern shore of Lake Victoria at the Nungwe Bay were very low (2-35 microg/kg) and thought to represent background levels. These and other results suggested that the use of Hg in gold extraction in the LVGF has not caused high Hg levels in lake fish. The study of Hg in lichens showed Parmelia lichen to be an effective bioindicator for atmospheric Hg contamination due to Hg emissions from gold-amalgam firing and purification operations. The Hg levels in the lichens around the Mugusu mine ranged from 3.1 to 0.1 microg/g; the highest levels were recorded in the lichens sampled close to gold-amalgam processing sites. The regional background level in the Parmelia lichen was 0.05-0.10 microg/g, with a mean level of 0.07 microg/g. Studies of Hg transformation in the mine tailings revealed unexpectedly high methylmercury (MeHg) levels in the tailings (629-710 ng/g), which indicated that oxidation and methylation of metallic Hg in the tailings occurred at significant levels under tropical conditions. Re-equilibration of the tailings with freshwater (FW) indicated the MeHg was firmly bound in the tailings and therefore very little MeHg was released to the water column (0.2-1.5 ng/L). The methylation of Hg in tropical loamy clay soil contaminated with HgCl(2) (5 mg Hg/kg) yielded MeHg concentrations of 11 and 14 ng/g when inundated with seawater and FW, respectively, for 4 weeks. Little MeHg was transferred from the soil to the equilibrated water (< or = 0.4 ng/L). Atmospheric exposure of the soil pre-inundated with FW resulted in net degradation of MeHg during the 1st week of exposure, followed by net production and accumulation of MeHg in the soil (up to 15.5 ng/g) during atmospheric desiccation. Mercury uptake by fish from the Hg(0)-contaminated aquatic sediment-tailings system in the aquarium experiment was found to be low, suggesting the low availability of MeHg for bioaccumulation in the system. These and other results provide useful insights into Hg transformation, mobility and bioavailability in tropical aquatic systems affected by Hg pollution from gold mining operations.

Genomic distribution of MITEs in barley determined by MITE-AFLP mapping.

Miniature inverted-repeat transposable elements (MITEs) represent a large superfamily of transposons that are moderately to highly repetitive and frequently found near or within plant genes. To elucidate the organization of MITEs in the barley genome, MITEs were integrated into the genetic map of barley. In this report, we describe the use of MITEs in amplified fragment length polymorphism (AFLP) mapping, and demonstrate their superiority over conventional AFLP mapping. Barley MITEs include members of the Stowaway, Barfly, and Pangrangja families. By amplifying the flanking sequences of these MITEs, a total of 214 loci were mapped from a population of 93 doubled-haploid segregating individuals between Hordeum vulgare ssp. vulgare and H. vulgare ssp. spontaneum. The 214 MITE-AFLP and 40 anchor simple sequence repeat (SSR) loci were distributed on 7 linkage groups, covering a total map distance of 1 165 cM. The average marker density on each chromosome ranged between 3.4 and 9.6 cM per locus. Only 1 MITE-based locus was frequently found to be associated with MITE loci from the same family, resulting in clusters in chromosomal subregions. In barley, it will be possible to cover the entire genome with a limited set of MITE-based primers and to build highly dense maps of specific regions.

Positional cloning of the rice Rf-1 gene, a restorer of BT-type cytoplasmic male sterility that encodes a mitochondria-targeting PPR protein.

The combination of cytoplasmic male sterility (CMS) in one parent and a restorer gene ( Rf) to restore fertility in another are indispensable for the development of hybrid varieties. We have found a rice Rf-1 gene that restores BT-type CMS by applying a positional cloning strategy. Using linkage analysis in combination with 6,104 BC(1)F(3) progeny derived from a cross between two near-isogenic lines (NILs) differing only at the Rf-1 locus, we delimited the Rf-1 gene to a 22.4-kb region in the rice genome. Duplicate open reading frames ( Rf-1A and Rf-1B) with a pentatricopeptide (PPR) motif were found in this region. Since several insertions and/or deletions were found in the regions corresponding to both the Rf-1A and Rf-1B genes in the maintainer's allele, they may have lost their function. Rf-1A protein had a mitochondria-targeting signal, whereas Rf-1B did not. The Rf-1B gene encoded a shorter polypeptide that was determined by a premature stop codon. Based on the function of the Rf-1 gene, its product is expected to target mitochondria and may process the transcript from an atp6/orf79 region in the mitochondrial genome. Since the Rf-1A gene encodes a 791-amino acid protein with a signal targeting mitochondria and has 16 repeats of the PPR motif, we concluded that Rf-1A is the Rf-1 gene. Nine duplications of Rf-1A homologs were found around the Rf-1 locus in the Nipponbare genome. However, while some of them encoded proteins with the PPR motif, they do not restore BT-type CMS based on the lack of co-segregation with the restoration phenotype. These duplicates may have played diversified roles in RNA processing and/or recombination in mitochondria during the co-evolution of these genes and the mitochondrial genome.

Total mercury and methylmercury levels in fish from hydroelectric reservoirs in Tanzania.

Total mercury (THg) and methylmercury (MeHg) levels have been determined in fish species representing various tropic levels in four major hydroelectric reservoirs (Mtera, Kidatu, Hale-Pangani, Nyumba ya Mungu) located in two distinct geographical areas in Tanzania. The Mtera and Kidatu reservoirs are located along the Great Ruaha River drainage basin in the southern central part of the country while the other reservoirs are located within the Pangani River basin in the north eastern part of Tanzania. Fish mercury levels ranged from 5 to 143 microg/kg (mean 40 microg/kg wet weight) in the Mtera Reservoir, and from 7 to 119 microg/kg (mean 21 microg/kg) in the Kidatu Reservoir downstream of the Great Ruaha River. The lowest THg levels, in the range 1-10 microg/kg (mean 5 microg/kg), were found in fish from the Nyumba ya Mungu (NyM) Reservoir, which is one of the oldest reservoirs in the country. Fish mercury levels in the Pangani and Hale mini-reservoirs, downstream of the NyM Reservoir, were in the order of 3-263 microg/kg, with an average level of 21 microg/kg. These THg levels are among the lowest to be reported in freshwater fish from hydroelectric reservoirs. Approximately 56-100% of the total mercury in the fish was methylmercury. Herbivorous fish species contained lower THg levels than the piscivorous species; this was consistent with similar findings in other fish studies. In general the fish from the Tanzanian reservoirs contained very low mercury concentrations, and differed markedly from fish in hydroelectric reservoirs of similar age in temperate and other regions, which are reported to contain elevated mercury concentrations. The low levels of mercury in the fish correlated with low background concentrations of THg in sediment and flooded soil (mean 2-8 microg/kg dry weight) in the reservoir surroundings. This suggested a relatively clean reservoir environment that has not been significantly impacted by mercury contamination from natural or anthropogenic sources.

Reappraisal of the historic 1959 cat experiment in Minamata by the Chisso Factory.

Autopsy specimens from the historic cat experiment were recently discovered in a storage area at the Kumamoto University School of Medicine. The specimens were from an experiment prompted by physicians in the Chisso Minamata Plant following the announcement made by the Study Group for Minamata disease. On July 14, 1959 the Group announced that the disease was most likely caused by a kind of organic mercury. In order to prove or disprove that industrial waste from the Chisso Factory was the culprit in Minamata disease, a total of ten cats were fed food mixed with industrial waste produced in the acetaldehyde-producing plant. One of the ten cats, No. 717, was subsequently autopsied but the autopsy findings have never been published or recorded in the literature despite their historic significance. The rediscovered specimens were studied pathologically and biochemically, and were analyzed chemically with currently available techniques. Characteristic lesions of methylmercury poisoning were observed in the central nervous system, and the mercury levels in the cerebrum, cerebellum, liver and kidney were found to be markedly elevated in this animal.

Ménière's disease in childhood.

We report 3 rare cases of Ménière's disease in children. In Case 1 and 3, vertigo, hearing loss and tinnitus recovered soon after medical therapy. In Case 2, however, vertigo recurred and the hearing level on the right side markedly deteriorated. The equal-loudness contours on three-dimensional audiogram showed that right-sided aggravated hearing loss fluctuated for 4 years at middle-and low-frequencies despite medication. Finally intratympanic injection of gentamicin sulfate was performed. The patient has had no definitive spell of vertigo after gentamicin therapy. At our department, the incidence of Ménière's disease in pediatric patients with vertigo was 2.9%.

Micron, a microsatellite-targeting transposable element in the rice genome.

We have isolated a new family of mobile elements, Micron, which occur within microsatellites dispersed throughout the rice (Oryza sativa) genome. The first of these segments, Micron 001, was found in a microsatellite consisting of a (TA)n sequence upstream of the rice phytochrome A (phyA) gene. PCR analysis of related rice species suggests that Micron 001 integrated into this microsatellite locus prior to the divergence of the two wild species O. rufipogon and O. barthii from a common ancestor. Micron elements are short (393-bp), possess subterminal inverted repeats and the single strands have the potential to form stable secondary structures via several internal repeats. Aside from the absence of terminal inverted repeats, these characteristics resemble those of MITEs (Miniature Inverted-Repeat Transposable Elements). We estimate that 100-200 copies of Micron-related sequences are present in the rice nuclear genome, while the chloroplast and mitochondrial genomes lack this sequence. Nineteen homologs of Micron 001 exhibited extremely high nucleotide sequence conservation (greater than 90%), suggesting a recent spread of Micron elements within the genus Oryza. Surprisingly, nucleotide sequence alignments showed that all of the Micron elements are flanked on both sides by microsatellite sequence consisting mainly of (TA)n. Twenty-three elements were mapped to seven separate chromosomes. Therefore Micron elements form a family of dispersed, highly conserved repeats. This is the first report of a transposable element that targets microsatellite loci.

Declining Minamata male birth ratio associated with increased male fetal death due to heavy methylmercury pollution.

The purpose of this retrospective study was to examine the effect of methylmercury pollution on the sex ratio of offspring at birth and of fetuses at stillbirth in Minamata City, Japan, in the 1950s when severe and widespread methylmercury pollution was experienced. In 4 of 5 years from 1955 to 1959 when methylmercury pollution was most severe, lower numbers of male offspring at birth were observed in the city population. The offspring sex distributions from 1950 to 1969 by 5-year period were calculated in the overall population of Minamata City, in the most prevalent area, in fishermen (most heavily exposed occupation group) and among Minamata disease patients using data from birth certificates. We also similarly calculated the sex ratio of stillborn fetuses in the city population using Kumamoto Prefecture's vital statistics on still-birth. Decreases in male births were observed in offspring in the overall city population, in fishermen, and in maternal Minamata disease patients in the city in 1955-1959, when the methylmercury pollution was most severe. An increase in the proportion of male stillborn fetuses in the city was observed at the time. It is possible that male fetuses were more susceptible to the pollution than their female counterparts, and this could be a cause for the lower numbers of male offspring at birth.

Cognitive behavioral therapy for chronic fatigue syndrome in a general hospital--feasible and effective.

Cognitive behavior therapy (CBT) has been shown to be effective in recent randomized controlled trials for chronic fatigue syndrome (CFS). We examined the effectiveness of CBT in a general hospital setting in a retrospective questionnaire follow-up study of 94 patients offered CBT by liaison psychiatry services. The questionnaire response rate was 61%. Eighteen percent had returned to normal functioning at follow-up. For the group as a whole, there was a significant improvement in the functional and social impairment and the number of frequently experienced symptoms. Those in work or study at follow-up was 53% (29% pretreatment), and 65% of patients mentioned occupational stress as a contributory factor in their illness. There was a significant reduction in the frequency of attendance at primary care in the year after the end of CBT. We conclude that cognitive behavioral therapy is an acceptable treatment for most patients and can be used in a general hospital outpatient setting by a variety of trained therapists. However, a proportion of patients do not benefit and remain significantly disabled by the condition.

Total and methylmercury levels of a coastal human population and of fish from the Brazilian northeast.

A descriptive exposure survey was conduced at Santa Cruz Channel, Pernambuco, Brazil, to assess the possible risk of mercury contamination to which a coastal human population could be exposed through fish consumption. The area was formerly known to be contaminated due to a chlor-alkali plant installed along one of the tributaries of the channel. The values for total and methylmercury were measured in human hair from inhabitants of Itapissuma (1.9 +/- 1.6 ng THg/mg and 1.2 +/- 1.0 ng MHg/mg--mean values), a coastal fishing village, and fish (Mugil sp.) catch in the area (26.9 +/- 26.1 ng THg/g and 19.6 +/- 16.0 ng MHg/g--mean values). Both human hair and fish muscle presented relatively low values for total and methylmercury concentrations. These were found to be well within the average when compared to other Brazilian coastal environments.

Certification of the methylmercury content in SRM 2977 mussel tissue (organic contaminants and trace elements) and SRM 1566b oyster tissue.

The methylmercury content in two new marine bivalve mollusk tissue Standard Reference Materials (SRMs) has been certified using results of analyses from the National Institute of Standards and Technology (NIST) and two other laboratories. The certified concentrations of methylmercury were established based on the results from four and six different (independent) analytical methods, respectively, for SRM 1566b Oyster Tissue (13.2 +/- 0.7 microg/kg) and SRM 2977 Mussel Tissue (organic contaminants and trace elements) (36.2 +/- 1.7 microg/kg). The certified concentration of methylmercury in SRM 1566b is among the lowest in any certified reference material (CRM).

Improvement of water-soluble cephalosporin derivatives having antibacterial activity against methicillin-resistant Staphylococcus aureus.

We evaluated a series of novel cephem antibiotics, N-alkylpyridinium (alkyl group), N-carboxyethylpyridinium (carboxylic group), N-sulfoethylpyridinium (sulfonic group) and N-alkylquaternary ammonium salts (ammonioethyl group), N-alkyl-aromatic-quaternary ammonium salts and N-alkyl-heterocyclic quaternary ammonium salts (cyclic group) as vinylthio pyridinium derivatives at the C-3 position and hydroxyiminoaminothiazol at the C-7 position, for their activity against methicillin-resistant Staphylococcus aureus (MRSA) and their solubility, by measuring the minimum inhibitory concentrations (MICs) and the dissolving test in phosphate buffer. All tested compounds, except for the alkyl group, showed good solubility (>10%) in 1/15 M phosphate buffer (pH 7.2). The concentrations required to inhibit 80% of the bacterial strains (MIC80s) of the alkyl group, carboxylic group, sulfonic group, ammonioethyl group and cyclic group against MRSA were 1.56, 12.5-25, 6.25, 1.56 and 1.56 microg/ml, respectively. These results indicated that the ammonioethyl and cyclic groups yield the maximum anti-MRSA and anti-Enterococcus faecalis activity, and also good water solubility.