Histochemical localization of sialic acids and antimicrobial substances in eccrine glands of porcine snout skin.

The distribution of sialic acids and antimicrobial products (lysozyme, IgA, lactoferrin, ß-defensin 2) as well as Rab3D in the eccrine glands of porcine snout skin was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium consisted of two types of secretory cells: dark and clear cells. The dark cells exhibited considerable amounts of sialoglycoconjugates, which included O-acetylated sialic acids, whereas sialic acids in the sequence Siaα2-3Gal1-4GlcNAc were confined to some of the dark cells. All antimicrobial substances and Rab3D were demonstrated to be also mainly present in some of the dark cells. Additionally, in the cytological and cytochemical features, the different characteristics were observed among the dark cells. The results obtained are discussed with regard to the functional significance of the eccrine glands. The secretory products elaborated by this gland type may function as protective agents in order to preserve the skin integrity of the snout region, considering that sialic acids and antimicrobial substances are important in general defense mechanisms.

Antihypertensive effect of a fixed-dose combination of losartan/hydrochlorothiazide in patients with uncontrolled hypertension: a multicenter study.

BACKGROUND: Achieving adequate blood pressure (BP) control often requires more than one antihypertensive agent. The purpose of this study was to determine whether a fixed-dose formulation of losartan (LOS) plus hydrochlorothiazide (HCTZ) (LOS/HCTZ) is effective in achieving a greater BP lowering in patients with uncontrolled hypertension. METHODS: The study was a prospective, multicenter, observational trial exploring the antihypertensive effect of a single tablet of LOS 50 mg/HCTZ 12.5 mg. A total of 228 patients whose BP had previously been treated with more than one antihypertensive agents without having achieved BP goal below 130/80 mmHg enrolled in the study. RESULTS: A significant decrease in systolic and diastolic BP was observed in both clinic and home measurement after switching from the previous treatment to LOS/HCTZ. There was a significant decrease in both B-type natriuretic peptide (BNP) and urinary albumin creatinine (Cr) excretion ratio (ACR), especially in patients with elevated values. In contrast, there was a significant increase in serum Cr concentration in conjunction with a decrease in estimated glomerular filtration rate (eGFR). Overall serum uric acid (UA) concentration increased, whereas in patients with hyperuricemia there was a significant reduction in this value. CONCLUSION: Switching to LOS/HCTZ provides a greater reduction in clinic and home BP in patients with uncontrolled hypertension. This combination therapy may lead to cardio-, reno protection and improve UA metabolism.

Comment on "temperature-dependent localized excitations of doped carriers in superconducting diamond".

A Comment on the Letter by K. Ishizaka et al., Phys. Rev. Lett. 100, 166402 (2008)10.1103/PhysRevLett.100.166402. The authors of the Letter offer a Reply.

Secretory vesicle docking to the plasma membrane: molecular mechanism and functional significance.

In regulated exocytic pathways, secretion occurs only in the presence of appropriate stimuli. Professional secretory cells harbour specific storage organelles that release bioactive substances with both controlled timing and quantity in response to the strength and period of stimulation. Although each secretory organelle is highly differentiated in multicellular organisms, the basic regulatory mechanism is thought to be conserved. In most instances, the secretagogue increases the intracellular Ca(2+) concentration from the resting level of approximately 100 nM to somewhere between approximately 10 and 100 microM. Although Ca(2+) sensors of the final fusion reaction, such as synaptotagmin, have been investigated intensively in synaptic vesicle exocytosis, there are other preceding rate-limiting steps influenced by Ca(2+) and other secretory signals, especially in the exocytosis of secretory granules whose time course is much slower than that of synaptic vesicles. The stable docking of secretory vesicles to the fusion site that is only seen in regulated exocytic pathways may represent one such critical step. Here, we review the molecular mechanism of docking, mainly based on recent findings on insulin granules in pancreatic beta cells, and propose a new concept for its functional significance in regulated exocytosis.

Population research of genetic polymorphism at amino acid position 631 in chicken Mx protein with differential antiviral activity.

A single amino acid substitution between Asn and Ser at position 631 in the chicken Mx protein has been reported to determine resistant and sensitive antiviral activity. In this study, we investigate whether various kinds of chicken breeds and jungle fowls carry the resistant or sensitive Mx allelic gene by using the mismatched PCR-restriction fragment length polymorphism (RFLP) technique. In total, 271 samples from 36 strains of 17 chicken breeds and from 3 kinds of jungle fowls were examined. The rates of the resistant Mx gene and sensitive gene were 59.2% and 40.8%, respectively. Only a Red jungle fowl captured in Laos carried the resistant Mx gene, and the other three Red jungle fowls from Indonesia and Gray and Green jungle fowls all had the sensitive Mx gene. These results were confirmed by the determination of amino acid sequences in the GTPase effector domain of jungle fowls.

Global gene expression analysis in liver of obese diabetic db/db mice treated with metformin.

AIMS/HYPOTHESIS: Metformin is widely used as a hypoglycaemic reagent for type 2 diabetes. While the reduction of hepatic gluconeogenesis is thought to be a key effect, the detailed molecular mechanism of action of metformin remains to be elucidated. To gain insight into this, we performed a global gene expression profiling study. MATERIALS AND METHODS: We performed DNA microarray analysis to study global gene expression in the livers of obese diabetic db/db mice 2 h after a single administration of metformin (400 mg/kg). RESULTS: This analysis identified 14 genes that showed at least a 1.5-fold difference in expression following metformin treatment, including a reduction of glucose-6-phosphatase gene expression. The mRNA levels of glucose-6-phosphatase showed one of the best correlations with blood glucose levels among 12,000 genes. Enzymatic activity of glucose-6-phosphatase was also reduced in metformin-treated liver. Moreover, intensive analysis of the expression profile revealed that metformin effected significant alterations in gene expression across at least ten metabolic pathways, including those involved in glycolysis-gluconeogenesis, fatty acid metabolism and amino acid metabolism. CONCLUSIONS/INTERPRETATION: These results suggest that reduction of glucose-6-phosphatase activity, as well as suppression of mRNA expression levels of this gene, in liver is of prime importance for controlling blood glucose levels in vivo, at least at early time points after metformin treatment. Our results also suggest that metformin not only affects expression of specific genes, but also alters the expression level of multiple genes linked to the metabolic pathways involved in glucose and lipid metabolism in the liver.

Value of surveillance blood culture for early diagnosis of occult bacteremia in patients on corticosteroid therapy following allogeneic hematopoietic stem cell transplantation.

Bloodstream infection (BSI) is a significant complication following allogeneic hematopoietic stem cell transplantation (allo-SCT). Corticosteroids mask inflammatory responses, delaying the initiation of antibiotics. We reviewed medical records of 69 allo-SCT patients who had been on >0.5 mg/kg prednisolone to investigate the efficacy of weekly surveillance blood cultures. A total of 36 patients (52%) had positive cultures, 25 definitive BSI and 11 probable BSI. Pathogens in definitive BSI were Staphylococcus epidermidis (n=7), S. aureus (n=4), Entrococcus faecalis (n=3), Pseudomonas aeruginosa (n=5), Acenitobacter lwoffii (n=4), and others (n=10). The median interval from the initiation of corticosteroids to the first positive cultures was 24 days (range, 1-70). At the first positive cultures, 15 patients with definitive BSI were afebrile. Four of them remained afebrile throughout the period of positive surveillance cultures. Patients with afebrile BSI tended to be older (P=0.063), and had in-dwelling central venous catheters less frequently than febrile patients (P<0.0001). Bloodstream pathogens were directly responsible for death in two patients with afebrile BSI. This study demonstrates that cortisosteroid frequently masks inflammatory reactions in allo-SCT recipients given conrticosteroids, and that surveillance blood culture is only diagnostic clue for 'occult' BSI.

Change in neuronal firing patterns in the process of motor command generation for the ocular following response.

To explore the process of motor command generation for the ocular following response, we recorded the activity of single neurons in the medial superior temporal (MST) area of the cortex, the dorsolateral pontine nucleus (DLPN), and the ventral paraflocculus (VPFL) of the cerebellum of alert monkeys during ocular following elicited by sudden movements of a large-field pattern. Using second-order linear-regression models, we analyzed the quantitative relationships between neuronal firing frequency patterns and eye movements or retinal errors specified by three parameters (position, velocity, and acceleration). We first attempted to reconstruct the temporal waveform of each neuronal response to each visual stimulus and computed the coefficients for each parameter using the least-square error method for each stimulus condition. The temporal firing patterns were generally well reconstructed [coefficient of determination index (CD) > 0.7] from either the retinal error or the associated ocular following response. In the MST and DLPN datasets, however, the fit with the retinal error model was generally better than with the eye-movement model, and the estimated coefficients of acceleration and velocity ranged widely, indicating that temporal patterns in these regions showed considerable diversity. The acceleration component is greater in MST and DLPN than in VPFL, suggesting that an integration occurs in this pathway. When we determined how well the temporal patterns of the neuronal responses of a given cell could be reconstructed for all visual stimuli using a single set of coefficients, good fits were found only for Purkinje cells (P- cells) in the VPFL using the eye-movement model. In these cases, the coefficients of acceleration and velocity for each cell were similar, and the mean ratio of the acceleration and velocity coefficients was close to that of motor neurons. These results indicate that individual MST and DLPN neurons are each encoding some selective aspects of the sensory stimulus (visual motion), whereas the P-cells in VPFL are encoding the complete dynamic command signals for the associated motor response (ocular following). We conclude that the sensory-to-motor transformation for the ocular following response occurs at the P-cells in VPFL.

Serum uric acid and renal prognosis in patients with IgA nephropathy.

BACKGROUND/AIMS: This study was designed to elucidate the clinical significance of serum uric acid (SUA) and the relationship between hyperuricemia and renal prognosis in IgA nephropathy. METHODS: The correlation between SUA and other clinical parameters were examined in 748 IgA nephropathy patients (432 males and 316 females). Among these patients, 226 (144 males and 82 females) who were followed for more than 5 years were examined for the relationship between hyperuricemia and renal prognosis. RESULTS: In IgA nephropathy, SUA correlated negatively with creatinine clearance (Ccr), and positively with urinary protein and tubulointerstitial damage. SUA was higher in patients with hypertension or diffuse proliferative glomerulonephritis. Hyperuricemia was a risk factor for renal prognosis, both in terms of serum creatinine (p = 0.0025) and Ccr (p = 0.0057). In 56 patients with normal Ccr at renal biopsy, the change of Ccr after more than 8 years was -22.3 +/- 20.8% in 13 patients with hyperuricemia, compared with +2.6 +/- 39.4% in 43 patients without hyperuricemia (p = 0.0238). Hyperuricemia was related independently to deterioration of Ccr (p = 0.0461). CONCLUSION: Hyperuricemia in IgA nephropathy is derived from both glomerular and tubulointerstitial damage, and correlated with hypertension. Hyperuricemia is a risk factor for renal prognosis in IgA nephropathy.

In vitro antimicrobial susceptibility testing of bacterial enteropathogens causing traveler's diarrhea in four geographic regions.

The emergence of resistant enteropathogens has been reported worldwide. Few data are available on the contemporary in vitro activities of commonly used antimicrobial agents against enteropathogens causing traveler's diarrhea (TD). The susceptibility patterns of antimicrobial agents currently available or under evaluation against pathogens causing TD in four different areas of the world were evaluated. Pathogens were identified in stool samples from U.S., Canadian, or European adults (18 years of age or older) with TD during 1997, visiting India, Mexico, Jamaica, or Kenya. MICs of 11different antimicrobials were determined against 284 bacterial enteropathogens by the agar dilution method. Ciprofloxacin, levofloxacin, ceftriaxone, and azithromycin were highly active in vitro against the enteropathogens, while traditional antimicrobials such as ampicillin, trimethoprim, and trimethoprim/sulfamethoxazole showed high levels and high frequencies of resistance. Rifaximin, a promising and poorly absorbable drug, had an MIC at which 90% of the strains tested were inhibited of 32 microg/ml, 250 times lower than the concentration of this drug in the stools. Amdinocillin, nalidixic acid, and doxycycline showed moderate activity. Fluoroquinolones are still the drugs of choice for TD in most regions of the world, although our study has a limitation due to the lack of Escherichia coli samples from Kenya and possible bias in selection of the patients for evaluation. Azithromycin and rifaximin should be considered as promising new agents. The widespread in vitro resistance of the traditional antimicrobial agents reported since the 1980s and the new finding of resistance to fluoroquinolones in Southeast Asia are the main reasons for monitoring carefully the antimicrobial susceptibility patterns worldwide and for developing and evaluating new antimicrobial agents for the treatment of TD.

The exact expression of glial fibrillary acidic protein (GFAP) in trigeminal ganglion and dental pulp.

The expression in various cell types of peripheral tissues of glial fibrillary acidic protein (GFAP), first discovered as an intermediate filament specific for astrocytes, remains controversial owing to numerous reports of a wide distribution for GFAP-immunoreactivity in various cells. The present study employed immunohistochemistry to investigate the precise expression of GFAP in the dental pulp and trigeminal ganglion of adult rats and wild-type mice as well as GFAP-knockout mice. The exhibition of GFAP-immunoreactivity in the trigeminal ganglion was further examined by a reverse transcription polymerase chain reaction (RT-PCR) technique, and in situ hybridization histochemistry using a specific cRNA probe prepared by us. The immunoreaction for GFAP was recognizable in the axons, Schwann cells, and the fibroblasts in the dental pulp of rats and wild-type littermate mice. However, mice with null mutations in the GFAP gene remained immunoreactive for GFAP in all these locations. Intense GFAP-immunoreactivity was found in a small number of satellite cells in the trigeminal ganglion in all animals examined in this study. RT-PCR analysis demonstrated bands for the GFAP gene corresponding to the length expected from the primer design in the samples of trigeminal ganglion and dental pulp. In situ hybridization histochemistry also showed intense signals for GFAP mRNA in some satellite cells of the trigeminal ganglion, but never in the neurons. These data suggest that the GFAP-immunoreactive molecules in the pulpal axons and fibroblasts react non-specifically with the polyclonal antibody and are probably a closely related type of intermediate filament.

Identification of variants and dual promoters of murine serine/threonine kinase KKIAMRE.

KKIAMRE is a serine/threonine protein kinase whose transcripts increase in the deep cerebellar nuclei of the rabbit after eyeblink conditioning, a model of associative learning and memory. We here characterized the expression, isoforms, and promoters of murine KKIAMRE gene. The expression of KKIAMRE was detected, by in situ hybridization and immunohistochemistry, in neurons in various brain regions including deep cerebellar nuclei. The gene spans approximately 40 kb and consists of 15 exons. Analysis of cDNA clones revealed multiple variants, having diversity in the putative carboxy-terminal regulatory domain, generated by alternative splicing and intraexonal termination. Furthermore, they had alternative 5' noncoding sequences. Primer extension, RNase protection, and transient expression assays revealed that two alternative promoters linked to distinct noncoding exons direct the expression of KKIAMRE. The gene was mapped on chromosomes 5 and 4 in mouse and human, respectively.

Involvement of glial fibrillary acidic protein (GFAP) expressed in astroglial cells in circadian rhythm under constant lighting conditions in mice.

To clarify the role of glial fibrillary acidic protein (GFAP)-expressed glial cells in the circadian clock, we examined GFAP expression in the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) under various lighting conditions in mice. We demonstrated that GFAP expression did not show daily change in the SCN under a light-dark cycle; however, long-term housing under constant lighting conditions led to dramatic changes in GFAP expression, i.e., a decrease in the SCN and an increase in the IGL. Furthermore, mice that had a targeted deletion in the GFAP gene (GFAP mutant mice) showed longer and more arrhythmic circadian activity rhythms in constant lighting conditions than wild-type mice, while GFAP mutant mice exhibited stable circadian rhythms both in a light-dark cycle and constant darkness, and showed normal entrainment to environmental light stimuli. These results suggest that the GFAP-expressed astroglial cells in the SCN and the IGL may have some role in circadian oscillation under constant lighting conditions.

Pyridoxine-induced photosensitivity and hypophosphatasia.

We describe a case of photosensitivity due to pyridoxine hydrochloride (vitamin B(6)) in a heterozygote of hypophosphatasia. Photopatch tests using pyridoxine hydrochloride and pyridoxal 5'-phosphate, compounds referred to as vitamin B(6), with ultraviolet light A irradiation were positive. Laboratory examination showed low serum alkaline phosphatase. Tissue-nonspecific alkaline phosphatase exon amplification from DNA of the patient's lymphocytes detected deletion 1154-1156 hypophosphatasia mutation, indicating that this patient was diagnosed to be a heterozygote of hypophosphatasia. The seric pyridoxal 5'-phosphate level of this patient with hypophosphatasia was higher than in normals. Furthermore, after oral administration of vitamin B(6) this level increased greatly and long-lastingly, and this might be related to the low level of alkaline phosphatase in this patient. Photosensitivity in this patient may have been caused by abnormal metabolism of vitamin B(6) under the hypophosphatic condition.

In vitro phototoxicity of new quinolones: production of active oxygen species and photosensitized lipid peroxidation.

To elucidate photosensitization potentials of new quinolone antibacterial agents, production of active oxygen species and peroxidation of squalene after ultraviolet A exposure were investigated. Production of singlet oxygen and/or hydrogen peroxide was estimated by bleaching of p-nitroso-N,N-dimethylaniline. Lomefloxacin showed the greatest ability to produce active oxygen species, and this ability was reduced by the addition of the singlet oxygen quencher sodium azide. Ciprofloxacin and fleroxacin also had strong activity. Photosensitized peroxidation of squalene was evaluated by measurement of thiobarbituric acid-reactive substances. Lomefloxacin was the strongest sensitizer, followed by fleroxacin and ciprofloxacin. These results suggest that certain new quinolones are involved in phototoxicity via the mechanism of active oxygen species.

Oesophageal involvement in pemphigus vulgaris.

Oesophageal involvement of pemphigus vulgaris had been considered an exceptional event. However, our endoscopic study found oesophageal lesions in seven of eight (87.5%) patients with pemphigus vulgaris.

Learning induces a CDC2-related protein kinase, KKIAMRE.

To elucidate molecular mechanisms in learning and memory, we analyzed expression of mRNAs in brains of rabbits undergoing eyeblink conditioning. Infusion of the transcription inhibitor actinomycin D into the cerebellar interpositus nucleus reversibly blocked learning but not performance of the conditioned response. Differential display PCR analysis of cerebellar interpositus RNAs from trained and pseudotrained rabbits identified a 207 bp band that was induced with learning. The fragment was used to isolate a cDNA from a lambdagt11 rabbit brain library containing a 1698 bp open reading frame. The deduced amino acid sequence contains the KKIAMRE motif, which is conserved among cell division cycle 2 (cdc2)-related kinases. These results suggest that there is a new category of cdc2-related kinases in the brain whose function may be important in learning and memory.