Methanolobus halotolerans sp. nov., isolated from the saline Lake Tus in Siberia.

A halotolerant, psychrotolerant and methylotrophic methanogen, strain SY-01T, was isolated from the saline Lake Tus in Siberia. Cells of strain SY-01T were non-motile, cocci and 0.8-1.0 µm in diameter. The only methanogenic substrate utilized by strain SY-01T was methanol. The temperature range of growth for strain SY-01T was from 4 to 40 °C and the optimal temperature for growth was 30 °C. The pH range of growth was from pH 7.2 to 9.0, with optimal growth at pH 8.0. The NaCl range of growth was 0-1.55 M with optimal growth at 0.51 M NaCl. The G+C content of the genome of strain SY-01T was 43.6 mol % as determined by genome sequencing. Phylogenetic analysis revealed that strain SY-01T was most closely related to Methanolobus zinderi SD1T (97.3 % 16S rRNA gene sequence similarity), and had 95.5-97.2 % similarities to other Methanolobus species with valid names. Genome relatedness between strain SY-01T and DSM 21339T was computed using average nucleotide identity and digital DNA-DNAhybridization, which yielded values of 79.7 and 21.7 %, respectively. Based on morphological, phenotypic, phylogenetic and genomic relatedness data presented here, it is evident that strain SY-01T represents a novel species of the genus Methanolobus, and the name Methanolobus halotolerans sp. nov. is proposed. The type strain is SY-01T (=BCRC AR10051T=NBRC 113166 T=DSM 107642T).

Methanolobus psychrotolerans sp. nov., a psychrotolerant methanoarchaeon isolated from a saline meromictic lake in Siberia.

A psychrotolerant, methylotrophic methanogen, strain YSF-03T, was isolated from the saline meromictic Lake Shira in Siberia. Cells of strain YSF-03T were non-motile, irregular cocci and 0.8-1.2 µm in diameter. The methanogenic substrates utilized by strain YSF-03T were methanol and trimethylamine. The temperature range of growth for strain YSF-03T was from 0 to 37 °C. The optimum growth conditions were 30-37 °C, pH 7.0-7.4 and 0.17 M NaCl. The G+C content of the genome of strain YSF-03T was 41.3 mol%. Phylogenetic analysis revealed that strain YSF-03T was most closely related to Methanolobus profundi MobMT (98.15 % similarity in 16S rRNA gene sequence). Genome relatedness between strain YSF-03T and MobMT was computed using the Genome-to-Genome Distance Calculator and average nucleotide identity, which gave values of 23.5 and 79.3 %, respectively. Based on the morphological, phenotypic, phylogenetic and genomic relatedness data presented here, it is evident that strain YSF-03T represents a novel species of the genus Methanolobus, for which the name Methanolobus psychrotolerans sp. nov. is proposed. The type strain is YSF-03T (=BCRC AR10049T=DSM 104044T=NBRC 112514T).

Effect of mouth-opening levels on sound field gain in the ear canal.

The human external auditory canal can become deformed when the mandible moves, and this changes the sound field in the external auditory canal. This study measured the sound field gain in the external auditory canal while varying mouth-opening in three levels. The mandible was fixed at the 1/3, the 2/3, and the maximal mouth-opening levels. Seven 65-dB tones of 200, 500, 1000, 2000, 4000, 6000, and 8000 Hz, which are the sound pressure level and frequency range when people are talking at a normal level, were adopted as the sound stimulus to measure sound field gains at 5, 10, 15, and 20 mm to the interior of the external auditory canal. The results show that, with the exception of the 1.25 dB decrease from 12.96 to 11.71 dB at a depth of 5 mm with a stimulus at 8000 Hz, the differences in the sound field gain at the other depths and stimulus frequencies were within 1 dB and were not statistically significant. These results suggest that mouth-opening level has no effect on the measurement of the sound field in the external auditory canal.

Aliidiomarina shirensis sp. nov., a halophilic bacterium isolated from Shira Lake in Khakasia, southern Siberia, and a proposal to transfer Idiomarina maris to the genus Aliidiomarina.

Strain AIS(T), an aerobic halophilic, Gram-reaction-negative, heterotrophic bacterium isolated from the water of Shira Lake in Khakasia, southern Siberia, was characterized using a polyphasic approach. Our analysis of the 16S rRNA gene sequences showed that 'Aliidiomarina haloalkalitolerans', 'Aliidiomarina sanyensis', Idiomarina maris and AIS(T) formed a distinct lineage. The sequence similarities between AIS(T) and the type strains of species of the genera Idiomarina and Aliidiomarina were 91.6-95.1 % and 94.0-96.9 %, respectively. The major isoprenoid quinone of AIS(T) was ubiquinone 8 (Q-8). Predominant cellular fatty acids were iso-C17 : 0, iso-C15 : 0 and summed feature 9. The genomic DNA G+C content was 45.8 mol%. It is concluded that AIS(T) represents a novel species of the genus Aliidiomarina, and the name Aliidiomarina shirensis sp. nov. is herein proposed for it. The type strain is AIS(T) ( = JCM 17761(T) = BCRC 80327(T)). Based on its fatty acid profile and our phylogenetic analysis, we propose that Idiomarina maris be transferred to the genus Aliidiomarina.

Salvaging high-quality genomes of microbial species from a meromictic lake using a hybrid sequencing approach.

Most of Earth's bacteria have yet to be cultivated. The metabolic and functional potentials of these uncultivated microorganisms thus remain mysterious, and the metagenome-assembled genome (MAG) approach is the most robust method for uncovering these potentials. However, MAGs discovered by conventional metagenomic assembly and binning are usually highly fragmented genomes with heterogeneous sequence contamination. In this study, we combined Illumina and Nanopore data to develop a new workflow to reconstruct 233 MAGs-six novel bacterial orders, 20 families, 66 genera, and 154 species-from Lake Shunet, a secluded meromictic lake in Siberia. With our workflow, the average N50 of reconstructed MAGs greatly increased 10-40-fold compared to when the conventional Illumina assembly and binning method were used. More importantly, six complete MAGs were recovered from our datasets. The recovery of 154 novel species MAGs from a rarely explored lake greatly expands the current bacterial genome encyclopedia.

Crusted scabies with scalp involvement in an institutionalized elderly.

Scabies is a common disease and typically described as a skin condition with sparing of face and scalp in adults. However, crusted scabies is not conventional scabies. It can also affect the scalp. Herein, we report an unusual case of crusted scabies with scalp infestation and suggest that for cases with suspicious lesions on scalp, immunocompromised patients or relapse cases, crusted scabies, special age groups, such as infant, young children, and the elderly, topical treatment of the scalp should be included.

Prevalence of adult atopic dermatitis among nursing staff in a Taiwanese medical center: a pilot study on validation of diagnostic questionnaires.

BACKGROUND: Atopic dermatitis (AD) is a chronic, relapsing dermatosis. Previous studies have focused mostly on pediatric patients, and investigations emphasizing adult AD have been limited. OBJECTIVE: We set out to determine the 1-year prevalence and evaluate the validity of the International Study of Asthma and Allergies in Childhood (ISAAC) and United Kingdom Working Party (UKWP) AD questionnaires of adult AD in Taiwan. METHODS: We conducted a cross-sectional study among nursing staff at a university hospital. The 1-year prevalence of AD was assessed by ISAAC and UKWP questionnaires. Subsequently, the dermatologists' diagnosis based on Hanifin and Rajka criteria was used as a reference for validation. RESULTS: The overall response rate was 92.9%, equivalent to 1131 complete questionnaires. Ninety adult patients with AD (8%) were identified by dermatologists' diagnosis whereas ISAAC identified 107 (9.5%); sensitivity and specificity were 36.7% and 92.9%, respectively. UKWP identified 42 (3.7%) patients with AD; sensitivity and specificity were 42.2% and 99.6%, respectively. Using the receiver operating characteristic curve analysis, the UKWP criteria performed significantly better than its ISAAC counterpart. Further analysis indicated that modification of these criteria resulted in significant improvement in their diagnostic efficacy. More specifically, modified ISAAC showed 90.0% and 55.2% sensitivity and specificity, respectively, whereas modified UKWP demonstrated 82.2% and 94.2% sensitivity and specificity, respectively. LIMITATION: Most of the study subjects were female with a high educational background. CONCLUSION: Currently available questionnaire instruments do not perform well in the identification of adult patients with AD. Modification of the original questionnaires may allow for future large-scale epidemiologic studies.

The Mechanism of Onychomadesis (Nail Shedding) and Beau's Lines Following Hand-Foot-Mouth Disease.

BACKGROUND: Nail changes, including onychomadesis (nail shedding) and Beau's line, following hand-foot-mouth disease (HFMD) are a common emergence at the stage of late complications of HFMD. However, the exact mechanism is still unknown. Therefore, we conducted this study to elucidate the mechanism of nail changes following HFMD. METHODS: We collected 11 patients suffering from onychomadesis following HFMD. Nail samples from all of them were collected. Real time reverse transcription polymerase chain reaction (RT-PCR) and sequencing for human enteroviruses (HEV) were performed. Throat swabs for RT-PCR and sequencing for HEV were performed for three cases. RESULTS: RT-PCR demonstrated the presence of Coxackievirus A6 (CVA6) in nail samples from three patients and one with Echovirus. CONCLUSION: In conclusion, we believe that the major cause of onychomadesis following HFMD is that certain novel viruses, mostly CVA6, are virulent and may damage nail matrix. Direct injury caused by cutaneous lesions of HFMD around nail matrix is a minor cause. There are still other virulent HEV which may result in onychomadesis. In addition, the novel strain of CVA6 also causes atypical clinical presentations, such as adult involvement and delayed-onset palmar and plantar desquamation. Physicians should be familiar with atypical presentations caused by novel viruses to avoid misdiagnosis and even inform patients of the possibility of onychomadesis that may take place weeks later to reassure patients.

A single lesion showing features of pigmented eccrine poroma and poroid hidradenoma.

Poroid hidradenoma (PH) is a variant of poroma. This entity was defined by Abenoza and Ackerman in 1990. This neoplasm shows architectural characteristics of hidradenoma (tumor cells confined entirely within the dermis in both solid and cystic components) and cytologic characteristics of poroid neoplasm (poroid and cuticular cells, the latter showing ductal differentiation). We herein document a case of single poroid lesion with the features of both eccrine poroma and PH. The patient was a 55-year-old woman with a pigmented nodular lesion on her upper back for 7 years. The histopathologic features of the lesion were consistent with those of eccrine poroma and PH. Unlike most eccrine poromas, this case was pigmented, clinically and microscopically.

Comprehensive Insights Into Composition, Metabolic Potentials, and Interactions Among Archaeal, Bacterial, and Viral Assemblages in Meromictic Lake Shunet in Siberia.

Microorganisms are critical to maintaining stratified biogeochemical characteristics in meromictic lakes; however, their community composition and potential roles in nutrient cycling are not thoroughly described. Both metagenomics and metaviromics were used to determine the composition and capacity of archaea, bacteria, and viruses along the water column in the landlocked meromictic Lake Shunet in Siberia. Deep sequencing of 265 Gb and high-quality assembly revealed a near-complete genome corresponding to Nonlabens sp. sh3vir. in a viral sample and 38 bacterial bins (0.2-5.3 Mb each). The mixolimnion (3.0 m) had the most diverse archaeal, bacterial, and viral communities, followed by the monimolimnion (5.5 m) and chemocline (5.0 m). The bacterial and archaeal communities were dominated by Thiocapsa and Methanococcoides, respectively, whereas the viral community was dominated by Siphoviridae. The archaeal and bacterial assemblages and the associated energy metabolism were significantly related to the various depths, in accordance with the stratification of physicochemical parameters. Reconstructed elemental nutrient cycles of the three layers were interconnected, including co-occurrence of denitrification and nitrogen fixation in each layer and involved unique processes due to specific biogeochemical properties at the respective depths. According to the gene annotation, several pre-dominant yet unknown and uncultured bacteria also play potentially important roles in nutrient cycling. Reciprocal BLAST analysis revealed that the viruses were specific to the host archaea and bacteria in the mixolimnion. This study provides insights into the bacterial, archaeal, and viral assemblages and the corresponding capacity potentials in Lake Shunet, one of the three meromictic lakes in central Asia. Lake Shunet was determined to harbor specific and diverse viral, bacterial, and archaeal communities that intimately interacted, revealing patterns shaped by indigenous physicochemical parameters.

Isolation and characterization of marine luminous bacteria from shallow coastal waters of Taiwan.

BACKGROUND AND PURPOSE: Marine luminous bacteria were isolated and identified from samples in shallow coastal waters of Taiwan during the relatively warm seasons. METHODS: Identification of the luminous isolates was performed based on differences of phenotypic and genotypic characteristics together with data from phylogenetic analysis. RESULTS: Twenty seven strains of marine luminous bacteria were isolated. They were divided into five types based on differences of phenotypic characteristics. However, they could be clustered into only two genotypes according to the analysis of restriction patterns of polymerase chain reaction-amplified 16S rRNA genes digested with various restriction enzymes. The characterization data together with the 16S rRNA gene-based phylogenetic analysis revealed that the isolates included in phenotype I (seven isolates) could be Photobacterium leiognathi, and those included in phenotypes II-V (twenty isolates) might be classified as Vibrio harveyi. However, phylogeny based on gyrB sequences indicated that phenotypes II-V could be classified into two species, V. harveyi and Vibrio campbellii. CONCLUSION: Culturable luminous bacteria in the shallow coastal waters of Taiwan during the sampling period are dominated by V. harveyi/campbellii and P. leiognathi, and the former species appeared to be more prevalent and numerous than the latter species in general.

Alopecia syphilitica.

Alopecia syphilitica is a less common manifestation of secondary syphilis. It could present with other mucocutaneous symptoms of secondary syphilis or rarely present as the only symptom of secondary syphilis, the so-called "essential syphilitic alopecia." Herein, we present a case of essential syphilitic alopecia to remind physicians, especially for sexually active patients.

CD30 is involved in inhibition of T-cell proliferation by Hodgkin's Reed-Sternberg cells.

CD30 is expressed on Hodgkin's Reed-Sternberg (H-RS) cells, the tumor cells in Hodgkin's disease. Increased levels of serum CD30 are observed in Hodgkin's disease patients and are a good marker for predicting a poor prognosis and a poor response to therapy. In this study, we addressed the effect of CD30 on T cells. We showed that CD30, either as a membranous protein on H-RS cells and Chinese hamster ovary cells or as a plate-bound chimeric protein, inhibited T-cell proliferation. Anti-CD3-stimulated T cells in the presence of CD30 failed to increase tritium uptake and failed to express CD25 and CD26 and to produce interleukin 2. The inhibition of T-cell proliferation was, however, reversed with addition of exogenous interleukin 2 or pretreatment of H-RS cells with anti-CD30. Inability of T cells to express CD25 and CD26 in cocultures with H-RS cells or a plate-bound CD30 chimeric protein is in accordance with the results of immunohistochemistry on disease-involved tissues. We conclude that H-RS cells are able to inhibit the proliferation and activation of T cells through CD30-related interaction. The outcome of CD30-related interaction is an ineffective antitumor immunity, which is clearly in favor of the growth and survival of the tumor cells.

Bacterial Communities of Three Saline Meromictic Lakes in Central Asia.

Meromictic lakes located in landlocked steppes of central Asia (~2500 km inland) have unique geophysiochemical characteristics compared to other meromictic lakes. To characterize their bacteria and elucidate relationships between those bacteria and surrounding environments, water samples were collected from three saline meromictic lakes (Lakes Shira, Shunet and Oigon) in the border between Siberia and the West Mongolia, near the center of Asia. Based on in-depth tag pyrosequencing, bacterial communities were highly variable and dissimilar among lakes and between oxic and anoxic layers within individual lakes. Proteobacteria, Bacteroidetes, Cyanobacteria, Actinobacteria and Firmicutes were the most abundant phyla, whereas three genera of purple sulfur bacteria (a novel genus, Thiocapsa and Halochromatium) were predominant bacterial components in the anoxic layer of Lake Shira (~20.6% of relative abundance), Lake Shunet (~27.1%) and Lake Oigon (~9.25%), respectively. However, few known green sulfur bacteria were detected. Notably, 3.94% of all sequencing reads were classified into 19 candidate divisions, which was especially high (23.12%) in the anoxic layer of Lake Shunet. Furthermore, several hydro-parameters (temperature, pH, dissolved oxygen, H2S and salinity) were associated (P< 0.05) with variations in dominant bacterial groups. In conclusion, based on highly variable bacterial composition in water layers or lakes, we inferred that the meromictic ecosystem was characterized by high diversity and heterogenous niches.

Transient hypogammaglobulinemia of infancy presenting as Staphylococcus aureus sepsis with deep neck infection.

Transient hypogammaglobulinemia of infancy (THI) is characterized by a prolongation and accentuation of the physiologic hypogammaglobulinemia normally occurring during the first 3 to 6 months of life and recovers spontaneously between 18 and 36 months of age. Infants with THI may remain asymptomatic or develop recurrent sinopulmonary infections, but severe or life-threatening infections are rare. We report a case of THI in a previously healthy 1-year-old girl with Staphylococcus aureus sepsis who subsequently developed deep neck infection confirmed by magnetic resonance imaging. Intravenous oxacillin was administered for 21 days and she recovered completely. Immunologic studies were normal except for decreased immunoglobulin G levels. Under the impression of hypogammaglobulinemia with severe infection she received regular intravenous immunoglobulins (IVIG) replacement therapy every 4 weeks. One year later, the immunoglobulin concentrations had returned to the normal range even though IVIG had been discontinued for 4 months. This case report highlights the possibility of severe infection in THI, a disease which usually has a benign clinical course. As the diagnosis of THI can only be made with certainty in retrospect, long-term follow-up of clinical and immune system status is necessary.

Epidemiologic trends in nosocomial bacteremia in a neonatal intensive care unit.

The primary goal of this study was to analyze the epidemiologic features of nosocomial bloodstream infection (NBSI) in a neonatal intensive care unit over a 7-year period. All neonatal patients with NBSI treated from January 1997 to December 2003 were retrospectively analyzed. 232 NBSI episodes were diagnosed in 208 patients. The average NBSI patient-day rates were 4.69 and 2.59 per 1000 patient-days in 1997-1999 and 2000-2003, respectively. The average NBSI rates were 5.00 and 1.50 per 1000 patient days in neonates <1500 g and > or =1500 g, respectively. The proportion of Gram-positive organisms increased from 24% in 1997-2001 to 41% in 2002-2003, whereas the proportion of Gram-negative isolates decreased from 65% in 1997-2001 to 47% in 2002-2003. The implementation of measures for the prevention of nosocomial infection was associated with the reduction of NBSI rates. Low birth weight was demonstrated to be a significant risk factor for NBSI. The fact that Gram-positive organisms were isolated in increasing frequency may impact on the appropriate selection of empiric antimicrobial therapy for NBSI in the neonatal intensive care unit.

Effects of porous-hydroxyapatite incorporated into glass-ionomer sealants.

The purpose of the present study was to evaluate the mechanical and chemical properties of a novel glass ionomer cement for use as a pit and fissure sealant containing a porous hydroxyapatite, namely, apatite ionomer cement (AIC). Control sealant samples were used Fuji III (GIC-S). The experiment sealant samples (AIC-S) consisted of porous spherical hydroxyapatite (HApS) particles added at 28 wt% to GIC-S powder. The GIC-S and AIC-S samples were evaluated through mechanical strength measurements, scanning electron microscopy observations, energy dispersive X-ray spectroscopy analysis, fluoride ion release tests, and antibacterial tests. The flexural strength of the AIC-S was significantly higher than that of GIC-S for each period, 1 h, 24 h and 1 year. The fluoride release dose for AIC-S was consistently higher than that for GIC-S. In addition, the antibacterial properties of AIC-S were superior to those of GIC-S. The novel AIC-S may be a more suitable sealant material for pits and fissures with intact and/or infected enamel.

Nosocomial bloodstream infection in a neonatal intensive care unit of a medical center: a three-year review.

Bloodstream infections are the most frequent nosocomial infections in neonatal intensive care units. This retrospective study surveyed the epidemiologic characteristics of nosocomial bloodstream infections which occurred in the neonatal intensive care unit from January 1, 1997 to December 31, 1999. The overall infection patient rate was 5.5% in the 3-year period, and the overall infection patient-day rate was 4.4 per 1000 patient-days. Low birth weight was a risk factor for bloodstream infections. The rate of infection for neonates with birth weight below 1000 g ranged from 36.6% to 45.8% (1997: 36.6%; 1998: 45.8% and 1999: 38.9%). The most common pathogens causing nosocomial bloodstream infection were: Staphylococcus aureus (18.5%) (with 92% oxacillin-resistant), Acinectobacter baumannii (16.3%), Klebsiella pneumoniae (11.9%), Escherichia coli (9.6%), and Pseudomonas aeruginosa (8.1%). The mortality due to nosocomial bloodstream infection was highest among gram-negative bacteria, especially with P. aeruginosa (45.5%). Therefore, surveillance of nosocomial bloodstream infection and successful strategies to decrease nosocomial bloodstream infection, such as infection control and optimal antibiotic use, are warranted.

Monotherapy with meropenem versus combination therapy with ceftazidime plus amikacin as empirical therapy for neutropenic fever in children with malignancy.

Fifty-four pediatric cancer patients with a total of 100 febrile neutropenic episodes treated at China Medical College Hospital were randomized to receive meropenem or ceftazidime plus amikacin from January 2001 to April 2002. The characteristics of 76 assessable febrile episodes (39 with meropenem and 37 with ceftazidime plus amikacin) were compared between the 2 groups. The success rate with unmodified therapy was not significantly different between the meropenem group (72%) and the ceftazidime-plus-amikacin group (57%). The incidence of side effects was similar between the 2 groups and these side effects were reversible. Microbiologically documented infection, clinically documented infection, and unexplained fever accounted for 35%, 37%, and 28% of episodes, respectively. The clinical response rates in subgroups of documented infection and unexplained fever did not significantly differ between the 2 treatment groups. Meropenem was significantly more effective than ceftazidime plus amikacin in children at high risks of developing severe infection who had profound neutropenia (absolute neutrophil count [ANC] < 100/mm3), prolonged neutropenia (ANC < 500/mm3 lasting for > 10 days), or clinically deteriorating shock (p=0.045). As an empirical treatment, meropenem seems to be as effective and safe as ceftazidime plus amikacin for febrile episodes in children with cancer and neutropenia. Meropenem is more effective for pediatric cancer patients at the high risk of severe infection.