bluuebunny/crossref_metadata_2025 huggingface dataset:
Does partial surgical tumour removal influence the response to octreotide‐LAR in acromegalic patients previously resistant to the somatostatin analogue?
Authors: Jallad Raquel S. , Musolino Nina R. , Kodaira Sergio , Cescato Valter A. , Bronstein Marcello D.
Published: June 2007

Objective  To compare the intrapatient response to the same dose of slow‐release octreotide (OCT‐LAR) before and after noncurative surgery in acromegalic patients who did not attain disease control after primary treatment with OCT‐LAR.

Design  Prospective clinical study.

Patients  Eleven acromegalic patients (eight men, aged 42·45 ± 11·15 years, 10 macroadenomas) received OCT‐LAR (20 mg, n = 1; 30 mg, n = 10) every 28 days as the primary treatment (1stOCT‐LAR) for 11·3 ± 4·2 months, without IGF‐I normalization. They were subsequently submitted to surgery without cure and were then treated with the same dose of OCT‐LAR for 8·0 ± 6·5 months (2ndOCT‐LAR).

Measurements  GH and IGF‐I serum concentrations were obtained under basal conditions as well as during treatment. Pituitary tumour volume was assessed by magnetic resonance imaging (MRI) of the sella. IGF‐I was also expressed as a percentage of the upper limit of the normal age‐ and sex‐matched range (%ULNR IGF‐I).

Results  After 1stOCT‐LAR, there was a decrease in GH levels (P = 0·003) and %ULNR IGF‐I (P = 0·009) compared to baseline (B), but no IGF‐I normalization. Tumour shrinkage was observed in eight of 10 patients with macroadenomas (median 63·7%, range 24·5–75·5%). After surgery, mean levels of GH and %ULNR IGF‐I were lower than those at baseline (P = 0·0004 and P = 0·003, respectively), but not when compared to values during 1stOCT‐LAR (P = 1·000 and P = 0·957, respectively). MRI confirmed surgical tumour removal (median 64%, range 4·9–96·6%) in eight of the 10 patients. Comparing the 2ndOCT‐LAR results with postsurgical results, there were no significant decrease in %ULNR IGF‐I (P = 0·061) and GH levels (P = 0·414). Nine patients (82%) achieved IGF‐I normalization. The degree of surgical tumour reduction did not correlate with IGF‐I normalization (P = 0·794). When comparing the results between 1stOCT‐LAR and 2ndOCT‐LAR, there was a decrease, albeit not statistically significant, in serum GH levels (P = 0·059) and a significant decrease in %ULNR IGF‐I (P = 0·011).

Conclusions  Using strict criteria (same patient, same drug, same dose) our results strongly suggest that the surgical reduction of tumour mass can improve the outcome of OCT‐LAR treatment in acromegalic patients resistant to primary therapy with SA.
Clinical features of thyroid autoimmunity are associated with thyroiditis on histology and are not predictive of malignancy in 570 patients with indeterminate nodules on cytology who had a thyroidectomy
Authors: Rago T. , Di Coscio G. , Ugolini C. , Scutari M. , Basolo F. , Latrofa F. , Romani R. , Berti P. , Grasso L. , Braverman L. E. , Pinchera A. , Vitti P.
Published: June 2007

Background  The relationship between thyroid autoimmunity and cancer is still uncertain.

Patients   We approached this issue in 570 consecutive patients submitted to thyroidectomy for an indeterminate nodule on cytology. Thyroid autoimmunity was defined as positivity of circulating thyroid autoantibodies (TAb), autoimmune hypo‐ or hyperthyroidism, thyroid hypoechogenicity on ultrasound, and lymphocytic infiltration on histology.

Results   TAb were found in 122/570 (21·4%), hypoechogenicity in 115/570 (20·1%), and lymphocytic infiltration in 117/570 (20·5%) of patients. The three features of thyroid autoimmunity were highly concordant: hypoechogenicity was observed in 71/448 (15·8%) patients with negative TAb and in 44/122 (36%) with positive TAb (P < 0·0001); lymphocytic infiltration was found in 53/448 (11·8%) patients with negative TAb and in 64/122 (52·4%) with positive TAb (P < 0·0001); hypoechogenicity on ultrasound was observed in 73/453 (16·1%) patients without, and in 42/117 (35·9%) with lymphocytic infiltration (P < 0·0001). None of these parameters was associated with malignancy. TAb were found in 32/135 (23·7%) patients with carcinoma and in 90/435 (20·6%) with a benign lesion (P = NS); hypoechogenicity was observed in 26/135 (19·2%) patients with carcinoma and in 89/435 (20·4%) patients with benign lesions (P = NS); lymphocytic infiltration was present in 28/135 (20·7%) patients with carcinoma and in 89/435 (20·4%) with benign lesions (P = NS). The frequency of cancer in 11 patients with clinically overt thyroid autoimmune disease did not differ from that observed in the whole study group.

Conclusion   In this group of patients with indeterminate thyroid nodules at cytology, clinical and pathological criteria of thyroid autoimmunity were strongly concordant and not associated with malignancy.
Rosiglitazone decreases 11β‐hydroxysteroid dehydrogenase type 1 in subcutaneous adipose tissue
Authors: Mai Knut , Andres Janin , Bobbert Thomas , Maser‐Gluth Christiane , Möhlig Matthias , Bähr Volker , Pfeiffer Andreas F. H. , Spranger Joachim , Diederich Sven
Published: June 2007

Objective  The peroxisome proliferator‐activated receptor‐γ (PPARγ) agonist rosiglitazone increases insulin sensitivity, which, in animal models, is comparable to the effect of a reduction in 11β‐hydroxysteroid dehydrogenase type 1 (11β‐HSD1) activity. We therefore investigated whether rosiglitazone‐induced insulin sensitivity is associated with changes in 11β‐HSD1 activity in different tissues.

Methods  An oral glucose tolerance test (OGTT) and a euglycaemic hyperinsulinaemic clamp were performed in seven male volunteers [age 59·3 ± 3·0 years, body mass index (BMI) 29·3 ± 4·1 kg/m2] with impaired glucose tolerance before and after 8 weeks of rosiglitazone treatment. To assess hepatic 11β‐HSD1 activity, serum cortisol levels were measured after oral administration of cortisone acetate. 11β‐HSD1 activity and mRNA expression were assessed in abdominal subcutaneous fat biopsies. Total‐body 11β‐HSD activities were estimated by calculating the urinary ratios of glucocorticoid metabolites.

Results  As expected, rosiglitazone improved insulin resistance and postprandial hyperglycaemia. In parallel, 11β‐HSD1 mRNA expression [100 ± 0% (reference) vs. 68·5 ± 9·3%, P < 0·01] and activity [0·18 ± 0·02 vs. 0·13 ± 0·02 pmol/min/mg, P < 0·05] decreased in abdominal subcutaneous fat, while an increase in hepatic 11β‐HSD1 activity was detected [the area under the curve (AUC) for the cortisol/cortisone ratio was 1319 ± 76 vs. 955 ± 59; P < 0·05]. No changes in BMI, waist‐to‐hip ratio (WHR) and whole‐body 11β‐HSD1 activity were found.

Conclusions  Part of the beneficial effects of rosiglitazone may be mediated by a reduction in the 11β‐HSD1 mRNA expression and activity in subcutaneous abdominal fat.
Autoimmune thyroid disease and chronic urticaria
Authors: Monge Cecilia , DeMarco Paul , Burman Kenneth D. , Wartofsky Leonard
Published: June 2007

We report six cases of autoimmune thyroid disease associated with chronic urticaria and briefly review the literature, including the histopathological nature of such lesions, and their aetiology and pathogenesis. In view of the prevalence of thyroid disease in patients with chronic urticaria, screening measurements of thyrotropin and anti‐thyroperoxidase antibodies are recommended, although negative antibodies do not exclude a relationship between urticaria and thyroid autoimmunity. After failure of conventional therapy for urticaria, patients who are apparently clinically euthyroid may be considered for a trial with levothyroxine. Improvement of urticaria was seen with levothyroxine treatment in three of four patients with only marginal abnormalities in thyroid function.
Translabyrinthine surgery for disabling vertigo in vestibular schwannoma patients
Authors: Godefroy W.P. , Hastan D. , Van Der Mey A.G.L.
Published: June 2007

Objective:  To determine the impact of translabyrinthine surgery on the quality of life in vestibular schwannoma patients with rotatory vertigo.

Study design:  Prospective study in 18 vestibular schwannoma patients.

Setting:  The study was conducted in a multispecialty tertiary care clinic.

Participants:  All 18 patients had a unilateral intracanalicular vestibular schwannoma, without serviceable hearing in the affected ear and severely handicapped by attacks of rotatory vertigo and constant dizziness. Despite an initial conservative treatment, extensive vestibular rehabilitation exercises, translabyrinthine surgery was performed because of the disabling character of the vertigo, which considerably continued to affect the patients’ quality of life.

Main outcome measures:  Preoperative and postoperative quality of life using the Short Form 36 Health Survey (Short Form‐36) scores and Dizziness Handicap Inventory (DHI) scores.

Results:  A total of 17 patients (94%) completed the questionnaire preoperatively and 3 and 12 months postoperatively. All Short Form‐36 scales of the studied patients scored significantly lower when compared with the healthy Dutch control sample (P < 0.05). There was a significant improvement of DHI total scores and Short Form‐36 scales on physical and social functioning, role‐physical functioning, role‐emotional functioning, mental health and general health at 12 months after surgery when compared with preoperative scores (P < 0.05).

Conclusions:  Vestibular schwannoma patients with disabling vertigo, experience significant reduced quality of life when compared with a healthy Dutch population. Translabyrinthine tumour removal significantly improved the patients’ quality of life. Surgical treatment should be considered in patients with small‐ or medium‐sized tumours and persisting disabling vertigo resulting in a poor quality of life.
Antimicrobial prophylaxis in otorhinolaryngology/head and neck surgery
Authors: Fennessy B.G. , Harney M. , O'Sullivan M.J. , Timon C.
Published: June 2007

Keypoints

• Prophylactic antimicrobial therapy is defined as the administration of an antimicrobial agent prior to contamination of previously sterile tissues or fluids, in an attempt to reduce the microbial burden of intraoperative contamination. Prophylactic antimicrobial therapy should cover the anticipated floral contamination, with therapeutic levels from incision to closure.

• There is level I evidence to support the use of prophylaxis in clean‐contaminated head and neck procedures and tonsillectomy, while level II evidence fails to support the use of prophylaxis in clean head and neck procedures.

• The aim of this study was to evaluate the use, timing and appropriateness of antimicrobial prophylaxis perioperatively, in otorhinolaryngological/head and neck procedures.

• A total of 34/51 (66%) patients were administered antimicrobial agents prophylactically. Six of 19 patients (42%) who ought to have received prophylaxis did not, while six of 13 (46%) of those who did not require it received it. Administration was unsuitably timed in 14 of 34 (41%) operations.

• This study demonstrates unnecessary administration of antimicrobial agents perioperatively, subclinical intraoperative antimicrobial levels for prophylaxis and inconsistent documentation regarding prophylaxis in otorhinolaryngological/head and neck procedures in a general ENT unit.
Systemic high blood pressure and inner ear dysfunction: a preliminary study
Authors: Esparza C.M. , Jáuregui‐Renaud K. , Morelos C.M.C. , Muhl G.E.A. , Mendez M.N. , Carillo N.S. , Bello N.S. , Cardenas M.
Published: June 2007

Objective:  To assess the association between inner ear dysfunction and retinal vascular changes related to systemic arterial hypertension.

Design:  A comparative, cross‐sectional and observational study.

Setting:  Primary care.

Main outcomes measures:  Hearing and vestibular symptoms evaluated by a standardized questionnaire; cochlear function evaluated by audiometry and distortion product otoacoustic emissions; vestibular function evaluated by oculomotor and bithermal caloric tests and vascular retinal compromise evaluated by ophthalmoscopy (according to the modified Scheie classification).

Results:  Forty‐two subjects participated in the study, 21 with and 21 without arterial hypertension, age and sex matched; with no history of diabetes mellitus and with normal glucose levels and normal blood lipids. Although patients with hypertension reported vertigo more frequently than control subjects, conventional oculomotor and bithermal caloric tests showed no difference between the two groups. Patients with hypertension showed deterioration of hearing thresholds at 8 kHz and, compared with normotensive subjects, a higher frequency of abnormal otoacoustic emissions (P = 0.01). According to Scheie classification, 43% (95% CI: 33–53%) of the patients showed second degree retinal vascular compromise and 24% (95% CI: 15–33%) of them showed first degree compromise. The degree of the vascular retinal compromise was significantly correlated with the hearing thresholds at 8 kHz (Spearman's correlation coefficient 0.45, P = 0.002) and it was also consistent with the absence of otoacoustic emissions at frequencies between 4 and 8 kHz.

Conclusion:  The results of this preliminary study suggest that patients with systemic arterial hypertension may have cochlear dysfunction associated with the vascular disease because of hypertension, which could be silent and without clear evidence of vestibular dysfunction.
Turbidity‐mediated interactions between invasive filter‐feeding mussels and native bioturbating mayflies
Authors: MARTIN OSTERLING E. , BERGMAN EVA , GREENBERG LARRY A. , BALDWIN BRAD S. , MILLS EDWARD L.
Published: June 2007

1. Invasive dreissenid mussels are known to cause large ecosystem changes because of their high filter‐feeding capacity, while native bioturbators may interfere with the mussels filter feeding. In this experiment, we investigated indirect environmental interactions between invasive filter‐feeding dreissenid mussels (zebra and quagga mussels) and native recolonizing bioturbating hexagenid mayflies (Hexagenia) at two mussel densities and two Hexagenia densities in a 2‐month long laboratory experiment.

2. Mean turbidity increased with increasing density of Hexagenia and decreased with increasing density of mussels. Turbidity showed the fastest decline at the highest mussel density, and no decline or a lower rate of decline at the low mussel density, dependent on Hexagenia density.

3. Mussel growth decreased with increasing Hexagenia density at low but not at high mussel density. Moreover, growth of mussels decreased as a function of increased mean turbidity at low mussel density but not at high mussel density. Filtering activity at the highest mussel density increased after introduction of food at the lower two densities of Hexagenia, but was constantly high at the highest Hexagenia density.

4. There was no difference in emergence of Hexagenia among the treatments, but mortality of Hexagenia was higher in the presence of mussels than in their absence.

5. Our results indicate that interactions between dreissenids and hexagenids are mediated through the sediment, and depend on density of both dreissenids and hexagenids. As the natural densities of these animals vary considerably within lakes, their growth and survival because of indirect environmental interactions is expected to vary spatially.
Winter diatom blooms in a regulated river in South Korea: explanations based on evolutionary computation
Authors: KIM DONG‐KYUN , JEONG KWANG‐SEUK , WHIGHAM PETER A. , JOO GEA‐JAE
Published: June 2007

1. An ecological model was developed using genetic programming (GP) to predict the time‐series dynamics of the diatom, Stephanodiscus hantzschii for the lower Nakdong River, South Korea. Eight years of weekly data showed the river to be hypertrophic (chl. a, 45.1 ± 4.19 μg L−1, mean ± SE, n = 427), and S. hantzschii annually formed blooms during the winter to spring flow period (late November to March).

2. A simple non‐linear equation was created to produce a 3‐day sequential forecast of the species biovolume, by means of time series optimization genetic programming (TSOGP). Training data were used in conjunction with a GP algorithm utilizing 7 years of limnological variables (1995–2001). The model was validated by comparing its output with measurements for a specific year with severe blooms (1994). The model accurately predicted timing of the blooms although it slightly underestimated biovolume (training r2 = 0.70, test r2 = 0.78). The model consisted of the following variables: dam discharge and storage, water temperature, Secchi transparency, dissolved oxygen (DO), pH, evaporation and silica concentration.

3. The application of a five‐way cross‐validation test suggested that GP was capable of developing models whose input variables were similar, although the data are randomly used for training. The similarity of input variable selection was approximately 51% between the best model and the top 20 candidate models out of 150 in total (based on both Root Mean Squared Error and the determination coefficients for the test data).

4. Genetic programming was able to determine the ecological importance of different environmental variables affecting the diatoms. A series of sensitivity analyses showed that water temperature was the most sensitive parameter. In addition, the optimal equation was sensitive to DO, Secchi transparency, dam discharge and silica concentration. The analyses thus identified likely causes of the proliferation of diatoms in ‘river‐reservoir hybrids’ (i.e. rivers which have the characteristics of a reservoir during the dry season). This result provides specific information about the bloom of S. hantzschii in river systems, as well as the applicability of inductive methods, such as evolutionary computation to river‐reservoir hybrid systems.
Ovol2/Movo, a homologue of Drosophila ovo, is required for angiogenesis, heart formation and placental development in mice
Authors: Unezaki Sawako , Horai Reiko , Sudo Katsuko , Iwakura Yoichiro , Ito Seiji
Published: June 2007

The zinc‐finger transcription factor Ovol2 (Movo, Movo2) is a mouse homologue of Drosophila ovo, which is essential for the survival and differentiation of female germ line cells. To elucidate OVOL2 function in mammals, we generated Ovol2‐deficient mice by gene targeting. The Ovol2 mutants died at embryonic days 9.5–10.5 (E9.5–E10.5), as a result of defects in extraembryonic and embryonic vascularization, and in heart formation. Although the Ovol2 expression was weak, severe defects were detected in extraembryonic and embryonic vascularization, and in heart formation at E8.5–E9.5. In Ovol2−/− placentas, allantoic blood vessel expansion and development of the labyrinthine layer were impaired at E10.5. In an endothelial cell line, siRNAs for Ovol2 reduced the expression of Ovol2 and inhibited the capillary‐like network formation on Matrigel in vitro. These results demonstrate that Ovol2 may play a critical role in vascular angiogenesis during early embryogenesis.
Anchoring of the 26S proteasome to the organellar membrane by FKBP38
Authors: Nakagawa Tadashi , Shirane Michiko , Iemura Shun‐ichiro , Natsume Tohru , Nakayama Keiichi I.
Published: June 2007

FK506‐binding protein 38 (FKBP38) is a member of the immunophilin family that resides in the mitochondrial outer membrane and the endoplasmic reticulum (ER) membrane. To investigate the physiological function of FKBP38, we performed a comprehensive search for proteins with which it interacts in human cells by liquid chromatographic and mass spectrometric analysis of FKBP38 immunoprecipitates. Almost all subunits of the 26S proteasome were thus found to interact with FKBP38. In vivo co‐immunoprecipitation analyses confirmed that FKBP38 indeed associates with the 26S proteasome via its three tandem tetratricopeptide repeats (TPRs). Binding assays in vitro also revealed that FKBP38 directly interacts with the S4 subunit of the 19S proteasome. Immunofluorescence analysis demonstrated that the subcellular distributions of FKBP38 and the 26S proteasome partially overlapped at mitochondria. Both the abundance and activity of the proteasome in a membrane fraction were markedly reduced for mouse embryonic fibroblasts prepared from Fkbp38−/– mice compared with those prepared from wild‐type mice. These results suggest that FKBP38 functions to anchor the 26S proteasome at the organellar membrane.
Impairment of the ubiquitin‐proteasome system by cellular FLIP
Authors: Ishioka Toshiyasu , Katayama Ryohei , Kikuchi Ryo , Nishimoto Michie , Takada Shinji , Takada Ritsuko , Matsuzawa Shu‐ichi , Reed John C. , Tsuruo Takashi , Naito Mikihiko
Published: June 2007

Cellular FLIP (cFLIP) is a homologue of caspase‐8 without protease activity that inhibits the apoptosis signaling initiated by death receptor ligation. We previously reported that a long form of cFLIP (cFLIP‐L) inhibits ubiquitylation of β‐catenin and enhances Wnt signaling. Here we show that cFLIP‐L impairs the function of the ubiquitin‐proteasome system (UPS), and increases the accumulation of various short‐lived proteins, such as GFP conjugated with destabilization sequence, β‐catenin and HIF1α, that are subjected to rapid ubiquitylation and degradation by proteasomes. Accordingly, β‐catenin‐ and HIF1α‐mediated gene expressions are induced in the cFLIP‐L‐expressing cells. Exogenously expressed cFLIP‐L accumulates in aggregates at the peri‐nuclear region in the cells, and the cFLIP‐L aggregates are refractory to solubilization. Like exogenously expressed cFLIP‐L, the endogenous cFLIP in A549 lung cancer cells displays particulate distribution in the cells and more than 60% of cFLIP‐L is refractory to solubilization. Down‐regulation of cFLIP in A549 cells by RNA‐mediated interference reduced β‐catenin‐ and HIF1α‐mediated gene expression. These results suggest that cFLIP‐L is prone to aggregate and impairs UPS function, which could be involved in the pathological function of cFLIP‐L expressed in certain cancer cells.
RBP2 is an MRG15 complex component and down‐regulates intragenic histone H3 lysine 4 methylation
Authors: Hayakawa Tomohiro , Ohtani Yasuko , Hayakawa Noriyo , Shinmyozu Kaori , Saito Motoki , Ishikawa Fuyuki , Nakayama Jun‐ichi
Published: June 2007

MRG15 is a conserved chromodomain protein that associates with histone deacetylases (HDACs) and Tip60‐containing histone acetyltransferase (HAT) complexes. Here we further characterize MRG15‐containing complexes and show a functional link between MRG15 and histone H3K4 demethylase activity in mammalian cells. MRG15 was predominantly localized to discrete nuclear subdomains enriched for Ser2‐phosphorylated RNA polymerase II, suggesting it is involved specifically with active transcription. Protein analysis of the MRG15‐containing complexes led to the identification of RBP2, a JmjC domain‐containing protein. Remarkably, over‐expression of RBP2 greatly reduced the H3K4 methylation in culture human cells in vivo, and recombinant RBP2 efficiently removed H3K4 methylation of histone tails in vitro. Knockdown of RBP2 resulted in increased H3K4 methylation levels within transcribed regions of active genes. Our findings demonstrate that RBP2 associated with MRG15 complex to maintain reduced H3K4 methylation at transcribed regions, which may ensure the transcriptional elongation state.
Interactions of human Cdc45 with the Mcm2–7 complex, the GINS complex, and DNA polymerases δ and ɛ during S phase
Authors: Bauerschmidt Christina , Pollok Sibyll , Kremmer Elisabeth , Nasheuer Heinz‐Peter , Grosse Frank
Published: June 2007

Cdc45 is an essential cellular protein that functions in both the initiation and elongation of DNA replication. Here, we analyzed the localization of human Cdc45 and its interactions with other proteins during the cell cycle. Human Cdc45 showed a diffuse distribution in G1 phase, a spot‐like pattern in S and G2, and again a diffuse distribution in M phase of the cell cycle. The co‐localization of Cdc45 with active replication sites during S phase suggested that the human Cdc45 protein was part of the elongation complex. This view was corroborated by findings that Cdc45 interacted with the elongating DNA polymerases δ and ɛ, with Psf2, which is a component of the GINS complex as well as with Mcm5 and 7, subunits of the putative replicative DNA helicase complex. Hence, Cdc45 may play an important role in elongation of DNA replication by bridging the processive DNA polymerases δ and ɛ with the replicative helicase in the elongating machinery.
T‐cadherin enhances cell–matrix adhesiveness by regulating β1 integrin trafficking in cutaneous squamous carcinoma cells
Authors: Mukoyama Yohei , Utani Atsushi , Matsui Seiya , Zhou Shuxia , Miyachi Yoshiki , Matsuyoshi Norihisa
Published: June 2007

T‐cadherin is a glycosyl‐phosphatidylinositol (GPI) anchored cadherin molecule. We previously reported that T‐cadherin is normally expressed on the basal keratinocytes of the epidermis and is down‐regulated in cutaneous squamous cell carcinoma (SCC). We found that expression of T‐cadherin in cutaneous squamous carcinoma cells regulated level of surface β1 integrin, which functioned as extracellular matrix (ECM) receptor. Involvement of T‐cadherin in β1 integrin trafficking was studied using three different stable cell lines with cytomegalovirus (CMV)‐driven over‐expression, tetracycline (Tet)‐inducible expression and RNAi‐mediated suppressed expression of T‐cadherin. Pulse–chase analysis using a cholesterol‐depleting reagent and a tyrosine kinase inhibitor showed that β1 integrin mainly internalized via caveolae. Over‐expression of T‐cadherin suppressed the internalization of both β1 integrin and cholera toxin (CTX), a marker of caveolae‐mediated endocytosis. By Western blot analysis of tyrosine‐kinase target molecules, we demonstrated a reduced level of EGF receptor (EGFR)‐phosphorylation in T‐cadherin over‐expressing cells. In addition, studies using EGF and EGFR specific inhibitors revealed that EGFR activation stimulated β1 integrin internalization. Taking these results together, T‐cadherin may modulate cell–matrix adhesion in basal keratinocytes as well as invasive potency in SCC by regulating surface level of β1 integrin.
A qualitative study of information technology adoption: how ten organizations adopted Web‐based training
Authors: Chan Simon C H , Ngai Eric W T
Published: June 2007

Abstract.  Web‐based training (WBT) has become prevalent in business organizations. This study used evidence from 10 organizations in Hong Kong to identify the significant factors that influenced their decision to adopt WBT. A qualitative field study was used. This study concluded the following three key factors significantly affect the adoption of WBT in Hong Kong: (1) the perceived benefits/costs of WBT, (2) organizational readiness, and (3) external pressures. The results and implications are discussed.
Effects of a self‐management arthritis programme with an added exercise component for osteoarthritic knee: randomized controlled trial
Authors: Yip Y. B. , Sit Janet W. H. , Fung Karin K. Y. , Wong Doris Y. S. , Chong Samantha Y. C. , Chung L. H. , Ng T. P.
Published: June 2007

Title. Effects of a self‐management arthritis programme with an added exercise component for osteoarthritic knee: randomized controlled trial.

Aim.  This paper is a report of a study to assess the effect of an adapted arthritis self‐management programme with an added focus on exercise practice among osteoarthritic knee sufferers.

Background.  Osteoarthritis of the knee is a major source of loss of function in older people. Previous studies have found self‐management programmes to be effective in increasing arthritis self‐efficacy and in mastery of self‐management practice.

Method.  A randomized control trial was carried out from December 2002 to May 2003 and 120 participants (65·9%, including 67 in intervention group and 53 in control group) completed the 16‐week postintervention assessments. Outcome measures included arthritis self‐efficacy, use of self‐management techniques, pain intensity and daily activity.

Findings.  At 16 weeks, there was a ‘statistically’ significant improvement in the arthritis self‐efficacy level (P ≤ 0·001), in most of the self‐management skills, i.e. use of cold and hot compresses, in two of three joint protective practices (P ≤ 0·001; P = 0·01), an increase in the duration of light exercise practice (P ≤ 0·001), reduction of current arthritis pain (P ≤ 0·001) and in the ability to perform daily activities (P ≤ 0·001) among the intervention group but not for the control group (P‐range from 0·04 to 0·95). One joint protective practice showed a statistically significant increase in both groups (P ≤ 0·001).

Conclusion.  Our findings add to evidence showing short‐term beneficial effects of self‐efficacy theory in education programmes. Self‐efficacy theory has great potential for empowering sufferers of chronic conditions to live with their illness.
Factors associated with taste dissatisfaction in the elderly
Authors: YOSHINAKA M. , YOSHINAKA M. F. , IKEBE K. , SHIMANUKI Y. , NOKUBI T.
Published: June 2007

summary  The purpose of this study was to investigate taste sensation in the elderly, and to determine relationships between subjective dissatisfaction with taste ability and factors such as age, gender and oral status among independently living elderly individuals. Participants were older adults (mean age, 66·0 ± 4·2 years; 321 men and 319 women) voluntarily attending a Senior Citizen Educational Program supported by local government in 2003 and 2004. The questionnaire included self‐assessed items on general health, dry mouth, chewing satisfaction and taste satisfaction. Respondents underwent investigation of salivary flow rate, dental status and gustatory testing using the filter‐paper disc method for sweet, salty, sour and bitter. Chi‐squared tests showed that the factors associated with dissatisfaction with taste ability were older age, dissatisfaction with chewing, dry mouth during eating and wearing dentures covering the entire hard palate. The sensation for each taste was not significantly related to taste satisfaction by chi‐squared test. Multiple logistic regression analysis showed that dry mouth during eating, dentures covering the entire hard palate, dissatisfaction with chewing and discriminatory threshold for the sour taste were associated with dissatisfaction with taste ability. We found a significant association between subjective taste dissatisfaction and certain oral factors; hence, when patients complain about diminished taste, dentists must assess oral status as well as taste sensation.
Electromyographic activity of masticatory, neck and trunk muscles of subjects with different skeletal facial morphology – a cross‐sectional evaluation
Authors: TECCO S. , CAPUTI S. , FESTA F.
Published: June 2007

summary  The electromyographic pattern activity of masticatory, neck and trunk muscles was assessed using surface electromyography (sEMG) in 60 Caucasian adult females (20 subjects in skeletal class I, 20 subjects in skeletal class II and 20 subjects in skeletal class III), classified on the base of their skeletal class (ANB angle), corrected on the base of maxillary and mandibular rotations. The sEMG activity was recorded at mandibular rest position and during maximal voluntary clenching. At mandibular rest position, the sEMG activities of masseter and anterior temporal muscles were significantly higher in class III subjects than in class I and class II subjects, that showed no significant difference between them. Then, the sEMG activities of posterior cervicals and upper trapezius were significantly higher in skeletal class III subjects than in the other two groups. During maximal voluntary clenching, no significant difference was observed in the sEMG activity of masticatory muscles among the three considered groups. However, the sEMG activities of posterior cervicals and upper trapezius were significantly higher in skeletal class III subjects than in the other two groups, which showed no significant difference between them. In conclusion, the skeletal class seems to affect the sEMG pattern activity of masticatory, neck and trunk muscles.
Development of a novel sticky trap for container‐breeding mosquitoes and evaluation of its sampling properties to monitor urban populations of Aedes albopictus
Authors: FACCHINELLI L. , VALERIO L. , POMBI M. , REITER P. , COSTANTINI C. , DELLA TORRE A.
Published: June 2007

Abstract Collection methods currently used for large‐scale sampling of adult Stegomyia mosquitoes (Diptera: Culicidae) present several operational limitations, which constitute major drawbacks to the epidemiological surveillance of arboviruses, the evaluation of the impact of control strategies, and the surveillance of the spreading of allochthonous species into non‐endemic regions. Here, we describe a new sticky trap designed to capture adult container‐breeding mosquitoes and to monitor their population dynamics. We tested the sampling properties of the sticky trap in Rome, Italy, where Aedes (Stegomyia) albopictus is common. The results of our observations, and the comparison between sticky trap catches and catches made with the standard oviposition trap, are presented. The sticky trap collected significantly larger numbers of Ae. albopictus females than any other Culicidae species representing >90% of the total catches. A maximum of 83 An. albopictus females was collected in a single week. A high correlation (Pearson correlation coefficient r= 0.96) was found between the number of females and the number of eggs collected by the traps. The functional relationship between the number of eggs and the number of adult females was assessed by major axis regression fitted to log(1 +x)‐transformed trap counts as y= 0.065 + 1.695x. Trap samples significantly departed from a random distribution; Taylor’s power law was fitted to the trap samples to quantify the degree of aggregation in the catches, returning the equations s2= 2.401 m1.325 for the sticky trap and s2= 13.068 m1.441 for the ovitrap, with s2 and m denoting the weekly catch variance and mean, respectively, indicating that eggs were significantly more aggregated than mosquitoes (P < 0.0001). Taylor’s power law parameters were used to estimate the minimum number of sample units necessary to obtain sample estimates with a fixed degree of precision and sensitivity. For the range of densities encountered in our study area during the Ae. albopictus breeding season, the sticky trap was more precise and sensitive than the ovitrap. At low population densities (c. < 0.1 mosquito/trap), however, the ovitrap was more sensitive at detecting the presence of this species. Overall, our results indicate that our new model of sticky trap can be used to sample Ae. albopictus females in urban environments, and, possibly, other container‐breeding Stegomyia mosquitoes (e.g. Aedes aegypti). The technical properties of the new trap are discussed with respect to its possible application in monitoring the population dynamics of container‐breeding mosquitoes, in studying their bionomics, and in vector surveillance and, possibly, control.
Rubidium marking of Anopheles mosquitoes detectable by field‐capable X‐ray spectrometry
Authors: WILKINS E. E. , SMITH S. C. , ROBERTS J. M. , BENEDICT M.
Published: June 2007

Abstract We present a mosquito marking technique suitable for mark‐release‐recapture that can be used with a hand‐held, portable X‐ray fluorescence (XRF) spectrometer, which is practical for field measurements. Third instar Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) and Anopheles stephensi Liston larvae were cultured to pupation in water containing rubidium (Rb) Cl at concentrations up to 1000 p.p.m. Rb. Anopheles gambiae larvae survived to adulthood at concentrations as high as 1000 p.p.m. Rb but suffered pupal mortality and reduced adult longevity at high concentrations. We were able to culture An. stephensi at Rb concentrations as high as 300 p.p.m. The presence of Rb in adults was evaluated using a portable XRF analyser, and we were able to reliably detect Rb above background levels in 10‐day‐old females and 4‐day‐old males at concentrations causing minimal pupal or adult mortality. We observed that Rb marking was not permanent, and the concentration declined significantly as adults aged. The low cost of labelling with RbCl and the field portability of the spectrometer provide a useful means for labelling mosquitoes via breeding sites or in the laboratory for mark‐release‐recapture experiments.
Variable switching rates of malaria virulence genes are associated with chromosomal position
Authors: Frank Matthias , Dzikowski Ron , Amulic Borko , Deitsch Kirk
Published: June 2007

Antigenic variation in Plasmodium falciparum malaria is mediated by transcriptional switches between different members of the multicopy var gene family. Each var gene encodes a member of a group of heterogeneous surface proteins collectively referred to as PfEMP1. Mutually exclusive expression ensures that an individual parasite only transcribes a single var gene at a time. In this work we studied var gene switching to determine if transcriptional switches favour expression of particular subgroups of var genes and if var gene activation within a clonal population of parasites follows a predetermined order. We show that in clonal parasite populations, expression of var genes located in the central regions of chromosomes is remarkably stable and that they rarely undergo transcriptional switches in the absence of selection. In contrast, parasites expressing subtelomerically located var genes readily switched to alternative var loci. We confirmed these observations by generating transgenic parasites carrying drug selectable markers in subtelomeric and central var loci and monitoring switching after release from selection. Our data show that different var genes have different intrinsic switching rates that correlate with chromosomal location, and that there is no predetermined order of expression.
Acquisition of a natural resistance gene renders a clinical strain of methicillin‐resistantStaphylococcus aureusresistant to the synthetic antibiotic linezolid
Authors: Toh Seok‐Ming , Xiong Liqun , Arias Cesar A. , Villegas Maria V. , Lolans Karen , Quinn John , Mankin Alexander S.
Published: June 2007

Linezolid, which targets the ribosome, is a new synthetic antibiotic that is used for treatment of infections caused by Gram‐positive pathogens. Clinical resistance to linezolid, so far, has been developing only slowly and has involved exclusively target site mutations. We have discovered that linezolid resistance in a methicillin‐resistantStaphylococcus aureushospital strain from Colombia is determined by the presence of thecfrgene whose product, Cfr methyltransferase, modifies adenosine at position 2503 in 23S rRNA in the large ribosomal subunit. The molecular model of the linezolid–ribosome complex reveals localization of A2503 within the drug binding site. The natural function ofcfrlikely involves protection against natural antibiotics whose site of action overlaps that of linezolid. In the chromosome of the clinical strain,cfris linked toermB, a gene responsible for dimethylation of A2058 in 23S rRNA. Coexpression of these two genes confers resistance to all the clinically relevant antibiotics that target the large ribosomal subunit. The association of theermB/cfroperon with transposon and plasmid genetic elements indicates its possible mobile nature. This is the first example of clinical resistance to the synthetic drug linezolid which involves a natural resistance gene with the capability of disseminating among Gram‐positive pathogenic strains.
The Mycobacterium tuberculosis FAS‐II condensing enzymes: their role in mycolic acid biosynthesis, acid‐fastness, pathogenesis and in future drug development
Authors: Bhatt Apoorva , Molle Virginie , Besra Gurdyal S. , Jacobs William R. , Kremer Laurent
Published: June 2007

Mycolic acids are very long‐chain fatty acids representing essential components of the mycobacterial cell wall. Considering their importance, characterization of key enzymes participating in mycolic acid biosynthesis not only allows an understanding of their role in the physiology of mycobacteria, but also might lead to the identification of new drug targets. Mycolates are synthesized by at least two discrete elongation systems, the type I and type II fatty acid synthases (FAS‐I and FAS‐II respectively). Among the FAS‐II components, the condensing enzymes that catalyse the formation of carbon‐carbon bonds have received considerable interest. Four condensases participate in initiation (mtFabH), elongation (KasA and KasB) and termination (Pks13) steps, leading to full‐length mycolates. We present the recent biochemical and structural data for these important enzymes. Special emphasis is given to their role in growth, intracellular survival, biofilm formation, as well as in the physiopathology of tuberculosis. Recent studies demonstrated that phosphorylation of these enzymes by mycobacterial kinases affects their activities. We propose here a model in which kinases that sense environmental changes can phosphorylate the condensing enzymes, thus representing a novel mechanism of regulating mycolic acid biosynthesis. Finally, we discuss the attractiveness of these enzymes as valid targets for future antituberculosis drug development.
Subcellular localization of Escherichia coli osmosensory transporter ProP: focus on cardiolipin membrane domains
Authors: Mileykovskaya Eugenia
Published: June 2007

The role for specific lipids in the spatial distribution of the membrane proteins and formation of the lipid‐protein membrane domains is an emerging theme in the studies of the supramolecular organization of the bacterial cell. A combination of the lipid and protein visualization techniques with manipulation of the cell lipid composition provides a useful tool for these studies. This MicroCommentary reviews the first experimental example demonstrating an involvement of the phospholipid cardiolipin in recruitment of a membrane protein (specifically H+‐osmoprotectant symporter ProP) to the Escherichia coli cell poles. The properties of cardiolipin domains employed in creating a specific environment for structural organization and function of membrane protein complexes are also discussed.
A novel lysis system in PM2, a lipid‐containing marine double‐stranded DNA bacteriophage
Authors: Krupovič Mart , Daugelavičius Rimantas , Bamford Dennis H.
Published: June 2007

In this study we investigated the lysis system of the lipid‐containing double‐stranded DNA bacteriophage PM2 infecting Gram‐negative marine Pseudoalteromonas species. We analysed wt and lysis‐deficient phage‐induced changes in the host physiology and ascribed functions to two PM2 gene products (gp) involved in lysis. We show that bacteriophage PM2 uses a novel system to disrupt the infected cell. The novelty is based on the following findings: (i) gp k is needed for the permeabilization of the cytoplasmic membrane and appears to play the role of a typical holin. However, its unique primary structure [53 aa, 1 transmembrane domain (TMD)] places it into a new class of holins. (ii) We have proposed that, unlike other bacteriophages studied, PM2 relies on lytic factors of the cellular origin for digestion of the peptidoglycan. (iii) gp l (51 aa, no TMDs) is needed for disruption of the outer membrane, which is highly rigidified by the divalent cations abundant in the marine environment. The gp l has no precedent in other phage lytic systems studied so far. However, the presence of open reading frame l‐like genes in genomes of other bacterial viruses suggests that the same system might be used by other phages and is not unique to PM2.
Sand as a medium for transmission of vibratory signals of prey in antlions Euroleon nostras (Neuroptera: Myrmeleontidae)
Authors: DEVETAK DUŠAN , MENCINGER‐VRAČKO BOJANA , DEVETAK MIHA , MARHL MARKO , ŠPERNJAK ANDREJA
Published: June 2007

Abstract European pit‐building antlions (Euroleon nostras/ Geoffroy in Fourcroy/) detect their prey by sensing the vibrations that prey generate during locomotory activity. The behavioural reactions and some of the physical properties of substrate vibrations in sand are measured to observe signal transmission through the substrate. The frequency range of the signals of four arthropod species (Tenebrio molitor, Pyrrhocoris apterus, Formica sp. and Trachelipus rathkei) is 0.1–4.5 kHz and acceleration values are in the range 400 μm s−2 to 1.5 mm s−2. Substrate particle size and the frequency of prey signals both influence the propagation properties of vibratory signals. The damping coefficient at a frequency 300 Hz varies from 0.26 to 2.61 dB cm−1 and is inversely proportional to the size of the sand particle. The damping coefficient is positively correlated with the frequency of the pulses. Vibrations in finer sand are attenuated more strongly than in coarser sand and, consequently, an antlion detects its prey only at a short distance. The reaction distance is defined as the distance of the prey from the centre of the pit when the antlion begins tossing sand as a reaction to the presence of prey. The mean reaction distance is 3.3 cm in the finest sand (particle size ≤ 0.23 mm) and 12.3 cm in coarser sand (particle size 1–1.54 mm). The most convenient sands for prey detection are considered to be medium particle‐sized sands.
Effects of nutrition and methoprene treatment upon reproductive diapause in Caloptilia fraxinella (Lepidoptera: Gracillariidae)
Authors: EVENDEN M. L. , ARMITAGE G. , LAU R.
Published: June 2007

Abstract Female Caloptilia fraxinella exhibit a prolonged reproductive diapause immediately post adult emergence in mid‐summer until the next spring when mating, egg development and oviposition on fresh Fraxinus spp. leaflets occur. Factors that effect the termination of reproductive diapause are investigated in this species. Caloptilia fraxinella diapausing adults held in overwintering conditions (2 °C, LD 0 : 24 h) for 24 weeks terminate diapause after placement for 2 weeks in simulated summer conditions (24 °C, LD 16 : 8 h) only if they are provided with 10% sugar water. Exogenous application of the Juvenile Hormone (JH) analogue methoprene to moths in both early‐ (summer) and mid‐ (autumn) reproductive diapause demonstrates that JH affects diapause termination but a carbohydrate nutrition source also mediates mating and vitellogenesis. Mating between moth pairs early in diapause occurs only after treatment with methoprene and provision with sugar water. However, there is no impact of mating on the propensity of females to produce vitellogenic oöcytes. Moths collected in the autumn in mid‐diapause respond in a dose‐dependent fashion to methoprene treatment and the response is greater than that of moths early in diapause collected in the summer. Treatment with methoprene and access to sugar water results in vitellogenic oöcytes in 18.75% of females from mid‐diapause moth pairs treated with 0.01 μg methoprene per insect and in all females from pairs treated at the two highest doses of methoprene (0.1 and 1 μg per insect). Mating occurs only between moths in mid‐diapause treated with the two highest doses of methoprene and these doses induce 91% and 100% mating, respectively. Both control and methoprene‐treated males in mid‐diapause held under summer conditions mate successfully and pass a spermatophore to their methoprene‐treated female partner. These data demonstrate that female C. fraxinella undergo a prolonged reproductive diapause in which termination is dependent on JH and further mediated by a carbohydrate nutrition source. The production of vitellogenic oöcytes is independent of mating. These data also provide evidence that response of moths in diapause to exogenous applications of methoprene differs throughout the diapause period and between male and female C. fraxinella.