Small vestibular schwannomas can cause gait instability

PURPOSE

To confirm whether detailed gait analysis can detect gait instability in patients with small vestibular schwannoma (VS) with an apparently normal gait.

METHODS

Twenty-two patients (7 males, 15 females; 40-64 years old) with small VS and nine healthy age- and weight-matched controls were enrolled. Small VS was defined as the longest diameter less than 20mm from the porus acusticus internus on MRI with no brainstem compression. Each subject was asked to walk straight for a distance of 8m with tactile sensors attached to both feet, and repeat two trials with eyes open and closed. Gait variables of stance, swing, double support, stability, and average length of the trajectories of the center of force (TCOF) during stance were recorded and analyzed.

RESULTS

No significant differences in the stability of the TCOF were found during gaits with eyes open and closed between the two groups. No obvious changes in gait variables were recognized with eyes open between the two groups. However, under gait with eyes closed, the values of the coefficient of variation (CV) of the gait phase were significantly greater in stance and swing in the VS group than in the normal group. In addition, patients with canal paresis (CP) showed greater CV values in gait phase related parameters than those who without CP during gait with eyes closed.

CONCLUSIONS

Patients with small VS may have an apparently normal gait, but their vestibular deficit could be detected by proper use of gait analysis, especially with visual deprivation.

A novel membrane based process to isolate photosystem-I membrane complex from spinach

The isolation of photosystem-I (PS-I) from spinach has been conducted using ultrafiltration with 300 kDa molecular weight cut-off polyethersulfone membranes. The effects of ultrafiltration operating conditions on PS-I activity were optimized using parameter scanning ultrafiltration. These conditions included solution pH, ionic strength, stirring speed, and permeate flux. The effects of detergent (Triton X-100 and n-dodecyl-beta-D-maltoside) concentration on time dependent activity of PS-I were also studied using an O(2) electrode. Under optimized conditions, the PS-I purity obtained in the retentate was about 84% and the activity recovery was greater than 94% after ultrafiltration. To our knowledge, this is the first report of the isolation of a membrane protein using ultrafiltration alone.

WITHDRAWN: Spinal d-amino acid oxidase contributes to the pathogenesis of hyperalgesia in the rat formalin test

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at (http://www.elsevier.com/locate/withdrawalpolicy.

Cryopreservation of embryogenic callus of Dioscorea bulbifera by vitrification

Cryopreservation of callus of Dioscorea bulbifera by vitrification was optimized. Calli of Dioscorea bulbifera were pretreated in liquid Murashige and Skoog (MS) medium supplemented with 2 mg L(-1) kinetin (KT), 0.5 mg L(-1) NAA, 0.5 mg L(-1) 2,4-D and 0.2 M sucrose for 5 d under continuous light (36 microM m(-2) s(-1)) at 25 + or - 1 degree C. The material was then loaded with 60 percent vitrification solution (PVS2) for 20 min at room temperature and dehydrated with 100 percent PVS2 for 30 min at 0 degree C. After changing the solution with fresh PVS2, the calli were directly immersed in liquid nitrogen and conserved for 1- 360 d. After rapid thawing in a water-bath at 35 degree C, the calli were washed three times with liquid MS medium supplemented with 2 mg L(-1) KT, 0.5 mg L(-1) NAA, 0.5 mg L(-1) 2, 4-D and 1.2 M sucrose and then transferred onto solid MS medium supplemented with KT 2 mg L(-1), NAA 0.5 mg per liter, 0.09 M sucrose and 0.75 percent agar. The cultures were kept in the dark for 2 days prior to exposure to the light (12 h light-dark cycle). The TTC test showed that 80-90 percent of the calli survived this cryoprocedure and there was a 60-70 percent regeneration of plantlets from the calli. The regenerated material did not exhibit any morphological variations.

Evaluation of the efficacy and safety of olopatadine and fexofenadine compared with placebo in Japanese cedar pollinosis using an environmental exposure unit

BACKGROUND

Second-generation oral H1-antihistamines have become a mainstay of treatment for the symptoms of seasonal allergic rhinitis; however, the effect of olopatadine has not been widely reported to date.

OBJECTIVES

To evaluate the efficacy of 2 oral H1-antihistamines, olopatadine and fexofenadine, in the treatment of the nasal symptoms of Japanese cedar pollinosis and their possible side effects.

METHODS

This was a randomized, double-blind, placebo-controlled, crossover study conducted in an environmental exposure unit (EEU). Twenty volunteers suffering from Japanese cedar pollinosis were randomly divided into 3 groups and exposed to cedar pollen in the EEU with oral administration of olopatadine hydrochloride (5 mg), fexofenadine hydrochloride (60 mg), or placebo 1 hour prior to pollen exposure. Nasal symptoms, activity impairment, and subjective sleepiness were self-assessed during the study period. Attention was measured using the digit cancellation test. The trial was repeated after 4 and 7 weeks.

RESULTS

Compared with placebo, olopatadine significantly improved nasal symptoms and activity impairment during pollen exposure (P < .05). There was no significant relief of nasal discharge or nasal congestion with fexofenadine throughout the 5-hour exposure to cedar pollen. Furthermore, olopatadine significantly reduced nasal congestion during the first 2 hours, as well as sneezing and nasal discharge 4 hours after admission to the EEU compared with fexofenadine (P < .05). There was no significant difference in the effect on subjective sleepiness among the 3 groups, and all 3 agents had little effect on attention.

CONCLUSIONS

These findings suggest that olopatadine is more effective than placebo and fexofenadine in improving nasal symptoms of Japanese cedar pollinosis.

Switch to an invasive growth phase in melanoma is associated with tenascin-C, fibronectin, and procollagen-I forming specific channel structures for invasion

Malignant melanomas are characterized by their high propensity to invade and metastasize, but the molecular mechanisms of these traits have remained elusive. Our DNA microarray analyses of benign nevi and melanoma tissue specimens revealed that the genes encoding extracellular matrix proteins tenascin-C (TN-C), fibronectin (FN), and procollagen-I (PCOL-I) are highly upregulated in invasive and metastatic melanomas. The expression and distribution of these proteins were further studied by immunohistochemistry in benign nevi, radially and vertically growing melanomas, sentinel node micrometastases, and macrometastases. TN-C was increased in all invasive tumours and metastases, especially at invasion fronts, but not in benign nevi or non-invasive melanomas. Significantly, the intensity of TN-C staining correlated with metastasis to sentinel lymph nodes, better than tumour thickness (Breslow). Moreover, TN-C, FN, and PCOL-I appeared to co-localize in the tumours and form tubular meshworks and channels ensheathing the melanoma cells. Our data suggest that melanoma invasion is associated with the formation of special channel-like structures, providing a new concept, structured tumour cell spreading. Altogether, these data provide potential new prognostic markers and therapeutic targets/strategies for preventing melanoma dissemination.

Varied presentations of pseudoxanthoma elasticum in a family

Pseudoxanthoma elasticum (PXE) is a hereditary disorder of elastic tissue. The characteristic skin changes are asymptomatic yellow papules around the neck and in body folds giving the skin a characteristic cobblestone appearance. The eyes, cardiovascular and gastrointestinal systems are also commonly involved. In this case-series, we present a family of four children, three of whom demonstrated diverse manifestations of PXE. The first child presented with sudden death at age 3 and showed marked coronary and renal arterial intimal fibrosis with prominent fragmentation of the internal elastic lamina, initially attributed to idiopathic arterial calcification. The second child presented with clinical features and histology of the skin typical of PXE at age 11 and the third child, with abnormal, but non-specific cardiological findings at age 8, which raised the possibility of an early stage of PXE. This report emphasizes the importance of considering pseudoxanthoma elasticum in diverse clinical settings, early diagnosis and appropriate screening for asymptomatic family members.

Sustained benefit in rheumatoid arthritis following one course of rituximab: improvements in physical function over 2 years

OBJECTIVES

To evaluate the long-term impact on physical function of a single course of rituximab in rheumatoid factor, seropositive patients with active rheumatoid arthritis (RA) despite ongoing methotrexate treatment.

METHODS

A randomized, controlled trial comparing rituximab alone [1,000 mg intravenously (iv) on days 1 and 15, n= 40], or in combination with cyclophosphamide (750 mg iv on days 3 and 7, n= 41) or oral methotrexate (> or =10 mg/week, n= 40) with placebo + methotrexate (> or =10 mg/week, n= 40), resulted in significant reductions in disease activity at weeks 24 and 48. Sustained improvements in physical function and standard effect sizes (SES) for changes in components of ACR and EULAR criteria were evaluated over 2 yrs.

RESULTS

More patients receiving rituximab + methotrexate completed a 2-yr follow-up without further treatment than those receiving placebo + methotrexate (45% vs 15%, respectively), rituximab alone (10%) or rituximab + cyclophosphamide (22%). This reflected a higher percentage of patients receiving rituximab + methotrexate reporting improvements in Health Assessment Questionnaire Disability Index > or = minimum clinically important difference at 1 and 2 yrs (68% and 30%, respectively) compared with placebo + methotrexate (28% and 15%), rituximab monotherapy (43% and 10%) or rituximab + cyclophosphamide (39% and 12%). SES were high in all rituximab groups and revealed differing patterns of response over time.

CONCLUSION

A single course of rituximab with continuing methotrexate in patients with active RA provided clinically meaningful improvements in physical function over 2 yrs, with lower discontinuation rates and larger SES for improvements in ACR and EULAR criteria components.

Severe colonic diverticulitis in an adolescent with Williams syndrome

Williams Syndrome (WS) is a condition with multisystemic involvement caused by a genetic deletion in chromosome 7. Colonic diverticulosis has been described in adults with WS; however, it has not previously been reported in adolescents with WS. We report an adolescent boy with WS who developed complicated colonic diverticulitis and briefly review the possible aetiology of diverticular disease.

URETHRAL POLYPS IN PREPUBERTAL GIRLS

PURPOSE

Urethral polyps in girls are included in the differential diagnosis of interlabial masses. Only 6 cases have been described in the English literature to date and etiology is uncertain. We present 5 more cases and review the literature. We also propose an etiology for urethral polyps in young girls and compare polyps between girls and boys as well as older females.

MATERIALS AND METHODS

The medical records of prepubertal girls with urethral polyps seen at our hospital between 1980 and 2003, including operative reports and followup, were reviewed. A senior pathologist re-inspected the specimens to confirm the diagnosis. A MEDLINE search of urethral polyps was performed.

RESULTS

We identified 5 girls 2 to 10 years old with urethral polyps. All girls presented with "vaginal" bleeding, 1 had recurrent urinary tract infections and vulvitis, 1 had urinary frequency, and 1 had painful voiding. The polyps were not site specific and were located in the distal, mid and proximal urethra. All polyps were excised and were found benign. Four girls were cured after 1 procedure, while in one girl the polyp reappeared. The patients were followed for 1 to 17 years and eventually became asymptomatic.

CONCLUSIONS

Urethral polyps in prepubertal girls are probably benign. We suggest that the etiology of most of polyps in girls is similar to those in older females, that is a prolapsing urothelium that has evolved into a polyp.

A systemic route for drug loading to lymphatic phagocytes

Lymph nodes are primary germination and proliferation sites for many types of pathogens. Maintaining therapeutic levels of appropriate chemotherapeutic agents in the lymph node tissue is critical for the treatment of both infection and cancer. This study was intended to develop a systemic route for loading lymph node phagocytes with drugs, using a lymph node specific nanocarrier. The latter is assembled as a 10-15 nm particle with a drug-carrying core and a phagocyte-homing poly(1-->6)-alpha-d-glucose based interface. Biokinetics and microdistribution of the model carrier were investigated in vivo. Nanocarrier accumulation in lymph nodes reached 30-35% dose/g in central lymph nodes, with deposition in various phagocytic cell populations. The latter included cells harboring inhaled microparticles translocated to lymph nodes from the lungs. In view of the nanocarrier ability to transport and release significant amounts of various drug substances, the data suggests feasibility of systemic drug loading to lymphatic phagocytes and, through drug release, to the neighboring cells.

Epitope DNA vaccines against tuberculosis: spacers and ubiquitin modulates cellular immune responses elicited by epitope DNA vaccine

Cell-mediated immune responses are crucial in the protection against tuberculosis. In this study, we constructed epitope DNA vaccines (p3-M-38) encoding cytotoxic T lymphocyte (CTL) epitopes of MPT64 and 38 kDa proteins of Mycobacterium tuberculosis. In order to observe the influence of spacer sequence (Ala-Ala-Tyr) or ubiquitin (UbGR) on the efficacy of the two CTL epitopes, we also constructed DNA vaccines, p3-M-S(spacer)-38, p3-Ub (UbGR)-M-S-38 and p3-Ub-M-38. The immune responses elicited by the four DNA vaccines were tested in C57BL/6 (H-2b) mice. The cytotoxicity of T cells was detected by LDH-release method and by enzyme-linked immunospot assay for epitope-specific cells secreting interferon-gamma. The results showed that DNA immunization with p3-M-38 vaccine could induce epitope-specific CD8+ CTL response and that the spacer sequence (AAY) only enhanced M epitope presentation. The protein-targeting sequence (UbGR) enhanced the immunogenicity of the two epitopes. The finding that defined spacer sequences at C-terminus and protein-targeting degradation modulated the immune response of epitope string DNA vaccines will be of importance for the further development of multi-epitope DNA vaccines against tuberculosis.

Off-line separation and determination of rare earth elements associated with chloroplast pigments of hyperaccumulator Dicranopteris dichotoma by normal-phase liquid chromatography and ICP?MS

An off-line normal-phase liquid chromatography-ICP-MS method has been used for separation and determination of the rare earth elements (REE) associated with chloroplast pigments of Dicranopteris dichotoma. The stability of REE-bound pigments was tested, and almost no destruction of REE-bound pigments occurred during the so-called normal-phase liquid chromatography. The accumulated free REE ions on the microcrystalline cellulose column were cleaned by elution with 5 mmol L(-1) 2-ethylhexyl hydrogen 2-ethylhexylphosphonate (P507), to avoid exchange of these free ions with metals from the pigments. When these precautions were taken, the method was applied to the study of REE-bound pigments in D. dichotoma. ICP-MS results showed REE were present in chlorophylls and lutein, although REE concentrations in carotene and pheophytin were both below procedural blank levels. By careful analysis of the eluate fractions containing chlorophyll a it was found that REE-bound chlorophyll a in D. dichotoma was slightly enriched in the fractions with relatively short retention time. Results indicated that the retention time of REE-bound chlorophyll a might be slightly less than that of magnesium chlorophyll a, and REE-bound chlorophylls might be of relatively low polarity in comparison with magnesium bound chlorophylls. This phenomenon could be explained by the special double-decker sandwich-structure of REE-bound chlorophylls, as was reported by us and other authors. On the basis of these results we preferred to consider that REE can replace magnesium in chlorophyll a of D. dichotoma, and that the role of REE-bound chlorophylls in photosynthesis cannot be neglected. These data might be useful for understanding of both the properties of REE-bound pigments and the effect of REE on plant photosynthesis.

Synthesis of a Macromolecular Camptothecin Conjugate with Dual Phase Drug Release

A water soluble macromolecular conjugate of camptothecin (CPT) with a new, dual phase hydrolytic drug release mechanism was prepared on the basis of a 60 kDa biodegradable hydrophilic "stealth" polyacetal, poly(1-hydroxymethylethylene hydroxy-methyl formal). Succinamido-glycinate was used as a prodrug releasing group. A model preparation with 7.5% CPT content w/w was water soluble. The lipophilic camptothecin prodrug, camptothecin-(O20)-succinimidoglycinate, was released from the conjugate with t(1/2) = 2.2 +/- 0.1 h in rodent plasma. The blood clearance in a rodent model as measured by CPT was release limited, t(1/2) = 2.1 +/- 0.2 h, while the conjugate half-life was 14.2 +/- 1.7 h. In a xenograft tumor model, the conjugate demonstrated higher antineoplastic efficacy than CPT at a less than equitoxic dose. This improved therapeutic window is in line with the modified drug pharmacokinetics and with camptothecin release in a stabilized lipophilic prodrug form. Regulation of prodrug release and hydrolysis rates through linker structure modification will open the way to further improve both pharmacokinetics and pharmacodynamics.