Effect of Limited Tenon Capsule and Intermuscular Membranes Dissection on the Outcome of Surgery in Patients with Horizontal Strabismus

Purpose: The aim of the study was to evaluate the effect of limited dissection of Tenon capsule on the outcome of strabismus surgery.

Methods: Patients between the ages of 2 and 50 years with pure horizontal strabismus were enrolled in a prospective study. Patients were divided into two groups: case and control as a non-randomized study. The method of operation was similar in both groups except for the amount of sheath Tenon dissection. In the control group the intermuscular connections and Tenon capsule were cut as much as possible. In the study group, Tenon capsule, 3-4 mm posterior to the location of the sutures over the muscle (recessed or resected), were cut and intermuscular connections remained intact.

Results: The study enrolled 54 patients with 27 patients in each group. In both groups, after operation, regardless of the type of surgery, the angle of strabismus was reduced (P< 0.05). For patients who had undergone bimedial recession, the angle of strabismus was corrected to 2.6 ± 0.4 prism diopters per mm (PD/mm) of muscle recession in the case group, and 2.2 ± 0.9 in the control group (P=0.2). For patients who had undergone monocular recession and resection (R&R) for esotropia, the angle of strabismus was corrected 3.4 ± 0.3 PD/mm of muscle recession or resection in the case group, and 3.2 ± 0.2 in the control group (P=0.05). For patients who had undergone bilateral recession, the angle of strabismus was corrected 2.3 ± 0.2 PD/mm of muscle recession in the case group, and 2.2±0.2 in the control group (P=0.03). For patients who had undergone R&R for exotropia, the angle of strabismus was corrected 3.1 ± 0.5 PD/mm of muscle recession or resection in the case group, and 2.7 ± 0.3 in the control group (P=0.02).

Conclusion: Connective tissue ensheathments, whether disturbed or removed, do not ultimately affect the success of the strabismus surgery.     

An in vitro comparison of bacterial leakage of three common restorative materials used as an intracoronal barrier

The purpose of this in vitro study was to evaluate quantitatively the effectiveness of three different restorative materials used as an intracoronal barrier to prevent microleakage of endodontically treated teeth. Fifty-five extracted human single-canal teeth were used in this study. The teeth were endodontically prepared and obturated. Forty-five teeth were randomly assigned to three experimental groups: group 1: sealed with Ketac-Cem (3M ESPE, St Paul, MN) (n = 15), group 2: sealed with Clearfil Protect Bond/Clearfil AP-X (Kuraray, New York, NY) (n = 15), and group 3: sealed with Maxcem (Kerr, Orange, CA) (n = 15). Ten teeth were also randomly assigned to a negative control group (n = 5) and a positive control group (n = 5). Microleakage was tested by using a sterile two-chamber bacterial method and Enterococcus faecalis was used as a microbial marker. Samples were incubated aerobically at 37 degrees C for 120 days. Bacterial leakage was determined by change in turbidity in the medium. Statistical analysis was performed using a Wald chi-square test. No significant difference (p > 0.05) in bacterial leakage was found between the three experimental groups tested. All positive controls leaked within 60 days and broth of the negative control group remained clear throughout the entire experimental period.     

Yeast Cell as a Bio-Model for Measuring the Toxicity of Fish-Killing Flagellates

Harmful algal blooms are a significant environmental problem. Cells that bloom are often associated with intercellular or dissolved toxins that are a grave concern to humans. However, cells may also excrete compounds that are beneficial to their competition, allowing the cells to establish or maintain cells in bloom conditions. Here, we develop a yeast cell assay to assess whether the bloom-forming species can change the toxicity of the water environment. The current methods of assessing toxicity involve whole organisms. Here, yeast cells are used as a bioassay model to evaluate eukaryotic cell toxicity. Yeast is a commonly used, easy to maintain bioassay species that is free from ethical concerns, yet is sensitive to a wide array of metabolic and membrane-modulating agents. Compared to methods in which the whole organism is used, this method offers rapid and convenient cytotoxicity measurements using a lower volume of samples. The flow cytometer was employed in this toxicology assessment to measure the number of dead cells using alive/dead stain analysis. The results show that yeast cells were metabolically damaged after 1 h of exposure to our model toxin-producing euryhaline flagellates (Heterosigma akashiwo and Prymnesium parvum) cells or extracts. This amount was increased by extending the incubation time.     

Injectable citrate-based mussel-inspired tissue bioadhesives with high wet strength for sutureless wound closure

The existing surgical adhesives are not ideal for wet tissue adhesion required in many surgeries such as those for internal organs. Developing surgical adhesives with strong wet tissue adhesion, controlled degradability and mechanical properties, and excellent biocompatibility has been a significant challenge. Herein, learning from nature, we report a one-step synthesis of a family of injectable citrate-based mussel-inspired bioadhesives (iCMBAs) for surgical use. Within the formulations investigated, iCMBAs showed 2.5-8.0 folds stronger wet tissue adhesion strength over the clinically used fibrin glue, demonstrated controlled degradability and tissue-like elastomeric mechanical properties, and exhibited excellent cyto/tissue-compatibility both in?vitro and in?vivo. iCMBAs were able to stop bleeding instantly and suturelessly, and close wounds (2?cm long?×?0.5?cm deep) created on the back of Sprague-Dawley rats, which is impossible when using existing gold standard, fibrin glue, due to its weak wet tissue adhesion strength. Equally important, the new bioadhesives facilitate wound healing, and are completely degraded and absorbed without eliciting significant inflammatory response. Our results support that iCMBA technology is highly translational and could have broad impact on surgeries where surgical tissue adhesives, sealants, and hemostatic agents are used.     

Secondary chemotherapy for high-risk gestational trophoblastic neoplasia

OBJECTIVE: To determine the efficacy of secondary chemotherapy after failure of initial treatment for high-risk gestational trophoblastic neoplasia. METHODS: Twenty-six patients with high-risk gestational trophoblastic neoplasia based on WHO criteria who failed primary treatment or relapsed from remission and received secondary chemotherapy were identified from the records of the Brewer Trophoblastic Disease Center. Initial chemotherapy consisted of etoposide, high-dose methotrexate with folinic acid, actinomycin D, cyclophosphamide and vincristine (EMA-CO) in 10 patients and methotrexate/actinomycin D-based chemotherapy without etoposide in 16 patients. Secondary chemotherapy consisted mainly of platinum-etoposide combinations with methotrexate and actinomycin D (EMA-EP), bleomycin (BEP), or ifosfamide (VIP, ICE). Adjuvant surgery and radiotherapy were used in selected patients. Clinical response and survival as well as factors affecting survival were analyzed retrospectively. RESULTS: The overall survival has 61.5% (16/26). Of the 10 patients who failed primary treatment with EMA-CO, 9 (90%) had complete clinical responses to secondary chemotherapy with EMA-EP (3) or BEP (6), and 6 (60%) were placed into lasting remission. Of the 16 patients who failed primary treatment with methotrexate/actinomycin D-based chemotherapy without etoposide, 10 (63%) had complete clinical responses to BEP (8), VIP (1) and ICE (1), and 10 (63%) achieved long-term remission. Adjuvant surgical procedures were performed on 15 patients as a component of their therapy; eight (73%) of 11 patients who underwent hysterectomy, five (62%) of eight patients who had pulmonary resections, and one patient who had wedge resection of resistant choriocarcinoma from the uterus survived. Survival was significantly influenced by both hCG level at the start of secondary therapy and sites of metastases. CONCLUSION: Patients with persistent or recurrent high-risk gestational trophoblastic neoplasia who develop resistance to methotrexate-containing treatment protocols should be treated with drug combinations employing a platinum agent and etoposide with or without bleomycin or ifosfamide.     

Top-Cited Articles in Rehabilitation

Shadgan B, Roig M, HajGhanbari B, Reid WD. Top-cited articles in rehabilitation.

Objective

To identify the 100 top-cited articles ever published in rehabilitation journals and to analyze their characteristics as a quantitative approach to investigating the quality and evolution of rehabilitation research.

Data Sources

The Institute for Scientific Information Web of Knowledge Database and the 2007 and 2008 Journal Citation Report Science Editions were used to retrieve the 100 top-cited articles from 30 rehabilitation dedicated journals.

Study Selection

The 100 top-cited articles included randomized controlled trials, case-control studies, case series studies, case reports, methodologic studies, systematic reviews, narrative reviews, and expert opinions.

Data Extraction

Two independent reviewers performed data extraction from the retrieved articles and compared their results. The Sackett's initial rules of evidence were used to categorize the type of study design as well as to evaluate the level of evidence provided by the results of the 100 top-cited articles.

Data Synthesis

Among the 45,700 articles published in these journals, the 100 top-cited articles were published between 1959 and 2002 with an average of 200 citations an article (range, 131-1109). Top-cited articles were all English-language, primarily from North America (United States=67%; Canada=11%) and published in 11 journals led by the Archives of Physical Medicine and Rehabilitation. Eighty-four percent of the articles were original publications and were most commonly prospective (76%) case series studies (67%) that used human subjects (96%) providing level 4 evidence. Neurorehabilitation (41%), disability (19%), and biomechanics (18%) were the most common fields of study.

Conclusions

We demonstrated that methodologic observational studies performed in North America and published in English have had the highest citations in rehabilitation journals.