Repair Sequences Research Articles

The Optimal Sequence of Microvascular Repair during Prolonged Clamping in Free Flap Transfer

The Optimal Sequence of Microvascular Repair during Prolonged Clamping in Free Flap Transfer

Evaluation of a training programme to facilitate conversation between people with aphasia and their partners

Background: The investigation into conversational interaction in aphasia and its therapeutic implications has received much interest. It is increasingly accepted that people with aphasia cannot be treated in isolation but as part of a social unit. Training conversation partners has been shown to impact on the disabling effect of aphasia. Aims: The principal aim of this study was to evaluate a programme designed to train a relative/friend to communicate more effectively with an aphasic partner. The intervention was assessed in terms of effects on communication and on wellbeing. Methods & Procedures: Four single-case studies were completed. The aphasic participants had severe impairment affecting both comprehension and expression. The baseline was a series of three assessments. The dyads were videotaped having a conversation, and completed a Visual Assessment for Self-Esteem Scale (VASES). The non-aphasic partner also completed a Hospital Anxiety and Depression Scale (HADS). The training programme ran for 5 weeks (1.5 hours/week) at the couples' homes. It included education, video feedback, and role-play. The initial assessments were repeated post-intervention. Outcomes & Results: Conversation data were subject to a conversation analysis as well as frequency counts of nonverbal behaviours. We found positive individual changes and positive trends: three of the four dyads increased their use of gesture and the proportion of successful repair sequences increased post-intervention, although these changes were not statistically significant. There were no significant differences for the HADS but there were differences between the aphasics and the non-aphasics on the VASES. Conclusions: The positive trends suggest that working with couples can produce beneficial effects. Future research may help establish who will benefit from this approach and the optimal number of sessions.

Excision of misincorporated ribonucleotides in DNA by RNase H (type 2) and FEN-1 in cell-free extracts.

Misincorporated ribonucleotides in DNA will cause DNA backbone distortion and may be targeted by DNA repair enzymes. Using double-stranded oligonucleotide probes containing a single ribose, we demonstrate a robust activity in human, yeast, and Escherichia coli cell-free extracts that nicks 5' of the ribose. The human and yeast extracts also make a subsequent cut 3' of the ribonucleotide releasing a ribonucleotide monophosphate. The resulting 1-nt gap is an ideal substrate for polymerase and ligase to complete a proposed repair sequence that effectively replaces the ribose with deoxyribose. Screening of yeast deletion mutant cells reveals that the initial nick is made by RNase H(35), a RNase H type 2 enzyme, and the second cut is made by Rad27p, the yeast homologue of human FEN-1 protein. RNase H type 2 enzymes are present in all kingdoms of life and are evolutionarily well conserved. We knocked out the corresponding rnhb gene in E. coli and show that extracts from this strain lack the nicking activity. Conversely, a highly purified archaeal RNase HII type 2 protein has a pronounced activity. To study substrate specificity, extracts were made from a yeast double mutant lacking the other main RNase H enzymes [RNase H1 and RNase H(70)], while maintaining RNase H(35). It was found that a single ribose is preferred as substrate over a stretch of riboses, further strengthening a proposed role of this enzyme in the repair of misincorporated ribonucleotides rather than (or in addition to) processing RNADNA hybrid molecules.

Physiological and biomechanical principles in splinting the traumatised hands.

The aim of this article is to review the biological sequence of wound repair and the rationale of using splintage to modify the healing process. Appropriate use of splintage and controlled stress can prevent adhesion and periarticular fibrosis. Splinting prescribed at appropriate timing and methods will enhance wound healing and tissue remodelling. In reverse, it will cause permanent damage to the tissues.

Fractures with major vascular injuries from gunshot wounds: implications of surgical sequence.

The sequence of surgical repair for penetrating extremity injuries requiring both vascular repair and fracture fixation is controversial. The optimal determination of repair order and its consequences is the purpose of this study. A retrospective review was performed of 27 patients over a 10-year period requiring acute revascularization and fracture fixation for isolated gunshot wound injuries. Injuries to the brachial artery and the femoral and popliteal vessels with accompanying fractures requiring operative stabilization were considered. The Mangled Extremity Severity Score, surgical sequence, limb viability, fasciotomy, incidence of iatrogenic vascular repair disruption, and length of hospitalization were analyzed. There were 17 lower and 10 upper extremity injuries, with a mean Mangled Extremity Severity Score of 4.1. Fracture fixation preceded vascular repair in five cases, whereas revascularization preceded bone fixation in 22 cases. A temporary vascular shunt was used in 13 and definitive vascular repair with used in 9 patients. There were no cases of vascular repair, shunt disruption, or amputation after fracture fixation. Four of five (80%) patients with orthopedic fixation before revascularization required fasciotomies, whereas 8 of 22 (36%) patients with revascularization before fixation required fasciotomies, and this difference approached significance (p = 0.10). Patients with fasciotomies had a significantly longer mean length of hospitalization, 18.3 +/- 8.6 days compared with 10.8 +/- 8.1 days (p = 0.03). CONCLUSION For patients with combined injuries, priority should be given to revascularization before orthopedic fixation because of shorter hospitalization and a trend toward lower fasciotomy rates. Revascularization before fracture fixation did not result in iatrogenic disruption of the vascular repair.

The temporal sequence of spontaneous repair of osteochondral defects in the knees of rabbits is dependent on the geometry of the defect.

Damage to articular cartilage is a common injury, for which there is no effective treatment. Our aims were to investigate the temporal sequence of the repair of articular cartilage and to define a critical-size defect. Full-thickness defects were made in adult male New Zealand white rabbits. The diameter (1 to 4 mm) of the defects was varied in order to determine the effect that the size and depth of the defect had on its healing. The defects were made in the femoral groove of the knee with one defect per knee and eight knees per group. The tissues were fixed in formalin at days 3, 7, 14, 21, 28, 42, 84 and 126 after operation and the sections stained with Toluidine Blue. These were then examined and evaluated for several parameters including the degree of metachromasia and the amount of subchondral bone which had reformed in the defect. The defects had a characteristic pattern of healing which differed at different days and for different sizes of defect. Specifically, the defects of 1 mm first peaked in terms of metachromasia at day 21, those of 2 mm at day 28, followed by defects of 3 mm and 4 mm. The healing of the subchondral bone was slowest in defects of 1 mm.

The temporal sequence of spontaneous repair of osteochondral defects in the knees of rabbits is dependent on the geometry of the defect

Damage to articular cartilage is a common injury, for which there is no effective treatment. Our aims were to investigate the temporal sequence of the repair of articular cartilage and to define a critical-size defect. Full-thickness defects were made in adult male New Zealand white rabbits. The diameter (1 to 4 mm) of the defects was varied in order to determine the effect that the size and depth of the defect had on its healing. The defects were made in the femoral groove of the knee with one defect per knee and eight knees per group. The tissues were fixed in formalin at days 3, 7, 14, 21, 28, 42, 84 and 126 after operation and the sections stained with Toluidine Blue. These were then examined and evaluated for several parameters including the degree of metachromasia and the amount of subchondral bone which had reformed in the defect. The defects had a characteristic pattern of healing which differed at different days and for different sizes of defect. Specifically, the defects of 1 mm first peaked in terms of metachromasia at day 21, those of 2 mm at day 28, followed by defects of 3 mm and 4 mm. The healing of the subchondral bone was slowest in defects of 1 mm.

Repair Sequences in Spanish L2 Dyadic Discourse: A Descriptive Study

This article reports on a qualitative study of dyadic discourse between university students of Spanish as a foreign language (FL). In light of the common acceptance of pair work as an effective pedagogical practice in the FL classroom, the study was designed to explore the social and cognitive behavior of learners as they participated in second language speaking activities. The construct of repair as it is formulated in the ethnomethodological approach to conversation analysis provided the lens through which data were examined. Trouble sources were identified and repair sequences were classified in terms of which learner brought attention to the trouble source and which learner resolved it. A clear preference for self‐repair and for self‐initiated repair was found. Collaborative repair, as well as unsolicited other‐repair, operated almost exclusively on the lexicon, whereas self‐initiated self‐repair included morphosyntax. The study supports the Vygotskian notion that talk is used for cognitive as well as for social purposes.

Aspects of TBC service experience in aero engines

The frame conditions to apply advanced materials technologies in aero engines are envisaged from view point of an aircraft operator and performer of allocated maintenance repair and overhaul activities. Main targets are the reliable operation of the parts, the steady ecological improvement during operation and the reduction on overall cost per flight hour based on increased knowledge. The application of Thermal Barrier Coatings (TBCs) may contribute to reach these goals. They may - for example - add to optimised operation by reducing fuel consumption and by protecting important engine parts. The principles of a long term engine parts operation and repair philosophy are outlined to clarify the property requirements for reliable engine operation. Typical TBC-protected components within actually operated civil aero engines are described. Silicate deposition on a HTP Blade and erosive attack of TBC is introduced exemplarily. A repair sequence to counteract surface degradation is introduced.

Specialized Corrective Repair Sequences: Shared Book Reading With Children With Histories of Specific Language Impairment

In this article, we examine parents' specialized corrective repair sequences during shared book reading with 4 children with histories of specific language impairment. First, we describe how parents achieve correction interactionally with other-initiated repair, both with and without invitations for the children to self-correct. Next, we show how parents use a variety of sequential organizations to accomplish other-initiated repair and invite self-correction from their children. Finally, we show how dyads with older and younger children use corrective repair in different frequencies and elaborations of sequential organizations.

Some Contributions of Empirical Infant Research to Adult Psychoanalysis: What Have We Learned? How Can We Apply It?

The direct links among early development, a model of the mind, and the content of the transference are challenged from two vantage points—empirical infant research and motivational systems theory. A discussion of these contributions and of their application in two case vignettes suggests a new view of therapeutic change—a view involving (a) recognition of the coconstruction of the analytic relationship, (b) contributions of self- and interactive regulations, of their disruption and repair, and of heightened affective moments to the ongoing analyst-patient interchange, (c) emphasis on the analyst's recognition of the patient's communications as developmental strivings, (d) tracking of sequences of disruption and repair, and (e) dialectic between repetition and transformation. These various interactions develop in a patient new expectations of being understood, of being understandable, and of participating in a dialogue that does not, for example, require bolstering the other or sacrificing oneself to the other. These new expectations lead to new themes as well as to the transformation of old themes that organize experience.

Vascular Injuries of the Upper Extremity

Vascular injuries of the upper extremity represent approximately 30% to 50% of all peripheral vascular injuries. The majority of injuries are to the brachial artery, and 90% of injuries are due to penetrating trauma. Return of function is often related to concomitant injury to peripheral nerves. However, timely restoration of blood flow is essential to optimize outcome. The diagnosis is made by physical examination and limited Doppler ultrasonography. Arteriography may be helpful if there are multiple sites of injury. Anticoagulation with heparin should be given if not otherwise contraindicated. Revascularization should be completed within the critical ischemic time: 4 hours for proximate injuries and 12 hours for distal injuries. Revascularization methods include resection and primary repair or resection with an interposition graft. The sequence of repair of multiple injuries to the extremity begins with arterial revascularization followed by skeletal stabilization and nerve and tendon repair.

Vascular Injuries of the Upper Extremity

Vascular injuries of the upper extremity represent approximately 30% to 50% of all peripheral vascular injuries. The majority of injuries are to the brachial artery, and 90% of injuries are due to penetrating trauma. Return of function is often related to concomitant injury to peripheral nerves. However, timely restoration of blood flow is essential to optimize outcome. The diagnosis is made by physical examination and limited Doppler ultrasonography. Arteriography may be helpful if there are multiple sites of injury. Anticoagulation with heparin should be given if not otherwise contraindicated. Revascularization should be completed within the critical ischemic time: 4 hours for proximate injuries and 12 hours for distal injuries. Revascularization methods include resection and primary repair or resection with an interposition graft. The sequence of repair of multiple injuries to the extremity begins with arterial revascularization followed by skeletal stabilization and nerve and tendon repair.

The importance of clinicopathological correlation in the diagnosis of inflammatory conditions of the colon: histological patterns with clinical implications.

Histological reaction patterns within the colon are not disease-specific but reflect mechanisms of injury and duration of disease. By correlating these patterns with known causes of colonic inflammation, we provide guidelines to enhance the diagnostic value of colonoscopic samples. Normal histological features are reviewed, and the sequence of inflammation and repair is used as the basis for appreciating pathological deviations. The common histological patterns of acute colitis with and without features of pseudomembranous or ischemic colitis and the morphological features of chronic colitis with and without crypt destruction are collated with clinical and endoscopic features to emphasize the importance of dialogue between the pathologist and gastroenterologist. Less common patterns, including eosinophilic colitis, graft-versus-host disease, chronic mucosal prolapse, portal hypertensive colopathy, and nonspecific or idiopathic ulcer, illustrate variations in the basic reaction patterns. Difficulties in differential diagnosis are underscored, and biopsy strategies are suggested.

A double-strand break in a chromosomal LINE element can be repaired by gene conversion with various endogenous LINE elements in mouse cells.

A double-strand break (DSB) in the mammalian genome has been shown to be a very potent signal for the cell to activate repair processes. Two different types of repair have been identified in mammalian cells. Broken ends can be rejoined with or without loss or addition of DNA or, alternatively, a homologous template can be used to repair the break. For most genomic sequences the latter event would involve allelic sequences present on the sister chromatid or homologous chromosome. However, since more than 30% of our genome consists of repetitive sequences, these would have the option of using nonallelic sequences for homologous repair. This could have an impact on the evolution of these sequences and of the genome itself. We have designed an assay to look at the repair of DSBs in LINE-1 (L1) elements which number 10(5) copies distributed throughout the genome of all mammals. We introduced into the genome of mouse epithelial cells an L1 element with an I-SceI endonuclease site. We induced DSBs at the I-SceI site and determined their mechanism of repair. We found that in over 95% of cases, the DSBs were repaired by an end-joining process. However, in almost 1% of cases, we found strong evidence for repair involving gene conversion with various endogenous L1 elements, with some being used preferentially. In particular, the T(F) family and the L1Md-A2 subfamily, which are the most active in retrotransposition, appeared to be contributing the most in this process. The degree of homology did not seem to be a determining factor in the selection of the endogenous elements used for repair but may be based instead on accessibility. Considering their abundance and dispersion, gene conversion between repetitive elements may be occurring frequently enough to be playing a role in their evolution.

Midface fractures.

Fractures of the middle portion of the facial skeleton are commonly referred to as midface or LeFort fractures. While significant progress has been made in terms of evaluation and treatment of such fractures, they remain a challenge for the maxillofacial surgeon. In this section, we will review the principles of midface fracture evaluation and repair, emphasizing the importance of understanding biomechanics and controversies that exist in respect to repair sequencing.

The Organization of Second Language Classroom Repair

This paper presents an analysis of the repair mechanism in second language classroom talk. More specifically, the current paper focuses on how co-participants (i.e., the teacher and the learners) carry out repair operations on the trouble source produced by the learner in the second language instructed talk-in-interaction. The present findings show that participation frameworks (i.e., types of activities) play an important role in constructing repair sequences in the instructional context. When learners engage in role-playing activities with one another, a wide variety of repair sequences are manifested, such as self-initiated and self-completed, self-initiated and other-completed, and other-initiated and other- completed repair sequences.The collaborative nature of repair sequences is also manifested in learner role-playing activities, in which self-initiation of the trouble source by the learner is collaboratively completed withco-participants in the form of word search and try-marking. Other-initiated and other-completed repair in learner role-playing activities is manifested in the form of cluing, which is accompanied by the sequence of teacher's initiation, learner's response, and teacher's evaluation (i.e., IRE sequence). Teacher-fronted activities, on the other hand, in which a teacher asks a question to learner(s), are mainly characterized by other-initiated and other-completed repair structures in the form of IRE sequence and unmodulated"no." Furthermore, a close examination of learners' responses to the teacher's repair (e.g., recast) reveals the key role of activity types operating in L2 instructional discourse.

Hearing-impaired children's strategies for managing communication breakdowns

AbstractThis article discusses communication breakdowns and strategies that are used to repair them. It focuses on other-initiated repair sequences (Brinton and Fujiki, 1989), such as when a listener fails to understand a speaker's utterance and indicates this by making a clarification request. Following the clarification request the speaker then tries to repair the communication breakdown. Both specific and non-specific clarification requests are discussed as devices for signalling communication breakdowns and initiating repair. Repetition and revision are discussed as repair strategies. The literature on the strategies of hearing-impaired children for managing communication breakdowns is then reviewed with reference to three research methodologies: naturalistic, elicitation and referential communication research. An approach to the assessment and development of the strategies of hearing-impaired children for managing communication breakdown is then suggested, based on the referential communication resea...

Hearing-impaired children's strategies for managing communication breakdowns

This article discusses communication breakdowns and strategies that are used to repair them. It focuses on other-initiated repair sequences (Brinton and Fujiki, 1989), such as when a listener fails to understand a speaker's utterance and indicates this by making a clarification request. Following the clarification request the speaker then tries to repair the communication breakdown. Both specific and non-specific clarification requests are discussed as devices for signalling communication breakdowns and initiating repair. Repetition and revision are discussed as repair strategies. The literature on the strategies of hearing-impaired children for managing communication breakdowns is then reviewed with reference to three research methodologies: naturalistic, elicitation and referential communication research. An approach to the assessment and development of the strategies of hearing-impaired children for managing communication breakdown is then suggested, based on the referential communication research of P. Lloyd (1991, 1992, 1993).

Mutation Spectrum Induced by Singlet Oxygen in Escherichia coli Deficient in Exonuclease III

The repair of singlet oxygen (1O2)-induced DNA lesions requires several enzymes of the nucleotide and base excision repair pathways, including exonuclease III and endonuclease IV that are known apurinic/apyrimidinic-endonucleases in Escherichia coli. In order to better understand the relevance of exonuclease III on the repair of these lesions, we investigated the mutagenic events that result from the replication of a 1O2-damaged plasmid in an exonuclease-deficient host (xth). The mutation spectrum in the tRNA supF gene target indicated that the absence of exonuclease III does not change the types of mutations induced by 1O2 (mostly of G:C-->T:A and G:C-->C:G transversions). However, the spectrum shows that the mutations are scattered in the supF gene, which is significatively different from the one obtained in wild-type bacteria. Thus, exonuclease III may act on the repair of 1O2-induced lesions altering the DNA repair sequence specificity.