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A Benson

Publications and source records attributed to A Benson.

At least 19 recordsLinked to original sources
PubMed2006

Comparative genomics of the lactic acid bacteria.

Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

Animals↗
PubMed2004

Understanding the social context of violent and aggressive incidents on an inpatient unit.

The English National Service Framework for Mental Health stipulates that the highest quality of health care should be provided for mental health service users. Incidents of aggression and violence militate against achieving that goal, yet such incidents are frequently reported in inpatient settings. Much research in this area reflects a dualistic, perpetrator/victim conceptualization of incidents. This study aimed to take a more systemic approach by treating violent and aggressive incidents as social interactions and by seeking to understand the social contexts in which they took place. In this paper we describe and discuss the main themes to emerge from 15 staff accounts of 11 incidents on one ward. A striking theme reflected throughout the interview data was the lack of staff engagement with clients, and particularly an inability to look at the world through clients' eyes in interpreting their behaviour. We conclude that the 'zero tolerance' campaigns currently being conducted in the UK in relation to aggression towards NHS staff are unlikely to succeed without attention to understanding why aggressive behaviour arises and identifying features of the caring environment that may contribute to it. Rather than adopting a position of 'zero tolerance', we argue that three steps are required following an aggressive incident: emotional support; critical reflection and learning; and the pursuit of accountability.

Aggression↗
PubMed2003

The clients' experience of the community group: implications for nurse facilitators.

Community or large group meetings occur in many mental health units. Literature is available that describes the possible functions of such groups, but little is known about how they are actually experienced by the members, or the implications of this for nurse facilitators, especially in the current context of inpatient care. The aim of this study was to develop an understanding of the clients' experience of the daily community group in a unit that offered both an inpatient and a day patient service for adults experiencing mental health problems. The group meeting was intended to provide an opportunity for people to examine their relationships with others and discover new ways of coping with problems and stressors. The group had a changing membership, with all staff and clients present on the unit at the time expected to attend. The meeting lasted for an hour and had no predetermined agenda. Mental health nurses made up the majority of the staff membership. Semistructured interviews were conducted with four clients who had been attending the group for between 3 and 6 months. These were tape recorded, transcribed verbatim and then analysed using the phenomenological approach of Colaizzi. Three themes emerged from the data: 'Whose Responsibility?', 'Me vs. Them' and 'What Works?' These themes have implications for nurse facilitators, namely: their awareness that such issues are of importance; their ability to recognize how and when they are present; and their ability to effectively intervene.

Community Health Services↗
PubMed2001

Familial pulmonary carcinoid tumors.

BACKGROUND: Pulmonary carcinoid tumors are rare and usually occur sporadically. Infrequently, they arise in association with multiple endocrine neoplasia type 1 (MEN1). Familial pulmonary carcinoid tumors not associated with MEN1 have not been described. METHODS: Two sets of first-degree relatives diagnosed with primary pulmonary carcinoid tumors with no clinical features of MEN1 were identified in a pair of siblings and in a mother and daughter. Mutations in the MEN1 gene were sought using polymerase chain reaction analysis on paraffin embedded tissue from two members of one of the families. RESULTS: Histopathologic and immunohistochemical studies confirmed the diagnoses of carcinoid tumors. None of these patients and no family members had features of MEN1. DNA analysis did not detect germline mutations in the MEN1 gene. CONCLUSIONS: The occurrence of familial pulmonary carcinoid tumors in the absence of MEN1 suggests a novel, rare germline mutation specific to the development of pulmonary carcinoids.

Adult↗
PubMed1999

A phase II study of 5-fluorouracil, leucovorin, and interferon-alpha in the treatment of patients with metastatic or recurrent gastric carcinoma: an Eastern Cooperative Oncology Group study (E5292).

BACKGROUND: Chemotherapy has a limited impact on adenocarcinoma of the stomach. Although biochemical modulation of 5-fluorouracil (5-FU) by leucovorin (LV) and interferon-alpha (IFN-alpha) has improved the outcomes of patients with metastatic colorectal carcinoma compared with 5-FU alone, this approach has not been extensively evaluated in the treatment of advanced gastric carcinoma. METHODS: Twenty-seven patients with bidimensionally measurable, metastatic gastric carcinoma and an Eastern Cooperative Oncology Group performance status of 0 or 1 received the combination of IFN-alpha (5 million U/m2 administered subcutaneously daily on Days 1-7), LV (500 mg/m2 administered intravenously over 30 minutes immediately after IFN-alpha on Days 2-6), and 5-FU (370 mg/m2 given as an intravenous bolus 60 minutes after LV on Days 2-6), with treatment repeated every 4 weeks. Oral cryotherapy was administered routinely before each dose of 5-FU to reduce the incidence of severe stomatitis. RESULTS: The median age of the patients was 58 years (range, 20-76), and 22 patients had residual, unresectable primary lesions. The median number of cycles received was 3 (range, 1-11). Of 24 patients who received at least 2 cycles of treatment, 15 (62.5%) did not require dose reduction for toxicity during the initial 2 cycles. The predominant toxicities were gastrointestinal: diarrhea and stomatitis of Grade 3-4 occurred in 28.6% and 35.7% of patients, respectively. Other severe (Grade 3-4) toxicities were granulocytopenia (which occurred in 21.4% of patients) and fatigue (in 10.7%). Fever and flu-like symptoms were common but usually mild. Of 24 patients who were evaluable for response, 3 had partial responses (PR) of 16, 23, and 33 weeks' duration, respectively, for a response rate of 12.5% (95% confidence interval = 2.7-32.4%). Two additional patients had reductions in tumor size sufficient for PR, but scans to document the minimum required response duration of 4 weeks were not obtained before progressive disease occurred. The median progression-free and overall survivals were 2.5 and 7.8 months, respectively. CONCLUSIONS: Although this regimen can be administered safely with appropriate supportive care to patients with good performance status, it has limited therapeutic activity in patients with advanced gastric carcinoma.

Adult↗
PubMed1999

Influence of surface topography on endothelialization of intravascular metallic material.

PURPOSE: To determine whether grooves on a metal surface help endothelialization and, furthermore, what groove size is more likely to promote the fastest endothelialization in an in vitro model. Hypothetically, a microscopic pattern of parallel grooves disposed in the direction of flow, on the inner surface of stents, increases endothelial cell migration rates, resulting in decreased time to total coverage of the prosthetic surface. MATERIALS AND METHODS: Square, flat pieces of nitinol were placed level on a monolayer, confluent culture of endothelial cells. The metal pieces were treated to produce parallel grooves on the surface of 1, 3, 15, and 22 microm to be compared to polished, smooth controls. Microscopy images were obtained by digital capture and processed for analysis of migration distance and cell count, density, shape, and alignment. RESULTS: Grooved surfaces promoted increased rate of migration of endothelial cells, up to 64.6% when compared to smooth, control surfaces. Larger grooves resulted in greater migration rates. The cells aligned with the grooves, elongated, and become more numerous on grooved surfaces, particularly with large grooves. CONCLUSION: A pattern of microscopic parallel grooves more than doubles the migration rate of endothelial cells over metallic surfaces ordinarily used for endovascular stents. Future research in this area is aimed at demonstrating the potential effect of grooved endovascular stent surfaces on faster endothelialization times.

Alloys↗
PubMed1999

Administration of PRN medication: a descriptive study of nursing practice.

In recent years a growing interest has emerged in measuring the outcomes of nursing practice. Although the administration of as required (PRN) medication to psychiatric in-patients is a frequent function performed by psychiatric nurses, nursing literature reveals little research in this important area of practice. As the results of a descriptive study are presented, few psychiatric nursing texts have attempted to address the issues involved.

Adolescent↗
PubMed1998

Corneal light scattering with stromal reformation after laser in situ keratomileusis and photorefractive keratectomy.

OBJECTIVE: To correlate corneal light scattering with keratocyte and extracellular matrix reformation after laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). SETTING: Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, USA. METHODS: Sixteen pigmented rabbit eyes were randomly divided into 2 groups. Group 1 (n = 8) had a 5.0 mm, -10.0 diopter (D) LASIK treatment and Group 2 (n = 8), a 5.0 mm, -10.0 D surface PRK treatment after mechanical epithelial debridement. The stromal surface exposed at surgery was stained with dichlorotriazinylaminofluorescein (DTAF) solution. Slitlamp biomicroscopic and objective measurement of corneal light scattering using a scatterometer were performed 1 and 2 days and 1, 2, 3, 4, 8, and 12 weeks after surgery. In each group, 2 corneas were harvested at 1 week and 1 month and 4 corneas were harvested at 12 weeks. Tissue sections were examined by light and fluorescence microscopy. The percentage of newly formed stromal tissue was calculated and correlated with the scatterometry index. RESULTS: In Group 1, corneas remained clear and healed without significant scarring throughout the study. In Group 2, subepithelial scarring was noted. Extracellular matrix reformation peaked at 1 month and showed a slight regression thereafter. The percentage of extracellular matrix reformation was strongly correlated with the scatterometry index (r = .86, P < .001). CONCLUSIONS: In this study, significant subepithelial stromal tissue reformation followed PRK. The percentage of extracellular matrix reformation correlated well with the objective corneal light scattering measurements.

Animals↗
PubMed1998

Implementing health promoting nursing: the integration of interpersonal skills and health promotion.

Health promoting nursing practice is seen as the way forward for the nursing profession. This paper outlines the meaning of health promotion and distinguishes between a traditional and new paradigm approach. The research examining the extent to which a new paradigm approach is practised demonstrates that, to date, nurses predominantly adopt the traditional approach to health promotion. It is argued that the integration of interpersonal skills and health promotion within nursing curricula is crucial in enabling the transfer of theoretical concepts into practice. The ways in which this integration has been approached within one college of nursing are described. The difficulties encountered in attempting this integration and accomplishing a philosophical shift from a traditional to a new paradigm approach to health promotion are discussed and critiqued. Specifically conflicts that occur at an interpersonal, organizational and societal level are identified and proposed as explanations for the slow implementation of health promoting nursing.

Clinical Competence↗
PubMed1997

Low-level c-myc amplification in human colonic carcinoma cell lines and tumors: a frequent, p53-independent mutation associated with improved outcome in a randomized multi-institutional trial.

Human colonic cancer is associated with multiple genetic deletions, mutations, and alterations in gene expression; in contrast, gene amplification has not been recognized as a prominent characteristic of human colonic tumors. Although the c-myc gene is overexpressed in approximately 70% of human colonic cancers, previous studies have not detected frequent gene amplification or rearrangement of c-myc in these tumors, although such amplification has been reported in chemically induced rodent colon cancer and quantitative analysis of gene copy number has shown the gene to be amplified at a low level in mucinous and poorly differentiated human colon carcinomas. Using rigorously controlled blot methodology, we have established that the c-myc gene, located at 8q21, exhibited amplification of 87% to 35-fold in 7 of 10 human colonic carcinoma cell lines. This was highly significant even at a low level of amplification in HT29 cells (P < 0.0001). Cytogenetic analysis by G-banding did not detect aneuploidy involving chromsome 8q, suggesting that the amplification for the c-myc gene on 8q was relatively specific, and this was consistent with a lack of amplification detected for the c-mos gene on 8q24, which was assayed similarly. The same methodology then revealed amplification of c-myc from 1.5-fold to 5-fold in 32% of tumors from 149 patients entered into a multi-institutional Phase III study of adjuvant therapy for colon cancer. c-myc status was not related to time to recurrence or death, but low levels of c-myc amplification identified a subset of patients who showed a statistically significant increase in disease-free survival, and a corresponding trend to longer overall survival, in response to adjuvant therapy with 5-fluorouracil plus levamisole. Presence of c-myc amplification was not related to incidence of p53 mutations.

Carcinoma↗
PubMed1996

Phase III study of bolus versus infusion fluorouracil with or without cisplatin in advanced colorectal cancer.

BACKGROUND: Phase II studies of fluorouracil (5-FU) administered by protracted intravenous infusion have suggested an improved response rate and decreased toxicity profile when compared with 5-FU given by bolus injection in patients with metastatic colorectal cancer. Additional studies have suggested further enhancement of infusion 5-FU activity when it is combined with low-dose weekly cisplatin administration. PURPOSE: This phase III study in adults with metastatic colorectal cancer was planned as a comparison of objective response rates, toxicity, and survival in patients receiving bolus versus protracted-infusion 5-FU with or without cisplatin. METHODS: Four hundred ninety-seven previously untreated patients with advanced, measurable metastatic colorectal cancer were randomly assigned to receive treatment A (bolus 5-FU at 500 mg/m2 for 5 days followed in 2 weeks by weekly bolus 5-FU at 600 mg/m2), treatment B (bolus 5-FU at 500 mg/m2 for 5 days followed in 2 weeks by weekly bolus 5-FU at 600 mg/m2, plus weekly cisplatin at 20 mg/m2), treatment C (5-FU at 300 mg/m2 per day by continuous infusion), or treatment D (5-FU at 300 mg/m2 per day by continuous infusion plus weekly cisplatin at 20 mg/m2). All drugs were administered intravenously. Enrollment in the trial occurred from August 1987 through December 1990, and follow-up was through September 1995. The Kaplan-Meier method was used to estimate overall and disease-free survival, and Cox regression models were used to assess the effects of patient characteristics on survival. All P values resulted from two-sided tests. RESULTS: Objective tumor response was observed in 28 (18%) of 153 patients receiving treatment A, in 45 (28%) of 159 patients receiving treatment C (C versus A; P = .045), and in 47 (31%) of 153 patients receiving treatment D (D versus A; P = .016). Because of excessive toxicity, treatment B was discontinued after only 12 patients had begun treatment. Median time to disease progression was 5.1 months for patients in arm A compared with 6.2 and 6.5 months for patients in arms C and D, respectively (C versus A, P = .007; D versus A, P = .017). Patterns of toxic effects differed substantially among the treatment arms. Forty-five percent of the patients receiving bolus 5-FU alone (A) experienced grade 3-4 leukopenia, with two sepsis-related deaths. Hand-foot syndrome and mucositis were the major treatment-limiting toxic effects for patients in the two treatment arms involving infusion. Despite the improvement in response rates and time to disease progression with infusion 5-FU with or without cisplatin (C and D, respectively) (P = .003), the overall survival for the three groups (A, C, and D) was similar (P = .307). This may have been due in part to a longer median survival time of 10.4 months for patients in arm A, compared with an anticipated survival of 7 months. CONCLUSION: 5-FU given as a continuous infusion produced a higher objective response rate, a modest prolongation in time to disease progression, and less life-threatening myelosuppression in patients than bolus 5-FU. Concomitant treatment with low-dose cisplatin caused added toxicity and complexity of treatment and did not provide a major clinical benefit. No statistically significant survival differences were observed among the three treatment groups.

Antimetabolites, Antineoplastic↗
PubMed1996

Caring for relatives with serious mental illness: the development of the Experience of Caregiving Inventory.

The aim of this study was to develop a practical, comprehensive, and valid self-report measure of the experience of caring for a relative with a serious mental illness. The notion of caregiver "burden' was rejected; instead caregiving was conceptualised within a 'stress-appraisal-coping' framework. A 66-item version of the Experience of Caregiving Inventory (ECI) was derived from analyses of responses from 626 caregivers, and then tested on an independent sample of 63 relatives of patients with schizophrenia recently in acute care. The extent to which the ECI complied with the stress-coping model was tested, especially the degree to which it, in association with coping, predicted psychological morbidity in carers. Ten sub-scales with good internal consistency resulted from our analyses, eight negative (difficult behaviours; negative symptoms; stigma; problems with services; effects on the family; the need to provide backup; dependency; loss) and two positive (rewarding personal experiences; good aspects of the relationship with the patient). The ECI, in conjunction with coping style, predicted a large proportion of the variance in the General Health Questionnaire (GHQ). We concluded that the ECI taps salient dimensions of caregiving distinct from, although linked with, coping and psychological morbidity. It has potential as a useful outcome measure for interventions aimed at promoting caregiver well-being.

Adaptation, Psychological↗
PubMed1996

A controlled trial of a counselling intervention for caregivers of relatives with schizophrenia.

The effectiveness of short-term interventions to reduce caregiver 'burden' has not been clearly demonstrated. This study assessed the value of six weekly sessions of counselling for key relatives of patients with schizophrenia. The counselling had educational and problem-solving components and was conducted in the family home in the absence of the patient. A randomised controlled design was used. The subjects were the principal caregivers of patients consecutively admitted to acute psychiatric care. Assessments were made pre-treatment and at 3 and 6 months. Of 63 relatives recruited, 47 completed all phases of the study. Relatives in the intervention group reported that they were better able to understand the patient and had a more positive relationship. There were no differences between the intervention and control groups on negative aspects of caregiving or in coping style. Relatives who received the counselling reported slightly greater psychological morbidity at follow-up. However, they all said they would recommend it to others. We concluded that a brief, intensive counselling intervention was of modest benefit to caregivers. Some modifications are suggested.

Adult↗
PubMed1996

The lidgap-Gates (lgGa) mutation for open eyelids at birth maps to mouse chromosome 13.

Complex nonadditive interactions between specific alleles at multiple loci may underlie many so-called multifactorial threshold birth defects. The open-eyelids-at-birth defect in mice is a good model for these defects, and an understanding of its genetic complexity begins with mapping the participating loci. The open-eyelids defect can be part of a syndrome or can occur with no other obvious phenotypic effects. Of the latter nonsyndromic forms, the lidgap series includes four extant mutations that are considered to be alleles based on complementation tests. All show genetic complexity in segregation ratios. None has been mapped previously. On the basis of a strategy of mapping the mutation with the simplest inheritance pattern first, we generated an extensive exclusion map for lidgap-Gates, lgGa, using morphological and protein polymorphisms. We then screened the non-excluded regions in a congenic strain, AEJ.LGG-lgGa, for SSLP markers and located the differential chromosome segment containing the lgGa locus in a region near the distal end of mouse Chromosome (Chr) 13. This linkage was confirmed and refined by typing SSLPs in 64 F2 and 74 BC1 progeny of a cross of LGG/Bc (lgGa/lgGa) to SWV/Bc. The lgGa mutation maps to a 1- to 2-cM region between D13Mit76 and D13Mit53. Integrin alpha 1 and integrin alpha 2, which map to the same general region, are possible candidate loci, based on their embryonic expression and cellular function. Evidence is also presented for a common unlinked recessive suppressor of the open eyelids trait caused by lgGa.

Animals↗
PubMed1996

Corneal topography, ultrasound biomicroscopy, and scatterometry.

This paper presents a review of corneal topography, including history, literature, physics and technology, data analysis, and recent advances in the field. Clinical applications are also discussed and include contact lens fitting, diagnosis of keratoconus, and refractive surgery.

Cornea↗
PubMed1996

Neoadjuvant chemotherapy plus concurrent chemotherapy and high-dose radiation for squamous cell carcinoma of the esophagus: a preliminary analysis of the phase II intergroup trial 0122.

PURPOSE: To determine the preliminary acute toxicity and survival results of neoadjuvant chemotherapy followed by concurrent chemotherapy plus high-dose radiation therapy in patients with local/regional squamous cell carcinoma of the esophagus. MATERIALS AND METHODS: Forty-five patients with clinical stage T1-4N0-1M0 squamous cell carcinoma were entered onto the trial. Eight patients were declared ineligible after registration. Patients received three monthly cycles of fluorouracil (5-FU; 1,000 mg/m2/24hr for 5 days) and cisplatin (100 mg/m2 on day 1) (neoadjuvant segment) followed by two additional monthly cycles of 5-FU (1,000 mg/m2/24hr for 5 days) and cisplatin (75 mg/m2 on day 1) plus concurrent 64.8 Gy (combined modality segment). RESULTS: With a median follow-up of 15 months in surviving patients, the incidence of total grade 3+ toxicity during the neoadjuvant chemotherapy segment was 61%, and during the combined modality segment was 72%. Of the 33 patients who started radiation therapy, 91% were able to complete the full course. There were six deaths during treatment, five of which (11%), because of nadir sepsis and/or dehydration, were treatment-related. For the 37 eligible patients, the median disease-free survival duration was 9 months, and the overall median survival was 20 months. CONCLUSION: The preliminary analysis of this trial demonstrated that the incidence of grade 3+ toxicity was similar to that reported in the combined modality arm of the prior Radiation Therapy Oncology Group (RTOG) intergroup esophageal trial RTOG 85-01. However, because of the increased incidence of treatment-related mortality, this treatment program will not be used as an experimental arm of intergroup trial INT 0123 (RTOG 94-05).

Adult↗