Analysis of denitrification by Pseudomonas stutzeri under nutrient-limited conditions using membrane inlet mass spectrometry

Membrane inlet mass spectrometry (MIMS) was used to investigate denitrification by Pseudomonas stutzeri in a static lake water column. Continuous real-time measurement of gases enabled the dynamics of the process to be investigated. Concentrations of 17 mmol l-1 nitrate and 10 mmol l-1 nitrite were identified as optimal for denitrification under nutrient-limited conditions (i.e., produced the highest concentrations of N2). Available carbon was the major rate-limiting factor in lake water when nitrate or nitrite was present. No stratification of the process with depth was observed, and aerobic denitrification was apparent under all the conditions employed. The rate of denitrification was dependent on cell concentration, and possible limitations of the usefulness of MIMS under environmentally modelled conditions were identified for environments containing low numbers of bacteria.

HBME-1, MOC-31, WT1 and calretinin: an assessment of recently described markers for mesothelioma and adenocarcinoma

AIMS

To evaluate HBME-1, WT1, calretinin and MOC-31 in the differential diagnosis of pleural mesothelioma and adenocarcinoma of the lung.

METHODS AND RESULTS

Paraffin-embedded formalin-fixed blocks from six reactive pleuras, 42 mesotheliomas and 40 adenocarcinomas were used. Sections were stained for Leu-M1, HBME-1, calretinin, WT1 and MOC-31. Leu-M1 was positive or equivocal in 34% of mesotheliomas and in 78% of adenocarcinomas; reactive pleuras were all negative. HBME-1 was positive or equivocal in 76% of mesotheliomas and in 73% of adenocarcinomas; five reactive pleuras were positive. Calretinin was positive or equivocal in 92% of mesotheliomas and in 73% of adenocarcinomas; two reactive pleura were equivocal and four were positive. WT1 was positive or equivocal in 72% of mesotheliomas (excluding autopsy cases) and in 20% of adenocarcinomas; all reactive pleuras were positive. MOC-31 was positive or equivocal in 5% of mesotheliomas and in 90% of adenocarcinomas; all reactive pleuras were negative. The reaction with Leu-M1 was graded as equivocal in 25% of the adenocarcinomas. All 24 of the autopsy cases of mesothelioma were negative for WT1 and in many operative specimens only the periphery was stained.

CONCLUSIONS

Neither calretinin nor HBME-1 are sufficiently discriminatory to be of use, even as members of a panel of antibodies. WT1 shows some promise, but it cannot be used on autopsy material. The utility of MOC-31 is confirmed, and outperforms Leu-M1.

Functional brain imaging of movement disorders

Functional brain imaging techniques such as positron emission tomography (PET) have contributed to our understanding of the pathophysiology of Parkinson's disease (PD) and other movement disorders. PET employs small amounts of positron emitting radioligands to produce quantitative measures of physiological and biochemical processes in the brain and other organs. In a PET experiment, a subject is given a compound of biological interest. The spatial and temporal distribution of the radiotracer is measured quantitatively in the course of the PET study, providing a tomographic representation of regional radioactivity concentration. In this review, we focus on the potential application of PET in the selection of suitable candidates and the assessment of surgical interventions such as pallidotomy, thalamotomy, and deep brain stimulation.

Patients with t(8;21)(q22;q22) and acute myeloid leukemia have superior failure-free and overall survival when repetitive cycles of high-dose cytarabine are administered

PURPOSE

To examine the effect of single compared with repetitive (at least three) cycles of high-dose cytarabine after induction therapy for patients with acute myeloid leukemia (AML) who have the t(8;21)(q22;q22) karyotype.

PATIENTS AND METHODS

Patients entered onto the study had AML and t(8;21) and attained a complete remission on four successive Cancer and Leukemia Group B studies. In these studies, either > or = three cycles of high-dose cytarabine or one cycle of high-dose cytarabine was administered, followed by sequential cyclophosphamide/etoposide and mitoxantrone/diaziquone with or without filgrastim support. Outcomes of these two groups of t(8;21) patients were compared.

RESULTS

A total of 50 patients with centrally reviewed AML and t(8;21) were assigned to receive one (n = 29) or > or = three cycles (n = 21) of high-dose cytarabine as postinduction therapy. The clinical features of these two groups of patients were similar. Initial remission duration for t(8;21) patients assigned to one cycle of high-dose cytarabine was significantly inferior (P =.03), with 62% of patients experiencing relapse with a median failure-free survival of 10.5 months, compared with the group of patients who received > or = three cycles, in which only 19% experienced relapse and failure-free survival is estimated to be greater than 35 months. Furthermore, overall survival was also significantly compromised (P =.04) in patients assigned to one cycle of high-dose cytarabine, with 59% having died as a consequence of AML, compared with 24% of those who received > or = three cycles of high-dose cytarabine.

CONCLUSION

These data demonstrate that failure-free survival and overall survival of patients with t(8;21)(q22;q22) may be compromised by treatment approaches that do not include sequential high-dose cytarabine therapy.

'Something always comes up': nurse-patient interaction in an acute psychiatric setting

In this study, 10 nurses and 10 patients were interviewed to explore factors influencing nurse-patient interactions in an acute psychiatric inpatient facility. The six themes that emerged from the nursing interviews were; environment, something always comes up, nurses' attributes, patient factors, instrumental support and focus of nursing. The four themes from the patient interviews were; nurses' attributes, role perceptions, clinical care, and time. These findings have implications for clinical practice, the nurses' role and nursing education.

REM sleep in depression is influenced by ethnicity

The influence of ethnicity on the manifestation of EEG sleep changes in depression was studied in 95 patients (21 African-Americans [AA], 17 Asians [AS], 37 Caucasians [C] and 20 Hispanics [H]) with unipolar major depression. Subjects were studied twice for 2 consecutive nights. On the second night of each 2-night session, placebo or scopolamine (1.5 microg/kg, IM, at 23.00 h) was administered. On the baseline (placebo) night, sleep architecture, sleep continuity and rapid eye movement (REM) sleep variables were generally comparable among the groups. However, REM sleep was less in AA and AS subjects than in C and H subjects. Furthermore, the distribution of REM sleep over the course of the night in AA and AS subjects differed significantly from that in the C and H groups. Although scopolamine significantly affected sleep continuity and REM sleep measures, no significant differential effects of scopolamine were observed. Because many antidepressants suppress REM sleep, the differences in baseline REM sleep observed might be related to the greater sensitivity of some ethnic-minority depressed patients to pharmacotherapy.

Molecular Ecological Analysis of Methanogens and Methanotrophs in Blanket Bog Peat

Abstract Methane production and methane oxidation potential were measured in a 30 cm peat core from the Moorhouse Nature Reserve, UK. The distribution of known groups of methanogens and methane oxidizing bacteria throughout this peat core was assessed. Using 16S rRNA gene retrieval and functional gene probing with genes encoding key proteins in methane oxidation and methanogenesis, several major groups of microorganisms were detected. Methane production and oxidation was detected in all depths of the peat core. PCR amplification and oligonucleotide probing experiments using DNA isolated from all sections of the peat core detected methanotrophs from the groups Methylosinus and Methylococcus and methanogens from the groups Methanosarcinaceae, Methanococcaceae, and Methanobacteriaceae. 16S rDNA sequences amplified with the Methylosinus-specific primer were shown to have a high degree of identity with 16S rDNA sequences previously detected in acidic environments. However, no methanogen sequences were detected by the probes available in this study in the sections of the peat core (above 7 cm) where the majority of methanogenesis occurred, either because of low methanogen numbers or because of the presence of novel methanogen sequences.http://link.springer-ny.com/link/service/journals/00248/bibs/38n3p225.html</hea

Effects of cultural conditions on denitrification by pseudomonas stutzeri measured by membrane inlet mass spectrometry

Denitrification is a globally important process leading to loss of fertiliser efficiency and the production of the greenhouse gas nitrous oxide and nitric oxide, an ozone depleter. Membrane inlet mass spectrometry (MIMS) was employed to study the effect of different variables on the process of denitrification by Pseudomonas stutzeri in a defined salts medium. MIMS was used for concomitant measurements of nitrous oxide, nitrogen and oxygen and showed that denitrification occurred in the presence of dissolved oxygen. A nitrate concentration of 15 mmol l-1 and a nitrite concentration of 5 mmol l-1 were found to be optimum for complete denitrification of nitrate or nitrite to nitrogen and varying these concentrations had a marked effect on the ratio of gaseous products released. Denitrification products were also dependant on pH with neutral or alkaline conditions being best for production of gaseous end products. Our results suggest that under nutrient rich conditions the most important factor in the regulation of denitrification by Ps. stutzeri is the amount of nitrite generated at the first enzymatic stage of the process. This appears to cause inhibition of the denitrification pathway above 5 mmol l-1 and at high enough concentrations (15 mmol l-1) restricts growth.

Factors influencing nurse-patient interaction in the acute psychiatric setting: an exploratory investigation

Nurse-patient interaction in acute psychiatric in-patient facilities has been the subject of much discussion in the literature and remains a contentious issue. How and why nurses interact with patients in the acute care setting requires definition within the current dynamic environment of mental health service provision. Factors which impact on the manner in which nurses care for patients also require investigation. This article presents the findings of a collaborative research study that investigates factors that influence nurse-patient interaction in the acute psychiatric setting. Ten nurses on the study ward were given opportunity, through semi-structured interviews, to outline and describe the factors perceived to influence nurse-patient interaction. Factors identified as influencing interaction included the ward environment, something always comes up, nurses' attributes, patient factors, instrumental support and focus of nursing. Issues which emerged from the study provide managers and clinical nurses with an opportunity for generating new possibilities for nurse-patient interaction. However, these issues must be addressed in a sensitive way that takes into account the complex and dynamic nature of acute care settings.

Soluble tumor necrosis factor receptor prevents post-pump syndrome

Post-pump syndrome is an acute lung injury following cardiopulmonary bypass (CPB) which is indistinguishable from the adult respiratory distress syndrome (ARDS). Tumor necrosis factor (TNF) is central to the inflammatory process and is capable of triggering the entire pathophysiologic response leading to ARDS. We hypothesized that treatment with a soluble TNF receptor-binding protein (TNFbp) would reduce the increase in serum TNF and prevent acute lung injury in our sequential insult model of ARDS following CPB. Anesthetized pigs were randomized to one of three groups: Control (n = 3), surgical preparation only; CPB + LPS (n = 6), femoral-femoral hypothermic bypass for 1 h followed by infusion of low dose Escherichia coli lipopolysaccharide (LPS; 1 microg/kg); and TNFbp + CPB + LPS (n = 4), pretreatment with intravenous TNFbp (2 mg/kg) followed immediately by both insults. CPB + LPS caused severe lung injury demonstrated by a significant fall in PaO2 and an increase in both intrapulmonary shunt and peak airway pressure as compared to all groups (P < 0.05). These changes were associated with a significant increase in plasma TNF level and pulmonary neutrophil sequestration. TNFbp significantly reduced plasma levels of TNF and prevented the lung injury typically observed with this ARDS model, but did not reduce pulmonary neutrophil sequestration. Thus, elevated serum TNF is not responsible for neutrophil sequestration but does play a role in neutrophil activation which causes lung injury. Prophylactic use of TNFbp in CPB patients may prevent neutrophil activation and reduce the incidence of post-pump ARDS.

Success habits of long-term gastric bypass patients

BACKGROUND

By identifying common habits of the most successful long-term gastric bypass patients, one is able to establish more specific guidelines for new patients to follow. The first postoperative year is a critical time that must be dedicated to changing old behavior and forming new, lifelong habits.

METHODS

100 gastric bypass patients from 1979 to 1995 participated in a comprehensive survey. Surveys were completed in person, by phone, or in writing. Participants were asked to answer questions regarding their eating, drinking, sleeping, exercise, and personal habits.

RESULTS

The survey revealed that specific habits are common in gastric bypass patients who have maintained their weight loss for many years.

CONCLUSION

Identifying and defining the common habits of patients who are successful with long-term weight loss enabled specific guidelines to be established for new patients to implement during the initial weight loss phase, which will contribute to life-long success.

Effect of subcutaneous granulocyte colony-stimulating factor injectate volume on drug efficacy, site complications, and client comfort

PURPOSE/OBJECTIVES

To determine the effect of administering 1.6 ml (480 mcg) of granulocyte colony-stimulating factor (G-CSF) in one subcutaneous injection or two injections of 0.8 ml each.

DESIGN

Experimental.

SETTING

27-bed bone marrow transplant intensive care unit of a metropolitan, university medical center in the southwestern United States.

SAMPLE

Nonprobability; 76 women who received high-dose chemotherapy for breast cancer followed by hemopoietic rescue.

METHODS

Subjects were randomized into an experimental group that received one injection per 480 mcg dose and a control group that received two injections per 480 mcg dose administered by research associates using a standardized injection technique.

MAIN RESEARCH VARIABLES

Injectate volume. The number of days post-transplant until the absolute neutrophil count (ANC) returned to 1,000/mm3, the incidence and surface area in mm2 of site complications, and scores on Tursky's Quantified Pain Descriptor immediately following the injection(s).

FINDINGS

No significant difference existed between the two groups in ANC recovery time, frequency or size of site complications, or intensity, reaction, or sensation of discomfort reported.

CONCLUSIONS

Administering 1.6 ml doses of G-CSF in one injection instead of two does not result in slower ANC recovery, induration, more frequent or larger bruises or areas of erythema, or greater client discomfort.

IMPLICATIONS FOR NURSING PRACTICE

Administering one injection instead of two may decrease patients' anxiety, the nursing time needed for preparation and administration of injections, patient instruction for self-administration, the potential for contamination of vials or loss of dose, and the cost of supplies.

Age-based rationing of medical care in nineteenth-century England

This article questions whether indoor medical care for the elderly provided under the poor law and by voluntary hospitals during the second and third quarters of the nineteenth century was rationed on the basis of age and, given that the elderly were discriminated against compared with other age groups, how their ability to secure medical care changed over time and between providers.

The research was motivated by the current debate on the allocation of scarce health care resources in the British National Health Service. This debate has contrasted the traditional approach of doctors who ration care on the basis of medical need, that is through clinical assessment of a patient's state of health, with new solutions developed by health economists and medical ethicists who seek to maximize the health care outputs society can buy or the welfare individuals can achieve over their lifetime.

I use admission and discharge registers from two case studies – a voluntary hospital in Bristol and a workhouse infirmary in East London – to test the following hypothesis: that during the period medical resources, as defined by admissions and hospital days, were allocated according to the medical need of age groups. Differential access to medical and nursing staff, to remedies or interventions, and standards of hygiene or diet are not considered. Although these care components were clearly important, and some aggregate indicators may be calculated for the two providers, the available sources do not allow comparison of the allocation of these components between age groups.

Section II outlines the theoretical framework underpinning this article and Section III introduces the historical context. The sources of data are described in Section IV and the evidence is presented in Section V. The final section contributes to the historiography of old age for nineteenth-century England by suggesting ways in which to interpret the findings.

The Maudsley Addiction Profile (MAP): a brief instrument for assessing treatment outcome

AIM

To develop a brief, multi-dimensional instrument for assessing treatment outcome for people with drug and/or alcohol problems. The Maudsley Addiction Profile (MAP) is the first instrument to be developed in the United Kingdom for this purpose.

DESIGN

Field testing with quota-recruitment of problem drug users and problem alcohol users in treatment with researcher and clinician-administered test-retest interviews.

SETTING

Two community and two inpatient services at the Bethlem Royal and Maudsley Hospital, London.

PARTICIPANTS

Subjects (160 drug users and 80 alcohol users) interviewed by eight interviews (four researchers and four clinicians), each of whom interviewed 30 subjects on two occasions.

MEASURES

Sixty items across substance use, health risk, physical/psychological health and personal/social functioning domains.

FINDINGS

Average completion time of the MAP was 12 minutes. The questionnaire was acceptable to a majority of subjects and performed well with both researcher and clinician interviewers. Internal reliability and feasible concurrent validity assessments of the scales and items were highly satisfactory. Test-retest reliability was good, average intraclass correlation coefficients across eight substances were 0.94 and 0.81 across health risk, health problems, relationship conflict, employment and crime measures.

CONCLUSIONS

The MAP can serve as a core research instrument with additional outcome measures added as required. The collection of a set of reliable quantitative measures of problems among drug and alcohol users by research or treatment personnel for outcome evaluation purposes need not be time-consuming.

Substance use, health and social problems of service users at 54 drug treatment agencies. Intake data from the National Treatment Outcome Research Study

BACKGROUND

The National Treatment Outcome Research Study (NTORS) is the first large-scale, prospective, multi-site treatment outcome study of drug users in the UK.

METHOD

Substance use, health and social problems of 1075 service users were assessed at intake to 54 agencies chosen to be representative of the main national drug treatment modalities.

RESULTS

Heroin dependence was the most frequently reported problem often with poly-drug and alcohol problems. Most service users injected drugs and a quarter of the injectors shared injecting equipment. Poly-drug use and heavy drinking were more common among service users admitted to residential treatments. High criminality rates were reported. Psychological and physical health problems were common and many service users had prior contact with psychiatric and medical services.

CONCLUSIONS

The range and severity of problems adversely affect individual users, their families, and present a challenge to addiction treatment services. These problems create costs for the health care, social service and criminal justice system responses.

Clinicopathologic analysis of mullerian adenosarcoma: the M.D. Anderson Cancer Center experience

The records of 41 patients diagnosed with adenosarcoma of the female genital tract between 1982 and 1996 were reviewed. The median age at diagnosis is 51 years (range, 14-84). The most common symptom is vaginal bleeding (71%). Clinical signs at presentation include pelvic mass (37%), uterine polyps (29%), and enlarged uterus (22%). In 71% of patients, the tumor originates from the uterus. Other sites include ovary (15%), pelvis (12%), cervix (2%). A history of thyroid cancer, benign ovarian cyst, and polycystic ovarian disease is found more frequently than expected in this patient population, whereas no relationship to endometriosis is observed. Surgery is the mainstay of treatment, but platin-based chemotherapy given upfront in inoperable patient has definite efficacy. An overall response rate of 92.5% was observed after primary therapy (surgery with or without radiotherapy, and/or chemotherapy), with a median survival of 48 months (range, 1-174). Thirty-eight percent of patients had recurrent disease. The median time to recurrence is 12 months (range, 5-132). Although 60% of patients with recurrence achieved a complete remission after treatment, only 1 (8%) is alive without disease, and 3 (22%), with disease at the time of this analysis. In our series, histologic sarcomatous overgrowth is a predictor of poor prognosis (p<0.03), however myometrial invasion and stage of disease seem to be of less prognostic significance. Adenosarcoma is a tumor with a fair prognosis. Most tumor can be cured with surgery, but recurrence carries a bad prognosis.

Diffusible, nonfibrillar ligands derived from Abeta1-42 are potent central nervous system neurotoxins

Abeta1-42 is a self-associating peptide whose neurotoxic derivatives are thought to play a role in Alzheimer's pathogenesis. Neurotoxicity of amyloid beta protein (Abeta) has been attributed to its fibrillar forms, but experiments presented here characterize neurotoxins that assemble when fibril formation is inhibited. These neurotoxins comprise small diffusible Abeta oligomers (referred to as ADDLs, for Abeta-derived diffusible ligands), which were found to kill mature neurons in organotypic central nervous system cultures at nanomolar concentrations. At cell surfaces, ADDLs bound to trypsin-sensitive sites and surface-derived tryptic peptides blocked binding and afforded neuroprotection. Germ-line knockout of Fyn, a protein tyrosine kinase linked to apoptosis and elevated in Alzheimer's disease, also was neuroprotective. Remarkably, neurological dysfunction evoked by ADDLs occurred well in advance of cellular degeneration. Without lag, and despite retention of evoked action potentials, ADDLs inhibited hippocampal long-term potentiation, indicating an immediate impact on signal transduction. We hypothesize that impaired synaptic plasticity and associated memory dysfunction during early stage Alzheimer's disease and severe cellular degeneration and dementia during end stage could be caused by the biphasic impact of Abeta-derived diffusible ligands acting upon particular neural signal transduction pathways.