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T Eaton

Publications and source records attributed to T Eaton.

At least 19 recordsLinked to original sources
PubMed2006

Overnight prescription of oxygen in long term oxygen therapy: time to reconsider the guidelines?

BACKGROUND: Guidelines for long term oxygen therapy (LTOT) recommend increasing oxygen flow by 1 l/min overnight. A study was undertaken in patients with COPD on LTOT to determine the prevalence of overnight desaturation if the usual oxygen flow rate is not increased at night, whether resting oxygen saturation predicts overnight desaturation, and whether overnight desaturation correlates with health related quality of life (HRQL) and sleep quality. METHODS: A cross sectional prospective study was performed on consecutive patients with COPD on LTOT attending our regional outpatient oxygen service. All patients fulfilled standard criteria for LTOT, had been established on LTOT at a flow to achieve resting oxygen saturations >90%, but had not been instructed to increase oxygen flow overnight. Overnight desaturation was defined as <90% for > or =30% of the night on either of two consecutive nights. HRQL was evaluated with the SF-36 Health Survey Questionnaire, Chronic Respiratory Questionnaire, and the Pittsburgh Sleep Quality Index. RESULTS: Thirty eight patients (63% men) of mean (SD) age 73.5 (8.04) years and mean (SD) forced expiratory volume in 1 second 0.77 (0.35) l were evaluated. Overnight desaturation occurred in six (16%; 95% CI 4 to 27). Desaturators had mean (SD) resting oxygen saturation on room air of 88 (4.2)% compared with 90 (4.1)% in non-desaturators (p = 0.15), and corrected saturations of 93 (2.0)% versus 94 (2.0)% (p = 0.18). HRQL and sleep quality were poor but did not differ between desaturators and non-desaturators. CONCLUSIONS: Most patients did not exhibit overnight desaturation despite not increasing their LTOT prescription overnight. These results challenge the recommendation of routinely increasing overnight oxygen flow in patients receiving LTOT.

Aged↗
PubMed2006

Short-burst oxygen therapy for COPD patients: a 6-month randomised, controlled study.

Short-burst oxygen therapy (SBOT) remains widely advocated for patients with chronic obstructive pulmonary disease (COPD), despite a lack of supporting evidence. The aim of this randomised, double-blind, placebo-controlled, parallel group study was to determine whether SBOT improves health-related quality of life (HRQL) or reduces acute healthcare utilisation in patients discharged following an acute exacerbation of COPD. Consecutive patients were screened; 78 of 331 were eligible for randomisation to cylinder oxygen, cylinder air or usual care following discharge. Patients were elderly with high acute healthcare utilisation, forced expiratory volume in one second of <1 L and had dyspnoea limiting daily activity but were not hypoxaemic at rest. Over the 6-month study period, there were no significant differences between patient groups in HRQL (Chronic Respiratory Questionnaire (CRQ), 36-item Short-Form Health Survey, Hospital Anxiety and Depression Scale) except for CRQ emotion domain. There were no significant differences in acute healthcare utilisation. Time to readmission was greatest in the usual care group. Cylinder use was high initially, but rapidly fell to very low levels within weeks in both cylinder oxygen and air groups. In conclusion, the availability of short-burst oxygen therapy for chronic obstructive pulmonary disease patients discharged from hospital following an acute exacerbation did not improve health-related quality of life or reduce acute healthcare utilisation. These results provide no support for the widespread use of short-burst oxygen therapy.

Acute Disease↗
PubMed2006

The endurance shuttle walking test: a responsive measure in pulmonary rehabilitation for COPD patients.

BACKGROUND: The endurance shuttle walk test (ESWT) is a standardized externally controlled constant paced field test for the assessment of endurance capacity in chronic lung disease. The ESWT has been advocated as a simple, acceptable, repeatable and responsive outcome measure for COPD patients undergoing pulmonary rehabilitation, but has not been formally compared with the more commonly used field walking test, the six-minute walk (6MW). We aimed to determine: 1) the responsiveness of the ESWT in COPD patients attending a hospital-based pulmonary rehabilitation programme, and 2) to compare the responsiveness of the ESWT with the 6MW. METHODS: Consecutive COPD patients, referred for a standard 8 week pulmonary rehabilitation programme, were recruited. Outcome parameters studied at baseline and completion of rehabilitation programme (8 weeks) included spirometric lung volumes, resting oxygen saturation, breathlessness scored pre and post exercise (modified Borg dyspnoea score), 6MW, ESWT, health-related quality of life (Chronic Respiratory Questionnaire) and Hospital Anxiety and Depression (HAD) scale. The incremental shuttle was employed to predict VO2 peak; 85% VO2 peak was used to determine the walk speed for the ESWT. RESULTS: Twenty stable COPD patients (11 male), mean (SD), age 71, (9) FEV1 0.95 (0.51), resting SpO2 95% (2) 6MW distance (m) 351 (104) and ESWT distance (m) 313 (193) were studied. Three patients did not complete their rehabilitation programme. Following rehabilitation, there were significant improvements in 6MW, ESWT, total CRQ and anxiety domain (HAD). The 6MW distance increased by 17% (47 m 95%CI 3, 90), while the ESWT increased by 92% (302 m 95%CI 104, 501). CONCLUSION: The ESWT is a simple, acceptable and highly responsive outcome measure for COPD patients undergoing a pulmonary rehabilitation programme. The ESWT has potential advantages in that it may be more responsive than the 6MW.

Aged↗
PubMed2005

The Dartmouth COOP Charts: a simple, reliable, valid and responsive quality of life tool for chronic obstructive pulmonary disease.

The negative impact of chronic obstructive pulmonary disease (COPD) on health-related quality of life (HRQL) is substantial. Measurement of HRQL is increasingly advocated in clinical practice; traditional outcome measures such as lung function are poorly responsive. However many HRQL tools are not user-friendly in the clinic setting. Hence HRQL is often neglected. The Dartmouth Cooperative Functional Assessment Charts (COOP) have the requisite attributes of a tool suitable for routine clinical practice: they are simple, reliable, quick and easy to perform and score and well accepted. We aimed to determine the reliability, validity and responsiveness of the COOP in patients with significant COPD. HRQL was assessed during a prospective, randomised, placebo-controlled, double-blind, 12 week cross-over interventional study of ambulatory oxygen in patients (n = 50) with COPD. Test-retest reliability of the COOP domains was only modest however it was measured over a 2 month period. Significant correlations ranging between 0.4 and 0.8 were observed between all comparable domains of the COOP and the Medical Outcomes Study 36-item Short-form Health Survey, Chronic Respiratory Questionnaire (CRQ) and Hospital Anxiety and Depression (HAD) scale. Following ambulatory oxygen significant improvements were noted in all CRQ and HAD domains. Several domains of the generic SF-36 (role emotional, social functioning, role-physical) showed significant improvements. Comparable domains of the COOP (social activities, feelings) also showed significant improvements. The COOP change in health domain improved very significantly. The COOP is a simple, reliable HRQL tool which proved valid and responsive in our study population of COPD patients and may have a valuable role in routine clinical practice.

Activities of Daily Living↗
PubMed2004

Long-term oxygen therapy improves health-related quality of life.

Guidelines for the prescription of long-term oxygen therapy (LTOT) in hypoxemic COPD patients are based on two landmark studies in which survival was the primary outcome. Such patients are importantly symptomatic with poor health-related quality of life (HRQL) but the effect of LTOT on HRQL remains uncertain. We undertook a prospective longitudinal interventional study of consecutive COPD patients referred to our regional oxygen service; n = 43 fulfilling criteria and commenced on LTOT, n = 25 not fulfilling criteria and continued on standard care. HRQL was measured at baseline, 2 and 6 months. Both patient groups had severe COPD as defined by mean FEV1 < 35% predicted. At baseline the LTOT group demonstrated significantly worse HRQL as defined by the Chronic Respiratory Questionnaire (CRQ) (fatigue, emotional function, mastery and total scores), total generic Dartmouth COOP Charts and anxiety domain of the Hospital Anxiety and Depression scale. Significant improvements in HRQL were noted at 2 and 6 months in the LTOT group. Conversely the non-LTOT group demonstrated a progressive decline in HRQL. Using validated criteria for a minimal clinically significant improvement in CRQ, there were 28 (67%) and 26 (68%) 'responders' at 2 and 6 months respectively in the LTOT group. The introduction of LTOT to patients with severe COPD fulfilling standard criteria was associated with early significant improvements in HRQL with sustained or further response at 6 months.

Aged↗
PubMed2002

Management of solitary pulmonary nodules: how do thoracic computed tomography and guided fine needle biopsy influence clinical decisions?

BACKGROUND: Computed tomography (CT) and fine needle guided biopsy (FNB) are often used in the assessment of patients with lung nodules. The influence of these techniques on clinical decision making has not been quantified, especially for small solitary pulmonary nodules (SPN) where the probability of malignancy is lower. A study was undertaken to determine the effect of CT and FNB derived information on clinical decision making in patients with a solitary pulmonary nodule < or = 3 cm in diameter on initial chest radiography. METHODS: Clinical, physiological, and outcome data on 114 patients with an SPN < or = 3 cm who had subsequent thoracic CT and FNB were extracted from the records of a specialist cardiorespiratory hospital in Auckland, New Zealand. Chest radiographs and CT scans were reported according to specified criteria by a thoracic radiologist. Computer generated summary sheets were used to present cases to each of six clinicians. Each case was presented three times: (1) with clinical data and chest radiograph only; (2) with the addition of the CT report; and (3) with all data including the result of the FNB. Clinicians were asked to specify their management on each occasion and to estimate the probability of the lesion being malignant. Reproducibility was assessed by re-evaluating 24 cases 1 month later. RESULTS: 33 (29%) nodules were benign, 35 (31%) nodules (malignant) were resected with negative node sampling, and 46 (40%) had a non-curative outcome (radiotherapy, incomplete resection, refused therapy). Intra-clinician decision making was consistent for all three levels of clinical data (median kappa values 0.79-0.89). Agreement between clinicians on the need for surgery was lowest with chest radiography alone (kappa=0.33), rose with CT information (kappa=0.44), and increased further with the addition of the FNB data (kappa=0.57). The proportion of successful decisions on surgical intervention (against the known outcome) increased with the addition of CT reports and further with FNB reports (p=0.006, Friedman's test). The major benefit of the information added by CT and FNB reports was a reduction in unnecessary surgery, especially when the clinical perception of pre-test probability of malignancy was intermediate (31-70%). FNB data contributed most to the benefit (p<0.001). The addition of CT and FNB was cost efficient and can be applied specifically to patients with a low or intermediate probability of malignancy. CONCLUSION: Both CT and FNB make cost effective contributions to the clinical management of SPN < or = 3 cm in diameter by reducing unnecessary operations and increasing agreement between physicians on the need for surgery.

Adult↗
PubMed2002

Ambulatory oxygen improves quality of life of COPD patients: a randomised controlled study.

It is unknown whether acute response to ambulatory oxygen (O2) predicts longer term improvement in health-related quality of life (HRQL) in chronic obstructive pulmonary disease (COPD) patients. The aims of this study were 1) to assess the short-term clinical impact, as determined by HRQL, of ambulatory O2 in a 12-week, double-blind, randomised crossover study of O2 (versus cylinder compressed air) of dyspnoeic but not chronically hypoxic COPD patients with exertional desaturation < or = 88% (n=41), and 2) to determine whether either baseline characteristics or acute response to O2 predicts short-term (12 weeks) response. Primary outcome measures were Chronic Respiratory Questionnaire (CRQ), Hospital Anxiety and Depression scale and the short form (SF)-36. Improvements were seen in all domains of the CRQ for cylinder O2 compared with cylinder air. Significant improvements were also noted in anxiety and depression and in certain domains of the SF-36. There were 28 (68%) acute responders to cylinder O2 (defined as increase in 6-min walk > or = 54 m or decrease in post-Borg dyspnoea > or = 1) and 23 (56%) short-term responders (defined as clinically significant improvement in CRQ). However, acute and short-term responses were not correlated with no predictors of short-term response identified. At study completion, 14 (41%) of acute or short-term responders did not want to continue therapy, with 11 citing poor acceptability or tolerability. Short-term ambulatory oxygen is associated with significant improvements in health-related quality of life. These benefits cannot be predicted by baseline characteristics or acute response. Despite acute or short-term response, a substantial proportion of patients declined ambulatory oxygen.

Aged↗
PubMed2001

Does visual word identification involve a sub-phonemic level?

The phonological codes activated in visual word recognition can be thought of minimally as strings of discrete and unstructured phoneme-like units. We asked whether these codes might additionally express a letter string's phonological form at a featural or gestural level. Specifically, we asked whether the priming of a word (e.g. sea, film, basic) by a rhyming non-word would depend on the non-word's phonemic-feature similarity to the word. The question was asked within a mask--prime--target--mask sequence with both brief (57 ms in Experiments 1 and 2) and long (486 ms in Experiment 1) prime durations. Non-word primes that differed from their targets by a single phonemic feature (initial voicing as in ZEA, VILM, PASIC) led to faster target lexical decisions than non-word primes that differed by more than a single phonemic feature (e.g. VEA, JILM, SASIC). Visual word recognition seems to involve a sub-phonemic level of processing.

Adolescent↗
PubMed2001

Serious complications with talc slurry pleurodesis.

OBJECTIVE: Talc is a highly efficacious and commonly employed agent for chemical pleurodesis, which has generally been felt to be well tolerated. However, increasing reports of adult respiratory distress syndrome (ARDS) have heightened safety concerns. A recent case of ARDS prompted us to review our experience with talc pleurodesis. METHODOLOGY: We conducted a retrospective review of all patients who received talc slurry pleurodesis at Green Lane Hospital, Auckland, New Zealand, between 1 January 1998 and 31 December 1999 and documented all complications occurring within 48 h of the procedure. RESULTS: Thirty-three talc pleurodesis were performed on 29 patients, most commonly for a malignant pleural effusion. Complications occurred in 15 patients (52% of procedures). Minor complications included tachycardia (n = 11; 33%), pain (n = 9; 27%), fever (n = 8; 24%) and dyspnoea (n = 4; 12%). Major complications occurred in seven patients with hypoxaemia and hypotension. Two of these patients died; one death directly attributable to ARDS, the other hastened by a talc pleurodesis-related tachycardia. CONCLUSIONS: These results challenge the assumption that talc pleurodesis is a safe procedure. There were a significant number of serious complications, including a death, from ARDS. Physicians and patients should be aware that complications occur frequently after talc pleurodesis which may be life-threatening or fatal.

Adult↗
PubMed2001

The clinical utility of arterialized earlobe capillary blood in the assessment of patients for long-term oxygen therapy.

The prescription of long-term oxygen (LTOT) is underpinned by the measurement of arterial PO2, generally obtained by radial artery puncture. This test is commonly associated with patient discomfort and a test that is reliable, well-tolerated and non-invasive would be advantageous. Cutaneous oximetry has not proved sufficiently accurate. Arterialized earlobe capillary sampling has been proposed, with some authors stating that it is under-utilized. However, to date studies have yielded conflicting results and the clinical utility remains uncertain. Our regional oxygen service based at a specialist respiratory hospital undertook a prospective study of consecutive patients with chronic respiratory disease undergoing assessment for LTOT. Simultaneous radial artery and arterialized earlobe sampling was performed. Rigorous steps were taken to ensure optimal arterialization of the earlobe samples. Agreement between arterial and arterialized PO2 and PCO2 was compared using the Bland-Altman method. One hundred patients were studied. Procedural difficulties (insufficient sample or air in sample) were similar for both procedures, however clotting occurred more frequently in arterialized earlobe samples. Sixty-four sample pairs were available for comparison. The bias and limits of agreement between arterialized and arterial PO2 were wide, mean (+/- 2 SD), -048 (-2.05-1.09) kPa. The bias and limits of agreement for PCO2 were smaller. Using the absolute criterion (arterial PO2 < 7.3 kPa), 9/55 (16%) patients would receive oxygen inappropriately based on the arterialized earlobe sample. Conversely, no patients would have been denied LTOT. Radial artery puncture gave rise to significantly greater discomfort (P < 0.0001) and level of concern (P < 0.0001). Patient preference strongly favoured arterialized earlobe sampling. However, despite rigorous attention to arterialization earlobe sampling was insufficiently accurate to replace radial artery puncture in the prescription of LTOT.

Adult↗
PubMed2000

Allergic bronchopulmonary aspergillosis in the asthma clinic. A prospective evaluation of CT in the diagnostic algorithm.

OBJECTIVE: Allergic bronchopulmonary aspergillosis (ABPA) occurs in cases of atopic asthma and may result in important lung disease. Early diagnosis is essential as this disease is responsive to steroids. However, while asthma is common, ABPA is infrequently diagnosed. CT allows precision in the diagnosis of central bronchiectasis (which is virtually pathognomonic of ABPA) and may enable earlier diagnosis. DESIGN: A prospective evaluation of 255 patients with asthma for ABPA, using skin prick testing (SPT) for Aspergillus fumigatus (AF) as a screening tool and incorporating CT into the diagnostic algorithm. SETTING: Asthma clinic, Green Lane Hospital, Auckland, New Zealand. PARTICIPANTS: Patients with asthma. INTERVENTIONS: ABPA was diagnosed using "essential" criteria (ie, asthma, SPT positivity to AF, elevated serum total IgE, elevated serum AF-specific IgE, and pulmonary infiltrates seen on chest radiography or central bronchiectasis seen on CT scan) and "minimal essential" criteria (ie, asthma, SPT positivity, and central bronchiectasis). MEASUREMENTS AND RESULTS: Two hundred fifty-five consecutive patients with asthma who consented to SPT were studied: 218 of 255 patients (86.8%) were atopic; and 47 of 255 patients (21.6%) were AF-positive, of whom 35 accepted further evaluation including CT scanning. A secure diagnosis of ABPA, satisfying all essential criteria, was evident in 9 of 35 patients (25.7%), a proportion that increased to 13 of 35 patients (37.1%) by using the minimal essential diagnostic criteria. CONCLUSIONS: SPT positivity to AF was present in approximately 20% of patients in the asthma clinic. A diagnosis of ABPA is disclosed by CT in 25 to 40% of SPT-positive patients, depending on the selection of diagnostic criteria. These findings support the use of SPT as a screening tool in the asthma clinic and indicate that a routine CT scan is warranted in SPT-positive patients.

Adult↗
PubMed1999

Spirometry in primary care practice: the importance of quality assurance and the impact of spirometry workshops.

OBJECTIVE: To determine the quality of spirometry performed in primary care practice and to assess the impact of formal training. DESIGN: Randomized, controlled prospective interventional study. SETTING: Primary care practice, Auckland City, New Zealand. PARTICIPANTS: Thirty randomly selected primary care practices randomized to "trained" or "usual" groups. One doctor and one practice nurse were nominated to participate from each practice. INTERVENTIONS: "Trained" was defined as participation in an "initial" spirometry workshop at week 0 and a "maintenance of standards" workshop at week 12. "Usual" was defined as no formal training until week 12, when participants they attended the same "initial" workshop provided for the trained group. The study duration was 16 weeks. Each practice was provided with a spirometer to be used at their clinical discretion. MEASUREMENTS AND RESULTS: Spirometry data were uploaded weekly and analyzed using American Thoracic Society (ATS) criteria for acceptability and reproducibility. The workshops were assessed objectively with practical and written assessments, confirming a significant training effect. However, analysis of spirometry performed in clinical practice by the trained practitioners revealed three acceptable blows in only 18.9% of patient tests. In comparison, 5.1% of patient tests performed by the usual practitioners had three acceptable blows (p<0.0001). Only 13.5% of patient tests in the trained group and 3.4% in the usual group (p<0.0001) satisfied full acceptability and reproducibility criteria. However, 33.1% and 12.5% of patient tests in the trained and usual groups, respectively (p<0.0001), achieved at least two acceptable blows, the minimum requirement. Nonacceptability was largely ascribable to failure to satisfy end-of-test criteria; a blow of at least 6 s. Visual inspection of the results of these blows as registered on the spirometer for the presence of a plateau on the volume-time curve suggests that < 15% were acceptable. CONCLUSIONS: Although a significant training effect was demonstrated, the quality of the spirometry performed in clinical practice did not generally satisfy full ATS criteria for acceptability and reproducibility. Further study would be required to determine the clinical impact. However, the ATS guidelines allow for the use of data from unacceptable or nonreproducible maneuvers at the discretion of the interpreter. Since most of the failures were end-of-test related, the FEV1 levels are likely to be valid. Our results serve to emphasize the importance of effective training and quality assurance programs to the provision of successful spirometry in primary care practice.

Adolescent↗
PubMed1998

Comparative clinical and physiological features of Maori, Pacific Islanders and Europeans with sleep related breathing disorders.

UNLABELLED: Recent studies have suggested that there is a familial association of sleep apnoea syndrome and that this is not entirely explained by inheritance of known risk factors. Maori (M) and Pacific Islanders (PI) have many of the body habitus features associated with sleep apnoea and therefore might be expected to exhibit more severe disease than Europeans (E). OBJECTIVE: To compare the clinical and physiological characteristics of the different ethnic groups and to determine if race was an independent predictor of severity of sleep apnoea. METHODOLOGY: A prospective evaluation of patients attending the Sleep Disordered Breathing Clinic which serves the whole of Auckland (population 1.1 million), New Zealand was conducted for the period July 1994 to August 1995. The evaluation included history including a 26 question questionnaire, Epworth sleepiness score, examination, and where indicated, full polysomnography. RESULTS: A total of 233 patients (154 E, 48 M and 33 PI), underwent full polysomnography. Forty-one (85%) of the M and 31 (94%) of PI had obstructive or mixed sleep apnoea compared with only 74 (49%) of the E (P < 0.0001; chi 2). There were few racial differences in the responses to the sleep questionnaire. M and PI were shown to have much greater neck and waist circumference and body mass indices. Severity parameters (apnoea-hypopnoea index, wake and minimum oxygen saturation, and apnoea duration) were greater for both M and PI compared with E (P < 0.001; Mann-Whitney U-test). Stepwise regression identified neck size, body mass index and age as independent predictors of severity. CONCLUSION: When other factors were controlled for, race was not an important independent predictor of severity of sleep apnoea.

Adult↗
PubMed1995

Isolation and characteristics of Mycobacterium avium complex from water and soil samples in Uganda.

SETTING: Mycobacterium avium complex organisms have not been isolated from late stage AIDS patients in Uganda. This could possibly be due to the absence of M. avium complex in the Uganda environment. OBJECTIVE AND DESIGN: Determine whether M. avium complex organisms could be isolated from water and soils collected in the living environment of Ugandan AIDS patients. RESULTS: Representatives of the M avium complex were isolated from 3 of 7 (43%) water and 3 of 7 (43%) soil samples collected in Kampala, Uganda. The average number of colony-forming units per ml water was 3.3 and average colony-forming units per gram of soil was 7825. In terms of growth characteristics, antimicrobial susceptibility patterns, and the presence or absence of plasmids and IS901, Ugandan M. avium complex isolates were similar to those isolated from the US and European AIDS patients and their environment. CONCLUSIONS: M. avium complex organisms sharing genetic and physiological characteristics of M. avium complex isolates recovered from patients with AIDS can be isolated from water and soil samples in Uganda.

Colony Count, Microbial↗
PubMed1995

Recovery of Mycobacterium avium from cigarettes.

Mycobacterium avium was recovered from tobacco, cigarette paper, and cigarette filters. M. avium could also be recovered from cigarette filters after the cigarettes had been smoked.

Mycobacterium avium↗
PubMed1993

Cloning and sequence analysis of the dnaK gene region of Lactococcus lactis subsp. lactis.

A 5.4 kb HindIII fragment of Lactococcus lactis subsp. lactis was identified using a homologous dnaK probe generated by PCR and cloned in Escherichia coli. Upstream sequences were generated by inverse PCR. The two cloned fragments partially overlapped, and sequencing of 5915 bp revealed the presence of four open reading frames in the order orf1-grpE-dnaK-orf4. orf1 encodes a 39 kDa protein of unknown function which shows considerable sequence homology with the Orf39 and Orfa proteins of Bacillus subtilis and Clostridium acetobutylicum, respectively. The downstream ORFs showed high homology to the grpE and dnaK genes of other prokaryotes. The DnaK protein has a characteristic 24-amino-acid deletion exhibited by all the known DnaK proteins of Gram-positive species. In many bacteria the dnaK and dnaJ genes are found as part of the same operon. The L. lactis dnaK operon is unusual in that the dnaK gene is followed by a putative transcription terminator and a fourth large ORF which shares no homology with the dnaJ genes of other bacteria but has a small degree of homology with various membrane proteins. Vegetative promoter sequences are found upstream of both orf1 and orf4. A 12 bp inverted repeat is found upstream of the putative promoter of orf1 and an 8 bp inverted repeat is found between this promoter and the orf1 initiation codon. These repeats are thought to be involved in regulation of the heat-shock genes. The DnaK homologue is induced approximately 3-fold on heat shock at 42 degrees C.

Amino Acid Sequence↗
PubMed1993

Isolation of Mycobacterium avium complex from water in the United States, Finland, Zaire, and Kenya.

Disseminated infection with organisms of the Mycobacterium avium complex (MAC) is a common complication of AIDS in the United States and other developing countries, but it is rare or absent in sub-Saharan Africa. To assess the comparative likelihood of exposure to MAC in these geographic areas, we used a standard protocol to culture 91 water samples from environmental sites and piped water supply systems in the United States, Finland, Zaire, and Kenya. MAC was isolated from all geographic areas and from 22 of 91 (24%) samples. Isolation rates were 13 of 47 (28%) for environmental samples and 9 of 44 (20%) for water supply samples. Overall isolation rates were 18 of 52 (35%) samples in the United States and Finland, whereas they were 4 of 39 (10%) samples in Zaire and Kenya (P = 0.015). MAC isolation rates from water supply systems were 8 of 25 (32%) samples in the United States and Finland and 1 of 19 (5%) samples in Zaire and Kenya (P = 0.056). MAC was isolated from hospital water in the United States and Finland but not in hospital water in Zaire and Kenya. Serovar determinations showed that six of eight isolates from the United States were serovar 4 or 8. One MAC isolate from Zaire was identified as an "X" mycobacterium. These data suggest that exposure to MAC in water is likely in diverse areas of the world, but that the likelihood of human exposure to the organism in water may be slightly less in sub-Saharan Africa than in developed countries in the Northern Hemisphere.

AIDS-Related Opportunistic Infections↗