Low genetic diversity of Banana bunchy top virus, with a sub-regional pattern of variation, in Democratic Republic of Congo.

Banana bunchy top virus (BBTV), belonging to the genus Babuvirus, is the most devastating and widespread banana virus. Banana and plantain are major crops in terms of household income and food security in Democratic Republic of Congo (DRC). Despite the large area under banana and plantain cultivation in the country, before this study, the genetic characterization of BBTV isolates had only been undertaken for two provinces. In the study presented here, genetic variation in BBTV was assessed from 52 BBTV isolates collected in five out of 11 provinces in DRC (Bandundu, Bas-Congo, Katanga, Kinshasa and Kasaï Oriental) and in two provinces using sequences previously described in databases. Full genome sequencing of DNA-R components was performed, revealing low genetic variation (98-100 % nucleotide identity) among the BBTV isolates detected. The phylogenetic analyses showed that all the DRC isolates were clustered in the South Pacific clade of BBTV. Based on the coding region for the replication initiator protein, haplotype diversity was estimated to be 0.944 ± 0.013, with 30 haplotypes from 68 isolates in DRC. Such diversity shows a haplotype distribution mainly at the sub-regional level in DRC. In addition, the sequence determination from the whole genome of selected isolates confirmed low genetic variation among isolates from seven DRC provinces (97-100 % nucleotide identity). This study strengthened the hypothesis of a single BBTV introduction some time ago, followed by the spread of the virus in the country.

Aortic coarctation - never too late to diagnose, never too late to treat.

We present two cases of severe aortic coarctation detected in adulthood and who underwent successful relief by transcatheter stent deployment using a new covered stent, Optimus® stent (AndraTec GmbH Koblenz, Germany). One patient is a 46-year old female with resistant arterial hypertension, in whom coarctation was suspected on a follow-up transthoracic echocardiogram for bicuspid aortic valve disease and subsequently confirmed on magnetic resonance imaging. The second patient is a 68-year old male whose coarctation was diagnosed incidentally at coronary angiography being performed as part of the preoperative work-up for severe aortic stenosis. Suprasternal views to assess aortic arch and flows in the proximal descending aorta should be a standard part of every transthoracic echocardiogram. Treatment of aortic coarctation should be considered irrespective of patient's age.

Once- and twice-daily bevantolol for systemic hypertension using 24-hour ambulatory intraarterial blood pressure recording.

The antihypertensive efficacy of bevantolol, a selective beta 1-adrenoreceptor antagonist, was evaluated in 17 patients with essential hypertension, using continuous ambulatory intraarterial blood pressure (BP) monitoring. The study compared a twice-daily regimen (titrated dose of 200 to 600 mg/day) with the same amount given in a single daily dose. Within-patient comparisons of mean hourly systolic and diastolic BPs and heart rate showed a highly significant effect with twice-daily therapy (p less than 0.001) for all of the 24 hours. Similar significant results were obtained with a single morning dose. There was no difference between the pattern or extent of BP reduction with the 2 regimens. The decrease in BP after bevantolol persisted during the physiologic tests (rest, tilt, isometric and dynamic exercise). Four patients developed minor side effects with the single morning dose, and only 1 patient with the twice-daily regimen. These effects included tiredness, fatigue and dizziness. Unlike pure beta-blocking agents, bevantolol controlled the early morning increase in BP, lending support to the belief that it possesses vasodilatory properties in addition to beta blockade. These results suggest that bevantolol may be useful as first-line therapy in a once-daily dosage for the treatment of essential hypertension.

Carvedilol for systemic hypertension.

Twenty-four-hour profiles of intraarterial ambulatory blood pressure (BP) and heart rate were significantly reduced by administration of carvedilol, a new beta-blocking drug with vasodilating properties. Twelve patients were given carvedilol, 25 mg twice daily for 2 weeks; the dose was then increased to 50 mg twice daily if the target BP was not achieved. After 4 weeks of therapy, mean daytime reduction in BP was 25 +/- 3 mm Hg systolic and 19 +/- 3 mm Hg diastolic and mean reduction in heart rate was 22 +/- 3 beats/min. BP at the peak of isometric exercise and during dynamic exercise was also significantly reduced. Radionuclide measurements showed that left ventricular ejection fraction was not affected by treatment, but there was a significant reduction in systolic and diastolic volumes. The drug was well tolerated. This clinical trial suggests that carvedilol will be a useful first-line drug for treatment of essential hypertension, and its vasodilating action may have a more favorable effect on left ventricular function than conventional beta-blocking drugs.

Effects of chronic congestive heart failure secondary to coronary artery disease on the circadian rhythm of blood pressure and heart rate.

In 20 subjects with chronic congestive heart failure due to coronary artery disease, the 24-hour variability of ambulatory intraarterial blood pressure (BP) was studied using an improved Oxford Medilog system, and correlated with left ventricular function at rest. The mean radionuclide ejection fraction was 27% (range 10 to 42), the mean pulmonary arterial wedge pressure was 18 mm Hg (5 to 37) and the mean cardiac index was 2.8 liters/min/m2 (2 to 3.8). The 24-hour systolic BP and heart rate (HR) variability indexes were less than those of 22 normal volunteers (p less than 0.05) and were strongly correlated (p less than 0.05) with ejection fraction at rest and pulmonary arterial wedge pressure. Stepwise regression showed that a combination of the mean nocturnal HR and the standard deviation of the hourly mean systolic BP values accounted for 67% of the variability in ejection fraction between patients. Similarly, 73% of the variation in pulmonary wedge pressure was explained by combining the 24-hour mean HR and the mean nocturnal HR.

First dose response and 24-hour antihypertensive efficacy of the new once-daily angiotensin converting enzyme inhibitor, ramipril.

The reduction in blood pressure (BP) after the first dose and after 8 weeks of treatment with a new once-daily angiotensin converting enzyme (ACE) inhibitor, ramipril, was examined in 12 untreated hypertensive patients, using ambulatory intraarterial BP monitoring. The first period of monitoring began 24 hours before the first dose was given, and continued for 24 hours afterwards. A second 24-hour period of monitoring was carried out after 8 weeks of treatment, commencing immediately after the morning dose. Angiotensin II levels and serum drug levels were measured at 0, 2, 6 and 24 hours after the acute dose. BP decreased progressively from the first hour after the first dose, reached a maximum in the fifth hour (p less than 0.001) and then the effect diminished. The maximum reduction of systolic BP in any patient was 64 mm Hg, the minimum 4 mm Hg. Blood pressure was significantly (p less than 0.05) reduced throughout the 24 hours after dosing, with a mean daytime reduction of 13/12 mm Hg, and a mean nighttime reduction of 15/7 mm Hg. Angiotensin II levels were significantly (p less than 0.02) and maximally reduced by 2 hours after administration, but the reduction was no longer significant after 24 hours. Serum drug levels were also maximal 2 hours after administration. The trial population could be clearly divided into groups of good and poor responders on the basis of BP reduction. The angiotensin II levels were higher before treatment, and decreased further, in all patients with a good response than in those with a poor response.(ABSTRACT TRUNCATED AT 250 WORDS)

A comprehensive clinical validation of the nuclear stethoscope.

Five studies were conducted to examine the degree of variability to be expected during the use of the non-imaging nuclear probe (BIOS Inc.) under a variety of clinical conditions. Comparison of the ejection fraction (EF) readings between the nuclear probe and a gamma camera showed good agreement, with the nuclear probe tending to underestimate lower, and overestimate higher camera EF values [mean (S.D.) difference, 0.84% (6.06)]. A comparison of two nuclear probes showed a small mean (S.D.) difference of EF readings of 0.063% (2.26). EF readings obtained in normal subjects 6 weeks apart were reproducible and differed by a mean (S.D.) of 0.23% (4.42). The administration of placebo to 10 normal subjects followed by sequential measurements for 4 h produced EF changes large enough to mimic a clinical effect, the largest hourly change observed being 5.4%, indicating the need for strict placebo control in interventional experiments. Data on four patients with heart failure showed small non-significant EF changes in the 1 h after placebo administration but a wide intra-subject range of ejection time and time to peak filling measurements. This highlights the problem of accurate, reproducible cursor placement in such patients. The nuclear probe is a portable, low cost instrument which produces accurate EF measurements when compared with the gamma camera.

Acute and chronic effects of nicardipine on systolic and diastolic left ventricular performance in patients with heart failure: a pilot study.

Nicardipine is a new calcium ion antagonist with vasodilating properties which has been shown to be effective in the treatment of hypertension and angina. We have studied its effect on systolic and diastolic left ventricular function in patients with mild to moderate degrees of congestive heart failure. Ten male patients with New York Heart Association Class II and III heart failure underwent acute treatment with an intravenous infusion of nicardipine (10 mg over 10 minutes). A nuclear probe was used to monitor left ventricular ejection fraction, peak filling rate, and relative cardiac output. Blood pressure and heart rate were also measured. The blood pressure (mean +/- SD) fell from 133 +/- 26/86 +/- 11 mmHg to 103 +/- 22/69 +/- 13; the heart rate rose from 67 +/- 9 beats/min to 85 +/- 10; left ventricular ejection fraction from 31 +/- 7 to 38 +/- 6%; relative cardiac output from 24 +/- 9 to 41 +/- 11; peak filling rate from 1.18 +/- 0.4 end-diastolic volume per second to 1.82 +/- 0.4 (p less than 0.001 in all cases) at the end of infusion. After 4 weeks of chronic treatment in eight patients (20 mg to be taken three times daily (tds) in one and 40 mg tds in 7), the blood pressure and heart rate had returned to baseline values but the improvements in left ventricular ejection fraction, relative cardiac output, and peak filling rate were sustained; this was associated with functional improvement in all 8 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Nature, Incidence, and Symptomatology of Viruses Infecting Vanilla tahitensis in French Polynesia.

A survey was carried out to identify the viruses infecting vanilla in French Polynesia and to assess their incidence. Virus identification was based on enzyme-linked immunosorbent assay (ELISA) and, for potyviruses, on the sequence of part of the coat protein and inoculation assays. Between 1998 and 1999, 3,610 vanilla plants from 49 plots in the Society Islands were indexed. Cymbidium mosaic virus (CymMV) was detected in 500 vines from 10 plots in the Leeward Islands. The data suggest that this virus has spread widely since its first detection in French Polynesia in 1986, most likely through the dissemination of symptomless infected cuttings. Viruses belonging to the Potyvirus genus were found in 674 plants from 27 plots in the four islands surveyed. Three distinct potyviruses have been identified: (i) Vanilla mosaic virus, (ii) Watermelon mosaic virus, and (iii) and a virus related to Bean common mosaic virus. The symptoms induced on Vanilla tahitensis by the three potyviruses can be differentiated from each other and from those due to CymMV. A significant proportion of the plants surveyed (97/476) were symptomatic but tested negative by ELISA for CymMV and the Potyvirus group. Odontoglossum ringspot virus was not detected in any sample tested.

Intrahospital transport of the critically ill adult: a research review and implications.

Transporting the critically ill adult from the relative stability of the critical care environment to a testing site or new area is a nursing responsibility. Yet current research about the risks and benefits of intrahospital transport is at times conflicting. This article provides an analysis of available research on the critical elements involved in intrahospital transport and suggests recommendations for clinical practice.

Male breast cancer: report of 2 cases and review of the literature.

Male breast cancer is rare and accounts for 1% of all breast cancers. The authors report two cases of male breast cancer at Stage III and review the literature. A Madden mastectomy with axillary clearance was performed. Patients were given adjuvant chemotherapy and started on tamoxifen. At one year follow-up the patients are alive and free from disease. Modified radical mastectomy is the preferred surgical approach for localized disease. Adjuvant hormonal therapy with tamoxifen is recommended as first-line treatment. Adjuvant chemotherapy has a role in node-positive cancer and locally advanced disease. Men should be made more aware of the disease and multicentric clinical trials encouraged to ensure an appropriate treatment on the basis of prospectively collected data.

In need of help.

I am a school nurse working in St Francis School for the Handicapped.

Molecular characterization of banana streak acuminata Vietnam virus isolated from Musa acuminata siamea (banana cultivar).

An isolate of banana streak virus (BSV) that does not also occur as an integrant in the Musa balbisiana genome was sought in order to investigate the biological role of BSV in the evolution of either the Musa genome or of the virus itself. We isolated BSV virions from a Musa acuminata siamea accession from Vietnam and sequenced the entire viral genome. The molecular organization is similar to that described for other BSV but slightly larger (7801 bp vs. 1611-7568 bp), and ORF I has a non-conventional start codon. This genome was sufficiently different to propose it as a member of a distinct species named Banana streak virus strain acuminata Vietnam (BSAcVNV).

The validity, reliability, reproducibility and extended utility of ankle to brachial pressure index in current vascular surgical practice.

BACKGROUND: Despite the increasing sophistication of vascular surgical practice, more than three decades after its introduction to clinical practice, the ankle to brachial pressure index (ABPI) remains the cornerstone of non-invasive assessment of the patient with symptomatic peripheral arterial disease (PAD). AIM: To summarise what is known about ABPI and critically appraise its validity, reliability, reproducibility and extended utility. METHODS: A MEDLINE (1966-2004) and Cochrane library search for articles relating to measurement of ABPI was undertaken; see text for further details. RESULTS: There is considerable disagreement as to how ABPI should be measured. Furthermore, various factors, including the type of equipment used, and the experience of the operator, can result in significant inter- and intra-observer error. As such, care must be taken when interpreting data in the literature. ABPI is valuable in the assessment of patients with atypical symptoms, venous leg ulcers and after vascular and endovascular interventions. However, absolute pressures are probably more valuable in patients with critical limb ischaemia. ABPI is also useful in subjects with asymptomatic PAD where it correlates well with, and may be used in screening studies to quantify, cardiovascular risk. CONCLUSIONS: While its apparent simplicity can beguile the unwary, ABPI will continue to have a key role in the assessment of symptomatic PAD. ABPI is also likely to have extended utility in health screening and institution of best medical therapy in asymptomatic subjects.

Assessment of 'once daily' verapamil for the treatment of hypertension using ambulatory, intra-arterial blood pressure recording.

A new, slow release formulation of verapamil, "verapamil o.d." was administered to 12 patients with essential hypertension. Drug administration was started at a dose of 240 mg and increased to 480 mg after 2 weeks of treatment if the cuff blood pressure response was unsatisfactory. The drug reduced the daytime intra-arterial blood pressure significantly from 180.7/106.8 mm Hg to 157.3/89.4 mm Hg. The daytime heart rate fell from 88.1 to 71.8 beats/min. The night-time blood pressure decreased from 155.7/87.2 mm Hg to 140.5/75.3 mm Hg. The nocturnal heart rate decreased from 62.8 to 57 beats/min. Hourly plots of mean systolic and diastolic pressure showed a significant reduction of systolic pressure for 21 of 24 h and of diastolic pressure for all 24 h following a single morning dose. The drug modified the absolute blood pressure and heart-rate response during both forms of exercise, but did not alter the magnitude or rate of blood pressure change. The tilt-test produced no evidence of postural hypotension. Only one patient experienced any side effects whilst taking the drug. These results indicate good 24-h blood pressure control and reduced exercise blood pressure levels during treatment with this new formulation of verapamil. The reduced frequency of drug administration should improve patient compliance with treatment of hypertension.

Isolation of human hepatocytes after hepatic warm and cold ischemia: a practical approach using University of Wisconsin solution.

A method is described for isolating human hepatocytes from tissue fragments after warm and cold ischemia as experienced during hepatic resections. Cells with a high trypan blue dye exclusion and good culture characteristics were isolated by employing an initial tissue perfusion with UW solution. The method could facilitate transfer of liver tissues between distant centers for cell isolation studies.