Widespread antibiotic resistance in savannah Nigeria

There is minimal data on antibiotic resistance from savannah northern Nigeria. A retrospective study of 438 patients seen in 12 months (2000) with microbial pathogens from urinary and respiratory tracts was undertaken. Antibiotic susceptibilities were determined using stokes disc diffusion technique. Resistance in Escherichia coli (E. coli) reached 91-96% to cotrimoxazole, tetracycline and ampicillin but was 11%, 17% and 28% to colistin, nitrofurantoin and nalidixic acid. Resistance of other uropathogens (Klebsiella and Proteus spp) reached 83-99% to cotrimoxazole, tetracycline and ampicillin but was 14-40% to colistin, nitrofurantoin and nalidixic acid. Pneumococci were non-susceptible to penicillin (93%), cotrimoxazole (92%), tetracycline (84%), ampicillin (53%), chloramphenicol (21%) and cefazolin (8%). Antibiotic resistance is widespread in savannah northern Nigeria. Resistance is less to chloramphenicol, colistin, nalidixic acid, nitrofurantoin and the latter generation cephalosporins and quinolones than to penicillin, ampicillin, cotrimoxazole and tetracycline.

99mTcO(BAT-NI), a novel nitroimidazole tracer: in vivo uptake studies in ischaemic myocardium

Myocardial perfusion single-photon emission tomography (SPET) performed with cationic technetium-99m complexes indicates ischaemic areas as cold lesions. By contrast, nitroimidazole derivatives labelled with fluorine-18 or (99m)Tc have recently shown promising results for hot spot imaging of ischaemic myocardium. This study evaluates (99m)TcO(BAT-NI), a new (99m)Tc complex comprising the nitroimidazole ligand, 2,10-dimercapto-2,10-dimethyl-4,8-diaza-6-[4-(2-nitroimidazolyl)butyl]undecane, in a low-flow in vivo model of myocardial ischaemia in thoracotomised rats. To elucidate the influence of the 2-nitroimidazole group on ischaemia-induced uptake, comparisons with ligand derivatives were performed where (a) the 2-nitro group was deleted [(99m)TcO(BAT-I)], (b) the 2-nitroimidazole functionality was replaced by a Br atom [(99m)TcO(BAT-Br)] and (c) the (99m)TcO(BAT) moiety was replaced by an iodine-125 iodophenoxybutyl ligand ((125)IP-NI). The radiolabelled compounds were i.v. injected 15 min after reducing resting myocardial blood flow by 50-60% and the uptake of radioactivity was assessed 90 min post injection. Autoradiography of left ventricular short-axis slices showed median uptake ratios of ischaemic/non-ischaemic myocardium (I/N) of 3.4, 4.5 and 3.4 for (99m)TcO(BAT-NI), (99m)TcO(BAT-I) and (99m)TcO(BAT-Br), respectively. In contrast, (125)IP-NI was not preferentially taken up by ischaemic myocardium. Accumulation of (99m)TcO(BAT-NI) in ischaemic heart regions was comparable to that in the liver. Biodistribution studies showed a median uptake of 0.65% ID/g of (99m)TcO(BAT-NI) in ischaemic tissue and an I/N of 3.3. On planar images of the thorax and upper abdomen the ischaemic hearts were visualised faintly; the median heart to lung count ratio for (99m)TcO(BAT-NI) was 1.7, and the median heart to liver count ratio was 1.0. We conclude that uptake of (99m)TcO(BAT-NI) in ischaemic myocardium does not depend on the nitroimidazole moiety but is intrinsic to the BAT complex. Clinical use of the (99m)TcO(BAT)-labelled tracers seems unlikely owing to their low uptake and their low ischaemic tissue contrast on planar images in vivo.

Water, food and environment: conflict or dialogue?

Increased water conflicts are the result of the rapidly increasing relative water scarcity in many basins to which water institutions have not yet successfully adapted. The Dialogue on Water, Food and Environment is a program of activities that employs processes at international, national, basin and local scales to help build bridges between agriculture and the environment.

The diagnostic dilemma of intraoperative hyperpyrexia in a malaria endemic area

Malignant hyperthermia (MH) is a serious and feared complication of general anaesthesia. The diagnosis of MH may pose a diagnostic dilemma, as its two most common signs tachycardia and hyperthermia are also common features of infections, transfusion and drug reactions. We report three cases of hyperthermia occurring during anaesthesia posing diagnostic dilemma in which two of the cases appear to be due to malaria. It is therefore suggested that all patients undergoing anaesthesia in a malaria endemic area should be investigated and treated for malaria if indicated preoperatively even when asymptomatic to prevent such diagnostic confusion.

Characterization of nitride thin films by electron backscatter diffraction

Thin films incorporating GaN, InGaN and AlGaN are presently arousing considerable excitement because of their suitability for UV and visible light-emitting diodes and laser diodes. However, because of the lattice mismatch between presently used substrates and epitaxial nitride thin films, the films are of variable quality In this paper we describe our preliminary studies of nitride thin films using electron backscattered diffraction (EBSD). We show that the EBSD technique may be used to reveal the relative orientation of an epitaxial thin film with respect to its substrate (a 90 degrees rotation between a GaN epitaxial thin film and its sapphire substrate is observed) and to determine its tilt (a GaN thin film was found to be tiltedby 13 +/- 1 degrees towards [1010]GaN), where the tilt is due to the inclination of the sapphire substrate (cut off-axis by 10 degrees from (0001)sapphire towards (1010)sapphire). We compare EBSD patterns obtained from As-doped GaN films grown by plasma-assisted molecular beam epitaxy (PA-MBE) with low and high As4 flux, respectively. Higher As4 flux results in sharper, better defined patterns, this observation is consistent with the improved surface morphology observed in AFM studies. Finally, we show that more detail can be discerned in EBSD patterns from GaN thin films when samples are cooled.

Audit of orthopaedic bed utilisation

Blockage of beds on an orthopaedic ward causes multiple problems; it can result in cancellation of patients or elective surgery, longer waiting lists and a crisis with emergency admissions. This often necessitates 'boarding out' of patients, which is not ideal for optimal patient care. Not all patients on an orthopaedic ward need continuing orthopaedic medical or nursing care and it may be more appropriate for these patients to be managed in a rehabilitation environment. From 1/09/98-30/11/98 data were collected on all patients admitted to an adult orthopaedic ward. Information recorded included the reason for admission, age, diagnosis, surgical procedure, family and social circumstances. In addition, the date when discharge was deemed appropriate was recorded as well as the actual date of discharge. We defined the length of overstay as the time spent in an orthopaedic bed after discharge had been deemed appropriate. There were 621 patients admitted for a total of 3159 bed days. There were 253 elective admissions and 368 emergency admissions. A total of 255 bed days were blocked by 46 patients (41 emergency and 5 elective) accounting for eight per cent of the total bed days. Of these 236 (93%) were due to emergency admissions and 19 (7%) were due to elective admissions, most blocked beds were due to patients who required rehabilitation in either a unit for the young disabled or a geriatric rehabilitation ward.

Radon progeny in Egyptian underground phosphate mines

In addition to the workers in uranium mines, the staff of other underground mines, such as workers in underground phosphate mines, can be exposed to 222Rn and its progeny. In this study the individual radon progeny concentrations were measured in three Egyptian underground phosphate mines to estimate the occupational exposure of the workers at those sites. A filter method was used to measure individual radon progeny concentrations (218Po, 214Pb and 214Po). The reported mean values of radon progeny concentrations exceed the action levels which are recommended by ICRP 65 (1993). Based on the measured individual radon progeny concentrations (218Po, 214Pb and 214Po) in these mines, the annual effective dose for the workers has been calculated using the lung dose model of ICRP 66 (1994). According to the obtained results, some countermeasures were recommended in this study to minimise these exposure levels.

Percutaneous transluminal angioplasty and stenting of coeliac artery stenosis in the treatment of mesenteric angina: a case report and review of therapeutic options

We report the case of a 72-year-old gentleman with mesenteric angina who was successfully treated with stenting of a coeliac artery stenosis using a Palmaz stent, and review the therapeutic options in the management of mesenteric angina.

Preparation and evaluation of tumor-targeting peptide-oligonucleotide conjugates

Enormous progress has been made in the development of antisense oligodeoxynucleotides (ODNs) as therapeutic agents inhibiting gene expression. Unfortunately, the therapeutical application of ODNs is still held back because of the low cellular uptake and the lack of specific transport into particular cells. In this paper, we report a drug-targeting system using somatostatin receptors (SSTRs) which are overexpressed in various tumors. Phosphorothioate ODNs were covalently linked to Tyr(3)-octreotate, an analogue of somatostatin. The peptide was assembled by solid-phase synthesis, oxidized to form the cyclic disulfide, and subsequently derivatized with a N-terminal maleimido functionality. 5'-Thiol derivatized phosphorothioate-ODNs directed against the protooncogene bcl-2 were conjugated to this maleimido-modified peptide. Binding studies revealed that the conjugates retain specific binding with nanomolar affinities to SSTRs (IC(50)-values between 1.83 and 2.52 nM). Furthermore, melting studies with complementary DNA revealed that the terminal conjugation of the ODNs did not significantly affect their hybridization affinity.

Radioiodinated N-(2-diethylaminoethyl)benzamide derivatives with high melanoma uptake: structure-affinity relationships, metabolic fate, and intracellular localization

Several radioiodinated N-(dialkylaminoalkyl)benzamides have been used for planar scintigraphy and single-photon emission computed tomography (SPECT) of melanoma metastases. In a quest for improved melanoma uptake and tissue selectivity, structure-activity studies for N-(2-diethylaminoethyl)benzamides with variation of phenyl substituents were performed using C57Bl/6 mice bearing B16 melanoma. Compounds 2 (4-amino-5-bromo-N-(2-diethylaminoethyl)-3-[(131)I]iodo-2-methoxybenz amide) and 6 (4-acetamido-N-(2-diethylaminoethyl)-5-[(131)I]iodo-2-methoxybenzamid e) showed at 6 h post iv injection, for example, melanoma uptake of 16.6 and 23.2% ID/g, respectively (mean values, n = 3). Uptake was 3-5 times higher (P < 0.01) than observed with benzamides known from the literature and was probably facilitated by the relatively slow urinary excretion of 2 or 6. In contrast, analogues lacking either the MeO, Ac, AcNH, or Br substituents exhibited reduced tumor uptake and high urinary excretion of radioactivity in various benzamide metabolites. Uptake of radioiodinated benzamides in B16 melanoma is not mediated by a specific mechanism such as sigma-receptor binding. 2 and 6 exhibited similar melanoma uptake values but quite different sigma(1)-receptor affinities of K(i) = 0.278 +/- 0.018 and 5.19 +/- 0.40 microM, respectively. Uptake studies with IMBA (N-(2-diethylaminoethyl)-3-[(131)I]iodo-4-methoxybenzamide) or BZA (N-(2-diethylaminoethyl)-4-[(131)I]iodobenzamide) showed that with increasing dose of unlabeled compound the measured uptake of label was unchanged (IMBA) or even enhanced (BZA) while receptor binding of label decreased. Differential and equilibrium density-gradient centrifugation revealed that most of the radioactivity from labeled IMBA was associated with fractions containing melanin granules. Thus, structure-activity studies indicate that blood clearance rates and metabolic stability are the main determinants for benzamide uptake in melanoma. The high uptake and slow clearance of 6 offer considerable potential for melanoma imaging in patients, and this compound may also prove to be useful for radionuclide therapy.

Notification of occupational diseases by general practitioners in the Western Cape

BACKGROUND

Notification of occupational diseases to the Department of Labour (and in limited situations to other agencies) is an important aspect of surveillance and planning for interventions as well as compensation. A survey of general practitioners (GPs) was conducted to assess their knowledge and practice with regard to reporting of occupational diseases.

DESIGN

Descriptive telephonic survey.

SETTING

Independent general practices in the Western Cape.

PARTICIPANTS

One hundred and forty GPs were randomly selected from a provincial sampling frame of 1,000 GPs.

MAIN OUTCOME MEASURES

Knowledge of notification procedures for occupational diseases, and problems encountered with the reporting system.

RESULTS

Of a total of 109 GPs interviewed, 75% had diagnosed more than one case of occupational disease in the last 6 months. Twenty-four per cent of the total (95% confidence interval (CI) 16-32%) indicated that they were aware of the notification requirements, and 5% (95% CI 0.8-9%) knew the appropriate legislation. Only one GP notified the appropriate authority once the diagnosis was made. Factors influencing their reporting practice included lack of guidelines for diagnosis of common work-related conditions, lack of information regarding referral channels, problems with communicating with the patient and employer, and poor knowledge of the reporting process itself. Lack of motivation as a result of poor feedback on cases reported and the labour-intensive administration required, were also cited as factors.

CONCLUSION

Although the majority of GPs diagnose occupational diseases, knowledge and practice regarding notification are poor. Recommendations to overcome obstacles to notification include a simplified, uniform notification system, adequate training and support of GPs, and timeous feedback to GPs.

The impact of brushing teeth on carbon-14 urea breath test results

OBJECTIVE

The 14C urea breath test noninvasively detects the presence of the urease-producing bacteria Helicobacter pylori in the stomach. Several sources of errors have been identified to cause false or indeterminate results on the test. The objective of this study was to identify whether brushing teeth affects the test results.

METHODS

We performed the 14C urea breath test on 168 patients, with breath samples counted at 10 and 20 min after oral administration of 2 microCi (74 kBq) 14C urea. Ninety-four patients brushed their teeth before the test while 74 did not.

RESULTS

Thirty-six of the 74 patients (49%) who did not brush their teeth had positive results at 10 min, which became negative at 20 min. None of the 94 patients who brushed their teeth before testing showed this pattern with agreement of results at 10 and 20 min.

CONCLUSION

We recommend brushing teeth before the 14C urea breath test since it significantly decreased the ambiguous results of the test in our laboratory.

'3+1' mixed-ligand oxotechnetium(V) complexes with affinity for melanoma: synthesis and evaluation in vitro and in vivo

'3+1' Mixed-ligand [(99m)Tc]oxotechnetium complexes with affinity for melanoma were synthesized in a one-pot reaction. Complexation of technetium-99m with a mixture of N-R(3-azapentane-1,5-dithiol) [R = Me, Pr, Bn, Et(2)N(CH(2))(2)] and N-(2-dialkylamino)ethanethiol [alkyl = X = Et, Bu, morpholinyl] using Sn(2+) as the reducing agent resulted in the formation of '3+1' mixed-ligand technetium-99m complexes [TcO(SN(R)S)(SNX(2))] in high radiochemical yield (60-98%). In vitro uptake studies in B16 murine melanoma cells indicated a moderate tumor-cell accumulation (40%) of compound 1 [R = Me, X = Et] and a higher accumulation (69%) of compound 2 [R = Me, X = Bu] after a 60-min incubation. In vivo evaluation of compounds 1-6 in the C57Bl6/B16 mouse melanoma model demonstrated tumor localization. Compound 2 displayed the highest accumulation with up to 5% ID/g at 60 min after injection. In vivo, 2 also showed a low blood-pool activity and high melanoma/spleen (4.3) and melanoma/lung (1.9) ratios at 1 h. These results suggest that small technetium-99m complexes could be useful as potential melanoma-imaging agents.

Morphological investigation of the rat kidney after continuous administration of testosterone, dihydrotestosterone, or dehydroepiandrosterone using TCPL delivery devices

The response of the kidney tissues to steroids, mainly dehydroepiandrosterone (DHEA), testosterone (T) and dihydrotestosterone (DHT) has been used extensively to investigate the mechanisms of steroid action on hypertension. The specific objective of this study was to investigate anatomical characteristics of kidney tissue after sustained delivery of DHEA, DHT or T at physiological or supraphysiological doses using adult male rats as a model. A total of eighteen adult male Sprague Dawley rats were divided randomly into six equal groups. Animals in groups I-V were implanted intraperitoneally with a single tricalcium phosphate lysine delivery system (TCPL) loaded with T (physiological dose), T (supraphysiological dose), DHT (physiological dose), DHT (supraphysiological dose), and DHEA (physiological dose), respectively. Animals in Group VI were implanted with empty TCPL capsules and served as sham controls. At the end of 21 days post implantation, the animals in each group were sacrificed and the kidneys were harvested, processed, embedded, sectioned and screened for cellular alterations. Data obtained from this study have shown physiological doses DHEA or supraphysiological doses of DHT and T had a significant effect on the areas of the glomeruli, without disruption or changes in area of proximal tubules. Histological evaluation of the organs (5 microns, H&E) revealed nephrotic hypotrophy in all kidneys obtained from animals given supraphysiological doses of DHT or T in comparison to sham animals.

Evaluation of potato tuber moth (Lepidoptera: Gelechiidae) resistance in tubers of Bt-cry5 transgenic potato lines

The potato tuber moth, Phthorimaea operculella (Zeller), in tropical and subtropical countries, is the most destructive pest of potato, Solanum tuberosum L. The larvae attack foliage and tubers in the field and in storage. The purpose of this study was to evaluate the efficacy of a Bt-cry5 transgene to control the potato tuber moth in tuber tissues. Tuber bioassays using stored (11-12 mo old) and newly harvested tubers of Bt-cry5-Lemhi Russet and Bt-cry5-Atlantic potato lines showed up to 100% mortality of 1st instars. Mortality was lowest in the newly harvested tubers of Bt-cry5-Atlantic lines (47.1-67.6%). Potato tuber moth mortality was 100% in the Bt-cry5-Spunta lines that were transformed with Bt-cry5 gene controlled by the CaMV 35S promoter (pBIML5 vector) and in 2 of 3 lines transformed with Bt-cry5 gene controlled by the Gelvin super promoter (pBIML1 vector). The transgenic Spunta lines expressing Bt-cry5 controlled by the patatin promoter (pBMIL2 vector) showed the lowest tuber moth mortality (25.6 and 31.1%). The Bt-cry5 transgenic lines with high tuber expression of B. thuringiensis have value in an integrated pest management system to control potato tuber moth.

Clinical utility of anticardiolipin antibody assays: high inter-laboratory variation and limited consensus by participants of external quality assurance programs signals a cautious approach

Antibodies that bind phospholipid (anti-phospholipid antibodies [APA]) are a focus of major interest to both clinical and laboratory personnel across a variety of disciplines because of the assortment of disorders with which they are reportedly associated. A solid phase assay using cardiolipin as the test phospholipid (anti-cardiolipin antibody assay [ACA]) has now become a laboratory standard for the detection of APA. In the current report, data from two separate external quality assurance programs (QAP) and collected over the past four years, have been evaluated to assess the utility of the ACA. Despite attempted standardizations, exceedingly high inter-laboratory variation and a general lack of test result consensus would signal the adoption of a cautious clinical approach towards laboratory findings. For example, for a total of 21 cross-laboratory tested serum samples (tested for both IgG and IgM for 41 quantitative estimations), inter-laboratory variation for both ACA-IgG and ACA-IgM was higher than 50% in 20 of 41 testing cases (48.8%). The situation with regard to testing consensus was equally concerning. Total consensus (i.e., 100% of participating laboratories agreed that a given serum sample gave an ACA result of either negative or positive) occurred in less than 20% of cases for ACA-IgG. More importantly, in about 50% of serum testing occasions there was no general consensus in returned laboratory data (i.e., more than 80% of labs could not agree on whether a serum sample tested was either ACA-positive or ACA-negative). Thus, despite attempted international standardizations, exceedingly high inter-laboratory variation and a general lack of test result consensus would argue that the assay has limited utility. We conclude that single point laboratory results must be used with considerable caution before accepting that ACA activity is present in patient serum or not. We agree with recommendations indicating that laboratory tests should be repeated at least once prior to making a clinical diagnosis of any APS-like disorder.

Radiation dose to the human respiratory tract from inhalation of radon-222 and its progeny

In this article the regional dose equivalent for exposure to 1 working level month (WLM), the annual effective dose equivalent and the dose equivalent conversion factor due to the inhalation of short-lived radon progeny (218Po, 214Pb and 214Bi/214Po) are calculated with a dosimetric model. Experimental results of aerosol size characteristics, unattached activity fractions, equilibrium factors, and activity size distributions of the short-lived radon progeny in indoor and outdoor atmosphere are summarized. Dose calculations based on these results show that the changes in dose rate values are influenced by the different model assumptions concerning deposition probabilities of aerosol particles in the respiratory system during inhalation, the sensitivity of different cells (epithelial, basal) to radiation and assuming nose or mouth breathing. The inverse relationship between the unattached fraction of potential alpha-particle energy in room air and the radioactive equilibrium between radon gas and its progeny indicates that dose equivalent is closely related to the concentration of radon gas averaged over a period of exposure.

Changing indications for penetrating keratoplasty in the west of Scotland from 1970 to 1995

In an attempt to predict the trends which might occur in the changing patterns of corneal surgery in the next decade and hence the financial implications, a retrospective study of the treatment of corneal disease was carried out using the pathological reports issued during the last 25 years in the West of Scotland Ophthalmic Pathology Service. This is a supra-regional specialist service which covers the major population areas in Scotland, although most of the specimens were submitted by consultants in the teaching hospitals in Glasgow. The major indications for surgery in the 1486 specimens received were post-inflammatory scarring (387 cases), repeat penetrating keratoplasty (309), keratoconus (257), Fuchs' dystrophy (120) and secondary endothelial failure after cataract surgery (158). In the past 6 years the indications changed and the commonest indications were secondary endothelial failure and post-inflammatory scarring. The study demonstrates a regional difference when compared with other reports and highlights the increasing demand for penetrating keratoplasty and the consequent resource implications.