bluuebunny/crossref_metadata_2025 huggingface dataset:
Hepatitis C virus genotypes: distribution and clinical significance in patients with cirrhosis type C seen at tertiary referral centres in Europe
Authors: Fattovich G. , Ribero M. L. , Pantalena M. , Diodati G. , Almasio P. , Nevens F. , Tremolada F. , Degos F. , Rai J. , Solinas A. , Mura D. , Tocco A. , Zagni I. , Fabris F. , Lomonaco L. , Noventa F. , Realdi G. , Schalm S. W. , Tagger A. ,   the Eurohep Study Group on Viral Hepatitis
Published: March 2003

The aim of this study was to evaluate the distribution and clinical significance of hepatitis C virus (HCV) genotypes in European patients with compensated cirrhosis due to hepatitis C (Child class A) seen at tertiary referral centres. HCV genotypes were determined by genotype‐specific primer PCR in 255 stored serum samples obtained from cirrhotics followed for a median period of 7 years. Inclusion criteria were biopsy‐proven cirrhosis, absence of complications of cirrhosis and exclusion of all other potential causes of chronic liver disease. The proportion of patients with types 1b, 2, 3a, 1a, 4 and 5 were 69%, 19%, 6%, 5%, 0.5% and 0.5%, respectively. Kaplan–Meier 5‐year risk of hepatocellular carcinoma (HCC) was 6% and 4% for patients infected by type 1b and non‐1b, respectively (P=0.8); the corresponding figures for decompensation were 18% and 7% (P=0.0009) and for event‐free survival were 79% and 89% (P=0.09), respectively. After adjustment for baseline clinical and serological features, HCV type 1b did not increase the risk for HCC [adjusted relative risk=1.0 (95% confidence interval=0.47–2.34)], whereas it increased the risk for decompensation by a factor of 3 (1.2–7.4) and decreased event‐free survival by a factor of 1.7 (0.9–3.10). In conclusion, type 1b and, to a lesser extent, type 2, are the most common HCV genotypes in European patients with cirrhosis. HCV type 1b is not associated with a greater risk for HCC, but increases the risk for decompensation by threefold in patients with cirrhosis.
Genus Phyllanthus for chronic hepatitis B virus infection: a systematic review
Authors: Liu J. , Lin H. , McIntosh H.
Published: March 2003

To evaluate the efficacy and safety of genus Phyllanthus for chronic hepatitis B virus (HBV) infection we performed a systematic review of randomized clinical trials. Randomized trials comparing genus Phyllanthus vs. placebo, no intervention, general nonspecific treatment, other herbal medicine, or interferon treatment for chronic HBV infection were identified by electronic and manual searches. Trials of Phyllanthus herb plus interferon (IFN) vs. IFN alone were also included. No blinding and language limitations were applied. The methodological quality of trials was assessed by the Jadad scale plus allocation concealment. Twenty‐two randomized trials (n=1947) were identified. The methodological quality was high in five double‐blind trials and low in the 17 remaining trials. The combined results showed that Phyllanthus species had positive effect on clearance of serum HBsAg (relative risk 5.64, 95% CI 1.85–17.21) compared with placebo or no intervention. There was no significant difference on clearance of serum HBsAg, HBeAg and HBV DNA between Phyllanthus and IFN. Phyllanthus species were better than nonspecific treatment or other herbal medicines for the clearance of serum HBsAg, HBeAg, HBV DNA, and liver enzyme normalization. Analyses showed a better effect of the Phyllanthus plus IFN combination on clearance of serum HBeAg (1.56, 1.06–2.32) and HBV DNA (1.52, 1.05–2.21) than IFN alone. No serious adverse event was reported. Based on this review Phyllanthus species may have positive effect on antiviral activity and liver biochemistry in chronic HBV infection. However, the evidence is not strong due to the general low methodological quality and the variations of the herb. Further large trials are needed.
Acute pancreatitis complicating acute exacerbation of chronic hepatitis B infection carries a poor prognosis
Authors: Yuen M.‐F. , Chan T.‐M. , Hui C.‐K. , Chan A. On‐On , Ng I. Oi‐Lin , Lai C.‐L.
Published: March 2003

The clinical outcome of acute pancreatitis complicating acute exacerbation of chronic hepatitis virus B (HBV) infection has never been studied. Ninety patients with acute pancreatitis were recruited. Five patients (5.6%) (Group 1) had acute pancreatitis superimposed on acute exacerbation of chronic HBV infection with no other causes of acute pancreatitis being identified. The clinical outcome of these five patients was compared to the 85 non‐HBV infected patients (Group 2) with acute pancreatitis. A third group (Group 3) of patients (n=406) with acute exacerbation of chronic HBV infections without acute pancreatitis was also recruited for comparison. Group 1 had a significantly higher mortality rate (4 out of 5, 80%) compared to those of Group 2 (13 out of 85, 15.3%, P=0.0041) and Group 3 (9 out of 406, 2.2%, P < 0.0001). In Group 1 patients, the acute pancreatitis occurred during the initial rise of HBV DNA with relatively low or normal level of alanine aminotransferase (ALT) in two patients, during the rise of ALT with declining level of HBV DNA in one patient, and during the cholestatic phase of the acute exacerbation in one patient. The acute pancreatitis was clinically silent and only diagnosed by computerized tomography in the remaining patient. Direct viral damage and/or immunological attack to the pancreatic tissue were probably the underlying pathogenesis of the acute pancreatitis in these patients.

In conclusion, acute pancreatitis complicating acute exacerbation of chronic HBV infection carried an extremely poor prognosis with high mortality.
T‐cell antigenic determinants within hepatitis C virus nonstructural protein 3 and cytokine production profiles in hepatitis C
Authors: Pan C.‐H. , Yang P.‐M. , Hwang L.‐H. , Kao Shing‐F. , Chen P.‐J. , Chiang B.‐L. , Chen D.‐S.
Published: March 2003

summary. The aim of this study was to further investigate the role of T‐helper cells in hepatitis C virus (HCV) infection, focusing on the T‐cell antigenic determinants and cytokine profiles of nonstructural 3 (NS3) protein‐stimulated peripheral blood mononuclear cells (PBMCs) of HCV patients. A total of 12 recombinant proteins of theNS3 region were purified and used to test T‐cell proliferative response and antigenic determinants of HCV‐seropositive patients. In addition, cytokines produced by antigen stimulated PBMCs were measured. Our data showed that PBMCs from 55.7% (34/61) of HCV patients proliferated to at least one antigen, but PBMCs of HCV seronegative patients did not. In addition, PBMCs from about 82.0% (32/39) HCV‐seropositive patients produced significant amounts of cytokines (10 pg/mL). Interestingly, PBMCs from 66% of patients produced TH2‐related cytokines such as interleukin (IL)‐4 and IL‐5. In mappingexperiments, the data showed multiple T‐cell antigenic determinants. Our data demonstrated that NS3 antigen‐stimulated PBMCs of HCV patients recognized multiple T‐cell antigenic determinants and produced significant amounts of TH0 or TH2‐related cytokines, which might play a critical role in the chronicity of HCV infection.
Efficacy of prolonged 5 million units of interferon in combination with ribavirin for relapser patients with chronic hepatitis C
Authors: Fattovich G. , Zagni I. , Fornaciari G. , Minola E. , Fabris P. , Boccia S. , Giusti M. , Abbati G. , Felder M. , Rovere P. , Redaelli A. , Tonon A. , Montanari R. , Paternoster C. , Distasi M. , Castagnetti E. , Tositti G. , Rizzo C. , Suppressa S. , Pantalena M. , Lomonaco L. , Scattolini C. , Tagger A.
Published: March 2003

summary. Retreatment of relapser patients with chronic hepatitis C with the standard dose of interferon (IFN) of 3 million units (MU) thrice weekly (tiw) plus ribavirin for 24 weeks achieves a sustained response in 30 and 73% of patients with genotype 1 and 2 or 3, respectively. The aim of this study was to evaluate the efficacy and safety of IFN α‐2b induction therapy, followed by prolonged treatment with a high dose of IFN α‐2b plus ribavirin in relapser patients. A total of 119 patients were randomized to receive IFN α‐2b 5 MU daily (Group A: 59 patients) or IFN α‐2b 5 MU tiw (Group B: 60 patients) for 4 weeks followed by IFN (5 MU tiw) and ribavirin (1000–1200 mg/day) for 48 weeks in both groups. The primary end point was hepatitis C virus (HCV)‐RNA clearance at week 24 after the end of treatment. A sustained virological response (SVR) was achieved in 68 and 60% of Group A and B patients, respectively (P = 0.37). Logistic regression analysis identified genotype 2 or 3 as the only independent factor associated with response, whereas induction regimen and baseline viraemia levels did not affect the response. The overall SVR was 53 and 72% in patients with genotype 1 or 4 and 2 or 3, respectively. In conclusion, induction IFN therapy does not enhance the SVR to a 48‐week combination therapy. Our study suggests that relapsed patients with genotype 1 or 4 may achieve significant response rates of approximately 50%, if retreated with 5 MU tiw IFN plus ribavirin for 48 weeks.
Diving and ranging behaviour of odontocetes: a methodological review and critique
Authors: Hooker Sascha K. , Baird Robin W.
Published: March 2003

Movements can be analysed in terms of horizontal or vertical dimensions, but cetacean movement is ultimately three‐dimensional, and it is the integration of analyses of both horizontal and vertical movements that will provide the most insight about an animal's behaviour. Current field techniques can provide simultaneous information on both diving (vertical movements) and ranging (horizontal movements). We discuss the considerations, techniques and analyses for diving and ranging studies, together with the advantages and disadvantages of each technique. Ranging studies using VHF or satellite‐linked radio‐transmitters have evolved alongside studies of diving behaviour using time–depth recorders, and problems associated with deployment and attachment techniques apply to both. The diving (and concurrent ranging behaviour) of 13 species of odontocetes has been studied using time–depth recorders or acoustic transponders with VHF‐or satellite‐transmitters. However, differences in sampling techniques used, and summary statistics presented, have made comparisons difficult. We review these issues and suggest parameters that should be presented in future studies of diving and ranging. In general, studies should be consistent in their presentation of the basic parameters and statistics, and provide enough information for the reader to assess the limitations of the data.
The evolution of flight and echolocation in bats: another leap in the dark
Authors: Speakman John R.
Published: March 2003

The earliest known complete bats, from the Eocene (49–53 Mya), were already capable of flapping flight and echolocation. In the absence of direct fossil evidence there have been many speculative scenarios advanced to explain the evolution of these behaviours and their distributions in extant bats. Theories assuming chiropteran monophyly have generally presumed the ancestral pre‐bat was nocturnal, arboreal and insectivorous. Following this assumption hypotheses can be divided into the echolocation first, flight first and tandem development hypotheses, all of which assume that flight evolved only once in the lineage. In contrast, the chiropteran diphyly hypothesis suggests that flight evolved twice. Evidence supporting and refuting the different hypotheses are reviewed. It is concluded that there are significant problems attached to all the current models. A novel hypothesis is advanced, which starts from the assumption that bats are monophyletic and the ancestral pre‐bat was arboreal, but diurnal and frugivorous. After the evolution of flight it is suggested that these animals were driven into the nocturnal niche by the evolution of raptorial birds, and different groups evolved either specialised nocturnal vision (megachiropterans) or echolocation (microchiropterans). A block on sensory modality transfer has retained this distribution of perceptual capabilities ever since, despite some Megachiroptera evolving rudimentary echolocation, and the dietary convergence of some Microchiroptera with the Megachiroptera. The new hypothesis overcomes many of the problems identified in previous treatments.
On the evolution of the mammalian baculum: vaginal friction, prolonged intromission or induced ovulation?
Authors: Larivière S. , Ferguson S. H.
Published: March 2003

The function of the mammalian baculum is a puzzling enigma in mammalian morphology. Three hypotheses for the evolution and persistence of the mammalian baculum have been proposed: the vaginal friction hypothesis; the prolonged intromission hypothesis; and the induced ovulation hypothesis. We tested these three hypotheses using phylogenetically corrected methods and data on North American carnivores. Baculum length was independent of sexual dimorphism and duration of copulation, thus refuting the vaginal friction and prolonged intromission hypotheses, respectively. Also, baculum length did not differ between induced ovulators and simultaneous ovulators, thus also refuting the induced ovulation hypothesis. We suggest that other aspects of carnivore life history, such as mating systems, may help explain the evolution of the mammalian baculum.
Purring and similar vocalizations in mammals
Authors: Peters G.
Published: March 2003

The terms purr and purring have been used for vocalizations produced by a variety of mammalian species in different orders. A few other mammalian vocalizations that are structurally somewhat similar to felid purring but have been given another term have also been described in the literature. Because use of the same term implies ‘sameness’, which in an evolutionary sense can only mean that the vocalizations so named are homologous (= share the same ancestral vocalization type), the terms purr and purring ought to be restricted to vocalizations homologous with felid purring, and any mammalian vocalization homologous with felid purring ought to be named accordingly. According to present knowledge ‘true’ purring is established only in the families Viverridae and Felidae of the Carnivora. Vocalizations very similar in structure occur in matching behavioural contexts in other families of the Carnivora and several other mammalian orders. Most of these vocalization types are likely to have evolved convergently.
Mark–release–recapture experiments with Anopheles gambiae s.l. in Banambani Village, Mali, to determine population size and structure
Authors: TOURÉ, YEYA T. , DOLO GUIMOGO , PETRARCA VINCENZO , TRAORÉ,  , BOUARÉ,  , DAO ADAMA , CARNAHAN JOHN , TAYLOR CHARLES E.
Published: March 2003

Mark–release–recapture experiments with Anopheles gambiae s.l. were performed during the wet seasons of 1993 and 1994 in Banambani, Mali. All recaptured mosquitoes were identified to species by PCR analysis and, when possible, by chromosomal analysis to chromosomal form. Two species of the An. gambiae complex were present: An. gambiae s.s. and An. arabiensis; their ratio differed greatly from one year to the next. Three chromosomal forms of An. gambiae s.s. were found – Bamako, Savanna and Mopti. The drier 1993 was characterized by a high frequency of An. arabiensis and of the Mopti chromosomal forms of An. gambiae s.s. These trends were consistent with large‐scale geographical patterns of abundance along a precipitation gradient. We observed no difference in dispersal between the two species, nor among the chromosomal forms of An. gambiae s.s. Therefore, in this situation at least, it is reasonable to group such data on the An. gambiae complex as a whole for analysis. Population size of An. gambiae s.l. females in the village was estimated to be 9000–11 000 in 1993 and 28 000 in 1994. The corresponding numbers were somewhat higher when independently‐derived values of daily survival were used. These were consistent with estimates of effective population size obtained from patterns of gene frequency change.
A survey of the ixodid ticks parasitising cattle in the Eastern Province of Zambia
Authors: BERKVENS  , GEYSEN  , CHAKA  , MADDER  , BRANDT
Published: March 2003

The results of tick surveys carried out in the Eastern province of Zambia between December 1982 and February 1996 were principally in agreement with the findings of earlier surveys conducted during the period 1965–72. Boophilus decoloratus has almost been replaced by Boophilus microplus. Hyalomma truncatum was found in small numbers throughout the province and Hyalomma marginatum rufipes was only rarely encountered in collections made from cattle. Rhipicephalus evertsi evertsi was largely confined to the southern part of the plateau and the valleys of the Zambezi tributaries. The main difference between the present survey and the previous one concerns the status of Rhipicephalus appendiculatus. This species is currently expanding its range in a westward direction, whereas it was virtually absent from the southern part of the province during the period 1965–72. The majority of specimens collected are morphologically intermediate between R. appendiculatus and the closely allied Rhipicephalus zambeziensis. The available evidence indicates that R. zambeziensis (sensu stricto) is absent from the province. The phenology of R. appendiculatus is aberrant in the province: at lower altitudes a second generation of adult ticks is recorded on the hosts at the start of the dry season.
Seasonal and spatial changes in blowfly production from small and large carcasses at Durham in lowland northeast England
Authors: Davies L.
Published: March 2003

Colonization by blowflies (Diptera: Calliphoridae) of mouse carcasses exposed in open agricultural land near Durham (54°45′ N) changed from early spring monopolization by Calliphora vicina R.‐D. to a summer pattern of multiple species exploitation by this species together with Lucilia caesar L., L. illustris Mg., L. silvarum Mg., L. sericata Mg. and L. richardsi Collin.

 In a garden at the edge of Durham, mouse carcasses were dominated by C. vicina from spring to autumn. Difference in mouse colonization between the agricultural and garden sites seemed to reflect differences in the blowfly species present, as measured by baited trap catches at the sites.

 In sets of C. vicina reared from mice under conditions of competition for larval food, it was found that resulting females were significantly larger than males, size being measured as mean wing length.

 Blowfly production from three sheep carcasses exposed successively at the agricultural site was dominated by C. vomitoria L. and L. caesar, but also produced other Lucilia species in small numbers, including L. sericata. These L. sericata females from sheep that had died from causes other than myiasis included full‐sized specimens, in contrast to those produced from mouse carcasses that were all under‐sized individuals. As L. sericata females trapped on sheep pastures are predominantly full‐sized, this suggests that large carcasses may, in part, be a source of the L. sericata population that attacks sheep as a myiasis agent. The nature of large carcasses as possible sources of L. sericata in lowland Britain is discussed.
Pyrethroid resistance mechanisms in the head louse Pediculus capitis from Israel: implications for control
Authors: Hemingway J. , Miller J. , Mumcuoglu K. Y.
Published: March 2003

In Israel, the head louse, Pediculus capitis, developed resistance to DDT through the extensive use of this insecticide until the 1980s. In 1991, permethrin was introduced for control of DDT resistant P. capitis in Israel, leading to control failure of this pyrethroid insecticide by 1994. Pyrethroid resistance of P. capitis in Israel extends to phenothrin, which has not been used for louse control. We identified a glutathione S‐transferase(GST)‐based mechanism of DDT resistance in the Israeli head lice. This GST mechanism occurred before 1989, while permethrin resistance in P. capitis developed after 1994, suggesting that the main GST resistance mechanism selected by DDT use does not confer any pyrethroid cross‐resistance. Esterase activity levels were equivalent in pyrethroid resistant and susceptible P. capitis field‐collected in Israel, and in a susceptible strain of P.humanus, the body louse, indicating no involvement of any esterase‐based mechanism in resistance. A weak monooxygenase‐based permethrin metabolism resistance mechanism was the only factor identified which could account for any of the observed pyrethroid resistance in P. capitis. However, the lack of synergism of phenothrin resistance by piperonyl butoxide suggests that a non‐oxidative mechanism is also present in the resistant lice. Therefore it seems probable that pyrethroid resistance in Israeli P. capitis is due to a combination of nerve insensitivity (knockdown resistance or ‘kdr’) and monooxygenase resistance mechanisms.
Skin lesions and cattle hide damage from Haematobia irritans infestations
Authors: Guglielmone A. A. , Gimeno E. , Idiart J. , Fisher W. F. , Volpogni M. M. , Quaino O. , Anziani O. S. , Flores S. G. , Warnke O.
Published: March 2003

The horn fly Haematobia irritans L. (Diptera: Muscidae) has recently spread to Argentina and Uruguay and is believed to cause damage to cattle hides. Four groups of ten Holstein steers each were maintained for 58 weeks under different infestation levels with H. irritans to determine if it was the cause of this problem. Hides (chrome tanned) from steers maintained under minimum infestation level had 4.7 ± 3.8% of the area damaged. Maintaining the steers under low H. irritans level for the last 44 days of the trial using insecticidal ear‐tags, resulted in 29.5 ± 15.8% of hide area being damaged. Steers that were treated with 5% cypermethrin pour‐on, when the H. irritans population was close to 50 flies, showed that 31.3 ± 16.6% of hide area was injured, and 46.6 ± 12.8% of damaged hide area was found in hides from non‐treated steers. Significant differences were found between mean hide damage from steers maintained continuously under low H. irritans infestation levels and all other groups. Hyperaemia was significantly lower in the skin of steers under low H. irritans infestation level than in the skins of non‐treated steers and steers maintained under low‐level infestations for the final 44 days. Eosinophil and mononuclear cell infiltration was significantly lower when the population of H. irritans was less than six per steer than when the population was more than 100 flies per steer. Low numbers of Stomoxys calcitrans were found in all groups, but most hide damage was presumed due to H. irritans.
Impact of pyrethroid‐impregnated curtains on Phlebotomus papatasi sandflies indoors at Khartoum, Sudan
Authors: Elnaiem D. A. , Aboud M. A. , Mubarek S. G. EL. , Hassan H. K. , Ward R. D.
Published: March 2003

Laboratory and field investigations were made in an endemic focus of cutaneous leishmaniasis in Khartoum State, Sudan, to evaluate the effects of permethrin‐impregnated curtains on the human‐biting activity, nocturnal activity and resting behaviour of the vector sandfly Phlebotomus papatasi (Diptera: Psychodidae) indoors. Laboratory bioassays showed that curtains impregnated with 0.5, 1.0 or 1.5 g/m2 permethrin all gave 100% mortality within 24 h of exposure of P. papatasi for 3 min. Under natural field conditions, the biting activity indoors and the resting density of P. papatasi were significantly reduced (P < 0.001 and P = 0.036, respectively) in rooms provided with permethrin‐impregnated curtains as compared to control rooms left without curtains or fitted with unimpregnated curtains. No significant difference was found between the numbers of nocturnally active P. papatasi collected in rooms provided with impregnated curtains and rooms left without curtains or provided with unimpregnated curtains (P = 0.377). Evidently P. papatasi was not repelled by these doses of permethrin on curtains, but the survival rate of sandflies collected from test rooms provided with permethrin‐impregnated curtains was significantly reduced (P = 0.036). We conclude that use of permethrin‐impregnated curtains may provide a good control method for P. papatasi and other endophilic and/or endophagic sandfly vectors of leishmaniasis.
Population structure and dispersal of the saltmarsh mosquito Aedes vigilax in Queensland, Australia
Authors: Chapman H. F. , Hughes J. M. , Jennings C. , Kay B. H. , Ritchie S. A.
Published: March 2003

Population genetics of the mosquito Aedes vigilax (Skuse) (Diptera: Culicidae), a major vector of arboviruses (e.g. Barmah Forest, Ross River), were investigated to obtain an indirect estimate of mosquito dispersal characteristics in typical habitats of Aedes vigilax in south‐east Queensland: on the off‐shore islands of Moreton Bay and on the mainland where disjunct breeding populations of Ae. vigilax are distributed along intertidal marsh. Six allozyme loci were assessed for genetic differentiation between samples from 11 localities. Significant larval variation between some breeding sites was attributed to site‐specific selection. Non‐significant genetic differentiation was found among collections of adult mosquitoes caught in light traps throughout the study area (exceeding 60 × 27 km), indicating widespread dispersal. As distances of ≤ 9 km over water did not appear to act as effective barriers to Ae. vigilax dispersal, localized control activities applied to Ae. vigilax breeding sites are unlikely to be effective against the vagile adult population. Therefore, the contiguous shires programme of broad acre control is endorsed to prevent the spread of arboviruses carried by Ae. vigilax
Insecticide resistance in Brazilian Triatoma infestans and Venezuelan Rhodnius prolixus
Authors: Vassena C. V. , Picollo M. I. , Zerba E. N.
Published: March 2003

Resistance levels to insecticides used in control of Chagas Disease vectors were assessed in two species of bugs (Hemiptera: Reduviidae): Triatoma infestans (Klug) from Brazil and Rhodnius prolixus Stål from Venezuela. The resistance ratios, compared to susceptible laboratory strains, were determined by topical application bioassays. The T. infestans PA strain exhibited resistance ratios of 7× to deltamethrin, 3.6× to β‐cyfluthrin and 3.3× to cypermethrin, but was susceptible to β‐cypermethrin and lambda‐cyhalothrin. Rhodnius prolixus CA strain showed resistance to all the pyrethroids evaluated, the resistance ratios ranging between 4.5× to lambda‐cyhalothrin and 12.4× to cypermethrin. Deltamethrin resistance in both strains was decreased by piperonyl butoxide, suggesting oxidative metabolism as cause of resistance.
Resistance to dieldrin + fipronil assorts with chromosome inversion 2La in the malaria vector Anopheles gambiae
Authors: Brooke B. D. , Hunt R. H. , Coetzee M.
Published: March 2003

Cyclodiene insecticide resistance in malaria vector mosquitoes of the Anopheles gambiae species complex (Diptera: Culicidae) has been reported previously from several parts of Africa. We report resistance to dieldrin, a cyclodiene, in two laboratory strains of An. gambiae Giles sensu stricto code‐named Ian P20 from Nigeria (1979) and CIG from Cote d'Ivoire (1997). Dieldrin resistance levels were high in adult female mosquitoes (40–75% survived exposure to 4% dieldrin for 1 h) and was closely linked with chromosomal paracentric inversion 2La. This inversion did not occur in Hardy–Weinberg proportions, but showed an excess of heterozygotes in both strains, which may account for the high levels of resistance. This linkage also suggests that dieldrin resistance in Ian P20 is dominant. After subsamples of strain Ian P20 were exposed for 1 h to dieldrin 4% or fipronil 2% (discriminating concentrations), the resultant mortality‐rates (61% and 65%) were not significantly different. Most survivors after fipronil treatment also survived subsequent exposure to dieldrin (46/50 = 92%). This apparent cross‐resistance between insecticides of two classes (cyclodiene and phenyl pyrazole) has implications for the management of insecticide resistance in wild populations of the An. gambiae complex.
Rates of development ofHydrotaea rostrataunder summer and winter (cyclic and constant) temperature regimes
Authors: Dadour I. R. , Cook D. F. , Wirth N.
Published: March 2003

The black carrion flyHydrotaea rostrataRobineau‐Desvoidy (Diptera: Muscidae) is a muscid, which occurs on approximately one‐third of decomposing human corpses involved in homicide cases in south‐western Australia. Work to date on its development rates is scant with only one published source available. The current study measured the precise developmental rates of this species using high repetition and sampling rates. A comparison was made of the developmental rates between constant and cyclic temperatures in winter and summer temperature regimes in south‐western Australia. Developmental times for 90% of first stage larvae to emerge as adult flies are: summer constant, 21.6 days, summer cyclic, 23.5 days, winter constant 64.5 days and winter cyclic, 48.3 days. These data will allow forensic entomologists to make more accurate determinations of post‐mortem intervals in cases whereH. rostratalife history stages are present.
Diptera as vectors of mycobacterial infections in cattle and pigs
Authors: Fischer O. , Mátlová L. , Dvorská L. , . Švástová P , Bartl J. , Melichárek I. , Weston R. T. , Pavlík I.
Published: March 2003

Mycobacteria were isolated from 14 (4.5%) of 314 samples, containing 7791 adult Diptera, which were collected in the Czech Republic and Slovakia in 1997–2000. These flies were collected from three cattle herds with paratuberculosis, two pig herds with mycobacterial infections and one farm that kept both cattle and pigs and that did not have problems of mycobacterial infections. Mycobacterium intracellulare was isolated from Eristalis tenax Linnaeus (Diptera: Syrphidae) captured from a pig herd. Mycobacterium avium ssp. avium (serotype 8) was isolated from flies of the genera Drosophila Fallén (Diptera: Drosophilidae) and Musca Linnaeus (Diptera: Muscidae) originating from a pig herd. Mycobacterium spp. were isolated from Musca spp. and Mycobacterium fortuitum was isolated from dung flies of the genus Scatophaga Meigen (Diptera: Scatophagidae), Musca spp. and Stomoxys calcitrans Linnaeus (Diptera: Muscidae) captured in the same herd. Mycobacterium scrofulaceum was isolated from S. calcitrans from the farm with both cattle and pigs. Mycobacterium avium ssp. paratuberculosis was isolated from Scatophaga spp. collected from pastures grazed by one of the cattle herds and from Calliphora vicina Robineau‐Desvoidy (Diptera: Calliphoridae) and Lucilia caesar Linnaeus (Diptera: Calliphoridae) captured in a slaughterhouse, where cattle infected with paratuberculosis were slaughtered. Mycobacterium phlei was isolated from flies of the genus Lucilia captured at a waste bin. These data indicate that mycobacteria may be spread by adult flies that have been in contact with material contaminated with these pathogens.
Annual cycles of four flea species in the central Negev desert
Authors: KRASNOV B. R. , BURDELOVA N. V. , SHENBROT G. I. , KHOKHLOVA I. S.
Published: March 2003

Abstract Bionomics of fleas (Siphonaptera) parasitizing rodent hosts, mostly the gerbil Gerbillus dasyurus (Wagner) and the jird Meriones crassus Sundevall (Gerbillidae), were investigated in the central Negev desert of Israel. Populations were sampled weekly (by Sherman trapping of hosts) from August 2000 to July 2001. Among 1055 fleas of nine species captured, four species predominated (94%). Two species of Pulicidae, Xenopsylla dipodilli Smit and X. ramesis (Rothschild), reproduced perennially, whereas adults of Nosopsyllus iranus theodori Smit (Ceratophyllidae) and Stenoponia tripectinata medialis Jordan (Hystrichopsyllidae) occurred only in cool months (October–March). During their main activity season on the most infested host species (estimated from > 300 trap‐nights/month), prevalence of these four flea species reached 40–70%, 20–30%, 100% and 50–70%, respectively, with infestation intensities of 2–2.7, 7–12, 2–3.5 and 2.5–7 fleas per infested rodent, respectively.

Xenopsylla dipodilli oviposition peaked during autumn with parous rate > 80% by September–October. During December–April, the majority of X. dipodilli females were immature and/or nulliparous (defined as having mature ovaries but no follicular relics). In contrast, X. ramesis had two reproductive peaks, in mid‐spring and autumn, evidenced by the influx of immature females in late spring and summer (30–40%) and in winter (20–30%) after maximal parous rates: 80–100% in March–April and 95–100% in October–November.

Nosopsyllus iranus theodori and Stenoponia tripectinata medialis adults occurred only during cool months. At the beginning of activity, during October–November, the sex ratio of N. i. theodori was strongly biased to females (86%) that were immature and/or nulliparous. In winter, adult females were 52–65% parous and 10–32% immature. In March, as the adult population of N. i. theodori declined, 78% of females were parous and 12% immature. Seasonal activity of S. t. medialis (November–March) was shorter than for the other three species; females were predominantly nulliparous in November (80%), after which the proportion of parous females increased gradually to 84% in February. Two females of S. t. medialis collected in March were mature but nulliparous, suggesting that this species of flea might ‘oversummer’ (as pupae or teneral adults) in the cocooned stage.
Isoenzyme variation in Aedes aegypti correlated with Dirofilaria immitis infectability
Authors: Nayar J. K. , Knight J. W.
Published: March 2003

Abstract From the Vero Beach strain of the mosquito Aedes (Stegomyia) aegypti (L.) (Diptera: Culicidae), substrains were selected for susceptibility (SS) and refractoriness (RR) to the dog heartworm Dirofilaria immitis (Leidy) (Filarioidea: Onchocercidae). These two lines and their reciprocal F1 hybrids were analysed for genetic variation at 14 enzyme loci, using polyacrylamide gel electrophoresis. Six of the enzyme loci showed variation (sample size 48 alleles/locus/line). Three of these were monomorphic in the refractory line but polymorphic in the susceptible, i.e. aconitase hydratase (Acoh), isocitrate dehydrogenase‐1 (Idh‐1) and phosphoglucomutase (Pgm).

The other three loci, glucose‐6‐phosphate isomerase (Gpi), hexokinase‐1 (Hk‐1) and isocitrate dehydrogenase‐2 (Idh‐2), were polymorphic in both SS and RR lines and their hybrids. At two loci (Hk‐1, Pgm) three alleles were detected, whereas the other polymorphic loci had only two alleles. For Hk‐1, the most frequent allele was Hk‐180 (0.563) in refractory and Hk‐1100 in the susceptible (0.521) and F1 hybrids. For Pgm the most frequent alleles were Pgm125 in the susceptible line (0.646) and Pgm100 in the F1 hybrids (0.563 and 0.604) and refractory line (1.000). The mean observed heterozygosity (Ho), the mean Hardy–Weinberg expected heterozygosity (He) and the mean number of alleles per locus in the refractory line were lower, but not significantly so, than in the susceptible line and their reciprocal F1 hybrids; the proportion of polymorphic loci was significantly lower in the refractory than in the susceptible line and their F1 hybrids. Within both lines all polymorphisms were in Hardy–Weinberg equilibrium, whereas significant departures from predicted frequencies were observed in SS × RR hybrids at four polymorphic loci (Acoh, Gpi, Hk‐1, Pgm) and at three polymorphic loci (Acoh, Hk‐1, Pgm) in RR × SS hybrids. The average Nei's and modified Rogers' genetic distances between the lines were 0.024 and 0.139, respectively. These electrophoretic data show that the refractory line (putatively lacking fi allele) can be distinguished from the susceptible line ( fi/fi) and their hybrids (heterozygous fi) by isozyme marker frequencies, but it remains to be seen whether this difference is causal or chance linkage. In any case, this model system of Ae. aegypti/D. immitis provides opportunities to better understand and manipulate the molecular biology of filariasis transmission.
Latin American biomedical publications: the case of Colombia in Medline
Authors: Rosselli Diego
Published: March 2003

Latin America generates a low proportion of the references quoted in Medline, the most popular health‐related literature search database in the world. This paper explores references from and about Colombia in Medline during the period 1987–1996. Topics addressed, patterns of authorship and research locations are established. The number of Latin American journals indexed in Medline has been progressively reduced during this 10‐year period, with Colombian journals completely excluded since 1991. During this 10‐year period, the total output of Colombian research institutions in foreign journals consisted of 531 articles, 41% (219) of which come from the four leading universities. These figures are substantially lower than those from other countries of the region such as Venezuela or Chile. Despite some governmental efforts, Colombia continues to have a low scientific output and has yet to attract the interest of foreign researchers. Alternatives for development of Latin American research and publications are offered.
An evaluation of the `short form' course experience questionnaire with medical students
Authors: Broomfield Darice , Bligh John
Published: March 2003

In this study we have validated the Course Evaluation Questionnaire (CEQ) as an instrument for use with undergraduate medical students. We have demonstrated satisfactory construct validity and reliability for the inventory. The CEQ is an appropriate instrument for course evaluation in medical education.
Experiences of volunteer patients during undergraduate examinations: printed information can lead to greater satisfaction
Authors: Welfare  , Price  , Han  , Barton
Published: March 2003

Background

 Whilst most patients are happy to participate in medical examinations, previous studies have shown that some are dissatisfied with the information that they receive beforehand.

Objectives

 To demonstrate that patient satisfaction can be improved by the provision of written information.

Methods

 Thirty‐seven patients attending the final MBBS examination were sent written information about what to expect. The patients' experiences were assessed by means of an anonymous postal questionnaire 1 week after the examination. Their satisfaction with the level of information received beforehand was compared with that of an historical cohort who had received no written information

Results

 The patients had few complaints about their experience of participating in examinations and many enjoyed it. Only 5% of patients registered dissatisfaction with the level of information that was provided, compared with 18% in the previous study (P = 0·077).

Conclusions

 Written information led to a (near significant) improvement in patients satisfaction when compared to a previous cohort. We recommend that all patients attending for medical examinations should be provided with written information.
Comparative phylogeography and the history of endemic vertebrates in the Wet Tropics rainforests of Australia
Authors: SCHNEIDER C. J. , CUNNINGHAM M. , MORITZ C.
Published: March 2003

We examine the effects of historical climate change on vertebrate differentiation in tropical rainforest by comparing phylogeographic patterns in six species of widespread rainforest‐restricted herpetofauna from throughout the Wet Tropics of Australia. Qualitative and quantitative comparisons of phylogeographic structure reveal strikingly similar patterns of pre‐Pleistocene vicariant population differentiation on either side of a previously identified biogeographic break (variously referred to as the Black Mountain Barrier or Corridor; BMC). While divergence across the BMC antedates the Pleistocene, the impact of Quaternary climate change is apparent in populations on either side of the BMC. Consistent with palaeoclimatological reconstructions for the region, the distribution and degree of mtDNA diversity suggests that populations were fragmented and reduced to multiple refugia during Pleistocene glacial periods, with expansion following Holocene rainforest recovery. This pattern is repeated on both sides of the BMC, but substantial differences in the amount and distribution of mtDNA diversity within species indicate the importance of species‐specific ecological characteristics. The historical processes of extinction and (re)colonization revealed by the comparative phylogeographic analysis of mtDNA sequences substantiate earlier suggestions that current regional patterns of species distribution and diversity in the Wet Tropics are largely determined by local extinctions and subsequent recolonization driven by Quaternary climate changes.
Statistical confidence for likelihood‐based paternity inference in natural populations
Authors: MARSHALL T. C. , SLATE J. , KRUUK L. E. B. , PEMBERTON J. M.
Published: March 2003

Paternity inference using highly polymorphic codominant markers is becoming common in the study of natural populations. However, multiple males are often found to be genetically compatible with each offspring tested, even when the probability of excluding an unrelated male is high. While various methods exist for evaluating the likelihood of paternity of each nonexcluded male, interpreting these likelihoods has hitherto been difficult, and no method takes account of the incomplete sampling and error‐prone genetic data typical of large‐scale studies of natural systems. We derive likelihood ratios for paternity inference with codominant markers taking account of typing error, and define a statistic Δ for resolving paternity. Using allele frequencies from the study population in question, a simulation program generates criteria for Δ that permit assignment of paternity to the most likely male with a known level of statistical confidence. The simulation takes account of the number of candidate males, the proportion of males that are sampled and gaps and errors in genetic data. We explore the potentially confounding effect of relatives and show that the method is robust to their presence under commonly encountered conditions. The method is demonstrated using genetic data from the intensively studied red deer (Cervus elaphus) population on the island of Rum, Scotland. The Windows‐based computer program,CERVUS, described in this study is available from the authors.CERVUScan be used to calculate allele frequencies, run simulations and perform parentage analysis using data from all types of codominant markers.
A 5.8S nuclear ribosomal RNA gene sequence database: applications to ecology and evolution
Authors: CULLINGS KENNETH W. , VOGLER DETLEV R.
Published: March 2003

We compiled a 5.8S nuclear ribosomal gene sequence database for animals, plants, and fungi using both newly generated and GenBank sequences. We demonstrate the utility of this database as an internal check to determine whether the target organism and not a contaminant has been sequenced, as a diagnostic tool for ecologists and evolutionary biologists to determine the placement of asexual fungi within larger taxonomic groups, and as a tool to help identify fungi that form ectomycorrhizae.
Sequence analysis of the mitochondrial DNA control region of ciscoes (genus Coregonus): taxonomic implications for the Great Lakes species flock
Authors: REED KENT M. , DORSCHNER MICHAEL O. , TODD THOMAS N. , PHILLIPS RUTH B.
Published: March 2003

Sequence variation in the control region (D‐loop) of the mitochondrial DNA (mtDNA) was examined to assess the genetic distinctiveness of the shortjaw cisco (Coregonus zenithicus). Individuals from within the Great Lakes Basin as well as inland lakes outside the basin were sampled. DNA fragments containing the entire D‐loop were amplified by PCR from specimens of C. zenithicus and the related species C. artedi, C. hoyi, C. kiyi, and C. clupeaformis. DNA sequence analysis revealed high similarity within and among species and shared polymorphism for length variants. Based on this analysis, the shortjaw cisco is not genetically distinct from other cisco species.
Chloroplast DNA phylogeography of Alnus glutinosa (L.) Gaertn.
Authors: ANDREW KING R. , FERRIS COLIN
Published: March 2003

Traditionally, information on the postglacial history of plant species has been gained from the analysis of fossil pollen data. More recently, surveys of present patterns of genetic variation have given valuable insights into species phylogeography. The genus Alnus, based on fossil data, is known to have had at least four glacial refugia. A survey of chloroplast DNA (cpDNA) diversity in populations of black alder (A. glutinosa) was undertaken in order to gain more insight into its postglacial history. This revealed a high degree of structuring of 13 cpDNA haplotypes on a European scale which indicated that most of northern and central Europe was colonized from a refuge in the Carpathian Mountains. Based on the distribution of two common cpDNA haplotypes, colonization routes from this refuge can be determined. The locations of other previously identified refugia are confirmed and two formerly unconfirmed refugial areas for alder (southern Spain and Turkey) are proposed.
Random amplified polymorphic DNA (RAPD) markers reveal less genetic variation in the endangered plant Cerastiumfischerianum var. molle than in the widespread conspecific C. fischerianum var. fischerianum (Caryophyllaceae)
Authors: Maki M. , Horie S.
Published: March 2003

Random amplified polymorphic DNA (RAPD) analysis was used to assess the level of genetic diversity in an endangered plant Cerastiumfischerianum var. molle and the widespread conspecific C. fischerianum var. fischerianum. At both the variety and the population level, C. fischerianum var. molle had a lower level of RAPD variation than var. fischerianum. Analysis of molecular variance (
AMOVA) showed that most of the genetic diversity exists among populations for both varieties. Genetic differentiation among populations probably resulted from the highly selfing habits of both varieties. To conserve C. fischerianum var. molle genetically, preservation of only a part of the population is insufficient.
Costs of transgenic herbicide resistance introgressed from Brassica napus into weedy B. rapa
Authors: Snow ALLISON A. , Andersen BENTE , Jørgensen RIKKE BAGGER
Published: March 2003

Wild relatives of genetically engineered crops can acquire transgenic traits such as herbicide resistance via spontaneous crop–wild hybridization. In agricultural weeds, resistance to herbicides is often a beneficial trait, but little is known about possible costs that could affect the persistence of this trait when herbicides are not used. We tested for costs associated with transgenic resistance to glufosinate when introgressed into weedy Brassica rapa. Crosses were made between transgenic B. napus and wild B. rapa from Denmark. F1 progeny were backcrossed to B. rapa and BC1 plants were selected for chromosome numbers similar to B. rapa. Further backcrossing resulted in a BC2 generation that was hemizygous for herbicide resistance. We quantified the reproductive success of 457 BC3 progeny representing six full‐sib families raised in growth rooms (plants were pollinated by captive bumblebees). Pollen fertility and seed production of BC3 plants were as great as those of B. rapa raised in the same growth rooms. Segregation for herbicide resistance in BC3 plants was 1:1 overall, but the frequency of resistant progeny was lower than expected in one family and higher than expected in another. There were no significant differences between transgenic and nontransgenic plants in survival or the number of seeds per plant, indicating that costs associated with the transgene are probably negligible. Results from this growth‐chamber study suggest that transgenic resistance to glufosinate is capable of introgressing into populations of B. rapa and persisting, even in the absence of selection due to herbicide application.