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Aims: To assess the risks of zoonotic agents in dissemination of livestock wastes into the environment by airborne distribution. To subsequently assess the survival time of zoonotic agents, introduced in irrigation water, on the phylloplane of produce. Methods and Results: An Escherichia coli marker was introduced into pig slurry which was spread using a rain gun sprayer. Air sampling was undertaken to determine the distance reached by the marker. No recoveries were observed at a distance of 250 m. Borehole water, contaminated with zoonotic agents, was used to irrigate field plots sown with lettuce and spinach. Decline in bacterial numbers on the phylloplane was observed with time. After initial rapid decreases, we were unable to detect any pathogen from the phylloplane, 1 month after contamination. Conclusions: These preliminary results suggest that the risks to public health from the aerosolized spread of bacteria during slurry spreading by rain gun are low. Although, zoonotic agents on crop phylloplanes perish quickly, the risks of overhead irrigation of fresh produce 3 weeks before harvest should still be considered. Significance and Impact of the Study: These preliminary results improve our understanding on the fate of zoonotic agents in the environment. Spreading liquid livestock wastes by an airborne mechanism may not pose a significant public health risk. Detection of zoonotic agents 3 weeks after contamination of lettuce and spinach means that consideration should be given by the farmers until the time of harvest, when irrigating fresh produce with water that may have been directly or indirectly contaminated by livestock wastes. [ABSTRACT FROM AUTHOR]

Aims: To determine if the temperatures used in feed manufacture are likely to destroy Escherichia coli O157. Methods and Results: Two commercial feeds were ground and inoculated with E. coli O157 cells. The feeds were heated to 50, 55, 60, 65 or 70°C. Heating produced quadratic survivor curves, with rapid initial decreases. The survival characteristics of E. coli O157 differed in the two feeds. The reductions observed in one feed may not have been due to heat alone. There was evidence that indigenous anti- E. coli O157 factor(s) in one feed acted with the heat and contributed to the observed rates of bacterial death. Heating at 70°C for 20 or 120 s resulted in approx. 1·3 and 2·2 log reductions in E. coli O157 numbers respectively. Lesser reductions were observed at lower temperatures. Conclusions: The time/temperature combinations used in commercial pelleting processes would not effectively kill high numbers of E. coli O157. Significance and Impact of the Study: This is the first study to look at the survival of E. coli O157 strains after heat treatment within concentrated animal feed. The study provides information on the likely risk of E. coli O157 surviving the animal feed manufacturing process. [ABSTRACT FROM AUTHOR]

Aims: Animal feeds ( n = 226), collected from pastures or feeding troughs on UK farms and from feed manufacturers’ bulk stores, were analysed for Escherichia coli harbouring shiga-toxin genes ( stx), faecal coliforms, coliphages and stx-harbouring bacteriophages. Methods and Results: Samples comprised of 79 fresh grasses, 26 silages and 121 dried or heat-processed feeds (DPF). Five of the 79 (6·3%) fresh grass samples contained stx2- E. coli. stx- E. coli were not detected in the silages or DPF that were examined. Faecal coliforms were detected in 75/79 (94·9%) of fresh grasses, 19/26 (73·1%) of silages and 36/121 (29·8%) of processed feeds. Coliphages were detected in 63/79 (79·7%) and 18/26 (69·2%) of fresh grasses and silages, respectively. Coliphages were isolated at a significantly lower prevalence of 5% (6/121) from processed feeds. Although stx2-phage was isolated from the enrichment of a single grass sample, stx-phages were not detected in any of the silage or processed feeds. We did not detect stx1-phage in any of the samples collected. Conclusions: Pastures have the potential to act as transmission vectors for stx-harbouring E. coli for grazed livestock. Significance and Impact of the Study: This is the first study to report on the prevalence of E. coli harbouring stx genes, faecal coliforms, coliphages and stx-harbouring bacteriophages in a range of feedstuffs destined for consumption by UK livestock. This study provides information on the risk of feeds to the spread of stx-phages between livestock and/or the environment. [ABSTRACT FROM AUTHOR]

m.l. hutchison, l.d. walters, s.m. avery and a. moore. 2005. To measure the rates of decline of zoonotic agents introduced into heaps of spent bedding and faecal wastes generated by commercially farmed livestock and managed in a similar way to that of a working farm. Livestock isolates of Salmonella, pathogenic Listeria, Campylobacter and Escherichia coli O157 were laboratory cultured and used to inoculate 5 m3 heaps of cattle, sheep or pig wastes mixed with bedding materials. Decline of each of the infectious agents was monitored with time as was the temperature inside each heap. Temperatures of >50°C were typically achieved at the core of the heaps. Pathogen decline was rapid, typically <3 days for a 1-log reduction in levels. The longest time that zoonotic agents were isolated from the heaps was 93 days. Movement of heaps of livestock bedding waste from animal pens to a secondary store, and storing them under conditions conducive for increased temperature is a simple and cost-effective treatment for rapidly lowering levels of zoonotic agents in solid farm wastes. This study demonstrates a simple and cheap treatment that can be used to help prevent the spread of zoonotic agents through agricultural environments. [ABSTRACT FROM AUTHOR]

Aim: To measure the decline rates of zoonotic agents introduced into liquid livestock wastes in on-farm storage tanks. Methods and Results: Salmonella spp., Escherichia coli O157, Campylobacter jejuni, Listeria monocytogenes and Cryptosporidium parvum, propagated in laboratory-controlled conditions, were inoculated into 35 000-1 volumes of fresh livestock wastes (pig slurries, cattle slurries and dirty waters). D-values for bacteria were six to 44 days, and for C. parvum were 133 to 345 days. Campylobacter jejuni declined significantly more rapidly than the other bacterial pathogens, while E. coli 0157 declined significantly more slowly. On average, bacterial declines were not affected by the season of waste deposition and storage or by the dry matter content of the wastes, but were more rapid in dirty waters than in pig slurries. The physiciochemical composition of wastes in each category varied significantly. Conclusions: Zoonotic agents can survive for several months during storage of liquid livestock wastes. Livestock wastes should be batch-stored and not subjected to continuous additions. Significance and Impact of the Study: This study indicates that batches of liquid livestock waste, if contaminated with bacterial pathogens, should be stored for 6 months to reduce contamination levels. Alternative strategies for reducing C. parvum levels in liquid livestock wastes should be explored. [ABSTRACT FROM AUTHOR]

s.m. avery, l.d. walters and m.l. hutchison. 2004.The fate of inoculatedEscherichia coliO157,stxphages and the physico-chemical properties of maize were studied during laboratory-scale fermentation by naturally occurring lactic acid bacteria.Before fermentation, chopped maize was inoculated with 6·2 log10 CFU g−1 of a five-isolate mixture ofE. coliO157. After fermentation, the silage contained 70·6 g kg−1 dry matter (DM) lactic acid and 12·8 g kg−1 DM acetic acid and was pH 4·0. Levels ofE. coliO157 fell rapidly, and none of the five isolates could be recovered from the fermenting maize after 8 days. Using a resuscitation step did not consistently enhance recovery ofE. coliO157.Stxphages were not isolated from the fermenting maize at any time. Pulsed-field gel electrophoresis (PFGE) genotyping showed thatE. coliO157 2975 and 64a/01 survived better than the other three isolates studied.Escherichia coliO157 isolate 1474/00 was particularly sensitive to the laboratory procedures used to harvest the inocula and contaminate the maize. Some colonies recovered during the fermentation had one to three band alterations compared with the initial PFGE genotypes.None of the five differentE. coliO157 genotypes survived maize fermentation. Fermentation of maize produces an animal feedstuff that is unlikely to containE. coliO157 orstxphages. [ABSTRACT FROM AUTHOR]

s.m. avery, a. moore and m.l. hutchison. 2004. To determine the fate of Escherichia coli deposited onto grassland via faeces, from naturally colonized cattle, sheep or pigs. Groups of cattle, sheep and pigs were penned outdoors on grass during November, and removed after 14 days. Escherichia coli populations in the ground declined over 134 days from initial average levels of 5·34, 4·31 and 4·96 log10 CFU g−1 in cattle, sheep and pig pens, respectively. The maximum Escherichia coli survival time was up to 162 days (190 days taking sampling interval and deposition time into account), but numbers varied significantly amongst the 20 replicates taken each day. Escherichia coli originating from cattle and sheep had average decimal reduction times ( D-values) of 38 and 36 days, respectively; E. coli originating from pigs declined significantly faster (average D-value of 26 days). Escherichia coli from livestock faeces can survive on grass for at least 5–6 months, affording opportunity for pathogenic biotypes to contaminate animals, plants or water. [ABSTRACT FROM AUTHOR]

The case for routine human immunodeficiency virus (HIV) screening of all couples seeking assisted reproductive treatment is so strong that it should be made obligatory for all couples entering IVF programmes to be given information about HIV transmission, and offered testing. In August 1999, questionnaires regarding routine HIV screening of couples seeking IVF treatment were sent to the medical directors of the 74 licensed assisted conception units in the UK. Of the 45 (60.8%) centres who responded, 19 (42.2%) routinely screen both partners for HIV antibodies, 25 (55.5%) do not screen and one centre selectively screens high-risk patients. There was no significant difference in the proportion of centres that routinely carried out screening with regards to the unit size: six out of 13 (46.2%) small units compared with 13/32 (40.6%) large units. In all, 17 centres (37.8%) rated HIV screening as essential, nine (20%) as desirable, 11 (24.4%) as not required, while eight (17. 8%) centres did not comment. Of the 19 centres that have a routine screening policy, 18 have management protocols in the event that the test is positive. Of these 18 centres, 12 adhere rigidly to the protocol, while five centres adhere to the protocol with few exceptions and the remaining one uses its protocol for guidance only. The main reasons for not employing routine HIV screening were: the lack of cost effectiveness, low prevalence of HIV infection in their population, necessity for and cost of counselling, uncertainty about the need for screening and potential delay to start of treatment. [ABSTRACT FROM AUTHOR]

Human spermatozoa have unusual cryobiological behaviour and improvements in their survival have not been achieved by the standard approaches of cryobiology. Conventional approaches to cryopreservation impose a linear change of temperature with time; however, the stresses that cells encounter during cryopreservation are all non-linear with time. In this paper it is shown that improved methods of cryopreservation may be developed by specifically manipulating the manner in which cells experience physical changes instead of imposing a linear temperature reduction. Several treatments were compared: control of solidification to achieve constant ice formation with time was more damaging than the standard linear reduction in temperature. However, treatments which followed a chosen non-linear concentration profile, referred to as 'controlled concentration' allowed recovery of almost all the cells which were motile before freezing. The biophysical basis of these different responses was examined using the cryostage of a scanning electron microscope and freeze substitution and it was found that, surprisingly, all samples of spermatozoa in the frozen state were neither osmotically dehydrated nor had any visible intracellular ice. Viability on thawing did not appear to correlate with conventional theories of cellular freezing injury, which suggests that for human spermatozoa other factors determine viability following freezing and thawing. [ABSTRACT FROM AUTHOR]

Between 1985 and 1989, one unilateral twin and four bilateral tubal pregnancies were encountered among 124 extrauterine pregnancies and 1648 intrauterine pregnancies following in-vitro fertilization and embryo transfer. The two factors associated with this high incidence of single and multiple extrauterine pregnancies were tubal damage and multiple embryo transfer. Embryos at different stages of development appear to have the capacity to implant ectopically. Despite advances in diagnostic capabilities, ectopic pregnancy remains a major cause of maternal mortality. Early diagnosis prior to rupture must be made if mortality and morbidity are to be abolished. The use of transvaginal sonography has improved the diagnosis of ectopic pregnancy and should be routinely used in all pregnancies following assisted conception. The identification of an intrauterine pregnancy should not be sufficient to rule out the possibility of an extrauterine pregnancy or even bilateral tubal pregnancies. [ABSTRACT FROM AUTHOR]

The lethal effects of various biocides, in particular two agents (chlorhexidine diacetate and polyhexamethylene biguanide) on cysts and trophozoites of Acanthamoeba castellanii have been measured by both plaque assay and flow cytometry (FCM). Minimum amoebicidal concentrations against trophozoites were generally the same by the two methods whereas minimum cysticidal concentrations were occasionally higher by FCM. Concentrations of biguanides required to produce an equal reduction in viability were also higher by FCM than by plaque assay. [ABSTRACT FROM PUBLISHER]

The improved survival in recent years of young males suffering from cancer, and an understanding of the gonadotoxic effects of chemotherapy treatment, have motivated patients and clinicians to preserve fertility potential before embarking on adjuvant therapy. Among 231 men (mean age 28.0; range 15-56 years) diagnosed with malignant disease and referred to our unit for semen cryopreservation, 112 patients (49.8%) had reduced sperm quality of <10 x 10(6) motile spermatozoa per ejaculate; however, most had sufficient suitable spermatozoa for freezing. In 40 patients (17.3 %) the semen samples were not frozen because of complete azoospermia (n = 32) or only immotile sperm in the ejaculate (n = 2), while six men were unable to produce a single sample. Some 79 men had testicular tumours (group I), 121 suffered from haematological malignancy (leukaemia or lymphoma; group II), and 27 had cancer of different causes (group III). Men in group I had significantly lower (P < 0.001) sperm quality compared with groups II and III. There was no difference between patients with seminoma and non-seminoma tumours. In the haematological malignancy group there was no difference in sperm parameters between leukaemia (n = 12) and lymphoma (n = 77) patients, but patients with Hodgkin's lymphoma had significantly lower sperm quality compared with non-Hodgkin's lymphoma. Following chemotherapy, six couples attended the clinic for assisted conception treatment using the frozen semen. Two had successful intrauterine insemination cycles which each resulted in delivery of a healthy girl; one couple had conceived in their first in-vitro fertilization (IVF) attempt, followed by delivery of healthy twins. Two women conceived after intracytoplasmic sperm injection treatment and the sixth woman achieved only biochemical pregnancy after numerous IVF and frozen embryo replacement cycles. We recommend that a properly designed programme for semen cryopreservation for cancer patients should be developed in leading tertiary assisted conception centres, which have adequate facilities and experience for cryopreservation and can offer the whole range of appropriate assisted reproductive treatment and counselling. [ABSTRACT FROM AUTHOR]

Infertility due to spinal cord injury (SCI) in young men is a frequent complication of their injury. When the simpler methods of management of the erectile and ejaculatory dysfunction that invariably follow the more severe types of SCI are not effective, then semen production by transrectal electroejaculation (TREE) combined with in-vitro fertilization (IVF) and embryo transfer is effective. A retrospective analysis is presented of data on the treatment and outcome of 35 couples who wished to have a family but in whom the male partner had suffered SCI. These 35 couples had 71 attempts at IVF with spermatozoa obtained following TREE. Normal fertilization and cleavage of the embryos occurred in 48.2% of the oocytes. Fresh embryos were transferred in 54 cycles and frozen-thawed embryos in 14 cycles. In all, 18 clinical pregnancies were achieved in 54 fresh and 14 frozen embryo transfer cycles, with a live birth rate of 16.5% (14/85) per treatment cycle started, 20.6% (14/68) per transfer cycle and 40.0% (14/35) per couple who started treatment, in a mean of 1.9 transfer cycles. We conclude that TREE combined with IVF and embryo transfer is an effective treatment for the infertility problems associated with SCI. [ABSTRACT FROM PUBLISHER]

The article presents information on a study regarding immunological investigation of individuals with toluene diisocyanate asthma. Thirteen subjects who experienced only the expected irritant respiratory and ocular effects from occupational exposure to toluene diisocyanate (TDI) were compared with eight workers who appeared clinically to be sensitized to this substance, as manifested by the prompt development of asthmatic symptoms on exposure to minute concentrations of TDI. Since TDI has a marked irritant action on mucous membranes, respiratory symptoms and injury would be expected following inhalation of high concentrations of this substance.

Cefazolin, a first generation cephalosporin, is a rare cause of cyclical fevers, neutropenia, and thrombocytopenia following surgical prophylaxis. We present the case of an otherwise healthy 21-year-old male who sustained a 50-cm laceration to his chest and abdomen. He received emergency department prophylaxis with cefazolin and surgical repair. Subsequently, he developed cyclical fevers, neutropenia, and thrombocytopenia, all of which resolved after antibiotic discontinuation. This is the first case report in which the perioperative administration of cefazolin following trauma resulted in significant neutropenia and thrombocytopenia. Also discussed in this report are the etiology, workup, and treatment of cefazolin-induced neutropenia. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the histopathological characteristics of endometrial biopsies taken on the day of oocyte recovery in in-vitro fertilization (IVF) cycles with a satisfactory response to ovulation induction. A group of 33 patients who went through ovulation induction for IVF, and in whom an endometrial polyp was suspected on transvaginal ultrasonography during the monitoring phase, were studied. Following oocyte recovery, hysteroscopy, polypectomy and endometrial curettage were performed. Dating of endometrial glands and stroma was carried out in the tissue not containing the polyps. The total dose of follicle stimulating hormone (FSH), duration of ovulation induction, peak oestradiol and luteinizing hormone (LH) concentrations, thickness of endometrium and number of oocytes were recorded and compared to the endometrial dating of the specimens. In 15 cycles (45.5%), the endometrium was classified as 'in phase' (group I), 'advanced' by 2-4 days in a further 15 (45.5%, group II), and in the remaining three cycles (9%) it was delayed in maturation (group III). Younger age was correlated with advanced staging of the endometrium (r = -0.42; P = 0.015). Women with 'in phase' and 'advanced' maturation were similar in their response to ovulation induction; however, there was a strong correlation between advanced dating of endometrium and number of oocytes retrieved (r = 0.49; P = 0.04). Endometrial staging on the day of oocyte retrieval varied widely in patients treated by the same gonadotrophin-releasing hormone agonist (GnRHa)/FSH protocol for ovulation induction. This difference was not predictable by parameters monitored through the cycles. [ABSTRACT FROM AUTHOR]

Two wives of a Muslim with severe male factor infertility had simultaneous intracytoplasmic sperm injection (ICSI) treatments. One wife developed ovarian hyperstimulation syndrome (OHSS), and 19 of 27 oocytes retrieved were subjected to ICSI but only one fertilized; the other wife had a normal response to ovarian stimulation, normal fertilization following ICSI, successful treatment and has recently delivered a live-born infant. The wife who suffered from OHSS has since had another ICSI cycle with a normal response to ovarian stimulation, a normal fertilization rate but no pregnancy. The only variable that determined the different rate of fertilization in the simultaneous ICSI cycles appears to be oocyte quality. While the results of frozen embryo replacement cycles following the decision to freeze all embryos following OHSS is generally satisfactory, it is important to counsel couples about the possible detrimental effects of OHSS on oocyte quality. [ABSTRACT FROM AUTHOR]

Two wives of a Muslim with severe male factor infertility had simultaneous intracytoplasmic sperm injection (ICSI) treatments. One wife developed ovarian hyperstimulation syndrome (OHSS), and 19 of 27 oocytes retrieved were subjected to ICSI but only one fertilized; the other wife had a normal response to ovarian stimulation, normal fertilization following ICSI, successful treatment and has recently delivered a live-born infant. The wife who suffered from OHSS has since had another ICSI cycle with a normal response to ovarian stimulation, a normal fertilization rate but no pregnancy. The only variable that determined the different rate of fertilization in the simultaneous ICSI cycles appears to be oocyte quality. While the results of frozen embryo replacement cycles following the decision to freeze all embryos following OHSS is generally satisfactory, it is important to counsel couples about the possible detrimental effects of OHSS on oocyte quality. Keywords: ICSI/OHSS/oocyte quality/surgical sperm retrieval [ABSTRACT FROM PUBLISHER]

We report the delivery of non-identical twins resulting from the combined transfer of one fresh and one frozen embryo to a 31 year old patient. To our knowledge, this is the first reported case where both a fresh and a frozen embryo implanted in the same cycle led to non-identical twins. We conclude that supernumerary embryos after in-vitro fertilization should be frozen and used in subsequent cycles, with implantation potentials as high as fresh embryos. The possibility of mixing fresh and frozen embryos, though rarely needed, should be considered, particularly when there is only one fresh embryo available for transfer. [ABSTRACT FROM AUTHOR]

We report the delivery of non-identical twins resulting from the combined transfer of one fresh and one frozen embryo to a 31 year old patient. To our knowledge, this is the first reported case where both a fresh and a frozen embryo implanted in the same cycle led to non-identical twins. We conclude that supernumerary embryos after in-vitro fertilization should be frozen and used in subsequent cycles, with implantation potentials as high as fresh embryos. The possibility of mixing fresh and frozen embryos, though rarely needed, should be considered, particularly when there is only one fresh embryo available for transfer. [ABSTRACT FROM PUBLISHER]