PubMed Health⌕ Search

Biomedical subjects

D Jessup

Publications and source records attributed to D Jessup.

12 recordsLinked to original sources
PubMed2006

Salmonella spp., Vibrio spp., Clostridium perfringens, and Plesiomonas shigelloides in marine and freshwater invertebrates from coastal California ecosystems.

The coastal ecosystems of California are highly utilized by humans and animals, but the ecology of fecal bacteria at the land-sea interface is not well understood. This study evaluated the distribution of potentially pathogenic bacteria in invertebrates from linked marine, estuarine, and freshwater ecosystems in central California. A variety of filter-feeding clams, mussels, worms, and crab tissues were selectively cultured for Salmonella spp., Campylobacter spp., Escherichia coli-O157, Clostridium perfringens, Plesiomonas shigelloides, and Vibrio spp. A longitudinal study assessed environmental risk factors for detecting these bacterial species in sentinel mussel batches. Putative risk factors included mussel collection near higher risk areas for livestock or human sewage exposure, adjacent human population density, season, recent precipitation, water temperature, water type, bivalve type, and freshwater outflow exposure. Bacteria detected in invertebrates included Salmonella spp., C. perfringens, P. shigelloides, Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio alginolyticus. Overall, 80% of mussel batches were culture positive for at least one of the bacterial species, although the pathogens Campylobacter, E. coli-O157, and Salmonella were not detected. Many of the same bacterial species were also cultured from upstream estuarine and riverine invertebrates. Exposure to human sewage sources, recent precipitation, and water temperature were significant risk factors for bacterial detection in sentinel mussel batches. These findings are consistent with the hypothesis that filter-feeding invertebrates along the coast concentrate fecal bacteria flowing from land to sea and show that the relationships between anthropogenic effects on coastal ecosystems and the environmental niches of fecal bacteria are complex and dynamic.

Animals↗
PubMed2005

New genotypes and factors associated with Cryptosporidium detection in mussels (Mytilus spp.) along the California coast.

A 3 year study was conducted to evaluate mussels as bioindicators of faecal contamination in coastal ecosystems of California. Haemolymph samples from 4680 mussels (Mytilus spp.) were tested for Cryptosporidium genotypes using PCR amplification and DNA sequence analysis. Our hypotheses were that mussels collected from sites near livestock runoff or human sewage outflow would be more likely to contain the faecal pathogen Cryptosporidium than mussels collected distant to these sites, and that the prevalence would be greatest during the wet season when runoff into the nearshore marine environment was highest. To test these hypotheses, 156 batches of sentinel mussels were collected quarterly at nearshore marine sites considered at higher risk for exposure to livestock runoff, higher risk for exposure to human sewage, or lower risk for exposure to both faecal sources. Cryptosporidium genotypes detected in Haemolymph samples from individual mussels included Cryptosporidium parvum, Cryptosporidium felis, Cryptosporidium andersoni, and two novel Cryptosporidium spp. Factors significantly associated with detection of Cryptosporidium spp. in mussel batches were exposure to freshwater outflow and mussel collection within a week following a precipitation event. Detection of Cryptosporidium spp. was not associated with higher or lower risk status for exposure to livestock faeces or human sewage sources. This study showed that mussels can be used to monitor water quality in California and suggests that humans and animals ingesting faecal-contaminated water and shellfish may be exposed to both host-specific and anthropozoonotic Cryptosporidium genotypes of public health significance.

Animals↗
PubMed2005

Anaesthesia of nyala (Tragelaphus angasi) with a combination of thiafentanil (A3080), medetomidine and ketamine.

A combination of thiafentanil (A3080), medetomidine hydrochloride (MED) and ketamine hydrochloride (KET) was evaluated in 19 boma-habituated (12 female and 7 males) and 9 free-ranging nyala (7 male and 2 females) (Tragelaphus angasi) to develop a safe and reliable anaesthesia protocol. Wide dosages were used safely during this study with ranges for A3080 of 45 +/- 8 microg/kg with MED of 69 +/- 19 microg/kg and KET of 3.7 +/- 1.0 mg/kg (200 mg/ animal). The dosages developed on boma-habituated nyala proved to be equally effective in 9 adult free-ranging nyala (7 males and 2 females). The optimum dosage for nyala was a combination of A3080 (40-50 microg/kg), MED (60-80 microg/kg) plus 200 mg of KET/animal. The anaesthesia was characterised by a short induction, good muscle relaxation and mild hypoxaemia during monitoring the anaesthesia was rapidly and completely reversed by naltrexone hydrochloride (30 mg/mg of A3080) and atipamezole hydrochloride (5 mg/mg of MED) given intramuscularly. There was no mortality or morbidity associated with this protocol.

Anesthesia↗
PubMed2002

Evaluation of an indirect fluorescent antibody test (IFAT) for demonstration of antibodies to Toxoplasma gondii in the sea otter (Enhydra lutris).

An indirect fluorescent antibody test (IFAT) for detection of Toxoplasma gondii infection was validated using serum from 77 necropsied southern sea otters (Enhydra lutris nereis) whose T. gondii infection status was determined through immunohistochemistry and parasite isolation in cell culture. Twenty-eight otters (36%) were positive for T. gondii by immunohistochemistry or parasite isolation or both, whereas 49 (64%) were negative by both tests. At a cutoff of 1:320, combined values for IFAT sensitivity and specificity were maximized at 96.4 and 67.3%, respectively. The area under the receiver-operating characteristic curve for the IFAT was 0.84. A titer of 1:320 was used as cutoff when screening serum collected from live-sampled sea otters from California (n = 80), Washington (n = 21), and Alaska (n = 65) for T. gondii infection. Thirty-six percent (29 out of 80) of California sea otters (E. lutris nereis) and 38% (8 out of 21) of Washington sea otters (E. lutris kenyoni) were seropositive for T. gondii, compared with 0% (0 out of 65) of Alaskan sea otters (E. lutris kenyoni).

Alaska↗
PubMed2001

Anaesthesia of gemsbok (Oryx gazella) with a combination of A3080, medetomidine and ketamine.

An effective anaesthesia protocol was developed for adult free-ranging gemsbok (Oryx gazella) using a combination of A3080, medetomidine and ketamine. A short induction time; good muscle relaxation, adequate oxygenation and stable heart rate and respiration rate characterised this anaesthetic regime. Equal doses of A3080 and medetomidine (22-45 microg/kg) plus 200 mg of ketamine were administered to each animal. The anaesthesia was rapidly and completely reversed by intramuscular naltrexone at a dose of X = 0.9 +/- 0.2 mg/kg and atipamezole at a dose X +/- 90 +/- 20 microg/kg. No mortality or morbidity occurred with this protocol.

Analgesics↗
PubMed1993

Characterization of an Anaplasma ovis isolate from desert bighorn sheep in southern California.

To understand the role of bighorn sheep (Ovis canadensis) in the epidemiology of anaplasmosis, we recovered a field isolate from a suspected enzootic area in southern California (USA). Whole blood was collected from three desert bighorn sheep (Ovis canadensis nelsoni) and inoculated into a susceptible splenectomized domestic sheep, calf and a susceptible spleen-intact bighorn sheep. No infection occurred in the calf, but a detectable infection developed in both the domestic sheep and bighorn sheep 24 days after inoculation. The infection in both domestic and bighorn sheep resulted in severe clinical disease but was resolved with the use of tetracycline. Using monoclonal antibodies and DNA probes, we confirmed that the isolate was Anaplasma ovis.

Anaplasma↗
PubMed1990

Morphometric analysis of Psoroptes spp. mites from bighorn sheep, mule deer, cattle, and rabbits.

A morphometric study of Psoroptes spp. mites was conducted to address difficulties encountered in species identification and to provide insights into the phylogenetic relationships between mites found on different hosts. A discriminant analysis employing 9 morphologic characters revealed that the lengths of the outer opisthosomal setae and the lateral margins of the opisthosomal knobs were the 2 most important characters for grouping mites according to host species. This analysis clearly separated mites collected from allopatric populations of bighorn sheep, rabbits, and cattle into discrete groups. However, differences were not detected between mites collected from sympatric populations of infested mule deer and bighorn sheep, suggesting that these mites were not host specific and represented a single interbreeding population. Differences also were not detected among mites collected from the ears and body of bighorn sheep and rabbits, demonstrating that the location of mites on a given host should not be used as a primary criterion in species identification.

Animals↗
PubMed1985

Support of the luteal phase in in vitro fertilization programs: results of a controlled trial with intramuscular Proluton.

There is disagreement among in vitro fertilization (IVF) programs as to the need to administer exogenous progesterone to support the luteal phase of patients undergoing embryo transfer after IVF. We examined the effect on pregnancy rates of Proluton, 50-mg daily injections given on days 7-16 following oocyte recovery, in 186 women undergoing IVF treatment using a combined stimulation regime of clomiphene and human menopausal gonadotropin (hMG). One group was deliberately selected for treatment on the possible criterion of luteal-phase deficiency and two other groups were randomly selected into a treatment and a control group. No effect on pregnancy rate was noted in any of these groups. These results indicate that extension of the luteal phase with exogenous progesterone is unlikely to have a significant effect on increasing the pregnancy rate in IVF programs using similar treatment regimes.

17 alpha-Hydroxyprogesterone Caproate↗
PubMed1982

The technique for human embryo transfer.

In a program of human in vitro fertilization (IVF), the results of 204 attempted intracervical embryo transfers (ETs), using a variety of catheters in three trials over 18 months, have been analyzed for the ease of transfer and pregnancy rate. In nulliparous patients, transfers were more difficult than in multiparous patients; and a closed-end Teflon catheter was found to be more easily passed through the smaller cervical canal than an open-end catheter. The overall pregnancy rate was 17% (March 1980 to August 1981) and was not related to catheter type, although when chemical pregnancies were excluded, it was found that transfers using open-end catheters were more successful. The transfer procedure developed finally for routine use incorporates a consideration of these results.

Embryo Transfer↗
PubMed1981

A clinical assessment of nine pregnancies obtained by in vitro fertilization and embryo transfer.

An analysis of nine pregnancies resulting from in vitro fertilization and embryo transfer was made in order to identify factors common to all of the pregnancies. These factors included clomiphene stimulation; general anesthesia for laparoscopy; identification of large follicles (greater than 8 ml) and a mature oocyte; preincubation of the oocyte for 4.7 to 6.5 hours in vitro before insemination; insemination with 0.8 to 1.3 x 10(6) fresh spermatozoa from fertile samples; transfer to the uterus of two-, four-, and eight-cell embryos, 38 to 50 hours after insemination; and uncomplicated uterine transfers of embryos. It was difficult to determine whether these factors are causal or coincidental in the attainment of successful pregnancies. The detailed analysis was useful in demonstrating factors which did not prevent the establishment of pregnancy by in vitro fertilization and embryo transfer. These factors included a variety of causes of infertility, including idiopathic and male infertility; age of the infertile woman over 35 years; the presence of T-mycoplasma in the genital tract; the use of human chorionic gonadotropin; a variety of agents used for general anesthesia; the use of carbon dioxide to induce pneumoperitoneum; a delay of up to 50 minutes in the interval between the induction of general anesthesia and oocyte recovery; the use of antiprostaglandins at the time of embryo transfer; and a brown discharge from the vagina following embryo transfer.

Embryo Transfer↗