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T C Jones

Publications and source records attributed to T C Jones.

At least 19 recordsLinked to original sources
PubMed2001

High gene flow levels lead to gamete wastage in a desert spider system.

Field censuses, breeding experiments, and a quantitative model are used to obtain insight into the extent and consequences of genetic mixing between locally adapted populations of a desert spider. Typically, 9% of the matings of desert riparian spiders (non-aggressive phenotype) in native habitat involve an arid-land partner (aggressive phenotype). Mating was found to be random with respect to behavioral phenotype, but linearly related to both the rate of immigration and survival of immigrants from surrounding arid habitats in the riparian area. Genetic mixing between riparian and arid-land spiders produces offspring that exhibit lower rates of survival in riparian habitat. Two extreme behavioral phenotypes were also observed in the field studies: approximately 5% of the female spiders attacked all males they encountered while another 22% ran from all potential mates. Punnett square analyses of the potential genotypes produced by introgression between arid- and riparian-adapted spiders indicate that these extreme phenotypes appear in F2 generation hybrids and backcrosses. Because there is a costly wastage of gametes in the case of mixed phenotype mating, model results indicate that within three generations of the cessation of gene flow, the riparian population would be free of mixed genotypes and moving towards genetic differentiation.

Alleles↗
PubMed2000

Extra-pair paternity in waved albatrosses.

We estimated the rate of extra-pair fertilizations (EPFs) in waved albatrosses (Phoebastria irrorata) on Isla Española, Galápagos, Ecuador, using multilocus minisatellite DNA fingerprinting. Waved albatrosses are socially monogamous, long-lived seabirds whose main population is on Española. Aggressive extra-pair copulation (EPC) attempts have been observed in the breeding colony during the days preceding egg-laying. Our genetic analyses of 16 families (single chicks and their attending parents) revealed evidence of EPFs in four families. In all cases males were the excluded parent. These data suggest that waved albatrosses have an unusually high rate of EPF relative to taxa with similar life histories. Future behavioural observations will determine the extent to which forced vs. unforced EPCs contribute to this high EPF rate.

Animals↗
PubMed2000

Retrieval success is accompanied by enhanced activation in anterior prefrontal cortex during recognition memory: an event-related fMRI study.

Neural regions associated with retrieval success were identified using event-related fMRI procedures and randomly ordered trials on a recognition memory test. Differences between hits and correct rejections (CRs) occurred multiple regions, including bilateral anterior and right dorsolateral prefrontal cortex, bilateral inferior parietal cortex, and right superior parietal cortex (all hits > CRs), and right occipital cortex (CRs > hits). The hit > CR pattern is not compromised by time-on-task explanations because response latencies for correctly rejected words exceeded those for hits. Converging evidence for the claim that the hit > CR pattern identified neural correlates of retrieval success was obtained by unconfounding item history and retrieval success. That is, we implemented a third condition in which nonstudied words were presented, yet retrieval success was hypothesized to facilitate CRs of these lures. Specifically, in when confronted with a familiar, yet nonstudied word, (e.g., nosedive after studying nosebleed and skydive), subjects might adopt a strategy whereby they recall the studied word(s) that gave rise to the familiarity (nosebleed, skydive) and thereby reject the lure. This method of instantiating retrieval success under conditions in which the target word had not been studied offers converging evidence for the claim that anterior-prefrontal cortex (among other regions) demonstrates enhanced activation during retrieval success.

Adolescent↗
PubMed1999

Considerations regarding mass vaccination against typhoid fever as an adjunct to sanitation and public health measures: potential use in an epidemic in Tajikistan.

We report on the ongoing epidemic of typhoid fever in Tajikistan that started in 1996. It has involved more than 24,000 cases to date, and is characterized by multiple point sources, overflow of sewage, contaminated municipal water, and person-to-person spread. Of the Salmonella typhi isolates available for testing in western laboratories, more than 90% are multidrug-resistant (MDR). Most recently, 28 (82%) of 34 isolates are resistant to ciprofloxacin, representing the first reported epidemic of quinolone-resistant typhoid fever. In the past, mass immunization during typhoid fever epidemics has been discouraged. A review of this policy is recommended in light of the alarming emergence of quinolone-resistant strains of S. typhi, the availability of improved vaccines, and the ongoing epidemic in Tajikistan. Mass immunization may be a useful measure for the control of prolonged MDR typhoid fever epidemics, as an adjunct to correction of municipal infrastructure and public health intervention.

Anti-Infective Agents↗
PubMed1997

Use of granulocyte-macrophage colony stimulating factor in the treatment of prolonged haematopoietic dysfunction after chemotherapy alone or chemotherapy plus bone marrow transplantation.

This study evaluates the use of granulocyte-macrophage colony stimulating factor (GM-CSF) in patients with prolonged haematopoietic dysfunction (> 21 days) after using chemotherapy to treat cancer. One hundred and seven patients were identified who had a leucocyte count below 1000 cells/mm3 more than 21 days after start of chemotherapy (81 patients) or after bone marrow transplantation (BMT)(26 patients). There were 66 males and 40 females ranging in age from 4.5 to 82 years. The duration of aplasia was 48 +/- 43 days in the chemotherapy alone group, and 79 +/- 57 days in the post BMT group. Over 80% of the patients had haematologic malignancies and 70% had an infection prior to the start of the cytokine. Patients received 5 micrograms GM-CSF/kg1 body weight daily i.v. or s.c. for 14 +/- 11 days in the chemotherapy group and 20 +/- 26 days in the BMT group. Sixty percent of chemotherapy patients and 58% of BMT patients had a haematological response to treatment (leucocyte count > 2000 cells/mm3. Median times to haematologic recovery were 7 days in the chemotherapy group and 10 days in the BMT group. There was a significant reduction in the number of infections (73% to 28% in the chemotherapy group). Clinical responses in the two groups were 55% and 50%, respectively. No severe, drug-related adverse events were reported and no evidence of stimulation of malignant clones was observed. It is concluded that GM-CSF is effective and well tolerated in patients with prolonged bone marrow dysfunction after chemotherapy or BMT. Although results from an open-label trial must be viewed with caution, this observation confirms the value and safety of GM-CSF therapy in patients with this severe, and often fatal, condition.

Adolescent↗
PubMed1997

Evaluation of 6 weeks treatment of terbinafine in tinea unguium in a double-blind trial comparing 6 and 12 weeks therapy. The Lagos V Study Group.

Terbinafine (Lamisil) has been registered throughout the world for the treatment of finger and toenail onychomycosis. The recommended duration of treatment of toenail onychomycosis based on phase III studies is 12 weeks. This study was designed to determine: (i) if patients in whom the proximal part of the toenails was not affected respond as well after 6 weeks treatment as after 12 weeks treatment; (ii) to identify factors which may allow selection of patients for shorter treatment duration; and (iii) confirm that 6 weeks therapy is sufficient in fingernail mycosis. One hundred and forty-eight patients received 250 mg terbinafine daily for either 6 or 12 weeks in a double-blinded manner, and were allowed until 48 weeks after start of therapy. Cure of the nail infection was defined as negative mycological tests (mycological cure) and progressive growth of normal nail (clinical cure). Mycological cure was recorded in 43 of 72 (59.7%) in the 6-week group and 55 of 76 (72.4%) in the 12-week group. In those who completed the study per protocol in the 6-week group, 34 of 61 (55.7%) were cured mycologically corresponding to 46 of 56 (82.1%) in the 12-week group. The overall clinical and mycological cure rates for the two groups were 28 of 61 (45.9%) and 33 of 56 (58.9%), respectively. In the small number of patients with associated fingernail infection, all were improved and six of eight (75.0%) were cured after a duration of treatment of 6 weeks. A priori risk factors for failure of cure could not be identified in either group. However, shorter duration of disease prior to treatment and no involvement of the big toenail was associated with a trend toward better responses in both groups. It can be concluded from this study that, in toenail mycosis without visible matrix involvement, 6 weeks treatment of terbinafine is generally not sufficient, whereas fingernail infections respond well to this short therapy.

Adult↗
PubMed1996

The effect of granulocyte-macrophage colony stimulating factor (rGM-CSF) on macrophage function in microbial disease.

The haematopoietic growth factor, GM-CSF, has well-documented stimulatory effects on monocyte and macrophage functions. These effects include enhanced proliferation on their progenitor cells, increased endocytosis and metabolism of mature cells, increased function as antigen-presenting cells, and increased inhibition or killing of intracellular fungi, bacteria, protozoa and viruses. The major effect of GM-CSF on monocytes and macrophages is to enhance phagocytic and metabolic functions, including increased synthesis of molecules toxic to microbes, and to release other proinflammatory cytokines. This results in inhibition and/or killing of Candida albicans, Aspergillus, Cryptococcus, Pneumocystis, Leishmania, Mycobacteria, as well as other intracellular pathogens. GM-CSF also enhances the intracellular effectiveness of antiviral and antibacterial drugs. Viral replication may be increased in activated cells, therefore, when GM-CSF is used, a combination with appropriate antiviral drugs is recommended. Several reports in patients of successful management of microbial diseases which depend on macrophage function are now reviewed. These reports support the clinical value of GM-CSF in the management of patients with cancer and chemotherapy related monocyte/macrophage dysfunction and presumed or documented microbial disease.

Animals↗
PubMed1996

Evaluation of tolerability and antibody response after recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) and a single dose of recombinant hepatitis B vaccine.

Recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) has been shown to augment antigen presentation by macrophages and dendritic cells in vitro, and to increase antibody responses to injected antigens in experimental animals. To evaluate the usefulness of rhGM-CSF as a vaccine adjuvant, 108 healthy volunteers were randomly assigned to receive an injection of rhGM-CSF (n = 81) or placebo (control group; n = 27), followed by an injection with recombinant hepatitis B vaccine into the same site. During the study period of 28 days, protective antibody titers to hepatitis surface antigen (anti-HBs10 mIU ml-1) were observed in 11 of 81 subjects receiving rhGM-CSF, but in none of the controls (P = 0.035). Injections were well tolerated. A single i.m. or s.c. injection of 20-40 micrograms of rhGM-CSF significantly enhances antibody responses when given at the same site as recombinant hepatitis B vaccination.

Adjuvants, Immunologic↗
PubMed1996

Single and multiple test repetition priming in implicit memory.

Using a picture naming task, we compared the magnitude of repetition priming after one prior study episode (single test priming) versus multiple prior study presentations (multiple test priming). Pictures were repeated either one, two, or three times, and the interval between tests was either several minutes (blocked test) or one week (spaced test). Priming increased with additional prior presentations (beyond one) in the multiple test format. In addition, single test priming decreased within one hour after initial exposure, with little change from one hour to two weeks. Priming was unaffected by a simultaneous recognition task, suggesting that picture naming is an implicit task relatively immune from explicit memory contamination.

Humans↗
PubMed1995

Present status of the use of cytokines as adjuvants with vaccines to protect against infectious diseases.

Vaccine adjuvants are expected to play an important role in enhancing the immunogenicity of existing and new-generation vaccines against infectious diseases. In particular, adjuvants should direct the immune response in the most appropriate manner--furthering, for example, an expanded B-cell response, a cytotoxic T-cell response, or a T-helper 1 or 2 subset response. While some noncytokine adjuvants have exerted potent effects, their modes of action are most likely mediated by cytokines. Several cytokines have already been shown to be efficient adjuvants in animal models and/or in clinical trials. The mechanisms of cytokine function must be better understood and the techniques for the use of cytokines improved if the full potential of these substances as vaccine adjuvants is to be realized. When used to best advantage, such adjuvants enhance the immunity induced by viral, bacterial, and parasitic vaccines and thereby promote efficient protection or even cure.

Adjuvants, Immunologic↗
PubMed1995

Overview of the use of terbinafine (Lamisil) in children.

This review summarizes the efficacy and tolerability of terbinafine (Lamisil) in the treatment of dermatophytoses in children. In six clinical studies, 152 children who received terbinafine were evaluable for efficacy and 196 were evaluable for tolerability. In these studies, terbinafine was used for between 1 and 28 weeks. The median treatment was 4 weeks, the duration of treatment in the tinea capitis studies. As a result of extensive experience in adults at doses of 10 mg/kg and less, and the overall pharmacokinetic profile in children, including the lower volume of distribution of terbinafine into lipophilic tissue, the use of a dose of 125 mg/day for children weighing 20-40 kg, and 62.5 mg/day in children weighing less than 20 kg, has been proposed. This dose was shown to be well tolerated and effective. For children weighing > 40 kg, the adult dose of 250 mg is appropriate. Terbinafine was shown to be very effective (93% cured), in the treatment of children with tinea capitis, using a shorter treatment duration (4 weeks) than that usually employed with presently available antifungal drugs. It is also effective in children with various dermatophyte infections of the skin, with a cure rate of more than 90%. Terbinafine was shown to be well tolerated in children aged between 2 and 17 years. The recommended duration of treatment for tinea capitis is 4 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗