Search PubMed⌕ Search

Biomedical subjects

D D Wilson

Publications and source records attributed to D D Wilson.

At least 19 recordsLinked to original sources

Eradication and surveillance of the tropical bont tick in the Caribbean. An international approach.

The Caribbean Amblyomma program (CAP) is a multidonor funded effort involving several technical organizations and national governments in the eradication of the tropical bont tick. The Food and Agriculture Organization (FAO) is the lead technical agency, providing both technical and administrative support to the CAP Regional Coordination Unit (RCU) based in Barbados. All collaborating agencies, donors, and national representatives are members of the Amblyomma Program Council (APC), the overall governing body of the CAP. In addition to FAO, the other organizations involved are the Caribbean Community (CARICOM), the European Union (EU), the Inter-American Institute for Cooperation on Agriculture (IICA), the International Fund for Agricultural Development (IFAD), and the United States Department of Agriculture (USDA). Several agencies (EU, FAO, IFAD, and USDA) are also major donors. The CAP cooperates with the complementary Plan POSEIDOM Veterinaire Program in the French West Indies. The University of the West Indies (UWI), the International Institute for Biological Control (IIBC), and the Departement d'Elevage et de Medecine Veterinaire des Pays Tropicaux (EM-VT) in Guadeloupe are other collaborators.

Agriculture↗

Past and present national tick control programs. Why they succeed or fail.

The historical reasons for the introduction of tick control during the nineteenth century are reviewed. Background and concepts for the choice between long-term tick control and tick eradication are compared. Case studies of large-scale tick control or eradication programs in Africa, Australia, the United States, and the Caribbean are used to highlight successes and failures. The main reasons for lack of sustainability, or failure, of programs are discussed. These include the economic constraints that were faced in several African countries, or technical shortcomings such as were perceived as a major problem in Puerto Rico. The successes are generally associated with enforcement of appropriate legislation and good management, such as occurred in Zimbabwe. These case studies are analyzed to identify features that may assist in the implementation of the ongoing tropical bont tick eradication program in the Caribbean. The paper concludes with some practical suggestions for the future, and the need to reassess the economics of control and the potential additional animal health benefits derived from tick control programs.

Animal Husbandry↗

The CARICOM/FAO/IICA Caribbean Amblyomma Program.

The objective of the Caribbean Amblyomma Program is to eradicate the tropical bont tick (TBT), Amblyomma variegatum, from the Caribbean. Field activities directed to eradication of the TBT were initiated in May 1995 commencing in northern Caribbean islands. Plans have been finalized for the remaining islands to the south to start eradication activities in early 1997. The components of the program include tick control and surveillance, adaptive research, training, communications, and extension. Despite uncertain financial support, substantial progress has been made so far with strong participation by farmers and livestock owners who have been made responsible for the compulsory treatment of all ruminant livestock.

Animal Husbandry↗

Primary lymphoma of the male urethra.

An elderly man presented with urinary outflow obstruction and a smooth mass arising from the bulbar urethra. Biopsy revealed large cell lymphoma, B cell subtype. A literature review revealed no previous cases of undisseminated lymphoma arising within the male urethra. The obstructing mass and symptoms resolved with multiagent chemotherapy.

Aged↗

Progress towards a program for the eradication of Amblyomma variegatum from the Caribbean.

Amblyomma variegatum (Fabricius), the tropical bont tick, is now widely distributed in the Caribbean. Eighteen islands countries are now or were recently infested with the tick. To stop the spread of this tick to other non-infested islands and to the mainland areas of South, Central and North America, a regional eradication program has been proposed and endorsed by the respective governments on each of the Amblyomma variegatum infested islands, including the French government and CARICOM member and associate member countries. The Food and Agriculture Organization of the United Nations (FAO) was requested by CARICOM, on behalf of member and associate member governments to: develop eradication proposals; assist CARICOM member countries to maintain existing Amblyomma tick control programs; advise and assist with the drafting of legislation required for implementation of an eradication program; assist in the identification of funds to implement the eradication program and, if funding was obtained, coordinate the eradication campaign against this tick on all infested islands. The current distribution of the tick and the status of the proposed eradication program in the Caribbean are discussed.

Animals↗

D-Arg-[Hyp3-D-Phe7]-bradykinin, a bradykinin antagonist, reduces mortality in a rat model of endotoxic shock.

The kallikrein-kinin system is activated during endotoxic shock, suggesting that bradykinin plays a role in the pathology of this disease. To test this hypothesis, a bradykinin antagonist, D-Arg-Hyp3-D-Phe7-bradykinin (NPC 567), was studied in conscious, chronically catheterized rats undergoing lipopolysaccharide (LPS)-induced endotoxic shock. LPS treatment resulted in an increase in circulating bradykinin from less than 23 pg/ml to 144 +/- 18 pg/ml at 1 hr. Intravenous administration of LPS resulted in a 38% drop in mean arterial pressure at 1 hr which was partially reversed by NPC 567. NPC 567 did not affect the moderate tachycardia observed following LPS. NPC 567 infusion at 8 nmol/kg/min dramatically reduced mortality from 100% to 50% at 24 hr (P less than 0.01). In response to LPS, blood thromboxane B2 (TXB2) rose from less than 200 pg/ml to 2,298 +/- 64 pg/ml, while 6-keto-prostaglandin-F1 alpha (6kPGF1 alpha) rose from 289 +/- 23 pg/ml to 7,927 +/- 822 pg/ml. NPC 567 reduced the rise in 6kPGF1 alpha by 42% (P less than 0.05), without affecting TXB2. In summary, NPC 567 reduced mortality in rats treated with LPS, reduced the rise in 6kPGF1 alpha and partially reversed the hypotensive effects. These results suggest that bradykinin plays a significant role in the pathology of endotoxic shock.

Analgesics↗

Survey for potential soft tick (Acari: Argasidae) vectors of African swine fever on the island of Hispaniola.

A survey of the occurrence of Ornithodoros ticks in animal burrows was conducted in Haiti and the Dominican Republic. Vacuum sampling techniques were used. Four of 8 sample sites in Haiti and 10 of 70 sample sites in the Dominican Republic were positive for O. puertoricensis Fox. Positive sample sites in Haiti were usually near swine. Sites in the Dominican Republic were in drier regions of the country and were not directly associated with previous swine locations. The determination that O. puertoricensis, a potential vector and reservoir of African swine fever (ASF), is present in this region may pose a serious problem for eradication of ASF from the island of Hispaniola.

African Swine Fever↗

Mortality of Culicoides brevitarsis fed on cattle treated with ivermectin.

Adult female Culicoides brevitarsis Kieffer, important vectors of arboviruses affecting livestock in Australia, were fed on penned Hereford yearling cattle which had been given a single subcutaneous injection of ivermectin at a dose of 200 mcg/kg. The mean mortality of engorged females 48 hr after feeding on the treated cattle was 99% for 10 days posttreatment and in excess of 40% for 18 days posttreatment. Based on these results, it appears that ivermectin administered subcutaneously could be a useful tool for the control of Culicoides-transmitted diseases and would provide an attractive alternative to "slaughter out" programs in the case of a major exotic disease threat.

Animals↗

Craniopharyngioma intrinsic to the third ventricle.

The case of a third ventricular craniopharyngioma in a 57-year-old woman is reported. This lesion is rare, having been previously identified in only eight adults. Intraventricular craniopharyngioma is also unusual in that it is not associated with tumoral calcification or cyst formation, as is frequently seen with the more common suprasellar craniopharyngioma. The role of computed tomography scanning in the diagnosis of this tumor is presented and discussed.

Adult↗

Validation of viscosity measurements for canine hepatic bile.

This study developed the validated standards for a known viscosity method by obtaining consistent viscosity measurements with defined precision, reproducibility and sensitivity limits for canine hepatic bile. Size 75 Cannon-Manning semimicro viscometers yielded the most precise viscosity measurements. With the development of proper handling methods for fresh bile samples, a precision defined by a coefficient of variation of less than or equal to +/- 0.3% was obtained. To maintain viscometer constancy, the viscometers must be cleaned with chromic acid after each bile test and pass reproducibility tests using defined distilled water viscosity tests.

Animals↗

Bladder pheochromocytoma with ring calcification.

A case of a 19-year-old male with a paraganglioma (pheochromocytoma) arising in the prostate and involving the urinary bladder is presented. The radiological studies, including computed tomography, demonstrated ringlike calcification of the tumor, a rare finding that is highly suggestive of the diagnosis of pheochromocytoma. The tumor was excised and found to be malignant at surgery.

Adult↗