Search PubMed⌕ Search

Biomedical subjects

James W Jones

Publications and source records attributed to James W Jones.

At least 37 records · Page 2Linked to original sources
PubMed2005

Withdrawal of life-sustaining low-burden care.

A 90-year-old diabetic man with unreconstructable peripheral vascular disease, end-stage chronic obstructive pulmonary disease, relentless ischemic rest pain, and severe disability returns to your clinic asking you to deactivate his implanted pacemaker. To do so would likely precipitate his demise, and you ask him if he is aware of this. He tells you that he is and that he has been considering this request since he last saw you 3 months ago. Relief of his chronic pain would require bilateral hip-disarticulating amputations, procedures with a prohibitively high operative mortality rate, particularly with his age and comorbidities. He has been evaluated by a psychiatrist and found to be mentally competent. His treatment by a pain specialist, who used his full armamentarium of high-dose narcotics, electronic devices, nerve blocks, and psychological techniques, has been unsuccessful. You do not reside in Oregon. What is your most ethical course of action?

Aged↗
PubMed2005

Turf wars: the ethics of professional territorialism.

A 300-bed general hospital in a mid-sized city has a busy cardiac catheterization laboratory, with 12 invasive cardiologists and more than 4000 annual procedures. An invasive radiology suite, the only one in town, is staffed by a single invasive radiologist and two vascular surgeons. They perform about 150 diagnostic angiograms and endovascular procedures each year, about half of which are generated by consultation requests from the cardiologists. The invasive radiology team has worked together for the last 5 years, since an endovascular fellowship-trained vascular surgeon joined the staff. The invasive radiologist helped to develop an endovascular team and mentored the more senior vascular surgeon until he could accumulate the requisite number of procedures to become credentialed. The program's finances and work schedule have been arranged to the satisfaction of all three participants. Until recently, whenever cardiologists found evidence of vascular occlusive disease during catheterizations, they changed host arteries; if symptoms and signs indicated a need for therapy, they referred patients to the invasive radiology clinic. Lately, the cardiologists have begun to perform terminal angiograms on all their patients to detect injuries. They have requested clinical privileges to perform peripheral endovascular procedures as well as traditional cardiac work. The hospital administrator is fearful that the cardiologists may leave the hospital if their request is denied. The invasive radiology staff are concerned that the caseload is insufficient to maintain quality if they must divide it with the cardiologists. You are the hospital Chief of Staff and must decide whether to grant the cardiologists privileges which have thus far been reserved to the endovascular team. What should you do?

Cardiology↗
PubMed2005

Whodunit? Ghost surgery and ethical billing.

A senior vascular surgery resident started an autogenous radical-cephalic arteriovenous fistula procedure on a comatose patient in the surgical intensive care unit (SICU), expecting you to arrive momentarily. You were nevertheless unexpectedly detained establishing hemostasis in the main operating suite. You arrived in the SICU as the dressing was being applied. Fistula flows were excellent and there were no operative complications. The resident who began and finally completed the case was highly skilled and in the final month of his vascular training; you had supervised his satisfactory performance of many procedures like this one during the last 2 years. The patient's elderly wife had consented to the procedure, which she was told you would be directly supervising while the resident performed the surgery. When the operation was over you met with her to explain your emergency conflict and assure her that you checked the resident's work and found it entirely satisfactory. She accepted your explanation and was relieved that the operation went well. The patient's multiple comorbidities nevertheless necessitated an extended postoperative stay in the SICU, where you personally cared for him. The resident had dictated routinely that you attended the procedure, and your billing clerk had no reason to doubt the operative report's accuracy when she submitted your surgical fees to Medicare and the patient's private insurer, which paid to their contractual limits without challenge. On many occasions you have had your billings shorted by both. The resident since has graduated. What should you do?

Arteriovenous Shunt, Surgical↗
PubMed2005

Informed consent: it's not just signing a form.

Informed consent plays a major role in forming a therapeutic alliance with the patient. The informed consent process has evolved from simple consent, in which the surgeon needed only to obtain the patient's permission for a procedure, into informed consent, in which the surgeon provides the patient with information about clinically salient features of a procedure, the patient understands this information adequately, and the patient voluntarily authorizes the surgeon to perform the procedure. Special circumstances of informed consent include conflicting professional opinions, consent with multiple physicians, patients who are undecided or refuse surgery, patients with diminished decision-making capacity, surrogate decision making, pediatric assent, and consent for the involvement of trainees.

Communication↗
PubMed2005

Human Infection with Rickettsia honei, Thailand.

Human spotted fever rickettsiosis was detected molecularly by 2 real-time polymerase chain reaction (PCR) assays performed on DNA extracted from a Thai patient's serum sample. Sequences of PCR amplicons from 5 rickettsial genes used for multilocus sequence typing were 100% identical with those deposited with GenBank for Rickettsia honei TT-118.

Adult↗
PubMed2005

Genetic structure of Aedes aegypti populations in Thailand using mitochondrial DNA.

A hierarchical population genetic study was conducted among 19 Aedes aegypti populations in Thailand from Chiang Mai in the north to Songkhla province in the south. Single-strand conformation polymorphism analysis was used to examine variation in a 359-basepair region of the NADH dehydrogenase subunit 4 mitochondrial DNA gene (ND4). Seven haplotypes were detected in two lineages previously identified in ND4 haplotypes from North America. Gene flow estimates and highly significant variation among populations within 25 kilometers implicated genetic drift and vector control efforts as major factors in genetic structure. Mantel regression analysis demonstrated no isolation by distance. Urban areas were relatively panmictic, while suburban/rural sites exhibited more restricted gene flow. Significant genetic structure among groups of collections > 100 kilometers apart is consistent with recent (approximately 50 year) expansion of Ae. aegypti from highly populated areas accompanied by founder effects, but could also reflect the overall low genetic diversity in ND4 in Thailand.

Aedes↗
PubMed2005

Ikonos-derived malaria transmission risk in northwestern Thailand.

We mapped overall malaria cases and located each field observed major malaria vector breeding habitat using Global Positioning System (GPS) instruments from September 2000 to October 2003 around the three malaria-endemic villages of Ban Khun Huay, Ban Pa Dae, and Ban Tham Seau, Mae Sod district, Tak Province, Thailand. The land-use/land-cover classifications of the three villages and surrounding areas were performed on IKONOS satellite images acquired on 12 November 2001 with a spatial resolution of 1 x 1 m. Stream network was delineated and displayed. Proximity analysis was performed on the locations of the houses with and without malaria cases within a 1.5 km buffer from An. minimus immature mosquito breeding habitats, mainly stream margins. The 1.5 km used in our proximity analysis was arbitrarily estimated based on the An. minimus flight range. A statistical t-test at 5% significance level was performed to evaluate whether houses with malaria cases have higher proximities to streams than houses without malaria cases. The result shows no significant difference between proximity to streams between houses with malaria cases and houses without malaria cases. We suspect that the actual flight range of An. minimus may be greater than 1.5 km. The An. minimus larval habitat deserves more detailed investigation. Further studies on human behavior contrary to that required for adequate malaria control among these three villages are also recommended.

Animals↗
PubMed2005

Water quality and breeding habitats of anopheline mosquito in northwestern Thailand.

Malaria transmission is dependent upon many hydrology-driven ecological factors that directly affect the vectorial competence, including the presence of suitable habitats for the development of anopheline larvae. Larval habitats were identified and characterized at three malaria endemic villages (Ban Khun Huay, Ban Pa Dae, and Ban Tham Seau) in Mae Sot district, Tak Province, in northwestern Thailand between July 2002 and June 2003. The Global Positioning System (GPS) was used to provide precise locational data for the spatial distribution of anopheline mosquito larvae and their habitats. Ten habitat categories were identified. Eighteen adult Anopheles species were identified from larvae in all the surveyed habitats. An. minimus was the most common species throughout the year. The relationship between eight abiotic variables (temperature, hardness, carbon dioxide, dissolved oxygen, nitrate, phosphate, silica and pH) and the abundance of four major species of malaria vectors (An. (Cel.) dirus, An. (Cel.) minimus, An. (Cel.) maculatus, and An. (Cel.) sawadwongporni), and six species of non-vectors (An. (Cel.) kochi, An. (Cel.) jamesii, An. (Ano.) peditaeniatus, An. (Ano.) barbirostris, An. (Ano.) campestris, and An (Cel.) vagus) larvae was investigated. The results from the multiple regression models suggest that hardness, water temperature and carbon dioxide are the best predictor variables associated with the abundance of An. minimus larvae (p < 0.001); water pH for An. dirus larvae (p < 0.001); temperature and pH for An. kochi larvae (p < 0.01); temperature and silica concentration for An. jamesii larvae (p < 0.001); dissolved oxygen and silica concentration for An. campestris larvae (p < 0.001); and pH and silica concentration for An. vagus larvae (p < 0.001). We could not identify key environmental variables for An. maculatus, An. sawadwongporni, An. peditaeniatus, and An. barbirostris.

Animals↗
PubMed2005

Bottle and biochemical assays on temephos resistance in Aedes aegypti in Thailand.

The bottle bioassay measuring the time-mortality rate is a simplified procedure for detecting insecticide resistance. It can be used with a biochemical microplate assay to identify the mechanism involved. This integrated approach was used to detect temephos resistance in Aedes aegypti from Nonthaburi (lowest use) and Roi Et (highest use). Ae. aegypti BKK1 laboratory strain was used as the susceptible reference strain. The appropriate concentration of insecticide for bottle bioassay was determined empirically for Ae. aegypti BKK1 strain and found to be in the range of 800-1,050 microg/bottle. The time-mortality rate at 800 microg/bottle was 170 +/- 8.66 minutes, significantly different from the time-mortality rates in the 850, 900, 950, and 1,050 microg/bottle (p = 0.008) concentrations, which were 135 +/- 15.00, 140 +/- 8.66, 135 +/- 15.00, and 125 +/- 8.66 minutes, respectively. The cut-off concentration selected for resistance detection was 850 microg/bottle. The time-mortality rate for the Roi Et strain was 382 +/- 26.41 minutes, significantly higher than the Nonthaburi (150 +/- 25.10 minutes) and BKK1 strains (145 +/- 20.49 minutes) (p < 0.001). The temephos resistance ratio (RR100) for the Ae. aegypti Roi Et strain was 2.64-fold higher at lethal time (LT100) than for the reference Ae. aegypti BKK1 strain. The mean optical density (OD) value from the biochemical microplate assay for the non-specific esterase of the Roi Et strain was higher than the mean OD for the non-specific esterase of both the Nonthaburi and BKK1 strains. Insensitive acetylcholinesterase was not found to be responsible for the resistance in the field-collected mosquitos. This study suggests that esterase detoxification is the primary cause of resistance in the Ae. aegypti population from Roi Et. Both the bottle bioassay and the biochemical microplate assay were proven to be promising tools for initial detection and field surveillance for temephos resistance.

Acetylcholinesterase↗
PubMed2005

Morphological variations of Anopheles minimus A in Tak Province, Thailand.

Anopheles minimus Theobald is one of the major vectors of malaria throughout the Oriental Region, and it's complex consists of at least 2 sibling species (A and C) in Thailand. This study aimed to determine the morphological variations of wings of An. minimus A and to clarify the specific status of An. minimus in Ban Khun Huay, Ban Pa Dae, and Ban Tham Seau, Mae Sot district, Tak Province, Thailand. Anopheline larvae were collected from the fields between October 2002 and September 2003, allowed to emerge into adults in the laboratory and identified by morphological and molecular characterization. About 1,715 of female An. minimus A were separated into 8 groups based on their wing scale patterns. Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP) assay (ribosomal DNA ITS2) confirmed the identification of An. minimus A in all 8 groups.

Animals↗