Post-translation modification of proteins; methodologies and applications in plant sciences

Proteins have the potential to undergo a variety of post-translational modifications and the different methods available to study these cellular processes has advanced rapidly with the continuing development of proteomic technologies. In this review we aim to detail five major post-translational modifications (phosphorylation, glycosylaion, lipid modification, ubiquitination and redox-related modifications), elaborate on the techniques that have been developed for their analysis and briefly discuss the study of these modifications in selected areas of plant science.

Online immobilized metal affinity chromatography/mass spectrometric analysis of changes elicited by cCMP in the murine brain phosphoproteome

An automated online immobilized metal affinity chromatography/high-performance liquid chromatography mass spectrometric (IMAC-HPLC/MS/MS) method was developed to study cytidine 3',5'-cyclic monophosphate (cCMP)-specific protein phosphorylation, analogous to a previously successful offline IMAC method using microvolume IMAC pipette tips. The optimized method identified murine brain phosphoproteins selectively modified by challenge with cCMP, using manual interpretation of the results to confirm both phosphorylation and selectivity of response to cCMP. A number of proteins identified by this strategy have potential roles in hyperproliferation, a previously reported response to elevated levels of cCMP.

Assessing dopamine concentrations: an evidence-based approach

BACKGROUND: Both overmedication and undermedication can be potentially life threatening. If the actual volume of a 100-mL intravenous bag used to mix dopamine solutions is greater than the labeled volume, overdilution of medication can occur, resulting in an ineffective hemodynamic response in patients and thus an unintended adverse drug event. OBJECTIVES: To determine the actual fluid volumes of 100-mL intravenous bags, compare the actual volumes of 100-mL bags from the 3 major manufacturers of intravenous bags, and determine if the excess volume is sufficient to cause a clinically significant overdilution of dopamine. METHODS: A comparative descriptive design was used. The volumes of 162 intravenous bags of 100 mL of 5% dextrose in water (32 lot numbers with various expiration dates) were measured. Visual volume was confirmed by using a 250-mL graduated cylinder. Volume by weight was determined with a calibrated laboratory-quality electronic scale. On the basis of a mathematical model, any overfill greater than 110 mL was considered clinically significant. RESULTS: The difference between actual and labeled volumes was statistically and clinically significant. Mean visual volume was 110.20 mL (range, 107-114 mL). Mean weighed volume was 109.26 mL (range, 106.15-112.09 mL). The fluid volumes among bags from the 3 major IV companies differed significantly (P < .001). CONCLUSIONS: The overfill in sufficient numbers of 100-mL intravenous bags was enough to cause clinically significant overdilution of dopamine. When dopamine or other vasoactive medications are mixed, either an in-line buret or premixed bags of the drugs should be used to prevent an unintended adverse drug event.

Assessing dopamine concentrations: an evidence-based approach

BACKGROUND

Both overmedication and undermedication can be potentially life threatening. If the actual volume of a 100-mL intravenous bag used to mix dopamine solutions is greater than the labeled volume, overdilution of medication can occur, resulting in an ineffective hemodynamic response in patients and thus an unintended adverse drug event.

OBJECTIVES

To determine the actual fluid volumes of 100-mL intravenous bags, compare the actual volumes of 100-mL bags from the 3 major manufacturers of intravenous bags, and determine if the excess volume is sufficient to cause a clinically significant overdilution of dopamine.

METHODS

A comparative descriptive design was used. The volumes of 162 intravenous bags of 100 mL of 5% dextrose in water (32 lot numbers with various expiration dates) were measured. Visual volume was confirmed by using a 250-mL graduated cylinder. Volume by weight was determined with a calibrated laboratory-quality electronic scale. On the basis of a mathematical model, any overfill greater than 110 mL was considered clinically significant.

RESULTS

The difference between actual and labeled volumes was statistically and clinically significant. Mean visual volume was 110.20 mL (range, 107-114 mL). Mean weighed volume was 109.26 mL (range, 106.15-112.09 mL). The fluid volumes among bags from the 3 major IV companies differed significantly (P < .001).

CONCLUSIONS

The overfill in sufficient numbers of 100-mL intravenous bags was enough to cause clinically significant overdilution of dopamine. When dopamine or other vasoactive medications are mixed, either an in-line buret or premixed bags of the drugs should be used to prevent an unintended adverse drug event.

Serum levels of several organochlorine pesticides in farmers correspond with dietary exposure and local use history

In response to reported increased cancer risks among farmers, the Agricultural Health Study (AHS) was designed to examine health outcomes and environmental exposures among farm families in the United States. In the pilot phase of the AHS, food, beverage, air, dermal, dust, surface wipe, and biological specimens (blood and urine) were collected and analyzed for six farm families in two states (IA and NC). In addition, questionnaires were administered to examine previous pesticide use. This paper reports the organochlorine pesticide results of the serum and dietary analyses as well as questionnaire results from the pilot exposure study of farmers and their families. Note, no organochlorine pesticides were reported as currently being applied to the study farms. In all human serum samples examined, typical U.S. population levels were found for the majority of the pesticides. In addition, human serum levels of organochlorine pesticides showed no significant daily or seasonal variation. However, serum trans-nonachlor levels were found to be higher in people living on the two farms in North Carolina than in people living on the four farms in Iowa (p < 0.05). Further, unusually high dieldrin levels were found in serum samples from a farmer and spouse living on an Iowa farm, and these levels were significantly higher than those of people living on the other farms (p < 0.05). Dieldrin was persistent in the foods consumed on the same Iowa farm where family members showed elevated serum levels. In addition, dietary samples from the North Carolina farms exhibited high levels of chlordane. No organochlorine pesticides were found in any of the drinking water samples. Dietary dieldrin levels on the same Iowa farm exceeded the oral reference dose (RfD) eight- to eleven-fold (50 ng/kg-day). No other pesticide exceeded the RfD. However, dietary chlordane levels at a North Carolina farm reached 17% of the RfD. Previous use of aldrin on an Iowa farm corresponded to dieldrin found in the diet and in the serum of the farmer and spouse. Previous reported use of chlordane on the North Carolina farms corresponded with measurable dietary levels of chlordance and higher serum trans-nonachlor levels than the levels in Iowa farm families.

Correlation of environmental carbaryl measurements with serum and urinary 1-naphthol measurements in a farmer applicator and his family

In exposure or risk assessments, both environmental and biological measurements are often used. Environmental measurements are an excellent means for evaluating regulatory compliance, but the models used to estimate body burden from these measurements are complex. Unless all possible routes of exposure (i.e., inhalation, dermal absorption, ingestion) are evaluated, exposure to a toxicant can be underestimated. To circumvent this problem, measurements of the internal dose of a toxicant in blood, serum, urine, or tissues can be used singularly or in combination with environmental data for exposure assessment. In three separate laboratories, carbaryl or its primary metabolite, 1-naphthol, was measured in personal air, dermal samples, blood serum, and urine from farmer applicators and their families. The usefulness of both environmental and biological data has been demonstrated. For the farmer applicator, the environmental levels of carbaryl would have been sufficient to determine that an exposure had occurred. However, biological measurements were necessary to determine the absorbed dose of each member of the applicator's family. In addition, a correlation between serum and urinary 1-naphthol measurements has been shown; therefore, either matrix can be used to accurately evaluate occupational carbaryl exposure.

Quality of life for critical care patients: a concept analysis

Confusion, misunderstanding, and ethical concerns may interfere with patients' choices for appropriate treatment and subsequent quality of life. Such concerns did not originate from recent technological advances but from the ancient Greeks and Romans who honored health more than life, and the early Christians who honored life more than health. These opposing concepts reflect differing notions of quality of life. Determining the quality of life involves personal issues--the cognitive ability to evaluate one's own life; the perception of a satisfactory state of social, emotional, physical, and mental health; and an acceptable feeling of well-being despite physical limitations. In contrast, and often conflict, are objective evaluations of treatment outcomes, morbidity/mortality statistics, cost/benefit analyses, and age studies performed in an attempt to determine quality of life by persons other than the patient.

Quality of life for critical care patients: a concept analysis

Confusion, misunderstanding, and ethical concerns may interfere with patients' choices for appropriate treatment and subsequent quality of life. Such concerns did not originate from recent technological advances but from the ancient Greeks and Romans who honored health more than life, and the early Christians who honored life more than health. These opposing concepts reflect differing notions of quality of life. Determining the quality of life involves personal issues--the cognitive ability to evaluate one's own life; the perception of a satisfactory state of social, emotional, physical, and mental health; and an acceptable feeling of well-being despite physical limitations. In contrast, and often conflict, are objective evaluations of treatment outcomes, morbidity/mortality statistics, cost/benefit analyses, and age studies performed in an attempt to determine quality of life by persons other than the patient.

The Agricultural Health Study

The Agricultural Health Study, a large prospective cohort study has been initiated in North Carolina and Iowa. The objectives of this study are to: 1) identify and quantify cancer risks among men, women, whites, and minorities associated with direct exposure to pesticides and other agricultural agents; 2) evaluate noncancer health risks including neurotoxicity reproductive effects, immunologic effects, nonmalignant respiratory disease, kidney disease, and growth and development among children; 3) evaluate disease risks among spouses and children of farmers that may arise from direct contact with pesticides and agricultural chemicals used in the home lawns and gardens, and from indirect contact, such as spray drift, laundering work clothes, or contaminated food or water; 4) assess current and past occupational and nonoccupational agricultural exposures using periodic interviews and environmental and biologic monitoring; 5) study the relationship between agricultural exposures, biomarkers of exposure, biologic effect, and genetic susceptibility factors relevant to carcinogenesis; and 6) identify and quantify cancer and other disease risks associated with lifestyle factors such as diet, cooking practices, physical activity, smoking and alcohol consumption, and hair dye use. In the first year of a 3-year enrollment period, 26,235 people have been enrolled in the study, including 19,776 registered pesticide applicators and 6,459 spouses of registered farmer applicators. It is estimated that when the total cohort is assembled in 1997 it will include approximately 75,000 adult study subjects. Farmers, the largest group of registered pesticide applicators comprise 77% of the target population enrolled in the study. This experience compares favorably with enrollment rates of previous prospective studies.

Non-occupational exposures to pesticides for residents of two U.S. cities

The Non-Occupational Pesticide Exposure Study, funded by the U.S. Environmental Protection Agency, was designed to assess total human exposures to 32 pesticides and pesticide degradation products in the non-occupational environment; however, the study focused primarily on inhalation exposures. Two sites--Jacksonville, Florida (USA) and Springfield/Chicopee, Massachusetts (USA)--were studied during three seasons: Summer 1986 (Jacksonville only), Spring 1987, and Winter 1988. Probability samples of 49 to 72 persons participated in individual site/seasons. The primary environmental monitoring consisted of 24-hr indoor, personal, and outdoor air samples analyzed by gas chromatography/mass spectrometry and gas chromatography/electron capture detection. Indoor and personal air concentrations tended to be higher in Jacksonville than in Springfield/Chicopee. Concentrations tended to be highest in summer, lower in spring, and lowest in winter. Indoor and personal air concentrations were generally comparable and were usually much higher than outdoor air concentrations. Inhalation exposure exceeded dietary exposure for cyclodiene termiticides and for pesticides used mainly in the home. Dietary exposures were greater for many of the other pesticides. Inhalation risks were uncertain for termiticides (depending on rates of degradation) but were negligible for other pesticides. The data were insufficient to support risk assessments for food, dermal contact, or house dust exposures.

Scoring acuity hours and costs of nursing for trauma care

OBJECTIVE: To determine nursing resource utilization (acuity hours and dollars) by trauma patients based on analysis of a nursing acuity system and five trauma scoring systems. METHODS: Retrospective review of 448 trauma patients who required transport by aircraft to a level I trauma center. Values from the institution's automated nursing acuity system were compared with the Glasgow Coma Scale score, trauma score, revised trauma score, CRAMS score and injury severity score to obtain acuity hours and financial cost of care for trauma patients. RESULTS: Consistently, analysis of scores computed by five scoring instruments confirmed that nursing resource utilization is greatest for patients who are severely injured but likely to recover. For example, patients with a trauma score of 1 required 49 (+/- 66) mean acuity hours of care; those with a trauma score of 8 needed 189 (+/- 229) mean acuity hours; and those with a trauma score of 16 used 73 (+/- 120) mean acuity hours. Mean dollar costs were $980 (+/- 1293), $3812 (+/- 4518) and $1492 (+/- 2473), respectively. CONCLUSIONS: Nursing resource utilization can be determined for trauma patients by using an automated nursing acuity system and trauma scoring systems. Data acquired in this way provide a concrete basis for healthcare and reimbursement reform, for administrators who design nursing allocations and for nursing educators who prepare graduates to meet the needs of healthcare consumers.

Scoring acuity hours and costs of nursing for trauma care

OBJECTIVE

To determine nursing resource utilization (acuity hours and dollars) by trauma patients based on analysis of a nursing acuity system and five trauma scoring systems.

METHODS

Retrospective review of 448 trauma patients who required transport by aircraft to a level I trauma center. Values from the institution's automated nursing acuity system were compared with the Glasgow Coma Scale score, trauma score, revised trauma score, CRAMS score and injury severity score to obtain acuity hours and financial cost of care for trauma patients.

RESULTS

Consistently, analysis of scores computed by five scoring instruments confirmed that nursing resource utilization is greatest for patients who are severely injured but likely to recover. For example, patients with a trauma score of 1 required 49 (+/- 66) mean acuity hours of care; those with a trauma score of 8 needed 189 (+/- 229) mean acuity hours; and those with a trauma score of 16 used 73 (+/- 120) mean acuity hours. Mean dollar costs were $980 (+/- 1293), $3812 (+/- 4518) and $1492 (+/- 2473), respectively.

CONCLUSIONS

Nursing resource utilization can be determined for trauma patients by using an automated nursing acuity system and trauma scoring systems. Data acquired in this way provide a concrete basis for healthcare and reimbursement reform, for administrators who design nursing allocations and for nursing educators who prepare graduates to meet the needs of healthcare consumers.

Analytical methods for detection of nonoccupational exposure to pesticides

An analytical protocol is developed to analyze for 33 compounds in ambient air around the household, drinking water, and from dermal contact while applying pesticides. Soxhlet extraction is used on both the polyurethane foam plugs, which were used as air sample trapping media, and the gloves reflecting dermal contact. The extraction procedure of U.S. Environmental Protection Agency (EPA) Method 608 is used for water samples. A stringent gas chromatography/electron capture detection (GC/ECD) and gas chromatography/mass spectroscopy/multiple ion detection (GC/MS/MID) analytical approach parallel to the procedures of the current EPA contract laboratory program is used for analysis.

Measurement of atmospheric concentrations of common household pesticides: A pilot study

Air concentrations of 28 of the most commonly used household pesticides were measured inside nine homes in Jacksonville, Florida, and compared with corresponding outdoor levels. The households selected were sorted into three categories according to the degree of pesticide indoor usage. Personal air monitoring was also performed on one resident of each household by means of a portable sampler, which was kept with the person at all times. Five of the pesticides were found in the air inside of the majority of the homes at concentrations as high as 15 μgm(-3) (average concentrations, 12 ngm(-3) to 2.4 μgm(-3)). Indoor levels were generally one to two ordrrs of magnitude higher than surrounding outdoor air levels and personal air measurements were within ± 50% of corresponding indoor values. All samples were collected over 24-hr periods on polyurethane foam and analyzed by capillary colum gas chromatography with mass spectrometric and/or electron capture detection.