Carbon footprint of Canadian dairy products: calculations and issues.

The Canadian dairy sector is a major industry with about 1 million cows. This industry emits about 20% of the total greenhouse gas (GHG) emissions from the main livestock sectors (beef, dairy, swine, and poultry). In 2006, the Canadian dairy herd produced about 7.7 Mt of raw milk, resulting in about 4.4 Mt of dairy products (notably 64% fluid milk and 12% cheese). An integrated cradle-to-gate model (field to processing plant) has been developed to estimate the carbon footprint (CF) of 11 Canadian dairy products. The on-farm part of the model is the Unified Livestock Industry and Crop Emissions Estimation System (ULICEES). It considers all GHG emissions associated with livestock production but, for this study, it was run for the dairy sector specifically. Off-farm GHG emissions were estimated using the Canadian Food Carbon Footprint calculator, (cafoo)(2)-milk. It considers GHG emissions from the farm gate to the exit gate of the processing plants. The CF of the raw milk has been found lower in western provinces [0.93 kg of CO2 equivalents (CO2e)/L of milk] than in eastern provinces (1.12 kg of CO2e/L of milk) because of differences in climate conditions and dairy herd management. Most of the CF estimates of dairy products ranged between 1 and 3 kg of CO2e/kg of product. Three products were, however, significantly higher: cheese (5.3 kg of CO2e/kg), butter (7.3 kg of CO2e/kg), and milk powder (10.1 kg of CO2e/kg). The CF results depend on the milk volume needed, the co-product allocation process (based on milk solids content), and the amount of energy used to manufacture each product. The GHG emissions per kilogram of protein ranged from 13 to 40 kg of CO2e. Two products had higher values: cream and sour cream, at 83 and 78 kg of CO2e/kg, respectively. Finally, the highest CF value was for butter, at about 730 kg of CO2e/kg. This extremely high value is due to the fact that the intensity indicator per kilogram of product is high and that butter is almost exclusively fat. Protein content is often used to compare the CF of products; however, this study demonstrates that the use of a common food component is not suitable as a comparison unit in some cases. Functionality has to be considered too, but it might be insufficient for food product labeling because different reporting units (adapted to a specific food product) will be used, and the resulting confusion could lead consumers to lose confidence in such labeling. Therefore, simple units might not be ideal and a more comprehensive approach will likely have to be developed.

Seasonality of brown recluse populations is reflected by numbers of brown recluse envenomations.

A significant seasonal correlation was recently shown for brown recluse spider activity. Vetter (2011) observed brown recluse spiders were submitted by the general public predominantly during April-October. For patients with suspected brown recluse spider bites (BRSB), we have observed the same seasonality. Among 45 cases with features consistent of a BRSB, 43 (95.6%) occurred during April-October. Both the Vetter study and our study serve to demonstrate seasonal activity for brown recluse spiders.

Temporal and seasonal variation in the occurrence of chemical incidents.

AIMS: To determine whether there were temporal or seasonal patterns in the occurrence of chemical incidents reported to the West Midlands Chemical Incident Surveillance System, UK. METHODS: A retrospective analysis of reports maintained on a computerised database was carried out for information received from January 1997 to December 2001. RESULTS: Annual numbers of events increased significantly from 77 (7.5%) in 1997 to 282 (27.4%) in 2001. Compared to the average of other seasons, proportionately more incidents occurred in the summer (29.3%). Compared with the average of other days, incidents were more likely to occur on Thursdays (17.1%) and least likely on Saturdays (8.9%). When grouped together on a six hourly basis incidents were most frequent between 12 00 and 17 59 (31.1%) and least frequent between 00 00 and 05 59 (21.2%). CONCLUSIONS: The surveillance system shows that chemical incidents do not occur randomly but have marked temporal and seasonal variation. These results have implications for service provision, training, and the development of preventive strategies.

Carrier detection and rapid newborn diagnostic test for the common Y393N maple syrup urine disease allele by PCR-RFLP: culturally permissible testing in the Mennonite community.

The turnaround time for diagnosis of maple syrup urine disease (MSUD) by classic serum amino acid analyses often requires 3-4 days. This is due to the need for branched-chain amino acids (BCAA) to accumulate in the serum of the newborn before testing. The accumulation of BCAAs in infants with MSUD during this time increases the risk of the infant becoming clinically symptomatic. We have developed a noninvasive DNA-based mismatch PCR-RFLP assay for the Y393N BCKDHA allele (E1alpha gene of the branched chain alpha-keto acid dehydrogenase complex), the primary cause of MSUD in Old Order Mennonite communities. The homozygosity and high frequency of this mutation in the Mennonite community and its prevalence in compound heterozygote non-Mennonite MSUD patients is of significance. We describe carrier testing, present the results of nine newborns diagnostically evaluated for the Y393N BCKDHA allele, and demonstrate the efficacy of this PCR-RFLP assay for determining clinical status within 24 h after birth. Analyses within the first 24 h of life allow for immediate diagnosis and treatment of infants homozygous for the Y393N MSUD defect. This is a significant improvement over the time required by current serum amino acid analysis methods.

Reducing the progression of myopia with atropine: a long term cohort study of Olmsted County students.

BACKGROUND: Myopia is an important public health problem because it is common and is associated with increased risk for chorioretinal degeneration, retinal detachment, and other vision- threatening abnormalities. In animals, ocular elongation and myopia progression can be lessened with atropine treatment. This study provides information about progression of myopia and atropine therapy for myopia in humans. METHODS: A total of 214 residents of Olmsted County, Minnesota (118 girls and 96 boys, median age, 11 years; range 6 to 15 years) received atropine for myopia from 1967 through 1974. Control subjects were matched by age, sex, refractive error, and date of baseline examination to 194 of those receiving atropine. Duration of treatment with atropine ranged from 18 weeks to 11.5 years (median 3.5 years). RESULTS: Median followup from initial to last refraction in the atropine group (11.7 years) was similar to that in the control group (12.4 years). Photophobia and blurred vision were frequently reported, but no serious adverse effects were associated with atropine therapy. Mean myopia progression during atropine treatment adjusted for age and refractive error (0.05 diopters per year) was significantly less than that among control subjects (0.36 diopters per year)(P<.001). Final refractions standardized to the age of 20 years showed a greater mean level of myopia in the control group (3.78 diopters) than in the atropine group (2.79 diopters) (P<.001). CONCLUSIONS: The data support the view that atropine therapy is associated with decreased progression of myopia and that beneficial effects remain after treatment has been discontinued.

Investigations of the pathway of incorporation and function of lamin A in the nuclear lamina.

Cell-free extracts of Xenopus eggs were used to investigate how differing lamin sub-types are incorporated into a lamina and how lamina composition influences DNA replication. Purified recombinant human lamin A (HlaminA) was inoculated into egg extracts, which support in vitro nuclear assembly. The route of incorporation of Hlamin A into the lamina was compared to Xenopus lamin B3 (XlaminB3), the major endogenous lamin sub-type in egg extracts. While Xlamin B3 was incorporated into the lamina directly, HlaminA first accumulated at nucleoplasmic foci, before entering the lamina. When HlaminA was inoculated into extracts depleted of XlaminB3 it entered nuclei efficiently and was incorporated into nucleoplasmic foci. However, in the absence of XlaminB3, HlaminA remained in the foci and did not enter the nuclear envelope. When HlaminA entered the nuclear envelope, it did not influence DNA replication. Nuclei containing HlaminA initiated DNA replication on queue and in addition the spatial distribution of replication centres in these nuclei was identical to controls. Taken together, these results suggest that the incorporation of A-type lamins into the nuclear envelope is dependent upon the presence of B-type lamins. However, the presence of A-type lamins alone is not sufficient to influence the spatial and temporal order of DNA replication.

Immunization status and sociodemographic characteristics: the mediating role of beliefs, attitudes, and perceived control.

OBJECTIVES: This study examined how immunization-related beliefs, attitudes, and perceived control mediate up-to-date immunization among various sociodemographic groups. METHODS: Statewide estimates of immunization rates among children up to the age of 2 years were obtained via a multistage cluster sample. In-person interviews were conducted with 4832 parents. Information about immunization was obtained from official records or from health care providers. RESULTS: Differences in immunization among sociodemographic groups were mediated by beliefs about objective barriers to immunization, protection, medical contraindication, safety concerns, distrust, and natural immunity. Protection beliefs contributed to positive attitudes toward immunization; beliefs in natural immunity and safety concerns contributed to negative attitudes. Beliefs about objective barriers, distrust, safety concerns, and medical contraindications influenced perceived control over immunization. Positive attitudes and a strong sense of control contributed to higher immunization rates. CONCLUSION: These findings provide a basis for efficient educational campaigns by specifying which beliefs should be bolstered (because they facilitate proper immunization) and which should be targeted for change (because they hinder proper immunization) in various sociodemographic groups.

When acculturation hurts: the case of immunization.

The study examined the relationship between the acculturation of Mexican American mothers in Texas and immunization status of their children between 3 and 24 months of age. Mothers' acculturation, demographic characteristics, and immunization status of their children were assessed in in-person interviews with a sample of Mexican American respondents representative for Texas (n = 2193). Acculturation was measured with ten scales assessing oral and written language use, proficiency, and preference, music and TV viewing preferences, ethnic identity, place where a person was reared, and contacts with Mexico. Immunization status, defined according to the recommendation of the CDC Advisory Committee on Immunization Practices, was determined from official shot records obtained directly from respondents or, for respondents without records, obtained from their health care providers. Regression analysis revealed that acculturation significantly contributed to inadequate immunization status, even when socioeconomic status and other demographic covariates of acculturation were statistically controlled. Mediational analysis revealed that acculturation contributed to inadequate immunization through less positive attitudes toward immunization, a diminished sense of parental responsibility for children's immunization, and more perceived barriers to immunization. It is concluded that culture-specific beliefs encouraging childhood immunization should be fostered among Mexican Americans.

Cell cycle changes in A-type lamin associations detected in human dermal fibroblasts using monoclonal antibodies.

A new panel of anti-A-type lamin monoclonal antibodies was generated. Epitope mapping was performed by immunoblotting against GST-lamin fusion peptides. Epitopes were mapped to four different regions of human lamin A and three different regions of human lamin C. The distribution of A-type lamins was compared with the distribution of the proliferation marker Ki67 in proliferating and quiescent cultures of human dermal fibroblasts (HDFs) using a double indirect immunofluorescence assay. Antibodies that had been mapped to a region of the lamin C tail stained the nuclear envelope of proliferating and quiescent cells equally brightly. In contrast, antibodies recognizing epitopes in the head domain and rod domain of lamins A and C and the tail domain of lamin A stained the nuclear envelope of quiescent cells strongly but reacted poorly or not at all with the nuclear envelope of proliferating cells. Changes in the level of expression of lamins A and C were not detected in immunoblotting assays. However, epitope masking was revealed, and this occurred by two distinct mechanisms. Epitope masking in the head domain of lamins A and C occurred as a result of protein phosphorylation. Epitope masking in the rod domain of lamins A and C and in the tail domain of lamin A occurred through a physical association between the lamin and chromatin and/or other nuclear proteins. The cell cycle timing of epitope masking was investigated in HDFs that had been restimulated after serum starvation. Extensive epitope masking in restimulated cells only occurred after cells had passed through mitosis. These results are consistent with the hypothesis that rearrangement of A-type lamin filaments, as cells progress from a quiescent to a proliferating state, results in altered lamina associations.

Selenoprotein gene expression during selenium-repletion of selenium-deficient rats.

Selenium repletion of selenium-deficient rats with 20 micrograms selenium / kg body weight as Na2SeO3 was used as a model to investigate the mechanisms that control the distribution of the trace element to specific selenoproteins in liver and thyroid. Cytosolic glutathione peroxidase (cGSHPx), phospholipid hydroperoxide glutathione peroxidase (PHGSHPx), and iodothyronine 5'-deiodinase (IDI) activities were all transiently increased in liver 16 to 32 h after ip injection with selenium. However, only cGSHPx and PHGSHPx activities increased in the thyroid where IDI activity was already increased by selenium deficiency. These responses were owing to synthesis of the seleoproteins on newly synthesised and/or existing mRNAs. The selenoprotein mRNAs in the thyroid gland were increased two- and threefold after the transitory increases in selenoprotein activity. In contrast, there were parallel changes in selenoprotein mRNAs and enzyme activities in the liver, with no prolonged rises in mRNA levels. The organ differences suggest that increased thryotrophin (TSH) concentrations, which are known to induce thyrodial IDI and mRNA, may control the mRNAs for all the thyroidal selenoproteins investigated and be a major mechanism for the preservation of thyroidal selenoproteins when selenium supplies are limited.

Visual problems of the aging musician.

The presbyopic musician presents the ophthalmologist with an often demanding set of visual needs. Many modalities, some necessarily creative, are available to aid older musicians in their vision-dependent art.

Tissue-specific regulation of selenoenzyme gene expression during selenium deficiency in rats.

Regulation of synthesis of the selenoenzymes cytosolic glutathione peroxidase (GSH-Px), phospholipid hydroperoxide glutathione peroxidase (PHGSH-Px) and type-1 iodothyronine 5'-deiodinase (5'IDI) was investigated in liver, thyroid and heart of rats fed on diets containing 0.405, 0.104 (Se-adequate), 0.052, 0.024 or 0.003 mg of Se/kg. Severe Se deficiency (0.003 mg of Se/kg) caused almost total loss of GSH-Px activity and mRNA in liver and heart. 5'IDI activity decreased by 95% in liver and its mRNA by 50%; in the thyroid, activity increased by 15% and mRNA by 95%. PHGSH-Px activity was reduced by 75% in the liver and 60% in the heart but mRNA levels were unchanged; in the thyroid, PHGSH-Px activity was unaffected by Se depletion but its mRNA increased by 52%. Thus there is differential regulation of the three mRNAs and subsequent protein synthesis within and between organs, suggesting both that mechanisms exist to channel Se for synthesis of a particular enzyme and that there is tissue-specific regulation of selenoenzyme mRNAs. During Se depletion, the levels of selenoenzyme mRNA did not necessarily parallel the changes in enzyme activity, suggesting a distinct mechanism for regulating mRNA levels. Nuclear run-off assays with isolated liver nuclei showed severe Se deficiency to have no effect on transcription of the three genes, suggesting that there is post-transcriptional control of the three selenoenzymes, probably involving regulation of mRNA stability.

Environmental considerations of disinfectants used in agriculture.

Using disinfectants in agriculture increasingly requires consideration of the indirect effects on the environment and human health. At present, only limited information is available on post-application effects of disinfectants, and such data therefore needs to be gathered in order to assess potential effects. In addition, a basis exists for establishing precautionary guidelines using current information. Optimum handling and application procedures require a knowledge of the specific features of each type of disinfectant. A need to establish product standards through efficacy tests has also emerged. The benefits of disinfectants for disease control must also be weighed against any environmental consequences. Emergency application of a disinfectant carries different implications from routine use on farms, and any large-scale application should undergo an environmental impact assessment.

Lack of global vagal propensity in patients with oculocardiac reflex.

BACKGROUND: Profound bradycardia during ophthalmic surgery is a rare but potentially serious event. Little is known about the predictability of the oculocardiac reflex. METHODS: Four vagotonic maneuvers were performed on six patients who had profound oculocardiac reflex (3- to 10-second asystole) during eye surgery, the results of which were compared with 30 previously studied control subjects. Electrocardiographs were monitored during the following vagotonic maneuvers: diving response (apneic facial immersion), Valsalva maneuver, ocular compression, and carotid sinus massage. RESULTS: The degree of heart rate slowing as a result of diving response, Valsalva maneuver, and, notably, ocular compression did not differ when these patients were compared with the 30 previously studied control subjects. Carotid sinus massage produced significantly (P = 0.01) more bradycardia in the six patients (mean +/- standard deviation, -24% +/- 6%) than in the 30 control subjects (-12% +/- 7%). The heart rate response to pressure on the eyes did not correlate with prior intraoperative oculocardiac reflex. CONCLUSION: The discrepancy in heart rate sensitivity between surgical extraocular muscle tension and ocular compression may be due to different sensory receptors and brain stem processing for the trigeminally mediated oculocardiac reflex. Carotid sinus massage may help predict low heart rates during eye surgery.

The high-monounsaturated fat diet as a practical alternative for NIDDM.

OBJECTIVE: To examine the dietary preferences of and metabolic effects in patients with non-insulin-dependent diabetes mellitus (NIDDM) of a home-prepared high-monounsaturated fat (HM) diet compared with the recommended high-carbohydrate (CHO) diet. RESEARCH DESIGN AND METHODS: Ten men with mild NIDDM prepared HM and high-CHO diets at home alternately and in random order for 2 weeks each with a minimum 1-week washout. Before and after each diet, 24-h urine glucose, fasting lipids, fructosamine, and 6-h profiles of glucose, insulin, and triglycerides were measured. Dietary preferences were assessed by questionnaire. RESULTS: In the HM diet, patients consumed 40% of energy intake as CHO and 38% as fat (21% monounsaturated) compared with 52 and 24%, respectively, in the high-CHO diet, with equal dietary fiber content. Body weight and total energy intake were similar in both. The HM diet resulted in significantly lower 24-h urinary glucose excretion, fasting triglyceride, and mean profile glucose levels. The fructosamine levels, the fasting total, low-density lipoprotein, and high-density lipoprotein cholesterol, and the prandial triglyceride concentrations did not differ significantly as a result of the diets. The two diets did not differ in ratings for overall acceptance, taste, cost, ease of preparation, variety, or satiety. CONCLUSIONS: Prepared at home, the HM diet was, in the short-term, metabolically better in some aspects than the currently recommended diet for NIDDM. It also provided a palatable alternative.

Ocular complications in renal transplant patients.

One hundred and seventy-six patients who received a renal transplant between 1982 and 1988 were examined for ocular complications of steroid therapy. Posterior subcapsular cataracts (PSC) were present in 60 patients (34.1%). Patients were classified into three groups (HS, LS, NoS) depending on their maintenance immunosuppression therapy. The HS group received high doses of steroids after renal transplantation. LS had low steroid doses, and NoS had no steroids. The incidence of PSC was 21 of 38 in HS (55.3%), 33 of 117 in LS (28.2%), and 1 of 16 in NoS (6.2%). The difference between HS and LS was statistically significant (chi 2 = 8.1, P < 0.01). Grading the severity of PSC (PSC 0, PSC +, PSC > ++) showed a significant correlation between the degree of PSC and the steroid therapy. In the HS group, five patients had PSC +, and 16 had PSC > ++ (76%), compared to 19 patients with PSC +, 14 patients with PSC > ++ (42%) in the LS group (chi 2 = 4.6; P < 0.05). There was no correlation between the incidence of PSC and use of steroids for more than three months before dialysis. Comparison with the results of our earlier series (1973-1981) using high doses of steroids showed a similar incidence of PSC with HS (40.7% Series 1; 55.3% Series 2) but a lower incidence with LS and NoS.

Phospholipid hydroperoxide glutathione peroxidase: full-length pig blastocyst cDNA sequence and regulation by selenium status.

We have isolated and sequenced an apparent full-length cDNA clone for phospholipid hydroperoxide glutathione peroxidase (Genbank accession number L12743) from a pig blastocyst cDNA library. The sequence encodes a polypeptide of 170 amino acids, including a TGA-encoded selenocysteine at residue 46, with a calculated M(r) of 19,492 Da. Use of this clone in Northern blot analysis of Se-deficient rat liver revealed that phospholipid hydroperoxide glutathione peroxidase mRNA levels were little affected by Se deficiency, whereas classical glutathione peroxidase mRNA levels were decreased by 90% in the same samples. Lastly, liver phospholipid hydroperoxide glutathione peroxidase mRNA levels were not elevated in female rats, in contrast to classical glutathione peroxidase.