Golde I. Holtzman

Retrospective evaluation of urinary tract infection in 42 dogs with hyperadrenocorticism or diabetes mellitus or both.

A retrospective study was performed to determine the proportion of dogs with hyperadrenocorticism or diabetes mellitus or both that had urinary tract infection (UTI) and to describe clinical and laboratory findings. Dogs with these endocrine disorders were included if results of quantitative urine culture were available and dogs were not receiving antimicrobials. Dogs with positive urine cultures were considered to have UTI and dogs with negative urine cultures were used as controls. Information including history, clinical signs, physical examination findings, and results of laboratory tests and urine culture was extracted from all records. Findings in dogs with UTI were compared with control dogs. There were 101 dogs with hyperadrenocorticism or diabetes mellitus or both that met inclusion criteria; 42 (41.6%) had UTI and 59 (58.4%) did not. UTI was present in 46% of dogs with hyperadrenocorticism, 37% of dogs with diabetes mellitus, and 50% of dogs with both endocrine disorders. There was no association between endocrine group and occurrence of UTI. Escherichia coli was the most common bacteria isolated, and cultures from 29 dogs (69%) showed growth of this organism. Of dogs with UTI, <5% had stranguria, pollakiuria, or discolored urine, whereas 60% had pyuria and 69% had bacteriuria. We conclude that UTIs are common in dogs with hyperadrenocorticism, diabetes mellitus, or both diseases. Clinical signs of UTI, however, are uncommon and results of urinalysis may be normal. Therefore, it is appropriate to recommend urine culture as part of the evaluation of dogs with these endocrine disorders.

The effects of peripheral vascular disease with osteomyelitis in the diabetic foot

BACKGROUND Osteomyelitis in the diabetic foot is a difficult problem with multiple etiologies. The effects of peripheral vascular disease, neuropathy, and repetitive trauma all interact to produce complex lesions with exposed bone, surrounding cellulitis, and gangrenous changes. METHODS We performed a retrospective study over a 14-year period at a community hospital looking at osteomyelitis in the diabetic foot. We looked at the contributing factors, organisms involved, most common locations, physical findings, and surgical procedures necessary to treat this condition. The purpose of the study was to determine the incidence and effect of peripheral vascular disease in diabetic patients with foot ulcers. RESULTS There were a total of 150 patients requiring 278 hospitalizations over the 14-year period who represented 14% of all diabetic admissions. A total of 438 surgical procedures were necessary in these patients, with the most common being debridement (39%) and toe amputation (19%). There were 6 deaths (4%) in this series, and leg amputation was necessary in 21 patients (14%). A vascular bypass was necessary for healing and limb salvage in 36 patients (24%). Most of the bypasses (85%) were with autogenous tissue to the distal leg in order to limit the extent of amputation and to preserve a functional limb. CONCLUSION Ischemia is often a contributing factor in the diabetic foot ulcer that must be recognized and treated to avoid prolonged hospitalization, spreading infection, and unnecessary amputation.

Stimulation of microsomal dimethylnitrosamine-N-demethylase by pretreatment of mice with acetone

To further investigate the relationship between in vivo microsomal enzyme modifiers and in vitro dimethylnitrosamine (DMN) metabolism, male C57BL/6J mice were pretreated with acetone or Aroclor 1254, two compounds known to influence DMN-N-demethylase activity. Pretreatment with acetone enhanced the in vitro microsomal activity of DMN-N-demethylase, as measured by formaldehyde production from DMN. Accompanying this acetone-enhanced demethylase activity was an increase in the covalent binding of [14C]DMN to RNA, protein and DNA. Four distinct Km values dependent on the substrate concentration were observed for the N-demethylase present in control microsomes. Only one Km value was observed for the demethylase in microsomes from acetone-treated animals, but it was significantly lower than the lowest Km observed in the control microsomes. At DMN concentrations of 1 and 10 mM, acetone significantly increased N-demethylation of DMN as compared to control, but not at 100 mM DMN. Aroclor 1254 pretreatment repressed DMN-N-demethylase at 1 mM DMN but enhanced it at 100 mM. These results suggest that there may be multiple forms of DMN-N-demethylase which are dependent on DMN concentration and respond differently to modifiers of the microsomal drug-metabolizing enzymes.

The origin of lower extremity deep vein thrombi in acute venous thrombosis

BACKGROUND: It has been taught that most deep venous thromboses (DVT) begin in the deep veins of the calf and propagate proximally. The duplex ultrasound scan, with its noninvasive characteristics and accuracy, has brought this premise into question. The purpose of this study was to determine the pattern and distribution of acute DVT as well as the different types of thrombi. METHODS: We performed a retrospective review of all duplex scans ordered for a diagnosis of acute lower extremite DVT at a 200-bed hospital over a 5-year period. RESULTS: There were 3,585 examinations performed on 2,654 patients. There were 461 patients (17.4%) with a venous thrombosis. Four types of venous thrombosis were identified: an isolated thrombosis in one venous segment (34%), a thrombosis extending over two or more contiguous segments (52%), multiple thromboses in noncontiguous segments (8%), and bilateral thrombi in different locations (6%). CONCLUSION: Calf vein thrombi represented 24% of all DVT. Thrombi in the major veins of the thigh and popliteal space without calf involvement were present in 49% of all DVT. The data in this paper indicate that most significant deep venous thromboses do not begin in the calf but instead arise in the proximal thigh or groin.

Isoflavones Improve Plasma Homocysteine Status and Antioxidant Defense System in Healthy Young Men at Rest but Do Not Ameliorate Oxidative Stress Induced by 80% VO2pk Exercise

Aims: (1) Determination of whether isoflavones, as antioxidants and estrogen-like substances, reduce the atherosclerotic process. (2) Assessment of isoflavone anti-atherosclerotic effectiveness by means of measuring plasma markers of atherosclerosis: homocysteine (Hcy), antioxidant status, and lipid peroxidation. (3) Testing of isoflavone antioxidant effectiveness in the presence and absence of oxidative stress induced by exercise. Methods: Thirty subjects paired by aerobic fitness level were randomly assigned to either a placebo or high-genistein isoflavone extract (HGI, 150 mg/day) treatment. Blood samples were collected before and within 5 min, after 30 min at 80% peak oxygen consumption (VO2pk) exercise, and before and after 4-week supplementation. Results: Plasma genistein and daidzein were significantly increased by 4-week HGI supplementation before and after exercise (p < 0.05). HGI decreased pre-exercise (pre-ex) plasma malondialdehyde (MDA) (p < 0.05) and Hcy (p = 0.01), and increased pre-ex blood total glutathione (TGSH) (p = 0.01), but did not diminish the increase of MDA and the decrease of TGSH due to the exercise. Furthermore, HGI supplementation enhanced pre-ex total antioxidant capacity (p < 0.05), but did not influence plasma vitamin C and E and uric acid concentrations. Conclusion: Isoflavones reduce plasma Hcy and have antioxidant activity in healthy young men. However, the effect of isoflavones on antioxidant systems may not be potent enough to diminish an abrupt surge of oxidative stress due to acute exercise.

Role of moth ocelli in timing flight initiation at dusk

ABSTRACT. The role of ocelli in timing flight initiation of cabbage looper moths, Trichoplusia ni (Hübner) (Noctuidae), at dusk was studied under simulated sunset conditions using a multichannel actograph. The mean time of flight initiation was determined for control, sham (sham/occluded, sham ablated, unilateral ablated) and experimental (ocellus occluded, ocellus ablated moths). Ocellus occlusion delayed flight initiation on the first day following treatment but was less effective on the subsequent days. Ocellus ablation also delayed flight initiation on the first day, and also produced pronounced delays on subsequent days. In studies where the sunset was advanced 1 h, control sham ocellus occluded and unilaterally ocellus ablated moths responded to the advance, but bilaterally ocellus ablated moths did not. These results indicate that moths make use of input from the ocelli in determining the threshold light intensity for flight and in making adjustments to small light‐phase changes.

The poisson and chi-squared approximations as compared with the true upper-tail probability of Pearson's X2 for equiprobable multinomials

Abstract The exact tail probability P of Pearsons X2, for equiprobable t-category multinomial samples of size N, was computed to within ±0.00002 for over 250 combinations of N and t, mostly in the region 10≤N≤80, 2≤t≤160. The results are used to assess the quality of the Poisson approximation, and of three chi-squared approximations: the usual uncorrected one, the one with the continuity correction of Cochran (1942), and the one with the adjustment of Nass (1959, pp. 368–369). A concise table of chi-squared ‘correction factors’ is presented also. Given a realization of X2, a pair of correction factors can be used in conjunction with the standard tabular chi-squared approximation to produce accurate lower and upper bounds to the exact tail probability.

Detecting changes in trends in water quality using modified Kendall's tau

A method for testing the equivalence of two modified Kendalls tau nonparametric correlation coefficients, neither necessarily equal to zero, is presented. Several estimators of the variance taumod were evaluated using simulation. A bootstrap estimate, the standard null-case variance estimate, and a delta method variance estimate are shown to provide reasonable estimates in different circumstances. The results of a power study are also given, including a comparison with the test of equivalence of two Pearson correlation coefficients. The variance estimators and their corresponding Wald-type tests were studied under different conditions, including the presence of varying degrees of serial correlation, different distributions, and different percentages of tied data. The power study revealed that in the presence of serial correlation, a new method for estimating variance, called the effective sample size bootstrap, allowed the hypothesis test to consistently hold its level while no other method of estimating the variance did. Finally, through the use of an example, it is demonstrated how this test can be used to detect changes in trend of water-quality variables over time. Copyright

Differential Response of a Virginia Common Lambsquarters (Chenopodium album) Collection to Glyphosate

Abstract Control of common lambsquarters with POST applications of glyphosate in glyphosate-resistant crops generally has been effective. In 2002, common lambsquarters plants from Westmoreland County, VA, were identified after not being controlled with a POST glyphosate application in glyphosate-resistant soybean. Plants from this site that survived glyphosate were collected in both 2002 and 2004. The objective of this research was to evaluate the susceptibility of F1 and F2 progeny from these common lambsquarters plants, relative to the susceptibility of common lambsquarters collected in Montgomery County, VA. F1 progeny of the Westmoreland plants from both the 2002 and 2004 collections showed reduced response to glyphosate relative to the Montgomery collection. Vigor reduction of F1 progeny from three 2004 Westmoreland source plants with 0.84 kg ae ha−1 of glyphosate ranged from 66 to 85% at 28 d after treatment (DAT), compared with 89% for the Montgomery collection. Evaluation of four Westmoreland F2 common lambsquarters lines derived from 2002 collections indicated significant differences in glyphosate sensitivity. Fifteen F2 lines were generated from 2004 collections from each of three Westmoreland source plants and from the Montgomery source. For the least sensitive Westmoreland source, vigor reduction ranged from only 24 to 36% across F2 lines in response to 1.68 kg ha−1 of glyphosate at 28 DAT relative to 55 to 100% for the Montgomery source. I50 estimates for fresh weight reduction were 0.91 and 0.32 kg ha−1, for these sources, respectively. Sequential treatments of 0.42, 1.26, and 1.68 kg ha−1 applied at 3-wk intervals to the least susceptible 2004 Westmoreland F2 line resulted in only 37% vigor reduction and no mortality among 360 treated plants. Nomenclature: Glyphosate; common lambsquarters, Chenopodium album L. CHEAL; soybean, Glycine max L. Merr

Monitoring pesticide and nitrate in Virginia's groundwater:a pilot study

Between October 1992 and February 1993, a total of 359 private wells in Northampton County were sampled and data on water-quality variables (temperature, pH, and conductivity), well construction, and site characteristics were collected. The groundwater samples were analyzed for aldicarb, alachlor, atrazine, carbofuran, linuron, methomyl, metolachlor, metribuzin, napropamide, pendimethalin, pronamide, simazine, and nitrate. The wells were stratified into shallow wells, withdrawing water from the unconfined aquifer, and deep wells, withdrawing water from the deeper confined aquifers. The study was undertaken as a pilot study to demonstrate the applicability of a recently developed framework for evaluating the extent of pesticide contamination in Virginia’s groundwater. Pesticides were detected in 14% of the shallow wells and in 7% of the deep wells sampled. Pesticide detection was associated with the well depth, with a higher probability of detecting a pesticide in the shallow unconfined aquifer than in the deeper aquifers. Nitrate above the U.S. EPA drinking water standard of 10 mg/L was found in 17% of the shallow and 1% of the deep wells. Pesticide and nitrate detections were not significantly related to well and site characteristics, such as crop type, location of well head, and distance to the nearest water body.