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Cantor GH, Caswell JL, Crissman JW, Gillette DM, Gunson DE, Hogenesch H, Kiupel M, Mense MG, Miller MA, Rush LJ, Leger JAS, Schoeb TR, Sellers RS, Sills RC, Swayne DE, Thomas HC, Ward JM, Alden CL. Veterinary pathology and peer review. Vet Pathol 2009; 46:173-5. [PMID: 19261628 DOI: 10.1354/vp.46-2-173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Bangari DS, Miller MA, Stevenson GW, Thacker HL, Sharma A, Mittal SK. Cutaneous and systemic poxviral disease in red (Tamiasciurus hudsonicus) and gray (Sciurus carolinensis) squirrels. Vet Pathol 2009; 46:667-72. [PMID: 19276066 DOI: 10.1354/vp.08-vp-0305-b-bc] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
From September 2005 through October 2006, fibromatosis was diagnosed in 2 red squirrels (Tamiasciurus hudsonicus) and 1 gray squirrel (Sciurus carolinensis). All 3 squirrels had multifocal to coalescing, tan, firm alopecic cutaneous nodules. Two squirrels also had pulmonary nodules. Histologically, the cutaneous nodules had marked epidermal hyperplasia, with ballooning degeneration of keratinocytes, spongiosis, and eosinophilic cytoplasmic inclusions. The dermis was expanded by proliferation of atypical mesenchymal cells with cytoplasmic inclusions. Additional findings included pulmonary adenomatous hyperplasia with cytoplasmic inclusions, renal tubular epithelial hyperplasia with cytoplasmic inclusions, atypical mesenchymal proliferation in the liver, and atypical mesenchymal proliferation with cytoplasmic inclusions in the seminal vesicles. Ultrastructurally, poxviral particles were observed in skin scrapings and sections of cutaneous and pulmonary nodules. Polymerase chain reaction targeting the highly conserved Leporipoxvirus DNA polymerase gene was positive using DNA extracted from the cutaneous lesions of all 3 squirrels. Nucleotide sequence of the 390 base PCR amplicons was closely related to that of other members of the genus Leporipoxvirus. To the authors' knowledge, this is the first report of cutaneous and systemic poxviral disease in American red squirrels with molecular characterization of the squirrel fibroma virus.
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Recker RR, Bare SP, Smith SY, Varela A, Miller MA, Morris SA, Fox J. Cancellous and cortical bone architecture and turnover at the iliac crest of postmenopausal osteoporotic women treated with parathyroid hormone 1-84. Bone 2009; 44:113-9. [PMID: 18983947 DOI: 10.1016/j.bone.2008.09.019] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Revised: 09/12/2008] [Accepted: 09/22/2008] [Indexed: 11/30/2022]
Abstract
Treatment with parathyroid hormone [PTH(1-84)] increases lumbar spine bone mineral density and decreases vertebral fractures, but its effects on bone microarchitecture are unknown. We obtained iliac crest biopsies from postmenopausal osteoporotic women given placebo (n=8) or 100 microg PTH(1-84) for 18 (n=8) or 24 (n=7) months to assess cancellous and cortical bone formation and structure. At 18 months, cancellous bone volume (BV/TV) measured by microcomputed tomography and histomorphometry was 45-48% higher in subjects treated with PTH(1-84) versus placebo, a result of higher trabecular number (Tb.N) and thickness. The higher Tb.N appeared to result from intratrabecular tunneling. Connectivity density was higher and structure model index was lower, indicating a better connected and more plate-like trabecular architecture. Cancellous bone formation rate (BFR) was 2-fold higher in PTH(1-84)-treated subjects, primarily because of greater mineralizing surface. Osteoblast and osteoid surfaces were a nonsignificant 58% and 35%, respectively, higher with PTH(1-84) treatment. Osteoclast and eroded surface were unaffected by PTH(1-84). There were no effects of PTH(1-84) treatment on cortical thickness, or endocortical or periosteal BFR, but cortical porosity tended to be higher. Although cancellous BFR was lower at 24 than at 18 months, measures of cancellous and cortical bone structure were similar at both timepoints. The bone produced by PTH(1-84) had normal lamellar structure and mineralization with no abnormal histology. In conclusion, when compared with placebo, treatment of osteoporotic women with PTH(1-84) was associated with higher BV/TV and trabecular connectivity, with a more plate-like architecture, all consistent with the lower vertebral fracture incidence.
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Kasting GB, Miller MA, Bhatt VD. A spreadsheet-based method for estimating the skin disposition of volatile compounds: application to N,N-diethyl-m-toluamide (DEET). JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2008; 5:633-644. [PMID: 18668403 DOI: 10.1080/15459620802304245] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The disposition of N,N-diethyl-3-methylbenzamide (DEET) applied to split-thickness human cadaver skin was measured in modified Franz cells maintained at 32 degrees C and fitted with a vapor trap. Ethanolic solutions of DEET (1% w/w) spiked with (14)C radiolabel were applied to skin at a dose of 10 microL per cell, corresponding to a DEET dose of 127 microg/cm(2). Room air was drawn over the skin at velocities ranging from 10-100 mL/min. Evaporation of radiolabel from the skin surface and absorption into the receptor solution were monitored for 24 hr post-dose. The percentage of radioactivity collected in the vapor trap after 24 hr increased with airflow, ranging from 16 +/- 4% at 10 mL/min to 59 +/- 7% at 70 mL/min. The percentage of radioactivity absorbed through the skin after 24 hours decreased with increasing airflow, ranging from 69 +/- 7% at 10 mL/min to 20 +/- 1% at 80 mL/min. Tissue retention after 24 hr was 6-14% of the radioactive dose with no clear correlation to airflow. This data as well as DEET absorption data from two previous in vitro studies in which dose and location (fume hood or bench top) was varied were analyzed in terms of a recently developed diffusion/evaporation model for skin implemented on an Excel spreadsheet. A priori model calculations based on independently estimated transport parameters (Model 1) were compared with calculations based on fitted parameters (Models 2 and 3). The analysis of the combined dataset (n = 272 observations) showed that the Model 1 estimates matched the cumulative disposition profiles to within a root mean square error of 12.4% of the applied dose (r(2) = 0.65), whereas the Model 2 and Model 3 fits matched to within 9.4% (r(2) = 0.80) and 6.5% (r(2) = 0.91), respectively. The Model 3 fits were obtained using a concentration-dependent diffusivity of DEET in the stratum corneum, the value of which increased 3.4-fold between low concentrations and saturation. This result was consistent with the mild skin penetration enhancement effect for DEET reported elsewhere. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a word document containing tables and figures including more information on the spreadsheet skin absorption model.]
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Bhatt VD, Soman RS, Miller MA, Kasting GB. Permeation of tecnazene through human skin in vitro as assessed by HS-SPME and GC-MS. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:6587-6592. [PMID: 18800534 DOI: 10.1021/es800107k] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Permeation of tecnazene into and through human cadaver skin in vitro was assessed using a CC-MS method employing HS-SPME for receptor solution analyses. Two doses of tecnazene dissolved in acetone, corresponding to 103 and 864 microg/cm2 of tecnazene, were applied to skin mounted on Franz diffusion cells and placed in a fume hood. Cells were either occluded with aluminum foil or left unoccluded. Total absorption of tecnazene (dermis + receptor fluid) after 48 h was 2.2-6.1% of the applied dose for the unoccluded treatments and 22-33% for the occluded treatments. Potentially absorbed dose including all tecnazene that may have eventually permeated the skin ranged from 10% unoccluded to 42-53% occluded. Accumulation in the receptor solutions was satisfactorily described by a working diffusion model after upward adjustment of the partition coefficient for tecnazene in all skin layers by a factor of 5-16 versus a priori values. However, residual amounts of tecnazene in both the epidermis and dermis were higher than those estimated from the model, suggesting the existence of tissue binding not accounted for in the calculation. The results indicate that the diffusion model as presently calibrated may significantly underestimate both systemic absorption and skin concentrations of highly lipophilic compounds, as predicted from data generated from in vitro skin permeation assays. Model predictions could be improved by better accounting for partitioning into the epidermis and dermis.
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Ramos-Vara JA, Wu CC, Mitsui I, Lin TL, Miller MA. Metritis, valvular endocarditis, and septicemia by Actinobacillus equuli in a gilt in the United States. Vet Pathol 2008; 45:495-9. [PMID: 18587096 DOI: 10.1354/vp.45-4-495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A 1-year-old pregnant Yorkshire gilt was found dead with no previous clinical signs. Gross findings included metritis, splenomegaly, and valvular endocarditis. Bacterial endocarditis (in the mitral and tricuspid valves) and metritis with dissemination to multiple organs was diagnosed by using histologic examination. Gram-negative coccobacillary organisms present in the valvular lesions were characterized as Actinobacillus equuli by using polymerase chain reaction examination on formalin-fixed, paraffin-embedded tissues (FFPE). A. equuli is rarely reported as a cause of septicemia in pigs in Europe. A. equuli in pigs in the United States has been reported only twice and not, to our knowledge, in the last 30 years. This is the first time that molecular techniques have been used to characterize this organism in FFPE porcine tissues.
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Collier RJ, Miller MA, McLaughlin CL, Johnson HD, Baile CA. Effects of recombinant bovine somatotropin (rbST) and season on plasma and milk insulin-like growth factors I (IGF-I) and II (IGF-II) in lactating dairy cows. Domest Anim Endocrinol 2008; 35:16-23. [PMID: 18325721 DOI: 10.1016/j.domaniend.2008.01.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Revised: 01/16/2008] [Accepted: 01/16/2008] [Indexed: 10/22/2022]
Abstract
During two studies, effects of recombinant bovine somatotropin (rbST) on plasma and milk IGF's in cows adapted to summer (S; 12 cows) or winter (W; 12 cows) conditions were evaluated. Each study consisted of on-farm periods (30 days) followed by climatology chamber periods (CC; 30 days). Cows were given daily injections of rbST, Sometribove, USAN (25mg/day; 6 cows each study) or saline (control; 6 cows each study). During on-farm periods, blood and milk (am and pm) samples were collected once weekly. During CC periods, blood samples were collected every 2 days and milk samples (am and pm) were collected daily. Plasma IGF-I and IGF-II were increased in cows treated with rbST. A pronounced seasonal pattern in basal and rbST-stimulated plasma IGF-I but not IGF-II was detected. Higher basal and rbST-stimulated plasma IGF-I concentrations in S occurred despite large decreases in feed intake and energy balance. Milk IGF-I and IGF-II was not affected by rbST treatment or season. Although milk IGF-I and IGF-II concentrations were unaffected by rbST treatment, total IGF-output increased due to increased milk yield. The observed seasonal patterns in plasma IGF-I may be indicative of seasonal differences in the coupling of the somatotropin-IGF axis. In particular, we failed to detect an uncoupling of the somatotropin-IGF-I axis in S despite an induced negative energy balance during thermal stress.
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Webster JD, Miller MA, Vemulapalli R. Encephalitozoon cuniculi-associated placentitis and perinatal death in an alpaca (Lama pacos). Vet Pathol 2008; 45:255-8. [PMID: 18424843 DOI: 10.1354/vp.45-2-255] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Placentitis, premature birth, and perinatal death were associated with Encephalitozoon cuniculi infection in an alpaca. Histologically, chorionic trophoblasts contained many Gram-positive, period acid-Schiff positive, variably acid-fast spores. Multifocal necrosis and infiltration by lymphocytes, eosinophils, and neutrophils were scattered throughout the chorionic membrane. Spores in trophoblasts were approximately 1 microm x 2 microm, thick-walled, and contained polar filaments and polar vacuoles consistent with microsporidia. The presence of E. cuniculi DNA was confirmed by sequencing the polymerase chain reaction amplicon from frozen placental tissue. A few glial nodules were scattered throughout the cerebrum, and mild lymphocytic inflammation was present in the heart, liver, and lung. No organisms were detected in tissues other than the placenta. This is the first reported case of E. cuniculi infection in an alpaca.
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Miller MA, Bare SP, Recker RR, Smith SY, Fox J. Intratrabecular tunneling increases trabecular number throughout the skeleton of ovariectomized rhesus monkeys treated with parathyroid hormone 1-84. Bone 2008; 42:1175-83. [PMID: 18387869 DOI: 10.1016/j.bone.2008.01.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 01/24/2008] [Accepted: 01/27/2008] [Indexed: 11/19/2022]
Abstract
Daily treatment of ovariectomized (OVX) adult rhesus monkeys with human parathyroid hormone (PTH) 1-84 for 16 months increases trabecular bone volume (BV/TV), number (Tb.N) and connectivity at lumbar vertebra-3 (L3) and thoracic vertebra-10. We proposed that the increased Tb.N and connectivity was achieved by stimulation of intratrabecular tunneling. Using histomorphometry to determine frequency of events, we have now quantified intratrabecular tunneling at L3 and extended it to investigate the effects of PTH(1-84) treatment on trabecular bone at the proximal femur, distal radius and iliac crest of these animals. At L3, tunneling frequency was low in control sham and OVX animals ( approximately 0.05/mm(2)) but increased significantly in PTH(1-84)-treated animals (0.27, 0.49 and 0.95/mm(2) with the 5, 10 and 25 microg/kg doses, respectively). Very similar tunneling frequencies were observed at all skeletal sites in all groups. Iliac crest biopsies were also collected at baseline and after 6 months of treatment and showed significant time- and dose-related increases in tunnels. Although the pattern and magnitude of response varied slightly from site to site, PTH(1-84) treatment significantly increased Tb.N, as well as BV/TV and bone formation rate at all skeletal sites. A modest but statistically significant increase in trabecular thickness occurred only at the iliac crest. In summary, intratrabecular tunneling is rare in control monkeys, but increased substantially with PTH(1-84) treatment. This phenomenon provides a plausible explanation for the PTH(1-84)-induced increase in Tb.N observed in OVX monkeys. Moreover, these analyses allowed a comparison of the effects PTH(1-84) treatment on trabecular bone at multiple locations.
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Kempf JG, Marohn JA, Carson PJ, Shykind DA, Hwang JY, Miller MA, Weitekamp DP. An optical NMR spectrometer for Larmor-beat detection and high-resolution POWER NMR. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:063904. [PMID: 18601414 DOI: 10.1063/1.2936257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Optical nuclear magnetic resonance (ONMR) is a powerful probe of electronic properties in III-V semiconductors. Larmor-beat detection (LBD) is a sensitivity optimized, time-domain NMR version of optical detection based on the Hanle effect. Combining LBD ONMR with the line-narrowing method of POWER (perturbations observed with enhanced resolution) NMR further enables atomically detailed views of local electronic features in III-Vs. POWER NMR spectra display the distribution of resonance shifts or line splittings introduced by a perturbation, such as optical excitation or application of an electric field, that is synchronized with a NMR multiple-pulse time-suspension sequence. Meanwhile, ONMR provides the requisite sensitivity and spatial selectivity to isolate local signals within macroscopic samples. Optical NMR, LBD, and the POWER method each introduce unique demands on instrumentation. Here, we detail the design and implementation of our system, including cryogenic, optical, and radio-frequency components. The result is a flexible, low-cost system with important applications in semiconductor electronics and spin physics. We also demonstrate the performance of our systems with high-resolution ONMR spectra of an epitaxial AlGaAs/GaAs heterojunction. NMR linewidths down to 4.1 Hz full width at half maximum were obtained, a 10(3)-fold resolution enhancement relative any previous optically detected NMR experiment.
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Bourjeily G, Khalil H, Miller MA, O'Connor K, Rosene-Montella K. Pregnancy and delivery in a patient with hypoplastic lung and dyspnoea. J OBSTET GYNAECOL 2008; 28:228-9. [PMID: 18393028 DOI: 10.1080/01443610801916205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Crump JA, Ram PK, Gupta SK, Miller MA, Mintz ED. Part I. Analysis of data gaps pertaining to Salmonella enterica serotype Typhi infections in low and medium human development index countries, 1984-2005. Epidemiol Infect 2008; 136:436-48. [PMID: 17686194 PMCID: PMC2870843 DOI: 10.1017/s0950268807009338] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2007] [Indexed: 11/05/2022] Open
Abstract
There are only 10 contemporary, population-based studies of typhoid fever that evaluate disease incidence using blood culture for confirmation of cases. Reported incidence ranged from 13 to 976/100 000 persons per year. These studies are likely to have been done preferentially in high- incidence sites which makes generalization of data difficult. Only five of these studies reported mortality. Of these the median (range) mortality was 0% (0-1.8%). Since study conditions usually involved enhanced clinical management of patients and the studies were not designed to evaluate mortality as an outcome, their usefulness for generalizing case-fatality rates is uncertain. No contemporary population-based studies reported rates of complications. Hospital-based typhoid fever studies reported median (range) complication rates of 2.8% (0.6-4.9%) for intestinal perforation and case-fatality rates of 2.0% (0-14.8%). Rates of complications other than intestinal perforation were not reported in contemporary hospital-based studies. Hospital-based studies capture information on the most severe illnesses among persons who have access to health-care services limiting their generalizability. Only two studies have informed the current understanding of typhoid fever age distribution curves. Extrapolation from population-based studies suggests that most typhoid fever occurs among young children in Asia. To reduce gaps in the current understanding of typhoid fever incidence, complications, and case-fatality rate, large population-based studies using blood culture confirmation of cases are needed in representative sites, especially in low and medium human development index countries outside Asia.
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Abstract
The diffusivity of water in human nail at 32 degrees C was determined for cadaveric, human finger nails having water contents ranging from 0.536 g H(2)O/g dry nail to 0.035 g H(2)O/g dry nail by measuring the desorption of tritiated water from nails suspended in water or in the vapor phase above salt solutions yielding a range of relative humidities (RH). Diffusivity increased with increasing RH from (7.7 +/- 1.3) x 10(-10) cm(2) s(-1) at 15% RH to (3.2 +/- 1.1) x 10(-7) cm(2) s(-1) in the liquid phase study at 100% RH, a more than 400-fold increase. The diffusivity values, which may be understood in terms of the equilibrium water content of the nail and a free volume theory for diffusion in hydrophilic polymers, were consistent with water diffusivities measured in other keratinized tissues including wool, horn and the corneocyte phase of stratum corneum. Analysis of the tritium desorption data was complicated by a tritium exchange process between (3)H(2)O and nail keratin, the kinetics of which are presented in part. The combination of the concentration-dependent water diffusivity with the natural water activity gradient in nail in vivo leads to the prediction of a nonlinear steady-state water concentration profile in human nail in vivo which, in turn, has implications for ungual drug delivery.
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Jensen KC, Turbin DA, Leung S, Miller MA, Johnson K, Norris B, Hastie T, McKinney S, Nielsen TO, Huntsman DG, Gilks CB, West RB. New cutpoints to identify increased HER2 copy number: analysis of a large, population-based cohort with long-term follow-up. Breast Cancer Res Treat 2008; 112:453-9. [PMID: 18193353 DOI: 10.1007/s10549-007-9887-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2007] [Accepted: 12/27/2007] [Indexed: 01/08/2023]
Abstract
BACKGROUND HER2 gene amplification and/or protein overexpression in breast cancer is associated with a poor prognosis and predicts response to anti-HER2 therapy. We examine the natural history of breast cancers in relationship to increased HER2 copy numbers in a large population-based study. PATIENTS AND METHODS HER2 status was measured by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) in approximately 1,400 breast cancer cases with greater than 15 years of follow-up. Protein expression was evaluated with two different commercially-available antibodies. RESULTS We looked for subgroups of breast cancer with different clinical outcomes, based on HER2 FISH amplification ratio. The current HER2 ratio cut point for classifying HER2 positive and negative cases is 2.2. However, we found an increased risk of disease-specific death associated with FISH ratios of >1.5. An 'intermediate' group of cases with HER2 ratios between 1.5 and 2.2 was found to have a significantly better outcome than the conventional 'amplified' group (HER2 ratio >2.2) but a significantly worse outcome than groups with FISH ratios less than 1.5. CONCLUSION Breast cancers with increased HER2 copy numbers (low level HER2 amplification), below the currently accepted positive threshold ratio of 2.2, showed a distinct, intermediate outcome when compared to HER2 unamplified tumors and tumors with HER2 ratios greater than 2.2. These findings suggest that a new cut point to determine HER2 positivity, at a ratio of 1.5 (well below the current recommended cut point of 2.2), should be evaluated.
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Kretsos K, Miller MA, Zamora-Estrada G, Kasting GB. Partitioning, diffusivity and clearance of skin permeants in mammalian dermis. Int J Pharm 2008; 346:64-79. [PMID: 17703903 DOI: 10.1016/j.ijpharm.2007.06.020] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Revised: 06/01/2007] [Accepted: 06/05/2007] [Indexed: 11/28/2022]
Abstract
The partition coefficients (K(de)) and diffusivities (D(de)) of compounds in mammalian dermis were examined through an analysis of in vitro permeation data obtained from the literature combined with experimental results with the test permeant, (3)H-testosterone. The literature data involved 26 compounds ranging in molecular weight from 18 to 476 Da and four species-human, guinea pig, rat and mouse. Testosterone was studied by permeation and desorption measurements employing excised human dermis in the presence and absence of external serum albumin. Mathematical models for both K(de) and D(de) were developed. The K(de) model involved ionization, binding to extravascular serum proteins and partitioning into a small lipid compartment. The D(de) model employed a free diffusivity with a liquid-like size dependence multiplied by a binding factor derived from K(de). An additional analysis considered in vivo dermal concentration profiles of topically applied permeants. Literature data for 5 of 6 permeants were shown to be well described by a previously published model for capillary clearance in the dermis, which leads to an exponential decay of concentration with depth. Computed decay lengths (1/e values) ranged from 210 to 920 microm, and the corresponding clearance rate constants k(de) ranged from 0.9 x 10(-4) to 14 x 10(-4)s(-1) (n=8). Departures from the exponential decay profile are discussed in terms of non-uniform capillary clearance and incomplete attainment of a steady-state.
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Miller MA, Sorokin YM, Stepanov NS. Covariance of Maxwell equations and comparison of electrodynamic systems. ACTA ACUST UNITED AC 2007. [DOI: 10.1070/pu1977v020n03abeh005347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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118
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Fox J, Miller MA, Newman MK, Recker RR, Turner CH, Smith SY. Effects of daily treatment with parathyroid hormone 1-84 for 16 months on density, architecture and biomechanical properties of cortical bone in adult ovariectomized rhesus monkeys. Bone 2007; 41:321-30. [PMID: 17573250 DOI: 10.1016/j.bone.2007.04.197] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Revised: 04/20/2007] [Accepted: 04/23/2007] [Indexed: 11/30/2022]
Abstract
Treatment with parathyroid hormone 1-84 (PTH) or teriparatide increases osteonal remodeling and decreases bone mineral density (BMD) at cortical (Ct) bone sites but may also increase bone size. Decreases in BMD and increases in size exert opposing effects on bone strength. In adult ovariectomized (OVX) rhesus monkeys, we assessed the effects of daily PTH treatment (5, 10 or 25 microg/kg) for 16 months on BMD at the radial, tibial and femoral diaphyses, and on biomechanical properties (3-point bending) of radial cortical bone and the femoral diaphysis. PTH treatment did not affect areal BMD measured by dual-energy X-ray absorptiometry at the tibial diaphysis but caused a rapid, dose-related decrease at the distal radial diaphysis. Peripheral quantitative computed tomography at the radial and femoral diaphyses confirmed a significant PTH dose-related decrease in volumetric Ct.BMD caused primarily by increased cortical area. Significant increases in cortical thickness were the result of nonsignificant increases in periosteal length and decreases in endocortical length. Histomorphometry revealed increased endocortical bone formation at the tibial diaphysis and rib, higher Haversian remodeling at the rib and increased cortical porosity at the rib and tibia. Biomechanical testing at the femoral diaphysis showed that PTH treatment had no effect on peak load, but significantly decreased stiffness and increased work-to-failure (the energy required to break the bone). Similar changes occurred in radial cortical beams but only stiffness was changed significantly. Thus, PTH treatment of OVX rhesus monkeys decreased BMD and stiffness of cortical bone but did not affect peak load, likely because of increased bone size. However, PTH treatment increased the energy required to break the femur making it more resistant to fracture.
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Gupta SK, Keck J, Ram PK, Crump JA, Miller MA, Mintz ED. Part III. Analysis of data gaps pertaining to enterotoxigenic Escherichia coli infections in low and medium human development index countries, 1984-2005. Epidemiol Infect 2007; 136:721-38. [PMID: 17686197 PMCID: PMC2870873 DOI: 10.1017/s095026880700934x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a common cause of profuse watery diarrhoea in the developing world, often leading to severe dehydration or death. We found only 15 population-based studies in low and medium human development index (HDI) countries from 1984 to 2005 that evaluate disease incidence. Reported incidence ranged from 39 to 4460 infections/1000 persons per year. The peak incidence of ETEC appeared to occur between ages 6 and 18 months. A median of 14% (range 2-36%) of diarrhoeal specimens were positive for ETEC in 19 facility- and population-based studies conducted in all age groups and 13% (range 3-39%) in 51 studies conducted in children only. Heat-labile toxin (LT)-ETEC is thought to be less likely to cause disease than heat-stable toxin (ST)-ETEC or LT/ST-ETEC. Because population-based studies involve enhanced clinical management of patients and facility-based studies include only the most severe illnesses, reliable data on complications and mortality from ETEC infections was unavailable. To reduce gaps in the current understanding of ETEC incidence, complications and mortality, large population-based studies combined with facility-based studies covering a majority of the corresponding population are needed, especially in low-HDI countries. Moreover, a standard molecular definition of ETEC infection is needed to be able to compare results across study sites.
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Ram PK, Crump JA, Gupta SK, Miller MA, Mintz ED. Part II. Analysis of data gaps pertaining to Shigella infections in low and medium human development index countries, 1984-2005. Epidemiol Infect 2007; 136:577-603. [PMID: 17686195 PMCID: PMC2870860 DOI: 10.1017/s0950268807009351] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
The global incidence of Shigella infection has been estimated at 80-165 million episodes annually, with 99% of episodes occurring in the developing world. To identify contemporary gaps in the understanding of the global epidemiology of shigellosis, we conducted a review of the English-language scientific literature from 1984 to 2005, restricting the search to low and medium human development countries. Our review yielded 11 population-based studies of Shigella burden from seven countries. No population-based studies have been conducted in sub-Saharan Africa or in low human development countries. In studies done in all age groups, Shigella incidence varied from 0.6 to 107 episodes/1000 person-years. S. flexneri was the most commonly detected subgroup in the majority of studies. Case-fatality rates ranged from 0% to 2.6% in population-based studies and from 0% to 21% in facility-based studies. This review highlights the large gaps in data on the burden of Shigella infections for low human development index countries and, more specifically, for sub-Saharan Africa.
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Messick KJ, Miller MA, Damron LA, Race A, Clarke MT, Mann KA. Vacuum-mixing cement does not decrease overall porosity in cemented femoral stems. ACTA ACUST UNITED AC 2007; 89:1115-21. [PMID: 17785755 PMCID: PMC2292250 DOI: 10.1302/0301-620x.89b8.19129] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The role of vacuum mixing on the reduction of porosity and on the clinical performance of cemented total hip replacements remains uncertain. We have used paired femoral constructs prepared with either hand-mixed or vacuum-mixed cement in a cadaver model which simulated intra-operative conditions during cementing of the femoral component. After the cement had cured, the distribution of its porosity was determined, as was the strength of the cement-stem and cement-bone interfaces. The overall fraction of the pore area was similar for both hand-mixed and vacuum-mixed cement (hand 6%; vacuum 5.7%; paired t-test, p = 0.187). The linear pore fractions at the interfaces were also similar for the two techniques. The pore number-density was much higher for the hand-mixed cement (paired t-test, p = 0.0013). The strength of the cement-stem interface was greater with the hand-mixed cement (paired t-test, p = 0.0005), while the strength of the cement-bone interface was not affected by the conditions of mixing (paired t-test, p = 0.275). The reduction in porosity with vacuum mixing did not affect the porosity of the mantle, but the distribution of the porosity can be affected by the technique of mixing used.
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Messick KJ, Miller MA, Damron LA, Race A, Clarke MT, Mann KA. Vacuum-mixing cement does not decrease overall porosity in cemented femoral stems: an in vitro laboratory investigation. THE JOURNAL OF BONE AND JOINT SURGERY. BRITISH VOLUME 2007; 89:1115-1121. [PMID: 17785755 PMCID: PMC2292250 DOI: 10.1302/0301-620x.89b8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The role of vacuum mixing on the reduction of porosity and on the clinical performance of cemented total hip replacements remains uncertain. We have used paired femoral constructs prepared with either hand-mixed or vacuum-mixed cement in a cadaver model which simulated intra-operative conditions during cementing of the femoral component. After the cement had cured, the distribution of its porosity was determined, as was the strength of the cement-stem and cement-bone interfaces. The overall fraction of the pore area was similar for both hand-mixed and vacuum-mixed cement (hand 6%; vacuum 5.7%; paired t-test, p = 0.187). The linear pore fractions at the interfaces were also similar for the two techniques. The pore number-density was much higher for the hand-mixed cement (paired t-test, p = 0.0013). The strength of the cement-stem interface was greater with the hand-mixed cement (paired t-test, p = 0.0005), while the strength of the cement-bone interface was not affected by the conditions of mixing (paired t-test, p = 0.275). The reduction in porosity with vacuum mixing did not affect the porosity of the mantle, but the distribution of the porosity can be affected by the technique of mixing used.
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Chowell G, Miller MA, Viboud C. Seasonal influenza in the United States, France, and Australia: transmission and prospects for control. Epidemiol Infect 2007; 136:852-64. [PMID: 17634159 PMCID: PMC2680121 DOI: 10.1017/s0950268807009144] [Citation(s) in RCA: 206] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Recurrent epidemics of influenza are observed seasonally around the world with considerable health and economic consequences. A key quantity for the control of infectious diseases is the reproduction number, which measures the transmissibility of a pathogen and determines the magnitude of public health interventions necessary to control epidemics. Here we applied a simple epidemic model to weekly indicators of influenza mortality to estimate the reproduction numbers of seasonal influenza epidemics spanning three decades in the United States, France, and Australia. We found similar distributions of reproduction number estimates in the three countries, with mean value 1.3 and important year-to-year variability (range 0.9-2.1). Estimates derived from two different mortality indicators (pneumonia and influenza excess deaths and influenza-specific deaths) were in close agreement for the United States (correlation=0.61, P60%) in healthy individuals who respond well to vaccine, in addition to periodic re-vaccination due to evolving viral antigens and waning population immunity.
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Fox J, Miller MA, Recker RR, Turner CH, Smith SY. Effects of treatment of ovariectomized adult rhesus monkeys with parathyroid hormone 1-84 for 16 months on trabecular and cortical bone structure and biomechanical properties of the proximal femur. Calcif Tissue Int 2007; 81:53-63. [PMID: 17551766 DOI: 10.1007/s00223-007-9036-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Revised: 04/10/2007] [Accepted: 04/10/2007] [Indexed: 10/23/2022]
Abstract
Treatment of monkeys and humans with parathyroid hormone (PTH) 1-84 stimulates skeletal remodeling, which increases trabecular (Tb) bone mineral density (BMD) but decreases cortical (Ct) BMD at locations where these bone types predominate. We report the effects of daily PTH treatment (5, 10, or 25 microg/kg) of ovariectomized (OVX) rhesus monkeys for 16 months on bone structure and biomechanical properties at the proximal femur, a mixed trabecular and cortical bone site. PTH reversed the OVX-induced decrease in BMD measured by dual-energy X-ray absorptiometry at the proximal femur, femoral neck, and distal femur. Peripheral quantitative computed tomography confirmed a significant decrease in Ct.BMD and an increase in Tb.BMD at the total proximal femur and at the proximal and distal femoral metaphyses. The decrease in Ct.BMD resulted primarily from increased area because cortical bone mineral content was unaffected by PTH. Histomorphometry revealed that PTH significantly increased the trabecular bone formation rate (BFR) as well as trabecular bone volume and number. PTH did not affect periosteal or haversian BFR at the femoral neck, but cortical porosity was increased slightly. PTH had no effects on stiffness or peak load measured using a shear test, whereas work-to-failure, the energy required to fracture, was increased significantly. Thus, PTH treatment induced changes in trabecular and cortical bone at the proximal femur that were similar to those occurring at sites where these bone types predominate. Together, the changes had no effect on stiffness or peak load but increased the energy required to break the proximal femur, thereby making it more resistant to fracture.
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Miller MA, Hartnett SE, Ramos-Vara JA. Interstitial cell tumor and Sertoli cell tumor in the testis of a cat. Vet Pathol 2007; 44:394-7. [PMID: 17491086 DOI: 10.1354/vp.44-3-394] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Testicular tumors are rarely reported in cats. We describe a case of interstitial cell tumor and Sertoli cell tumor in a cat that developed aggressive behavior and inappropriate urination 7 years after it was obtained from a shelter as an allegedly castrated 2 year old. At physical examination, the urine odor and the presence of penile papillae implied testosterone production. Testes were not palpable, but the left testis was found in the scrotum by surgical exploration and was mostly replaced by the 2 tumors. The interstitial cell tumor, but not the Sertoli cell tumor, was immunohistochemically positive for Melan-A, consistent with steroid production. Behavior improved after excision of the testis and penile papillae began to regress, but the cat was euthanatized 3 1/2 months after castration at the owner's request. Neither tumor had metastasized. The right testis was never found and was presumed to have been removed during the reported castration procedure.
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