bluuebunny/crossref_metadata_2025 huggingface dataset:
Bile acids enhance the activity of the insulin receptor and glycogen synthase in primary rodent hepatocytes
Authors: Han Song Iy , Studer Elaine , Gupta Seema , Fang Youwen , Qiao Liang , Li Weiqun , Grant Steven , Hylemon Philip B. , Dent Paul
Published: February 2004

Previously, we demonstrated that deoxycholic acid (DCA)-induced ERK1/2 and AKT signaling in primary hepatocytes is a protective response. In the present study, we examined the regulation of the phosphatidylinositol 3 (PI3) kinase/AKT/glycogen synthase (kinase) 3 (GSK3)/glycogen synthase (GS) pathway by bile acids. In primary hepatocytes, DCA activated ERBB1 (the epidermal growth factor receptor), ERBB2, and the insulin receptor, but not the insulin-like growth factor 1 (IGF-1) receptor. DCA-induced activation of the insulin receptor correlated with enhanced phosphorylation of insulin receptor substrate 1, effects that were both blocked by the insulin receptor inhibitor AG1024 and by expression of the dominant negative IGF-1 receptor (K1003R), which inhibited in trans. Expression of the dominant negative IGF-1 receptor (K1003R) also abolished DCA-induced AKT activation. Bile acid-induced activation of AKT and phosphorylation of GSK3 were blunted by the ERBB1 inhibitor AG1478 and abolished by AG1024. Bile acids caused activation of GS to a similar level induced by insulin (50 nM); both were blocked by inhibition of insulin receptor function and the PI3 kinase/AKT/GSK3 pathway. In conclusion, these findings suggest that bile acids and insulin may cooperate to regulate glucose storage in hepatocytes. (Hepatology 2004;39:456-463.)
Chronic liver disease mortality in the United States, 1990-1998
Authors: Vong Sirenda , Bell Beth P.
Published: February 2004

In 1998, chronic liver disease (CLD) was the tenth leading cause of death in the U.S. Alcohol and hepatitis C are thought to be important etiologies. However, traditional methods for calculating CLD mortality rates from death certificates may underestimate hepatitis C-related CLD mortality. We studied patterns of CLD deaths reported from 1990 through 1998, using an expanded definition that included death certificates where CLD, viral hepatitis, or CLD-related sequelae were reported as the underlying cause. We calculated overall age-specific and age-adjusted mortality rates, and according to demographic characteristics and recorded causes, and evaluated trends using linear regression modeling. CLD mortality declined 5% overall from 1990 through 1994 (12.1 to 11.6/100,000; P = 0.002), but remained unchanged from 1995 through 1998 (P = 0.366). Decreases were similar for all causes except hepatitis C, for which rates increased 220% from 1993 to 1998 (0.57 to 1.67/100,000). Rates declined in all racial-ethnic groups except American Indians and Alaska Natives (AI/AN), among whom rates were unchanged. Of 30,933 CLD deaths in 1998, 39% were coded as alcohol related, 15% as hepatitis C, 4% as hepatitis B, and 44% had no recorded cause. Age-adjusted rates were higher among males (47.6/100,000) than females (32.2/100,000) and among Hispanics (19.1/100,000) compared with non-Hispanics (10.8/100,000). Rates among AI/AN (28.7/100,000) were more than twice those of African Americans and whites (12.9/100,000 and 11.5/100,000, respectively). In conclusion, 1998 CLD deaths and the proportion attributable to viral hepatitis increased by 23% and 19%, respectively, compared with traditional methods. Mortality declines of the early 1990s were not sustained after 1994. Large disparities in CLD mortality remain, particularly among American Indians and Alaska Natives. (Hepatology 2004;39:476-483.)
Targeting portal pressure measurements: A critical reappraisal
Authors: Thalheimer Ulrich , Mela Maria , Patch David , Burroughs Andrew K.
Published: February 2004

Many of the complications of cirrhosis reflect the presence of portal hypertension, which is commonly expressed as the hepatic venous pressure gradient (HVPG). Baseline and repeat measurements of HVPG have been recommended for the management of patients with cirrhosis in the setting of pharmacologic prophylaxis of variceal bleeding and for gaining information about prognosis. However, published studies have demonstrated problems with the interpretation of the data on HVPG monitoring, making its use controversial. We view the current data as insufficient evidence to support the monitoring of a targeted reduction of HVPG as routine clinical practice. We recommend the performance of new prospective studies to establish the clinical importance of HVPG measurements. (Hepatology 2004;39:386-290.)
Depletion of mitochondrial DNA in liver under antiretroviral therapy with didanosine, stavudine, or zalcitabine
Authors: Walker Ulrich A. , Bäuerle Jochen , Laguno Montse , Murillas Javier , Mauss Stefan , Schmutz Günther , Setzer Bernhard , Miquel Rosa , Gatell José M. , Mallolas Josep
Published: February 2004

The “D drug” HIV reverse-transcriptase inhibitors zalcitabine, didanosine, and stavudine are relatively strong inhibitors of polymerase-gamma compared with the “non-D drugs” zidovudine, lamivudine, and abacavir. D drugs deplete mitochondrial DNA (mtDNA) in cultured hepatocytes. This mtDNA depletion is associated with an increased in vitro production of lactate. To investigate the origin of hyperlactatemia in HIV-infected patients and the effects of antiretroviral therapy on liver mtDNA, we biopsied liver tissue from 94 individuals with chronic hepatitis C virus (HCV) infection. Eighty subjects were coinfected with HIV. Serum lactate was measured at the time of biopsy. Hepatic mtDNA and liver histology were centrally assessed. Liver mtDNA content of HIV-infected patients receiving D drugs at the time of biopsy (n = 34) was decreased by 47% (P<.0001) compared with those without D drugs (n = 35). Aside from a possible association between HCV genotype I status and mtDNA depletion in multivariate analysis, there were no other virologic, immunologic, histologic, demographic or treatment-related variables that could explain the mtDNA depletion. Lactate was above the upper limit of normal in only three patients, all of whom were treated with D drugs. The mtDNA in each of them was lower than in any non-D drug patient and significantly (P = .017) depleted compared with D drug patients with normal lactate. In conclusion, D drug treatment is associated with decreased hepatic mtDNA in HIV-infected patients with chronic HCV infection. Moderate mtDNA depletion in liver does not necessarily lead to hyperlactatemia, but more pronounced decreases in hepatic mtDNA may be an important contributor to lactate elevation. (Hepatology 2004;39:311-317.)
SARS-associated viral hepatitis caused by a novel coronavirus: Report of three cases
Authors: Chau Tai-Nin , Lee Kam-Cheong , Yao Hung , Tsang Tak-Yin , Chow Tat-Chong , Yeung Yiu-Cheong , Choi Kin-Wing , Tso Yuk-Keung , Lau Terence , Lai Sik-To , Lai Ching-Lung
Published: February 2004

Liver impairment is commonly reported in up to 60% of patients who suffer from severe acute respiratory syndrome (SARS). Here we report the clinical course and liver pathology in three SARS patients with liver impairment. Three patients who fulfilled the World Health Organization case definition of probable SARS and developed marked elevation of alanine aminotransferase were included. Percutaneous liver biopsies were performed. Liver specimens were examined by light and electron microscopy, and immunohistochemistry. Reverse-transcriptase polymerase chain reaction (RT-PCR) using enhanced real-time PCR was applied to look for evidence of SARS-associated coronavirus infection. Marked accumulation of cells in mitosis was observed in two patients and apoptosis was observed in all three patients. Other common pathologic features included ballooning of hepatocytes and mild to moderate lobular lymphocytic infiltration. No eosinophilic infiltration, granuloma, cholestasis, fibrosis, or fibrin deposition was noted. Immunohistochemical studies revealed 0.5% to 11.4% of nuclei were positive for proliferative antigen Ki-67. RT-PCR showed evidence of SARS-associated coronavirus in the liver tissues, but not in the sera of all 3 patients. However, electron microscopy could not identify viral particles. No giant mitochondria, micro- or macro-vesicular steatosis was observed. In conclusion, hepatic impairment in patients with SARS is due to SARS-associated coronavirus infection of the liver. The prominence of mitotic activity of hepatocytes is unique and may be due to a hyperproliferative state with or without disruption of cell cycle by the coronavirus. With better knowledge of pathogenesis, specific therapy may be targeted to reduce viral replication and modify the disease course. (Hepatology 2004;39:302-310.)
A reciprocal and longitudinal investigation of the innovation process: the central role of shared vision in product and process innovation teams (PPITs)
Authors: Pearce Craig L. , Ensley Michael D.
Published: February 2004

This research longitudinally investigates the innovation process by examining the relationship between innovation effectiveness, shared vision, and product and process innovation team (PPIT) dynamics in the innovation process. The research was conducted with a sample of 71 PPITs. Results indicate that when teams are charged with implementation of sophisticated innovation, a complex set of team dynamics is set in motion. Our results indicate that innovation effectiveness and shared vision are reciprocally and longitudinally related and that shared vision and team dynamics are also reciprocally and longitudinally related. As such, this research suggests that shared vision occupies a core role in the team innovation process. Copyright © 2004 John Wiley & Sons, Ltd.
Molluscan successions from the Holocene tufa of St Germain‐le‐Vasson, Normandy (France) and their biogeographical significance
Authors: Limondin‐Lozouet Nicole , Preece Richard C.
Published: January 2004

A detailed molluscan succession from a 10 m thick deposit of Holocene tufa at St Germain‐le‐Vasson, Normandy, provides the most complete record from northern France and has shed new light on the historical biogeography of several species of land snail. The succession has been reconstructed from four profiles and a chronology provided by accelerator mass spectrometry radiocarbon dating of charcoal, wood and shell. The onset of tufa formation occurred after 9700±90 yr BP and persisted until 4213±77 yr BP. The tufa appears to have accumulated at a remarkably constant rate (14.4–16.5 cm 100 yr−1), except for the upper levels, where the rate increases fourfold. The succession has been divided into six local molluscan zones. An early assemblage consisting of ecologically tolerant species and those indicative of marshy grassland is replaced by a sequence of shade‐demanding taxa, reflecting the encroachment of woodland. Shaded conditions persist until the end of the sequence but the most hygrophilous elements decline after 5422±60 yr BP (zone 5), a change also reflected in the tufa lithology by the development of silty grey horizons. Notable species recovered from the tufa includeAcicula fusca, Vertigo substriata, V. alpestris, V. moulinsiana(all rare or unknown living in northern France).Hygromia limbata, a twentieth century introduction to Britain, was previously thought to be a relatively recent arrival in northern France, but its record at St Germain shows that it has been present in Normandy since 6500 yr BP.Azeca goodalli, another shade‐demanding species, appeared at St Germain much later, just after 4420±65 yr BP. Several other species present in the tufa, such asPomatias elegans, no longer live on the site, adding to the evidence for a distributional decline in Normandy and elsewhere. Perhaps the most noteworthy record is that ofLeiostyla anglica, between about 8500 yr BP and 5000 yr BP, because this constitutes its only Holocene occurrence from mainland Europe. Following this discovery it seems likely that further Holocene sites withL. anglicamay be found along the western seaboard of Europe connecting populations in Iberia with those of the British Isles. Copyright © 2004 John Wiley & Sons, Ltd.
Millennial‐scale climate variability in northwest Patagonia over the last 15 000 yr
Authors: Moreno Patricio I.
Published: January 2004

A pollen record from Lago Condorito (41°45'S, 73°07'W) shows prominent vegetation and climate changes at millennial time‐scales, superimposed on multimillennial trends in temperature and westerly activity in northwest Patagonia during the past 15 000 yr. The record shows that evergreen temperate rainforests have dominated the landscape over this interval, with floristic changes ranging from cold‐resistant North Patagonian forests with podocarp conifers to Valdivian forests with thermophilous, summer‐drought resistant species. The long‐term trend shows that cool‐temperate and humid conditions prevailed between 15 000 and 11 000 cal. yr BP, followed by an extreme warm and dry phase between 11 000 and 7600 cal. yr BP, and subsequent cooling events and increase in precipitation that peaked at ca. 5000 cal. yr BP, when Southern Hemisphere alpine glaciers achieved their first Neoglacial maximum. Modern conditions were established at ca. 1800 cal. yr BP, following a warm and dry phase between ca. 2900 and 1800 cal. yr BP. These results suggest that millennial‐scale climate variability during deglacial and post‐glacial times also affected the mid‐latitude region of the South Pacific, supporting the idea that changes in the tropical Pacific might be a key factor in the initiation and/or propagation of millennial‐scale climate variability at regional, hemispheric and global scales. Copyright © 2004 John Wiley & Sons, Ltd.
Aeolian activity in northern Amazonia: optical dating of Late Pleistocene and Holocene palaeodunes
Authors: Teeuw Richard M. , Rhodes Edward J.
Published: January 2004

Palaeodunes were examined on the eastern margin of the Rio Branco–Rupununi savanna, northeast Amazonia. Optical dating suggests that the onset of aeolian activity was between 17 000 and 15 000 yr ago, just after the Last Glacial Maximum. Both the palaeodune axes and modern dominant wind directions have northeast to east‐northeast directions, implying no significant shift in atmospheric circulation patterns over northeast Amazonia during the Late Pleistocene to Holocene. Major regional climate change events, such as the Younger Dryas, do not appear to have had any effect on the rates of aeolian deposition at the study site. Aeolian activity appears to have continued to the present day, showing a remarkably constant deposition rate of around 0.13 m kyr−1 initially, increasing smoothly to the present. Until more palaeodunes in northern Amazonia are dated, it is impossible to determine if this record of gradual aeolian deposition is a reliable regional palaeoclimate indicator, rather than being the result of local bioclimatic and geomorphological effects. Copyright © 2004 John Wiley & Sons, Ltd.
Quartz microtextures and microstructures owing to deformation of glaciolacustrine sediments in the northern Venezuelan Andes
Authors: Mahaney W. C. , Dirszowsky R. W. , Milner M. W. , Menzies J. , Stewart A. , Kalm V. , Bezada M.
Published: January 2004

Glaciolacustrine sediments, ranging in age from Early to Late Mérida (Wisconsinan) in sections in the northern Venezuelan Andes near Pedregal, were studied to assess the effect of small‐scale folding and faulting on the surface microtextures of individual grains. At site PED5, faulting of sediments beneath 35 m of Middle to Late Mérida glaciolacustrine, glaciofluvial and probable till deposits, has resulted in a maximum displacement of 1 m and many crushed sand grains are found along the shear zone. These dominantly quartz particles are typically smoothed and/or faceted with surface skins split from parent grains to produce adhering blade or wafer‐shaped coarse silts. Faulting with displacement of< 40 cm occurs in Late Mérida glaciolacustrine beds at sites PED13 and PED11, beneath ca. 1–5 m of sediment and is thought to result from the removal of lateral support during valley erosion and possibly seismic disturbance. Associated sediments exhibit a greater incidence of small‐scale fold structures and convoluted bedding but with similar numbers and types of crushed grains. All of the fault traces examined exhibit microstructural modifications, including microfaulting, folding and multiple domains associated with fluidisation and liquefaction. The microtextures described are distinct from those produced by glacial or glaciofluvial transport processes and potentially may be used to infer glaciotectonic or other post‐depositional disturbance of sediments. Rare euhedral quartz grains with distorted crystallographic axes may derive from the shear zone of the regional transform Boconó Fault, although many of these grains appear to be overprinted by glacial and/or recent deformation processes. Copyright © 2004 John Wiley & Sons, Ltd.
Histochemical characterisation of unextractable seed coat pigments and quantification of extractable lignin in the Brassicaceae
Authors: Marles MA Susan , Gruber Margaret Y
Published: January 2004

The differences determined by in situ histochemical staining and thioglycolic lignin analyses provided a new view of seed coat composition in a range of yellow‐ and brown‐seeded germplasm of the Brassicaceae. Unextractable seed coat pigments were composed of proanthocyanidin (condensed tannin) polymers. Anthocyanins were absent in all seed coat tissues. Proanthocyanidin was deposited over the entire seed coat in dark‐seeded germplasm and in patches in some yellow‐seeded germplasm. The seed coat and hilum of Crambe abyssinica cv Prophet and some yellow‐seeded accessions contained an unidentified, unreactive brown pigment. Several new pigmentation patterns, occurring as spots and patches and surrounding the hilum, became apparent from this analysis. Thioglycolic lignin was significantly lower in yellow‐seeded samples compared with the dark‐seeded accessions, and the majority of the lignin occurred in the seed coat. These discoveries provide new and useful data for plant breeders and indicate the need to use more detailed analytical methods in breeding programmes that have the goal of improving seed meal quality by reducing fibre and phenolics. Copyright © 2004 Society of Chemical Industry
Grain mineral concentrations and yield of wheat grown under organic and conventional management
Authors: Ryan MH , Derrick JW , Dann PR
Published: January 2004

On the low‐P soils in southeastern Australia, organic crops differ from conventional ones primarily in the use of relatively insoluble, as opposed to soluble, P fertilisers and in the non‐use of herbicides. As organic management, particularly elimination of soluble fertilisers, is often claimed to enhance grain mineral concentrations, we examined grain from wheat on paired organic and conventional farms in two sets of experiments: (1) four pairs of commercial crops (1991–1993); and (2) fertiliser experiments on one farm pair where nil fertiliser was compared with 40 kg ha−1 of P as either relatively insoluble reactive phosphate rock or more soluble superphosphate (1991 and 1992). All wheat was grown following a 2–6 year legume‐based pasture phase. Both conventional management and the superphosphate treatment greatly increased yields but reduced colonisation by mycorrhizal fungi. While only minor variations occurred in grain N, K, Mg, Ca, S and Fe concentrations, conventional grain had lower Zn and Cu but higher Mn and P than organic grain. These differences were ascribed to: soluble P fertilisers increasing P uptake but reducing mycorrhizal colonisation and thereby reducing Zn uptake and enhancing Mn uptake; dilution of Cu in heavier crops; and past lime applications on the organic farm decreasing Mn availability. These variations in grain minerals had nutritional implications primarily favouring the organic grain; however, organic management and, specifically, elimination of soluble fertilisers did not induce dramatic increases in grain mineral concentrations. In addition, organic management was coupled with yield reductions of 17–84 per cent due to P limitation and weeds. The impact of large regional variations in the characteristics of organic and conventional systems on the general applicability of the results from this study and other similar studies is discussed. Copyright © 2004 Society of Chemical Industry
Solid state fermentation process for producing chickpea (Cicer arietinum L) tempeh flour. Physicochemical and nutritional characteristics of the product
Authors: Reyes‐Moreno C , Cuevas‐Rodríguez EO , Milán‐Carrillo J , Cárdenas‐Valenzuela OG , Barrón‐Hoyos J
Published: January 2004

Solid state fermentation (SSF) represents a technological alternative for processing a great variety of legumes and/or cereals to improve their nutritional quality and to obtain edible products with palatable sensorial characteristics. The objectives of this work were (1) to determine the best combination of SSF process variables (fermentation temperature FT/fermentation time Ft) for producing chickpea tempeh flour and (2) to characterise the physicochemical and nutritional properties of the product. Response surface methodology was applied as optimisation technique over three response variables: in vitro protein digestibility (PD), true protein (TP) and water absorption index (WAI). A central composite experimental design with two factors and five levels was used. The process variables FT and Ft had variation levels of 31–36 °C and 48–72 h respectively. Rhizopus oligosporus (1 × 109 spores l−1 in distilled water) was used as starter. Prediction models for response variables were developed as a function of process variables. A conventional graphical method was applied to obtain maximum PD, TP and WAI. Contour plots of each of the response variables were superimposed to obtain a contour plot for observation and selection of the best combination of FT (34.9 °C) and Ft (51.3 h) for producing of chickpea tempeh, which was dried (52 °C, 24 h) and milled to pass through an 80‐US mesh (0.180 mm) screen to obtain optimised chickpea tempeh flour. This flour had higher (p ≤ 0.05) TP (25.7 vs 19.7% dry matter (DM)), total colour difference (30.3 vs 16.7), WAI (4.18 vs 2.15 kg gel kg−1 DM), available lysine (42.7 vs 30.4 g kg−1 protein) and PD (83.2 vs 72.2%) and lower lipid content (2.6 vs 6.1% DM), phytic acid (1.1 vs 10.85 g kg−1 DM), tannins (2.65 vs 21.95 g catechin kg−1 DM) and pH (5.9 vs 6.3) than raw chickpea flour. Copyright © 2004 Society of Chemical Industry
Effect of nitrate/nitrite on the quality of sausage (sucuk) during ripening and storage
Authors: Bozkurt Hüseyin , Erkmen Osman
Published: January 2004

The effects of nitrate/nitrite on the microbial and chemical properties and sensory quality of Turkish‐style sausage (sucuk) were investigated during 15 days of ripening and 45 days of storage. Aerobic plate count, mould and yeast count, pH, 2‐thiobarbituric acid value, residual nitrite level, nitrosomyoglobin conversion and sensory characteristics (flavour, colour and cutting scores) were monitored. Aerobic plate count increased (P < 0.05) during the first 8 days of ripening and decreased (P < 0.05) during further ripening and storage. Mould and yeast count increased (P < 0.05) during the first 4 days of ripening and decreased (P < 0.05) during further ripening and storage. Overall sensory quality increased (P < 0.05) during the first 12 days of ripening and decreased (P < 0.05) during further ripening and storage. Increasing the nitrate/nitrite concentration increased (P < 0.05) the overall sensory quality. During the first 4 days of ripening, the pH of all sausages decreased (P < 0.05) from 5.98 to 4.53–4.81, owing to the action of lactic acid bacteria. Residual nitrite level decreased (P < 0.05) sharply during the first 8 days of ripening, from 150 to about 2 mg kg−1 in sausage samples B3 (prepared with 150 mg kg−1 nitrite, 300 mg kg−1 nitrate and starter culture) and from 75 to about 1 mg kg−1 in samples B2 (prepared with 75 mg kg−1 nitrite, 150 mg kg−1 nitrate and starter culture). The conversion of haem pigments to nitrosomyoglobin increased (P < 0.05) during the first 12 days of ripening and decreased (P < 0.05) during further ripening and storage. Copyright © 2004 Society of Chemical Industry
LC‐MS identification of anthocyanins in boysenberry extract and anthocyanin metabolites in human urine following dosing
Authors: Cooney Janine M , Jensen Dwayne J , McGhie Tony K
Published: January 2004

The anthocyanin composition of boysenberry (Rubusloganbaccus × baileyanus Britt) extract was determined by LC‐ESI‐MS. Four anthocyanins were identified, all comprising a cyanidin‐anthocyanidin‐type skeleton. The two major components were identified as the disaccharide cyanidin‐3‐O‐sophoroside and the monosaccharide cyanidin‐3‐O‐glucoside. The two less abundant components were identified as the rutinosides, cyanidin‐3‐O‐2G‐glucosylrutinoside and cyanidin‐3‐O‐rutinoside, respectively. These same four anthocyanins were also detected in human urine following a dosing study with boysenberry extract indicating that glycosylated anthocyanins can be absorbed from the gut and excreted intact in the urine. Several anthocyanin metabolites were also detected in the urine and were identified by LC‐ESI‐MS as monoglucuronides of peonidin, cyanidin and pelargonidin. The results suggest that anthocyanins consumed as part of a diet are bioavailable and are present as intact or metabolized forms in the body. Copyright © 2004 Society of Chemical Industry
A research note: the potential for transfer of Salmonella from irrigation water to tomatoes
Authors: Jablasone Julietta , Brovko Lubov Y , Griffiths Mansel W
Published: January 2004

The transmission of Salmonella Enteritidis from soil to fruit by contaminated irrigated water was studied using 20 patio tomato plants. In order to track the presence of Salmonella in the soil and plants a luminescent strain transformed with the full luxCDABE gene cassette from Photorhabdus luminescens was used. The tomato plants were irrigated every other day by direct application of water containing Salmonella Enteritidis (105 CFU ml−1) to the soil. Samples of soil, stem, leaf and fruit were taken weekly and assayed for Salmonella by plating onto Luria Bertani agar containing 50 µg ml−1 ampicillin. There was a significant difference (P < 0.05) in Salmonella counts from soils sampled during the course of the study. No Salmonella were recovered from the leaf, stem, and fruit samples taken from the tomato plants. This indicates that, under these test conditions, watering with contaminated water directly into the soil does not result in the transmission of Salmonella, and possibly other pathogens, to tomatoes. Copyright © 2004 Society of Chemical Industry
A model of non‐isothermal degradation of nutrients, pigments and enzymes
Authors: Corradini Maria G , Peleg Micha
Published: January 2004

Published isothermal degradation curves for chlorophyll A and thiamine in the range 100–150 °C and the inactivation curves of polyphenol oxidase (PPO) in the range 50–80 °C could be described by the model C(t)/C0 = exp[−b(T)tn] where C(t) and C0 are the momentary and initial concentrations, respectively, b(T) a temperature dependent ‘rate parameter’ and n, a constant. This suggested that the temporal degradation/inactivation events of all three had a Weibull distribution with a practically constant shape factor. The temperature dependence of the ‘rate parameter’ could be described by the log logistic model, b(T) = loge[1 + exp[k(T − Tc)], where Tc is a marker of the temperature level where the degradation/inactivation occurs at a significant rate and k the steepness of the b(T) increase once this temperature range has been exceeded. These two models were combined to produce a non‐isothermal degradation/inactivation model, similar to one recently developed for microbial inactivation. It is based on the assumption that the local slope of the non‐isothermal decay curve, ie the momentary decay rate, is the slope of the isothermal curve at the momentary temperature at a time that corresponds to the momentary concentration of the still intact or active molecules. This model, in the form of a differential equation, was solved numerically to produce degradation/inactivation curves under temperature profiles that included heating and cooling and oscillating temperatures. Such simulations can be used to assess the impact of planned commercial heat processes on the stability of compounds of nutritional and quality concerns and the efficacy of methods to inactivate enzymes. Simulated decay curves on which a random noise was superimposed were used to demonstrate that the degradation/inactivation parameters, k and Tc, can be calculated directly from non‐isothermal decay curves, provided that the validity of the Weibullian and log logistic models and the constancy of the shape factor n could be assumed. Copyright © 2004 Society of Chemical Industry
Low sensitivity of the touch imprint cytology of the sentinel lymph node in breast cancer patients—results of a large series
Authors: Zgajnar Janez , Frkovic‐Grazio Snjezana , Besic Nikola , Hocevar Marko , Vidergar‐Kralj Barbara , Gerljevic Andrej , Pogacnik Ana
Published: January 2004

Background and Objectives

Touch imprint cytology (TIC) was reported to be a sensitive method of intraoperative sentinel lymph node (SLN) assessment. The objective of our study was to assess the value of the TIC as an intraoperative SLN evaluation method and to determine a subgroup of patients in whom TIC should not be indicated.

Methods

In 250 breast cancer patients with SLN biopsy, TIC of SLNs was performed intraoperatively. The results of TIC were compared to the final histopathological analysis of SLNs. A subgroup analysis of the TIC value was performed with regard to the tumor size.

Results

SLN metastases were found in 102/250 patients (41%). Two cases were false positive. The sensitivity of TIC was 34%, specificity 98.6%, accuracy 72%, negative predictive value 69%, and positive predictive value 95%. TIC was significantly more sensitive to detect macrometastases (32/43) compared to micrometastases or ITC (3/59) (P < 0.001). TIC was positive in only 5% (4/77) in T < 10 mm tumors compared to 18% (31/168) in T > 10 mm (P = 0.01).

Conclusions

TIC is a simple, quick, and sensitive method of intraoperative SLNs evaluation for the presence of the macrometastases. TIC has a very limited value in detecting micrometastases and no value in detecting ITC. TIC may not be indicated in T1a + b tumors. J. Surg. Oncol. 2004;85:82–86. © 2004 Wiley‐Liss, Inc.
Autofluorescence Spectrofluorometry of central nervous system (CNS) neuromediators
Authors: Crespi Francesco , Croce Anna C. , Fiorani Sabrina , Masala Barbara , Heidbreder Christian , Bottiroli Giovanni
Published: January 2004

Background and Objectives

Changes in the neurotransmitter 5‐hydroxytriptamine (5‐HT) are related to psychiatric diseases such as depression and anxiety. In this study, 5‐HT autofluorescence properties were investigated in solution and in biological tissues.

Study Design/Materials and Methods

Spectrofluorometric characterization was performed on ex vivo samples (tissue sections, homogenates) of the 5‐HT‐rich brain region hippocampus from rats untreated or treated to affect endogenous 5‐HT levels; in vivo, with a 50 ⊘ optic fiber probe positioned via stereotaxis.

Results

5‐HT exhibited minor excitation and emission bands at wavelengths longer than the well known excitation and emission bands in the UV region, 250–320 nm. Spectrofluorometric measurements under 366 nm excitation on homogenates supplied with 5‐HT or belonging to treated rats revealed spectral alterations attributable to changes in the amount of 5‐HT. Ex vivo and in vivo autofluorescence data were consistent with those obtained by conventional voltammetry.

Conclusions

Autofluorescence spectroscopy potential is confirmed as a suitable technique for the direct measurement of neurotransmitters. Lasers Surg. Med. 34:39–47, 2004. © 2004 Wiley‐Liss, Inc.
MR thermometry‐based feedback control of laser interstitial thermal therapy at 980 nm
Authors: McNichols Roger J. , Gowda Ashok , Kangasniemi Marko , Bankson James A. , Price Roger E. , Hazle John D.
Published: January 2004

Background and Objectives

The goal of this study was to explore the feasibility of magnetic resonance thermal imaging (MRTI)‐based feedback control of intracerebral laser interstitial thermal therapy (LITT), using a computer workstation and 980‐nm diode laser interfaced to an MR scanner.

Study Design/Materials and Methods

A computer‐controlled laser thermal therapy system was used to produce 12 ex vivo lesions in 3 canine and porcine brains and 16 in vivo lesions in 6 canines with diffusing tip fiberoptic applicators and energies from 54 to 900 J. MRTI predictions of thermal damage were correlated with histopathologic analysis.

Results

Under feedback control, no carbonization, vaporization, or applicator damage was observed. MRTI‐based prediction of thermal dose was not significantly different from histological evaluation of achieved thermal necrosis.

Conclusions

The computer‐controlled thermal therapy system was effective at regulating heating, eliminating carbonization and vaporization, and protecting fiberoptic applicators. MRTI estimation of thermal dose accurately predicted achieved thermal necrosis. Lasers Surg. Med. 34:48–55, 2004. © 2004 Wiley‐Liss, Inc.
Photodynamic endometrial ablation for the treatment of dysfunctional uterine bleeding: A preliminary report
Authors: Degen Andrea F. , Gabrecht Tanja , Mosimann Laurent , Fehr Mathias K. , Hornung René , Schwarz Viola A. , Tadir Yona , Steiner Rolf A. , Wagnières Georges , Wyss Pius
Published: January 2004

Background and Objectives

To evaluate feasibility and functional effects of photodynamic endometrial ablation (PEA) in patients.

Study Design/Patients and Methods

A total of 15 PEAs has been performed in 11 patients using topically applied 5‐aminolevulinic acid (ALA) solutions and a balloon‐light diffuser (160 J/cm2, 635 nm). Uterine bleeding intensity has been determined on a daily basis 3 months prior to and up to 6 months after endometrial ablation using an analogous scale scoring from 1 (spotting) to 6 U (severe bleeding). Statistical analysis by unpaired Student's t‐test.

Results

The mean number of bleeding units per cycle (n = 44) was 35.7 prior to PEA. The decrease in bleeding units was significant for the months 1–3 (24.4 U per cycle; P = 0.03), but not for the months 4–6 (25.9 U; P = 0.11) following PEA.

Conclusions

PEA is feasible and provides a significant short‐term reduction of uterine bleeding. Lasers Surg. Med. 34:1–4, 2004. © 2004 Wiley‐Liss, Inc.
Effect of 5‐aminolevulinic acid‐mediated photodynamic therapy on MCF‐7 and MCF‐7/ADR cells
Authors: Tsai Tsuimin , Hong Ruey‐Long , Tsai Jui‐Chang , Lou Pei‐Jen , Ling I‐Fang , Chen Chin‐Tin
Published: January 2004

Background and Objectives

Photodynamic therapy (PDT) has been proposed as an alternative approach in overcoming multidrug resistance (MDR) phenotype. To verify whether 5‐aminolevulinic acid (ALA)‐mediated PDT is effective in MDR cells, we studied the protoporphyrin IX (PpIX) content, intracellular localization, and phototoxicity in human breast cancer cells MCF‐7 and derived MDR subline, MCF‐7/ADR.

Study Design/Materials and Methods

The fluorescence kinetics of ALA‐induced PpIX was evaluated by spectrofluorometer. The phototoxicity of MCF‐7 and MCF‐7/ADR cells was determined by tetrazolium (MTT) assays and clonogenic assay. Furthermore, Annexin V and propidium iodide (PI) binding assays were performed to analyze the characteristics of cell death after ALA–PDT.

Results

MCF‐7/ADR accumulated a lower level of PpIX as compared to parental MCF‐7 cells. Significant phototoxicity was observed in MCF‐7 and increased in a fluence‐dependent manner with LD50 around 8 J/cm2. Compared to its parental counterpart, MCF‐7/ADR cells were less sensitive to ALA photodynamic treatment and PDT‐induced cytotoxicity did not increase in a dose responsive manner as the concentration of ALA increased or the fluence of light increased. ALA–PDT was less effective for MCF‐7/ADR cells than MCF‐7 cells even under the condition when these two cell lines contained the similar amounts of PpIX.

Conclusions

These results indicate that, except for the MDR related characteristics, MCF‐7/ADR cells might possess intrinsic mechanisms that render them less sensitive to ALA–PDT induced phototoxicity. Lasers Surg. Med. 34:62–72, 2004. © 2004 Wiley‐Liss, Inc.
Infrared imaging of subcutaneous veins
Authors: Zharov Vladimir P. , Ferguson Scott , Eidt John F. , Howard Paul C. , Fink Louis M. , Waner Milton
Published: January 2004

Background and Objectives

Imaging of subcutaneous veins is important in many applications, such as gaining venous access and vascular surgery. Despite a long history of medical infrared (IR) photography and imaging, this technique is not widely used for this purpose. Here we revisited and explored the capability of near‐IR imaging to visualize subcutaneous structures, with a focus on diagnostics of superficial veins.

Study Design/Materials and Methods

An IR device comprising a head‐mounted IR LED array (880 nm), a small conventional CCD camera (Toshiba Ik‐mui, Tokyo, Japan), virtual‐reality optics, polarizers, filters, and diffusers was used in vivo to obtain images of different subcutaneous structures. The same device was used to estimate the IR image quality as a function of wavelength produced by a tunable xenon lamp‐based monochrometer in the range of 500–1,000 nm and continuous‐wave Nd:YAG (1.06 μm) and diode (805 nm) lasers.

Results

The various modes of optical illumination were compared in vivo. Contrast of the IR images in the reflectance mode was measured in the near‐IR spectral range of 650–1,060 nm. Using the LED array, various IR images were obtained in vivo, including images of vein structure in a pigmented, fatty forearm, varicose leg veins, and vascular lesions of the tongue.

Conclusion

Imaging in the near‐IR range (880–930 nm) provides relatively good contrast of subcutaneous veins, underscoring its value for diagnosis. This technique has the potential for the diagnosis of varicose veins with a diameter of 0.5–2 mm at a depth of 1–3 mm, guidance of venous access, podiatry, phlebotomy, injection sclerotherapy, and control of laser interstitial therapy. Lasers Surg. Med. 34:56–61, 2004. © 2004 Wiley‐Liss, Inc.
Asymptotic decay estimates for the repulsive Schrödinger–Poisson system
Authors: Sánchez Óscar , Soler Juan
Published: January 2004

In this paper the time decay rates for the solutions to the Schrödinger–Poisson system in the repulsive case are improved in the context of semiconductor theory. Upper and lower estimates are obtained by using a norm involving the potential energy and the dispersion equation. In the attractive case some examples, based on the Galilean invariance, are proposed showing that the solutions does not have a dispersive character. Copyright © 2004 John Wiley & Sons, Ltd.
Homogenization of a composite medium with a thermal barrier
Authors: Mabrouk Mongi , Hassan Samadi
Published: January 2004

In this work, we consider a heat transfer problem between two periodic connected media exchanging a heat flux throughout their common interface. The interfacial exchange coefficient λ is assumed to tend to zero or to infinity following a rate λ=λ(ε) when the size εof the basic cell tends to zero. Three homogenized problems are determined according to the value of δ=limε→0λ/ε. Copyright © 2004 John Wiley & Sons, Ltd.
An age‐dependent population equation with delayed birth process
Authors: Piazzera Susanna
Published: January 2004

Within a semigroup framework, we discuss well posedness and qualitative behaviour of an age‐dependent population equation with delay in the birth process. Using positivity and Perron–Frobenius theory we obtain an explicit stability criterion. Copyright © 2004 John Wiley & Sons, Ltd.
Existence and stability of global regular solutions for a dusty gas model
Authors: Doronin G. G. , Larkin N. A. , De Souza A. J.
Published: January 2004

The initial and initial‐boundary value problems for the two‐phase model of ‘fluid‐solid particles’ media are considered. Existence, uniqueness and exponential decay of global strong solutions for small initial data are proved. Copyright © 2004 John Wiley & Sons, Ltd.
Unconditional non‐linear stability for a fluid of third grade
Authors: Budu Paula
Published: January 2004

The thermal convection in a layer of a third grade fluid is investigated, with viscosity being a general function of temperature. We develop a non‐linear stability analysis and prove that unconditional non‐linear stability criterion is achieved using a natural energy approach. This shows that, in some sense, the equations for a fluid of third grade are preferable to those for a fluid of second grade or a dipolar fluid. Copyright © 2004 John Wiley & Sons, Ltd.
Hydromagnetic rotating flow of a fourth‐order fluid past a porous plate
Authors: Wang Yongqi , Hayat Tasawar
Published: January 2004

The rotating flow in the presence of a magnetic field is a problem belonging to hydromagnetics and deserves to be more widely studied than it has been to date. In the non‐linear regime the literature is scarce. We develop the governing equations for the unsteady hydromagnetic rotating flow of a fourth‐order fluid past a porous plate. The steady flow is governed by a boundary value problem in which the order of differential equations is more than the number of available boundary conditions. It is shown that by augmenting the boundary conditions based on asymptotic structures at infinity it is possible to obtain numerical solutions of the nonlinear hydromagnetic equations. Effects of uniform suction or blowing past the porous plate, exerted magnetic field and rotation on the flow phenomena, especially on the boundary layer structure near the plate, are numerically analysed and discussed. The flow behaviours of the Newtonian fluid and second‐, third‐ and fourth‐order non‐Newtonian fluids are compared for the special flow problem, respectively. Copyright © 2004 John Wiley & Sons, Ltd.
Regulatory light chain phosphorylation increases eccentric contraction–induced injury in skinned fast‐twitch fibers
Authors: Childers Martin K. , McDonald Kerry S.
Published: January 2004

During contraction, activation of Ca2+/calmodulin–dependent myosin light chain kinase (MLCK) results in phosphorylation of myosin's regulatory light chain (RLC), which potentiates force and increases speed of force development over a wide range of [Ca2+]. We tested the hypothesis that RLC phosphorylation by MLCK mediates the extent of eccentric contraction–induced injury as measured by force deficit in skinned fast‐twitch skeletal muscle fibers. Results indicated that RLC phosphorylation in single skinned rat psoas fibers significantly increased Ca2+ sensitivity of isometric force; isometric force from 50 ± 16 to 59 ± 18 kN/m2 during maximal Ca2+ activation; peak absolute power output from 38 ± 15 to 48 ± 14 nW during maximal Ca2+ activation; and the magnitude of contraction‐induced force deficit during maximal (pCa 4.5) activation from 26 ± 9.8 to 35 ± 9.6%. We conclude that RLC phosphorylation increases force deficits following eccentric contractions, perhaps by increasing the number of force‐generating cross‐bridges. Muscle Nerve 29: 313–317, 2004
Matrix metalloproteinases and skeletal muscle: A brief review
Authors: Carmeli Eli , Moas Miri , Reznick Abraham Z. , Coleman Raymond
Published: January 2004

Matrix metalloproteinases (MMPs) are a family of zinc‐ dependent proteolytic enzymes that function mainly in the extracellular matrix, where they contribute to the development, functioning, and pathology of a wide range of tissues. This mini‐review describes the MMPs and tissue inhibitors of MMPs (TIMPs) in skeletal muscle, and considers their involvement in muscle development, ischemia, myonecrosis, angiogenesis, denervation, exercise‐induced injuries, disuse atrophy, muscle repair and regeneration, and inflammatory myopathies and dystrophies. Despite the very limited information currently available on MMPs and their inhibitors in skeletal muscle, it is becoming increasingly clear that they have important physiological functions in maintenance of the integrity and homeostasis of muscle fibers and of the extracellular matrix. Understanding the roles of MMPs and TIMPs may lead to the development of new drug‐related treatments for various muscle disorders based on suppression or upregulation of their expression. Muscle Nerve 29: 191–197, 2004
Reproducibility of statistical motor unit number estimates in amyotrophic lateral sclerosis: Comparisons between size‐ and number‐weighted modifications
Authors: Kwon Ohyun , Lee Kwang‐Woo
Published: January 2004

Motor unit number estimations (MUNEs) can directly assess motor unit populations in muscle and quantify the degree of physiological or pathological motor unit degeneration. A high degree of reproducibility and reliability is required of any effective quantitative tool. MUNE is being increasingly applied clinically, and statistical MUNE has several advantages over alternative techniques. Nevertheless, the optimal method of applying statistical MUNE with respect to its reproducibility has not been established. We performed statistical MUNE by selecting the most compensated compound muscle action potential (CMAP) area as a test area and modified the results obtained by using the weighted mean surface‐recorded motor unit potential (SMUP). MUNE measurements made in patients with amyotrophic lateral sclerosis (ALS) showed better reproducibility after incorporating the size‐weighted modification. Therefore, we suggest that the size‐weighted MUNE in combination with the selection of testing “neurogenically compensated” CMAP areas is a more reliable method of statistical MUNE analysis in ALS patients. Muscle Nerve 29: 211–217, 2004
Temporal discrimination threshold on various parts of the body
Authors: Hoshiyama Minoru , Kakigi Ryusuke , Tamura Yohei
Published: January 2004

The temporal discrimination threshold (TDT) of various parts of the body was investigated in 35 healthy volunteers, and the effect of aging on the TDT was studied in 80 subjects (aged 18–82 years). Ascending (ATDT) and descending (DTDT) TDT values were measured in 13 areas using a pair of electrical stimuli. Both ATDT and DTDT differed significantly among the body parts (P < 0.01, one‐way repeated ANOVA), and the TDT was shortest on the index finger and longest on the lower leg, where it was approximately 156% of that on the finger. There was no difference of the TDT value with gender or between sides. There was no effect of aging on the TDT in subjects aged 18–64 years, but the value was prolonged in subjects over 65 years. We suggest that the TDT difference among body parts is mainly due to the difference in sensory processes in the central nervous system, and that it may provide information about changes in the system related to aging. Muscle Nerve 29: 243–247, 2004