bluuebunny/crossref_metadata_2025 huggingface dataset:
Three‐dimensional reconstruction of the mucosa from sequential sections of biopsy specimens of patients with ulcerative colitis: Relationship between crypt structure and vascular architecture
Authors: Furukawa Hiroo , Inoue Fumihiko , Miyake Naoki , Moriyasu Takayuki , Moriti Hisako , Saiga Tatuyosi
Published: March 2004

Background:  In a previous paper, the stereographic reconstruction of the crypt structure of ulcerative colitis using the RATOCK System was described. The relationship between the blood vessels and the crypt structure is the focus of the current paper, using two kinds of tissue staining color in which the color differs. Stereographic images make the relationship between the crypt structure and blood vessel distribution understandable at a glance.

Methods:  The methods used here are identical to those described in a previous paper. In the present paper, five cases of ulcerative colitis (UC) are examined. Biopsy specimens were obtained from the diseased, normal, and transitional zones (the area between the normal and diseased zones) from each patient. Three‐dimensional reconstruction was created using TRI for Windows (RATOC System Tokyo, Japan) software. In the present paper, two kinds of dyeing method between H&E and monoclonal antibody staining of the tissue was used. It was proven that the distribution of gland and blood vessel is very clear in the 3‐D reconstruction shown.

Results:  (i) The blood vessels in the normal zones run parallel to the crypt in a regular manner and are almost identical to one another in diameter. (ii) In the transitional and diseased zones, the blood vessels show no clear direction and produce many branches without any apparent order. The blood vessels are, moreover, irregular in diameter. (iii) In short, clear parallelism is lost in both the transitional and diseased zones.

Conclusion:  Stereographic reconstruction of endoscopically obtained biopsy specimens of UC‐affected tissues makes it possible to understand at a glance the distribution of blood vessels and their relationship to crypts. The relationship of these was clarified by the combined use of two kinds of dyeing method with three‐dimensional reconstruction.
Correlation between serum pepsinogen levels and gastric mucosal histological findings before and after Helicobacter pylori eradication therapy
Authors: Kawai Takashi , Kawakami Kohei , Kudo Taku , Takei Kazuo , Moriyasu Fuminori , Takagi Yuu , Aoki Tatsuya , Koyanagi Yasuhisa , Serizawa Hiromi , Rinbara Emiko , Noguchi Masahisa , Sasatsu Masanori
Published: March 2004

Background:  Helicobacter pylori causes chronic gastritis and is also associated with many other gastrointestinal diseases. The incidence of gastric cancer is thought to vary according to the degree and topography of chronic gastritis. Histological findings of specimens obtained at endoscopy are therefore important. In the present study, we investigated the correlation between these histological findings and serum pepsinogen (PG) levels.

Methods:  Helicobacter pylori eradication therapy was conducted in 100 H. pylori‐positive patients. Endoscopies were performed prior to, and 2 months after, eradication therapy; gastric mucosal biopsies were taken from the antrum and corpus. Helicobacter pylori infection was diagnosed using the rapid urease test, culture and histology. Using the Updated Sydney System, histological findings of inflammation, activity, atrophy and intestinal metaplasia were each graded. Blood was taken on the same two occasions for determination of serum levels of PG I and II.

Results:  Levels of PG I were highest in association with antrum‐predominant gastritis (APG), followed in order by pangastritis (PAN) and corpus‐predominant gastritis (CPG), with a significant difference between APG and CPG. No correlations were seen between PG II levels and gastritis topography. Examination of the relationship between PG levels and histological findings revealed significant correlations between PG I levels after eradication atrophy and intestinal metaplasia in the gastric corpus. No significant correlations were seen between PG II levels and before or after eradication histological findings.

Conclusion:  Our results indicate that serum PG levels may be a useful indicator of before‐eradication gastritis topography and after‐eradication gastric atrophy in the gastric corpus.
Successful endoscopic removal of a duodenal adenoma occurring in Brunner's gland hyperplasia
Authors: Doi Kosei , Tada Shuji , Fujimoto Takahisa , Ohwan Tomohisa , Ueno Naotsugu , Suko Hironobu , Kamio Takihiro , Matsumoto Takayuki , Iida Mitsuo
Published: March 2004

A case of duodenal neoplasm in the second portion of the duodenum is presented. Endoscopically, the lesion was characterized by a broad‐based, submucosal tumor‐like protrusion with a shallow central depression. The lesion was successfully removed by endoscopic mucosal resection. Histological examination of the resected specimen revealed the lesion to be composed of Brunner's gland hyperplasia in the submucosal layer and adenomatous glands in the mucosa. Our case suggests that neoplastic transformation possibly occurs in Brunner's gland hyperplasia.
Case of early ampullary cancer treated by endoscopic papillectomy
Authors: Ito Kei , Fujita Naotaka , Noda Yutaka , Kobayashi Go , Kimura Katsumi , Horaguchi Jun , Takasawa Osamu
Published: March 2004

We herein report a case of ampullary cancer in a 65‐year‐old man who underwent endoscopic papillectomy. Duodenoscopy revealed an exposed‐type tumor mass at the ampulla of Vater. Histology of the biopsy specimen demonstrated well‐differentiated adenocarcinoma. Endoscopic ultrasonography and intraductal ultrasonography showed a hypoechoic mass limited to the ampulla of Vater (clinical stage, T1). Endoscopic papillectomy was performed after informed consent was obtained. Histological examination of the resected specimen revealed adenocarcinoma limited to the ampulla of Vater (final stage, pT1). Both accurate preoperative T staging and proper histological evaluation of the resected specimen appear to justify endoscopic treatment of early ampullary cancer.
Case of chronic schistosomiasis mansoni with portal hypertension
Authors: Hayashi Seishu , Ohtake Hiroo
Published: March 2004

The patient was a 30‐year‐old male from Guinea, who had been living in Japan for 10 years. He was diagnosed as having chronic active schistosomiasis mansoni with portal hypertension. Ultrasonography of the liver showed wide high‐echo bands in the hilus of the portal vein, and its central and peripheral branches. Selective splenic arteriography demonstrated enlargement of the portal vein trunk and amputation of large peripheral branches of portal vein. On peritoneoscopy, the liver surface showed medium‐sized block‐like formations separated by irregular linear septa with mild to moderate depression, and many tiny white structures were observed on the liver surface. On magnifying peritoneoscopy, some irregular abnormal veins were observed, and normal peripheral branches of the portal vein were almost diminished on the liver surface. Wide white structures assumed to be thickened medium‐sized branches of the portal vein were also observed on the deeper part of the liver surface. Histological examination of the liver biopsy specimens revealed broad collagenous fibrosis of the portal area with slight infiltration of eosinophils, a few schistosomal ova, diminishing of the peripheral branches of the portal vein and dilatation of abnormal vessels in some portal tracts.
Remarkable effectiveness of endoscopic argon plasma coagulation against diffuse antral vascular ectasia
Authors: Sou Suketo , Nagahama Takashi , Nomura Hideyuki , Matsubara Fujio , Tanaka Hideyoshi , Matsui Toshiyuki , Yao Tsuneyoshi
Published: March 2004

A 49‐year‐old woman had been suffering from chronic glomerulonephritis and serious anemia (Hb 5.0 g/dL) since January 1998 and had frequent blood transfusions. Epigastric distress appeared in January 2001, and she was referred to Shin‐Kokura Hospital on 6 July of the same year. Upper gastrointestinal endoscopy revealed mucosal redness circumferentially encompassing the area from the antrum of the stomach to the prepyloric ring, and telangiectasia was observed at a proximal view over the affected part. A diagnosis of diffuse antral vascular ectasia (DAVE) was made after a histological study by biopsy revealed telangiectasia and stasis at the lamina propria. Endoscopic cauterization was conducted by argon plasma coagulation (APC) in three consecutive sessions. Endoscopy and biopsy carried out at 1 month after completion of the APC therapy showed that the lesion had completely healed. Subsequently, the anemia improved. The results suggest that APC is a reliable and safe method of endoscopic treatment for diffuse mucosal hemorrhagic lesion, including DAVE.
Capsule endoscopic features of Crohn's disease
Authors: Reddy D Nageshwar , Kaffes Arthur J , Sriram Parupudi VJ , Rao G Venkat
Published: March 2004

Background:  Crohn's disease (CD) is becoming increasingly recognized in Indian patients. As this disease often affects the small bowel, capsule endoscopy can help diagnose this disease and add valuable information regarding the extent of the disease. Our aim is to report our experience with the wireless capsule endoscope in patients with either known or suspected CD.

Methods:  Patients referred for capsule endoscopy with known or suspected CD were studied. All patients underwent precapsule endoscopy colonoscopy and small bowel series examination. After an overnight fast and bowel preparation, the capsule was ingested and the data were recorded for 8 h on the external recording device. A gastroenterologist experienced in reading capsule endoscopy interpreted images.

Results:  Eleven patients (mean age 42 years [range 14–70], 7 males) underwent capsule examination. Seven patients had symptoms suggestive of CD with no precapsule evidence of the disease, one had suspected small bowel pseudo‐obstruction and three had known CD. All patients had lesions in the small intestine consistent with CD. Two patients had strictures that led to a retained capsule, despite precapsule small bowel series.

Conclusions:  Capsule endoscopy is emerging as a small bowel imaging modality that can greatly assist in making the diagnosis of CD. Small bowel radiology is unreliable in excluding strictures that may cause capsule retention.
Bleeding from foveolar hyperplasia developing on a gastrointestinal stromal tumor of the stomach
Authors: Miyake Kazumasa , Tatsuguchi Atsushi , Tachibana Mikiko , Kusunoki Masanobu , Shinji Yoko , Shinoki Kei , Hiratsuka Tetsuro , Nagata Kazuhiro , Nishigaki Hitoshi , Futagami Seiji , Wada Ken , Tsukui Taku , Yoshiyuki Toshiro , Tokunaga Akira , Tajiri Takashi , Sakamoto Choitsu
Published: March 2004

A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.
Endoscopic submucosal dissection using sodium hyaluronate for large superficial tumors in the colon
Authors: Yamamoto Hironori , Sunada Keijiro , Miyata Tomohiko , Sekine Yutaka , Kita Hiroto , Iwamoto Michiko , Yano Tomonori , Onishi Nobuki , Kuno Akiko , Ido Kenichi , Sugano Kentaro
Published: March 2004

Endoscopic submucosal dissection is becoming popular for large superficial gastric cancer in Japan. However, it is considered difficult in the colon because the colonic wall is much thinner than the gastric wall. We use several devices to overcome this difficulty and have made it feasible in the colon as well. Submucosal injection of sodium hyaluronate is used to maintain sufficient thickening of the submucosal tissue and a small‐caliber‐tip or regular cylindrical transparent hood is used to open up the incised mucosa as a substitute for countertraction. In this method, not only the lateral margin, but the vertical margin of the resection can also be determined precisely because submucosal incision is carried out under direct visualization of the submucosal tissue.
Copepods act as a switch between alternative trophic cascades in marine pelagic food webs
Authors: Stibor Herwig , Vadstein Olav , Diehl Sebastian , Gelzleichter Anna , Hansen Thomas , Hantzsche Florian , Katechakis Alexis , Lippert Bettina , Løseth Kjetil , Peters Claudia , Roederer Wendy , Sandow Marcel , Sundt‐Hansen Line , Olsen Yngvar
Published: March 2004

A recent meta‐analysis indicates that trophic cascades (indirect effects of predators on plants via herbivores) are weak in marine plankton in striking contrast to freshwater plankton (Shurin et al. 2002, Ecol. Lett., 5, 785–791). Here we show that in a marine plankton community consisting of jellyfish, calanoid copepods and algae, jellyfish predation consistently reduced copepods but produced two distinct, opposite responses of algal biomass. Calanoid copepods act as a switch between alternative trophic cascades along food chains of different length and with counteracting effects on algal biomass. Copepods reduced large algae but simultaneously promoted small algae by feeding on ciliates. The net effect of jellyfish on total algal biomass was positive when large algae were initially abundant in the phytoplankton, negative when small algae were dominant, but zero when experiments were analysed in combination. In contrast to marine systems, major pathways of energy flow in Daphnia‐dominated freshwater systems are of similar chain length. Thus, differences in the length of alternative, parallel food chains may explain the apparent discrepancy in trophic cascade strength between freshwater and marine planktonic systems.
Contrary effects of jasmonate treatment of two closely related plant species on attraction of and oviposition by a specialist herbivore
Authors: Lu Yao‐bin , Liu Shu‐sheng , Liu Yin‐quan , Furlong Michael J. , Zalucki Myron P.
Published: March 2004

Elevated jasmonic acid (JA) concentrations in response to herbivory can induce wounded plants to produce defences against herbivores. In laboratory and field experiments we compared the effects of exogenous JA treatment to two closely related cabbage species on the host‐searching and oviposition preference of the diamondback moth (DBM), Plutella xylostella. JA‐treated Chinese cabbage (Brassica campestris) was less attractive than untreated Chinese cabbage to ovipositing DBM, while JA‐treatment of common cabbage (B. oleracea) made plants more attractive than untreated controls for oviposition by this insect. Similar effects were observed when plants of the two species were damaged by DBM larvae. In the absence of insect‐feeding, or JA application, Chinese cabbage is much more attractive to DBM than common cabbage. Inducible resistance therefore appears to occur in a more susceptible plant and induced susceptibility appears to occur in a more resistant plant, suggesting a possible balance mechanism between constitutive and inducible defences to a specialist herbivore.
Climate change, genotypic diversity and gene flow in reef‐building corals
Authors: Ayre David J. , Hughes Terence P.
Published: March 2004

In the ocean, large‐scale dispersal and replenishment by larvae is a key process underlying biological changes associated with global warming. On tropical reefs, coral bleaching, degradation of habitat and declining adult stocks are also likely to change contemporary patterns of dispersal and gene flow and may lead to range contractions or expansions. On the Great Barrier Reef, where adjacent reefs form a highly interconnected system, we use allozyme surveys of c. 3000 coral colonies to show that populations are genetically diverse, and rates of gene flow for a suite of five species range from modest to high among reefs up to 1200 km apart. In contrast, 700 km further south on Lord Howe Island, genetic diversity is markedly lower and populations are genetically isolated. The virtual absence of long‐distance dispersal of corals to geographically isolated, oceanic reefs renders them extremely vulnerable to global warming, even where local threats are minimal.
Global Crisis and Latin America
Authors: Robinson William I.
Published: March 2004

This essay examines Latin America's experience in the crisis and restructuring of world capitalism from the 1970s into the twenty‐first century, with particular emphasis on the neo‐liberal model, social conflicts and institutional quagmires that have engulfed the region, and the rise of a new resistance politics. The empirical and analytical sections look at: Latin America's changing profile in the global division of labour; the domination of speculative finance capital; the continued debt crisis, its social effects and political implications; capital–labour restructuring, the spread of informalisation and the new inequality; the passage from social explosions to institutional crises; the new popular electoral politics and the fragility of the neo‐liberal state. These issues are approached through the lens of global capitalism theory. This theory sees the turn‐of‐century global system as a new epoch in the history of world capitalism, emphasising new patterns of power and social polarisation worldwide and such concepts as a transnational accumulation, transnational capitalists and a transnational state. Finally, the essay argues that global capitalism faces a twin crisis in the early twenty‐first century, of overaccumulation and of legitimacy, and explores the prospects for social change in Latin America and worldwide.
The Messiness of Everyday Life: Exploring Key Themes in Latin American Citizenship Studies Introduction
Authors: Taylor Lucy , Wilson Fiona
Published: March 2004

This section seeks to provide a brief theoretical framework for the study of citizenship in Latin America by focusing on two characteristics which are of relevance to the essays collected here: belonging and political agency. It then goes on to discuss some key themes which emerge from a reading of the collected articles: methodology; civilisation and deviation; citizenship as the organisation of subordinate inclusion; popular ideas of citizenship as ‘fairness’; role of public performance in defining political relationships.
Struggles for Citizenship? Peasant Negotiation of Schooling in the Sierra Norte de Puebla, Mexico, 1921–1933
Authors: Rodrigo Ariadna Acevedo
Published: March 2004

This article identifies four different responses to educational policy in peasant villages. Acceptance, appropriation, resistance and opposition to schools are considered as forms of negotiating the educational contract. Peasants contributed to education through legal and customary practices. In return, they sought to influence the terms of schooling. However limited, such influence was possible because the Mexican state had scarce resources and depended on villagers’ support. Taking into account the difficulties of peasants’ subordinate position, their struggle over schooling is defined as a defence of autonomy rather than an exercise of citizenship.
Marching for Progress: Rituals of Citizenship, State and Belonging in a High Andes District
Authors: Stepputat Finn
Published: March 2004

This article explores processes of citizenship and state formation in the Central Peruvian Andes in the wake of the armed conflict through the lens of a public ritual, the celebration of a district anniversary. The celebration is a reservoir of practices from past forms of state formation and may be read as a claim for recognition as full‐blown members of the nation‐state. While practices of citizenship as rights are emerging, the celebration is permeated by the association between citizenship and civilization, with discipline playing a major role as an instrument of modernisation and progress.
Defining Accountability Up: the Global Economic Multilaterals
Authors: Kahler Miles
Published: March 2004

Critics of the global economic multilaterals (GEMs) – the International Monetary Fund, the World Bank, and the World Trade Organization – allege that these organizations fail the test of democratic accountability. Two distinct measures of democratic accountability have been applied to the GEMs. To the degree that these organizations display ‘accountability deficits’, those deficiencies are the result of choices by the most influential national governments. Three techniques have been deployed to enhance the accountability of the GEMs: transparency (more information for those outside the institution), competition (imitation of democratic accountability) and changes in rules of representation (accountability to stakeholders rather than shareholders). Each of these may impose costs, however, and may conflict with other valued aims of the organizations.
Disaggregated Sovereignty: Towards the Public Accountability of Global Government Networks
Authors: Slaughter Anne-Marie
Published: March 2004

Networks of government officials – police investigators, financial regulators, even judges and legislators – are a key feature of world order in the twenty-first century. Yet, these networks present significant accountability and legitimacy concerns. This article identifies and responds to the potential problems of government networks by suggesting means to increase their accountability and proposing norms to govern the relations of members of government networks with one another. Finally, the article develops the concept of disaggregated sovereignty, arguing that government networks have the capacity to enter into international regulatory regimes of various types and thereby are independently bound by the existing corpus of international law.
Global Governance, Participation and the Public Sphere
Authors: Nanz Patrizia , Steffek Jens
Published: March 2004

We argue that the democratization of global governance will ultimately depend upon the creation of an appropriate public sphere that connects decision-making processes with transnational constituency. The emergence of such a public sphere would require more transparency in international organizations as well as institutional settings in which policy-makers respond to stakeholders’ concerns. Organized civil society plays a key role by exposing global rule-making to public scrutiny and bringing citizens’ concerns onto the agenda. We illustrate the prospects and difficulties of building a transnational public sphere with the example of the WTO.
Is there a ‘Democratic Deficit’ in World Politics? A Framework for Analysis
Authors: Moravcsik Andrew
Published: March 2004

Many scholars, commentators and politicians assert that international organizations suffer from a severe ‘democratic deficit’. This article proposes a basic framework for evaluating this applied ethical critique of global governance. It rests on two criteria. The first, philosophical coherence, dictates consistent adherence to one or more conception of democratic legitimacy (libertarian, pluralist, social democratic or deliberative). The second, pragmatic appropriateness, requires that any philosophical standard be calibrated to reasonable expectations in the ‘second-best’ world constrained by transaction costs, commitment problems, and justice claims. The latter judgement is in large part empirical, for which existing constitutional practices in advanced industrial democracies provide the most reasonable baseline. By these two criteria – regardless of which specific conception of democracy is adopted as a starting point – the European Union appears to be democratically legitimate. This establishes a point of democratic legitimacy on the continuum of international institutions that could be analysed using this framework.
Immune responses in normal Indian langur monkeys (Presbytis entellus) – a primate model for visceral leishmaniasis
Authors: Misra Alka , Dube A. , Naik S.
Published: March 2004

Abstract:  The Indian langur monkey (Presbytis entellus) is an experimental host for a range of human diseases and for the assessment of vaccine candidate antigens to some common parasitic infections. This experimental host is particularly suitable for the follow‐up of immunological responses. To understand some of the mechanism that underlies the defense against experimental pathogens there is a need of the basic knowledge on antibody and cell mediated immune responses. In the present study 25 naïve monkeys were subjected to for assessment of their antibody responses to various human parasitic antigens as well as mitogen induced cellular responses. Only few monkeys were found to have low titer of antiparasitic antibodies. There was compressive dose dependent proliferative response of peripheral blood mononuclear cells. Unlike humans, the blastogenic as well as cytokine responses (IFN‐γ, IL‐2 and IL‐4) to Con A was considerably higher as compared to PHA. These findings are similar to what have been reported in other non‐human primates, confirming the appropriateness of Indian langurs for pre‐clinical trials.
Viral load in tissues during the early and chronic phase of non‐pathogenic SIVagm infection
Authors: Gueye A. , Diop O.M. , Ploquin M.J.Y. , Kornfeld C. , Faye A. , Cumont M.‐C. , Hurtrel B. , Barré‐Sinoussi F. , Müller‐Trutwin M.C.
Published: March 2004

Abstract:  African green monkeys (AGMs) persistently infected with SIVagm do not develop AIDS, although their plasma viremia levels can reach those reported for pathogenic HIV‐1 and SIVmac infections. In contrast, the viral burden in lymph nodes in SIVagm‐infected AGMs is generally lower in comparison with HIV/SIVmac pathogenic infections, at least during the chronic phase of SIVagm infection. We searched for the primary targets of viral replication, which might account for the high viremias in SIVagm‐infected AGMs. We evaluated for the first time during primary infection SIVagm dissemination in various lymphoid and non‐lymphoid tissues. Sixteen distinct organs at a time point corresponding to maximal virus production were analyzed for viral RNA and DNA load. At days 8 and 9 p.i., viral RNA could be detected in a wide range of tissues, such as jejunum, spleen, mesenteric lymph nodes, thymus and lung. Quantification of viral DNA and RNA as well as of productively infected cells revealed that viral replication during this early phase takes place mainly in secondary lymphoid organs and in the gut (5 × 104–5 × 108 RNA copies/106 cells). By 4 years p.i., RNA copy numbers were below detection level in thymus and lung. Secondary lymphoid organs displayed 6 × 102–2 × 106 RNA copies/106 cells, while some tissue fragments of ileum and jejunum still showed high viral loads (up to 109 copies/106 cells). Altogether, these results indicate a rapid dissemination of SIVagm into lymphoid tissues, including the small intestine. The latter, despite showing marked regional variations, most likely contributes significantly to the high levels of viremia observed during SIVagm infection.
Macaca fascicularis vs. Macaca nemestrina as a model for topical microbicide safety studies
Authors: Patton Dorothy L. , Sweeney Yvonne C. , Tsai Che‐Chung , Hillier Sharon L.
Published: March 2004

Abstract:  Preclinical studies of topical microbicide products, using appropriate animal models for assessing the safety of repeated use are essential. The pig‐tailed macaque (Macaca nemestrina) model has been used to assess the safety of vaginally and rectally applied topical microbicide products. The availability of sexually mature female pig‐tailed macaques has become extremely restricted. Currently, M. fascicularis is more readily available, and was therefore evaluated as an alternative model for topical microbicide pre‐clinical evaluation. Twenty sexually mature M. fascicularis were assessed for feasibility to mimic the established models. The rectal and cervicovaginal microenvironments of the M. fascicularis were determined to be similar to those of M. nemestrina and humans. The gross anatomy was significantly smaller than that of the pig‐tailed macaque, such that colposcopic examinations and multiple biopsies would not be possible. Thus, the M. fascicularis may not be useful for vaginally applied topical microbicide safety studies yet adequate for assessing safety of rectally applied topical microbicide products.
Intraperitoneal foreign body disease in a baboon (Papio hamadryas)
Authors: Mätz‐Rensing K. , Floto A. , Kaup F.‐J.
Published: March 2004

Abstract:  In a baboon group housed at the German Primate Center one animal became conspicuous with signs of massive abdominal pain in the upper gastric region. After clinical investigation an acute bloat‐syndrome was suspected as cause of the animals’ sickness. Symptomatic therapy was started but the animal died within a few hours. At necropsy a large piece of wood was found within the right kidney and liver. Prior to this, the foreign body passed the gastrointestinal tract and perforated the proximal colon. A clinico‐pathologic description of this uncommon spontaneous foreign body disease is given. The significance of injuries related to environmental enrichment is discussed.
Blue light inhibits melanin synthesis in B16 melanoma 4A5 cells and skin pigmentation induced by ultraviolet B in guinea‐pigs
Authors: Ohara M. , Kobayashi M. , Fujiwara H. , Kitajima S. , Mitsuoka C. , Watanabe H.
Published: March 2004

Background: Little has been known about the effects of visible light in mammalian cells. We recently found that blue light not only suppressed the growth of B16 melanoma cells in a time‐dependent manner but also inhibited metastasis of the B16 melanoma cells to the lung. These findings suggest that exposure to blue light modifies the functions of B16 melanoma cells. The present study investigated the effects of blue light on B16 melanoma 4A5 cells and Weiser–Maple guinea‐pigs to confirm the biological effect of blue light on melanin formation.

Method: The effect of red, green, and blue light on melanin synthesis in B16 melanoma 4A5 cells was measured. The back skin of brown Weiser–Maple guinea‐pigs was exposed to ultraviolet B (UVB; 588 mJ/cm2 (0.7 mW/cm2× 14 min) three times a week for 2 weeks to induce melanin deposition. Thirty minutes after each UVB exposure, blue light was applied for 30 min. Pigmentation of the exposed areas of skin was checked once a week, and photographs of the skin were taken by digital camera. Observation was continued for 18 days after the final UVB exposure.

Result: Melanin synthesis in B16 melanoma 4A5 cells was selectively suppressed by blue light, but blue light did not induce decolorization of previously produced melanin. In the back skin of brown guinea‐pigs, the brightness of the sites exposed to UVB began to decrease on the fifth day of the experiment, decreasing further from the 12th day to the 18th day after UVB exposure. The brightness of the sites exposed to UVB and blue light decreased in a manner similar during the UVB exposure, but remained relatively unchanged from the 12th day to the 30th day.

Conclusion: These results suggest that blue light suppresses melanin formation following repeated UVB exposure. Further investigation with various light such as blue light may lead to a new approach to the care of ultraviolet‐affected skin such as hyperpigmentation.
Whole‐body UVB (TL‐01) or UVA‐1 irradiation does not alter the levels of immunomodulatory cytokines in the serum of human volunteers
Authors: Mcloone P. , Man I. , Yule S. , Fluitman A. , Van loveren H. , Norval M. , Gibbs N.K.
Published: March 2004

Background/Purpose: Ultraviolet (UV) exposure of mammalian skin induces local and systemic immunosuppression. In mice it has been proposed that systemic immunosuppression is mediated by an UV‐induced cytokine cascade involving systemic interleukin (IL)‐4 and IL‐10 and a reduction in IL‐12 activity. To investigate whether there was a parallel mechanism in humans we examined the effect of whole‐body narrowband ultraviolet B (UVB) (311–313 nm; TL‐01) and ultraviolet A (UVA)‐1 (340–400 nm) on serum cytokine levels.

Methods/Results: In a first study, five male psoriatic subjects were whole‐body irradiated with three sessions of a standard UVB (TL‐01) phototherapy regimen previously shown to cause downregulation of natural killer cell activity and T helper 1 (Th1) and Th2 cytokine production by peripheral blood mononuclear cells. Enzyme‐linked immunoabsorbent assay (ELISA) of sera taken before and after the third session showed no effect of phototherapy on IL‐10 and tumour necrosis factor‐α (TNF‐α). In a second study, five healthy subjects received three whole‐body exposures of UVB (TL‐01) and five other healthy subjects received three exposures of UVA‐1 on alternate days (total 22 J/cm2). Blood samples were taken before the first irradiation and at 0, 4, 8, 12, 14, 24 and 48 h after the third irradiation. The sera were subsequently analysed for IL‐10, IL‐12, IL‐8, IL‐1β and TNF‐α, by ELISA. The levels of IL‐1β and TNF‐α were below detection limits (<5 pg/ml), while no significant change in the levels of IL‐10, IL‐12 or IL‐8 was detected as a result of either TL‐01 or UVA‐1.

Conclusion: It seems unlikely that a modulation in these circulating cytokines assessed in this study accounts for systemic UV‐induced immunosuppression in human subjects.
On Viscoelastic
Compliant Contact-Impact Models
Authors: Atanackovic T. M. , Spasic D. T.
Published: March 2004

We study dynamics of a mass, moving on a straight line, and impacting against the rigid wall through a deformable body, that we model as a straight rod of negligible mass. The chosen constitutive model of the viscoelastic body comprises fractional derivatives of stress and strain and the restrictions on the coefficients that follow from Clausius Duhem inequality. We show that the dynamics of the problem is governed by a single differential equation of real order. The obtained equation was solved numerically. The comparison is made to the solution obtained by the Laplace transform and Post’s inversion formula. The predictions of the model concerning the duration of the impact, maximal values of the impacting force and deformation as well as the restitution coefficient are determined for several values of system parameters.
On the Heavily Damped Response in Viscously Damped Dynamic Systems
Authors: Bulatovic R. M.
Published: March 2004

Free motions of viscously damped linear systems are studied. A heavily damped multi-degree-of-freedom system is defined as one for which all its eigenvalues are real, negative, and semi-simple. Several results are obtained which state conditions for the heavy damping of the system. The conditions are given directly in terms of the coefficients of system matrices and these conditions may yield design constraints in terms of the physical parameters of the system. An example illustrates the validity and usefulness of the presented results.
Mechanical Modeling of Fabrics in Bending
Authors: Lahey T. J. , Heppler G. R.
Published: March 2004

A fabric bending model that includes contributions from nonlinear elasticity, and viscous and Coulomb friction with hysteretic effects is presented. The model allows the recovery of the loading, unloading and hysteresis behaviors observed in the Kawabata evaluation system (KES) bending tests and provides the ability to simulate a continuum of property curves and to extrapolate to loading conditions not covered in the KES regimen. Model results are compared to experimental results. It is found that hysteretic behavior is observed due to friction between the yarns, and that nonlinear elastic behavior arises from jamming of the yarns and their subsequent compression.
Three-Dimensional Instabilities in Flow Past a Rotating Cylinder
Authors: Mittal S.
Published: March 2004

Flow past a spinning circular cylinder placed in a uniform stream is investigated via three-dimensional computations. A stabilized finite element method is utilized to solve the incompressible Navier-Stokes equations in the primitive variables formulation. The Reynolds number based on the cylinder diameter and freestream speed of the flow is 200. The nondimensional rotation rate, α, (ratio of the surface speed and freestream speed) is 5. It is found that although the two-dimensional flow for α=5 is stable, centrifugal instabilities exist along the entire span in a three-dimensional set-up. In addition, a “no-slip” side-wall can result in separation of flow near the cylinder ends. Both these effects lead to a loss in lift and increase in drag. The end conditions and aspect ratio of the cylinder play an important role in the flow past a spinning cylinder. It is shown that the Prandtl’s limit on the maximum lift generated by a spinning cylinder in a uniform flow does not hold.
Surface Instability of
a Semi-Infinite Elastic Body Under Surface van der Waals Forces
Authors: Ru C. Q.
Published: March 2004

It is shown that the surface of a semi-infinite linear elastic body attracted by a rigid flat through van der Waals-like forces is always unstable. The wavelength of the surface wrinkling is finite and decreases with the van der Waals interaction coefficient. In particular, this result implies that the deformation field of the semi-infinite linear elastic body attracted by a rigid flat cannot be determined uniquely.
Planar Accelerometer Configurations
Authors: Williams T. R. , Fyfe K. R.
Published: March 2004

Numerous accelerometer configurations have been proposed and implemented by previous researches to determine parameters of the motion of the body to which the accelerometers are attached. To date, there has been no study of the geometric requirements of such configurations. This paper presents the requirements for minimal configurations for the case of general planar motion.
Predicting Oscillatory Fluid-Elastic Instability of a Tongue-in-Groove Leakage Joint
Authors: Manko David J. , Sussman Myron M.
Published: March 2004

This paper describes the application of the small boundary displacement model (SBDM) of fluid-structure coupling for predicting oscillatory fluid-elastic instability of a tongue-in-groove leakage joint. This coupling model extends structural small displacement theory to fluid-structure interfaces, eliminating the need for temporally changing meshes when structural motion is small compared with joint dimensions. The SBDM algorithm accurately predicts the onset of oscillatory instability for a tongue-in-groove leakage joint when compared with experimental data. Even though the methodology is specifically applied to a tongue-in-groove joint, the approach is equally suitable for evaluating the fluid-elastic stability of leakage joints in general.
Crystallographic Comparison of Manganese- and Iron-Dependent Homoprotocatechuate 2,3-Dioxygenases
Authors: Vetting Matthew W. , Wackett Lawrence P. , Que Lawrence , Lipscomb John D. , Ohlendorf Douglas H.
Published: March 2004

The X-ray crystal structures of homoprotocatechuate 2,3-dioxygenases isolated fromArthrobacter globiformisandBrevibacterium fuscumhave been determined to high resolution. These enzymes exhibit 83% sequence identity, yet their activities depend on different transition metals, Mn2+and Fe2+, respectively. The structures allow the origins of metal ion selectivity and aspects of the molecular mechanism to be examined in detail. The homotetrameric enzymes belong to the type I family of extradiol dioxygenases (vicinal oxygen chelate superfamily); each monomer has four βαβββ modules forming two structurally homologous N-terminal and C-terminal barrel-shaped domains. The active-site metal is located in the C-terminal barrel and is ligated by two equatorial ligands, H214NE1and E267OE1; one axial ligand, H155NE1; and two to three water molecules. The first and second coordination spheres of these enzymes are virtually identical (root mean square difference over all atoms, 0.19 Å), suggesting that the metal selectivity must be due to changes at a significant distance from the metal and/or changes that occur during folding. The substrate (2,3-dihydroxyphenylacetate [HPCA]) chelates the metal asymmetrically at sitestransto the two imidazole ligands and interacts with a unique, mobile C-terminal loop. The loop closes over the bound substrate, presumably to seal the active site as the oxygen activation process commences. An “open” coordination sitetransto E267 is the likely binding site for O2. The geometry of the enzyme-substrate complexes suggests that if a transiently formed metal-superoxide complex attacks the substrate without dissociation from the metal, it must do so at the C-3 position. Second-sphere active-site residues that are positioned to interact with the HPCA and/or bound O2during catalysis are identified and discussed in the context of current mechanistic hypotheses.
Transcriptional Analysis of
spo0A
Overexpression in
Clostridium acetobutylicum
and Its Effect on the Cell's Response to Butanol Stress
Authors: Alsaker Keith V. , Spitzer Thomas R. , Papoutsakis Eleftherios T.
Published: March 2004

Spo0A is the regulator of stationary-phase events and is required for transcription of solvent formation genes in
Clostridium acetobutylicum
. In order to elucidate the role of
spo0A
in differentiation, we performed transcriptional analysis of 824(pMSPOA) (a
spo0A
-overexpressing
C. acetobutylicum
strain with enhanced sporulation) against a plasmid control strain. DNA microarray data were contrasted to data from a
spo0A
knockout strain (SKO1) that neither sporulates nor produces solvents. Transcripts of fatty acid metabolism genes, motility and chemotaxis genes, heat shock protein genes, and genes encoding the Fts family of cell division proteins were differentially expressed in the two strains, suggesting that these genes play roles in sporulation and the solvent stress response. 824(pMSPOA) alone showed significant downregulation of many glycolytic genes in stationary phase, which is consistent with metabolic flux analysis data. Surprisingly,
spo0A
overexpression resulted in only nominal transcriptional changes of regulatory genes (
abrB
and
sigF
) whose expression was significantly altered in SKO1. Overexpression of
spo0A
imparted increased tolerance and prolonged metabolism in response to butanol stress. While most of the differentially expressed genes appear to be part of a general stress response (similar to patterns in two plasmid control strains and a
groESL
-overexpressing strain), several genes were expressed at higher levels at early time points after butanol challenge only in 824(pMSPOA). Most of these genes were related to butyryl coenzyme A and butyrate formation and/or assimilation, but they also included the cell division gene
ftsX
, the gyrase subunit-encoding genes
gyrB
and
gyrA
, DNA synthesis and repair genes, and fatty acid synthesis genes, all of which might play a role in the immediate butanol stress response, and thus in enhanced butanol tolerance.
Sortase B, a New Class of Sortase inListeria monocytogenes
Authors: Bierne Hélène , Garandeau Caroline , Pucciarelli M. Graciela , Sabet Christophe , Newton Salete , Garcia-del Portillo Francisco , Cossart Pascale , Charbit Alain
Published: March 2004

Sortases are transamidases that covalently link proteins to the peptidoglycan of gram-positive bacteria. The genome of the pathogenic bacteriumListeria monocytogenesencodes two sortases genes,srtAandsrtB. ThesrtAgene product anchors internalin and some other LPXTG-containing proteins to the listerial surface. Here, we focus on the role of the second sortase, SrtB. Whereas SrtA acts on most of the proteins in the peptidoglycan fraction, SrtB appears to target minor amounts of surface polypeptides. We identified one of the SrtB-anchored proteins as the virulence factor SvpA, a surface-exposed protein which does not contain the LPXTG motif. Therefore, as inStaphylococcus aureus, the listerial SrtB represents a second class of sortase inL. monocytogenes, involved in the attachment of a subset of proteins to the cell wall, most likely by recognizing an NXZTN sorting motif. The ΔsrtBmutant strain does not have defects in bacterial entry, growth, or motility in tissue-cultured cells and does not show attenuated virulence in mice. SrtB-mediated anchoring could therefore be required to anchor surface proteins involved in the adaptation of this microorganism to different environmental conditions.
Contrasting Effects of σEon Compartmentalization of σFActivity during Sporulation ofBacillus subtilis
Authors: Hilbert David W. , Chary Vasant K. , Piggot Patrick J.
Published: March 2004

Spore formation byBacillus subtilisis a primitive form of development. In response to nutrient starvation and high cell density,B. subtilisdivides asymmetrically, resulting in two cells with different sizes and cell fates. Immediately after division, the transcription factor σFbecomes active in the smaller prespore, which is followed by the activation of σEin the larger mother cell. In this report, we examine the role of the mother cell-specific transcription factor σEin maintaining the compartmentalization of gene expression during development. We have studied a strain with a deletion of thespoIIIEgene, encoding a DNA translocase, that exhibits uncompartmentalized σFactivity. We have determined that the deletion ofspoIIIEalone does not substantially impact compartmentalization, but in thespoIIIEmutant, the expression of putative peptidoglycan hydrolases under the control of σEin the mother cell destroys the integrity of the septum. As a consequence, small proteins can cross the septum, thereby abolishing compartmentalization. In addition, we have found that in a mutant with partially impaired control of σF, the activation of σEin the mother cell is important to prevent the activation of σFin this compartment. Therefore, the activity of σEcan either maintain or abolish the compartmentalization of σF, depending upon the genetic makeup of the strain. We conclude that σEactivity must be carefully regulated in order to maintain compartmentalization of gene expression during development.
A Conjugation-Based System for Genetic Analysis of Group II Intron Splicing inLactococcus lactis
Authors: Klein Joanna R. , Chen Yuqing , Manias Dawn A. , Zhuo Jin , Zhou Liang , Peebles Craig L. , Dunny Gary M.
Published: March 2004

The conjugative element pRS01 fromLactococcus lactisencodes the putative relaxase protein LtrB. TheltrBgene is interrupted by the functional group II intron Ll.ltrB. Accurate splicing of the twoltrBexons is required for synthesis of the mRNA encoding the LtrB conjugative relaxase and subsequent plasmid transfer. A conjugation-based genetic assay was developed to identify Ll.ltrB mutations that affect splicing. In this assay a nonsplicing, transfer-defective pRS01 derivative (pM1014) and a shuttle vector carrying theltrBregion, including the Ll.ltrB intron (pCOM9), are used. pCOM9 provides splicing-dependent complementation of the transfer defect of pM1014. Site-directed mutations within Ll.ltrB, either in the catalytic RNA or in the intron-encoded protein geneltrA, were generated in the context of pCOM9. When these mutants were tested in the conjugation-based assay, significantly reduced mating was observed. Quantitative molecular analysis of in vivo splicing activity confirmed that the observed mating defects resulted from reduced splicing. Once the system was validated for the engineered mutants, random mutagenesis of the intron followed by genetic and molecular screening for splicing defects resulted in identification of point mutations that affect splicing.