[Staphylococcus aureus and its genotypes as a mastitis pathogen in dairy cattles - a review]

INTRODUCTION

In the last decade the knowledge on Staphylococcus aureus as the etiologic agent of chronic mastitis in dairy cattle has increased. Molecular biology and increasingly whole genome sequencing provide an advanced technology far beyond the classical, phenotypic bacteriology. Staphylococcus aureus has different characteristics, thus clinical and epidemiological properties are massively dependent on the genotypes. In Switzerland, Staphylococcus aureus genotype B (GTB) is a common genotype that causes infectious mastitis. Often, half and more cows of the herd are infected. Conversely, genotype C (GTC) and some of the other Staphylococcus aureus genotypes are classified less problematic because they affect individual cows and only one mammary gland quarter. Since Staphylococcus aureus GTB causes herd problems, the associated costs are high in the dairy industry. This applies in particular in the alpine region, because GTB-positive and -negative cows are not separated during milking and the infectious pathogen can spread rapidly. The pathogen is transferred by contaminated milking liners. Staphylococcus aureus GTB is highly associated with the mammary gland. In contrast, the skin and the udder are identified as the reservoir for Staphylococcus aureus GTC and the other genotypes. Staphylococcus aureus GTC is a classic infectious pathogen in wounds and occasionally in mammary glands.

Existence of two groups of Staphylococcus aureus strains isolated from bovine mastitis based on biofilm formation, intracellular survival, capsular profile and agr-typing

Staphylococcus (S.) aureus is recognised worldwide as an important pathogen causing contagious acute and chronic bovine mastitis. Chronic mastitis account for a significant part of all bovine cases and represent an important economic problem for dairy producers. Several properties (biofilm formation, intracellular survival, capsular expression and group agr) are thought to be associated with this chronic status. In a previous study, we found the existence of two groups of strains based on the association of these features. The aim of the present work was to confirm on a large international and non-related collection of strains the existence of these clusters and to associate them with case history records. In addition, the genomes of eight strains were sequenced to study the genomic differences between strains of each cluster. The results confirmed the existence of both groups based on capsular typing, intracellular survival and agr-typing: strains cap8-positive, belonging to agr group II, showing a low invasion rate and strains cap5-positive, belonging to agr group I, showing a high invasion rate. None of the two clusters were associated with the chronic status of the cow. When comparing the genomes of strains belonging to both clusters, the genes specific to the group "cap5-agrI" would suggest that these strains are better adapted to live in hostile environment. The existence of these two groups is highly important as they may represent two clusters that are adapted differently to the host and/or the surrounding environment.

Expression of Messenger RNA Coding for 5-HT Receptor, Alpha and Beta Adrenoreceptor (Subtypes) during Oestrus and Dioestrus in the Bovine Uterus

Serotoninergic and adrenergic receptors (5-HTR and AR) are involved in the regulation of uterine contractility. The objective of this study was to compare mRNA levels of 5-HTR(1A), 5-HTR(1B), 5-HTR(1D), 5-HTR(1F), 5-HTR(2A), 5-HTR(2B), 5-HTR(2C), 5-HTR(4) and alpha(1A), alpha(1B), alpha(1D), alpha(2AD), alpha(2B), alpha(2C), and beta(1), beta(2), beta(3)-AR in oestrus and dioestrus, and at three uterine locations (tip, middle and base) using quantitative real-time polymerase chain reaction. Uterine specimens consisting of endometrium and myometrium including vessels and serosa were collected from cows in oestrus (n = 10) and dioestrus (n = 15) respectively. Levels of 5-HTR and AR mRNA were expressed relative to the geometric mean of ribosomal RNA (18S), ubiquitin and glyceraldehyde phosphate dehydrogenase by the mean values of geNorm algorithm. 5-HTR(1A), 5-HTR(2C) and beta(3)-AR mRNA could not be detected in uterine tissues. The mRNA levels of 5-HTR(1F) and 5-HTR(2B) were lower (P < 0.05), but of 5-HTR(4) were higher (P < 0.05) in oestrus than in dioestrus. The mRNA levels of alpha(1A)-AR, alpha(2AD)-AR, alpha(2B)-AR were lower (P < 0.05), but of alpha(2C)-AR and beta(2)-AR were higher (P < 0.05) in oestrus than dioestrus. The mRNA levels of 5-HTR(1B) and 5-HTR(1D) (oestrus) and of alpha(2AD)-AR (dioestrus) differed among uterine locations (base > middle > tip; P < 0.05). The mRNA expression of 5-HTR and AR (subtypes) in bovine uterus was associated with cycle activity and varied according to uterine location. Additional studies on protein level will be carried out in order to elucidate the role of these receptor families on uterine contractility, which may then help to clarify clinical relevance.

P73 status in B-cell chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukemia is a heterogenous disease with disturbed apoptosis in which the precise molecular defects leading to this pathogenesis are still unclear. The p73 gene (a p53 homologue) encodes 2 proteins with opposing functions. TAp73 induces cell cycle arrest and apoptosis, whilst the oncogenic deltaNp73 inhibits both TAp73 and p53 induced apoptosis. Microsatellite analysis was performed to investigate the p73 gene locus in B-CLL. Moreover, we investigated the expression of the TAp73 and deltaNp73 variant by measuring the mRNA transcripts in 51 B-CLL patients by real-time RT-PCR. And in addition, protein expression was analyzed by Western blotting technique in 20 B-CLL patients. There was no evidence of clonal loss of heterozygosity at 1p36, the p73 gene locus in B-CLL patients. The real time RT-PCR analysis showed that the expression of both p73 gene variants was much higher in leukemic cells compared to controls. In 17/20 (85%) patients deltaNp73 and TAp73 protein were present. The observed increase of expression of the antiapoptotic deltaNp73 variant in neoplastic cells may lead to a functional p53 inactivation. This mechanism might be relevant in malignancies with an intact p53 gene but disturbed apoptosis mechanisms such as in B-CLL.

A high-resolution allelotype of B-cell chronic lymphocytic leukemia (B-CLL)

The most frequent chromosomal aberrations in B-cell chronic lymphocytic leukemia (B-CLL) are deletions on 13q, 11q, and 17p, and trisomy 12, all of which are of prognostic significance. Conventional cytogenetic analysis and fluorescence in situ hybridization (FISH) are used for their detection, but cytogenetic analysis is hampered by the low mitotic index of B-CLL cells, and FISH depends on accurate information about candidate regions. We used a set of 400 highly informative microsatellite markers covering all chromosomal arms (allelotyping) and automated polymerase chain reaction (PCR) protocols to screen 46 patients with typical B-CLL for chromosomal aberrations. For validation, we compared data with our conventional karyotype results and fine mapping with conventional single-site PCR. All clonal cytogenetic abnormalities potentially detectable by our microsatellite PCR (eg, del13q14 and trisomy 12) were picked up. Allelotyping revealed additional complex aberrations in patients with both normal and abnormal B-CLL karyotypes. Aberrations detectable in the samples with our microsatellite panel were found on almost all chromosomal arms. We detected new aberrant loci in typical B-CLL, such as allelic losses on 1q, 9q, and 22q in up to 25% of our patients, and allelic imbalances mirroring chromosomal duplications, amplifications, or aneuploidies on 2q, 10p, and 22q in up to 27% of our patients. We conclude that allelotyping with our battery of informative microsatellites is suitable for molecular screening of B-CLL. The technique is well suited for analyses in clinical trials, it provides a comprehensive view of genetic alterations, and it may identify new loci with candidate genes relevant in the molecular biology of B-CLL.

Normalized-constraint algorithm for minimizing inter-parameter crosstalk in DC optical tomography

In this report, we present a method for reducing the inter-coefficient crosstalk problem in optical tomography. The method described is an extension of a previously reported normalized difference method that evaluates relative detector values, and employs a weight matrix scaling technique together with a constrained CGD method for image reconstruction. Results from numerical and experimental studies using DC measurement data demonstrate that the approach can effectively isolate absorption and scattering heterogeneities, even for complex combinations of perturbations in optical properties. The significance of these results in light of recent theoretical findings is discussed.

Caspases: decoders of apoptotic signals during mammary involution. Caspase activation during involution

At weaning most of the alveolar epithelial cells in the mammary gland die by apoptosis and are removed by phagocytosis. Caspases are a family of aspartate specific cysteine proteases. Activation of caspases is generally thought to represent a major and irreversible event in the apoptotic process. We analyzed caspase expression and activation during mammary gland involution. A quantitative RT-PCR based approach revealed that levels of mRNA expression of several caspases are induced during involution. Using an antibody that specifically recognizes activated caspases we measured a transient induction of caspase activity in situ and found a maximal activation at days two and three of involution. These data were corroborated by monitoring caspase-3 like activity in mammary extracts with a synthetic DEVD-afc peptide as caspase-3 substrate. Using Fas-deficient mice we present evidence that the Fas signaling pathway is not essential for caspase activation and apoptosis during mammary gland involution. In summary, signaling pathways during involution seem to involve activation of caspases as intraepithelial triggers of mammary epithelial cell apoptosis.

Neurotensin receptor-1 mRNA analysis in normal pancreas and pancreatic disease

By autoradiography, neurotensin (NT) binding is specifically detectable in pancreatic cancer, but not in the normal pancreas, chronic pancreatitis (CP), or other pancreatic disorders. In the present study, we investigated whether this is due to NT receptor-1 (NTR-1) mRNA up-regulation and whether NTR-1 mRNA could also be used as a specific diagnostic marker and treatment target in pancreatic cancer. Fifteen normal pancreas tissue samples, 20 CP samples, and 30 pancreatic cancer samples were studied. Expression and localization of NTR-1 mRNA was investigated by Northern blot analysis and in situ hybridization. Furthermore, consecutive tissue sections were analyzed for NTR-1 mRNA expression and NT binding. By Northern blot analysis, NTR-1 mRNA expression was 4.4-fold (P < 0.01) and 3.0-fold (P < 0.01) higher in pancreatic cancer and CP tissue samples, respectively, compared with normal controls. There was no difference in NTR-1 mRNA levels between CP and cancer samples (P > 0.05). In pancreatic cancer, the NTR-1 mRNA levels were higher in advanced tumor stage (stages III and IV) than early tumor stage (stages I and II; P < 0.05), but no difference was found between well/moderately differentiated (grades 1 and 2) and poorly differentiated/undifferentiated cancers (grades 3 and 4; P > 0.05). By in situ hybridization, NTR-1 mRNA signals were weakly present in the cytoplasm of acinar and ductal cells of the normal pancreas. Moderate to intense NTR-1 mRNA signals were present in the cytoplasm of acinar cells dedifferentiating into tubular complexes and degenerating acinar cells of CP samples. In the cancer samples, NTR-1 mRNA was moderately to intensely expressed in the cytoplasm of cancer cells. When on consecutive tissue sections NTR-1 mRNA expression was compared with the presence of NTR-1, measured by receptor autoradiography, a correlation was found in carcinomas but not in CP samples, in which no receptors were detectable by autoradiography. The enhanced expression of NTR-1 mRNA in pancreatic cancer cells further suggests that neuroendocrine hormones might modulate pancreas cancer cell behavior. However, its relatively high levels in CP excludes NTR-1 mRNA as a specific parameter for pancreatic cancer and for the differentiation of pancreatic cancer from CP.

Connective tissue growth factor is a regulator for fibrosis in human chronic pancreatitis

OBJECTIVE

To evaluate the parameters that mediate fibrogenesis in chronic pancreatitis (CP).

BACKGROUND

Connective tissue growth factor (CTGF), which is regulated by transforming growth factor beta (TGF-beta), has recently been implicated in skin fibrosis and atherosclerosis. In the present study, the authors analyzed the concomitant presence of TGF-beta1 and its signaling receptors-TGF-beta receptor I, subtype ALK5 (TbetaR-I(ALK5)), and TGF-beta receptor II (TbetaR-II)-as well as CTGF and collagen type I in the pancreatic tissue of patients undergoing surgery for chronic pancreatitis.

PATIENTS AND METHODS

CP tissue samples were obtained from 40 patients (8 women, 32 men) undergoing pancreatic resection. Tissue samples of 25 previously healthy organ donors (12 women, 13 men) served as controls. The expression of TGF-beta1, TbetaR-I(ALK5), TbetaR-II, CTGF, and collagen type I was studied by Northern blot analysis. By in situ hybridization and immunohistochemistry, the respective mRNA moieties and proteins were localized in the tissue samples.

RESULTS

Northern blot analysis showed that CP tissue samples exhibited concomitant enhanced mRNA expression of TGF-beta1 (38-fold), TbetaR-II (5-fold), CTGF (25-fold), and collagen type I (24-fold) compared with normal controls. In addition, TbetaR-I(ALK5) mRNA was increased in 50% of CP tissue samples (1.8-fold). By in situ hybridization, TGF-beta1, TbetaR-I(ALK5), and TbetaR-II mRNA were often seen to be colocalized, especially in the ductal cells and in metaplastic areas where atrophic acinar cells appeared to dedifferentiate into ductal structures. In contrast, CTGF was located in degenerating acinar cells and principally in fibroblasts surrounding these areas. Moreover, CTGF mRNA expression levels correlated positively with the degree of fibrosis in CP tissues.

CONCLUSION

The concomitant overexpression of CTGF, collagen type I, TGF-beta1, and its signaling receptors in CP suggests that these proteins contribute to enhanced extracellular matrix synthesis and accumulation, resulting finally in the fibrogenesis observed in CP.

Transforming growth factor betas and their signaling receptors in human hepatocellular carcinoma

BACKGROUND

Transforming growth factor betas (TGF-betas) are multifunctional polypeptides that have been suggested to influence tumor growth. They mediate their functions via specific cell surface receptors (type I ALK5 and type II TGF-beta receptors). The aim of this study was to analyze the roles of the three TGF-betas and their signaling receptors in human hepatocellular carcinoma (HCC).

METHODS

HCC tissue samples were obtained from 18 patients undergoing partial liver resection. Normal liver tissues from 7 females and 3 males served as controls. The tissues for histological analysis were fixed in Bouin's solution and paraffin embedded. For RNA analysis, freshly obtained tissue samples were snap frozen in liquid nitrogen and stored at -80 degrees C until used. Northern blot analysis was used in normal liver and HCC to examine the expression of TGF-beta1, -beta2, -beta3 and their receptors: type I ALK5 (TbetaR-I ALK5), type II (TbetaR-II), and type III (TbetaR-III). Immunohistochemistry was performed to localize the corresponding proteins.

RESULTS

All three TGF-betas demonstrated a marked mRNA overexpression in HCC in comparison with normal controls, whereas the levels of all three TGF-beta receptors showed no significant changes. Intense TGF-beta1, TGF-beta2, and TGF-beta3 immunostaining was found in hepatocellular carcinoma cells and in the perineoplastic stroma with immunohistochemistry, whereas no or mild immunostaining was present in the normal liver. For TbetaR-I ALK5 and TbetaR-II, the immunostaining in both HCC and normal liver was mild to moderate, with a slightly higher intensity in the normal tissues.

CONCLUSION

The upregulation of TGF-betas in HCC suggests an important role for these isoforms in hepatic carcinogenesis and tumor progression. Moreover, the localization of the immunoreactivity in both malignant hepatocytes and stromal cells suggests that TGF-betas act via autocrine and paracrine pathways in this neoplasm.

Apoptosis inhibiting factor Bcl-xL might be the crucial member of the Bcl-2 gene family in colorectal cancer

Since the role of the Bcl-2 gene family has been only poorly investigated in colorectal cancer, we have examined the expression of the apoptosis blockers Bcl-xL and Bcl-2, as well as the proapoptotic factors Bax and Bak. Northern blot analysis and immunohistochemistry were performed on normal and cancerous colonic tissue from 12 patients. In colorectal cancer, Bcl-xL immunoreaction was stronger than in normal controls, and 83% of the cancers had increased Bcl-xL mRNA expression. The median densitometric Bcl-xL values were 3.4-fold higher in carcinomas (P<0.005). In contrast to the normal colon, colorectal carcinomas often lack any Bcl-2 immunostaining, and Bcl-2 mRNA was not detectable by Northern blots either. Bax was not obviously altered in colorectal cancer, either at the protein level or at the mRNA level compared to the normal control colon. Bak mRNA expression exhibited a wide variation in carcinomas, but was somewhat decreased in comparison to the controls. Of these members of the Bcl-2 gene family, Bcl-xL seems to play a major role in colorectal tumorigenesis and disease progression. An agonistic effect might have caused the tendency for reduced Bak expression. The Bcl-2/Bax regulation system of cell homeostasis seems to be of lesser importance.

Transforming growth factor-betas and their signaling receptors are coexpressed in Crohn's disease

OBJECTIVE

To evaluate mechanisms that contribute to tissue repair and tissue remodeling in Crohn's disease (CD).

SUMMARY BACKGROUND DATA

Transforming growth factor-betas (TGF-betas) are involved in different chronic inflammatory disorders. They function by binding to two receptors, type I (TbetaR-I) subtype ALK5 and type II (TbetaR-II), which are concomitantly required for signal transduction.

METHODS

Tissues were obtained from 18 patients with CD (10 female patients, 8 male patients, median age 38.7 years [range 16 to 58 years]) undergoing surgery because of CD-related complications. Tissue samples of 18 healthy organ donors (10 female subjects, 8 male subjects, median age 50.3 years [range 15 to 65 years]) served as controls. The expression and localization of TGF-beta1, TGF-beta2, TGF-beta3, TbetaR-IALK5, TbetaR-II, and TbetaR-III were studied by Northern blot analysis, in situ hybridization, and immunohistochemistry.

RESULTS

On Northern blot analysis, 94% of the CD samples exhibited enhanced TGF-beta1, TGF-beta3, and TbetaR-II mRNA expression compared with controls. TGF-beta2 was increased in 72%, TbetaR-IALK5 in 72%, and TbetaR-III in 82% of the patients with CD. On in situ hybridization and immunohistochemical analysis, TGF-beta1, TbetaR-IALK5, and TbetaR-II were seen to be colocalized in the lamina propria cells and in the lymphocytes closest to the luminal surface, but also in the remaining epithelial cells, and in fibroblasts of CD tissue samples.

CONCLUSIONS

The concomitant overexpression of TGF-betas and their signaling receptors in CD points to a potential role of these regulatory molecules in the pathophysiology of CD. Activation of TGF-beta-mediated pathways might promote the repair of mucosal injury by enhancing the process of reepithelization, but might also contribute to extracellular matrix generation and subsequently to intramural fibrosis and intestinal obstruction.

Apoptosis inhibiting factor Bcl-xL might be the crucial member of the Bcl-2 gene family in colorectal cancer

Since the role of the Bcl-2 gene family has been only poorly investigated in colorectal cancer, we have examined the expression of the apoptosis blockers Bcl-xL and Bcl-2, as well as the proapoptotic factors Bax and Bak. Northern blot analysis and immunohistochemistry were performed on normal and cancerous colonic tissue from 12 patients. In colorectal cancer, Bcl-xL immunoreaction was stronger than in normal controls, and 83% of the cancers had increased Bcl-xL mRNA expression. The median densitometric Bcl-xL values were 3.4-fold higher in carcinomas (P<0.005). In contrast to the normal colon, colorectal carcinomas often lack any Bcl-2 immunostaining, and Bcl-2 mRNA was not detectable by Northern blots either. Bax was not obviously altered in colorectal cancer, either at the protein level or at the mRNA level compared to the normal control colon. Bak mRNA expression exhibited a wide variation in carcinomas, but was somewhat decreased in comparison to the controls. Of these members of the Bcl-2 gene family, Bcl-xL seems to play a major role in colorectal tumorigenesis and disease progression. An agonistic effect might have caused the tendency for reduced Bak expression. The Bcl-2/Bax regulation system of cell homeostasis seems to be of lesser importance.

The plasminogen activator/plasmin system is up-regulated after acute necrotizing pancreatitis in human beings

BACKGROUND

Proteolysis and formation of new extracellular matrix components are important mechanisms in tissue remodeling and repair. In this study we analyzed the expression and distribution of the urokinase plasminogen activator (uPA), its membrane receptor (urokinase plasminogen activator receptor [uPAR]), and its inhibitor (plasminogen activator inhibitor-1 [PAI-1]) in acute necrotizing pancreatitis in human beings. In addition, we studied the concomitant expression of transforming growth factor-beta-1 (TGF-beta 1), which is activated by uPA from its precursor and is a potent regulator and stimulator of formation of extracellular matrix.

METHODS

With immunohistochemistry and Northern blot analysis, the expression and cellular distribution of uPA, uPAR, PAI-1, and TGF-beta 1 were determined in 12 normal pancreata obtained from organ donors and 12 pancreatic tissues obtained from patients undergoing operation because of complications of acute necrotizing pancreatitis.

RESULTS

Northern blot analysis showed enhanced expression of uPA, uPAR, and PAI-1 in eight of 12, seven of 12, and nine of 12 necrotizing pancreatitis samples, respectively, compared with normal control samples. In addition, increased TGF-beta 1 mRNA expression was present in eight of 12 necrotizing pancreatitis samples. In contrast, amylase mRNA expression was markedly decreased in the samples of acute necrotizing pancreatitis. Immunohistochemistry revealed elevated uPA, uPAR, and PAI-1 immunoreactivity in the remaining acinar and ductal cells adjacent to the necrotic tissue areas. In contrast, acinar and ductal cells that were located farther from pancreatic necrosis exhibited less uPA and uPAR immunoreactivity. A similar staining pattern in samples of necrotizing pancreatitis was found for TGF-beta 1.

CONCLUSIONS

Up-regulation of uPA and uPAR, which activate proteolysis, might create a milieu that enhances lysis and removal of pancreatic necrosis. The increase in TGF-beta 1 might result from the enhanced catalytic conversion of its precursors by uPA, which subsequently might stimulate formation of extracellular matrix, formation of granulation tissue, and fibrosis.

Genetic aspects of idiopathic epilepsy in Labrador retrievers

A study was undertaken to define the mode of inheritance of idiopathic epilepsy in Labrador retrievers in Switzerland. Seven hundred and ninety-two pedigree certificates from a population of healthy and epileptic dogs from 11 generations were evaluated. Forty-four different families (giving a total of 55 epileptic dogs) were included. Most patients showed generalised grand mal seizures and the onset was within one to three years in 41 per cent. Males were no more affected than females and the gender ratio between epileptic and control animals was not significantly different (P > 0.05). Additionally, there was no difference in average total inbreeding coefficient between both sexes, or with respect to age of onset of seizures. The increased manifestation of seizures in some subpopulations and the repeated occurrence in different families of the same sires suggested that there was a genetic basis for the condition in the breed. Results of pedigree analyses and from use of the binomial test support the hypothesis of a polygenic, recessive mode of inheritance. However, only an objective test-mating programme is likely to define the exact mode of inheritance.

Over-expression of ICAM-1, VCAM-1 and ELAM-1 might influence tumor progression in colorectal cancer

Adhesion molecules might play a role in tumor progression. We investigated expression of the adhesion molecules ICAM-1, VCAM-1 and ELAM-1 in 24 primary colorectal carcinomas using immuno-histochemistry and Northern blot analysis. Normal colonic tissue from the same patients served as controls. ICAM-1 immunostaining was restricted to the intercellular matrix and vascular endothelial cells. The vast majority of normal tissue samples revealed only faint ICAM-1 immunoreactivity. However, moderate to strong immunostaining was found in 86% of cancerous sections. The ICAM-1 immunoreaction was more intense in well-differentiated carcinomas as well as in the adenomatous parts and transition zones of cancers. Similarly, the cancers exhibited markedly enhanced VCAM-1 and ELAM-1 immunostaining in the endothelial cells of small blood vessels. The intense vascular immunostaining by ICAM-1 and VCAM-1 was associated with a strong presence of CD3-positive T lymphocytes, whereas ELAM-1 immunoreactivity did not correlate with round cell infiltration. On Northern blot analysis, ICAM-1, VCAM-1 and ELAM-1 mRNA levels were increased in 67%, 57% and 63% of carcinomas, respectively, in comparison with normal tissue samples. Densitometric analysis of Northern blots revealed an increase in ICAM-1 by 2.1-fold, an increase in VCAM-1 by 3.4-fold and an increase in ELAM-1 by 2.2-fold in cancerous tissues compared to normal controls. Over-expression of ICAM-I might prevent cell-cell disruption and, hence, tumor dissemination. Furthermore, over-expression of ICAM-1 and VCAM-1, but not ELAM-1, might favor host anti-tumor defense by trafficking of lymphocytes.

Over-expression of ICAM-1, VCAM-1 and ELAM-1 might influence tumor progression in colorectal cancer

Adhesion molecules might play a role in tumor progression. We investigated expression of the adhesion molecules ICAM-1, VCAM-1 and ELAM-1 in 24 primary colorectal carcinomas using immuno-histochemistry and Northern blot analysis. Normal colonic tissue from the same patients served as controls. ICAM-1 immunostaining was restricted to the intercellular matrix and vascular endothelial cells. The vast majority of normal tissue samples revealed only faint ICAM-1 immunoreactivity. However, moderate to strong immunostaining was found in 86% of cancerous sections. The ICAM-1 immunoreaction was more intense in well-differentiated carcinomas as well as in the adenomatous parts and transition zones of cancers. Similarly, the cancers exhibited markedly enhanced VCAM-1 and ELAM-1 immunostaining in the endothelial cells of small blood vessels. The intense vascular immunostaining by ICAM-1 and VCAM-1 was associated with a strong presence of CD3-positive T lymphocytes, whereas ELAM-1 immunoreactivity did not correlate with round cell infiltration. On Northern blot analysis, ICAM-1, VCAM-1 and ELAM-1 mRNA levels were increased in 67%, 57% and 63% of carcinomas, respectively, in comparison with normal tissue samples. Densitometric analysis of Northern blots revealed an increase in ICAM-1 by 2.1-fold, an increase in VCAM-1 by 3.4-fold and an increase in ELAM-1 by 2.2-fold in cancerous tissues compared to normal controls. Over-expression of ICAM-I might prevent cell-cell disruption and, hence, tumor dissemination. Furthermore, over-expression of ICAM-1 and VCAM-1, but not ELAM-1, might favor host anti-tumor defense by trafficking of lymphocytes.

Phospholipase A2 isoforms are altered in chronic pancreatitis

OBJECTIVE

To determine if phospholipase A2 (PLA2) type II and type IV mRNA expression and protein are altered in chronic pancreatitis.

SUMMARY BACKGROUND DATA

PLA2s have an important regulatory function in several signaling pathways, especially in inflammation. In this study, we examined the expression of three PLA2 isoforms (type I, type II, and type IV) in chronic pancreatitis.

METHODS

The distribution of PLA2 was studied in 15 pancreas samples obtained from patients with chronic pancreatitis using immunohistochemical, Northern blot, and in situ hybridization techniques. Normal pancreas obtained from healthy organ donors served as control.

RESULTS

Northern blot analysis revealed enhanced mRNA levels of PLA2 type II (5.7-fold) and type IV (5.1-fold) in chronic pancreatitis (p < 0.01) versus normal pancreas. In normal pancreas, intense PLA2 type I immunostaining was present in acinar cells, whereas PLA2 type II immunostaining was visible only in some acinar cells. In chronic pancreatitis, PLA2 type II immunostaining was present more frequently and with higher intensity in acinar cells. Furthermore, PLA2 type II immunoreactivity was more abundant in metaplastic ductal cells in the chronic pancreatitis samples. By in situ hybridization, areas with ductal metaplasia in chronic pancreatitis exhibited intense PLA2 type IV mRNA signals. All chronic pancreatitis tissues with concomitantly increased mRNA expression for PLA2 type II and type IV exhibited a higher degree of degeneration, ductal metaplasia, and fibrosis.

CONCLUSIONS

Upregulation of PLA2 types II and IV in areas with more histologic damage suggests that these PLA2 isoforms might contribute to the morphologic changes that occur in chronic pancreatitis.

Enhanced urokinase plasminogen activation in chronic pancreatitis suggests a role in its pathogenesis

BACKGROUND & AIMS

Urokinase plasminogen activator (uPA) regulates plasmin generation from plasminogen. The aim of this study was to analyze the role of the plasminogen activator/plasmin system in chronic pancreatitis (CP).

METHODS

Using Northern blot analysis, in situ hybridization, and immunohistochemistry, the expression of uPA, its receptor (uPAR), plasminogen activator inhibitor 1 (PAI-1), and transforming growth factor beta 1 (TGF-beta 1) was studied in 14 patients undergoing pancreatic resection for CP. Normal control pancreatic tissue was obtained through an organ donor program.

RESULTS

Eight of 14 CP samples showed concomitant increased expression (P < 0.001) of uPA (5.2-fold), uPAR (5.9-fold), and TGF-beta 1 (8.8-fold) messenger RNA (mRNA) compared with normal controls. PAI-1 mRNA expression was increased (6.5-fold; P < 0.001) in all CP samples. By in situ hybridization, moderate to strong mRNA staining of all four factors was present in acinar cells, some ductal cells, and areas with ductal metaplasia in CP samples. A similar staining pattern was found by immunohistochemistry. Intense mRNA and immunostaining for all of these factors in CP samples was associated with a higher degree of pancreatic damage.

CONCLUSIONS

uPA and its receptor may contribute to the lytic damage observed in CP by plasmin generation. Similarly, increased amounts of plasmin may activate latent TGF-beta, thereby leading to the accumulation of fibrotic tissue.

Anti-beta-receptor antibodies in familial cardiomyopathy: correlation with HLA-DR and HLA-DQ gene polymorphisms

The presence of beta-receptor autoantibodies and their relationship to restriction fragment length polymorphisms of the human leukocyte antigen (HLA) class II genes were studied in 42 affected and unaffected members of a family with a heritable disorder of the conduction system and cardiac muscle. Antibodies were detected in 34% of all members (59% of affected and 22% of unaffected; p < 0.01). Significant differences between affected and unaffected individuals and between anti-beta-receptor antibody positive and negative individuals were noted in the prevalence of polymorphisms obtained with Taq I for the HLA-DR beta and HLA-DQ alpha genes. In affected individuals, there was a strong positive correlation between these polymorphisms and the presence of anti-beta-receptor antibodies. These results suggest that autoimmune mechanisms under the control of the class II genes play an important role in the pathogenesis of familial cardiomyopathy.

T-cell receptor gene polymorphisms in familial cardiomyopathy: correlation with anti-beta-receptor autoantibodies

Cardiac autoantibodies have been detected in a significant proportion of patients with dilated cardiomyopathy, but their relation to the pathogenesis of the disease remains unknown. This issue was examined in 41 members of an Ohio family with a heritable disorder of the cardiac conduction system and the myocardium. In 41.5% of all members studied, serum anti-beta-receptor antibodies were identified by a combination of techniques: ligand binding inhibition assay, enzyme-linked immunoassay of a beta 1-receptor peptide, and adenylate cyclase inhibition. The prevalence of autoantibodies was significantly higher (p < 0.01) in the affected (64.7%) than in the unaffected (25.0%) members. A 10.0 kb restriction fragment length polymorphism of the C beta region of the T-cell receptor gene was also overrepresented in affected males (60% versus 30% unaffected males, p < 0.01). In males, the presence of anti-beta-receptor antibodies was linked to the 10.0 kb C beta polymorphism. In affected males, a BlgII C alpha 2.14 kb polymorphism was also more frequent (62% versus 32% in unaffected, p < 0.01) and was linked to the presence of anti-beta-receptor antibodies. The distribution of haplotypes defined by V beta 8, C alpha, and C beta probes was significantly different between affected and unaffected (p < 0.04) and between antibody-positive and antibody-negative individuals. Since the major function of the T-cell receptor is the recognition of processed autoantigens, these results provide additional support for the role of autoimmunity in dilated cardiomyopathy.

Metabolic interactions of ciprofloxacin

The mechanism and clinical relevance of the inhibitory effect of ciprofloxacin on the metabolism of selected drugs were studied in patients with bacterial infections. In study A, antipyrine tests were carried out in two groups of patients taking 1000 mg (group 1) and 250 mg (group 2) of oral ciprofloxacin for 7-10 days. Antipyrine was given intravenously in a dose of 15 mg/kg body weight before and after ciprofloxacin treatment. Blood samples were taken at 0, 2, 4, 6, and 10 hr after dosing. In group 1, ciprofloxacin administration resulted in a significant decrease in antipyrine elimination (t1/2, 9.45 +/- 3.74 vs. 14.92 +/- 3.32 hr). The average decrease in antipyrine clearance was 35% (0.85 +/- 0.45 vs. 0.52 +/- 0.24 ml/min/kg). In group 2, the change in antipyrine kinetics was less pronounced (t1/2, 9.79 +/- 3.06 vs. 11.22 +/- 2.64 hr). Antipyrine clearance was decreased by only 10% (0.77 +/- 0.13 vs. 0.70 +/- 0.14 ml/min/kg). These results support the hypothesis that ciprofloxacin inhibits the oxidative metabolism in the liver. However, according to the analysis of variance data, the inhibitory effect is dose dependent. At a dose of 1000 mg daily, ciprofloxacin may induce drug interactions whereas, at a dose of 250 mg daily, the likelihood of drug interactions is improbable. In study B, cimetidine (1000 mg orally daily) and ciprofloxacin (500 mg twice daily) were administered simultaneously to eight patients. Blood samples for the determination of ciprofloxacin concentrations were taken at 0, 1, 2, 4, 6, and 12 hr after dosing on the first and seventh day of drug administration.(ABSTRACT TRUNCATED AT 250 WORDS)

[Antimicrobial chemotherapy--its clinico-pharmacologic significance]

Remembering of Markusovszky, the outstanding Hungarian physician of the last century, author quotes Markusovszky's comments on perspectives of infectious diseases, then outlines the development of antibacterial chemotherapy. Some problems are discussed concerning the clinical pharmacology of the aminoglycoside and cephalosporin antibiotics and those of the new quinolones as well. Some results of author's and her coworker's researches are presented.

The effect of ciprofloxacin on antipyrine metabolism

The effect of multiple-dose ciprofloxacin on antipyrine metabolism was studied in patients suffering from bacterial infections. The patients were given antipyrine 15 mg/kg intravenously before and after ciprofloxacin treatment. The dosage of ciprofloxacin was 500 mg bd by mouth for 8-10 days. Blood samples were taken at 0, 2, 4, 6, 10 h. Antipyrine total clearance was significantly decreased after ciprofloxacin treatment (0.85 +/- 0.45 vs. 0.52 +/- 0.24 ml/min/kg): elimination rate constants for antipyrine were decreased in all patients after ciprofloxacin, whereas no change in volume of distribution was observed. The average half-life of antipyrine was increased from 9.45 +/- 3.74 h to 14.92 +/- 3.32 h. In two males with advanced chronic hepatic failure the antipyrine half-lives were extremely prolonged. Our results support the hypothesis that ciprofloxacin inhibits intrinsic hepatic drug-metabolizing capacity and may be a source of clinically important drug interactions, particularly in patients with liver disease.

Pharmacokinetics of cefotaxime and desacetylcefotaxime in elderly patients

This study was undertaken to determine the effect of age on the pharmacokinetics of cefotaxime and desacetylcefotaxime after intravenous administration of 1 g cefotaxime. 30 elderly patients suffering from acute infection were enrolled in the study. They were divided into 3 subgroups (group I aged 60 to 70 years, group II aged 71 to 80 years, group III aged over 80 years) with 5 men and 5 women in each. The elimination of cefotaxime in patients aged between 60 and 80 years was slightly slower than that in young people: elimination half-lives (in men and women, respectively) in group I were 1.2 and 1.58 hours, in group II, 1.45 and 1.57 hours and in group III, 2.56 and 2.59 hours. The change in elimination of desacetylcefotaxime was similar to that of cefotaxime, but less marked. The slower elimination of cefotaxime in patients over 80 years of age may allow reduction in the dose without jeopardizing the efficacy of therapy, whereas in patients under 80 years of age the normal dosage is required.

Microbiologic and clinical studies with cefuroxime

The microbiologic and therapeutic efficacy of cefuroxime, a lactamase-stable cephalosporin, was studied. Of the 2532 bacterial isolates of clinical origin, 80-95% of the E. coli, indole-negative Proteus, Klebsiella-enterobacter, Staphylococcus aureus, and 72-74% of indole-positive Proteus and Streptococcus B haemolyticus strains were found susceptible to cefuroxime by the disc method. Forty-three bacterial infections of 36 patients were treated; most of them were critically or seriously ill at the start of treatment. Half of the patients had failed to respond to previous antibacterial therapy. Cefuroxime was administered in doses of 750 and 1500 mg, three times daily, for an average of 11 days (6-37 days). Ten patients received an aminoglycoside in addition to cefuroxime. Forty-one infections of 34 patients were cured, one relapsed, and one did not respond. The pathogen was identified in 36 infections; in 34 it was eradicated. Cefuroxime was well tolerated by all patients including one with penicillin allergy. No side effects occurred except local pain at the site of i.m. injections in two cases. It is concluded that cefuroxime has a high efficacy against resistant strains and an outstanding value in severe bacterial infections.

Age-associated pharmacokinetic changes of metronidazole

Serum concentration and urinary excretion of metronidazole were determined after p.o. administration of 500 mg to 15 young (20-25 years old) and 20 elderly (over 70) subjects. Serum levels were consistently higher and the AUCs were almost doubled in the aged group. One of the effects underlying the decrease in total clearance is the diminished renal excretion; however, the role of the reduction of distribution volume seems to be more important. Red cell binding of metronidazole significantly decreased in the aged group; this may also contribute to the reduction of distribution volume. Reduction of the standard dose of metronidazole by 30-40% is recommended in elderly patients.

Pharmacokinetic and clinical studies with carfecillin

The pharmacokinetics of carfecillin (Carbenicillin-phenyl-ester) were studied in 10 healthy subjects, in 5 patients with hepatic cirrhosis and in 5 cases of renal insufficiency. In healthy subjects maximal carbenicillin serum levels attained by therapeutic doses were about 20 microgram/ml; concentrations in the urine surpassed 1000 mu/ml. The phenol moiety was detectable as free phenol in sera (less than 1 microgram/ml) and urine (less than 3 microgram/ml), but its major part was transformed to glucuronide and sulphate conjugates. Pharmacokinetics were not altered significantly by hepatic lesion. In renal insufficiency, serum levels of both carbenicillin and conjugated phenol were higher and their decrease delayed, while urine concentration was low. Carfecillin treatment was successful in 20 out of 30 patients with UTI.