Separation of milk fat globules via microfiltration: Effect of diafiltration media and opportunities for stream valorization.

Milk fat globule membranes (MFGM) sourced in buttermilk have gained recent interest given their nutritional value and functional properties. However, production of isolated MFGM has been challenging given their size similarity with casein micelles, which limits attempts toward fractionation by size exclusion techniques. Therefore, the hypothesis underpinning this study is that the removal of proteins from cream before butter-making facilitates MFGM isolation. As such, milk fat globules were separated from raw whole milk via microfiltration (1.4-µm pore diameter and 0.005-m2 filtration surface area) by using 3 diafiltration media; namely, skim milk ultrafiltration permeate, saline, and water. Their effects on the stability of the milk fat globules and protein permeation was elucidated. Whereas a substantial reduction in protein concentration was achieved with all diafiltration media (~90% reduction), water and saline produced negligible membrane fouling with better filtration performance. Moreover, diafiltration with skim milk ultrafiltration permeate exhibited reduced permeate flux. Colloidal stability of the resultant milk decreased with all diafiltration solutions due to changing composition and reduced apparent viscosity. Overall, microfiltration was found to be an efficient method for separation of milk fat globules from whole milk, leading to increased MFGM fragment concentration in buttermilk dry matter, thus making it more suitable for industrial utilization.

Immunohistochemical study of matrix metalloproteinase 9 and tissue inhibitor of matrix metalloproteinase 1 in benign and malignant breast tissue--strong expression in intraductal carcinomas of the breast.

OBJECTIVE: Matrix metalloproteinases (MMPs) are involved in carcinogenesis due to their tissue remodeling capability, and there is convincing evidence linking gelatinase B (MMP-9) with malignant cell invasion. Tissue inhibitor 1 of MMP (TIMP-1) is a strong inhibitor of MMP-9 but has also tumor-enhancing effects. Only few data exist on MMP-9 or TIMP-1 expression in tissue samples of different breast histology. METHODS: MMP-9 and TIMP-1 immunoreactivity was examined in a wide range of breast tissue samples differing in histology from usual ductal hyperplasia (UDH) to fully developed ductal breast carcinoma. Immunohistochemical expression of MMP-9 was studied in 178 samples: 31 UDH samples, 29 atypical ductal hyperplasia (ADH) samples, 28 ductal carcinoma in situ (DCIS) samples and 90 ductal invasive carcinoma samples (30 samples of malignancy grades I, II and III, respectively). TIMP-1 expression was also analyzed in 178 breast tissue samples: 41 UDH, 21 ADH and 34 DCIS lesions, and 82 invasive ductal breast carcinomas (25 in grade I, 30 in grade II and 27 in grade III). RESULTS: A significantly distinctive pattern of MMP-9 protein expression was shown in DCIS samples, where 85.7% of the cases showed moderate or strong positivity and negative staining was rare (p = 0.021). Negative or weakly positive MMP-9 staining was the most prominent finding in UDH (71%), ADH (69%) as well as in invasive carcinoma samples (64.4%). Various degrees of TIMP-1 expression were seen in 86.5% of all cases. DCIS and invasive carcinoma samples revealed similar immunostaining: at least some positivity was seen in 91.1% of the DCIS samples and 91.5% of infiltrative carcinomas. Thus, TIMP-1 negativity (22.2%) was significantly associated with hyperplastic lesions (p = 0.026). CONCLUSIONS: These results suggest that MMP-9 and TIMP-1 overexpression are early markers of breast carcinogenesis preceding tumor invasion. Apparently, DCIS carries the risk to evolve into a malignant phenotype according to these markers. The clinical importance of these findings is discussed.

A mutant TP53 gene status is associated with a poor prognosis and anthracycline-resistance in breast cancer patients.

This study evaluates the prognostic and predictive relevance of a mutated p53 in a series of 254 samples from primary breast cancer patients. C-erbB-2 analysis was defined in a limited subpopulation of 79 patients. p53 and c-erbB-2 status was analysed by immunohistochemical staining of the tumour samples. Positive p53 immunostaining was present in 86 cases (34%) and correlated with a high malignant grade, negative progesterone receptor status and ductal histology of tumour. C-erbB-2 positivity was seen in 38 samples (48%). Within an average follow-up time of 74 months, 121 patients developed recurrent or metastatic disease. Patients with mutated p53 showed a statistically significant shorter overall survival and disease-free survival in both univariate and multivariate analyses. The worst clinical outcome was seen in patients who were both p53- and c-erbB-2-positive. The response rate to anthracycline-based chemotherapy in metastatic disease was low in the p53-positive cases. Our results help to clarify the independent prognostic role of a mutated p53 status in breast cancer patients, indicating that this gene might be predictive of anthracycline resistance. Patients with a mutant p53 status and overexpressing c-erbB-2 should be regarded as high-risk cases.

Aminoterminal propeptide of the alpha1-homotrimer variant of human type I procollagen (hotPINP) in malignant pleural effusion.

The aminoterminal propeptide (hotPINP) of type I homotrimer, a putative malignancy-associated type I collagen variant, was purified for the first time and a method was established for its detection in pleural fluid. Samples of 58 patients, with malignant or benign disease, were studied with specific immunoassays for the two propeptides of type-I procollagen (PICP and PINP) and with HPLC-DEAE chromatography to separate the two PINP variants. HotPINP was present in 64% of both benign and malignant pleural effusion fluids, with the exception of malignant mesotheliomas, none of which showed the presence of hotPINP. Also the PICP to PINP ratios were lower than normal in both benign and malignant samples (altogether in 69% of samples), although this deviation was greater in malignancy. These two phenomena were independent of each other. As synthesis of the alpha1-homotrimer-variant of type-I collagen seems to be relatively common during the formation of pleural effusion, it may be generally related to a fibroproliferative reaction in the pleural wall.

Postoperative PINP in serum reflects metastatic potential and poor survival in node-positive breast cancer.

The aim of this work was to evaluate the postoperative serum markers of type I collagen synthesis (PINP,PICP) and degradation (ICTP) and their possible potential for predicting the spread of disease and survival. 373 node-positive breast cancer patients were enrolled. 120 patients (32%) developed recurrent disease in the follow-up. The mean time to recurrence was 17 months and the mean follow-up time was 45 months. The mean level of PINP was significantly elevated in the patients who developed metastatic disease in the follow-up as compared with those without metastases. PINP was statistically significantly higher in all the patients who developed bone metastases than in those without metastases. When patients with only bone metastases or patients with bone and soft tissue and/or visceral metastases and patients with only visceral or soft tissue metastases were compared with those not exhibiting metastases, PINP was significantly higher in the group with recurrence in the bone, but there were no significant differences in serum PINP, PICP or ICTP values between the patients with only bone metastases and those who developed soft or visceral metastases during the follow-up. Postoperative high PINP was also a factor for poorer survivaL Tumor size, malignancy grade and progesterone receptors were shown in multivariate analysis to be predictors of recurrence and tumor size and PINP and progesterone receptors to be predictors of survivaL

A phenotypic change of small intestinal epithelium to colonocytes in small intestinal adenomas and adenocarcinomas.

OBJECTIVE: Using a novel monoclonal antibody (mAb Das-1) that specifically reacts with colon epithelium, we examined if there is a phenotypic change of small intestinal enterocytes toward colonocytes in small intestinal neoplastic tissue. METHODS: Tissue sections of the small intestine consisting of adenomas (n = 20, five with histories of familial polyposis), adenocarcinomas (eight primary and one metastatic from colon). carcinoids (n = 2), and hyperplastic polyps (n = 3) were examined by a sensitive immunoperoxidase assay using mAb Das-1 (IgM isotype). Normal jejunal (n = 10) and colonic (n = 10) biopsy specimens were also included as additional controls. RESULTS: mAb Das-1 reacted with normal colonic epithelium but not with jejunal mucosa. However, mAb Das-1 reacted strongly with each of the five adenomas (100%) from patients with histories of familial polyposis, but only five of 15 (33%) of the adenomas from nonfamilial polyposis patients, and each of the eight (100%) adenocarcinomas of the small intestine (p < 0.001). The reactivity with the adenomas from nonfamilial polyposis patients was very focal, whereas in the adenomas with familial polyposis the reactivity was more extensive. Each of the eight carcinomas reacted strongly with mAb Das-1. Adjacent normal small intestinal mucosa did not react. Hyperplastic polyps and the carcinoids did not react with mAb Das-1. CONCLUSION: These data demonstrate a phenotypic change in small intestinal epithelium toward the colonic phenotype, particularly in familial polyposis and in adenocarcinomas. mAb Das-1 may be clinically useful in identifying small intestinal adenomas with "high risk" for malignancy, such as in familial polyposis.

Elevated serum levels of type I collagen degradation marker ICTP and tissue inhibitor of metalloproteinase (TIMP) 1 are associated with poor prognosis in lung cancer.

PURPOSE: The aim of this study was to evaluate the correlation between type I collagen degradation marker ICTP, MMP (matrix metalloproteinase)-9, and tissue inhibitor of metalloproteinase (TIMP)-1 and to compare their value as prognostic factors in lung cancer. EXPERIMENTAL DESIGN: From the sera of 141 lung cancer patients, we assessed markers of type I collagen synthesis (PINP and PICP) and degradation (ICTP) by radioimmunoassays, and we assessed MMP-9 and its tissue inhibitor TIMP-1 by ELISA. There were 62 squamous cell carcinomas, 42 adenocarcinomas, 14 small cell carcinomas, and 23 cases with other histology. Seventeen of these patients had advanced disease. Sixty-seven patients had been operated on, 33 had received radiation therapy, 7 had received chemotherapy, and the rest had received other treatment combinations. RESULTS: We examined the relationship between these markers and found a correlation between ICTP and MMP-9 (r = 0.201; P = 0.01) or TIMP-1 (r = 0.415; P = 0.00). Elevated serum concentrations of ICTP (>5 microg/liter) and/or TIMP-1 (>300 ng/ml) correlated with poor prognosis. In univariate regression analysis, ICTP had prognostic value (odds ratio, 1.6462; P < 0.03): the patients with elevated serum concentrations of ICTP (>5 microg/liter) had a 64% higher risk of dying from lung cancer than did patients with opposite values. CONCLUSIONS: Our results indicated that ICTP and TIMP-1 are good prognostic markers in lung cancer. The association between serum MMP-9 and ICTP suggests that MMP-9 could play a role in the degradation of the extracellular matrix producing ICTP in this pathological situation.

c-erbB-2 positivity is a factor for poor prognosis in breast cancer and poor response to hormonal or chemotherapy treatment in advanced disease.

The aim of this work was to evaluate the prognostic and predictive values of c-erbB-2 in breast cancer. 650 patients were enrolled. The amplification/overexpression of c-erbB-2 from fresh frozen or paraffin-embedded breast tumour tissue samples was analysed by polymerase chain reaction (PCR) technique (75%), immunohistochemically (17%) or by Southern blot analysis (8%). 126 patients (19%) were positive for c-erbB-2. 148 patients developed metastatic disease, but only 35 were positive for c-erbB-2. Positivity for c-erbB-2 was significantly associated with node positivity, large tumour size, high grade of malignancy, low receptor status, postmenopausal status, and with a shorter overall survival. In multivariate regression analysis, only tumour size and nodal involvement were risk factors for poor survival when analysed separately together with c-erbB-2 and receptor status. Metastatic patients with c-erbB-2 positivity had a significantly shorter survival and disease-free survival (DFS) than the c-erbB-2-negative patients. 29 advanced patients with c-erbB-2 positivity showed a poor response rate to hormonal, non-anthracycline-based and anthracycline-based therapies. Positivity for the c-erbB-2 is a poor prognostic factor in breast cancer, but it also emerges as predictive of the response to hormonal or chemotherapy treatment once the disease has recurred.

Type I collagen turnover and cross-linking are increased in irradiated skin of breast cancer patients.

BACKGROUND AND PURPOSE: The effects of radiation therapy on the turnover and structure of type I collagen were studied in irradiated and contralateral skin of 18 breast cancer patients without clinically evident fibrosis. MATERIALS AND METHODS: The rates of on-going type I collagen synthesis and degradation were assessed by the aminoterminal propeptide of type I procollagen (PINP) and by two different assays (ICTP and SP4) for the carboxyterminal telopeptide of type I collagen in the soluble tissue extracts, respectively. Also, TIMP-1, TIMP-2 and the MMP-2/TIMP-2 complex were measured in the tissue extracts. Insoluble skin matrices, containing the cross-linked type I collagen fibres, were heat-denatured and digested with trypsin. Then, the variants of the carboxyterminal telopeptide of type I collagen were separated by high performance liquid chromatography (HPLC). The major histidinohydroxylysinonorleucine (HHL)-cross-linked variant was quantified by the SP4 assay, and the minor pyridinoline analogue (PA)-cross-linked telopeptide was quantified by the ICTP assay. RESULTS: Both the synthesis and degradation of type I collagen were increased (r=0.906; P<0.001) on the irradiated side, whereas the concentration of the MMP-2/TIMP-2 complex was decreased. In the insoluble tissue digests, the HHL-cross-linked telopeptides of type I collagen, also, when expressed/tissue hydroxyproline, were increased in the irradiated skin. TIMP-1, TIMP-2 or PA-cross-linked telopeptides of type I collagen showed no differences between the two sides. CONCLUSIONS: Radiotherapy induces a long-term increase in the turnover of type I collagen and leads to the accumulation of cross-linked type I collagen in skin.

Radiation therapy induces tenascin expression and angiogenesis in human skin.

In analysing radiation-induced connective tissue changes, we studied tenascin expression, elastic fibres, angiogenesis and physio-mechanical properties in irradiated and contralateral healthy skin of radiotherapy-treated breast cancer patients. Skin biopsies were obtained from a radiotherapy-treated skin area and a corresponding non-treated skin area. Haematoxylin-eosin and Verhoeff stainings as well as immunohistochemical stainings for tenascin and factor VIII were performed. Epidermal and total skin thickness, together with the amount of elastic tissue calculated by computerized digital image analysis, were measured. Suction blisters were induced on both skin areas. Transepidermal water loss was analysed. Skin elasticity was also measured. Tenascin expression was found to be increased in irradiated human skin. In haematoxylin-eosin and factor VIlI-stained sections, an increase in the number of blood vessels was detected. Although skin stiffness measured by an elastometer was increased in irradiated skin, no marked difference in the elastic fibres could be found between treated and non-treated skin. The increased tenascin expression could be due to activation of cytokines as a result of irradiation. An increase in angiogenesis could be caused by an activation of angiogenetic factors by irradiation or due to direct radiation damage on blood vessel walls. Our findings suggest that the effects of irradiation tend to accumulate in the dermal parts of skin. The higher skin stiffness values measured by elastometer in irradiated skin could be due to an accumulation of dermal connective tissue as a result of irradiation.

Modulation of skin collagen metabolism by irradiation: collagen synthesis is increased in irradiated human skin.

Radiation-induced fibrosis is a common side-effect of cancer treatment. The pathophysiological events leading to fibrosis are not known in detail. We analysed the effect of therapeutic irradiation on human skin collagen synthesis, skin thickness, gelatinases and their inhibitors. Twenty randomly chosen women who had been treated for breast cancer with surgery and radiation therapy participated in the study. In each patient, the irradiated skin area was compared with a corresponding non-treated skin area. Suction blister fluid (SBF) and serum samples were analysed for the aminoterminal propeptides of type I and type III procollagens (PINP and PIIINP), tissue inhibitors of matrix metalloproteinases (MMPs) 1 and 2 (TIMP-1 and TIMP-2) and MMP-9 and MMP-2/TIMP-2 complex. Skin biopsies were analysed for PINP and immunohistochemical staining was used for PIIINP. In irradiated skin, PINP, PIIINP, TIMP-1 and MMP-2/TIMP-2 complex levels in SBF and the number of PINP-positive fibroblasts in tissue sections were significantly higher in comparison with non-treated skin. The levels of TIMP-2 in irradiated and non-irradiated skin were similar. MMP-9 could not be detected in SBF with the assay used. The serum levels of MMP-9 were higher in the treated subjects than the reference values. The serum values of PINP, PIIINP, TIMP-1, TIMP-2 and MMP-2/TIMP-2 complex were not significantly affected. These results indicate increased local collagen synthesis and accumulation of connective tissue in irradiated skin. The marked upregulation of collagen synthesis as a result of irradiation offers a possibility to treat this complication with compounds such as topical steroids which downregulate collagen synthesis.

Type XV collagen in human colonic adenocarcinomas has a different distribution than other basement membrane zone proteins.

In situ carcinomas must penetrate their own basement membrane to be classified as invasive, and subsequently infiltrate surrounding connective tissue and cross vascular basement membranes to metastasize hematogenously. Accordingly, in many studies, integral basement membrane components, including type IV collagen, laminin, and heparan sulfate proteoglycan, have been localized in a spectrum of tumors to gain insight into their role in neoplasia. A number of recently identified extracellular matrix molecules and isoforms of the aforementioned proteins have been localized to the basement membrane zone, illustrating another level of biochemical heterogeneity in these structures. As the complexity of these matrices becomes more apparent, their roles in maintaining homeostasis and in tumor biology falls into question. Of the new group of collagens localized to the basement membrane zone, type XV was the first to be characterized (Cell Tissue Res, 286:493-505, 1996). This nonfibrillar collagen has a nearly ubiquitous distribution in normal human tissues via a strong association with basement membrane zones, suggesting that it functions to adhere basement membrane to the underlying stroma. To begin investigation of this protein in malignant tumors, we have localized type XV in human colonic adenocarcinomas and compared its distribution with that of type IV collagen and laminin. Collagens XV and IV and laminin were found in all normal and colonic epithelial, muscle, fat, neural, and vascular basement membrane zones, as shown previously. In moderately differentiated, invasive adenocarcinomas, laminin and type IV collagen were sometimes observed as continuous, linear deposits around some of the malignant glands, but more often they were seen in either discontinuous deposits or were completely absent. In contrast, type XV collagen was characterized as virtually absent from the basement membrane zones of malignant glandular elements in moderately differentiated tumors. Nevertheless there were also similarities; all 3 proteins were usually present in the stroma and adjacent vascular basement membrane zones surrounding invasive glands. The loss of type XV collagen from these malignant epithelial basement membrane zones and its increased interstitial expression suggests a role for this protein in the invasive process and the possibility that it may provide a sensitive indicator of tumor invasion.

Bladder histological changes associated with chronic indwelling urinary catheter.

PURPOSE: Chronic urinary catheters induce histological changes in the bladder with time. The exact etiology of these changes is postulated to arise from inflammation and local tissue response. We elucidate the incidence of nonmalignant histological change in bladder biopsies of patients with chronic indwelling urinary catheters. MATERIALS AND METHODS: During 7 years 208 spinal cord injured patients underwent bladder biopsies as part of a surveillance program for vesical malignancy. All patients had chronic (more than 8.5 years) indwelling urethral or suprapubic catheters as definitive management for neurogenic voiding dysfunction. Biopsies were obtained from 4 to 6 sites within the bladder, including areas that were visually abnormal. All samples were routinely fixed with hematoxylin and eosin staining, and interpreted by an experienced pathologist. RESULTS: A total of 17 patients were identified with malignancy, including 10 with squamous cell carcinoma, 5 with transitional cell carcinoma and 2 with adenocarcinoma. Nonmalignant changes occurred in 48 patients (23%) with keratinizing squamous metaplasia or cystitis glandularis, each of which is considered a premalignant lesion. CONCLUSIONS: To our knowledge our study represents the largest group of spinal cord injured patients to undergo biopsy evaluation after chronic catheter use. A spectrum of inflammatory and proliferative pathological conditions were identified, which were predominantly inflammatory and squamous. The need to survey ongoing transitional mucosal changes in this population is underscored by the spectrum of histological abnormalities and the significant occurrence of malignant pathologies in our patients.

Serum type I collagen degradation markers, ICTP and CrossLaps, are factors for poor survival in lung cancer.

We investigated the prognostic value of the serum markers of type I collagen synthesis (PINP and PICP) and degradation (ICTP and CrossLaps) in 143 lung cancer patients with a local or locally advanced disease or a metastatic disease. The mean values of ICTP, CrossLaps, PINP and PICP were significantly higher in patients with bone metastases than in those without metastases or with only soft tissue metastases. The patients with ICTP < or = 5.0 micrograms/l or CrossLaps < or = 5000 pmol/l had a better prognosis. The histopathological type, the site of metastases or the stage of the disease had no influence on these results. In multivariate regression analysis, both ICTP and CrossLaps in contrast to PINP or PICP, were prognostic factors for poor survival in lung cancer patients. ICTP, CrossLaps, sedimentation rate, hemoglobin and AFOS reached separately weaker, but statistically significant values as predictors of survival with stage and operation.

Preoperative high type I collagen degradation marker ICTP reflects advanced breast cancer.

Type I collagen synthesis (PINP, PICP) and degradation (ICTP) markers were analysed from preoperative serum samples of 138 women with breast cancer (BC), 94 women with benign breast disease (BBD) and 100 healthy controls to evaluate the levels of these markers and the stage of BC at the time of diagnosis. We also compared the clinical utility of these markers in detecting BC with CA15-3 and CEA. The mean value of ICTP was statistically significantly elevated in the BC group (p < 0.001), as compared with the control group, but the elevated values in BC group were due to stage IV disease. The sensitivity of ICTP in detecting BC was 0.23, which was equal with CA15-3(0.24) or CEA(0.23). The sensitivity of both PICP and PINP for diagnosing BC was poor, but a tendency to higher serum levels of PINP and low PICP/PINP ratio was detected in patients with advanced stage IV disease. These results indicate that high preoperative serum levels of ICTP are associated with advanced BC, but like CA15-3 and CEA, its clinical value in diagnosing purpose is poor.

New lethal disease involving type I and III collagen defect resembling geroderma osteodysplastica, De Barsy syndrome, and Ehlers-Danlos syndrome IV.

We describe the clinical findings and biochemical features of a male child suffering from a so far undescribed lethal connective tissue disorder characterised by extreme hypermobility of the joints, lax skin, cataracts, severe growth retardation, and insufficient production of type I and type III procollagens. His features are compared with Ehlers-Danlos type IV, De Barsy syndrome, and geroderma osteodysplastica, as these disorders show some symptoms and signs shared with our patient. The child died because of failure of the connective tissue structures joining the skull and the spine, leading to progressive spinal stenosis. The aortic valve was translucent and insufficient. The clinical symptoms and signs, together with histological findings, suggested a collagen defect. Studies on both skin fibroblast cultures and the patient's serum showed reduced synthesis of collagen types I and III at the protein and RNA levels. The sizes of the mRNAs and newly synthesised proteins were normal, excluding gross structural abnormalities. These findings are not in accordance with any other collagen defect characterised so far.

Type I procollagen synthesis is regulated by steroids and related hormones in human osteosarcoma cells.

Change in the synthesis of type I collagen, the major extracellular matrix component of skin and bone, are associated with normal growth, tissue repair processes, and several pathological conditions. Expression of the COL 1A1 gene is regulated by transcriptional and post-transcriptional mechanisms. However, the hormonal regulation of type I collagen synthesis in human bone has not been well characterized. We have studied the influence of calcitriol, dexamethasone, retinoic acid, and estradiol on the COL 1A1 gene expression by determining the secretion of the C-terminal propeptide (PICP) and the levels of alpha 1(I) procollagen mRNA in cultured human MG-63 and SaOs-2 osteoblast-like osteosarcoma cells. Similar experiments were also performed with respect to expression of the nuclear proto-oncogenes, c-fos and c-jun, in MG-63 cells. In MG-63 cells, calcitriol stimulated the synthesis and secretion of PICP. The alpha 1(I) procollagen mRNA level was elevated with no effect on message stability, indicating a transcriptional mechanism of regulation. In contrast, dexamethasone treatment was accompanied by an accelerated rate of alpha 1(I) procollagen mRNA turnover, observed as decreased amounts of the message and the secreted PICP, implying a posttranscriptional regulation. Retinoic acid, in turn, decreased the levels of alpha 1(I) procollagen mRNA and secreted PICP by slowing down transcription of the COL1A1 gene without any effect on message stability. The ability of these hormones to regulate the alpha 1(I) transcripts was sensitive to puromycin treatment, suggesting an involvement of an induced mediator protein in the action of the hormones on the COL1A1 gene. Both dexamethasone and calcitriol rapidly but transiently increased the expression of the c-fos and c-jun proto-oncogenes. Neither proto-oncogene responded to retinoic acid treatment with significant changes in mRNA levels. Estradiol treatment was found to have no influence on type I procollagen synthesis. In SaOs-2 cells, which are not as well differentiated as the MG-63 cells, calcitriol and dexamethasone did not influence type I procollagen synthesis. Retinoic acid as well as estradiol reduced collagen gene expression in these cells. These findings suggest that hormonal effects on type I procollagen synthesis may depend on the maturational state of the osteoblastic cells that express different regulatory factors and receptors, resulting in, in each case, a finely adjusted rate of gene expression.

Aberrant type I and type III collagen gene expression in human breast cancer in vivo.

Increased synthesis and degradation of extracellular matrix components are associated with breast cancer development. This study evaluated type I and type III procollagen mRNA expression and the corresponding protein synthesis and maturation, as well as the tissue distribution of these collagens, in benign breast lesions, infiltrating ductal carcinomas, and their metastases by in situ hybridization and immunohistochemistry. In the benign lesions, the type I and type III collagen bundles were regularly organized and the expression of the corresponding mRNA was weak, indicating a relatively slow collagen turnover. In the malignant tumours, increased expression of type I and type III procollagen mRNAs was observed in the fibroblastic cells of the stroma; the malignant epithelial cells did not participate. The staining of corresponding newly-synthesized pN-collagens showed aberrant bundles in the invasive front of the malignant tumours. Newly-synthesized type I and type III procollagens were occasionally observed in fibroblastic cells, particularly in grade 2 and grade 3 tumours. Metastases of breast carcinoma resembled poorly differentiated primary tumours with respect to their collagen synthesis and deposition. The increased synthesis of fibrillar type I and type III procollagens may serve as a pathway for tumour invasion. The enhanced synthesis is associated with the formation of aberrant collagen bundles, which may be more readily degradable and may thus facilitate breast tumour invasion.

Intraluminal shunt for the thoracic aorta: blood flow and function in chronic studies.

BACKGROUND: Aortic cross-clamping during operations on the thoracic aorta may result in paraplegia or kidney failure. METHODS: A nonshunting method of repair was compared with intraluminal shunting in two groups of young pigs: the no-shunt group, which received simple aortic cross-clamping at the ligamentum for 15 minutes; and the shunt group, which received an aortic graft with a temporary intraluminal shunt and balloon occlusion of the inferior vena cava only during shunt insertion and removal. Blood flow to the spinal cord and viscera was measured with radiolabeled microspheres on days 1, 3, 5, and 7 after operation. Renal and neurologic function and histology also were studied. RESULTS: In the no-shunt group, there was hyperemia of the lumbar cord compared with the shunt group. There were no significant differences in renal cortex blood flow or creatinine clearance. Seven of 10 animals in the no-shunt group had paraplegia, compared with none in the shunt group. Histologic studies of the lower lumbar cord showed bilateral central necrosis of gray matter in the no-shunt group, but no evidence of necrosis in the shunt group. CONCLUSIONS: An intraluminal shunt allowed thoracic aorta reconstruction without paraplegia.