Complications and outcome after free flap surgery for cancer of the head and neck

We retrospectively studied 136 patients who had free flap reconstruction for cancer of the head and neck at a single centre (2008-2015) to evaluate complications, assess factors associated with them, and analyse their impact on outcome. Preoperative and perioperative data, and surgical and medical complications were recorded, and the impact of the complications on duration of hospital stay and survival were assessed. A total of 86 (63%) patients had complications. Compared with those who did not, they had a higher rate of alcohol abuse (21/86, compared with 5/50, p=0.039), longer operations (median (IQR) 565 (458-653 compared with 479 (418-556) minutes, p<0.001), and greater intraoperative loss of blood (725 (400-1150) compared with 525 (300-800) ml, p=0.042). Complications were more common in patients who had fibular flaps and T4 disease (22/86 compared with 4/50, p=0.010; 47/80 compared with 16/47, p=0.015, respectively). Those who had complications also stayed in hospital longer (median (IQR) 9 (7-12) compared with 15 (10-21) days, p<0.001). Cumulative mortality was higher in patients with late complications (those that occurred after the fourth postoperative day) (61% compared with 36%, p=0.004). In conclusion, complications in more than half the patients were related to alcohol abuse, a more complicated intraoperative course, and fibular flaps. Complications were associated with a longer hospital stay, and survival was higher in those who did not have late complications than in those who did.

Dynamic High-Field MR Imaging in Experimental Porcine Acute Pancreatitis

The effects of acute pancreatitis on MR imaging signal intensities (SIs) were determined in an experimental study at 1.0 T. Oedematous pancreatitis was induced in 9 piglets and haemorrhagic pancreatitis in 11 piglets. Each animal served as its own control for MR imaging before and after induction of pancreatitis. T1-weighted spin echo (450/15 ms) and dynamic turbo FLASH (flip angle 8°) sequences were used without contrast medium in testing the stability of the SI measurements. There was no significant difference in the SI-versus-time curves of the pancreas in piglets with oedematous and haemorrhagic pancreatitis. However, the difference in mean SIs between healthy and diseased piglets was significant. Thus, although non-contrast MR may be useful in the diagnosis of acute pancreatitis, it does not distinguish between oedematous and haemorrhagic pancreatitis.

Colposcopy referral rate can be reduced by high-risk human papillomavirus triage in the management of recurrent atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion cytology in Finland

The aim of this study was to establish whether a combination of high-risk human papillomavirus (hrHPV) testing and cervical cytology could reduce colposcopy referral among women with atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion cytology. We randomized 598 women in the Helsinki area, Finland into three study groups. Different strategies of hrHPV testing, cytology and colposcopy with biopsy were used; subsequent hrHPV test results and cytological findings were compared with histology. The rates of hrHPV positivity and CIN2+ were compared. In total, 62.5% of all samples were hrHPV-positive. Altogether 45 (12.7%) CIN2 or worse (CIN2+) lesions were found in study groups A and B. Among hrHPV-positive women the rate of CIN2+ was 19.0% (n = 43), in contrast with 1.6% (n = 2) among hrHPV-negative women (relative risk = 12.2, 95% confidence interval [CI] 3.6-81.1, P < 0.001). Among all hrHPV-negative women whose cytological findings were normal or ASCUS, dysplastic lesions were uncommon (n = 4/119, 3.4%), and all were CIN1. If these women had not been referred to colposcopy, the number of colposcopies would have been reduced by 33.6%. We conclude that hrHPV testing combined with repeat cervical cytology had a high negative predictive value in patients with recurrent low-grade cervical cytology. This could reduce the referral rate to colposcopy without jeopardizing patient safety.

A randomised controlled trial comparing sugammadex and neostigmine at different depths of neuromuscular blockade in patients undergoing laparoscopic surgery

Deep neuromuscular blockade during certain surgical procedures may improve operating conditions. Sugammadex can be used to reverse deep neuromuscular blockade without waiting for spontaneous recovery. This randomised study compared recovery times from neuromuscular blockade induced by rocuronium 0.6 mg.kg(-1), using sugammadex 4 mg.kg(-1) administered at 1-2 post-tetanic count (deep blockade) or neostigmine 50 μg.kg(-1) (plus atropine 10 μg.kg(-1)) administered at the re-appearance of the second twitch of a train-of-four stimulation (moderate blockade), in patients undergoing laparoscopic surgery. The primary efficacy variable was the time from the start of sugammadex/neostigmine administration to recovery of the train-of-four ratio to 0.9. Patients receiving sugammadex recovered 3.4 times faster than patients receiving neostigmine (geometric mean (95% CI) recovery times of 2.4 (2.1-2.7) and 8.4 (7.2-9.8) min, respectively, p<0.0001). Moreover, 94% (62/66) of sugammadex-treated patients recovered within 5 min, vs 20% (13/65) of neostigmine-treated patients, despite the difference in the depth of neuromuscular blockade at the time of administration of both drugs. The ability to provide deep neuromuscular blockade throughout the procedure but still permit reversal at the end of surgery may enable improved surgical access and an enhanced visual field.

Bone attachment to glass-fibre-reinforced composite implant with porous surface

A method has recently been developed for producing fibre-reinforced composites (FRC) with porous surfaces, intended for use as load-bearing orthopaedic implants. This study focuses on evaluation of the bone-bonding behaviour of FRC implants. Three types of cylindrical implants, i.e. FRC implants with a porous surface, solid polymethyl methacrylate (PMMA) implants and titanium (Ti) implants, were inserted in a transverse direction into the intercondular trabeculous bone area of distal femurs and proximal tibias of New Zealand White rabbits. Animals were sacrificed at 3, 6 and 12 weeks post operation, and push-out tests (n=5-6 per implant type per time point) were then carried out. At 12 weeks the shear force at the porous FRC-bone interface was significantly higher (283.3+/-55.3N) than the shear force at interfaces of solid PMMA/bone (14.4+/-11.0 N; p<0.001) and Ti/bone (130.6+/-22.2N; p=0.001). Histological observation revealed new bone growth into the porous surface structure of FRC implants. Solid PMMA and Ti implants were encapsulated mostly with fibrous connective tissue. Finite element analysis (FEA) revealed that porous FRC implants had mechanical properties which could be tailored to smooth the shear stress distribution at the bone-implant interface and reduce the stress-shielding effect.

Development of a multi-component fiber-reinforced composite implant for load-sharing conditions

Fiber-reinforced composites (FRC) have the potential for use as load-bearing orthopaedic implants if the high strength and elastic modulus of FRC implant can be matched with local requirements. This study tested the in vivo performance of novel FRC implants made of unidirectional glass fibers (E-glass fibers in Bis-GMA and TEGDMA polymeric matrix). The implant surface was covered with bioactive glass granules. Control implants were made of surface-roughened titanium. Stress-shielding effects of the implants were predicted by finite element modelling (FEM). Surgical stabilization of bone metastasis in the subtrochanteric region of the femur was simulated in 12 rabbits. An oblong subtrochanteric defect of a standardized size (reducing the torsional strength of the bones approximately by 66%) was created and an intramedullary implant made of titanium or the FRC composite was inserted. The contralateral femur served as the intact control. At 12 weeks of healing, the femurs were harvested and analyzed by radiography, torsional testing, micro-CT imaging and hard tissue histology. The functional recovery was unremarkable in both groups, although the final analysis revealed two healed undisplaced peri-implant fractures in the group of FRC implants. FEM studies demonstrated differences in stress-shielding effects of the titanium and FRC implants, but the expected biological consequences did not become evident during the follow-up time of the animal study. Biomechanical testing of the retrieved femurs showed no significant differences between the groups. The torsional strength of the fixed bones had returned the level of contralateral intact femurs. Both implants showed ongrowth of intramedullary new bone. No adverse tissue reactions were observed. Based on these favorable results, a large-scale EU-project (NewBone, www.hb.se/ih/polymer/newbone) has been launched for development of orthopaedic FRC implants.

Incidence of infections in patients with status epilepticus requiring intensive care and effect on resource utilization

Data from a six-year period were retrospectively retrieved from medical records and an intensive care unit data management system to study the impact of infections on patients with status epilepticus. Out of 161 admitted patients, 33 had a community-acquired infection and 35 acquired an infection during their hospital stay, 10 while in a ward before admission to the intensive care unit and 25 while in an intensive care unit, giving an infection rate of 42% of all admissions (68 patients). The patients with intensive care unit-acquired infection had three times longer stays in the intensive care unit than those without any infection (P<0.001), and they utilized almost four times more nursing resources than those without infections (P<0.001). Furthermore, they were more often sedated with thiopentone infusion, either alone or in combination with other drugs, than the non-infectious patients (80% vs 20%, P <0.001). Both community- and hospital-acquired infections were related to longer intensive care unit stays (P<0.001). The hospital stay of patients with hospital-acquired infection was threefold compared to that of patients without infection (P<0.001), and these patients utilized almost three times more nursing resources than those without any infection (P<0.001). Patients with infections consumed 65.5% of the intensive care unit nursing resources of status epilepticus patients. In conclusion, the infection rate of status epilepticus patients was high and nosocomial infections were associated with more severe illness, treatment escalation, prolonged hospital stay and enhanced resource utilization.

The adhesion molecule CD44v6 is associated with a high risk for local recurrence in adult soft tissue sarcomas

In many malignant diseases the expression levels of CD44 and its splice variant v6 (CD44v6) have been associated with the prognosis. The purpose of this study was to investigate the clinical significance of CD44 in adult soft tissue sarcomas (STS). 133 STS patients with a limb or superficial trunk tumour treated at the Helsinki University Central Hospital in 1987-1993 with a median follow-up time of 68 months were included in this study. The expression of CD44 and CD44v6 was determined immunohistochemically on paraffin-embedded tumour samples. 95% of the tumours expressed CD44 and CD44v6 was detected in 57%. Strong CD44 expression was associated with low grade (P = 0.04) and small tumour size (P = 0.02). In diploid tumours the CD44 expression was correlated with low S-phase fraction (P = 0.001). High expression of both, CD44 in general as well as that of CD44v6, predicted a higher risk for local recurrence (CD44: P = 0.01 and CD44v6: P = 0.05). Low CD44v6 content of the primary tumour correlated with poor survival (P = 0.02). Determining the expression of CD44 or CD44v6 in a primary STS could be a valuable tool for selecting the group of patients who might benefit from intensified local tumour treatment.

Prognostic value of tumour vascularity in metastatic melanoma and association of blood vessel density with vascular endothelial growth factor expression

Tumour angiogenesis is essential for tumour growth and metastasis. Several lines of evidence indicate that vascular endothelial growth factor (VEGF) is a major regulator both of physiological and pathological angiogenesis. In this study we assessed the blood vessel density and VEGF expression of 94 melanoma metastases of 70 patients by immunohistochemistry, utilizing antibodies against human platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31) and VEGF. The number of blood vessels ranged from 4 to 131 vessels/high power field (HPF), with a mean value of 32 vessels/HPF (+/-21) and a median of 29 vessels/ HPF. Survival since diagnosis of the primary disease and from the start of chemoimmunotherapy, as well as the disease-free survival period, was significantly shorter in the high vascularity group of patients compared with the low vascularity group (P< 0.05 and P< 0.01, respectively). A high overall expression of VEGF in the metastatic melanoma samples was observed. The degree of VEGF expression appeared to have a strong association with the blood vessel density (P= 0.017). This study demonstrates the clinical role of tumour vascularity in the prognosis of patients with metastatic melanoma. In addition, the strong association between vascularity and VEGF expression suggests a crucial role for this growth factor in the neovascularization of metastatic melanoma.

Contrast-enhanced magnetic resonance imaging for the detection of acute haemorrhagic necrotizing pancreatitis

Eleven piglets with haemorrhagic necrotizing pancreatitis and nine piglets with oedematous pancreatitis were imaged using a multi-breath-hold TurboFLASH (TR 6.5 ms, TE 3 ms, TI 300 ms, flip angle 8 degrees , three slices) pre-excited T1-weighted sequence with an IV bolus injection of gadopentetate dimeglumine (Gd-DTPA, 0. 3 mmol/kg) as a contrast agent to show dynamic contrast enhancement of the pancreas by MRI. All piglets were imaged according to the same protocol before inducing the disease. Following the IV Gd-DTPA bolus, time-enhancement curve of the pancreas during haemorrhagic necrotizing pancreatitis was significantly lower than during oedematous pancreatitis. The enhancement curves for the healthy piglets and piglets with oedematous pancreatitis did not differ significantly. Each piglet served as its own control. Because the results of this initial study are similar to those obtained with contrast-enhanced CT, we conclude that our results may encourage further clinical trials, and contrast-enhanced dynamic MRI may be an alternative to the established method of CT for diagnosing acute haemorrhagic necrotizing pancreatitis.

Stillbirths and maternal antibodies to Chlamydia trachomatis. A new EIA test for serology

OBJECTIVE

The relationship between stillbirths and infections during pregnancy.

METHODS

Antibodies to 13 different viruses and to Mycoplasma pneumoniae, Treponema pallidum, Toxoplasma gondii, and Chlamydia trachomatis, psittaci, and pneumoniae were studied from sera of 42 mothers with stillbirth and of matched case-control pregnancies.

RESULTS

Elevated antibody levels to Chlamydia trachomatis and human parvovirus B19 were observed in seven mothers with stillbirth as compared with one in matched case controls (p-0.03 and p < 0.06, Fisher's exact one- and two-tailed p values). By a novel EIA test for C. trachomatis, based on synthetic polypeptide, 15 positive cases were detected in patients compared to seven in controls. Placental calcifications and fetal growth retardation appeared more often (p < 0.001 and p < 0.05, respectively) in the C. trachomatis- associated cases than in the others. There was no significant relation between stillbirth and the other antibodies.

CONCLUSIONS

We suggest C. trachomatis as a hitherto unrecognized possible cause of still-births besides human parvovirus B19. A new EIA test for C. trachomatis, one covering all strains, is promising and makes the future assays more convenient, and may thus make it possible to reduce the rate of stillbirths.

Activation of the terminal complement cascade in renal infarction

Ischemic injury is an important cause of functional derangement in the kidney. The complement (C) system has previously been shown to be an important mediator of ischemic tissue injury in myocardial infarction. In the present study we therefore investigated the possible role of C in renal ischemic lesions. The deposition and distribution of various C components (C1q, C3c, C3d, C4, C5, C6, C9) and regulators [vitronectin, clusterin and protectin (CD59)] in human renal infarction lesions were studied by indirect immunofluorescence microscopy. Deposition of components of the terminal C complex (TCC), as well as vitronectin and clusterin, were observed throughout the infarcted areas. The strongest deposits were seen on the membranes of tubular epithelial cells and in the tubular lumina of the infarction areas, especially in the border zone between normal and infarcted tissue. Using markers for different segments of tubuli (Tamm-Horsfall glycoprotein and brush border antigens) it was possible to localize deposits of TCC predominantly to the proximal tubuli. In the glomeruli of the infarcted areas deposits of TCC were seen as a crescent-like pattern at and immediately beneath the Bowman's capsule. The expression of cell membrane-associated protectin was diminished in tubular epithelial cells of the infarction lesions. A clue for the possible mechanism of C activation in renal infarction was obtained from in vitro experiments, in which the contact of normal human serum with urine was observed to lead to the generation of TCC.(ABSTRACT TRUNCATED AT 250 WORDS)

Dynamic high-field MR imaging in experimental porcine acute pancreatitis

The effects of acute pancreatitis on MR imaging signal intensities (SIs) were determined in an experimental study at 1.0 T. Oedematous pancreatitis was induced in 9 piglets and haemorrhagic pancreatitis in 11 piglets. Each animal served as its own control for MR imaging before and after induction of pancreatitis. T1-weighted spin echo (450/15 ms) and dynamic turbo FLASH (flip angle 8 degrees) sequences were used without contrast medium in testing the stability of the SI measurements. There was no significant difference in the SI-versus-time curves of the pancreas in piglets with oedematous and haemorrhagic pancreatitis. However, the difference in mean SIs between healthy and diseased piglets was significant. Thus, although non-contrast MR may be useful in the diagnosis of acute pancreatitis, it does not distinguish between oedematous and haemorrhagic pancreatitis.

Time course of complement activation and inhibitor expression after ischemic injury of rat myocardium

Activation of the complement (C) system has been documented in both experimental and clinical studies of myocardial infarction, but the exact time course and mechanisms leading to C activation have remained unclear. Our earlier postmortem study on human beings showed that formation of the membrane attack complex (MAC) of C was associated with loss of CD59 (protectin), an important sarcolemmal regulator of MAC, from the infarcted area. The recent discovery of a rat analogue of CD59 has now allowed the first experimental evaluation of the temporal and spatial relationship between C component deposition and loss of CD59 in acute myocardial infarction (AMI). After ligating the left coronary artery in rats the earliest sign of C activation, focal deposition of C3, was observed at 2 hours. Deposition of the early (C1, C3) and late pathway (C8, C9) components in the AMI lesions occurred at 3 hours. Glycophosphoinositol-anchored rat CD59 was expressed in the sarcolemmal membranes of normal cardiomyocytes. In Western blot analysis extracts of normal rat heart CD59 appeared as a band of 21 kd of molecular weight under nonreducing conditions. Loss of CD59 in the AMI lesions was observed in association with deposits of MAC from day one onward. Our results show that C activation universally accompanies AMI in vivo. It is initiated within 2 hours after coronary artery obstruction via deposition of C3, which may be due to generation of the alternative pathway C3 convertase in the ischemic area. Deposition of C1 and late C components also starts during the early hours (2 to 4 hours) after ischemia. Subsequent loss of the protective CD59 antigen may initiate postinjury clearance of the irreversibly damaged tissue.

Co-deposition of clusterin with the complement membrane attack complex in myocardial infarction

Clusterin is a multi-functional plasma glycoprotein that has been shown to inhibit formation of the complement membrane attack complex (MAC) by preventing the association of terminal complement complexes with target cell membranes. Recent studies have suggested that complement activation is involved in the development of tissue injury of myocardial infarction. In this study we observed that clusterin is selectively deposited in the infarcted areas of human myocardium. Clusterin deposits were observed in the heart tissue of 10 patients whose infarcted lesions were 8 hr to 14 days old, but not in patients who died from other causes. Clusterin co-localized with the MAC on the surface of damaged cardiomyocytes. In normal myocardium only endothelial lining of blood vessels occasionally stained positive for clusterin. The 80,000 MW clusterin was also detected by Western blot analysis in extracts of myocardial infarction lesions, but only faintly in extracts of normal heart. As clusterin has apparently failed in protecting myocardium against complement-mediated cell injury its main role might be to participate in the clearance of damaged and necrotic tissue together with the MAC.

Intra- and peri-hepatic effects of ethanol injections in the pig liver

We studied the intrahepatic (spread and scarring) and perihepatic effects of percutaneous ethanol injection therapy and its dose-necrosis relationship in normal pig livers. Ethanol (99.5%) was injected in volumes of 0.5-2.0 ml into the livers of six pigs during laparotomy. The livers were dissected and studied histopathologically 30 min and 2 weeks after the injections. Ethanol-induced liver necrosis, the diameter of which could roughly be calculated by dividing the injected dose by 2 (inversely: volume (ml) = 2 x diameter (cm)). Two weeks after the injections all pigs showed intra-abdominal adhesions and severe intrahepatic scar formation, unlike three control pigs similarly operated on without ethanol injections. The 30-min lesions showed thin projections extending into the neighboring liver tissue. Major escape of ethanol outside the needle tip area in the liver occurred twice. Uncontrolled spread of ethanol may be a potential hazard of this treatment.

Deletion of the paired alpha 5(IV) and alpha 6(IV) collagen genes in inherited smooth muscle tumors

The gene encoding alpha 6(IV) collagen, COL4A6, was identified on the human X chromosome in a head-to-head arrangement and within 452 base pairs of the alpha 5(IV) collagen gene, COL4A5. In earlier studies, intragenic deletions of COL4A5 were detected in a subset of patients with Alport syndrome (AS), a hereditary defect of basement membranes. In some families, AS cosegregates with diffuse leiomyomatosis (DL), a benign smooth muscle tumor diathesis. Here it is shown that patients with AS-DL harbor deletions that disrupt both COL4A5 and COL4A6. Thus, type IV collagen may regulate smooth muscle differentiation and morphogenesis.

Regulation of complement membrane attack complex formation in myocardial infarction

Recent studies have suggested that the complement (C) system is involved in the development of tissue injury of myocardial infarction. As it is not known why the strictly controlled C system starts to react against autologous heart tissue, we have analyzed the expression of various membrane regulators of C (CR1, DAF, MCP, CD59, C8 binding protein) and the pattern of deposition of C components and plasma C regulators (C4b binding protein and vitronectin) in normal (n = 7) and infarcted (n = 13) human myocardium. In the infarcted myocardium deposits of the C membrane attack complex (MAC) were observed by immunofluorescence microscopy, and lesions resembling the transmembrane channels of MAC were detected by transmission electron microscopy. CD59 and C8 binding protein were strongly expressed by muscle cells of normal myocardial tissue. Little or no CR1, MCP, and DAF was observed on these cells. The assembly of MAC was accompanied by the deposition of vitronectin (S-protein) and C4b binding protein in the infarcted areas of myocardium. In accordance with our earlier results the expression of CD59 but not of C8 binding protein was clearly diminished in the lesions. The results show that C8 binding protein, vitronectin, and C4b binding protein do not prevent complement attack against the infarcted myocardium but rather become codeposited with the MAC. Ischemia-induced transformation of nonviable cells into complement activators, acquired loss of resistance to the MAC by shedding of CD59, and recruitment of multifunctional serum proteins by MAC could thus constitute a general process aimed at the clearance of injured tissue.

Prenatal diagnosis of diastrophic dysplasia with polymorphic DNA markers

Ultrasonography is a non-invasive method for prenatal detection of diastrophic dysplasia (DTD) in the second trimester of pregnancy. As there is a need for genetic counselling as early as possible we wished to develop a method based on molecular analysis. Five fetuses in families with a previous history of DTD were studied by typing them and their relevant family members for DNA markers closely linked to the DTD gene. The DNA analyses predicted that three of the fetuses were unaffected and two affected. These results were concordant with those obtained by ultrasonography, and the phenotype of the fetus was correctly predicted in all cases. DNA analysis provides a reliable means of prenatal diagnosis in the first trimester of pregnancy.

Basement membrane and interstitial matrix components form separate matrices in heterokaryons of PYS-2 cells and fibroblasts

In order to gain further understanding of the spatial organization of interstitial and basement membrane matrices, we studied the expression of the interstitial matrix protein, fibronectin, and the basement membrane protein, laminin, in heterokaryons formed by the fusion of normal fibroblasts and teratocarcinoma-derived epithelial PYS-2 cells. These heterokaryons showed various distributions of the matrix proteins depending on the proportions of the different parental cell nuclei within the cytoplasm of the cell. Heterokaryons containing equal numbers of fibroblast and PYS-2 cell nuclei showed an abundant laminin matrix subcellularly and only minor amounts of fibronectin matrix at the periphery of the cells. Similar results were obtained in heterokaryons containing an excess of epithelial cell nuclei. In heterokaryons containing an excess of fibroblast nuclei, on the other hand, laminin matrix was reduced and a fibrillar fibronectin matrix was seen also on top of the cell body. The results suggest a gene dosage-type of effect on the expression of these proteins. Furthermore, extracellular laminin and fibronectin matrices did not codistribute around the heterokaryons but the two proteins were assembled into separate structures. The lack of codistribution of fibronectin and laminin matrices in heterokaryons suggests that the molecular interactions, which determine the assembly of basement membrane and interstitial matrices in these cells are highly type-specific. Similar mechanisms may also operate in the assembly of extracellular matrices in vivo.

Loss of expression of protectin (CD59) is associated with complement membrane attack complex deposition in myocardial infarction

BACKGROUND

Protectin (CD59) is a recently discovered inhibitor of the complement membrane attack complex (MAC). In the present study we investigated expression of protectin in human heart and examined the relationship between MAC deposition and protectin in myocardial infarction.

EXPERIMENTAL DESIGN

Myocardial tissue specimens were obtained at autopsy from patients who had died of myocardial infarction (n = 10) or other causes (n = 5). MAC and protectin were detected by indirect immunofluorescence microscopy analysis in the heart sections by using antibodies against individual components of MAC, MAC neoantigens and protectin. Myocardial protectin was purified by affinity chromatography and compared with the previously characterized erythrocyte and urinary protectins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, N-terminal amino acid sequencing, and testing its ability to bind to the terminal complement complex. The possible glycophosphoinositol-type anchorage of protectin in the heart was examined by treating myocardial sections with glycophosphoinositol-specific phospholipase C.

RESULTS

Immunoblotting and immunofluorescence analysis showed expression of protectin in the sarcolemmal membranes of normal myocardium. Protectin purified from normal human heart tissue had the same molecular weight and N-terminal amino acid sequence as CD59 purified from urine. In sucrose density ultracentrifugation analysis it was observed to bind efficiently to the SC5b-8 complex. In normal myocardium the expression of CD59 was sensitive to treatment with glycophosphoinositol-specific phospholipase C. The expression of CD59 was lost or clearly diminished in infarcted lesions aged 1-14 days. Loss of CD59 expression was accompanied by concomitant deposition of the MAC within the CD59-negative lesions. In border areas between an infarcted lesion and normal tissue, CD59 often appeared in small vesicles, suggesting shedding as a possible mechanism for its removal.

CONCLUSIONS

Glycophosphoinositol-anchored CD59 is expressed in the sarcolemmal membranes of normal heart but lost from infarcted myocardium. Acquired loss of resistance to autologous complement and subsequent complement attack may thus be involved in the pathophysiology of myocardial infarction.

Müllerian adenosarcomalike tumor of the seminal vesicle. A case report with immunohistochemical and ultrastructural observations

A müllerian adenosarcomalike tumor of the seminal vesicle is described in a 49-year-old man. The tumor occupied the entire right seminal vesicle and adhered to the right lobe of the prostate, in the area adjacent to the seminal vesicle. The tumor was also adherent to the rectum. Microscopically, the cells were seen to invade the prostatic tissue. The tumor consisted of a highly cellular stroma with spindle-shaped pleomorphic cells, suggesting the diagnosis of a low-grade sarcoma. In addition, dilated cystic spaces lined by columnar epithelium were seen. Immunohistochemically, most tumor cells showed positivity for vimentin, desmin, and muscle-specific actin, suggesting smooth-muscle cell differentiation. Furthermore, electron microscopy also demonstrated smooth-muscle differentiation of the tumor cells. The patient has been disease-free for 48 months since undergoing a cystoprostatetectomy.

The complete cDNA and polypeptide sequences of human erythroid alpha-spectrin

Overlapping human erythroid alpha-spectrin cDNA clones were isolated from lambda gt11 libraries constructed from cDNAs of human fetal liver and erythroid bone marrow. The composite 8001-base pair (bp) cDNA nucleotide sequence contains 187-bp 5'- and 528-bp 3'-untranslated regions and has a single long open reading frame of 7287 bp that encodes a polypeptide of 2429 residues. As previously described (Speicher, D. W., and Marchesi, V. T. (1984) Nature 311, 177-180), spectrin is composed largely of homologous 106-amino acid repeat units. From the amino acid sequence deduced from the cDNA, alpha-spectrin can be divided into 22 segments. Segments 1-9 and 12-19 are homologous and can therefore be considered repeats; the average number of identical residues in pairwise comparisons of these repeats is 22 out of 106, or 21%. Of these 17 repeats, 11 are exactly 106 amino acids in length, whereas five others differ from this length by a single residue. Segments 11, 20, and 21, although less homologous, appear to be related to the more highly conserved repeat units. The very N-terminal 22 residues, segment 10, which is atypical both in length and sequence, and the C-terminal 150 residues in segment 22 appear to be unrelated to the conserved repeat units. The sequence of the erythroid alpha-spectrin polypeptide chain is compared to that of human alpha-fodrin and chicken alpha-actinin to which it is related. alpha-Spectrin is more distantly related to dystrophin.

Distribution of merosin, a laminin-related tissue-specific basement membrane protein, in human Schwann cell neoplasms

The expression of merosin and laminin was studied in human schwannomas, plexiform neurofibromas, and malignant schwannomas immunohistochemically using monoclonal antibodies. Merosin is a unique novel tissue-specific basement membrane protein found in basement membranes of trophoblast, striated muscle, and Schwann cells. Merosin is related to laminin, another basement membrane protein with which it shows a homologous C terminal domain. In schwannomas, merosin was only found in areas where tumor cells were in contact with stromal or vascular tissue. Laminin, however, was present in all tumor cell basement membranes. In plexiform neurofibromas large amounts of both merosin and laminin were seen in Schwann cell basement membranes. Very little of either protein was found in malignant schwannomas. Thus merosin is present almost exclusively in highly differentiated Schwann cell neoplasms, and its distribution is more restricted than that of laminin. The expression of merosin in plexiform neurofibromas and in the schwannoma cells juxtaposed to the mesenchymal cells suggests that this protein is induced epigenetically in well-differentiated cells in contact with connective tissue or vascular components.

Expression of merosin, a tissue-specific basement membrane protein, in the intermediate trophoblast cells of choriocarcinoma and placenta

Merosin is a novel tissue-specific basement membrane-associated protein found in basement membranes of trophoblast, striated muscle and Schwann cells. In placental extracts, the immuno-reactivity for merosin was detected in a protein band of 80 kilodaltons, and a 65 kilodalton polypeptide fragment of merosin could be isolated from proteolytic digests of placenta. In the present study, we describe the expression of merosin in human choriocarcinomas and normal placentas using immunoperoxidase staining of paraffin-embedded tissues. All five choriocarcinomas studied show immunoreactivity for merosin. Tumor cells, exhibiting the morphology typical of the intermediate trophoblast, stained distinctly for merosin. The cytotrophoblast and syncytiotrophoblast cells in these tumors showed negligible or no staining. In second and third trimester human placentas, merosin immunoreactivity was found in large extravillar mononuclear trophoblast cells of the basal plate as well as in the trophoblast basement membranes of the chorionic villi. The results indicate that merosin is mainly expressed in the intermediate trophoblast cells of both neoplastic and normal origin, whereas almost no expression is seen in cytotrophoblast and syncytiotrophoblast. Consequently, it is suggested that the intermediate trophoblast may represent a third, independently differentiated trophoblastic cell type.

The expression of extracellular matrix and cytoskeleton in fused cells

In the present paper results from our studies on the expression and regulation of the differentiated normal and transformed epithelial and fibroblastic phenotypes are reviewed. The expression of the extracellular matrix- and basement membrane-associated proteins, fibronectin and laminin, and different intermediate filament proteins were studied in different fused cells. Heterokaryons and cytoplasmic hybrids (cybrids) were formed by fusing normal or malignant epithelial cells with normal fibroblasts or malignant glial cells. No differences were observed in the expression of these phenotypic markers between unfused parental cells and the corresponding homokaryons. Thus, the fusion process itself does not cause changes in the expression of these phenotypic markers. In heterokaryons formed after fusion of normal or malignant epithelial cells with normal fibroblasts or malignant glial cells, two or even three different types of intermediate filaments could be co-expressed. Thus, no suppression of the expression of the various intermediate filaments is caused by the non-homologous parental cell. Expression of the extracellular matrix proteins, fibronectin and laminin, on the other hand, could be extinguished by cells and cytoplasts not expressing fibronectin matrix, such as transformed fibroblasts and HeLa cells. These results support the role of transacting regulatory factors controlling the expression of the different extracellular matrix proteins. Alternatively, the results can be explained by changes in the distribution and concentration of the extracellular matrix receptor proteins in the fused cells.

Cloning and nucleotide sequence of a mouse erythrocyte beta-spectrin cDNA

A rabbit monospecific antibody for mouse beta-spectrin was used to screen a mouse anemic spleen cDNA expression library. A mouse beta-spectrin cDNA clone was isolated and identified by its ability to make mouse beta-spectrin-like antigens in Escherichia coli. This clone was used to probe total RNA from various mouse tissues. Anemic spleen RNA showed two strongly hybridizing RNA species of approximately 6 and 8 kb. Two very faintly hybridizing bands of about 6 kb and 10 kb could also be seen in total mouse brain RNA. All of these bands could be detected after hybridization under both stringent and nonstringent conditions. This suggests that erythroid beta-spectrin may also be expressed in the brain. No bands could be detected in kidney, liver, or spleen RNA. Southern blot analysis of mouse genomic DNA showed a single hybridizing band after digestion with several restriction endonucleases even under nonstringent conditions. Nucleotide sequencing of the cDNA insert revealed almost complete identity between the N-terminus of the deduced amino acid sequence of the cDNA clone and the C-terminal 15 amino acids of a peptide derived from the beta-8 repeat unit of human erythrocyte beta-spectrin. The deduced amino acid sequence contained most of the conserved amino acids characteristic of the 106 amino acid repeat unit first found in human alpha-spectrin and thus provides the first evidence for a complete 106 amino acid repeat unit structure in beta-spectrin.

Assignment of mouse beta-spectrin gene to chromosome 12

The structural gene for the beta-subunit of the mouse erythrocyte spectrin, hereinafter designated as Sp-b, was assigned to the mouse chromosome 12. This assignment was made by Southern analysis of genomic DNA from mouse X Chinese hamster hybrid cells using cloned mouse erythrocyte beta-spectrin cDNA as a probe. In the PstI-digested genomic hamster cell DNA a single band of 2.0 kb was detected, whereas PstI-digested mouse DNA gave a band of 4.2 kb, when probed with the mouse erythroid beta-spectrin cDNA clone. This allowed us to analyze a panel of mouse X Chinese hamster somatic cell hybrids to map this gene to chromosome 12. Interestingly, this assignment is different from that observed for the alpha-subunit of spectrin, which has been mapped to chromosome 1 in mouse. These results serve as a basis for further genetic characterization of the mouse hemolytic anemias.

Expression of fibronectin matrix in cybrids of fibroblasts and epithelial cells

The pericellular fibronectin matrix of human fibroblasts is lost when they are fused with normal or malignant cells, which do not produce fibronectin matrix. In the present study we have investigated whether also the cytoplasmic fraction of fibronectin-negative HeLa or MDCK cells can cause this effect. Enucleated epithelial cells (cytoplasts) were therefore fused with norman human fibroblasts. Fibronectin expression of the resulting cytoplasmic hybrids (cybrids) was studied by the indirect immunofluorescence technique. Three hours after fusion cybrids formed between fibroblasts and enucleated epithelial cells showed fibronectin matrix expression clearly weaker than that seen on the intact fibroblasts. An accumulation of fibronectin matrix was observed in the cybrids, analogously to the intact fibroblasts, and already 12-24 h after fusion the cybrids showed a fibronectin matrix expression similar to that of the fibroblasts. No fibronectin matrix was detected in the epithelial cells or their cytoplast. Our results indicate that cytoplasmic factors from epithelial cells are able to cause an initial suppression in the formation of fibronectin matrix. However, the cytoplasts are not capable of causing a long-term effect on the fibroblasts.

Expression and distribution of vimentin and keratin filaments in heterokaryons of human fibroblasts and amnion epithelial cells

The expression of intermediate filaments of the keratin- and the vimentin-type was studied in heterokaryons of human fibroblasts and amnion epithelial cells by immunofluorescence microscopy. Fibroblasts and their homokaryons showed a fibrillar, vimentin-specific fluorescence throughout the cytoplasm but were negative when stained for keratin. Amnion epithelial cells and their homokaryons, on the other hand, showed a keratin-specific fibrillar staining, and only some of them contained also detectable vimentin. When suspended epithelial cells were fused with adherent fibroblasts, keratin fibrils spread within 3 h into the fibroblasts, intermixing with the vimentin fibrils. 1-3 d after fusion, both vimentin and keratin filaments were expressed as typical fibrillar cytoplasmic arrays, and the distribution of keratin in heterokaryons resembled closely that of vimentin. A typical cell-to-cell arrangement of keratin fibrils, seen in cultures of amnion epithelial cells, could also be found between heterokaryons. Treatment of the cultures with vinblastine sulphate induced coiling of the vimentin filaments in both homo- and heterokaryons, whereas the keratin organization was only slightly affected. Our results show that both vimentin and keratin filaments are incorporated into the cytoskeleton of heterokaryons formed between fibroblasts and epithelial cells, and that they behave in the same way as in their parental cells. Both epithelial and fibroblastic characteristics thus appear to the coexpressed in such heterokaryons.

Characterization of storage material in cultured fibroblasts by specific lectin binding in lysosomal storage diseases

The lysosomal storage material in cultured fibroblasts from patients with various lysosomal storage diseases was characterized by fluorescence microscopy using lectins specific for different saccharide moieties. In normal fibroblasts and cultured amniotic fluid cells lectins specific for mannosyl and glucosyl moieties, Con A and LcA gave a bright perinuclear cytoplasmic staining corresponding to the localization of endoplasmic reticulum in the cells. All other lectins stained the Golgi apparatus as a juxtanuclear reticular structure. In fucosidosis fibroblasts, only lectins specific for fucosyl groups LTA and UEA, distinctly stained the lysosomal inclusions. The lysosomes in mannosidosis fibroblasts did not react with Con A and LcA, both specific for mannosyl moieties of glycoconjugates, but were brightly labeled with WGA, a lectin specific for N-acetyl glucosaminyl moieties. In I-cell fibroblasts, the numerous perinuclear phase-dense granules, representing abnormal lysosomes, were labeled with every lectin used. In fibroblasts from patients with Salla disease, a newly discovered lysosomal storage disorder, the lysosomes were brightly stained only with LPA, indicating the presence of increased amounts of sialic acid residues in the lysosomal inclusions.

Subcellular compartmentalization of saccharide moieties in cultured normal and malignant cells

We studied subcellular localization of saccharide moieties in cultured normal and malignant cells fixed in paraformaldehyde and treated with a nonionic detergent, using lectins specific for various surgar residues as probes in fluorescence microscopy. In normal cells, concanavalin A and Lens culinaris agglutinin, specific for mannose-rich carbohydrate cores in glycoproteins, labeled the endoplasmic reticulum as a wide perinuclear region. Other lectins, on the other hand, stained the Golgi apparatus as a juxtanuclear reticular structure. A similar compartmentalization was also seen in all malignant cells studied, although the Golgi apparatus in these cells was distinctly vesicular in appearance. Our results indicate that saccharide moieties in both normal and malignant cells are similarly compartmentalized, and thus speak in favor of a unidirectional subcellular flow for both membrane and secreted glycoconjugates.

Fibronectin expression is determined by the genotype of the transformed parental cells in heterokaryons between normal and transformed fibroblasts

The expression of fibronectin, a cell surface-associated transformation-sensitive glycoprotein, was studied in hetero- and homokaryons of normal and SV40-transformed human fibroblasts. In immunofluorescence, fibroblast homokaryons had an intense surface-associated and intracelluar fibronectin fluorescence similar to that of normal fibroblasts. Transformed cells and their homokaryons had a minimal surface-associated and a weak intracellular fibronectin fluorescence. In heterokaryons formed between transformed and normal fibroblasts, the expression of fibronectin fell within 24 h to the level of the transformed cell homokaryons. The change was detectable already at 3 h after fusion and was gene-dose dependent. These results show that the transformed genotype determines fibronectin expression in the heterokaryons.

Fluorescent antibodies and lectins stain intracellular structures in fixed cells treated with nonionic detergent

Nonionic detergent (NP40) treatment of paraformaldehyde-fixed normal and SV40-transformed human fibroblasts resulted in intracellular penetration of two chosen fluorescent antibodies and Concanavalin A (Con A). After the detergent treatment nuclear SV40 T antigen, cytoplasmic fibronectin glycoprotein and Con A binding sites could be visualized in fluorescence microscopy. The lowest NP40 concentration which made fixed cells permeable was 0.05%. The morphology of cells was preserved better by this new method than by conventional fixation methods, such as acetone treatment. In scanning electron microscopy the surface of the fixed NP40-treated cells had only small rugosities and fine pores. The subsurface cytoskeleton especially was well preserved and had a more distinct fine structure. The improved morphology made it possible to detect a similar distribution of fibronectin and Con A binding sites in the perinuclear endoplasmic reticulum regions.