Improvement of mesh recolonization in abdominal wall reconstruction with adipose vs. bone marrow mesenchymal stem cells in a rodent model.

BACKGROUND: Reconstruction of muscle defects remains a challenge. Our work assessed the potential of an engineered construct made of a human acellular collagen matrix (HACM) seeded with porcine mesenchymal stem cells (MSCs) to reconstruct abdominal wall muscle defects in a rodent model. METHODS: This study compared 2 sources of MSCs (bone-marrow, BMSCs, and adipose, ASCs) in vitro and in vivo for parietal defect reconstruction. Cellular viability and growth factor release (VEGF, FGF-Beta, HGF, IGF-1, TGF-Beta) were investigated under normoxic/hypoxic culture conditions. Processed and recellularized HACMs were mechanically assessed. The construct was tested in vivo in full thickness abdominal wall defect treated with HACM alone vs. HACM+ASCs or BMSCs (n=14). Tissue remodeling was studied at day 30 for neo-angiogenesis and muscular reconstruction. RESULTS: A significantly lower secretion of IGF was observed with ASCs vs. BMSCs under hypoxic conditions (-97.6%, p<0.005) whereas significantly higher VEGF/FGF secretions were found with ASCs (+92%, p<0.001 and +72%, p<0.05, respectively). Processing and recellularization did not impair the mechanical properties of the HACM. In vivo, angiogenesis and muscle healing were significantly improved by the HACM+ASCs in comparison to BMSCs (p<0.05) at day 30. CONCLUSION: A composite graft made of an HACM seeded with ASCs can improve muscle repair by specific growth factor release in hypoxic conditions and by in vivo remodeling (neo-angiogenesis/graft integration) while maintaining mechanical properties.

Human tissue allograft processing: impact on in vitro and in vivo biocompatibility.

This work investigates the impact of chemical and physical treatments on biocompatibility for human bone/tendon tissues. Nontreated and treated tissues were compared. In vitro testing assessed indirect and direct cytotoxicity. Tissues were subcutaneously implanted in rats to assess the immunological, recolonization, and revascularization processes at 2-4 weeks postimplantation. No significant cytotoxicity was found for freeze-dried treated bones and tendons in comparison to control. The cellular adhesion was significantly reduced for cells seeded on these treated tissues after 24 h of direct contact. A significant cytotoxicity was found for frozen treated bones in comparison to freeze-dried treated bones. Tissue remodeling with graft stability, no harmful inflammation, and neo-vascularization was observed for freeze-dried chemically treated bones and tendons. Frozen-treated bones were characterized by a lack of matrix recolonization at 4 weeks postimplantation. In conclusion, chemical processing with freeze-drying of human tissues maintains in vitro biocompatibility and in vivo tissue remodeling for clinical application.

Pancreatic beta-cell mass in European subjects with type 2 diabetes.

Decreases in both beta-cell function and number can contribute to insulin deficiency in type 2 diabetes. Here, we quantified the beta-cell mass in pancreas obtained at autopsy of 57 type 2 diabetic (T2D) and 52 non-diabetic subjects of European origin. Sections from the body and tail were immunostained for insulin. The beta-cell mass was calculated from the volume density of beta-cells (measured by point-counting methods) and the weight of the pancreas. The pancreatic insulin concentration was measured in some of the subjects. beta-cell mass increased only slightly with body mass index (BMI). After matching for BMI, the beta-cell mass was 41% (BMI < 25) and 38% (BMI 26-40) lower in T2D compared with non-diabetic subjects, and neither gender nor type of treatment influenced these differences. beta-cell mass did not correlate with age at diagnosis but decreased with duration of clinical diabetes (24 and 54% lower than controls in subjects with <5 and >15 years of overt diabetes respectively). Pancreatic insulin concentration was 30% lower in patients. In conclusion, the average beta-cell mass is about 39% lower in T2D subjects compared with matched controls. Its decrease with duration of the disease could be a consequence of diabetes that, with further impairment of insulin secretion, contributes to the progressive deterioration of glucose homeostasis. We do not believe that the small difference in beta-cell mass observed within 5 years of onset could cause diabetes in the absence of beta-cell dysfunction.

Is the expression of Gal-alpha1,3Gal on porcine pancreatic islets modified by isolation procedure?

AIM: The aim of this study was to study the Galactosyl alpha(1,3) Gal expression and the vascular tissue distribution prior to and after isolation of porcine pancreatic islets. METHODS: Biopsies of native pancreas were carried out in young (12-15 weeks; n = 4) and adult Landrace pigs (2 years old; n = 7). These pancreases were then digested (Liberase Porcine Islets [PI]) to obtain isolated pancreatic islets from each pancreas. Alpha Gal-specific biotinylated BS-1 isolectin B4 and von Willebrand's Factor (vWF) staining were performed for Galactosyl and vascular structure analysis, respectively. Quantitative Galactosyl expression as well as location of the vascular structure were determined using image analysis in pig islets of different sizes. RESULTS: Vascular structures and Galactosyl expression varied following the islet sizes but not the pig age. In large islets (>100 microm), capillaries were mainly located within the islets, whereas in small islets (<100 microm), 4-fold more vessels were situated at the periphery of the islets. Galactosyl expression followed a comparable distribution than vascular tissue in small and large islets. After isolation, a significant decrease of Gal staining (-49%) was observed, but Galactosyl expression remained positive within both small and large islets. CONCLUSIONS: Galactosyl expression is maintained within pancreatic islets after isolation procedure. Gal knock-out pigs could represent the solution to this hurdle.

Impact of porcine islet size on cellular structure and engraftment after transplantation: adult versus young pigs.

OBJECTIVES: To study the impact of porcine islet size on structural properties and cellular engraftment. METHODS: The endocrine structure and collagen/vascular localization in pig islets were studied before and after enzymatic isolation on the pancreas from 6 young and 6 adult Landrace pigs. Isolated islets from both pig types were transplanted under the kidney capsula of diabetic nude rats to assess cellular engraftment. RESULTS: In comparison with adult pig pancreata, a significantly greater number of small beta cells (<100 microm) were observed before and after isolation (82% vs. 32%, respectively, P < 0.005) from young pig pancreata. Small islets (<100 microm) showed a peripheral vascular structure, whereas large islets showed a more centralized vascular organization, thereby providing protection during the enzymatic digestion procedure. The islet endocrine structure was not affected by the islet size, but a loss of glucagon cells (-7.9%, P < 0.005) was observed in large isolated islets. The purity of islet preparation was better with pancreata from adult than young donors (86% vs. 64%, respectively, P < 0.05). A lack of engraftment was observed for small islets from young pig donors as compared with large islets from adult donors. CONCLUSIONS: Large and well-structured islets, mainly found in adult pig pancreata, probably possess a better potential for cellular engraftment due to centralized vascularization and collagen distribution.

Chronic aristolochic acid toxicity in rabbits: a model of Chinese herbs nephropathy?

BACKGROUND: Chinese herbs nephropathy (CHN) is a new type of subacute interstitial nephritis that is attributed to aristolochic acid (AA), which inadvertently has been included in slimming pills. The contribution of other simultaneously prescribed drugs remains disputed. In the present study, the effects of a chronic intake of AA given as a single drug was evaluated through renal histology and function in rabbits. METHODS: Female New Zealand White rabbits were injected intraperitoneally with either 0.1 mg AA/kg or with saline 5 days a week for 17 to 21 months. Body weight, renal function, and urinary excretion of glucose and low molecular weight proteins were monitored prior to sacrifice at the end of the study period. RESULTS: All animals given AA developed renal hypocellular interstitial fibrosis, which was classified into three patterns. Fibrosis was confined to medullary rays (MRs) in pattern I (N = 3), extended to the outer cortical labyrinth (OCL) in pattern II (N = 2), and eventually to the inner cortical labyrinth (ICL) in pattern III (N = 6). Fibrosis in MR and OCL was associated with mainly proximal tubular epithelial cell flattening. All treated animals displayed urothelial atypia. Three of them also developed tumors of the urinary tract. No significant pathologic changes were found in control rabbits. AA-treated animals differed from controls by an impaired growth, increased serum creatinine, glucosuria, tubular proteinuria, and anemia. CONCLUSION: The observed pattern of renal histopathological lesions and disorders of the renal function, as well as urothelial atypia and malignancy, are very reminiscent of CHN. Our observations therefore support a causal role of AA alone in the genesis of this new nephropathy.

Lesions in donor kidneys: nature, incidence, and influence on graft function.

The aim of this study was to assess the influence of kidney-donor transmitted pathology on graft function. Light and immunofluorescent microscopic findings from a surgical biopsy taken prior to transplantation from 114 cadaveric kidney donors were analyzed. Moderate to severe mesangial IgA deposits were considered consistent with IgA nephropathy. Pathological abnormalities were correlated together with donor age, number of mismatches, and type of immunosuppression by multivariate statistical analysis with the serum creatinine values from patients who experienced no acute rejection at 1 year. Serum creatinine values (n = 52) were not correlated with either non-specific light microscopic lesions or immunofluorescent deposits found in the majority of kidney donors or with changes consistent with IgA nephropathy observed in 9% of the cases. There was, however, a correlation with donor age, which was also correlated with the extent of chronic lesions (P < 0.001).

Chinese herbs nephropathy-associated slimming regimen induces tumours in the forestomach but no interstitial nephropathy in rats.

Chinese herbs nephropathy (CHN), a rapidly progressive interstitial fibrosis of the kidney, has been described in approximately 100 young Belgian women who had followed a slimming regimen containing some Chinese herbs. In 4 patients multifocal transitional cell carcinomas (TCC) were observed. Aristolochic acid (AA), suspected as the causal factor of CHN, is a well known carcinogen but its ability to induce fibrosis has never been demonstrated. The objective of this study was to evaluate the latter using doses of AA, durations of intoxication and delays of sacrifice known to yield tumours in rats. We also tested the hypothesis that a possible fibrogenic role of AA was enhanced by the other components of the slimming regimen. Male and female rats were treated orally with 10 mg isolated AA/kg per day for 5 days/week, or with approximately 0.15 mg AA/ kg per day 5 days/week contained in the herbal powder together with the other components prescribed in the slimming pills for 3 months. The animals were killed respectively 3 and 11 months later. At sacrifice, animals in both groups had developed the expected tumours but not fibrosis of the renal interstitium. Whether the fibrotic response observed in man is due to species and/or strain related differences in the response to AA or to other factors, remains to be determined. Interestingly, despite the addition of fenfluramine and diethylpropion, two drugs incriminated in the development of valvular heart disease, no cardiac abnormalities were observed.

The 'female prostate': location, morphology, immunohistochemical characteristics and significance.

Using immunostaining for prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP), we can demonstrate prostate-analogous periurethral glands (the 'female prostate') in 66.7% of 33 cases. Histomorphologically, these glands resemble strongly the male prostate glands before puberty. They remain immature throughout life from the fetal period up to advanced age obviously because of a lack of an androgenic stimulus. The glands have long ducts leading into the urethra. A proper stroma component is missing. The immunohistochemical behavior of these glands also corresponds widely to that of the male prostate glands before puberty. No indications can be found for a proper biological function.

Squamous cell carcinoma of the prostate.

Eleven case of squamous cell carcinoma of the prostate have been divided into four groups according to their histological features and natural history: a pure squamous cell carcinoma of the prostate (one case); b common prostatic adenocarcinoma with malignant squamous component after oestrogen treatment (two); c urothelial carcinoma of the prostate with malignant squamous cell metaplasia (four); and d urothelial carcinoma of the urinary bladder with squamous cell metaplasia growing into the prostate (four). The squamous portions may spread to invade the fibromuscular stroma and grow in prostatic ducts. Necrosis of comedo type and inflammatory infiltrates appeared in a number of cases. The survival times of nine patients ranged from 1 to 17 months. Squamous components were shown by immunohistochemistry to contain various keratin types, carcino-embryonic antigen and peanut agglutinin binding sites. Whenever a squamous cell carcinoma in the prostate is diagnosed histologically various possibilities as to its origin should be considered.

Morphological and immunohistochemical investigations of the utriculus prostaticus from the fetal period up to adulthood.

We investigated the utriculus prostaticus from the fetal period up to adulthood in 148 prostates. During the second half of gestation the utriculus had a simple tubular or a cystic form and was lined with metaplastic squamous epithelium which showed immunohistochemical positivity for different keratins, carcinoembryonic antigen, and peanut agglutinin binding sites. After birth, alveolar outgrowths of the utriculus developed. After puberty, the utriculus had become a complicated and variable structure. The epithelium no longer differed from that of the prostate glands either morphologically or immunohistochemically. Within the epithelium numerous endocrine cells were found containing neuron-specific enolase, chromogranin, and serotonin. The utriculus and ejaculatory ducts were embedded in a fibrous stroma with, after birth, numerous plexus-like blood vessels. This fibrous zone was peripherally bordered by a layer of smooth muscle. There was no evidence for a function of the utriculus differing from that of the prostate glands. Since the epithelium of both structures is identical immunohistochemically, the epithelium of the sinus urogenitalis most likely particpates in the lining of the utriculus during embryogenesis.

[Intramural pregnancy with vague symptoms]. / Symptomarme intramurale Gravidität.

The clinical course of an intramural pregnancy in a 28-year-old nullipara is reported. Clinical and sonographic symptoms were not specific. The diagnosis was suspected on laparoscopy. At laparotomy, evidence of incipient rupture of the uterus was found, but no intraperitoneal hemorrhage. The gestational sac was removed without opening the uterine cavum, and the localization within the myometrium was confirmed histologically. Intramural pregnancy is a rare event whose pathogenesis is not clear. Surgical treatment with conservation of the uterus is possible in some cases.

The haemochromatotic human pancreas: a quantitative immunohistochemical and ultrastructural study.

Insulin, glucagon, somatostatin and pancreatic polypeptide cells were quantified after immunoperoxidase staining in sections of pancreases obtained from nine control subjects and seven diabetic patients with primary or secondary iron overload. One was normoglycaemic, two had glucose intolerance and four presented insulin-requiring diabetes. The whole pancreas was studied, taking into account the heterogeneous distribution of the endocrine cells. In the diabetic patients, the weight of the pancreas tended to be lower. Iron overload predominated in the exocrine tissue, whereas in islets iron concentration was quite variable from case to case. At the Haemalun-Eosine staining the histological appearance of the islets was normal, their shape and size being unchanged; amyloid deposits were absent, as were atrophic islets. Immunoperoxidase staining revealed a severe reduction in the number of immunoreactive B cells in the four diabetic patients. The mass of immunoreactive B cells was calculated from their volume density and from the weight of each lobe of the pancreas. It averaged 950 mg in control subjects, 1580 mg in the normoglycaemic patient, 1010 mg in patients with glucose intolerance and 180 mg in insulin-requiring diabetic patients. The electron microscopic examination, performed in four cases, revealed that the iron deposits were restricted to B cells and associated with progressive loss of their endocrine granules. The study shows that the pancreatic islet abnormalities in iron overloaded diabetic patients are completely different from those of Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic patients. This constitutes a further argument for a specific role of iron in the pathogeny of diabetes in haemochromatotic patients.

Papillary carcinoma of the prostate, location, morphology, and immunohistochemistry: the histogenesis and entity of so-called endometrioid carcinoma.

Fifty carcinomas that were partially to completely papillary in nature were examined. According to urethroscopic and rectal palpation findings, six of the carcinomas were located centrally, 40 tumors were in the prostate proper, and four were clinical stage T0. The epithelium of the papillary portions of the tumors was dark in some instances, light in others. Immunohistochemistry revealed that 20 of 22 tumors were positive for prostatic acid phosphatase (PAP) and prostate-specific antigen (PSA). In no case was a topical relationship to the utriculus prostaticus demonstrable. The epithelium of the utriculus in seven additional patients who were not involved in this series also stained positively for PAP and PSA. Usual carcinomas of the prostate proper can develop endometrioid structures that do not differ immunohistochemically from ordinary portions of the carcinoma. Tumors located in central portions of the prostate are, in our opinion, morphologic variants of usual prostatic carcinomas, and apparently arise in prostatic ducts. We conclude that a distinction between endometrioid carcinomas and tumors of prostatic ducts does not seem justified and that papillary prostatic carcinomas should be treated like common prostatic cancer.

Immunohistochemical demonstration of cytokeratins in the human prostate.

The behaviour of keratins in the human prostate is investigated immunohistochemically by polyclonal rabbit antibodies against keratins from human stratum corneum (kit from ORTHO/Heidelberg) and compared to the behaviour of prostatic acid phosphatase (PAP) and prostate-specific antigen (PSA). In normal glands and cribriform as well as adenomatous hyperplasia only basal cells contain keratin. The secretory epithelium is keratin-negative and in contrast to the basal cells PAP- as well as PSA-positive. In prostatic ducts and utriculus prostaticus keratin is demonstrable in basal cells and urothelium. As in normal glands, the light cylindric epithelium is keratin-negative and PAP- as well as PSA-positive. The cells in atrophic glands and postatrophic hyperplasia may contain keratin as well as PAP and PSA. Urothelial and squamous metaplasia are strongly keratin-positive. PAP and PSA are not found. The cylindric epithelium of the ejaculatory ducts contains keratin at many places. PAP and PSA are not demonstrable. The utriculus does not differ from normal prostatic glands immunohistochemically. This supports the view that the epithelium of the sinus urogenitalis is involved in the embryogenesis of normal prostatic glands and the utriculus as well. Urothelial and squamous metaplasia obviously arise from basal cells which share the same immunohistochemical features. Whether the cells in atrophic glands and postatrophic hyperplasia derive from basal cells or secretory epithelium cannot be decided. The keratin composition of the prostate should be further analyzed by keratin-specific monoclonal antibodies.

[Disintegration of kidney calculi by piezoelectrically generated high-energy sound waves. Physical principles and experimental studies]. / Die Zertrümmerung von Nierensteinen durch piezoelektrisch erzeugte Hochenergie-Schallpulse. Physikalische Grundlagen und experimentelle Untersuchungen.

The recently developed equipment for extracorporeal piezoelectric lithotripsy (EPL) represents an improvement concerning the shock-wave-induced disintegration of urinary calculi. While the usual spark gap transmitter needs a focusing reflector, the piezoelectric lithotriptor is based on a self-focusing spherical bowl transmitter. The stone is detected exclusively by ultrasound. For this purpose, an integrated sector scanner is used as well as the high-energy sound transmitter itself. With the piezoelectrically generated high-energy sound pulses we have succeeded in completely disintegrating implanted stones in the renal pelvis of dogs without injuring the morphology or function of the exposed kidneys.

Papillary cystadenoma of the epididymis. Case report and review of the literature.

The only known benign epithelial tumor of the epididymis is papillary cystadenoma. Since 1921, only 39 such tumors have been published. We report on a papillary cystadenoma in a 30-year-old patient. The tumor measures 1.5 cm and is located in the head of the left epididymis. Histomorphologically, these tumors are characterized by cysts with colloid-like contents and papillary formations of light epithelium. Papillary cystadenoma can occur uni- or bilaterally, most frequently in the head of the epididymis. Age of patients ranges between 16 and 81 years with 36.6 years on average. Bilateral papillary cystadenomas are combined in 65, unilateral in 18% with Hippel-Lindau' disease. Most authors regard ductuli efferents as point of origin of these rare benign tumors.

[Malignancy grade and clinical stage T0-T3 in prostate cancer]. / Malignitätsgrad und klinisches Stadium T0-T3 beim Prostatakarzinom.

The frequency of malignancy grade I-III (grading system according to Böcking and Sommerkamp, 1980) and of clinical stages T0-T3 in 393 unselected prostatic carcinomas (227 punch biopsies and 166 transurethral resections) were investigated over a period of 2 years. G III carcinomas were represented most frequently in the whole material (54%) as well as in punch biopsies (62%). G I carcinomas with a favorable prognosis make up 20% of the tumors in the whole material and only 10% in punch biopsies. In contrast, 54.9% of incidental carcinomas (T0) are G I tumors, 18.6% G III carcinomas with an unfavorable prognosis. The advanced clinical stages T2 and T3 predominate in the whole material with 62.4%, compared to stages T0 and T1 comprising 37.6%. Malignancy grade and clinical stage are clearly correlated in the whole material. In incidental carcinoma, there is also a correlation between malignancy grade and histologic extension. The percentage of higher malignancy grades G II and G III increases with age. This is true for incidental carcinoma as well. The findings emphasize the prognostic significance of the grading system.

Diagnosis and grading of malignancy in squamous epithelial lesions of the larynx with DNA cytophotometry.

For diagnostic purposes 14 histologically benign, 15 dysplastic, and 16 malignant squamous epithelial lesions were subjected to DNA cytophotometry. Results were computed according to an algorithm for DNA diagnosis and grading of malignancy. In cases of unequivocally malignant or benign lesions all DNA diagnoses agreed with the histologic diagnoses. In one case the allegedly faulty DNA diagnosis of cancer was proven to be correct on clinical follow-up. Within the group of histologically mild to moderate dysplasias the algorithm identified four cases as malignant that were proved to be malignant either in the follow-up or at another site of the same lesion. With the aid of the DNA malignancy grade two groups of patients with squamous epithelial carcinomas of the larynx could be discerned with a highly significant difference according to their survival times.