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PubMed1997

Tactile sensor method for thoracoscopic detection of intrapulmonary nodules.

We have developed a tactile sensor which can be used to quantify the hardness of objects and applied it to thoracoscopic surgery for the localization of small invisible nodules in the lung. The hardness properties of objects can be obtained as changes in the resonance frequency of the tactile sensor (delta f). When the sensor probe is moved over the lung surface, a delta f curve is depicted on the computer screen. When the sensor tip passes the area just above a target nodule, a spike is evoked in the delta f curve. In thoracoscopic surgery, tactile sensor was employed to detect a total or 42 nodules, 32 indeterminate and 10 metastatic, in 37 patients. All except two of these detected nodules, had been preoperatively demonstrated with computed tomography. Each nodule was detected successfully by recognizing the spot on the pleura, at which the spike of delta f curve was evoked, and resected thoracoscopically. All of the indeterminate nodules were diagnosed intraoperatively; 28 benign tumors and 4 primary carcinomas. In conclusion, our tactile sensor method can be a viable alternative for thoracoscopic detection of small and invisible pulmonary nodules.

Humans↗
PubMed2005

Adverse reactions to injectable soft tissue permanent fillers.

BACKGROUND: Synthetic injectable facial fillers with a permanent effect are widely atoxic and nonimmunogenic, but they differ with respect to composition and in chemical and biologic characteristics. Yet, they all act as foreign bodies in the tissues eliciting a host response that try to remove the gel. Inflammatory nodules may develop at the sites of injection-for some fillers, many years later, for others, not. Why is that? METHODS: Biopsies were contributed by various plastic surgeons from Europe and Australia after requests were made at international congresses and workshops. The study was based on (a) 5 biopsies from unreactive tissue obtained at different times after injection of polyacrylamide hydrogel (Aquamid); (b) 28 biopsies from intermediate or late inflammatory nodules after injection of polyacrylamide hydrogel (Aquamid) (20 cases), a hyaluronic acid-polyhydroxyethylmethacrylate/ethylmethacrylate gel (Dermalive) (2 cases), and a gel consisting of polylactic acid in mannitol/carbomethoxycellulose (New-Fill) (6 cases); and (c) a review of the literature on adverse reactions after injection with permanent fillers. RESULTS: Clinically unreactive tissues after injection with Aquamid showed modest or no host reaction. Inflammatory nodules showed an increased foreign body reaction and a bacterial infection after injection with Aquamid, and a combination of moderate foreign body reaction, fibrosis, and in some cases also bacterial infection after injection with Dermalive and New-Fill. According to the literature, inflammatory nodules occur no later than 1 year after injection with polyacrylamide hydrogel, but up to 6 years after injection of combination gels (Artecol), and up to 28 years after injection of silicone gel. CONCLUSIONS: Inflammatory nodules are likely to be caused by a low-grade infection maintained within a biogfilm surrounding the hydrophobic silicone gel and the combination gels. Aquamid gel may prevent formation of a biofilm through its high water-binding capacity, explaining why late inflammatory nodules are not seen after injection of this polyacrylamide hydrogel product.

Acrylates↗
PubMed2005

Port-site metastasis: the influence of biology.

OBJECTIVE: Several surgical and technical mechanisms have been proposed for the development of port-site metastasis, but the influence of tumor and host biologic factors has not been emphasized. We present a case of a pelvic chordoma that metastasized to a prior laparoscopic radical nephrectomy port-site. METHODS: A 62-year-old woman underwent laparoscopic radical nephrectomy (LRN) for a pT1b grade 3 renal cell carcinoma, followed 6 weeks later by resection of a sacral chordoma. The incisions and areas of dissection for the two procedures were discontinuous. RESULTS: Eight months following the LRN she developed a nodule in one of the laparoscopic port-sites. The port-site metastasis was treated with wide surgical resection, which was confirmed as metastatic chordoma on histologic examination. CONCLUSION: Based on the chronological sequence and physical distance between surgical sites, only biological factors could have contributed to this port-site metastasis. This unusual case highlights the important role that tumor and host biologic mechanisms play in the development of port-site metastasis.

Carcinoma, Renal Cell↗
PubMed2003

Structural motifs in the RNA encoded by the early nodulation gene enod40 of soybean.

The plant gene enod40 is highly conserved among legumes and also present in various non-legume species. It is presumed to play a central regulatory role in the Rhizobium-legume interaction, being expressed well before the initiation of cortical cell divisions resulting in nodule formation. Two small peptides encoded by enod40 mRNA as well as its secondary structure have been shown to be key elements in the signalling processes underlying nodule organogenesis. Here results concerning the secondary structure of mRNA of enod40 in soybean are presented. This study combined a theoretical approach, involving structure prediction and comparison, as well as structure probing. Our study indicates five conserved domains in enod40 mRNA among numerous leguminous species. Structure comparison suggests that some domains are also conserved in non-leguminous species and that an additional domain exists that was found only in leguminous species developing indeterminate nodules. Enzymatic and chemical probing data support the structure for three of the domains, and partially for the remaining two. The rest of the molecule appears to be less structured. Some of the domains include motifs, such as U-containing internal loops and bulges, which seem to be conserved. Therefore, they might be involved in the regulatory role of enod40 RNA.

Base Sequence↗
PubMed1997

X-ray microanalysis of black piedra.

The elements present in the fungal structures produced by Piedraia hortae in vivo and in vitro have been investigated using electron microscopy X-ray microanalysis. Phosphorus, sulphur and calcium were detected in the nodules which developed on hair and on colonies on culture. These elements belong to the extracellular material that compacts the pseudoparenchymatous organization of the fungus. They may be present due to the capacity of melanin-like pigments to sequester ions and/or they may form part of the sulphates and phosphates of the polyanionic mucopolysaccharides that constitute the extracellular material. Environmental contaminants such as aluminium, silicon and iron were detected exclusively on the surface of the nodule. They were deposited or linked to the residual molecules produced during the breakdown of the cuticular keratin. The advantages of these techniques for elucidating the chemical nature of fungal structures are discussed.

Ascomycota↗
PubMed1991

Long-term effects in skin and thyroid after radiotherapy for skin angiomas: a French retrospective cohort study.

To evaluate the long-term effects of skin angioma irradiation, a recall programme was established which included the systematic recalculation of the radiation dose to the skin and the thyroid. 22% of the 6229 patients contacted had a dermatological examination which revealed cutaneous dystrophy in 81% of the 1137 exposed angiomas and in 39% of the 208 unexposed angiomas. The risk of dystrophy (telangiectasia, hypopigmentation, superficial and subcutaneous atrophy) was 12.1 higher (P less than 0.0001) among patients who had received a surface skin dose above 30 Gy than among those who had received a dose of 10 Gy or less. The relative risk for each dystrophy component increased significantly (P less than 0.001) with surface skin dose. Furthermore, 14 basal cell carcinomas (BCC) were observed in 12 patients from the exposed group for all quantities of radiation, with a mean latency period of 22 years. No BCC was observed for a surface skin dose below 10 Gy. Thyroid testing was done on a subgroup of 431 patients whose thyroid gland had been particularly exposed during angioma irradiation. After recalculation, the dose delivered to the gland was below 1 Gy in 98% of patients. Only 13 thyroid nodules were discovered (1 hot and 12 cold). 1 patient with a cold nodule had a malignant thyroid tumour 21 years after irradiation. He belonged to the group of 7 patients who had received a thyroid dose above 1 Gy. Although no morphological abnormality was found in 98% of the tested patients, most (92%) had a thyroid iodine content below 15 mg (the standard French value), while a raised serum thyroglobulin level (greater than 30 ng/ml) was observed in 17%. This might confer a higher risk of subsequently developing thyroid nodules.

Adolescent↗
PubMed1978

Identification of epoxide hydrase as the preneoplastic antigen in rat liver hyperplastic nodules.

A liver microsomal protein, previously referred to as preneoplastic antigen, from hyperplastic nodules of rats fed a diet containing 2-acetylaminofluorene has been identified as the enzyme epoxide hydrase [glycol hydro-lyase (epoxideforming), EC 4.2.1.63]. Purified preneoplastic antigen from hyperplastic nodules and purified rat liver microsomal epoxide hydrase are immunochemically identical on the basis of Ouchterlony double-diffusion analysis. In addition, the purified proteins have identical minimum molecular weights in sodium dodecyl sulfate/polyacrylamide gels, and both proteins catalyze the hydration of arene oxides to dihydrodiols. Chronic feeding of 2-acetylaminofluorene to rats results in a 5- to 7-fold increase in epoxide hydrase activity in rat liver. The induced level of the enzyme is maintained in developing hyperplastic nodules and hepatomas but not in the nontumor tissue after removal of the carcinogen from the diet.

2-Acetylaminofluorene↗
PubMed1996

The apical caecal diverticulum of the chicken identified as a lymphoid organ.

A peculiar structure, observed as a dome-like protrusion at the apex of the caecum, was investigated macroscopically and histologically in healthy White Leghorn chickens. It was hemispheric or spherical in shape and as it consisted of a lumen with a wall occupied by lymphoid tissue, this structure was designated the apical caecal diverticulum (ACD). ACD were detected in 25.2% of examined chickens and had a mean diameter and height of 1.9 mm and 1.2 mm respectively. Histologically, both the lamina propria mucosae and the submucosa of ACD consisted of well developed aggregated lymphoid nodules. Each nodule was covered by follicle-associated epithelium which contained cells resembling M cells. Some secondary nodules extended into the subserosa. The muscularis mucosae and the stratum circulae of the tunica muscularis disappeared near the entrance to ACD. The stratum longitudinale also gradually decreased in thickness around the entrance, becoming an extremely thin layer in the diverticulum wall. At the caecal apex, each stratum of the tunica muscularis was thinner than in the caecal body and separated into several muscle bundles. These bundles were occasionally displaced by developed lymphoid nodules, causing them to protrude into the subserosa. The high frequency of ACD suggests that caecal apex may be sites for immunological surveillance in the chicken caecum. In addition to the intense and frequent antiperistalsis at the apex suggested by Yasukawa (1959), possible causes for the formation of ACD included (1) the fragility of the tunica muscularis at the ACD, and (2) the local removal of the physical supporting structures by the development of lymphoid nodules.

Animals↗
PubMedDate not supplied

True histiocytic lymphoma with multiple skin nodules.

A 73-year-old white woman developed multiple cutaneous nodules that fluctuated in size and occasionally regressed. The tumor cells infiltrating the dermis were histiocytic by light microscopy, marker studies, and electron microscopy. Similar cells were present in a bone marrow biopsy specimen. A diagnosis of true histiocytic lymphoma was made. The case illustrates some of the problems that may arise in evaluation of clinical and pathologic findings in a patient with a proliferative disorder of histiocytes and demonstrates the contribution that electron microscopy can provide in establishing the diagnosis.

Aged↗
PubMed1987

Hepatic regenerating nodules in hereditary tyrosinemia.

Hereditary tyrosinemia is an autosomal recessive, enzymatic disorder that results in micro- and macronodular cirrhosis in early childhood. Hepatocellular carcinoma occurs in approximately one-third of affected children. We evaluated the imaging studies performed in five children with this disorder. Pathologic examination of all five of the livers revealed cirrhosis and multiple regenerating nodules; hepatocellular carcinoma was present in two of the five livers. All five patients had high-attenuation or high- and low-attenuation foci within the liver. These high-attenuation foci were not apparent as focal lesions in three of four hepatic sonograms or in one of two hepatic nuclear scans. Angiography showed tumor vascularity in one patient with a focal hepatocellular carcinoma, but was indeterminate in a second patient with severe cirrhosis and multifocal hepatocellular carcinoma. Children with cirrhosis due to tyrosinemia may develop regenerating nodules that appear as high-attenuation hepatic foci on CT scans. It is difficult to differentiate regenerating nodules from multifocal hepatocellular carcinoma in these patients.

Amino Acid Metabolism, Inborn Errors↗
PubMed2005

Prevalence of thyroid nodules in an occupationally radiation exposed group: a cross sectional study in an area with mild iodine deficiency.

BACKGROUND: Thyroid nodules and thyroid cancer occur more frequently in people exposed to radiation for therapeutic purposes, and to nuclear fallout. Furthermore, it is known that a moderate degree of iodine deficiency may be responsible for an increased prevalence of thyroid nodules, while it is suspected that radiation exposure could induce changes in thyroid autoimmunity. The iodine intake of people resident in Bari, S. Italy, is mildly deficient, which could be presumed to cause a higher prevalence of thyroid pathology. This study was conducted to evaluate the prevalence of thyroid nodules in a population occupationally exposed to radiation, in an area of mild iodine deficiency. METHODS: A cross-sectional study was designed to evaluate the prevalence of thyroid nodules in radiation exposed workers, compared with a stratified sample of non exposed workers. After giving written consent to participate in the study, all the recruited subjects (304 exposed and 419 non exposed volunteers) were interviewed to fill in an anamnestic questionnaire, and underwent a physical examination, ultrasound thyroid scan, serum determinations of fT3, fT4 and TSH, fine needle aspiration biopsy. The sample was subdivided into one group exposed to a determined quantity of radiation (detected by counter), one group exposed to an undetectable quantity of radiation, and the non exposed control group. RESULTS: The prevalence of thyroid nodules < 1 cm in diameter, defined as incidentalomas, in the exposed group with detected doses, was 11.28% in males and 9.68% in females, while in the exposed group with undetectable dose the prevalence was 10.39% in males and 16.67% in females. In the non exposed group the prevalence of incidentalomas was 9.34% in males and 13.20% in females. These prevalences were not statistically different when analysed by a multiple test comparison with the bootstrap method and stratification for sex. Instead, the prevalence of thyroid nodules > 1 cm in diameter resulted statistically different in exposed and non exposed health staff: 18.68% in non exposed males vs exposed: 3.76% (determined dose) and 9.09% (undetectable dose) in males, and 20.30% in non exposed females versus 3.23% (detected dose) and 9.52% (undetectable dose) in exposed females. There was a higher proportion of healthy staff in the exposed group than in the non exposed: (80.45% vs 68.68% in males; 80.65% vs 57.87% in females). CONCLUSION: In our study, occupational exposure to radiation combined with mild iodine deficiency did not increase the risk of developing thyroid nodules. The statistically significant higher prevalence of thyroid nodules in the non exposed group could be explained by the high percentage (22%) of people with a familial history of, and hence a greater predisposition to, thyroid disease. The endemic condition of mild iodine deficiency, demonstrated in other studies, played a major role in determining the thyroid pathology in our study groups.

Adult↗
PubMed1986

Mineralized bone nodules formed in vitro from enzymatically released rat calvaria cell populations.

Single-cell suspensions obtained from sequential enzymatic digestions of fetal rat calvaria were grown in long-term culture in the presence of ascorbic acid, Na beta-glycerophosphate, and dexamethasone to determine the capacity of these populations to form mineralized bone. In cultures of osteoblastlike cells grown in the presence of ascorbic acid and beta-glycerophosphate or ascorbic acid alone, three-dimensional nodules (approximately 75 micron thick) covered by polygonal cells resembling osteoblasts could be detected 3 days after confluency. The nodules became macroscopic (up to 3 mm in diameter) after a further 3-4 days. Only in the presence of organic phosphate did they mineralize. Nodules did not develop without ascorbic acid in the medium. Dexamethasone caused a significant increase in the number of nodules. Histologically, nodules resembled woven bone and the cells covering the nodules stained strongly for alkaline phosphatase. Immunolabeling with specific antibodies demonstrated intense staining for type I collagen that was mineral-associated, a weaker staining for type III collagen and osteonectin, and undetectable staining for type II collagen. Nodules did not develop from population I and the number of nodules formed by populations II-V bore a linear relationship to the number of cells plated (r = .99). The results indicate that enzymatically released calvaria cells can form mineralized bone nodules in vitro in the presence of ascorbic acid and organic phosphate.

Animals↗
PubMed2006

[Nodular lesions of liver parenchyma caused by pathological vascularisation/perfusion].

Nodular regenerative hyperplasia (NRH) is characterized by a non-cirrhotic micronodular transformation of the liver parenchyma. It is based on the obliteration of small portal veins. Macroregenerative nodules (MRN) develop in areas of favourable blood flow in otherwise hypoperfused liver tissue. Hypoperfusion is caused by obliteration of liver veins and/or large portal veins with the subsequent atrophy or extinction of parenchyma. The hyperperfused and sometimes rapidly growing MRN might simulate a malignant tumor in CT and MRT. Morphologically, MRN resemble FNH. In contrast to hepatocellular adenoma, they show a more or less nodular architecture with fibrous septa and ductular structures. NRH and cases of MRN without cirrhosis can indicate an extrahepatic/systemic disease causing altered liver perfusion. MRN in liver cirrhosis must be differentiated from dysplastic nodules and highly differentiated hepatocellular carcinoma by cytological and microarchitectural criteria. Focal nodular hyperplasia (FNH) can imitate liver cirrhosis, steatohepatitis, cholangitis or chronic hepatitis, if biopsy material does not include normal perilesional liver tissue. Telangiectatic FNH might resemble classic hepatocellular adenoma. Neoductular structures and septation argue for this rare subtype of FNH. Neoductular transformation of hypoperfused liver parenchyma might imitate cholangioma or cholangiocarcinoma.

Humans↗
PubMed1998

[A case of cutaneous pseudallescheriosis resembling sporotrichosis].

An 83-year-old man with aplastic anemia and steroid induced diabetes mellitus developed multiple nodules with pus on the back of his right hand and forearm. He had been treated with a daily dose of 30mg prednisolone for 2 months. These lesions had appeared a month before his visit. The histopathological findings revealed dermal abscesses containing hyphal structures, lymphocytes, histiocytes and giant cells. Grocott-Methenamine stain demonstrated abundant fungal elements. In culture, colonies grow rapidly and produce a white, cottony mycelium which later becomes gray in color. Microscopically, ovoid and pyriform conidia are produced at the ends of long slender conidiophores. On PCA agar, synnemata with small conidal heads developed at 37 degrees C but cleistothecia did not appear. The patient did not respond to itraconazole therapy, however, with hyperthermic treatment, the eruptions gradually healed. Based on these findings, this fungal infection was diagnosed as pseudallescheriosis.

Aged↗
PubMed1998

Thyroid dysfunction after mantle irradiation of Hodgkin's disease patients.

Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated.

Adult↗
PubMed1983

Dedifferentiation of a transplantable papillary thyroid carcinoma over a 15-year period.

Fischer 344 rats on a prolonged low-iodine diet developed thyroid nodules which were transplanted subcutaneously into 33 thyroidectomized rats. One graft took and gave a papillary carcinoma. Serially transplanted syngeneically at 3- to 4-month intervals, it became autonomous in third generation hosts. With electron microscopy examination it was microfollicular in year 8 and anaplastic, with totally unpolarized epithelial cells, in year 15. Basement membrane present in year 1 was no longer visible in specimens of years 8 and 15. Tight and gap junctions still present in year 8 were absent in year 15, although a few desmosomes persisted. From years 8 to 15, free ribosomes and microfilaments became more frequent, whereas the number of mitochondria and the development of the Golgi complex declined.

Animals↗
PubMed2003

[Vocal fold nodules. Risk factors in teachers. A case control study design].

Vocal nodules are structural lesions very common amongst professional voice users such as teachers. We have studied the risk factors that predispose the development of vocal nodules in teachers. Two hundred and forty-two teachers were selected: 120 with vocal nodules and 120 with normal vocal folds. Professional and personal factors as well as classroom environment were studied. A complete evaluation of the voice was performed, aerodynamic measures, tone and extension of the voice, acoustic analysis, perceptual evaluation of the voice as well as a videolaryngostroboscopy which was definitive in the diagnosis. Younger teachers with less years of teaching experience a greater have tendency to develop vocal nodules than the rest. Class-room's dryness, loudness and echo are correlated with the pathological group. The most relevant personal factors in the pathological group were previous vocal pathology, laryngeal surgery, nasal surgery and gastroesophageal reflux. Vocal intensity and vocal frequency ranks were shorter in the pathological group. We could also see that, fonatory flow was less effective in the pathological group.

Adult↗
PubMed1992

Cell proliferative activity in adenomatous hyperplasia of the liver and small hepatocellular carcinoma. An immunohistochemical study demonstrating proliferating cell nuclear antigen.

BACKGROUND: Recently, adenomatous hyperplasia (AH) of the liver, a sizable parenchymal nodule in the cirrhotic liver, has been considered a preneoplastic lesion in human hepatocarcinogenesis. METHODS: The authors evaluated cell proliferative activity by immunostaining for proliferating cell nuclear antigen (PCNA) in AH (n = 30), small hepatocellular carcinoma (HCC) (n = 14), and their surrounding regenerative nodules (SRN). RESULTS: AH was categorized histologically as ordinary or atypical. Ordinary AH (n = 8) had no hepatocellular atypia, whereas atypical AH (n = 22) was composed of atypical hepatocytes that were equivocal as to benignity and malignancy. Three atypical AH contained overt malignant foci. The PCNA labeling index of ordinary AH was lower than that of SRN and the index of atypical AH was higher than that of SRN except in two cases. The PCNA labeling index of malignant foci within atypical AH was higher than that of nonmalignant areas of atypical AH and was similar to that of small HCC. For small HCC, the PCNA labeling index was much higher than that of SRN and correlated with small HCC grades. CONCLUSIONS: These data suggest that ordinary AH is a largely developed regenerative nodule with little proliferative activity and that it is not a preneoplastic lesion; the data also indicate that atypical AH has much proliferative activity, from which malignant foci with greater proliferative activity emerge. Atypical AH with or without malignant foci may represent an early stage of multi-step hepatocarcinogenesis in humans.

Aged↗