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PubMedDate not supplied

Medicinal products: regulation of biosynthesis in space and time.

We live in a "Demon-Haunted World". Human health care requires the ever increasing resistance of pathogens to be confronted by a correspondingly fast rate of discovery of novel antibiotics. One of the possible strategies towards this objective involves the rational localization of bioactive phytochemicals. The conceptual basis of the method consists in the surprisingly little known gearings of natural products with morphology, ecology and evolution of their plant source, i. e. an introspection into the general mechanisms of nature.

Biological Factors↗
PubMed1996

The relationship between the palatal form and the maxillary sinus in orang-utan.

The relationship between the palatal form and the maxillary sinus was studied in 40 skulls of male and female Bornean orangutans (Pongo satyrus borneensis) ontogenetically. Univariate analyses of the measurements of the palate and the maxillary sinus showed that the sexual dimorphism appeared earlier in palatal length than in the maxillary sinus volume. Bivariate statistical analyses, including correlation and linear regression analyses, revealed close relationships between the characteristics of the palate and the maxillary sinus for both the growth period and the adult status. Partial correlation coefficients showed, however, that these relations were highly influenced by the skull size. Except significant correlations between the maxillary sinus width and the palatal volume in the adult status, all partial correlation coefficients were clearly below the Pearson's correlation coefficients. In contrast to the situation in humans, this study suggests that under physiological conditions the influence of the palatal form on the maxillary sinus size in the orang-utan is very small. Alterations of the craniofacial morphology during the evolution of the hominids, such as facial reduction and decrease of the maxillary sinus size, are considered important factors which led to changes of the relations between the palatal form and the maxillary sinus.

Animals↗
PubMed1985

Neuroendocrine skin carcinoma coexpressing cytokeratin and neurofilament proteins.

Neuroendocrine (Merkel cell) carcinomas of the skin have been recognized as such for several years. Given the reported wide variability in the morphology and clinical evolution of these tumors, the notion that may they comprise several variants rather than a single type has been advocated. Electron microscopy has played a key role in the early recognition of these tumors while immunohistochemical studies for various neuroendocrine markers have facilitated their subsequent diagnosis and improved our understanding as to their complexity by the demonstration of immunoreactivity for NSE (neuron specific enolase) and a number of neuropeptides. There has also been considerable interest in the study of the cytoskeletal intermediate filament complement of neuroendocrine neoplasms in general and of those of the skin in particular. Early reports indicated that neuroendocrine skin carcinomas had neurofilaments while subsequent investigations determined that they had cytokeratin. However, more recent studies have indicated that at least some neuroendocrine skin carcinomas could in fact coexpress both aforementioned classes of intermediate filament proteins. This brief report is presented to confirm the latter investigations.

Carcinoma↗
PubMed1999

Phylogeny and evolution of the Betulaceae as inferred from DNA sequences, morphology, and paleobotany.

Phylogeny of the Betulaceae is assessed on the basis of rbcL, ITS, and morphological data. Based upon 26 rbcL sequences representing most "higher" hamamelid families, the Betulaceae are monophyletic, with Casuarinaceae as its sister group, regardless of whether the outgroup is Cunoniaceae, Cercidiphyllaceae, Hamamelidaceae, or Nothofagus. Within the Betulaceae, two sister clades are evident, corresponding to the subfamilies Betuloideae and Coryloideae. However, with only 13 phylogenetically informative sites, the rbcL sequences provide limited intra-subfamilial resolution. Internal transcribed spacer (ITS) sequences provided 96 phylogenetically informative sites from 491 aligned sites resulting in a single most parsimonious tree of 374 steps (consistency index = 0.791) with two major lineages corresponding to the two traditional subfamilies: Betuloideae (Alnus, Betula) and Coryloideae (Corylus, Ostryopsis, Carpinus, Ostrya). This arrangement is mostly consistent with those from rbcL and morphology and is greatly reinforced by analyses with the three data sets combined. In the Coryloideae, the Ostryopsis-Carpinus-Ostrya clade is well supported, with Corylus as its sister group. The sister-group relationship between Ostryopsis and the Carpinus-Ostrya clade is well supported by ITS, rbcL, and morphological data. Phylogenetic relationships among the extant genera deduced by these analyses are compatible with inferences from ecological evolution and the extensive fossil record.

Journal Article↗
PubMedDate not supplied

[Expression of epithelial oncoproteins in large intestine neoplasms].

The high incidence of the colorectal cancer in the industrialized countries has drawn the interest of the scientific community to detect and investigate its morphologic precursors. Growth factors and oncoproteins could be useful to investigate the morphologic and biologic evolution of precancerous lesions of the large bowel. Therefore the Authors report the results obtained from 30 selected patients with hyperplastic and adenomatous polyps, and different histotypes of colorectal cancer, investigated using the EGF-r and p62 protein expression. The results show the potential usefulness of such markers to evaluate the biology of intestinal tumors.

ErbB Receptors↗
PubMed2004

Morphological changes and outer membrane protein patterns in Helicobacter pylori during conversion from bacillary to coccoid form.

Conversion from bacillary to fully coccoid form via an intermediate U-and V-shaped form has been described in prolonged cultures of H. pylori. This morphological transformation may be the expression of transitory adaptation to a particular environment and may play an important role in antibiotic resistance and the difficulty to eradicate the pathogen. The aim of this study was to evaluate morphological and outer membrane protein changes in H. pylori during ageing-induced conversion to coccoid morphology. We used two H. pylori strains (the reference NCTC 11639 and a fresh clinical isolate) cultivated in microaerophilic environment at 37 degrees C, monitoring their morphological and biochemical evolutions for 11 days. Microscopic examination revealed the passage from spiral to U- and V-shaped form after 5-8 days of incubation, the conversion to coccoid form and the entry into viable but non-culturable state (VBNC) between days 9 and 11. Protein pattern difference appeared at 97.4 to 45 and 30 kDa molecular weight. Biochemical tests demonstrated not only a modification of outer membrane protein profiles, but also an intra-specific variability by comparison between the two analysed strains. Our findings suggest that structural and outer membrane changes associated with coccoid transformation represent a typical response in H. pylori and may constitute a survival strategy in adverse environmental conditions.

Adaptation, Physiological↗
PubMed2005

[Thyroid nodule].

The thyroid nodule is a frequent, most often benign, chronic, multifocal and slowly progressive disease. The first line strategy is to diagnose cancerous nodules (<5%) and relies upon fine needle aspiration (FNA), a specialised technique which in trained hands has a false negative rate of below 5%. The interest to explore small thyroid nodules is controversial since the prognosis of thyroid cancer is excellent for lesions measuring less than 20 mm. Though imaging accuracy is quite limited in assessing the diagnosis of thyroid cancer, both ultrasounds (US) and thyroid scan are helpful to enhance nodular identification (>30%), to sort the nodules relevant for cytological sampling and to optimize the follow-up, the major source of health costs. Suspicious and non contributive FNAs must have a control FNA within 6 months. Nodules with a non suspicious FNA (>85%) require long term follow-up. This follow-up is mainly morphological. New or evolutive nodules, as assessed by palpation or US, will require iterative FNAs or should be considered for surgery. In patients with hyperfunctioning nodules on the scan (10 to 20%), a yearly evaluation of the TSH level is sufficient. These nodules account either for autonomously functioning ones, which slowly develop towards thyrotoxicosis, or for hyperplastic nodules frequently disclosing a lymphocytic thyroiditis. Morbidity due to thyroid autonomy is still underestimated especially in aging patients with TSH levels < or =0.60 mU/L. An algorithmic approach to the diagnostic and follow-up evaluation of thyroid nodule is suggested.

Algorithms↗
PubMedDate not supplied

[In situ carcinomas of the breast: clinical features and therapeutic strategies].

INTRODUCTION: Lobular and ductal carcinomas in situ of the breast (LCIS and DCIS) origin from the ductal-lobular unit of mammary gland, but they are characterized for different morphologic patterns and evolution. In 1980 they represent 1.4% of diagnosis in breast biopsy, less of 5% of carcinomas of the breast. Actually in 7.5% of breast biopsy an in situ carcinoma is recognized (approximating 40% of breast cancers). Our purpose is to evaluate the different available strategies in the clinic management of DCIS and LCIS and, in case of surgical treatment, which reconstructive approach obtains satisfactory breast conformation. MATERIALS AND METHODS: The study enclose 125 patients: 40 of them presented LCIS (32%) and 85 DCIS (68%). In 40 patients (32%) underposed to mastectomy was performed a reconstruction in cooperation with aesthetic surgeons. 35 of 40 women with LCIS are included in a follow-up programme, 5 of them had a bilateral mastectomy and reconstruction. RESULTS: No recurrences were observed in patients affected by LCIS. Six patients underposed to wide excision for DCIS developed local recurrence, treated by mastectomy. No recurrences were observed in patients treated initially with mastectomy. Some complications correlated to reconstruction were detected. CONCLUSIONS: One of most controversial sights in breast pathology is the understanding of biological meaning of CLIS: in facts CDIS can be considered a pre-invasive cancer, CLIS is reasonably considerable only a risk indicator for developing breast cancer but it isn't a pre-neoplastic lesion. Very important is the reconstruction of the breast to improve the quality life of patients.

Adult↗
PubMed1991

[Radio-anatomical study of the calcaneus. Accuracy of Böhler's angle measurement].

The authors have studied variations of Böhler's angle by various radiographic incidences. They have defined anatomic references of this angle on the correspondent dry bone. With the same radiographic incidences, Böhler's angle was 32 degrees. This value remained constant when X-ray incidences were modified with 15 degrees in all the directions from the external profile. Anatomic variations of the 3 references on dry bone which define this angle, were very small. Böhler's angle is therefore a good morphologic reference for evolutive study of each patient. It's variation in population needs comparative radiographic control of the opposite side.

Calcaneus↗
PubMed1991

[Epidemiological study of inflammatory periapical cysts].

We have realized an epidemiologic study of 467 inflammatory periapical cysts. We have valued: age, sex, radiographic size, localization, clinic, evolution time and morphologic aspects. Ware not agree with some authors about some morphologic description.

Female↗
PubMed1991

[Functional anatomy of the foot].

The foot is presented in all its complexity as an entity that is the result of evolution as a morphological compromise between the static and dynamic demands made upon it. The subchondral mineralization of the ankle joints and the morphology of the ligaments is described in detail. A point of particular interest is the plantar aponeurosis and the septa plantaria. Additionally, the kinematic and dynamic aspects are discussed with respect to their relationship to the whole foot. Finally, an overview of the most important vessels and topographical regions is given.

Ankle Joint↗
PubMed1990

[Acute hybrid leukemia. Review of the literature and presentation of a case].

In the last years, the development of immunophenotypic and molecular analyses allowed to recognize several cases of hybrid acute leukemia (AL), whose blast cell display both lymphoid and myeloid features. Hybrid, or mixed-lineage, AL seems to have distinct clinical manifestations and hematological findings, and is mainly characterized by resistance to chemotherapy and poor prognosis. We report on a patient with AL, which showed a very rapid switch from the lymphoblastic phenotype exhibited at presentation to a myelomonoblastic one, appeared at first relapse, and lastly progressed to an undifferentiated leukemia in the terminal phase. Together with this morphologic and cytochemical evolution, leukemic cells expressed, besides the primary early-B antigens, new immunological markers related to T-lymphocytic and myeloid lineages. Based on this observation and current understanding of the ontogenesis of hematologic malignancies, we discuss biological mechanisms which are likely to underlie hybrid leukemia.

Adult↗
PubMedDate not supplied

[Neurological follow-up of glioblastomas treated by chemotherapy. Therapeutical incidences (author's transl)].

The authors describe the essential neurological complications observed during the follow-up of glioblastomas treated by sequential chemotherapy. They were studied on the basis of clinical, isotopical, CT scanner and or anatomical data. The most frequent complications are: epilepsy, acute neurological deficiency and intracranial hypertension. The diagnostic significance of the complications are discussed. Usually, they expresse a tumour extension. However, the recurrence presents varied aspects. It can be infiltrating and extensed, multifocal, focal, cystic ou pseudocystic. In the majority of cases the morphological, topographical and evolutional characters can determine the therapeutical attitude.

Adult↗
PubMed1987

[The presence of cysts in Tritrichomonas muris].

Cysts of Tritrichomonas muris are reported. The morphology of this evolution stage is described under light and electron microscopy. The biologic and epidemiologic importance of this finding is discussed.

Animals↗
PubMedDate not supplied

In vitro culture of the proximal tubule of the bovine nephron : the fate of the histiospecific antigens and neosynthesis of an alpha-foetoprotein.

The isolation of pure tubules of the outer cortex of the foetal bovine kidney, using a previously described methods, has shown that the tubule suspension obtained is almost entirely constituted of proximal tubule fragments. The proximal cells obtained from this suspension were grown in vitro. The previously called "nephrospecific" antigens NS1-2 were shown to be strictly specific for the cells of the proximal tubule, which is an "histion" of the kidney, that is to say an ultimate unit of differentiation of this organ. The fate of these antigens, henceforth termed "histiospecific antigens" (of the proximal tubule), was followed in primary monolayer cultures of the proximal tubules, using immunodiffusion tests and immunofluorescence. A rapid decrease in this antigen content of the cells was observed during the in vitro culture. An immunoautoradiographic study demonstrated that the synthesis of these antigens was switched off in the confluent cultures. A similar autoradiographic study demonstrated that these same proximal cells at confluence synthesized a bovine alpha1-foetoprotein, which had been detected in earlier studies of kidney cortex cultures. This double antigenic shift is correlated with the in vitro evolution of some morphological markers of the proximal cells, as studied with the transmission and the scanning electron microscope. The factors responsible for these results are discussed.

Animals↗
PubMed1984

[Angiographic aspects of senile macular degeneration: spontaneous course].

Between 1971 and 1981, 45 patients (50 eyes) with a senile macular degeneration were seen at an early stage of the disease. These patients were followed for 6 to 72 months (mean follow-up 32 months). The early morphological features and evolution of the lesions were analysed by fluorescein angiography. Three different angiographic types of subretinal new vessels were identified in this study. These were: angiographically visible vascular networks (27 cases) subretinal new vessels hidden behind retinal pigment epithelium modifications (9 cases); and subretinal new vessels associated with pigment epithelial detachment (14 cases). In the first group subretinal new vessels were clearly visible on the angiogram, as a distinct network of cart wheel-like capillary plexuses which fill very early in the arterial phase. Progressive leakage of dye hides this capillary plexus during the late phase. In the second group a pigment epithelial detachment, usually identified on biomicroscopic examination, was associated with neovascularization visible as a hyperfluorescent hot spot or as an uneven hyperfluorescence on the border of the RPE detachment. Other angiographic features are a non-circular shape, irregular filling of the pigment epithelial detachment, and uneven late hyperfluorescence. In the third group, occult neovascularization was usually located behind the retinal pigment epithelium. When subretinal neovascularization was suspected by the presence of a disciform lesion, angiography, showed an irregular pattern of delayed hyperfluorescence with late leakage. These features permit putative diagnosis without precise localization. This clinical study attempted to establish the evolution and prognosis of three clinical forms of subretinal new vessels, in order to more accurately establish the indications of photocoagulation treatment.

Aged↗
PubMed1984

S-phase resistance of rat hematopoietic stem cells to 7,12-dimethylbenz(a)anthracene cytocide and its implications for leukemia development.

In the experimental rat leukemia system, induced by repeated 7,12-dimethylbenz(a)anthracene (DMBA) pulses, the sensitivity of the spleen colony-forming hematopoietic stem cells (CFU-s) to the cytocidal action of a challenging DMBA injection (35 mg/kg body weight) varied with the number of pulses already applied and the organ source of CFU-s (femoral bone marrow or spleen). Assessment of the fraction of DNA-synthesizing CFU-s with the [3H]thymidine suicide technique at the time of DMBA challenge and comparison with the 20-hr CFU-s reduction values by DMBA in vivo showed an inverse correlation (p less than 0.001). It was deduced, therefore, that S-phase CFU-s are relatively resistant to DMBA cytocide. Since initiation by chemical carcinogens has been shown to be relatively S-phase specific, S-phase-resistant cytocide would lead to a selection of initiated cells and, in the case of repeated applications, to a selection of cells with multiple successive initiation hits. Preferential differentiation and organ site of leukemia, as well as evolution in sequential morphological steps, fit this assumption.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1978

Pathology of adult respiratory distress syndrome.

The morphology and sequential evolution of the pulmonary lesions in respiratory distress syndrome have been reviewed. Reasons have been presented to support the conclusion that these lesions are in the main produced by toxic effects of oxygen rather than the underlying disease process which initiated the episode of respiratory failure. The mechanism of oxygen toxicity has been briefly reviewed. The implication of these considerations is that in any patient with acute respiratory impairment, oxygen should be used as therapy only if it is required to prevent death from hypoxia and should be used in the lowest possible effective dose. As the patient improves and arterial oxygen tension rises this dose should be promptly reduced.

Humans↗