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PubMed2006

The frequency of multiple paternity suggests that sperm competition is common in house mice (Mus domesticus).

Sexual selection is an important force driving the evolution of morphological and genetic traits. To determine the importance of male-male, postcopulatory sexual selection in natural populations of house mice, we estimated the frequency of multiple paternity, defined as the frequency with which a pregnant female carried a litter fertilized by more than one male. By genotyping eight microsatellite markers from 1095 mice, we found evidence of multiple paternity from 33 of 143. Evidence for multiple paternity was especially strong for 29 of these litters. Multiple paternity was significantly more common in higher-density vs. lower-density populations. Any estimate of multiple paternity will be an underestimate of the frequency of multiple mating, defined as the frequency with which a female mates with more than a single male during a single oestrus cycle. We used computer simulations to estimate the frequency of multiple mating, incorporating observed reductions in heterozygosity and levels of allele sharing among mother and father. These simulations indicated that multiple mating is common, occurring in at least 20% of all oestrus cycles. The exact estimate depends on the competitive skew among males, a parameter for which we currently have no data from natural populations. This study suggests that sperm competition is an important aspect of postcopulatory sexual selection in house mice.

Animals↗
PubMed1996

Pigmented and hyperkeratotic napkin dermatitis: a liquid detergent irritant dermatitis.

BACKGROUND: Napkin or diaper dermatitis (DD) is an inflammatory cutaneous eruption limited to the diaper area and common in the first 2 years of life. A number of clinical variants of DD have been identified. OBJECTIVE: We report a new variant of DD characterized by papyraceous skin, brownish discoloration and predilection for the depth of folds. METHODS: 15 infants and toddlers affected by this peculiar type of DD were evaluated regarding duration, localization, morphology and evolution of their dermatosis. RESULTS: This variant of DD was mainly confined to the depth of inguinal and gluteal folds and invariably associated with severe xerosis with papyraceous and glazed skin. The patients were healthy and asymptomatic and all laboratory investigations performed were normal. All patients were frequently changed and thoroughly washed with synthetic detergents with acid pH. DD improved rapidly with reduced frequency of washing and discontinuation of liquid detergents. CONCLUSIONS: We conclude that this condition is a type of irritant contact dermatitis from excessive use of lipid acid detergents.

Dermatitis, Irritant↗
PubMed1992

A new marker for early detection and indicator of progression of cancer of the bladder. Preliminary results with Ag-NOR index in 38 cases of superficial bladder cancer.

The multiform biology of superficial bladder tumors, both morphologically and evolutively, and the lack of reliable predictors of progression have led the authors to study the Ag-NOR proteins as a new marker of these tumors. It is well known that particularly the low-grade superficial tumors frequently relapse on the same histologic and proliferative module. Their potential of progression is probably present at the time of the first manifestation of the disease or it can show itself along the relapsing evolution with classic modifications translating the cellular dedifferentiation. The NOR index, set up by the authors, has several advantages: firstly, it corresponds to a functional value of normal and neoplastic cells; secondly, it can be used also with paraffin blocks. Another advantage is the semiautomatic lecture, reproducible also in the urinary cytology, mainly of low-grade tumors, reducing the number of false-negatives. The conclusion of the study of 38 cases of superficial bladder cancer has induced the authors to believe that an increased NOR index is a reliable 'marker' of their progression. Therefore, the authors suggest the use of the NOR activity for the surveillance of the urothelial disease and for a more logical therapeutic strategy.

Adult↗
PubMed2006

Effect of hydrophobic mismatch on phase behavior of lipid membranes.

We investigate the competing effects of hydrophobic mismatch and chain stretching on the morphology and evolution of domains in lipid membranes via Monte Carlo techniques. We model the membrane as a binary mixture of particles that differ in their preferred lengths, with the shorter particles mimicking unsaturated nonraft lipids and the longer particles mimicking saturated raft lipids. We find that phase separation can be induced upon increasing either the ratio J/kappa of the hydrophobic surface tension J to the compressibility modulus kappa. J/kappa determines the decay length for thickness changes. When this decay length is larger than the system size the membrane remains mixed. Furthermore, increasing the thickness relaxation time can induce transient phase separation.

Computer Simulation↗
PubMed2000

[Gestational trophoblastic diseases. Classification, epidemiology and genetic data].

Gestational trophoblastic diseases amalgamate several entities with a common denominator which is a hypersecretion of hCG: complete mole, invasive or not, partial mole or triploid syndrome, gestational trophoblastic carcinoma and trophoblastic carcinoma from the implantation site. These entities differ by their origins, their morphology, their evolution and their treatments. Complete moles are diploid and in 80% of cases, chromosomes are only from paternal origin (diandry or dispermy). Their evolution is unpredictable whatever the molecular biology or cytogenetical methods are. Partial moles, generally triploid, are much more frequent (10-20% of miscarriages) than the number of cases diagnosed during the pregnancy. In 85% of cases, two sets of chromosomes are of paternal origin. The gestational trophoblastic carcinoma is diploid and its genetic material comes from both parents. This probably excludes a direct filiation between complete mole and gestational trophoblastic carcinoma. The trophoblastic tumor from the implantation site comes from the trophoblast of the implantation site which explain why its evolution and its prognosis are totally distinct from the previous one. In this report, we successively discuss the natural history of gestational trophoblastic diseases, their epidemiology and the genetic data explaining their origins.

Adult↗
PubMedDate not supplied

[Neutropenic enteropathy associated with autoimmune diseases. A more aggressive presentation].

BACKGROUND: There is just one case report dealing with neutropenic enteropathy associated with autoimmune diseases. METHOD: An autopsy analysis of neutropenic enteropathy in autoimmune and hematologic diseases was carried on. Gross findings and slides were reviewed. A blind analysis is of the mucosal lesions in small and large intestine as well as of the clinical course was made. RESULTS: Seventeen cases of neutropenic enteropathy were found a once period of 13 years (1,068 autopsies). Fourteen cases were seen in patients with hematologic diseases and three in patients with autoimmune diseases. Acute symptoms had a 6-day evolution and were characterized by abdominal pain, diarrhea, ascitis, and fever in autoimmune diseases. Extension of colonic damage was 58 and 13% in small bowel. Cases associated with hematologic diseases had longer clinical course with fever abdominal pain and colonic lesions in 21% of the surface and small bowel lesions in 6% of the mucosa. No acute inflammatory infiltrate around the necrotic zones was observed in either group Azathioprine, steroids, methotrexate, and alkylating agents were associated to neutropenia. CONCLUSIONS: Clinical evolution and morphologic findings were more severe in neutropenic enteropathy associated with autoimmune diseases than in patients with hematologic diseases.

Adolescent↗
PubMed2002

Alignment of collagen and laminin-containing gels improve nerve regeneration within silicone tubes.

PURPOSE: Placement of extracellular matrix components has been used as a mean to enhance axonal growth across nerve long gaps repaired by tubulization. However, such matrices may impede axonal regeneration depending on its density and microgeometry. METHODS: Silicone tubes were prefilled with collagen or laminin-containing gels and implanted into a 6 mm gap, a length considered limiting for regeneration, in the mouse sciatic nerve. Gels were polymerized prior to implantation either in horizontal position or subjected to gravitational (in vertical position) or to magnetic forces to induce longitudinal alignment of the fibrils. Recovery of motor, sensory and sudomotor functions in the hindpaw was evaluated during 4 months postoperation. RESULTS: Reinnervation started earlier and achieved slightly higher levels with aligned collagen gels than with the horizontal gel. For the three groups repaired with tubes with Matrigel, there was a gradation of the functional results, reinnervation started earlier and reached higher values in matrix with magnetically-induced, longitudinal orientation than with the horizontal gel, whereas gravitational alignment followed an intermediate evolution. Final morphological evaluation showed more dense residual mass of collagen than of Matrigel at the center of the regenerate nerves. The number of myelinated fibers was increased in tubes with alignment compared to horizontal gels. CONCLUSIONS: Alignment of collagen and laminin gels within a silicone tube increases the success and the quality of regeneration in long nerve gaps. The laminin gel performed better than the collagen gel under each condition tested. The combination of an aligned matrix with embedded Schwann cells should be considered in further steps for the development of an artificial nerve graft for clinical application.

Action Potentials↗
PubMed1992

[Caput valgum in children. Natural history and treatment of a series of 17 hips that reached skeletal maturation].

The growth disturbance of the superior end of the femur which is related to a superior lateral epiphysiodesis of the femoral neck is known as caput valgum (C.V.). Most often, it appears after the treatment of a congenital dislocation of the hip (C.D.H.) which can also produce many other growth disorders of the hip. Fifteen children (seventeen hips) presenting similar evolution and morphological abnormalities have been reviewed. We performed nine surgical procedures most of the time for painful hips because of excentration of the femoral head. When the bone maturity was acquired all hips except two (sequelae of infections) were asymptomatic with femoral heads well covered. When discovered or suspected, this disease needs of careful follow-up. When operative treatment is necessary, we think that it has to be a pelvic surgery. We performed 4 times a triple pelvic osteotomy; 3 times a Chiari osteotomy; and twice a hip shelf arthroplasty. Those operative treatments have always been done with good results in our review.

Adolescent↗
PubMed2004

Bioprosthetic mitral valve thrombosis. Importance of transesophageal echocardiography in the diagnosis and follow-up after treatment.

OBJECTIVE: To report the clinical and echocardiographic findings of bioprosthetic mitral valve thrombosis and the value of transesophageal echocardiography (TEE) in its diagnosis and monitoring of thrombolysis. METHODS: One hundred and eleven patients with mitral bioprostheses underwent TEE, and 4 out of 7 suspected of having a thrombus on these prostheses were included in the study (mean age = 60.2+/-10.2 years; 2 men). The diagnosis was confirmed with serial TEE and clinical evolution. The morphologic features of the prosthetic leaflets, as well as the presence and characteristics of attached echogenic masses were investigated. The mean gradient through the prosthesis and the valvular area were obtained. RESULTS: The diagnosis of bioprosthetic mitral valve thrombosis was established 48.7+/-55.2 months after surgery. Two patients had ischemic stroke in the early postoperative period. The mean overall gradient was high (11.4+/-3 mmHg) and the valvular area reduced (1.24+/-0.3 cm2). On TEE, echogenic masses on the left ventricular face of the mitral bioprosthesis suggestive of thrombus were evidenced in all patients. On serial TEE (136+/-233 days), in 2 patients the thrombus had disappeared and in 2 others it was smaller after treatment, the mean gradient dropped to 6.2+/-3 mmHg (P = 0.004; 95% CI), and the valvular area increased to 2.07+/-0.4 (P = NS). CONCLUSION: TEE proved to be useful for detecting bioprosthetic mitral valve thrombosis and was effective in monitoring the treatment in all patients.

Aged↗
PubMed1992

[MRI of malformative syringomyelia. Descriptive and developmental aspect].

132 cases of malformative syringomyelia have been studied at the C.I.E.R.M. (Interdepartmental Magnetic Resonance Center) of Bicêtre Hospital. The authors describe their technique for the exploration on the cord in case of suspected intramedullary cavitation, and emphasize the morphological and evolutive aspects of these abnormalities, whether they have been operated or not.

Adolescent↗
PubMedDate not supplied

[Symmetries and homologies of Geomerida].

The symmetry of Earths life cover (Geomerida) was described generally by L.A. Zenkevich (1948). It coincides with the symmetry of geographic cover. Its symmetry elements are equatorial plane and three meridonal planes corresponded to oceans and continents. The hypsographic curve with point of inflection (symmetry element) on 3 km depth line should be added to these elements. The plankton and benthos communities as well as fauna of taxons are distributed symmetrically according these symmetry elements. Zenkevich model was successfully extrapolated to plankton by K.V. Beklemishev (1967, 1969) and to abyssal benthos by Sokolova M.N. (1986). The plankton communities inhabiting symmetrically located macrocirculations are considered as homologous. The character of circulation determines the trophic structure of plankton and benthos. In the case of high productivity of plankton, benthic grazing animals feed on sedimented particles have bilateral symmetric mouthpart. Otherwise they have to acquire food from water column and use cyclomeric mouthpart. Thus, the symmetry of macrocirculations determines the symmetry distribution of benthic animals with two major symmetries of mouthparts. The peculiarities of organisms' symmetry are discussed in the context of Pierre Curie principle and the ideas of K.V. Beklemishev concerning evolution of morphological axes.

Animals↗
PubMed1991

[Neuroendocrine tumors of the mammary gland. Current evaluation apropos of a case].

The authors report a case of infiltrating non-mucinous neuroendocrine breast tumor of both nesidioid and carcinoid type, exclusively composed of argyrophil cells and showing estrogen receptors. By comparing it to those published in literature, they conclude that there are two types of breast tumors with argyrophil cells: one very rare, exclusively composed of neuroendocrine cells, which may present all of the morphological, functional, evolutive aspects and particularly the carcinoid pattern of diffuse endocrine system tumors; the other is more common, composite, reminiscent according to the abundance of their neuroendocrine components, either of the features of diffuse endocrine system tumors, or of those of conventional adenocarcinomas. Their findings help to explain that the combined hormonoreceptive and hormonosecreting nature of these tumors is the particular property of their neuroendocrine cells comparable to that of the pituitary gland. In the composite tumors, these cells are associated in symbiosis with the epithelial glandular cells which are of ectodermal origin. Such an association, also observed in other parts of the body, is not fortuitous but functional and thus could contra-indicate antiestrogen hormonetherapy.

Aged↗
PubMed1991

Genetic events in breast cancer and their clinical correlates.

The great heterogeneity of clinical breast cancer probably reflects heterogeneity of the mechanisms that are involved in its genesis and in disease progression. Genetic events that may be critical for tumor etiology, may determine tumor characteristics, and may contribute to tumor evolution should differ among individuals and among individual tumors and may distinguish subgroups with varying prognoses. We approach this problem from two viewpoints: one is based on population studies and the other on genetic events at the cellular level. 1. Population-based questions: What susceptibility factors are associated with individuals and groups who develop tumors? Inheritance patterns, familial aggregates, and associations with other tumors and other genetic diseases have been described for breast cancer. Bilateral and multifocal tumors may be examples of inherited predisposition, and their clinical and biological characteristics should be informative. Are there associations with tumor identifiers, such as histologic type and other tumor markers, for any of the "increased susceptibility" states? 2. Tumor-derived information: What types and frequencies of genetic alterations are found; do they relate to stage of tumor evolution, to morphologic classification, or to clinical evidence of comparative malignancy? Genetic evaluation depends upon cytogenetic and cytometric methods at the cellular level, and on detection of mutation, gene deletion, or amplification at the molecular level. We examine whether observed genetic alterations suggest mechanistic bases for morphologic distinctions among breast cancers and whether they assist in defining clinical phenotypes or steps in tumor progression. The general conclusions are that breast cancer comprises a complex set of neoplasms, that there is as yet little evidence to favor a final common pathway for its origin, and that a wide range of biological perturbations underlie its clinical course in the individual patient. An understanding of the basic mechanisms, their variety, and which of them apply in individual cases, is necessary as a rational basis for classification and for the development of strategies to interfere with tumor development in high-risk individuals.

Breast Neoplasms↗
PubMedDate not supplied

[Modern approach to the classification and diagnosis of pneumonia].

New classification of pneumonia is pragmatic since a significant criterion is a condition in which an infection may develop: inflammations of the lungs in the home environment, immunodeficient patients, hospital infections, as a result of iatrogen complication, epidemics, etc. The principle of etiologic differentiation is reasonable when the therapy is indicated with certainty. Due to the difficulties in isolation and identification of sputum as well as the disappearance of the agent on onset of treatment because of specific therapy, the pathogenetic evolution and morphologic definition of the process is of great importance in the diagnostics and classification of pneumonia. In most patients the pneumonia has a clear course and the diagnosis is mostly established either by epidemiologic and clinical finding, laboratory testing and radiographically or by the response on empiric therapy. In some cases the invasive methods of diagnostics should be applied (BAL, transtracheal biopsy) in order to avoid false positive findings from the upper respiratory tract.

Humans↗
PubMed1990

[The association of neuro-endocrine carcinoma of the skin and Bowen's disease. Review of the literature apropos of 4 cases].

Four cases of neuroendocrine carcinoma following Bowen's disease are presented. An immunohistochemical study was performed. The four patients, 3 men and a woman, ranging from seventy to eighty-seven years of age, developed a nodular tumor on a preexisting cutaneous lesion. In one of those cases the diagnosis of Bowen's disease was confirmed histologically before the apparition of the nodular tumor. The tumors were localized on the scalp, thorax, dorsum of the hand, and the scrotum. The four tumors were immunohistologically typical of neuro-endocrine carcinoma: there was a positivity for neurofilaments, cytokeratins and neurone-specific enolase. The clinico-pathological characteristics of those 4 neuro-endocrine carcinomas associated with a Bowen's disease, when compared with the 15 similar described in the literature, are identical to the isolated neuroendocrine carcinoma, from a clinical, morphological and evolutional point of view. The majority are seen in patients older than 60 years old and one third of the cases described survived at least 5 years. The coexistence of Bowen's disease and neuroendocrine carcinoma, the association of neuroendocrine and epidermoid cells in other cutaneous tumors, reactivate the controversy concerning the histogenesis of the so-called Merkel cell carcinoma. In fact, the histogenesis of the tumor is still not fully understood.

Aged↗
PubMed1990

[Morphofunctional changes in potential liver allografts in experimental conditions].

As a part of morphofunctional investigations of validations cadaveric grafts for transplantation evolution of the histomorphological changes was followed by the experiments on guinea pigs. Liver samples were immediately after sacrificing the animals and 1, 2, and 4h later and kept at body temperature, which corresponded to the conditions of "warm ischemia". Second group of samples was immerged in Saline are +4 degrees C (hibernation-preservation) and was taken for analysis in same intervals as previous ones. Evolution of morphological and enzymatic changes was evident in short interval after sacrificing the animals. First changes were observed in cytoplasm and then in nuclei and interestitum. Changes of hepatic cells from hibernation preservation group were significant damaged comparing with the corresponding samples obtained from cadaver. ("warm ischemia"). These preliminary results indicated that length of liver graft preservation is very limited. Furthermore, this results demand for the future investigations in different conditions of preservation.

Animals↗