Allelic imbalance studies of chromosome 9 suggest major differences in chromosomal instability among nonmelanoma skin carcinomas

CONTEXTO: Vários estudos de perda de heterozigozidade na região 9p21-p22, que abriga os genes supressores tumorais CDKN2a/p16INK4a, p19ARF e p15INK4b, têm sido realizados em uma ampla série de tumores humanos, incluindo os melanomas familiares. Perdas e ganhos em outras regiões do cromossomo 9 também têm sido observados com freqüência e podem indicar mecanismos adicionais no processo de tumorigênese dos carcinomas basocelulares da pele. OBJETIVO: Investigar o equilíbrio alélico existente na região 9p21-p22 em carcinomas basocelulares. TIPO DE ESTUDO: Análise molecular de marcadores de microssatélites em tumores e controles. LOCAL: Dois serviços de dermatologia de atendimento terciário em universidades públicas de São Paulo e o Laboratório de Genética Molecular do Câncer da Universidade Estadual de Campinas (UNICAMP), Brasil. PARTICIPANTES: Examinamos 13 casos benignos, incluindo 4 queratoses solares, 3 queratoacantomas, 3 nevos melanocíticos, 2 doenças de Bowen e 1 neurofibroma cutâneo, além de 58 tumores malignos da pele: 14 de células escamosas, 40 carcinomas basocelulares e 4 melanomas; em pacientes consecutivamente encaminhados à clínica de Dermatologia da Unicamp e que concordaram em participar do estudo. VARIÁVEIS ESTUDADAS: O tumor principal e uma porção normal de pele não-adjacente foram removidos cirurgicamente de pacientes que consecutivamente procuraram os ambulatórios de dermatologia da Universidade Estadual de Campinas (UNICAMP) e da Universidade Estadual de São Paulo (Unesp), São Paulo, por causa de lesões cutâneas. Extraímos DNA tanto de tecido tumoral como do correspondente tecido normal de cada paciente. Para amplificar regiões de repetição polimórfica de microssatélites do cromossomo 9, foram utilizados quatro pares de primers, sendo dois deles destinados à região 9p21-p22. RESULTADOS: Identificamos oito casos (20%) de desequilíbrio alélico entre os carcinomas basocelulares, sendo dois casos de perda de heterozigozidade e seis casos de instabilidade de microssatélite na região 9p21-p22. Outros marcadores também mostravam anormalidades em três destes tumores, enquanto nenhuma alteração foi detectada entre os casos benignos e nos outros tumores malignos. CONCLUSÃO: Esta dependência fenotípica sugere que existem diferenças importantes no comportamento das formas mais comuns de tumores cutâneos não-melanocíticos em relação à sua tendência para instabilidade de microssatélite no cromossomo 9. Considerando-se que os genes CDKN2a/p16INK4a, p19ARF e p15INK4b não parecem responsáveis pelas anormalidades observadas, outros genes em 9p21-p22 podem estar envolvidos na etiopatogenia e na progressão dos carcinomas basocelulares.

SEX-RELATED DIFFERENCES IN THE ANALGESIC RESPONSE TO THE RAT TAIL IMMERSION TEST

The analgesic response was evaluated by the tail immersion test in adult male (N = 30), female (N = 21) and androgenized female Wistar rats (N = 15). The reaction time for tail withdrawal from the hot water bath was faster for male than for female rats (3.48 +/- 0.12 vs 6.46 +/- 0.42 s). The reaction time of androgenized female rats was similar to that of male rats (3.08 +/- 0.16 s). Blockade of opiate receptors with naloxone (2 mg/kg, ip) decreased the sensitivity to the noxious stimuli in males (4.08 +/- 0.10 s) and in androgenized females (3.69 +/- 0.19 s) but increased it in female rats (5.01 +/- 0.41 s). These data show sex-related differences in the analgesic response evaluated by the tail immersion test and indicate that administration of androgens to newborn female rats affects their pain sensitivity.

Differences in reactivity of paracoccidioidomycosis sera with gp43 isoforms

The glycoprotein gp43 from Paracoccidioides brasiliensis is the main antigenic component in paracoccidioidomycosis (PCM) because it is recognized by 100% of PCM patients. It has also been shown that different fungal strains produce gp43 with at least four isoform profiles. In this study, different isoform profiles from gp43, with pIs ranging from 5.8 to 8.5, were affinity purified from various P. brasiliensis (B-339, S.S., 1925 and I-9) exoantigens. Because of the isoform heterogeneity, we questioned whether those isoform profiles could be similarly recognized by acute or chronic PCM patients. By using a specific and sensitive method for detection of human IgG anti-gp43 antibodies, the monoclonal antibody capture immunoassay, we report that not all gp43 isoform profiles are equally recognized in PCM sera when anti-gp43 MAb 17c was employed as capturing antibody. Our result showed that recognition of pI 8.5 gp43 isoform was significantly lower for both acute (56%) and chronic patients (71%), compared with gp43 isoforms from the standard strain B-339. on the other hand, when anti-gp43 MAb 8a, which recognizes a different antigenic epitope was used to capture the different gp43 isoform profiles, all patient's sera reacted similarly. The results described suggest that not all the antigenic epitopes expressed by gp43 are equally present in all P. brasiliensis strains.

Correlations between differences in amino-terminal sequences and different hemolytic activity of sticholysins

Sticholysins I and II (St I and St II) are cytolysins produced by the sea anemone Stichodactyla helianthus. In spite of their 93% sequence homology, St II is more hemolytic against human erythrocytes than St 1. In order to establish the possible causes of this difference, we studied the hemolytic activity of synthetic peptides containing sequences from the N-termini of both proteins. The results demonstrated that the differences in hemolytic activity of the toxins could be ascribed at least partly to differences in their N-termini. (c) 2007 Elsevier Ltd. All rights reserved.

Measurement of phase differences between the diffracted orders of deep relief gratings

Measurement of the phase difference between the 0th and the 1st transmitted diffraction orders of a symmetrical surface-relief grating recorded on a photoresist film is carried out by replacement of the grating in the same setup with which it was recorded. The measurement does not depend on lateral shifts of the replaced grating relative to the interference pattern, on environmental phase perturbations or on the wave-front quality of the interfering beams. The experimental data agree rather well with theoretical results calculated for sinusoidal profiled gratings. (C) 2003 Optical Society of America.

Factors contributing to the differences in peritonitis rates between centers and regions

Despite improvements in connectology, peritoneal dialysis (PD) - associated peritonitis contributes significantly to morbidity and modality failure in patients maintained on PD therapy. A broad spectrum of organisms -gram-positive, gram-negative, fungal, anaerobic - are involved in this complication. In addition, a significant percentage of episodes involve polymicrobial and culture-negative infection. Technological advances are being developed to minimize the incidence of access-related complications such as peritonitis. Many traditional factors such as exit-site infection and poor technique have been already identified. In the present review, we discuss the geographic, patient selection, and clinical issues that can affect peritonitis rates in different areas of the world and in different centers in the same area.

Relativistic deformed mean-field calculation of binding energy differences of mirror nuclei

Binding energy differences of mirror nuclei for A = 15, 17, 27, 29, 31, 33, 39 and 41 are calculated in the framework of relativistic deformed mean-field theory. To fully include the effects of the polarization of the nuclear core due to the extra particle or hole, the spatial components of the vector meson fields and the photon are taken into account in a self-consistent manner. The calculated binding energy differences are systematically smaller than the experimental values and lend support to the existency of the Okamoto-Nolen-Schiffer anomaly found decades ago in nonrelativistic calculations, For the majority of the nuclei studied, however, the results are such that the anomaly is significantly smaller than the one obtained within state-of-the-art nonrelativistic calculations.

Differences and similarities in the pore size distribution of soybean seed coats

In this work we apply the mercury porosimetry technique to determine the pore size distribution in soybean seed coats of different varieties. The analyses show that the porosity of soybean seed coats is different when seeds of different genotypes are compared. This result points the possibility of using pore size distribution to varietal discrimination.

SEX-RELATED DIFFERENCES IN CARDIOVASCULAR-RESPONSES TO COMMON CAROTID OCCLUSION IN CONSCIOUS RATS

Mean arterial pressure and heart rate were determined in conscious, unrestrained groups of 10 male, female and androgenized female Wistar rats 20 s (early pressor response) and 1 min (late sustained response) after bilateral carotid artery occlusion. The early pressor response, which is of carotid reflex origin, was 40% greater in female than in male rats (45 +/- 2 vs 63 +/- 3 mmHg, respectively). The late sustained response, which is of central origin (probably ischemic), did not differ between male and female rats (32 +/- 2 vs 37 +/- 4 mmHg, respectively). The magnitude of the early pressor response of androgenized female tats (50 +/- 2 mmHg) was similar to that of male rats (45 +/- 2 mmHg) but the late sustained response was 19% smaller (26 +/- 2 mmHg). Common carotid occlusion caused increases in heart rate which were greater in female (51 +/- 9 and 34 +/- 9 beats/min in the early pressor response and late sustained response, respectively) than in male rats (31 +/- 5 and 8 +/- 4 beats/min, respectively). In androgenized female rats, heart rate decreased during common carotid occlusion (34 +/- 7 and 35 +/- 8 beats/min after 20 s and 1 min, respectively). These data provide evidence that there are substantial sex-related differences in the cardiovascular responses to common carotid occlusion in conscious rats and indicate that administration of androgens to newborn female rats affects the baroreceptor reflex control of their arterial pressure.

Scent-marking behaviour in free-ranging golden-faced saki monkeys, Pithecia pithecia chrysocephala: Sex differences and context

Scent-marking behaviour of golden-faced saki monkey, Pithecia pithecia chrysocephala, was observed intermittently between 1987 and 1990 for a family group in a Central Amazonian forest fragment. of 95 scent-marking events (during 275.5 hours of observation), throat-and-chest rubbing accounted for all except one anogenital rubbing. Nine of the throat-and-chest markings also involved touching groin with hands and eight markings (including the anogenital), urinating on the marked branch. Marking behaviour is strongly sex related, with the adult male making 88.4% of the markings. Scent-marking frequency by the adult male increased during breeding periods. Scent-marking behaviour seems related to courtship, and possibly stimulates sexual behaviour. All regularly marked spots consisted of horizontal branches on commonly travelled routes. Eleven occurred in feeding trees and lianas, but none in sleeping trees. Scent-marking behaviour in the monkeys studied here was not related to intergroup encounters and probably did not have a territorial function, although it may do so where different groups interact.

Morphological caste differences and non-sterility of workers in Brachygastra augusti (Hymenoptera, Vespidae, Epiponini), a neotropical swarm-founding wasp

Morphological caste differences and ovary conditions were analyzed in four colonies of Brachygastra augusti collected in different stages of the colony cycle. Differences between castes are distinct suggesting pre-imaginal determination. Many intermediates (non-inseminated ovary-developed females) were found. Because these intermediate females were morphologically similar to workers, it is suggested that they are young ovary-developed workers. Because there is a more evident overlap between queens and workers in the colony in pre-emergence of workers stage, and in three colonies in latter stages, especially in worker-production colonies, it is suggested that smaller queens are probably less viable than larger queens as observed in previously studied epiponines.