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1.
ABO, Rh and MN blood groups were studied among the people of Ahwaz, Khuzistan, Iran. The people of Ahwaz are characterized by high frequencies of the blood groups 0 (41.16%), Rh-positive (90.0%) and MN (48.13%). These frequencies are significantly different from those obtained in other Iranian populations, which is caused by the co-operation of various factors.  相似文献   
2.
234 218 births (1975-1983) from a hospital in Tehran have been analysed for seasonality of birth and sex ratio. The results show more births in winter and less births in fall. The sex ratio is higher in summer and lower in fall. The occurrence of multibirths shows higher twinning and triplet rates in spring and fall, respectively, whereas lower twinning and triplet rates occur in winter and summer, respectively. It could be demonstrated that geographical factors influence the rates of births and multibirths as well as the sex ratio.  相似文献   
3.
Black microcolonial fungi (MCF) and black yeasts are among the most stress-resistant eukaryotic organisms known on Earth. They mainly inhabit bare rock surfaces in hot and cold deserts of all regions of the Earth, but some of them have a close phylogenetic relation to human pathogenic black fungi which makes them important model organisms also with respect to clinical mycology. The environment of those fungi is especially characterized by extreme changes from humidity to long periods of desiccation and extreme temperature differences. A key to the understanding of MCF ecology is the question about metabolic activity versus dormancy in the natural environments. In this study, the time lag from the desiccated state to rehydration and full metabolic activity and growth was measured and defined in accordance with simulated environmental conditions. The ability to survive after desiccation and the speed of rehydration as well as changes of the whole cell protein pattern are demonstrated. Whereas both mesophilic strains—Exophiala jeanselmei and Knufia perforans (=Coniosporium perforans)—show a clear reaction toward desiccation by production of small proteins, Cryomyces antarcticus—the extremotolerant MCF—does not show any response to desiccation but seems just to down-regulate its metabolism. Data on intracellular sugar suggest that both trehalose and mannitol might play a cell protective role in those fungi.  相似文献   
4.

Background and Objectives

Desmoplastic melanoma is a unique subtype of melanoma which typically affects older patients who often have comorbidities that can adversely affect survival. We sought to identify melanoma-specific factors influencing survival in patients with desmoplastic melanoma.

Methods

Retrospective review from 1993 to 2011 identified 316 patients with primary desmoplastic melanoma. Clinicopathologic characteristics were correlated with nodal status and outcome.

Results

Fifty-five patients (17.4%) had nodal disease: 33 had a positive sentinel lymph node biopsy and 22 developed nodal recurrences (no sentinel lymph node biopsy or false-negative sentinel lymph node biopsy). Nodal disease occurred more often in younger patients and in cases with mixed compared with pure histology (26.7% vs. 14.6%); both of these variables significantly predicted nodal status on multivariable analysis (p<0.05). After a median follow-up of 5.3 years, recurrence developed in 87 patients (27.5%), and 111 deaths occurred. The cause of death was known in 79 cases, with 47 deaths (59.5%) being melanoma-related. On multivariable analysis, Breslow thickness, mitotic rate ≥1/mm2 and nodal status significantly predicted melanoma-specific survival (p<0.05).

Conclusions

Nodal status predicts melanoma-specific survival in patients with desmoplastic melanoma. However, since patients with desmoplastic melanoma represent an older population, and a considerable proportion of deaths are not melanoma-related (40.5%), comorbidities should be carefully considered in making staging and treatment decisions in this population.  相似文献   
5.
Rock inhabiting fungi are among the most stress tolerant organisms on Earth. They are able to cope with different stressors determined by the typical conditions of bare rocks in hot and cold extreme environments. In this study first results of a system biological approach based on two-dimensional protein profiles are presented. Protein patterns of extremotolerant black fungi – Coniosporium perforans, Exophiala jeanselmei – and of the extremophilic fungus – Friedmanniomyces endolithicus – were compared with the cosmopolitan and mesophilic hyphomycete Penicillium chrysogenum in order to follow and determine changes in the expression pattern under different temperatures. The 2D protein gels indicated a temperature dependent qualitative change in all the tested strains. Whereas the reference strain P. chrysogenum expressed the highest number of proteins at 40 °C, thus exhibiting real signs of temperature induced reaction, black fungi, when exposed to temperatures far above their growth optimum, decreased the number of proteins indicating a down-regulation of their metabolism. Temperature of 1 °C led to an increased number of proteins in all of the analysed strains, with the exception of P. chrysogenum. These first results on temperature dependent reactions in rock inhabiting black fungi indicate a rather different strategy to cope with non-optimal temperature than in the mesophilic hyphomycete P. chrysogenum.  相似文献   
6.
Pancreatic amyloid is found in patients with insulinomas and type 2 diabetes. To study mechanisms of islet amyloidogenesis, we produced transgenic mice expressing the unique component of human islet amyloid, human islet amyloid polypeptide (hIAPP). These mice develop islet amyloid after 12 mo of high-fat feeding. To determine whether we could accelerate the rate of islet amyloid formation, we crossbred our hIAPP transgenic animals with RIP-Tag mice that develop islet tumors and die at 12 wk of age from hypoglycemia. At 12 wk of age, this new line of hIAPPxRIP-Tag mice was heavier (29.7 +/- 1.0 vs. 25.0 +/- 1.3 g, P < 0.05) and had increased plasma glucose levels (4.6 +/- 0.4 vs. 2.9 +/- 0.6 mmol/l, P < 0.05) compared with littermate RIP-Tag mice. However, the hIAPPxRIP-Tag mice did not display islet amyloid or amyloid fibrils despite high circulating hIAPP levels (24.6 +/- 7.0 pmol/l). Interestingly, hIAPPxRIP-Tag mice had a longer life span than RIP-Tag mice (121 +/- 8 vs. 102 +/- 5 days, P < 0.05). This increase in life span in hIAPPxRIP-Tag was positively correlated with body weight (r = 0.48, P < 0.05) and was associated with decreased insulin sensitivity compared with RIP-Tag mice. hIAPPxRIP-Tag mice did not develop amyloid during their 4-mo life span, suggesting that increased hIAPP secretion is insufficient for islet amyloid formation within such a short time. However, hIAPPxRIP-Tag mice did have an increase in life span that was associated with insulin resistance, suggesting that hIAPP has extrapancreatic effects, possibly on peripheral glucose metabolism.  相似文献   
7.
The need for standardized experimental conditions to gain relevant and reproducible results has increased the demand for well characterized continuously growing cell lines that exhibit the characteristics of their normal counterparts. Immortalization of normal human cells by ectopic expression of the catalytic subunit of human telomerase (hTERT) has shown to result in highly differentiated cell lines. However, the influence of the increased telomerase activity on the protein expression profile was not investigated so far. Therefore, we have immortalized human umbilical vein endothelial cells (HUVECs) by hTERT overexpression and compared them to their normal early passage and senescent counterparts. This study, including a proteomic approach, shows that ectopic hTERT expression leads to a stable growing cell line. Although these cells are highly differentiated, the protein expression profile of the cell line is different to that of normal early passage and senescent cells.  相似文献   
8.
Regular consumption of fruits has a positive influence on human health by disease prevention. However parallel to dietetic benefits, IgE-mediated fruit allergies have been shown to be an increasing health risk for children and adults in the Northern hemisphere. The spectrum of food allergies ranges from chronic symptoms to more acute problems and even anaphylaxis. Fruit proteins with high primary sequence similarity display also homologous tertiary structures, resulting in similar epitopes to IgEs and consequently in cross-reactivity. In this review we present the major allergens of stone and pome fruits and discuss the presence of homologous proteins in small fruits. Interestingly these proteins, which might pose an allergenic potential for pre-sensitised individuals are expressed also in strawberry, raspberry and blueberry, otherwise rich in beneficial biofactors.  相似文献   
9.
The Acp2 gene encodes the beta subunit of lysosomal acid phosphatase, which is an isoenzyme that hydrolyzes orthophosphoric monoesters. In mice, a spontaneous mutation in Acp2 results in severe cerebellar defects. These include a reduced size, abnormal lobulation, and an apparent anterior cerebellar disorder with an absent or hypoplastic vermis. Based on differential gene expression in the cerebellum, the mouse cerebellar cortex can normally be compartmentalized anteroposteriorly into four transverse zones and mediolaterally into parasagittal stripes. In this study, immunohistochemistry was performed using various Purkinje cell compartmentation markers to examine their expression patterns in the Acp2 mutant. Despite the abnormal lobulation and anterior cerebellar defects, zebrin II and PLCβ4 showed similar expression patterns in the nax mutant and wild type cerebellum. However, fewer stripes were found in the anterior zone of the nax mutant, which could be due to a lack of Purkinje cells or altered expression of the stripe markers. HSP25 expression was uniform in the central zone of the nax mutant cerebellum at around postnatal day (P) 18–19, suggesting that HSP25 immunonegative Purkinje cells are absent or delayed in stripe pattern expression compared to the wild type. HSP25 expression became heterogeneous around P22–23, with twice the number of parasagittal stripes in the nax mutant compared to the wild type. Aside from reduced size and cortical disorganization, both the posterior zone and nodular zone in the nax mutant appeared less abnormal than the rest of the cerebellum. From these results, it is evident that the anterior zone of the nax mutant cerebellum is the most severely affected, and this extends beyond the primary fissure into the rostral central zone/vermis. This suggests that ACP2 has critical roles in the development of the anterior cerebellum and it may regulate anterior and central zone compartmentation.  相似文献   
10.

Microglia are the immune cells of the central nervous system involved in a variety of developmental processes, such as regulation of cell death and survival, spatial patterning, and contribute to the development of Purkinje cells (PCs) during migration. Microglia express immunoglobulin G Fc receptors (FcgRs). In this report, we describe microglial FcgR expression and its relation to abnormal PC migration in the cerebellum during development. To detect microglial FcgR, the direct anti-IgG (secondary antisera) and high concentrations of Triton X-100 were applied as a method for labeling microglial cells without the use of any specific primary antiserum. By using Acp2?/? mice, which show an excessive PC migration into the molecular layer (ml), and 3 different types of mice with a null to alter the Reelin pathway (Reeler-, Dab1 (SCM)-, and Apoer mutant mice), we studied the location of PCs and the expression of FcgRs. Wild type littermates were used as controls in all studies. We show that the expression of microglial FcgRs was absent and PCs were ectopically located in the white matter in the cerebella of all mutant mice, except for the Acp2?/? mice (PCs were located in the ml). These results suggest a role for FcgRs in the Reelin signaling pathway, not in regulating PC migration, but rather in the adaptation to an environment with a relatively large number of ectopically located PCs. However, the exact correlation between the ectopic location of PCs and lack of FcgRs in Reeler, SCM, and Apoer?/? mice and the presence of FcgRs and directed PC location in the ml in Acp2?/? mice are yet to be determined.

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