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The primate adolescent period is characterized by a series of changes in physiology, behavior, and social relationships. Orangutans have the slowest life history and the longest period of dependency of all primates. As members of a semisolitary species with high levels of sexual coercion, adolescent female orangutans face a unique combination of challenges when achieving independence from their mother. This study examined the mating behavior of adolescent female orangutans and compared it with that of adult females to assess whether mating behavior reflects distinct strategies at these different points in the life cycle. Data were collected in Gunung Palung National Park on the island of Borneo over 20 years. Mating events from adolescent (n = 19) and adult females (n = 26) were scored and compared. Adolescent female mating events had significantly higher mating scores (indicating more proceptivity) than those of adult females (β = 1.948, p = .001). Adolescent females also engaged in elaborate sociosexual interactions with different flanged males, behaviors that were never observed during mating events of adult females. These interactions involved characteristic behavior on the part of both the adolescent females and the flanged males. Given these findings and the documentation of similar accounts of adolescent female–flanged male mating from the island of Sumatra, we propose that adolescent female orangutans display distinctive behavioral repertoires throughout the genus Pongo which serves to overcome male ambivalence toward nulliparous females, establish familiarity, and evaluate coercive tendencies in flanged males. We suggest that these behavioral patterns are an integral part of female social development in a female philopatric, but highly dispersed species where consistent social support is absent after ranging independence is achieved.  相似文献   
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To explore the physiological significance of N‐glycan maturation in the plant Golgi apparatus, gnt1, a mutant with loss of N‐acetylglucosaminyltransferase I (GnTI) function, was isolated in Oryza sativa. gnt1 exhibited complete inhibition of N‐glycan maturation and accumulated high‐mannose N‐glycans. Phenotypic analyses revealed that gnt1 shows defective post‐seedling development and incomplete cell wall biosynthesis, leading to symptoms such as failure in tiller formation, brittle leaves, reduced cell wall thickness, and decreased cellulose content. The developmental defects of gnt1 ultimately resulted in early lethality without transition to the reproductive stage. However, callus induced from gnt1 seeds could be maintained for periods, although it exhibited a low proliferation rate, small size, and hypersensitivity to salt stress. Shoot regeneration and dark‐induced leaf senescence assays indicated that the loss of GnTI function results in reduced sensitivity to cytokinin in rice. Reduced expression of A‐type O. sativa response regulators that are rapidly induced by cytokinins in gnt1 confirmed that cytokinin signaling is impaired in the mutant. These results strongly support the proposed involvement of N‐glycan maturation in transport as well as in the function of membrane proteins that are synthesized via the endomembrane system.  相似文献   
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Currently, in many hospitals in Indonesia, the Occupation Safety and Health Committee in the Hospital (OSH-CH) is evenly distributed. It is based on the instruction of the Health Department of the Republic of Indonesia that obliges each hospital to establish the committee the main function of which is to prepare necessary equipment for risk management essential in the hospital. OSH-CH must also be responsible for upgrading the accreditation process of the hospital as to work units on occupational safety, fire control and disaster preparedness. However, in fact, OSH-CH has insignificant power as many people, especially the manager of the hospital, may expect. OSH-CH tends to be stagnant and irresponsive. In other words, it tends to be non-professional. The reasons are: (1) the staff of OSH-CH work as part-timers, (2) they have minimum understanding about OSH, (3) they do not have incentive and enough budget, (4) it is only to show that the hospital "obeys" the orders of the authorities, (5) managerial support within the hospital is minimal, and (6) there are no significant cases of work-related accidents and illnesses. These explain the reasons why OSH-CH has no significant power and the progress of its program is so slow. For some large hospitals this often leads to inefficiency and ineffectiveness of the organization, and in some cases it may even tend to create difficulties in conducting risk control. Based on these reasons, it is recommended to establish an autonomous OSH work unit that operates on the basis of structural and formal organizational operations. The paper aims to discuss the proposed concept of the autonomous OSH work unit established in hospitals, particularly for large hospitals. It is urgent to develop long-term capacities of the unit to sustain its reliability.  相似文献   
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Background

Historically, the main focus of studies of childhood mortality has been the infant and under-five mortality rates. Neonatal mortality (deaths <28 days of age) has received limited attention, although such deaths account for about 41% of all child deaths. To better assess progress, we developed annual estimates for neonatal mortality rates (NMRs) and neonatal deaths for 193 countries for the period 1990–2009 with forecasts into the future.

Methods and Findings

We compiled a database of mortality in neonates and children (<5 years) comprising 3,551 country-years of information. Reliable civil registration data from 1990 to 2009 were available for 38 countries. A statistical model was developed to estimate NMRs for the remaining 155 countries, 17 of which had no national data. Country consultation was undertaken to identify data inputs and review estimates. In 2009, an estimated 3.3 million babies died in the first month of life—compared with 4.6 million neonatal deaths in 1990—and more than half of all neonatal deaths occurred in five countries of the world (44% of global livebirths): India 27.8% (19.6% of global livebirths), Nigeria 7.2% (4.5%), Pakistan 6.9% (4.0%), China 6.4% (13.4%), and Democratic Republic of the Congo 4.6% (2.1%). Between 1990 and 2009, the global NMR declined by 28% from 33.2 deaths per 1,000 livebirths to 23.9. The proportion of child deaths that are in the neonatal period increased in all regions of the world, and globally is now 41%. While NMRs were halved in some regions of the world, Africa''s NMR only dropped 17.6% (43.6 to 35.9).

Conclusions

Neonatal mortality has declined in all world regions. Progress has been slowest in the regions with high NMRs. Global health programs need to address neonatal deaths more effectively if Millennium Development Goal 4 (two-thirds reduction in child mortality) is to be achieved. Please see later in the article for the Editors'' Summary  相似文献   
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Coronavirus envelope (E) proteins are short (~100 residues) polypeptides that contain at least one transmembrane (TM) domain and a cluster of 2-3 juxtamembrane cysteines. These proteins are involved in viral morphogenesis and tropism, and their absence leads in some cases to aberrant virions, or to viral attenuation. In common to other viroporins, coronavirus envelope proteins increase membrane permeability to ions. Although an NMR-based model for the TM domain of the E protein in the severe acute respiratory syndrome virus (SARS-CoV E) has been reported, structural data and biophysical studies of full length E proteins are not available because efficient expression and purification methods for these proteins are lacking. Herein we have used a novel fusion protein consisting of a modified β-barrel to purify both wild type and cysteine-less mutants of two representatives of coronavirus E proteins: the shortest (76 residues), from SARS-CoV E, and one of the longest (109 residues), from the infectious bronchitis virus (IBV E). The fusion construct was subsequently cleaved with cyanogen bromide and all polypeptides were obtained with high purity. This is an approach that can be used in other difficult hydrophobic peptides.  相似文献   
8.
Nasopharyngeal carcinoma (NPC) is a malignant tumor in the nasopharyngeal epithelial cells that caused by many factors, one of which is the viral infection of EBV (Epstein Barr Virus). The standard treatments to cure NPC still have not been encouraging. The prevention through vaccination is an effective way to stop the disease. However, EBV vaccine being able to cover all variants of virus is still not available yet. Therefore, we identified the conserved region of glycoprotein 350/220 of EBV which has immunogenic and antigenic properties. The glycoprotein 350/220 is viral surface protein responsible to bind CR2 receptor, mediated EBV to enter the host cell. The conserved domain is crucial for EBV in infecting host cells. Further, by blocking CR2 binding domain of gp350/220 using antibody will inhibit EBV's spreading, and provoke an immune system to eliminate the virus in a patient. Glycoprotein 350/220 from all variants of Epstein-Barr virus was retrieved from NCBI. The conserved domain of gp350/220 was identified by aligning the protein sequences and structures. The polymorphic structure was used as a template for docking analysis to identify the resemblance of amino acid from polymorphic variants of gp350/220 that binds CR2. The epitope mapping of gp350/220 was done by Discotope BepiPred method. The result revealed that the conserved region of gp350/220 was predicted to have an epitope, QNPVYLIPETVPYIKWDNC residue, and it does not have any similarities to the human's cell surface protein. Therefore, it can be used as a reference to develop vaccine to prevent NPC.  相似文献   
9.
Mortalin was over expressed in tumor cells and bind to p53 protein. This interaction was suggested to promote sequestration of p53 in the cytoplasm, thereby inhibiting its nuclear activity. The p53 is a tumor suppressor that is essential for the prevention of cancer development and loss of p53 function is one of the early events in immortalization of human cells. Therefore, abrogation p53-mortalin interaction using small molecule is guaranteed stop cancer cell grow. However study interaction of p53-mortalin, and its inhibition using small molecule is still challenging because specific site of mortalin that bind to p53, vice versa, is still debatable. This study has aims to analyze the p53-binding site of mortalin using molecular docking and to screen drug-like compounds that have potential as inhibitors of p53-mortalin interaction using virtual screening. The result showed that the lowest energy binding of p53-mortalin complex is -31.89 kcal/mol, and p53 protein bind to substrate binding domain of mortalin (THR433; VAL435; LEU436; LEU437; PRO442; ILE558; LYS555). Furthermore, the p53-binding domain of mortalin was used as receptor to screen 9000 drug-like compounds from ZINC database using molecular docking program Auto Dock Vina in PyRx 0.8 (Virtual Screening Tools). Here, we have identified three drug-like compounds that are ZINC01019934, ZINC00624418 and ZINC00664532 adequate to interrupt stability of p53-mortalin complex that warrant for anticancer agent.  相似文献   
10.
The increasing application of regenerative medicine has generated a growing demand for stem cells and their derivatives. Single‐use bioreactors offer an attractive platform for stem cell expansion owing to their scalability for large‐scale production and feasibility of meeting clinical‐grade standards. The current work evaluated the capacity of a single‐use bioreactor system (1 L working volume) for expanding Meg01 cells, a megakaryocytic (MK) progenitor cell line. Oxygen supply was provided by surface aeration to minimize foaming and orbital shaking was used to promote oxygen transfer. Oxygen transfer rates (kLa) of shaking speeds 50, 100, and 125 rpm were estimated to be 0.39, 1.12, and 10.45 h?1, respectively. Shaking speed was a critical factor for optimizing cell growth. At 50 rpm, Meg01 cells exhibited restricted growth due to insufficient mixing. A negative effect occurred when the shaking speed was increased to 125 rpm, likely caused by high hydrodynamic shear stress. The bioreactor culture achieved the highest growth profile when shaken at 100 rpm, achieving a total expansion rate up to 5.7‐fold with a total cell number of 1.2 ± 0.2 × 109 cells L?1. In addition, cells expanded using the bioreactor system could maintain their potency to differentiate following the MK lineage, as analyzed from specific surface protein and morphological similarity with the cells grown in the conventional culturing system. Our study reports the impact of operational variables such as shaking speed for growth profile and MK differentiation potential of a progenitor cell line in a single‐use bioreactor. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:362–369, 2018  相似文献   
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