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1.
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   
2.
Loss of hand function and finger dexterity are main disabilities in the upper limb after stroke. An electromyography (EMG)-driven hand robot had been developed for post-stroke rehabilitation training. The effectiveness of the hand robot assisted whole upper limb training was investigated on persons with chronic stroke (n = 10) in this work. All subjects attended a 20-session training (3–5 times/week) by using the hand robot to practice object grasp/release and arm transportation tasks. Significant motor improvements were observed in the Fugl-Meyer hand/wrist and shoulder/elbow scores (p < 0.05), and also in the Action Research Arm Test and Wolf Motor Function Test (p < 0.05). Significant reduction in spasticity of the fingers as was measured by the Modified Ashworth Score (p < 0.05). The training improved the muscle co-ordination between the antagonist muscle pair (flexor digitorum (FD) and extensor digitorum (ED)), associated with a significant reduction in the ED EMG level (p < 0.05) and a significant decrease of ED and FD co-contraction during the training (p < 0.05); the excessive muscle activities in the biceps brachii were also reduced significantly after the training (p < 0.05).  相似文献   
3.
Human and mouse granzyme (Gzm)B both induce target cell apoptosis in concert with pore-forming perforin (Pfp); however the mechanisms by which other Gzms induce non-apoptotic death remain controversial and poorly characterised. We used timelapse microscopy to document, quantitatively and in real time, the death of target cells exposed to primary natural killer (NK) cells from mice deficient in key Gzms. We found that in the vast majority of cases, NK cells from wild-type mice induced classic apoptosis. However, NK cells from syngeneic Gzm B-deficient mice induced a novel form of cell death characterised by slower kinetics and a pronounced, writhing, ‘worm-like'' morphology. Dying cells initially contracted but did not undergo membrane blebbing, and annexin-V staining was delayed until the onset of secondary necrosis. As it is different from any cell death process previously reported, we tentatively termed this cell death ‘athetosis''. Two independent lines of evidence showed this alternate form of death was due to Gzm A: first, cell death was revealed in the absence of Gzm B, but was completely lost when the NK cells were deficient in both Gzm A and B; second, the athetotic morphology was precisely reproduced when recombinant mouse Gzm A was delivered by an otherwise innocuous dose of recombinant Pfp. Gzm A-mediated athetosis did not require caspase activation, early mitochondrial disruption or generation of reactive oxygen species, but did require an intact actin cytoskeleton and was abolished by latrunculin B and mycalolide B. This work defines an authentic role for mouse Gzm A in granule-induced cell death by cytotoxic lymphocytes.  相似文献   
4.

Background

Dengue has emerged as one of the most important infectious diseases in the last five decades. Evidence indicates the expansion of dengue virus endemic areas and consequently the exponential increase of dengue virus infections across the subtropics. The clinical manifestations of dengue virus infection include sudden fever, rash, headache, myalgia and in more serious cases, spontaneous bleeding. These manifestations occur in children as well as in adults. Defining the epidemiology of dengue in a given area is critical to understanding the disease and devising effective public health strategies.

Methodology/Principal Findings

Here, we report the results from a prospective cohort study of 4380 adults in West Java, Indonesia, from 2000–2004 and 2006–2009. A total of 2167 febrile episodes were documented and dengue virus infections were confirmed by RT-PCR or serology in 268 cases (12.4%). The proportion ranged from 7.6 to 41.8% each year. The overall incidence rate of symptomatic dengue virus infections was 17.3 cases/1,000 person years and between September 2006 and April 2008 asymptomatic infections were 2.6 times more frequent than symptomatic infections. According to the 1997 WHO classification guidelines, there were 210 dengue fever cases, 53 dengue hemorrhagic fever cases (including one dengue shock syndrome case) and five unclassified cases. Evidence for sequential dengue virus infections was seen in six subjects. All four dengue virus serotypes circulated most years. Inapparent dengue virus infections were predominantly associated with DENV-4 infections.

Conclusions/Significance

Dengue virus was responsible for a significant percentage of febrile illnesses in an adult population in West Java, Indonesia, and this percentage varied from year to year. The observed incidence rate during the study period was 43 times higher than the reported national or provincial rates during the same time period. A wide range of clinical severity was observed with most infections resulting in asymptomatic disease. The circulation of all four serotypes of dengue virus was observed in most years of the study.  相似文献   
5.

Introduction

Dysregulation of acylcarnitines (AcylCNs) and amino acids metabolism have implicated in abnormality of fatty acid oxidation in type 2 diabetes (T2D). However, it is not well known whether altered plasma AcylCN, and amino acid profiles are associated with albuminuria or diabetic nephropathy (DN) in T2D.

Objective

The aim of this study was to elucidate alterations in plasma levels of AcylCNs and amino acids with respect to the T2D patients with various stages of albuminuria.

Methods

We recruited 52 healthy subjects as control, and 156 T2D patients which were divided into 52 normoalbuminuria, 52 microalbuminuria, and 52 macroalbuminuria. Plasma 37 AcylCNs and 12 amino acids were analyzed by tandem mass spectrometry.

Results

We found that T2D with normoalbuminuria and microalbuminuria had lower shot-, medium-, and long-chain AcylCNs, whereas T2D with macroalbuminuria had higher short-and medium-chain AcylCNs and lower long-chain AcylCNs than healthy subjects. Moreover, estimated glomerular filtration rate (eGFR) was a negative, independent and significant predictor of albumin to creatinine ratio (ACR) levels (β = ?0.376, P < 0.001), whereas plasma Low-density lipoprotein cholesterol (LDL-C) was significantly and positively associated with ACR levels (β = 0.169, P = 0.049). Furthermore, multivariate ordinal logistic regression analysis revealed that isobutyrylcarnitine (C4) was a positive, independent, and significant predictor of ACR levels with higher odds of having T2D patients with progression normoalbuminuria to microalbuminuria [OR = 9.93, 95 % CI (3.51–28.05), P < 0.001].

Conclusions

The findings suggest that plasma C4 may serve as a potential biomarker for the early stages of DN.
  相似文献   
6.
The unfolded protein response (UPR) contributes to chlamydial pathogenesis, as a source of lipids and ATP during replication, and for establishing the initial anti-apoptotic state of host cell that ensures successful inclusion development. The molecular mechanism(s) of UPR induction by Chlamydia is unknown. Chlamydia use type III secretion system (T3SS) effector proteins (e.g, the Translocated Actin-Recruiting Phosphoprotein (Tarp) to stimulate host cell's cytoskeletal reorganization that facilitates invasion and inclusion development. We investigated the hypothesis that T3SS effector-mediated assembly of myosin-II complex produces activated non-muscle myosin heavy chain II (NMMHC-II), which then binds the UPR master regulator (BiP) and/or transducers to induce UPR. Our results revealed the interaction of the chlamydial effector proteins (CT228 and Tarp) with components of the myosin II complex and UPR regulator and transducer during infection. These interactions caused the activation and binding of NMMHC-II to BiP and IRE1α leading to UPR induction. In addition, specific inhibitors of myosin light chain kinase, Tarp oligomerization and myosin ATPase significantly reduced UPR activation and Chlamydia replication. Thus, Chlamydia induce UPR through T3SS effector-mediated activation of NMMHC-II components of the myosin complex to facilitate infectivity. The finding provides greater insights into chlamydial pathogenesis with the potential to identify therapeutic targets and formulations.  相似文献   
7.
Osmoregulation was studied throughout the embryonic development of Astacus leptodactylus. Egg-carrying females were held in freshwater (FW) and in three dilute seawater media (200, 400, 600 mosm kg(-1), 6.8, 13.6, 20.4 per thousand salinity). In FW, changes in peri-embryonic fluid (PEF) and (when available) embryonic hemolymph osmolality were followed from newly-laid eggs to hatching (for an embryonic eye index, EI, of 430-450 microm) and in first-stage juveniles. The PEF and/or hemolymph osmolality remained stable at about 360-380 mosm kg(-1) from early to late (EI 410 microm) embryos; it decreased prior to hatching (EI 420 microm) and in newly-hatched juveniles, down to 290 mosm kg(-1). Artificial opening and removal of the egg membranes, followed by direct exposure to FW, demonstrated that the ability to hyper-osmoregulate, and consequently to survive, in FW appears in embryos with EI > or = 410 microm, i.e., only a few hours or days before hatching. Following a transfer to the dilute seawater media, the PEF/hemolymph osmolality increased slowly over 18-20 days and became isosmotic with the external media at 13.6 and 20.4 per thousand. The embryos died at EI 380-395 microm in these media, and only at 6.8 per thousand was the development completed until successful hatch. These results demonstrate that (1) the embryos become able to osmoregulate in FW shortly before hatching, (2) the embryos are osmo-protected in the eggs during their development, (3) embryonic development and hatching are possible up to a salinity of 7 per thousand. These results are discussed in relation to freshwater adaptation of crayfish.  相似文献   
8.
9.
To examine the effect of negatively charged steroidal amphiphiles on antimicrobial activity, two pairs of epimeric, dendritic tricarboxylato amphiphiles--4-(2-carboxyethyl)-4-[3-(5alpha-cholestan-3-yl)ureido]heptanedioic acid (1) and 4-(2-carboxyethyl)-4-[3-(5alpha-cholestan-3-yloxycarbonylmethyl)ureido]heptanedioic acid (2)--were synthesized. A broad antimicrobial screen of 11 microbes revealed that these amphiphiles only showed good activity against a methicillin-resistant isolate of Staphylococcus aureus (MRSA) and modest activity against an unrelated strain of S. aureus. The best activity, a minimal inhibitory concentration (MIC) of 27 microM, was found for the 3beta epimer of 1 against MRSA.  相似文献   
10.
Biofilm forming cells are distinctive from the well-investigatedplanktonic cells and exhibit a different type of gene expression.Several new Escherichia coli genes related to biofilm formationhave recently been identified through genomic approaches suchas DNA microarray analysis. However, many others involved inthis process might have escaped detection due to poor expression,regulatory mechanism, or genetic backgrounds. Here, we screeneda collection of single-gene deletion mutants of E. coli named‘Keio collection’ to identify genes required forbiofilm formation. Of the 3985 mutants of non-essential genesin the collection thus examined, 110 showed a reduction in biofilmformation nine of which have not been well characterized yet.Systematic and quantitative analysis revealed the involvementof genes of various functions and reinforced the importancein biofilm formation of the genes for cell surface structuresand cell membrane. Characterization of the nine mutants of function-unknowngenes indicated that some of them, such as yfgA that geneticallyinteracts with a periplasmic chaperone gene surA together withyciB and yciM, might be required for the integrity of outermembrane.  相似文献   
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