Regulation of oocyte and cumulus cell interactions by intermedin/adrenomedullin 2

Ovarian folliculogenesis has been studied as a model of hormonal regulation of development and differentiation, cell death, and cell-cell communication. In addition to gonadotropins from the pituitary and follicular paracrine factors, oocyte secreted factors have been shown to play critical roles in the regulation of follicular cell functions. Except for the well characterized BMP family proteins, including GDF9 and BMP15, oocytes are known to secrete oocyte secreted factors that are important for the regulation of cumulus cell survival and the maintenance of tertiary structure of cumulus cell-enclosed oocyte complexes (COCs). Based on genomic screening and studies of COCs cultured in vitro, we showed that intermedin (IMD)/adrenomedullin 2 (ADM2) is a novel oocyte-derived ligand important for the regulation of cell interactions in COCs that functions, in part, by suppressing cumulus cell apoptosis. Consistently, we showed that suppression of IMD/ADM2 signaling in growing rat ovaries in vivo leads to oocyte atresia and aberrant cell cycle progression in follicular cells. Together, our studies indicated that mammalian oocytes deploy a G protein-coupled receptor ligand to coordinate normal interactions of oocytes and cumulus cells and provided a better understanding of how the tertiary structure of a COC is maintained as follicles undergo exponential growth during the late stages of folliculogenesis.     

Alternative Splicing Generates a Novel Truncated Cav1.2 Channel in Neonatal Rat Heart

L-type Ca_v1.2 Ca²⁺ channel undergoes extensive alternative splicing, generating functionally different channels. Alternatively spliced Ca_v1.2 Ca²⁺ channels have been found to be expressed in a tissue-specific manner or under pathological conditions. To provide a more comprehensive understanding of alternative splicing in Ca_v1.2 channel, we systematically investigated the splicing patterns in the neonatal and adult rat hearts. The neonatal heart expresses a novel 104-bp exon 33L at the IVS3-4 linker that is generated by the use of an alternative acceptor site. Inclusion of exon 33L causes frameshift and C-terminal truncation. Whole-cell electrophysiological recordings of Ca_v1.2_33L channels expressed in HEK 293 cells did not detect any current. However, when co-expressed with wild type Ca_v1.2 channels, Ca_v1.2_33L channels reduced the current density and altered the electrophysiological properties of the wild type Ca_v1.2 channels. Interestingly, the truncated 3.5-domain Ca_v1.2_33L channels also yielded a dominant negative effect on Ca_v1.3 channels, but not on Ca_v3.2 channels, suggesting that Ca_vβ subunits is required for Ca_v1.2_33L regulation. A biochemical study provided evidence that Ca_v1.2_33L channels enhanced protein degradation of wild type channels via the ubiquitin-proteasome system. Although the physiological significance of the Ca_v1.2_33L channels in neonatal heart is still unknown, our report demonstrates the ability of this novel truncated channel to modulate the activity of the functional Ca_v1.2 channels. Moreover, the human Ca_v1.2 channel also contains exon 33L that is developmentally regulated in heart. Unexpectedly, human exon 33L has a one-nucleotide insertion that allowed in-frame translation of a full Ca_v1.2 channel. An electrophysiological study showed that human Ca_v1.2_33L channel is a functional channel but conducts Ca²⁺ ions at a much lower level.     

A Possible Case of Cherubism in a 17th-Century Korean Mummy

Cherubism is a benign fibro-osseous disease of childhood limited specifically to the maxilla and mandible. The progressive replacement of the jaw bones with expansile multilocular cystic lesions causes eventual prominence of the lower face, and hence the classic “cherubic” phenotype reflecting variable extents of jaw hypertrophy. Histologically, this condition has been characterized as replacement of the normal bone matrix with multicystic pockets of fibrous stroma and osteoclastic giant cells. Because of radiographic features common to both, primarily the presence of multiloculated lucencies with heterogeneous “ground-glass” sclerosis on CT imaging, cherubism was long mistaken for a craniofacial subtype of fibrous dysplasia. In 1999, however, the distinct genetic basis for cherubism was mapped to chromosome 4p16.3 and the SH-3 binding protein SH3BP2. But while there are already three suspected cases of fibrous dysplasia amongst archaeological populations, no definitive cases of cherubism have yet been reported in historical populations. In the current study we describe micro- and macro-structural changes in the face of a 17^th century Joseon Dynasty Korean mummy which may coincide with the clinic-pathologic and radiologic features of cherubism.     

Mutations in the gene PRRT2 cause paroxysmal kinesigenic dyskinesia with infantile convulsions

Paroxysmal Kinesigenic Dyskinesia with Infantile Convulsions (PKD/IC) is an episodic movement disorder with autosomal dominant inheritance and high penetrance, but the causative gene is unknown. We have now identified four truncating mutations involving the PRRT2 gene in the vast majority (24/25) of well characterized families with PKD/IC. PRRT2 truncating mutations were also detected in 28 of 78 additional families. The PRRT2 gene encodes a proline-rich transmembrane protein of unknown function that has been reported to interact with the t-SNARE, SNAP25. PRRT2 localizes to axons but not to dendritic processes in primary neuronal culture and mutants associated with PKD/IC lead to dramatically reduced PRRT2 protein levels leading ultimately to neuronal hyperexcitability that manifests in vivo as PKD/IC.     

Differences between Spinocerebellar Ataxias and Multiple System Atrophy-Cerebellar Type on Proton Magnetic Resonance Spectroscopy

Purpose

A broad spectrum of diseases can manifest cerebellar ataxia. In this study, we investigated whether proton magnetic resonance spectroscopy (MRS) may help differentiate spinocerebellar ataxias (SCA) from multiple systemic atrophy- cerebellar type (MSA-C).

Material and Methods

This prospective study recruited 156 patients with ataxia, including spinocerebellar ataxia (SCA) types 1, 2, 3, 6 and 17 (N = 94) and MSA-C (N = 62), and 44 healthy controls. Single voxel proton MRS in the cerebellar hemispheres and vermis were measured. The differences were evaluated using nonparametric statistic tests.

Results

When compared with healthy controls, the cerebellar and vermis NAA/Cr and NAA/Cho were lower in all patients(p<0.002). The Cho/Cr was lower in SCA2 and MSA-C (p<0.0005). The NAA/Cr and Cho/Cr were lower in MSA-C or SCA2 comparing with SCA3 or SCA6. The MRS features of SCA1 were in between (p<0.018). The cerebellar NAA/Cho was lower in SCA2 than SCA1, SCA3 or SCA6 (p<0.04). The cerebellar NAA/Cho in MSA-C was lower than SCA3 (p<0.0005). In the early stages of diseases (SARA score<10), significant lower NAA/Cr and NAA/Cho in SCA2, SCA3, SCA6 or MSA-C were observed comparing with healthy controls (p<0.017). The Cho/Cr was lower in MSA-C or SCA2 (p<0.0005). Patients with MSA-C and SCA2 had lower NAA/Cr and Cho/Cr than SCA3 or SCA6 (p<0.016).

Conclusion

By using MRS, significantly lower NAA/Cr, Cho/Cr and NAA/Cho in the cerebellar hemispheres and vermis were found in patients with ataxia (SCAs and MSA-C). Rapid neuronal degeneration and impairment of membrane activities were observed more often in patients with MSA-C than those with SCA, even in early stages. MRS could also help distinguish between SCA2 and other subtypes of SCAs. MRS ratios may be of use as biomarkers in early stages of disease and should be further assessed in a longitudinal study.     

Gymnophalloides seoi eggs from the stool of a 17th century female mummy found in Hadong, Republic of Korea

It was previously reported that paleoparasitological clues for parasites infecting humans could be found in the feces of mummies of the Joseon Dynasty (1392-1910) in the Republic of Korea. Here, we report the presence of trematode eggs, including Clonorchis sinensis, Metagonimus yokogawai, and Gymnophalloides seoi (a human parasite known in Korea since 1993) in the feces of a recently excavated female mummy in Hadong, Republic of Korea. This is the first report of the discovery of a G. seoi infection in a human mummy. Since Hadong is currently not an endemic area for G. seoi, we speculate that the parasite might have occurred frequently along coastal areas of the Korean peninsula several hundred years ago and that the endemic areas contracted to, more or less, restricted regions since that time.     

Pathogenic role of B cells and antibodies in murine Leishmania amazonensis infection

Leishmania amazonensis infection, occurring predominantly in Central and South America, can manifest itself in several forms, including those of cutaneous and diffuse cutaneous leishmaniasis. The outcome of L. amazonensis infection depends largely on host immune responses to the parasites. While CD4+ T cell activation is a prerequisite for pathogenesis in L. amazonensis-infected mice, the roles of B cells and their antibody production are unclear. In this study, we provide evidence suggesting that B cells and antibodies are involved in disease pathogenesis. We documented a correlation between B cell activation and lesion progress in immunocompetent mice. In the absence of functional B cells and antibodies, JhD mice showed a delayed onset of disease and developed small lesions. Histological examination of these mice revealed a significant reduction in CD4+ and CD8+ T cells, but not in MAC1+ macrophages, at the infection site. In contrast to the wild-type mice that showed typical tissue necrosis, L. amazonensis-infected JhD mice showed no or minimal signs of necrotic foci. A marked reduction in CD4+ T cell proliferation and cytokine (IFN-gamma and IL-10) production in infected JhD mice suggested an involvement of B cells and antibodies in the priming of parasite-specific T cells. This notion was further supported by the observations that adoptive transfer of B cells or antibodies could restore CD4+ T cell activation and migration in infected JhD mice. Moreover, antibody coating of parasites could stimulate dendritic cells to produce high levels of cytokines and increase their ability to prime nai ve CD4+ T cells. Since CD4+ T cells are crucial to disease pathogenesis, this study suggests that B cells and their antibody production enhanced L. amazonensis infection, partially by promoting T cell priming and cellular migration to the infection site.     

Do Post Discharge Phone Calls Improve Care Transitions? A Cluster-Randomized Trial

Importance

The transition from hospital to home can expose patients to adverse events during the post discharge period. Post discharge care including phone calls may provide support for patients returning home but the impact on care transitions is unknown.

Objective

To examine the effect of a 72-hour post discharge phone call on the patient''s transition of care experience.

Design

Cluster-randomized control trial.

Setting

Urban, academic medical center.

Participants

General medical patients age 18 and older discharged home after hospitalization.

Main Outcomes and Measures

Primary outcome measure was the Care Transition Measure (CTM-3) score, a validated measure of the quality of care transitions. Secondary measures included self-reported adherence to medication and follow up plans, and 30-day composite of emergency department (ED) visits and hospital readmission.

Results

328 patients were included in the study over an 6-month period. 114 (69%) received a post discharge phone call, and 214 of all patients in the study completed the follow outcome survey (65% response rate). A small difference in CTM-3 scores was observed between the intervention and control groups (1.87 points, 95% CI 0.47–3.27, p = 0.01). Self-reported adherence to treatment plans, ED visits, and emergency readmission rates were similar between the two groups (odds ratio 0.57, 95% CI 0.13–2.45, 1.20, 95% CI 0.61–2.37, and 1.18, 95% CI 0.53–2.61, respectively).

Conclusions and Relevance

A single post discharge phone call had a small impact on the quality of care transitions and no effect on hospital utilization. Higher intensity post discharge support may be required to improve the patient experience upon returning home.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01580774","term_id":"NCT01580774"}}NCT01580774     

Modulation of dendritic cell function by Leishmania parasites

The interactions between Leishmania parasites and dendritic cells (DCs) are complex and involve paradoxical functions that can stimulate or halt T cell responses, leading to the control of infection or progression of disease. The magnitude and profile of DC activation vary greatly, depending upon the Leishmania species/strains, developmental stages, DC subsets, serum opsonization, and exogenous DC stimuli involved in the study. In general, the uptake of Leishmania parasites alone can trigger relatively weak and transient DC activation; however, the intracellular parasites (amastigotes) are capable of down-modulating LPS/IFN-gamma-stimulated DC activation via multiple mechanisms. This review will highlight current data regarding the initial interaction of DC subsets with invading parasites, the alterations of DC signaling pathways and function by amastigotes, and the impact of DC functions on protective immunity and disease pathogenesis. Available information provides insight into the mechanisms by which DCs discriminate between the types of pathogens and regulate appropriate immune responses.     

Activation of NF-kappaB in airway epithelial cells is dependent on CFTR trafficking and Cl- channel function

Polymorphonuclear leukocyte-dominated airway inflammation is a major component of cystic fibrosis (CF) lung disease and may be associated with CF transmembrane conductance regulator (CFTR) dysfunction as well as infection. Mutant DeltaF508 CFTR is mistrafficked, accumulates in the endoplasmic reticulum (ER), and may cause "cell stress" and activation of nuclear factor (NF)-kappaB. G551D mutants also lack Cl- channel function, but CFTR is trafficked normally. We compared the effects of CFTR mutations on the endogenous activation of an NF-kappaB reporter construct. In transfected Chinese hamster ovary cells, the mistrafficked DeltaF508 allele caused a sevenfold activation of NF-kappaB compared with wild-type CFTR or the G551D mutant (P < 0.001). NF-kappaB was also activated in 9/HTEo-/pCep-R cells and in 16HBE/pcftr antisense cell lines, which lack CFTR Cl- channel function but do not accumulate mutant protein in the ER. This endogenous activation of NF-kappaB was associated with elevated interleukin-8 expression. Impaired CFTR Cl- channel activity as well as cell stress due to accumulation of mistrafficked CFTR in the ER contributes to the endogenous activation of NF-kappaB in cells with the CFTR mutation.