Terahertz emission in ladder plus Y-configurations in double quantum dot structure

The ladder plus Y-double quantum dot (QD) structure has been proposed to improve the second-order nonlinear susceptibility (SONS) under applied electric field. For this purpose, the wetting layer (WL) and QD inhomogeneity contribution in SONS has been considered. In addition, the structure size effect, energy level separation, momentum matrix elements, and pump detuning have been examined, and show that the SONS is increased by using the WL, a low momentum matrix element of WL-QD transition in comparison with interdot transition while QD inhomogeneity reduces SONS to half. This work is predicted to play a key role in terahertz applications, since the frequency emissions obtained are in the range of 75.5-600 μm.

Experimental infection of brown-marbled grouper, Epinephelus fuscoguttatus (Forskal), with Vibrio parahaemolyticus identifies parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain, differentially expressed in resistant grouper

The mechanisms through which brown-marbled grouper accomplishes resistance to infection, particularly against Vibrios, are not yet fully understood. In this study, brown-marbled grouper fingerlings were experimentally infected with Vibrio parahaemolyticus, to identify disease resistance grouper, and the serum proteome profiles were compared between resistant and susceptible candidates, via two-dimensional gel electrophoresis (2-DE). The results showed that putative parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain proteins were among proteins that significantly overexpressed in the resistant fish as compared to the susceptible group of fish, whereas apolipoprotein E and immunoglobulin light chain proteins were observed to be differentially overexpressed in the susceptible fish. Further analysis by peptide sequencing revealed that the immunoglobulin light chain proteins identified in the resistant and susceptible groups differed in amino acid composition. Taken together, the results demonstrated for the first time that putative parvalbumin beta-2 subunit I, alpha-2-macroglobulin, nattectin and immunoglobulin light chain are among important proteins participating to effect disease resistance mechanism in fish and were overexpressed to function collectively to resist V. parahaemolyticus infection. Most of these molecules are mediators of immune response.

Complications of neck dissection at a tertiary level hospital: study of 30 cases

Metastatic dissemination into lymph nodes of neck occurs frequently in head neck cancers which down grade the patient's curability and survival. Neck dissection is a curable option for its management. To evaluate the complications following different types of neck dissection. This cross sectional study was conducted among patients undergone different types of neck dissection due to cervical nodal metastasis and attended follow up during July 2010 to June 2011 in Department of ENTs and Head-Neck surgery Dhaka Medical College Hospital, Dhaka, Bangladesh. Among 30 selected patient, 23 were male (76.67%) and 7 were female (23.33%), age ranged from 31-72 years (Mean=59.1±5.44). In different modalities of neck dissection 11 were modified neck dissection (36.67%) and 10(33.33%) were radical neck dissection. Common indication was carcinoma of unknown origin (66.67%). Involved neck nodes were commonly level II-IV (69.99%). Nodal stage was N2(50%) and N3 (40%).Common immediate complications were bleeding 03(10%), facial oedema 02 (6.67%) and thoracic duct injury 02(6.67%). Intermediate complications were seroma 05(16.67%), wound infection 04(13.33%) and chylous fistula 02(6.67%), Late Complications were hypertrophic scar 07(23.33%) and shoulder syndrome 06(20%). Proper indications, skilled surgery along with early recognize and treatment in both early and late manifestations of neck dissection preventing its grave sequence.

Pairing as an instructional strategy to promote soft skills amongst clinical dental students

Training dentists today is challenging as they are expected to provide a wide range of dental care. In the provision of good dental care, soft skills are equally important as clinical skills. Therefore in dental education the development of soft skills are of prime concern. This study sought to identify the development of soft skills when dental students are paired in their clinical training. In this perception study, four open-ended items were used to elicit students' feedback on the appropriateness of using clinical pairing as an instructional strategy to promote soft skills. The most frequently cited soft skills were teamwork (70%) and communication (25%) skills. However, both negative and positive behaviours were reported. As for critical thinking and problem solving skills, more positive behaviours were reported for abilities such as to explain, analyze, find ideas and alternative solutions, and make decisions. Leadership among peers was not evident as leading without legitimate authority could be a hindrance to its development. If clinical pairing is to be used as an effective instructional strategy to promote soft skills amongst students, clear guidelines need to be developed to prepare students to work in a dental team and the use of appropriate assessment tools can facilitate the development of these soft skills.

Adult motor axons preferentially reinnervate predegenerated muscle nerve

Preferential motor reinnervation (PMR) is the tendency for motor axons regenerating after repair of mixed nerve to reinnervate muscle nerve and/or muscle rather than cutaneous nerve or skin. PMR may occur in response to the peripheral nerve pathway alone in juvenile rats (Brushart, 1993; Redett et al., 2005), yet the ability to identify and respond to specific pathway markers is reportedly lost in adults (Uschold et al., 2007). The experiments reported here evaluate the relative roles of pathway and end organ in the genesis of PMR in adult rats. Fresh and 2-week predegenerated femoral nerve grafts were transferred in correct or reversed alignment to replace the femoral nerves of previously unoperated Lewis rats. After 8 weeks of regeneration the motoneurons projecting through the grafts to recipient femoral cutaneous and muscle branches and their adjacent end organs were identified by retrograde labeling. Motoneuron counts were subjected to Poisson regression analysis to determine the relative roles of pathway and end organ identity in generating PMR. Transfer of fresh grafts did not result in PMR, whereas substantial PMR was observed when predegenerated grafts were used. Similarly, the pathway through which motoneurons reached the muscle had a significant impact on PMR when grafts were predegenerated, but not when they were fresh. Comparison of the relative roles of pathway and end organ in generating PMR revealed that neither could be shown to be more important than the other. These experiments demonstrate unequivocally that adult muscle nerve and cutaneous nerve differ in qualities that can be detected by regenerating adult motoneurons and that can modify their subsequent behavior. They also reveal that two weeks of Wallerian degeneration modify the environment in the graft from one that provides no modality-specific cues for motor neurons to one that actively promotes PMR.

Transcatheter aortic valve replacement for advanced valvular disease in active SLE and APS

Valvular heart disease is a relatively common finding in systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS), sometimes necessitating valve surgery. Valve replacement may result in significant early and late morbidity and mortality. Surgical risks are even greater when co-morbid conditions including active SLE and renal involvement are present. This is the first report of the successful use of transcatheter aortic valve replacement (TAVR) for severe critical aortic stenosis in a patient with active SLE, renal failure and APS. TAVR may represent an additional, safer, approach to cardiac valve replacement in appropriately selected patients particularly where surgical risk is high and active disease present.

SLC2A2 mutations can cause neonatal diabetes, suggesting GLUT2 may have a role in human insulin secretion

AIMS

The gene SLC2A2 encodes GLUT2, which is found predominantly in pancreas, liver, kidney and intestine. In mice, GLUT2 is the major glucose transporter into pancreatic beta cells, and biallelic Slc2a2 inactivation causes lethal neonatal diabetes. The role of GLUT2 in human beta cells is controversial, and biallelic SLC2A2 mutations cause Fanconi-Bickel syndrome (FBS), with diabetes rarely reported. We investigated the potential role of GLUT2 in the neonatal period by testing whether SLC2A2 mutations can present with neonatal diabetes before the clinical features of FBS appear.

METHODS

We studied SLC2A2 in patients with transient neonatal diabetes mellitus (TNDM; n = 25) or permanent neonatal diabetes mellitus (PNDM; n = 79) in whom we had excluded the common genetic causes of neonatal diabetes, using a combined approach of sequencing and homozygosity mapping.

RESULTS

Of 104 patients, five (5%) were found to have homozygous SLC2A2 mutations, including four novel mutations (S203R, M376R, c.963+1G>A, F114LfsX16). Four out of five patients with SLC2A2 mutations presented with isolated diabetes and later developed features of FBS. Four out of five patients had TNDM (16% of our TNDM cohort of unknown aetiology). One patient with PNDM remains on insulin at 28 months.

CONCLUSIONS

SLC2A2 mutations are an autosomal recessive cause of neonatal diabetes that should be considered in consanguineous families or those with TNDM, after excluding common causes, even in the absence of features of FBS. The finding that patients with homozygous SLC2A2 mutations can have neonatal diabetes supports a role for GLUT2 in the human beta cell.

A phase 2 study of the combination of gemcitabine and cisplatin in patients with locally advanced or metastatic breast cancer previously treated with anthracyclines with/without taxanes

BACKGROUND AND OBJECTIVES

Many patients with relapsed metastatic breast cancer are pre-treated with taxanes and anthracyclines, which are usually given in the neoadjuvant/adjuvant setting or as first-line treatment for metastatic disease. The primary objective of this study was to determine the overall response rate for combination treatment with gemcitabine and cisplatin in patients with locally advanced or metastatic breast cancer who had relapsed after receiving one adjuvant/neoadjuvant or first-line metastatic chemotherapy regimen containing an anthracycline with/without a taxane. Secondary endpoints included duration of response, time to progression, one-year survival probability, and toxicity.

DESIGN AND SETTING

A single-arm, open-label, phase 2 study conducted at 17 investigative sites in Egypt.

PATIENTS AND METHODS

treatment consisted of gemcitabine (1250 mg/m2) on Days 1 and 8 and cisplatin (70 mg/m2) on Day 1 of each 21-day cycle. Treatment continued until disease progression or a maximum of 6 cycles.

RESULTS

Of 144 patients all were evaluable for safety and 132 patients were evaluable for efficacy. The overall response rate was 33.3% and 45.5% of the patients with stable disease as their best response. The median time-to-progression was 5.1 months and the one-year survival probability was 73%. The most common grade 3/4 adverse events were nausea/vomiting (20.1%), neutropenia (19.4%), anemia (13.9%), asthenia (11.1%), diarrhea (9.7%), stomatitis (7.6%), leucopenia (7.6%), and thrombocytopenia (6.2%). twelve (8.3%) patients had serious adverse events.

CONCLUSIONS

The results of this study indicate that gemcitabine and cisplatin were active and generally well tolerated in pretreated patients with locally advanced or metastatic breast cancer.

Electrical and Magnetic Properties of Polymer Electrolyte (PVA:LiOH) Containing In Situ Dispersed Fe3O4 Nanoparticles

Nanocomposite magnetic polymer electrolytes based on poly(vinyl alcohol) (PVA) complexed with lithium hydroxide (LiOH) and containing magnetite (Fe3O4) nanoparticles were prepared using an in situ method, in which the nanoparticles were grown in the host polymer electrolyte. Ion carriers were formed during nanoparticle growth from the previously added LiOH precursor. If a high concentration of LiOH was added, the remaining unreacted LiOH was distributed in the form of an amorphous complex around the Fe3O4 nanoparticles, thus preventing agglomeration of the nanoparticles by the host polymer. By addition of Fe3O4 the composite polymer electrolytes improved the ionic conductivity, resulting in a maximum conductivity of 1.81×10-3 S⋅cm-1. The magnetic properties of the polymer electrolyte were investigated through magnetic susceptibility studies, and the material was predominantly ferromagnetic.

Pulmonary haptoglobin and CD163 are functional immunoregulatory elements in the human lung

BACKGROUND

The acute-phase protein haptoglobin (Hp) and its receptor CD163 serve as immunomodulators and possess anti-inflammatory besides antioxidant functions.

OBJECTIVES

To further understand the role of the recently described pulmonary Hp (pHp) and its receptor CD163 in case of inflammation and infection, pHp and CD163 were investigated on mRNA and protein level to gain insight into the cellular events taking place upon stimulation with the inflammatory mediators LPS, Pam3, cytokine IL-6 and dexamethasone, and upon infection with respiratory pathogens (Haemophilus influenzae, Streptococcuspneumoniae and Chlamydia pneumoniae) by use of a human ex vivo tissue culture model and cell cultures of A549 and alveolar epithelial cells type II. In addition, pHp and CD163 expression in COPD and sarcoidosis was assessed.

METHODS

We conducted experiments using 942 ex vivo cultured lung samples applying immunohistochemistry, immunocytochemistry, in situ hybridization, immunofluorescence, real-time PCR, RT-PCR, slot and Western immunoblot analyses with tissue lysates and culture supernatants as well as ELISA and cytometric bead array analyses.

RESULTS

This study describes for the first time the expression, regulation and secretion of pHp and its receptor CD163 in the human lung. The release of soluble mediators from A549 cell line and human monocyte-derived macrophages was observed indicating that Hp differentially activates the release of soluble mediators and major chemoattractants.

CONCLUSIONS

The findings indicate a native function of pHp and CD163 as functional pulmonary defense elements due to local expression, regulation and secretion during lung infection and as part of the inflammatory immune response of the respiratory system.

Differentiation of dental pulp stem cells into islet-like aggregates

The post-natal dental pulp tissue contains a population of multipotent mesenchymal progenitor cells known as dental pulp stromal/stem cells (DPSCs), with high proliferative potential for self-renewal. In this investigation, we explored the potential of DPSCs to differentiate into pancreatic cell lineage resembling islet-like cell aggregates (ICAs). We isolated, propagated, and characterized DPSCs and demonstrated that these could be differentiated into adipogenic, chondrogenic, and osteogenic lineage upon exposure to an appropriate cocktail of differentiating agents. Using a three-step protocol reported previously by our group, we succeeded in obtaining ICAs from DPSCs. The identity of ICAs was confirmed as islets by dithiozone-positive staining, as well as by expression of C-peptide, Pdx-1, Pax4, Pax6, Ngn3, and Isl-1. There were several-fold up-regulations of these transcription factors proportional to days of differentiation as compared with undifferentiated DPSCs. Day 10 ICAs released insulin and C-peptide in a glucose-dependent manner, exhibiting in vitro functionality. Our results demonstrated for the first time that DPSCs could be differentiated into pancreatic cell lineage and offer an unconventional and non-controversial source of human tissue that could be used for autologous stem cell therapy in diabetes.

Mesenchymal stem cells inhibit proliferation of lymphoid origin haematopoietic tumour cells by inducing cell cycle arrest

We have previously shown that mesenchymal stem cells (MSC) inhibit tumour cell proliferation, thus promising a novel therapy for treating cancers. In this study, MSC were generated from human bone marrow samples and characterised based on standard immunophenotyping. When MSC were co-cultured with BV173 and Jurkat tumour cells, the proliferation of tumour cells were profoundly inhibited in a dose dependent manner mainly via cell to cell contact interaction. Further cell cycle analysis reveals that MSC arrest tumour cell proliferation in G0/G1 phase of cell cycle thus preventing the entry of tumour cells into S phase of cell cycle.