360 research outputs found
New potential treatments for protection of pancreatic B-cell function in Type 1 diabetes
Type 1 diabetes mellitus results from the progressive and specific autoimmune destruction of insulin-secreting pancreatic B-cells, which develops over a period of years and continues after the initial clinical presentation. The ultimate goal of therapeutic intervention is prevention or reversal of the disease by the arrest of autoimmunity and by preservation/restoration of B-cell mass and function. Recent clinical trials of antigen-specific or non-specific immune therapies have proved that modulation of islet specific autoimmunity in humans and prevention of insulin secretion loss in the short term after the onset of disease is achievable. The identification of suitable candidates for therapy, appropriate dosage and timing, specificity of intervention and the side-effect profile are crucial for the success of any approach. Considering the complexity of the disease, it is likely that a rationally designed approach of combined immune-based therapies that target suppression of B-cell specific autoreactivity and maintenance of immune tolerance, coupled with islet regeneration or replacement of the destroyed B-cell mass, will prove to be most effective in causing remission/reversal of disease in a durable fashion
Multiferroic (Nd,Fe)-doped PbTiO3 ceramics with coexistent ferroelectricity and magnetism at room temperature
We report the structural, dielectric, elastic, ferroelectric and ferromagnetic properties of multiferroic (Nd, Fe)-doped PbTiO3 perovskite ceramics with composition (Pb 0.88 Nd 0.08 )(Ti 0.94 Fe 0.04 Mn 0.02 )O 3 , prepared by different solid state reaction methods: the first one based on a single-stage calcination (Method I) and the second based on a double-stage calcination (Method II). Structural, dielectric and anelastic measurements evidenced a double phase transition for samples prepared by Method I, which has been attributed to phase separation. This phase separation has been confirmed also by TEM and HRTEM investigations. Samples prepared by Method II showed a single phase transition from paraelectric to ferroelectric phase. We found coexistent ferroelectric and ferromagnetic properties, also at room-temperature, but only for ceramics prepared by Method II. The crucial role of calcination process for avoiding phase separation and obtaining homogeneous structures with ferroelectric and ferromagnetic order is underlined
Surgical approach to medullary thyroid carcinoma associated with multiple endocrine neoplasia type 2
We briefly review the surgical approaches to medullary thyroid carcinoma associated with multiple endocrine neoplasia type 2 (medullary thyroid carcinoma/multiple endocrine neoplasia type 2). The recommended surgical approaches are usually based on the age of the affected carrier/patient, tumor staging and the specific rearranged during transfection codon mutation. We have focused mainly on young children with no apparent disease who are carrying a germline rearranged during transfection mutation. Successful management of medullary thyroid carcinoma in these cases depends on early diagnosis and treatment. Total thyroidectomy should be performed before 6 months of age in infants carrying the rearranged during transfection 918 codon mutation, by the age of 3 years in rearranged during transfection 634 mutation carriers, at 5 years of age in carriers with level 3 risk rearranged during transfection mutations, and by the age of 10 years in level 4 risk rearranged during transfection mutations. Patients with thyroid tumor >5 mm detected by ultrasound, and basal calcitonin levels >40 pg/ml, frequently have cervical and upper mediastinal lymph node metastasis. In the latter patients, total thyroidectomy should be complemented by extensive lymph node dissection. Also, we briefly review our data from a large familial medullary thyroid carcinoma genealogy harboring a germline rearranged during transfection Cys620Arg mutation. All 14 screened carriers of the rearranged during transfection Cys620Arg mutation who underwent total thyroidectomy before the age of 12 years presented persistently undetectable serum levels of calcitonin (<2 pg/ml) during the follow-up period of 2–6 years. Although it is recommended that preventive total thyroidectomy in rearranged during transfection codon 620 mutation carriers is performed before the age of 5 years, in this particular family the surgical intervention performed before the age of 12 years led to an apparent biochemical cure
Protected areas: a resource or constraint for local people?
We investigated local people’s perceptions, knowledge, and attitudes toward conservation planning and management in Chitral Gol National Park in North West Frontier Province (NWFP) of Pakistan. A literature review was undertaken to unravel the historic drivers behind the formation of this protected area. Key informant interviews and questionnaire surveys were conducted to evaluate the effectiveness of current governance approaches adopted by the park management authorities. Community-based questionnaire surveys and key-informant interviews focused on local communities’ knowledge and awareness of the objectives of the park, people’s role in decision-making, social characteristics, and resource use structures. The information from these surveys was evaluated within the context of good governance and sustainability of park management. Results show a lack of awareness and a low level of participation in protected area management, but a high degree of willingness in the communities to participate in conservation activities. An analysis of the survey data suggests that the park authorities enforce strict protection measures within the park, but this approach lacks a strong vision of sustainability. The surveys reveal that the local people have a very strong sense of belonging to the place and are willing to contribute to the protection of the PA. A large majority of the respondents rely on electronic media as their main source of information, which could potentially form the best medium for conservation campaigning in the region. With these findings in mind, we propose changes to the current governance model for effective and sustainable management of the park in the future
Kisspeptin, neurokinin B, and dynorphin cct in the arcuate nucleus to control activity of the GnRH pulse generator in Ewes
Recent work has led to the hypothesis that kisspeptin/neurokinin B/dynorphin (KNDy) neurons in
the arcuate nucleus play a key role in GnRH pulse generation, with kisspeptin driving GnRH release
and neurokinin B (NKB) and dynorphin acting as start and stop signals, respectively. In this study,
we tested this hypothesis by determining the actions, if any, of four neurotransmitters found in
KNDy neurons (kisspeptin, NKB, dynorphin, and glutamate) on episodic LH secretion using local
administration of agonists and antagonists to receptors for these transmitters in ovariectomized
ewes. We also obtained evidence that GnRH-containing afferents contact KNDy neurons, so we
tested the role of two components of these afferents: GnRH and orphanin-FQ. Microimplants of
a Kiss1r antagonist briefly inhibited LH pulses and microinjections of 2 nmol of this antagonist
produced a modest transitory decrease in LH pulse frequency. An antagonist to the NKB receptor
also decreased LH pulse frequency, whereas NKB and an antagonist to the receptor for dynorphin
both increased pulse frequency. In contrast, antagonists toGnRHreceptors, orphanin-FQ receptors,
and the N-methyl-D-aspartate glutamate receptor had no effect on episodic LH secretion.Wethus
conclude that the KNDy neuropeptides act in the arcuate nucleus to control episodic GnRH secretion
in the ewe, but afferent input from GnRH neurons to this area does not. These data support
the proposed roles forNKBand dynorphin within theKNDyneural network and raise the possibility
that kisspeptin contributes to the control ofGnRHpulse frequency in addition to its established role
as an output signal from KNDy neurons that drives GnRH pulses.National Institutes of Health
Grants R01-HD039916 and RO1-HD017864.http://press.endocrine.org/journal/endoam201
Revisiting the association between candidal infection and carcinoma, particularly oral squamous cell carcinoma
Background: Tobacco and alcohol are risk factors associated with cancer of the upper aerodigestive tract, but increasingly the role of infection and chronic inflammation is recognized as being significant in cancer development. Bacteria, particularly Helicobacter pylori, and viruses such as members of the human papilloma virus family and hepatitis B and C are strongly implicated as etiological factors in certain cancers. There is less evidence for an association between fungi and cancer, although it has been recognized for many years that white patches on the oral mucosa, which are infected with Candida, have a greater likelihood of undergoing malignant transformation than those that are not infected. Objective: This article reviews the association between the development of oral squamous cell carcinoma in potentially malignant oral lesions with chronic candidal infection and describes mechanisms that may be involved in Candida-associated malignant transformation
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