Mutations in the CLN3 gene are responsible for the neurodegenerative disorder Batten disease; however, the molecular basis of this disease remains unknown. In studying a mouse model for Batten disease, we report the presence of an autoantibody to glutamic acid decarboxylase (GAD65) in cln3-knockout mice serum that associates with brain tissue but is not present in sera or brain of normal mice. The autoantibody to GAD65 has the ability to inhibit the activity of glutamic acid decarboxylase. Furthermore, brains from cln3-knockout mice have decreased activity of glutamic acid decarboxylase as a result of the inhibition of this enzyme by the autoantibody, resulting in brain samples from cln3-knockout mice having elevated levels of glutamate as compared with normal. This elevated glutamate in the brain of cln3-knockout mice co-localizes with presynaptic markers. The decreased activity of GAD65 and increased levels of glutamate may have a causative role in astrocytic hypertrophy evident in cln3-knockout mice, and in altered expression of genes involved in the synthesis and utilization of glutamate that underlie a shift from synthesis to utilization of glutamate. An autoantibody to GAD65 is also present in sera of 20 out of 20 individuals tested who have Batten disease. Postmortem tissue shows decreased reactivity to an anti-GAD65 antibody that may be due to loss of GAD65-positive neurons or due to the reactive epitope being blocked by the presence of the autoantibody. We propose that an autoimmune response to GAD65 may contribute to a preferential loss of GABAergic neurons associated with Batten disease.

Background:Oral mucositis is the most frequently occurring painful and dose-limiting side-effect of radiation of the head and neck region. Few studies demonstrated that oral glutamine suspension may significantly reduce the duration and severity of objective oral mucositis during radiotherapy.Materials and Methods:A randomized, prospective single institutional case control study was performed between April 2012 and November 2012 comparing the influence of oral glutamine on radiation induced mucositis in head and neck malignancy patients. Seventy biopsy proven patients with head and neck cancer receiving primary or adjuvant radiation therapy were randomized to receive either oral glutamine suspension daily 2h before radiation in the study arm (10 g in 1000 ml of water) (n = 35) or nothing before radiation; control arm (n = 35).Results and Analysis:Total 32 patients (91.43%) in the glutamine arm and total 34 patients (97.15%) developed mucositis. Grade 3 mucositis (14.29%) and grade 4 mucositis (2.86%) in the study arm (who received oral glutamine) were significantly less (P = 0.02 and P = 0.04, respectively) in the glutamine arm. The mean duration of grade 3 or worse mucositis (grade 3 and grade 4) was significantly less (6.6 days vs. 9.2 days) in study arm with P < 0.001. Mean time of onset of mucositis was significantly delayed in patients who took glutamine in comparison to control arm with P < 0.001.Conclusion:Glutamine delays oral mucositis in the head neck cancer patients. Moreover, it reduces the frequency and duration of grade 3 and grade 4 mucositis.

Culture creates the context within which individuals experience life and comprehend moral meaning of illness, suffering and death. The ways the patient, family and the physician communicate and make decisions in the end-of-life care are profoundly influenced by culture. What is considered as right or wrong in the healthcare setting may depend on the socio-cultural context. The present article is intended to delve into the cross-cultural perspectives in ethical decision making in the end-of-life scenario. We attempt to address the dynamics of the roles of patient, family and physician therein across two countries from East and West, namely, India and Germany. In India, where illness is more a shared family affair than an individual incident, a physician is likely to respect the family's wishes and may withhold the [Symbol: see text]naked truth' about the diagnosis of a fatal disease to the patient. In Germany, a physician is legally required to inform the patient about the disease. In India, advance directive being virtually non-existent, the family acts as the locus of the decision-making process, taking into account the economic cost of available medical care. In Germany, advance directive is regarded as mandatory and healthcare is covered by insurance. Family and the physician appear to play larger roles in ethical decision making for patients in India than for those in Germany, who place greater emphasis on autonomy of the individual patient. Our study explicates how culture matters in ethical decision-making and why the bioethical discourse is necessary in the concrete realities of the socio-cultural context. To explore the possibility of finding a common ground of morality across different cultures while acknowledging and respecting cultural diversity, thus remains a formidable challenge for the bioethicists.

The BTN1 gene product of the yeast Saccharomyces cerevisiae is 39% identical and 59% similar to human CLN3, which is associated with the neurodegenerative disorder Batten disease. Furthermore, btn1-⌬ strains have an elevated activity of the plasma membrane H ؉ -ATPase due to an abnormally high vacuolar acidity during the early phase of growth. Previously, DNA microarray analysis revealed that btn1-⌬ strains compensate for the altered plasma membrane H ؉ -ATPase activity and vacuolar pH by elevating the expression of the two genes HSP30 and BTN2. We now show that deletion of either HSP30 or BTN2 in either BTN1؉ or btn1-⌬ strains does not alter vacuolar pH but does lead to an increased activity of the vacuolar H ؉ -ATPase. Deletion of BTN1, BTN2, or HSP30 does not alter cytosolic pH but diminishes pH buffering capacity and causes poor growth at low pH in a medium containing sorbic acid, a condition known to result in disturbed intracellular pH homeostasis. Btn2p was localized to the cytosol, suggesting a role in mediating pH homeostasis between the vacuole and plasma membrane H ؉ -ATPase. Increased expression of HSP30 and BTN2 in btn1-⌬ strains and diminished growth of btn1-⌬, hsp30-⌬, and btn2-⌬ strains at low pH reinforce our view that altered pH homeostasis is the underlying cause of Batten disease.

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Btn2p, a novel cytosolic coiled-coil protein in Saccharomyces cerevisiae, was previously shown to interact with and to be necessary for the correct localization of Rhb1p, a regulator of arginine uptake, and Yif1p, a Golgi protein. We now report the biochemical and physical interactions of Btn2p with Ist2p, a plasma membrane protein that is thought to have a function in salt tolerance. A deletion in Btn2p (btn2⌬ strains) results in a failure to correctly localize Ist2p, and strains lacking Btn2p and Ist2p (btn2⌬ ist2⌬ strains) are unable to grow in the presence of 0.5 or 1.0 M NaCl. Btn2p was originally identified as being up-regulated in a btn1⌬ strain, which lacks the vacuolar-lysosomal membrane protein, Btn1p, and serves as a model for Batten disease. This up-regulation of Btn2p was shown to contribute to the maintenance of a stable vacuolar pH in the btn1⌬ strain. Btn1p was subsequently shown to be required for the optimal transport of arginine into the vacuole. Interestingly, btn1⌬ ist2⌬ strains are also unable to grow in the presence of 0.5 or 1.0 M NaCl, and ist2⌬ suppresses the vacuolar arginine transport defect in btn1⌬ strains. Although further investigation is required, we speculate that altered vacuolar arginine transport in btn1⌬ strains represents a mechanism for maintaining or balancing cellular ion homeostasis. Btn2p interacts with at least three proteins that are seemingly involved in different biological functions in different subcellular locations. Due to these multiple interactions, we conclude that Btn2p may play a regulatory role across the cell in response to alterations in the intracellular environment that may be caused by changes in amino acid levels or pH, a disruption in protein trafficking, or imbalances in ion homeostasis resulting from either genetic or environmental manipulation.

Btn2p, a novel coiled-coil protein, is up-regulated in btn1⌬ yeast strains, and this up-regulation is thought to contribute to maintaining a stable vacuolar pH in btn1⌬ strains (D. A. Pearce, T. Ferea, S. A. Nosel, B. Das, and F. Sherman, Nat. Genet. 22:55-58, 1999). We now report that Btn2p interacts biochemically and functionally with Rsg1p, a down-regulator of the Can1p arginine and lysine permease. Rsg1p localizes to a distinct structure toward the cell periphery, and strains lacking Btn2p (btn2⌬ strains) fail to correctly localize Rsg1p. btn2⌬ strains, like rsg1⌬ strains, are sensitive for growth in the presence of the arginine analog canavanine. Furthermore, btn2⌬ strains, like rsg1⌬ strains, demonstrate an elevated rate of uptake of [ 14 C]arginine, which leads to increased intracellular levels of arginine. Overexpression of BTN2 results in a decreased rate of arginine uptake. Collectively, these results indicate that altered levels of Btn2p can modulate arginine uptake through localization of the Can1p-arginine permease regulatory protein, Rsg1p. Our original identification of Btn2p was that it is up-regulated in the btn1⌬ strain which serves as a model for the lysosomal storage disorder Batten disease. Btn1p is a vacuolar/lysosomal membrane protein, and btn1⌬ suppresses both the canavanine sensitivity and the elevated rate of uptake of arginine displayed by btn2⌬ rsg1⌬ strains. We conclude that Btn2p interacts with Rsg1p and modulates arginine uptake. Up-regulation of BTN2 expression in btn1⌬ strains may facilitate either a direct or indirect effect on intracellular arginine levels.

Infantile and juvenile neuronal ceroid lipofuscinosis (NCLs) are progressive neurodegenerative disorders of childhood with distinct ages of clinical onset, but with a similar pathological outcome. Infantile and juvenile NCL are inherited in an autosomal recessive manner due to mutations in the CLN1 and CLN3 genes, respectively. Recently developed Cln1-and Cln3-knockout mouse models share similarities in pathology with the respective human disease. Using oligonucleotide arrays we identi¢ed reproducible changes in gene expression in the brains of both 10-week-old Cln1-and Cln3-knockout mice as compared to wild-type controls, and con¢rmed changes in levels of several of the cognate proteins by immunoblotting. Despite the similarities in pathology, the two mutations a¡ect the expression of di¡erent, non-overlapping sets of genes. The possible signi¢cance of these changes and the pathological mechanisms underlying NCL diseases are discussed. ß