Ca2؉ -regulated exocytosis of lysosomes has been recognized recently as a ubiquitous process, important for the repair of plasma membrane wounds. Lysosomal exocytosis is regulated by synaptotagmin VII, a member of the synaptotagmin family of Ca 2؉ -binding proteins localized on lysosomes. Here we show that Ca 2؉ -dependent interaction of the synaptotagmin VII C 2 A domain with SNAP-23 is facilitated by syntaxin 4. Specific interactions also occurred in cell lysates between the plasma

The intracellular protozoan parasite Trypanosoma cruzi causes Chagas' disease, which affects millions of people in Latin America. T. cruzi enters a large number of cell types by an unusual mechanism that involves Ca2+-triggered fusion of lysosomes with the plasma membrane. Here we show that synaptotagmin VII (Syt VII), a ubiquitously expressed synaptotagmin isoform that regulates exocytosis of lysosomes, is localized on the membranes of intracellular vacuoles containing T. cruzi. Antibodies against the C2A domain of Syt VII or recombinant peptides including this domain inhibit cell entry by T. cruzi, but not by Toxoplasma gondii or Salmonella typhimurium. The C2A domains of other ubiquitously expressed synaptotagmin isoforms have no effect on T. cruzi invasion, and mutation of critical residues on Syt VII C2A abolish its inhibitory activity. These findings indicate that T. cruzi exploits the Syt VII–dependent, Ca2+-regulated lysosomal exocytic pathway for invading host cells.

Medical students often experience significant stress during their undergraduate training. Evidence has shown short-term yoga to be effective in decreasing stress in students. This study aimed to assess knowledge about, attitude toward, and practice of (KAP) yoga among medical students. A secondary objective was to analyze their dietary habits and physical activity. Participants consisted of 224 medical students aged 18-23 years in pre- and paraclinical groups. A closed-ended KAP questionnaire was used to collect data. Anthropometric measurements were taken. Results showed that paraclinical students (70.5%) favorably perceived the health benefits of yoga. Nearly three-fourths of study subjects had previously practiced yoga; greater numbers intended to practice yoga in the future. About 95.5% of the preclinical students who had done yoga had discontinued the practice. Perceived barriers to the practice of yoga were lack of time, insufficient facilities, lack of company, and lack of interest. Consideration of the undergraduates' lifestyle revealed that 50.4% of preclinical students did not exercise, and they routinely consumed more junk food with fewer servings of fresh fruits/salads. Preclinical students exhibited higher BMI and waist circumference compared to paraclinical students. Findings suggest that knowledge of and attitude regarding yoga were good among medical undergraduates.

A p r o t o t y p e of an i n t e l l i g e n t w h e e l c h a i r (INCH) has been equipped w i t h u l t r a s o u n d range s e n s o r s and a Motorola 68HCl1, an i n e x p e n s i v e m i c r o c o n t r o l l e r . INCH was designed t o d e t e c t f a l l -o f f s and o b j e c t s i n i t s p a t h , t h e r e b y address i n g t h e needs of v i s u a l l y impaired p e r s o n s who have been c o n f i n e d t o w h e e l c h a i r s . Range informat i o n was d e r i v e d from a s e t of s i x P o l a r o i d u l t r a s o u n d t r a n s d u c e r s c o n t r o l l e d by custom e l e c t r o n i c s . Two Airpax s t e p p e r motors were used t o d r i v e t h e wheels. I n p u t provided by a s t a n d a r d analog j o y s t i c k i n d i c a t e d t h e d e s i r e d speed and d i r e c t i o n of motion. The l i m i t a t i o n s of I N C H a r e d i s c u s s e d and a m u l t i -s e n s o r approach t o improve t h e performance i s suggested.