Distribution of calcium-activated neutral proteinase activity in quaking mouse brain: a subcellular study

The distribution of calcium-activated neutral proteinase (CANP) activity was examined in the subcellular fractions of quaking and control mouse brain. The CANP activity was determined in purified myelin, cytosol and pellet (P2, consisting of nuclei, mitochondria and microsomes) fractions using [14C]azocasein as substrate. The enzyme activity in quaking brain was 1.3-fold greater than control. Fifty-seven percent of the control brain activity was in purified myelin compared to only 7% in quaking myelin. The specific activity of the control purified myelin was 4-fold greater than homogenate while that of the quaking was two-fold greater. In contrast, 51% of the quaking brain activity was present in cytosol compared to only 18% in the control. Triton X-100 greatly increased the control brain activity (10-fold) while the quaking brain activity was increased by only 1.2-fold. The total calcium content in the quaking brain was greatly elevated (6-fold) compared to control. Approximately 30% of the brain 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) activity was in quaking myelin while 77% of the CNPase activity in control brain was in myelin. These results suggest that in quaking brain much of the CANP is not incorporated into the myelin membrane and remains cytosolic.     

A study of morbidity pattern,nutritional status and various defects of urban primary school children in Delhi

Summary The morbidity pattern, nutritional deficiencies and various defects of the special senses, among 2773 primary school children in an urban community of Delhi are presented. The relevant literature is reviewed briefly and the preventable causes of illness highlighted. From the Survey on Morbidity and Mortality, Growth and Development, and Nutritional Status of Children in Delhi. Post Address: Flat 32, Shankar Market, New Delhi-1.     

Increased calpain content and progressive degradation of neurofilament protein in spinal cord injury

Spinal cord injury was induced in rat by weight drop. The extent of degradation of neurofilament proteins in the lesion following trauma was examined and served as a measure of calpain activity. Calpain was identified in the samples by myelin mealpain antibody and the content was estimated from the immunoblot. There was progressive degradation of both 68 kDa and 200 kDa neurofilament proteins in the cord lesion at intervals after injury. At 30 min after injury there was 20% degradation of both neurofilament proteins while the breakdown of 68 kDa and 200 kDa NFRs amounted to more than 60% at 24 h and beyond. Calpain content progressively increased in the lesion by 22% at 30 min to 91% at 4 h after trauma compared to control and then decreased but remained elevated for up to 72 h following injury. These results suggest that calpain is a primary responder synthesized early in injury and involved initially in the breakdown of cytoskeletal proteins in spinal cord trauma. Later in the injury cascade, increased calpain activity is derived from inflammatory as well as endogenous cells supporting a pivotal role for calpain throughout the process of secondary and evolving tissue damage in spinal cord trauma.     

Synthesis of microtubule-interfering halogenated noscapine analogs that perturb mitosis in cancer cells followed by cell death

We have previously identified the naturally occurring non-toxic antitussive phthalideisoquinoline alkaloid, noscapine as a tubulin-binding agent that arrests mitosis and induces apoptosis. Here we present high-yield efficient synthetic methods and an evaluation of anticancer activity of halogenated noscapine analogs. Our results show that all analogs display higher tubulin-binding activity than noscapine and inhibit proliferation of human cancer cells (MCF-7, MDA-MB-231 and CEM). Surprisingly, the bromo-analog is ∼40-fold more potent than noscapine in inhibiting cellular proliferation of MCF-7 cells. The ability of these analogs to inhibit cellular proliferation is mediated by cell cycle arrest at the G₂/M phase, in that all analogs except 9-iodonoscapine, caused selective mitotic arrest with a higher efficiency than noscapine followed by apoptotic cell death as shown by immunofluorescence and quantitative FACS analyses. Furthermore, our results reveal the appearance of numerous fragmented nuclei as evidenced by DAPI staining. Thus, our data indicate a great potential of these compounds for studying microtubule-mediated processes and as chemotherapeutic agents for the management of human cancers.     

Plasma catecholamine levels and neurobehavioral problems in Indian firefighters

Firefighting is a stressful and hazardous job. Persons engaged in firefighting are highly exposed to work-related stress as well as to smoke containing a host of chemicals potentially harmful to human health. In order to elucidate whether firefighting affects neuroendocrine and behavioral responses of firefighters, plasma catecholamine (CA) levels and the prevalence of neurobehavioral symptoms in 62 firefighters (all males, mean age 43 yr) and 52 control subjects matched for age and sex were examined in this study. Self-reported neurobehavioral symptoms data were obtained from a questionnaire survey and personal interview. Concentrations of epinephrine (E), norepinephrine (NE) and dopamine (DA) in plasma were measured by high-performance liquid chromatography with electrochemical detection. Compared with matched controls, the firefighters showed higher prevalence (p<0.05) of neurobehavioral symptoms such as burning sensation in the extremities, tingling and numbness, transient loss of memory, and depression, but no significant difference was recorded in the prevalences of anxiety, vertigo and dizziness. The firefighters demonstrated a more than two-fold (p<0.05) rise in plasma levels of E and NE, but the plasma DA level was relatively unchanged. Controlling age and smoking as possible confounders, firefighting was found to be associated with raised E (OR=2.15; 95% CI, 0.98-4.52), and NE levels (OR=2.24 95% CI, 1.22-3.61). In conclusion, the job of firefighting appears to be associated with stimulation of sympathetic activity and a rise in the prevalence of neurobehavioral symptoms.     

A semi-longitudinal study on physical growth of primary school children in Delhi

Summary Anthropometric measurements of weight, standing height, sitting height and circumference of head, chest, upper-arm and calf of primary school children (5–10 years) in Delhi are presented. The differences in the growth pattern of boys and girls are brought out. The growth pattern of of children in relation to different socio-economic classes is discussed. From the Survey on Morbidity and Mortality, Growth and Development and Nutritional Status of Primary School Children at Delhi, under Indian Council of Medical Research. Postal Address: Flat 32, Shankar Market, New Delhi-1.     

Mechanism of apoptosis with the involvement of calpain and caspase cascades in human malignant neuroblastoma SH-SY5Y cells exposed to flavonoids

Neuroblastoma is the most common extracranial solid tumor in children causing death at pre-school age, as no cure has yet been developed. We investigated the proteolytic mechanisms for apoptosis in human malignant (N-type) neuroblastoma SH-SY5Y cells following exposure to flavonoids such as apigenin (APG), (-)-epigallocatechin (EGC), (-)-epigallocatechin-3-gallate (EGCG) and genistein (GST). We found decrease in viability of SH-SY5Y cells with an increase in dose of APG, EGC, EGCG and GST. Predominantly apoptosis occurred following exposure of SH-SY5Y cells to 50 microM APG, 50 microM EGC, 50 microM EGCG and 100 microM GST for 24 hr. Apoptosis was associated with increases in intracellular free [Ca(2+)] and Bax:Bcl-2 ratio, mitochondrial release of cytochrome c and activation of caspase-9, calpain and caspase-3. Induction of apoptosis with APG and GST showed activation of caspase-12 as well. Activation of caspase-3 could cleave the inhibitor-of-caspase-activated DNase (ICAD) to release and translocate caspase-3-activated DNase (CAD) to the nucleus. Activation of caspase-8 cleaved Bid to truncated Bid (tBid) in cells treated with EGC and EGCG. EGC and EGCG induced apoptosis with caspase-8 activation and mitochondria-mediated pathway, whereas APG and GST caused apoptosis via an increase in intracellular free [Ca(2+)] with calpain activation and mitochondria-mediated pathway. Activation of different proteases for cell death was confirmed using caspase-8 inhibitor II, calpeptin (calpain inhibitor), caspase-9 inhibitor I and caspase-3 inhibitor IV. Thus, plant-derived flavonoids cause cell death with activation of proteolytic activities of calpain and caspases in SH-SY5Y cells, and therefore serve as potential therapeutic agents for controlling the growth of neuroblastoma.     

A longitudinal study on physical growth of children of different birth weight groups from birth to 5 years

Summary A statistical analysis of the physical growth of 1858 children of different birth weight groups in an urban community of Delhi, during the age period from birth to 5 years, is presented. The relative growth pattern of weight, height, head and chest circumferences is discussed. The literature related to the subject is briefly reviewed. From the Longitudinal Morbidity and tality Survey of Children Unit, Indian Council Medical Research, Postal Address: Flat 32, mkar Market, New Delhi-1.