Expression and immunohistochemical localisation of the G[beta gamma]-activated and calcineurin-inhibited adenylyl cyclase isoforms in rat articular chondrocytes

Objective: to determine the expression and localisation of the G[beta gamma]-activated adenylyl cyclase [AC] isoforms 2, 4, and 7 and calcineurin-inhibited AC isoform 9 in rat articular chondrocytes

Study Design: experimental study

Place and Duration of Study: Jumma Research Laboratory and Histology Laboratory, The Aga Khan University, Karachi, from 2009 to 2011

Methodology: fresh slices of articular cartilage were taken from various synovial joints of rats of different age groups. The expression of AC isoforms was determined by RT-PCR and immunohistochemistry was performed to localise these isoforms in articular chondrocytes. Tissue sections were processed for immunostaining with respective antibodies. The color was developed by diaminobenzidine

Results: all the studied AC isoforms were found to be differentially expressed in different zones of the rat articular cartilage. Generally, expression of all AC isoforms studied increased with age. The expression of the AC isoforms through PCR was almost consistent with the localisation of these isoforms by immunohistochemistry

Conclusion: these data add to the information about signalling cascades possibly involved in articular chondrocytes. Variable expression of AC isoforms 2, 4, 7, and 9 suggest a role for the signalling cascades regulated by the AC isoforms in articular chondrocytes

Lactose intolerance in infants in Faisalabad region

Lactose tolerance tests were done on 30 infants. Lactose, lg/kg body weight, was given to each infant orally. Heal capillary blood samples were taken at 0, 30, 60 and 90 minutes and blood glucose and galactose were estimated. An increase in blood glucose and galactose of at lease 20 mg percent was the criteria for Lactose tolerance. Intolerance of lactose was observed in 4 out of 11 female infants below six months while 5 out of 5 females infants above six months were intolerant to lactose. Out of 14 male infants, none below six months were intolerant to lactose. There was a significant increase in the percentage of intolerance of lactose after six months of age. It was concluded from this study that lactose intolerance is common in Faisalabad area and is quite common in female infants and increases with age

Lactose intolerance in Pakistani adults

To study the prevalence of lactose intolerance, oral lactose tolerance tests and glucose-galactose tolerance tests were conducted on 50 adults. On the first day, lactose [1 g per kg body weight] and on next day 1/2 g glucose and 1/2 g galactose mixture was administered to same individual. Finger tip capillary blood sample were taken on each day at 0, 30, 60, 90 and 120 minutes after the administration of lactose or glucose galactose mixture to estimate blood glucose and galactose levels. Intolerance of lactose was observed in 9 out of 26 males [34.61%] and 13 out of 24 females [54.16%]. The overall prevalence was 44 percent. The prevalence of lactose intolerance among males aged 15 to 35, 36 to 55 and 56 to 75 years was 25%, 2 1.43%, 100% whereas the corresponding figures for females were 44.45, 58.33, 66.66 percent. This study revealed that prevalence of lactose intolerance was high among females as compared to males

Protective role of compensatory growth in the development of mammalian inner ear

The inner ear in rats is ectodermally derived. It appears as a placode on day 8 of a 22-day gestational period. In the developing inner ear most of the cells undergo terminal mitosis between gestational days 13 and 15. During this critical period of development exposure to toxic substances may result in malformations of the adult inner ear. To test this hypothesis, rat fetuses were exposed to 5-fluoro-2' -deoxyuridine [FUdR], an antimitotic substance, on gestational days 12-16. The animals also received one injection of 3H-thymidine 1 h prior to autopsy. The inner ear specimens were prepared for morphological observations and biochemical assays. Four hours after the administration of FUdR there was a substantial decrease in the number of otic cells. This trend was seen until 24 h after treatment. When examined on day 21 of gestation, the inner ears from the fetuses exposed to FUdR during gestational days 12-15 almost completely recovered from the toxic effects of the drug. The phenomenon of compensatory growth observed during embryonic development may represent an important protective feature. During early stages of organogenesis, the otocyst perhaps has a remarkable capacity for recovery resulting in relatively fewer congenital anomalies of the inner ear