Topical amiloride solution accelerates healing of mechanical skin ulcers in albino rats

The present investigation was undertaken to explore the ulcer healing properties of three dosage schedules of various concentrations of topically administered amiloride solution in mechanically produced skin ulcers in albino rats. Four skin ulcers (two on either side of the midline) were made 2.5 cm apart on the preshaved back of each anesthetized rat with a round body skin biopsy punch (7 mm diameter) through the dermis to the depth of subcutaneous tissue. The animals were randomly divided into groups of 5 rats each. Ulcers on one side of the midline were treated with normal saline and served as control, whereas those on the other side were treated with amiloride solutions. Each ulcer was observed for its size, slough formation and any sign of irritation on alternate days until healing was complete. Healing of ulcers was significantly accelerated with all the strengths of amiloride (0.01, 0.02 and 0.04%) in all the dosage schedules (o.d., b.i.d. and q.i.d.) in terms of days required for complete healing, ulcer size and area under the size-time curve. This acceleration was dose-dependent with maximum effect at b.i.d. administration of 0.04% solution. No irritation or suppression of immunity was noticeable. Thus topical amiloride may prove to be an inexpensive and better ulcer healing agent with no apparent side effects. Inhibition of u-PA by amiloride seems to be responsible for this effect.

Aging and DNA polymerase alpha: modulation by dietary restriction

Aging is an inevitable characteristic of biological processes in living organisms. For the last several years, investigators have proposed numerous mechanisms to explain the basic understanding of aging and its intervention and have provided many insights into the molecular bases and the biological events that contribute to the progressive decline in function observed during cellular aging. It is probable that a number of interacting factors, such as increased somatic mutations, changes in genetic expression, and decreased efficiency of protein synthesis, may contribute to the age-dependent deterioration of physiological processes. One cellular function involved in all of the above factors is that of normal DNA synthesis required for maintaining genomic integrity. This suggests that changes in function of DNA replicative enzymes are almost certain to be a factor in one or more of the negative cellular phenomena associated with aging. This is a particularly attractive hypothesis, since the accumulation of inactive or error-prone DNA polymerases during aging would be expected to initiate a sequence of events leading to synthesis of altered proteins and the general dysfunction of a wide range of cellular processes. Dietary restriction is the only anti-aging regimen uniquely suited to identifying these cellular processes and could play a significant role in maintaining cellular mechanisms necessary to reduce the rate at which mutations accumulate during aging. The observation that dietary restriction may impede the age-related decline in the activity and fidelity of DNA polymerases and in the decline of repair DNA synthesis, suggests potential mechanisms by which dietary restriction could extend the lifespan of animals, including humans.

Toxic effect of synthetic pyrethroid permethrin on the enzyme system of the freshwater fish Channa striatus

Treatment with 40% and 80% of the LC50 (24h) of the pyrethroid permethrin after 24h exposure causes significant reduction in the activity of lactate dehydrogenase and cytochrome oxidase and enhanced the succinate dehydrogenase activity in the tissues of the freshwater fish Channa striatus. The results indicate that permethrin blocks aerobic as well as anaerobic metabolism in the exposed fishes.

Detection of mycobacterial antigen in circulating immune complexes in patients with childhood tuberculosis

The presence of both components (antigen and antibody) in circulating immune complexes (CIC) were detected in tuberculosis in children. Fifty two patients with pulmonary and extrapulmonary tuberculosis showed the presence of either components or both. CIC--antigen was present in 92.3% (48/52) and CIC antibody in 88.96% (46,52). Out of these 52 patients, 20 were proved cases, CIC antigen (ag) and CIC--antibody (ab) were present in 100% (20/20). In the control group both CIC-ag and CIC-ab and CIC = ab can be taken as an additional marker in diagnosis of tuberculosis.

Effects of ethanol on intraovarian nitric oxide production in the prepubertal rat

Nitric oxide (NO) has been shown to contribute to ovarian development and function. In non-ovarian tissues NO can be altered by ethanol (ETOH), a drug considered to be a gonadal toxin in men as well as male and female rats. The present study was undertaken to determine if some of the detrimental effects of chronic ETOH exposure on prepubertal ovarian function could be due to ETOH-induced alterations in the intraovarian NO system. Rats were implanted with intragastric cannulae on day 24 and began receiving control or ETOH diets on day 29. All rats were killed on day 34, determined to be in the late juvenile stage of development, and their ovaries and blood were collected. We analyzed the expression of the two constitutive forms of nitric oxide synthase (NOS), i.e. neuronal (n) NOS and endothelial (e) NOS, as well as the inducible (i) form of NOS protein in the ovaries of control and ETOH-treated rats by Western immunoblotting. Results demonstrate that eNOS protein increased markedly (P<0.02; 140 kDa) in ETOH-treated rats compared with controls. ETOH treatment did not alter the protein expression of nNOS (155 kDa) and only slightly increased that of iNOS (130 kDa). We also assessed NOS activity as determined by nitrite accumulation and by the conversion of L-[14C]arginine to L-[14C]citrulline. In this regard, the ETOH-treated animals showed an increase in ovarian nitrite generation (P<0.05), as well as an increase in ovarian citrulline formation (P<0.0001), when compared with control animals. Along with the above described ETOH-induced increases in ovarian eNOS and NO activity, the serum levels of estradiol were concomitantly suppressed (P<0.001) in the ETOH-treated rats. These results demonstrate for the first time the ETOH-induced changes in the prepubertal ovarian NO/NOS system, and suggest that these alterations contribute to the detrimental actions of the drug on prepubertal ovarian development and function.

Effects of ethanol on the intraovarian insulin-like growth factor-1 system in the prepubertal rat

Insulin-like growth factor-1 (IGF-1) is considered to play an important role during ovarian development and function. Because ethanol (ETOH) is a gonadal toxin in men, as well as male and female rats, we hypothesized that this drug may be having detrimental effects in the ovary by altering the intraovarian actions of IGF-1. In support of this notion, the present study was undertaken to examine the chronic effects of ETOH on the ovarian IGF-1 system in prepubertal female rats. Each rat was implanted with a gastric cannula on day 24 and began receiving either a control or ETOH liquid diet on day 29. The animals were killed on day 34, confirmed to be in the late juvenile stage of development, and their ovaries and blood were collected. Using an RNase protection assay, we determined the expression of mRNAs encoding IGF-1 and the Type 1 IGF receptor in the ovaries of control and ETOH-treated rats. Results indicate that the ETOH-treated rats showed an increase in the ovarian expression of IGF-1a (p < 0.0001) and IGF-1b (p < 0.001) mRNA, the two alternatively spliced forms of the IGF-1 gene. Conversely, ovarian IGF-1 protein levels were depressed (p < 0.05) in ETOH-treated rats as determined by radioimmunoassay. Furthermore, ETOH-treated rats showed a decrease (p < 0.01) in the expression of Type-1 IGF receptor mRNA with a subsequent decrease (p < 0.05) in the ovarian levels of IGF-1 receptor protein, as determined by Western blot analysis. Also, using Western immunoblotting, we determined increases in immunoreactive IGF-binding proteins-3 (p < 0.05) and 5 (p < 0.01), but not 4, in ETOH-treated rats as compared with controls. Furthermore, we observed a concomitant decrease (p < 0.01) in the serum levels of estradiol. These results demonstrate for the first time that chronic ETOH administration is capable of altering the prepubertal intraovarian IGF-1 signaling system. We suggest that, at least in part, these effects contribute to altered prepubertal ovarian function after chronic exposure to ETOH.

Synthesis and anti-inflammatory activity of some potential cyclic phenothiazines

Some new schiff's bases (IVa-IVe), thiazolidinones (Va-Ve), delta 2-triazolines (VIa-VIe) and formazans (VIIa-VIIe) of 2-chlorophenothiazine have been synthesized and screened against Carrageenin induced oedema in albino rats. Some compounds of the series have shown promising activity. The most active compound is 2-chloro-10[5-(2-fluorophenyl-2-oxo-4 thiazolidin-1-yl)-amino acetyl] phenothiazine was found to be most potent. This compound (Vb) was further evaluated in detail and compared with phenylbutazone for its relative anti inflammatory potency (ED50), ulcerogenic liabilities (UD50) and acute toxicity (ALD50). It was found to be almost comparable to phenylbutazone as regards anti-inflammatory activity was concerned but and minimum ulcerogenic liability and cardiovascular effects. Hence, it seems promising as an anti-inflammatory agent in our preliminary studies.

Benign osteoblastoma mimicking malignancy of the spine

A case of osteoblastoma of the spine in a sixty year old female is presented. These lesions usually get misdiagnosed as tuberculosis or malignancy of the spine. Salient diagnostic features have been discussed.

Biting behaviour and biting rhythm of potential Japanese encephalitis vectors in Assam

Studies on biting behaviour and biting cycles of medically important mosquitoes were carried out in Madhupur village and Tarajan tea estate of upper Assam. Collections were made off human baits outdoors and indoors and off cattle bait outdoors from August 1991 to July 1992. Human bait collections were performed using the 'stationary direct bait' technique. A total of 9,072 adult host seeking female mosquitoes representing 26 species and 5 genera were collected off baits of which 36.9% were collected off human baits and the rest from cattle. All mosquitoes were primarily zoophilic, although significant numbers were collected biting man outdoors. Biting preferences of important Japanese encephalitis (JE) vectors for man and cattle were studied using outdoor man:outdoor cattle ratio (attraction ratio = AR). Culex quinquefasciatus was attracted towards human baits the most (AR = 8.1:1), followed by Cx. bitaeniorhynchus (AR = 1.6:1) and Mansonia annulifera (AR = 1.3.1). The hourly biting activity of important JE vectors throughout the night on two bait types was also studied using three point moving averages. Hierarchical agglomerative cluster analysis was used to compare and classify mosquitoes on the basis of their similarity in biting rhythms.

Injury to anterior optic pathways

Fourteen patients with injury to the anterior optic pathways have been presented and analysed. Their clinical profile, radiological data and problems involved therein have been discussed. Since an expectant policy has been the rule so far, an attempt has been made to define the role of surgery in such cases.

Effect of arteether alpha/beta on uncomplicated falciparum malaria cases in Upper Assam

Thirty patients of uncomplicated Plasmodium falciparum malaria completed a clinical trial of arteether alpha/beta conducted in a malaria endemic tea garden of district Dibrugarh, Assam. Arteether was given intramuscularly in once a day dose of 150 mg for three consecutive days. The cure rate was 100 per cent with mean fever and parasite clearance time of 42.4 +/- 17.5 and 37.6 +/- 13.6 h respectively. Recrudescence/reinfection rate was 6.7 per cent. Palpable spleens of twenty out of twenty one cases on day 0 became non palpable within 28 days. Following the treatment, percentage of hemoglobin improved marginally with no remarkable change in total and differential leucocyte count. Arteether alpha/beta, besides being a potent and fast acting schizontocidal drug, also exhibited gametocytocidal action on P. falciparum.

Correlation between degree of protection and humoral antibody response in hamsters immunized with somatic and excretory secretory antigens of Ancylostoma ceylanicum

Correlation between the degree of protection and induced serum antibody response in hamsters immunized with somatic and excretory-secretory (ES) antigens of adult. A. ceylanicum was investigated. Hamsters were immunized with non purified and Sephadex G-200 fractions (F1, F2 and F3) of somatic and ES antigens. The degree of protection was assessed in terms of percent worm reduction compared to controls against challenge infection. Induced humoral antibody response was determined by ELISA. Both somatic and ES antigens had shown moderate to significant protection but the latter was found more immunogenic as highest level of protection (67.02%) was achieved by these antigens. Humoral antibody was found highly elevated in animals immunized with protective doses of somatic and ES antigens. The maximum serum antibody titer i.e. 1:3200 was noticed in animals immunized with high protective dose (64.59% protection) of fraction F1 of ES antigens. Antibody titer correspond to the degree of protection and a positive correlation between induced humoral antibodies and protection level was established.

Albendazole therapy in orbital cysticercosis

A patient with orbital cysticercosis is being presented, where albendazole therapy was successfully used. Serial CT scans of the lesions showed definite signs of resolution. The role of albendazole therapy in cysticercosis has been discussed. The relevant literature has been reviewed in brief.

Effects of oral lithium on the action of various C.N.S. active drugs

Effects of prolonged lithium administration was seen on the action of various psychoactive drugs in animals. Apomorphine induced pecking in pigeons increased significantly by lithium treatment for 14 days, from 1445.3 +/- 202.5 in control to 2785.8 +/- 205.8 in Gp. B. Haloperidol-induced catalepsy score in albino rats increased significantly following chronic lithium treatment compared to control. Chlorpromazine-induced hypothermia in rabbits was immediate but transient, while in lithium treated rabbits induction of hypothermia was delayed, sustained and of greater magnitude. This action of lithium may be mediated by increasing the permeability of blood-brain barrier, or enhancing the sensitivity of alpha-adrenoceptors in brain.

Role of some environmental factors in modulating seasonal abundance of potential Japanese encephalitis vectors in Assam, India

Temporal changes in the abundance of host-seeking, potential Japanese encephalitis (JE) vector mosquitos and the role of some ecological factors that are modulating the abundance of vector mosquitos were studied. Vector surveillance was conducted for one year in 4 JE prone villages of Dibrugarh, Assam. Among potential JE vectors, the most abundant mosquito was Culex vishnui s.s. comprising about 22.32%. Maximum density of the mosquito was found during the month of April and another peak was observed in the month of September. The influence of meteorological factors on the abundance of JE vectors was found to vary from species to species. The final multiple regression equations (after variables were selected using STEPWISE procedure) consisted of a combination of linear, quadratic, cubic and interactive ecological variables and accounted for 25-98% of the variations in the abundance of JE vector mosquitos. Complex interactions among environmental factors, such as minimum and maximum temperature, rainfall and flood level are involved in modulating the seasonal abundance of mosquitos. A time lag is involved before a cause and effect relationship is established between environmental parameters (independent variables) and entomological variables (dependent variables). Inundation caused by flooding is favorable for mansonioid mosquito species whereas it has an adverse effect on non-mansonioid mosquito species.

Differential expression of DNA polymerase alpha in normal and transformed human fibroblasts

The expression of DNA polymerase alpha (pol alpha) was studied in human fibroblast lines W138 (fetal lung) and GM3529 (skin, established from a 66 yr old donor), and their Simian virus 40 (SV40) large tumor antigen (TAg)-transformed corollaries, 2RA and 2-1 respectively. Both SV40-transformed and pSV3.neo (SV40-derived plasmid)-transformed cells express TAg, a virally encoded protein not expressed by the normal parent cell lines. Northern blot hybridization studies showed increased recovery of pol alpha mRNA from transformed cells compared with normal cells. This increase was correlated with increased pol alpha mRNA transcription as determined by nuclear run-on assays. Northern blot analyses also showed an increase in the instability of translationally active pol alpha mRNA in transformed cells. The results suggest that TAg, in addition to its dsDNA binding, pol alpha binding, retinoblastoma protein binding and helicase activities, may be involved either directly or indirectly in regulation of the steady state mRNA levels of pol alpha at the transcriptional level in both fetal and aged donor-derived transformed fibroblasts.

Vector incrimination in Tamulpur primary health centre, district Nalbari, lower Assam during malaria outbreak 1995

A widespread outbreak of malaria occurred in different districts of lower Assam in April, 1995. Entomological investigations were carried out in Primary Health Centre Tamulpur, the worst hit area of Nalbari district. Of the nine anopheline species collected, Anopheles minimus was incriminated as the malaria vector with sporozoite rate of 6.5 per cent. The slow moving streamlets were identified as the sole breeding places of An. minimus.

A study of spectrum of iodine deficiency disorders in rural area of Uttar Pradesh

In the present study, attempt has been made to study the spectrum of the iodine deficiency disorders (IDD) in a sub Himalayan hyperendemic area. Iodine deficiency has been found to enhance the conditions like abortion, still birth, higher infant mortality, neonatal chemical hypothyroidism, congenital anomalies, retarded growth, hypothyroidism, endemic goitre and endemic cretinism.