Generation studies on benthic amphipod-Quadrivisio bengalensis, Stebbing (Gammaridae) from the Kochin Estuary, Southwest coast of India.

Quadrivisio bengalensis (Stebbing Records of Indian Museum, 1, 159-161, 1907), a eurythermal (26.5-32.2 °C) and euryhaline (0.10-26.2 psu) tropical species, makes a profound contribution as a fodder organism to the benthic biomass of tropical backwaters. Studies on life span, variations in broods, fecundity, sex ratio, brooding behaviour, brood stock assessment, growth rate, antennal segments as an index of growth, moulting frequency, mortality and starvation resistance of Q. bengalensis were made for the first time under controlled laboratory conditions of 12-h photo period for 252 days on 8 pairs of specimens (male and female) collected from the field and their successive broods. The life span of females was found to be higher (maximum 220 days) than males (maximum 175 days). Number of broods varied between 5 and 15, depending on the "status of the brood" (early or late). The maximum number of juveniles in a single brood was 24 and that by a single female over the entire life span was 211. The incubation time varied between 6 and 9 days and the duration of moults (8-18 days) was found to increase with the age of the animals. Maximum growth is usually attained by the offspring arising from the 5th to 7th broods. The 4th to 7th broods were the optimal broods for the maximum number of females attaining maturity. For broods 3 to 7 of the parental set, probability of extinction (ξ) calculated on applying stochastic branching process to generation studies for the first time showed an increasing trend with number of broods while a decreasing trend for ξ for 8th and 9th broods, with least ξ for broods 5 to 7 of the 5th, 6th and 7th generations, suggesting life span and fecundity rates as functions of the "brood status" (early or late). Whether it is true with higher crustaceans remains to be explored.

Synthetic Juvenile Hormone: Induction of Sex Pheromone Production in Ips confusus.

Topical application of 25, 50, or 100 micrograms of 10,11-epoxy-farnesenic acid methyl ester in peanut oil induced male Ips confusus to produce sex pheromone in the hindgut Malpighian tubule region. Twenty-four hours aftertreatment of male beetles with 100 micrograms of hormone, their hindgut Malpighian tubule extract was more attractive to female beetles in a laboratory bioassay than was extract from males producing pheromone naturally in ponderosa pine logs.

Effects of increased lifespan on chromatin condensation in the adult male housefly.

Analysis of the chromatin condensation pattern in optic lobe nuclei from the adult male housefly has shown significant differences in males from a long lived, low activity (LA) group as compared to a short lived, high activity (HA) group. The rate of chromatin condensation in the LA group was very much less than that observed in the HA group, leaving the nuclei from the former group in a permanently lowered condensation state. Moreover, a detailed comparison of the amount and spatial distribution of a single high density chromatin component (HDC) suggests that the low activity conditions not only lowers the rate of chromatin condensation but also alters the normal program controlling this process. Linear discriminant analysis showed that a consistently higher percentage of nuclei from the LA group, as compared to the HA group, could be classified with a 1-day-old model derived from the HA group. These results are discussed with respect to environmental influences on lifespan and are compared to the response of lipofuscin accumulation in low activity male houseflies.

Stoichiometry of the aldehyde fuchsin staining reaction for proteins.

Model systems of agar films containing known concentrations of bovine serum albumin and alpha-chymotrypsinogen were stained with aldehyde fuchsin after oxidation with acidified permanganate solution. These films were scanned in a scanning microphotometer to determine the mean extinction and the total extinction of predetermined areas. Results indicate that the dye binds quantitatively to the proteins. Blocking the acidic side groups of the proteins inhibited the binding of the dye. The degree of inhibition was directly related to the number of sulfhydryl or carboxyl groups that were blocked. Similar blocking reactions performed on the type "A" neurosecretory cells of the pars intercerebralis of the insect Oncopeltus fasciatus gave similar results. Analysis of the dye protein complexes gave a dye to acidic group ratio of 1:1.

Age-related chromatin condensation in flight muscle nuclei of the adult male housefly, Musca domestica.

Computer analysis of indirect flight muscle nuclei from the adult male housefly, M. domestica, has shown significant change with age in the chromatin condensation pattern. The pattern was analyzed by examining low, medium, and high density chromatin components (LDC, MDC, HDC). No significant change occurred in HDC with age, and the amount and distribution of LDC and MDC remain relatively stable between Day 1 and Day 4 post-eclosion. However, the analysis showed a significant increase in the amount of MDC with a corresponding decrease in the amount of LDC between Day 4 and Day 14. This exchange was accompanied by a significant redistribution of both components. These results are discussed with reference to the biochemical and ultrastructural profile of the flight muscle with age, and to age-related changes in the condensation pattern of specific brain and Malpighian tubule nuclei described earlier.

False aneurysm of the ascending aorta after surgery for Marfan's syndrome. Report of a case and review of the literature.

A case is described in which false aneurysm of the ascending aorta developed following corrective surgery for Marfan's syndrome. During the initial procedure, a dissecting aortic aneurysm and incompetent aortic valve were managed by replacing the valve with a Starr-Edwards prosthesis and the ascending aorta with a woven Dacron aortic prosthesis. Two years later the operation was repeated with the use of antibiotic cover, because the patient developed a paraprosthetic leak following subacute bacterial endocarditis with Staphylococcus aureus. The woman remained well for 6 months, after which she developed a false aneurysm of the ascending aorta and aortic incompetence which necessitated repeating the operation for a third time. The patient remains well one year later. Relevant literature available on false aneurysm of the ascending aorta is also reviewed.

Direct evaluation of mitral valve function during surgery following conservative procedures.

A method is described whereby mitral valve function can be tested during cardiopulmonary bypass under physiological conditions. This method avoids the risk of systemic air embolism during testing and can be used even in the presence of aortic regurgitation. Monitoring left ventricular pressure simultaneously with aortic root pressure prevents any overdistention of the left ventricle. This method has been in use at Guy's Hospital since 1970 and has been satisfactory and safe.

Idiopathic main pulmonary artery aneurysm.

Main pulmonary artery aneurysms with no underlying pathology are very rare, and the role of surgery in this entity is not well defined. We report our experience of one case.

Arterial switch operation: successful bilateral internal thoracic artery grafting.

Internal thoracic artery grafting in arterial switch operations for transposition of great arteries has been reported for salvage of myocardial ischemia after initial coronary transfer. We report a situation where we opted for primary coronary bypass grafting to avoid an obviously difficult coronary transfer, with successful outcome.

Transantral ligation of the internal maxillary artery.

Transantral internal maxillary ligation for epistaxis is becoming more and more popular. The intention of this paper is to bring home three points: 1. only the arterial trunk need be ligated to obtain the anticipated results, 2. by following certain guidelines the operating time can be cut down by at least 45 minutes, and 3. if the procedure is carried out in time, it can be cost-effective. As time goes on, more and more patients will be added to this analysis and eventually reported.

Carotid vascular pain--a simple treatment.

Carotid vascular pain has been misdiagnosed in the past as various other conditions. Various etiologies have been assigned to it without clinical or experimental evidence. Haphazard treatment using ganglion-blockers, nicotinic acid, allergy hyposensitization and steroids have been instituted based on imaginary causes of the problem. This paper intends to show that there is no known cause for carotid pain. A simple, effective, safe and inexpensive form of treatment is presented; namely, explaining the problem to the patient, allaying their apprehension and using aspirin in a more scientific fashion. A three-year follow-up is presented.

Clinical trial of diaminodiphenylsulfone (DDS) in nasal and nasopharyngeal rhinosporidiosis.

Rhinosporidiosis is a fairly common problem for the Otolaryngologist in many parts of the world, because of its prompt recurrence after surgical excision. Though not a fatal disease, it inflicts various kinds of social and economic strain on the patients and their families. No medical treatment has been found to be effective in controlling rhinosporidiosis. Such drugs as griseofulvin and amphotericin have been tried without much benefit. In this clinical trial with dapsone on 32 patients (71.4%) did not have recurrence in a three year period and none of them needed surgery in that period. Thirty-two patients were used as controls, and 93% of them needed surgery for recurrent rhinosporidiosis in the same three year period. Dapsone (diaminodiphenylsulfone) is a relatively safe drug to use, and no major side effects were noticed in this trial.

Unusual migration of a Kirschner wire.

Orthopaedic procedures involve utilization of internal fixation devices. Screws, wires and plates are removed due to loosening or infection. Migration of these devices is also well established. We present an unusual case of migration of a Kirschner wire from the right shoulder to the spleen within a period of 12 h. Review of the literature does not reveal any previous occurrence of this nature.

Unusual variant of pulmonary arteriovenous communication.

We report a case of direct communication of right pulmonary artery to left atrium , a very rare congenital anomaly treated surgically with complete success at our centre.

Coronary artery aneurysm.

A 55 year old man presented with a 2 year history of angina of effort complicated by two myocardial infarctions. Coronary angiography confirmed fusiform aneurysm of the right coronary artery and disease of the left anterior descending coronary artery. The patient underwent surgery with exclusion of the right coronary artery aneurysm and reversed saphenous vein graft, and graft to the left anterior descending coronary artery, with uneventful recovery. The clinical and radiological features are reviewed, and the surgical options considered.

Surgical removal of intracardiac foreign bodies.

When non-surgical methods for removing intracardiac foreign body have failed, surgical removal should be attempted. Two patients who had dislodged ventriculoatrial shunts for hydrocephalus underwent open removal of catheters, one from the pulmonary artery while the other from the right atrium. Both were successfully retrieved without cardiopulmonary bypass. We describe the clinical and radiological features, with a review of the indications and techniques available.

Giant left ventricular aneurysm.

A 65 year old lady with known inferior left ventricular aneurysm presented with acute dysphagia and hoarseness. A barium swallow examination confirmed extrinsic compression of the oesophagus. Successful aneurysmectomy resulted in complete relief of the dysphagia and hoarseness. The clinical and radiological features are reviewed.

Effects of eyestalk ablation on moulting and growth of penaeid prawn Metapenaeus dobsoni (de Man).

Penaeid prawns M. dobsoni of two different size ranges were ablated both unilaterally (UEA) and bilaterally (BEA) and subjected to individual study. The UEA prawns consumed almost the same amount of food as the control prawns in the size group, 35-40mm, but consumed about 57.8% more food than the control prawns in the larger size group, 48-53mm. Growth was estimated as length and weight changes and significant variation was observed. The moult rate and dry moult weight showed marked differences. Average intermoult period increases with second ablation. Dry weight of moult in every succeeding moult was found to decrease irrespective of the level of ablation. Unilateral eyestalk ablation resulted in increase in dry weight whereas bilateral eyestalk ablation reduced the dry weight of moult and this decrease in the rate increased after each subsequent moult. In the larger size group, values of protein efficiency ratio (PER) were almost same as that of the lower size group. The UEA prawns exhibited highest conversion efficiency. The production rate of UEA prawns was 84% more than that of the control whereas BEA prawns indicated negative production. The same trend followed for net growth efficiency also. The results suggest that unilateral eyestalk ablation can be resorted to accelerate growth and conversion efficiency. Eyestalk ablation has been frequently resorted in matured forms for inducing maturation of gonads. For the first time attempts have been made to compare between the effects of removing one eyestalk versus two and changes taking place in juvenile forms especially in their physiology related to growth.