Attenuation of intracavitary applicators in 192Ir-HDR brachytherapy

Unlike the penetrating monoenergetic 662 keV gamma rays emitted by 137Cs LDR sources, the spectrum of 192Ir used in HDR brachytherapy contains low-energy components. Since these are selectively absorbed by the high-atomic number materials of which intracavitary applicators are made, the traditional neglect of applicator attenuation can lead to appreciable dose errors. We investigated the attenuation effects of a uterine applicator, and of a set of commonly used vaginal cylinders. The uterine applicator consists of a stainless steel source guide tube with a wall thickness of 0.5 mm and a density of 8.02 g/cm3, whereas the vaginal cylinders consist of the same stainless steel tube plus concentric polysulfone cylinders with a radius of 1 or 2 cm and a density of 1.40 g/cm3. Monte Carlo simulations were performed to compute dose distributions for a bare 192Ir-HDR source, and for the same source located within the applicators. Relative measurements of applicator attenuation using ion-chambers (0.125 cm3) confirmed the Monte Carlo results within 0.5%. We found that the neglect of the applicator attenuation overestimates the dose along the transverse plane by up to 3.5%. At oblique angles, the longer photon path within applicators worsens the error. We defined attenuation-corrected radial dose and anisotropy functions, and applied them to a treatment having multiple dwell positions inside a vaginal cylinder.     

Effects of interferon in malaria infection

Earlier, we reported that prophylactic treatment with human interferon gamma (rHuIFN-gamma) protected monkeys against Plasmodium cynomolgi B malaria infection. We have tested the efficacy of rHuIFN-gamma on relapsing stage of experimental P. cynomolgi B malaria infection in rhesus monkeys. No effect of rHuIFN-gamma was seen against experimental relapsing stage compared with controls; however, it appears that chloroquine (CHL) may have interfered with the antimalarial effect of IFN, since treatment with CHL inhibits the antiviral activity of mouse alpha/beta IFN and polyinosinic-polycytidylic acid (poly I:C) against Semliki forest virus (SFV) in mice. These results may have clinical implications especially with the use of IFN against virus infection, cancer and in parasitic infections in malaria endemic areas where CHL is one of the most widely used antimalarial drugs. Our result also shows that CHL treatment enhances the virus replication in mice and suggest a possible connection between AIDS and malaria infection, since the spread of AIDS has been rapid in parts of tropical Africa that have a high incidence of malaria, and chloroquine has been frequently used in the chemotherapy of malaria.     

Leukocyte-reduced transfusions in cardiac surgery results of an implementation trial

An implementation trial of leukocyte-reduced transfusions in cardiac surgery (primary coronary artery bypass graft and valve replacement) was performed from July to December 1998; comparisons were made with data from the same period in 1997. Patients from both periods were similar in important preoperative and intraoperative variables (age, sex, weight, number of units of RBCs transfused, ejection fraction). The mean total number of complications was statistically significantly decreasedfrom 0.26 complications per patient in the non-leukocyte-reduced to 0.19 in the leukocyte-reduced recipients. Overall, the mean +/- ISD costs of care per patient decreasedfrom 1997 ($27,615 +/- $33,973) to 1998 ($27,038 +/- $24,107). Mean costs decreased $1,700 per patient for recipients of leukocyte-reduced blood in 1998 compared with recipients of non-leukocyte-reduced blood in 1997 Mean costs increased $4,000 per patient in patients who did not receive transfusions in 1998 compared with 1997. Hospitalization costs decreased when leukocyte-reduced transfusions were implemented for patients undergoing cardiac surgery in our institution. Implementation of leukocyte reduction may be cost neutral or cost saving in at least some settings.     

Complete Nucleotide Sequence Analysis of a Western Pacific Dengue-1 Virus Strain

We have determined the complete nucleotide sequence and the deduced amino acid polypeptide sequence of the genome of a dengue-1 (DEN-1) virus strain isolated from a patient on Nauru in the Western Pacific in 1974 (West Pac 74). The complete genome is 10,735 nucleotides in length and contains a single long open reading frame of 10,176 nucleotides encoding a polyprotein of 3392 amino acids. When compared to DEN-1 Singapore S275/90, the nucleotide and amino acid sequence homology are 94% and 97.8%, respectively. This revised version was published online in July 2006 with corrections to the Cover Date.     

Cardiopulmonary resuscitation in hospitalized patients: continuing problems of decision-making

Disturbingly low survival rates after CPR prompted us to carry out a series of studies. Of 272 patients receiving CPR at our 600-bed community hospital in 1984, 102 (37.5%) patients survived initial resuscitation and 30 (11%) survived their hospitalization. Of the 102 initial survivors, only 15 patients had received full CPR including cardiac compression and/or defibrillation, endotracheal intubation, and cardiotonic drugs. These data were compared with those for 129 patients admitted to our critical care units in 1982 and 1983 in whom CPR was withheld. These patients had been designated "No CPR" primarily because of their poor response to therapy. There was an 11% survival rate for patients who had received CPR compared to a 16% survival rate for the "No CPR" group. These data suggest that criteria for administering CPR to hospitalized patients should be improved.     

India's needs and priorities in fertility regulation research

This article evaluates the needs and priorities of India in fertility regulation research. There are multivariate factors that affect the perceptions of people about fertility regulation in India. The socioeconomic status, level of education and religious beliefs have strong influences on their decision on the family size, spacing between children and also the sex of the children. Moreover, a large number of people are either quite ignorant of or cannot afford to avail with the technologies and services for controlling their fertility. These factors generally perpetuate high fertility, which strongly affect the infant and maternal mortality, and eventually the quality of life both for the present and the future generation. The International Conference on Population and Development Program of Action has provided India with an alternative to develop newer methods of fertility regulation so as to widen contraceptive choices. The objective of research in fertility regulation should ensure the fertility control of couples and ability to plan the number and spacing of children. Research in fertility regulation should be aimed at expanding contraceptive choices by improving the accessibility and acceptability of good quality contraceptive products and services. It would necessitate: improving the quality of care; increasing awareness about sexuality and fertility regulation; empowering women; and increasing male-female partnership in sharing responsibilities for family planning and parenthood.     

Management of ocular perforations resulting from peribulbar anaesthesia

PURPOSE: To analyze the clinical presentation and outcome of treatment for globe perforation secondary to peri-bulbar anaesthesia. METHODS: Eight patients (3 females and 5 males) aged 66-84 years were included in the study. Ocular perforations were suspected in 3 cases before or during surgery, in 4 cases diagnosis was established within one week and in one case at 3 weeks. Three patients underwent indirect argon laser photocoagulation to seal the retinal break, one patient had cryotherapy, 3 patients underwent a pars plana vitrectomy with fluid gas exchange and endo-laser; and one patient refused any further treatment. RESULTS: The final visual acuity after a mean follow up of 14 months was better than 6/9 in 2 patients, between 6/9-6/12 in 4 patients, and perception of light in 2 patients. CONCLUSION: If diagnosed early and treated adequately, a majority of patients with globe perforation during periocular anaesthetic could be saved.     

Hamartoma of the Face

Hamartomas are tumour like malformations which are due to a developmental anomaly. They are most commonly seen in the spleen, lungs, liver and kidney, they are rare in the head and neck region. A rare case of Hamartoma of the soft tissues of the face in a 13 year old boy is reported.