Anti‐malarial drug effects on parasite dynamics in vivax malaria

Relapses of Plasmodium vivax malaria are prevented by 8-aminoquinolines. If hypnozoites survive, then the subsequent blood stage infections in early relapses (< 2 months) are suppressed by the slowly eliminated anti-malarial drugs used to treat the blood stage infection (chloroquine, artemisinin combination treatments), but they are not usually eliminated. The 8-aminoquinolines have significant blood stage activity which contributes to therapeutic responses. The latent interval from primary infection to early relapse depends on the number of activatable hypnozoites, the dose of anti-malarial, its pharmacokinetic properties, the level of resistance (minimum inhibitory concentration) and immunity. The dose–response relationship for radical curative efficacy of primaquine and tafenoquine is steep over the total dose range from 1.5 to 5 mg base/kg which may explain the poor efficacy of tafenoquine at the currently recommended dose.

Birth Weights of the Babies in Diabetic Pregnancies

As the problem of diabetes is gradually increasing day by day, large babies of diabetic mothers are also becoming an alarming health problem. The shadow of diabetes falls on the pregnant women as long as fifteen or twenty years before the disease declares itself by glycosuria and hyperglycaemia. The latent interval between the birth of a large baby and the development of clinical diabetes may range up to 40 years, and the average as 24 years. During this period of prediabetics the mother may give birth to a series of large babies in her pregnancies. Pregnancy constitutes one of the few physiologic events that unmask the diabetic propensities. Excess fetal weight over 4 kg is regarded as fetal macrosomia and is due to fetal hyperglycemia; fetal pancreatic beta cell hyperplasia-foetal hyperinsullnism, deposition of fat and glycogen in foetus. Adequate control of diabetes with the preconception and prenatal care is the sheet anchor to prevent fetal macrosomia which occurs in 20-60% cases of gestational and clinical diabetes.TAJ 2009; 22(1): 311-314

Impact on the quality of life of patients with arteriovenous malformations during the latent interval between gamma knife radiosurgery and lesion obliteration

Object. The aim of this study was to measure the quality of life (QOL) in patients with cerebral arteriovenous malformations (AVMs) receiving gamma knife treatment before total AVM obliteration. Quality of life was assessed as it related to the knowledge of rebleeding risk during the waiting period, AVM symptoms, and previous bleeding. Methods. Thirty-nine patients age 18 years or older without other medical problems were asked to complete a questionnaire that included demographic variables, immediate effect of gamma knife radiosurgery, symptoms of AVM, previous hemorrhage, and the Duke—University of North Carolina Health Profile (63 items). Conclusions. The QOL of patients with cerebral AVM during the waiting period after undergoing gamma knife treatment was affected by irreversible physical disabilities rather than the knowledge of hemorrhage risk and bleeding experience.

Evaluation of gamma thalamotomy for parkinsonian and other tremors: survival of neurons adjacent to the thalamic lesion after gamma thalamotomy

Object. The effects of gamma thalamotomy for parkinsonian and other kinds of tremor were evaluated. Methods. Thirty-six thalamotomies were performed in 31 patients by using a 4-mm collimator. The maximum dose was 150 Gy in the initial six cases, which was reduced to 130 Gy thereafter. The longest follow-up period was 6 years. The target was determined on T2-weighted and proton magnetic resonance (MR) images. The point chosen was in the lateral-most part of the thalamic ventralis intermedius nucleus. This is in keeping with open thalamotomy as practiced at the authors' institution. In 15 cases, gamma thalamotomy was the first surgical procedure. In other cases, previous therapeutic or vascular lesions were visible to facilitate targeting. Two types of tissue reaction were onserved on MR imaging: a simple oval shape and a complex irregular shape. Neither of these changes affected the clinical course. In the majority of cases, the tremor subsided after a latent interval of approximately 1 year after irradiation. The earliest response was demonstrated at 3 months. In five cases the tremor remained. In four of these cases, a second radiation session was administered. One of these four patients as well as another patient with an unsatisfactory result underwent open thalamotomy with microrecording. In both cases, depth recording adjacent to the necrotic area revealed normal neuronal activity, including the rhythmic discharge of tremor. Minor coagulation was performed and resulted in immediate and complete arrest of the remaining tremor. Conclusions. Gamma thalamotomy for Parkinson's disease seems to be an alternative useful method in selected cases.

Hand-Arm Vibration Syndrome Associated with Impact Vibration

The data from 141 hand-arm vibration exposed workers examined for hand-arm vibration syndrome (HAVS) was analyzed in a Cox regression model to determine whether smoking, alcohol, the use of gloves, duration of weighted vibration exposure, and vibration impulsiveness affected the rate of onset of Raynaud's phenomenon. The results show that workers with HAVS were more likely to be smokers. No association with alcohol was detected, but none of the men were heavy drinkers. While weighted acceleration levels affected the latent interval for finger blanching, the strongest association was with impulsiveness from high-level impact pneumatic tools (identified by a 20 dB or more difference between the weighted Leq component and the corresponding weighted peak acceleration in the dominant direction). This association had only been recognised previously in pedestal grinders, so its recognition in multiple hand tools has important implications for prevention methodology development and standard setting. The use of gloves was found to reduce the risk from high-level impact pneumatic tools.

The involvement of oestrogen in the development and progression of breast disease: epidemiological evidence

SynopsisThe epidemiological approach to the investigation of breast cancer is briefly described with special reference to case-control and cohort studies. Risk factors for breast cancer are then reviewed, paying particular attention to menstrual and reproductive factors and to body weight. Some of the hypotheses which attempt to draw the epidemiological observations together are also outlined.The effects of exposure to exogenous oestrogens are considered in more detail. There is evidence from one study that the administration of large doses of stilboestrol during pregnancy increases breast cancer risk after a latent interval of about twenty years. Conjugated equine oestrogens administered to postmenopausal women may also slightly increase breast cancer risk after prolonged use. Little information is available about the effects of any other type of “hormone replacement therapy”. Combined oral contraceptives do not appear to have any general effect on breast cancer risk, but prolonged early use, especially use before first term pregnancy, may be harmful to the breast.

Routine Daily Surveillance Cultures in the Management of C.A.P.D. Patients

The authors collected 3876 daily specimens of dialysate for bacteriological culture from II patients on CAPD over a period of 155 patient treatment months. During the trial period, there were 30-culture positive episodes of peritonitis. In 16 ( 530;”) of the episodes there was a latent interval of 72 hours or less between the presence of organisms in the dialysate and the clinical onset of peritonitis. However, 153 positive cultures were unrelated to ari episode of peritonitis. Most asymptomatic positive cultures, therefore, do not progress to peritonitis. There were eight episodes of “recurrent” peritonitis. In six of these, although initially the dialysate was rendered sterile and the patient asymptomatic by antibiotics the pathogenic organism was isolated again from dialysate on more than one occasion, during continued antibiotic administration. In six of these cases, a second episode of peritonitis due to the same organism recurred within 20 days of discontinuing antibiotics suggesting that most episodes of “recurrent” peritonitis represent treatment failure, rather than reinfection.