Drug addiction in sickle cell disease: case report

There has been widespread speculation that patients with sickle cell disease (SCD) may become drug dependent if their painful crisis is treated with narcotics. However, there has been no scientific evidence to support this assertion. Paradoxically, individuals suffering from sickle cell disease who are not adequately treated may develop an addiction to narcotics due to self-medication to treat their pain. In this article, we describe a 38-year-old African American woman who became addicted to cocaine due to self-medication of her sickle cell pain with cocaine.     

Blood volume monitoring in intermittent hemodialysis for acute renal failure

BACKGROUND: Although hypotension commonly accompanies intermittent hemodialysis for acute renal failure (ARF) in the intensive care unit (ICU), little is known about how it may be prevented. Online relative blood volume (RBV) monitoring has been used to reduce hypotension in chronic hemodialysis, but is of unproven benefit in ARF. This study tested the hypothesis that hypotension is predictable using online RBV monitoring in patients dialyzed for ARF in an ICU setting. METHODS: The primary definition of hypotension was mean arterial pressure (MAP) <70 mm Hg; systolic blood pressure (SBP) <100 mm Hg was used as a secondary outcome. Fifty-seven treatments were prospectively studied in twenty consecutive adult patients treated with intermittent hemodialysis. RBV was continuously measured using the Hemoscan device (Gambro). RESULTS: Hypotension occurred in 30% of treatments as defined by MAP, and 18% as defined by SBP. There was no evidence of patient-specific or universal RBV thresholds that were associated with hypotension. Analysis using the kappa statistic showed that concordance of RBV and hypotension (that is, RBV falling prior to hypotensive episodes rather than rising or remaining stable) was no greater than chance. RBV and rate of change in RBV slopes did not predict hypotension as a dichotomous outcome, and were not correlated with MAP or SBP whether autocorrelation was corrected for or neglected. Substituting rate of change in RBV (RBV slopes) for absolute RBV values did not improve predictive power. CONCLUSIONS: These results suggest that strategies based on online RBV monitoring are unlikely to reduce hypotension in intermittent hemodialysis for ARF that is delivered through central venous catheters.     

Sarcoidosis in India: practical issues and difficulties in diagnosis and management

Although sarcoidosis has emerged as an important lung disease in this country, clinicians continue to face difficulties in diagnosis and management of the illness. The relative rarity of sarcoidosis and the remarkable similarity of clinical, radiological and histopathological features with tuberculosis pose problems in the differential diagnosis. Although the pattern and sites of involvement do help, the prevalence of tuberculosis, including those of extrapulmonary sites, is so high that a confident exclusion of the illness is not easy. One important point of difference is the presence of tuberculin-anergy in sarcoidosis vis à vis tuberculosis. Bronchoscopic transbronchial lung biopsy is positive in over 80 percent of patients with sarcoidosis. Exclusion of tuberculosis to diagnose sarcoidosis is important in particular because corticosteroids form the mainstay of treatment for sarcoidosis. Asymptomatic patients with stage I pulmonary and other milder forms of cutaneous sarcoidosis do not need systemic steroid therapy. We have found favorable results with steroid sparing drugs such as methotrexate and azathioprine. Patients with refractory disease, relapse of illness and those with steroid induced complications or concomitant illnesses likely to be worsened by corticosteroids, are mostly treated with weekly, low-dose methotrexate.     

Absence of association between the Fc gamma receptor IIIA-176F/V polymorphism and the severity of malaria in Thai

Human Fc gamma receptor (Fc gamma R) genes form a clustered gene family, which consists of Fc gamma RIIA, IIB, IIC, IIIA, and IIIB genes, on chromosome 1q23. We previously reported that the Fc gamma RIIA-131H/H genotype in combination with the Fc gamma RIIIB-NA2 allele is associated with susceptibility to cerebral malaria, and that such an association can be caused by linkage disequilibrium (LD) between these polymorphisms and the primary associated gene(s) in this region. Fc gamma RIIIA is known to exhibit the genetic polymorphism Fc gamma RIIIA-176F/V coded for different affinity to IgG1 and IgG3. In this study, we examined a possible association between Fc gamma RIIIA-176F/V polymorphism and severity of malaria in 462 adult Thai patients with Plasmodium falciparum malaria. The frequencies of Fc gamma RIIIA-176V among patients with mild malaria, with non-cerebral severe malaria, and with cerebral malaria were 32.7%, 29.9%, and 36.3%, respectively. This polymorphism showed neither positive nor negative association with the severity of malaria. Thus, we concluded that the association of Fc gamma RIIA-131H/R and Fc gamma RIIIB-NA1/NA2 polymorphisms with cerebral malaria in Thailand is not due to the LD caused by Fc gamma RIIIA-176F/V.     

Unusual complication—VP shunt coming out per rectum and brain abscess

VP shunt is the most common pediatric neurosurgical procedure. It has been shown to result in variety of complications, which may have devastating consequences. Discussed below is one of the rare complications and the strategy to manage it successfully.     

A fundamental study of the microencapsulation procedure utilizing coacervation in a polystyrene-cyclohexane solution

Coacervation in polystyrene (PS)-cyclohexane solution induced by the lowering of temperature was utilized to investigate the fundamental problems involved in the microencapsulation procedure. Polydispersity of PS played a vital role in determining variables at the critical state of phase separation, such as the composition of coacervate (dense) and lean phases. This also depended on temperature. Observations revealed that microcapsules of glass beads consist of a wall with a thin film of PS covered with a thick shell of talc. Poor utilization of PS may limit practical applications of this system unless effective measures are taken for the recovery of unutilized PS. Controlled release behaviour from microcapsules was successfully investigated by using encapsulated anhydrous sodium sulphate (ASS) particles, and applying the Higuchi model to the estimation of the effective diffusion coefficient of ASS through the composite wall. The values of diffusion coefficient decreased from an order of 10(-7) to 10(-8) cm/s by lowering the encapsulation temperature.     

Characterization of ultraviolet light-induced relaxation of the isolated duodenum of the rat.

1 Isolated duodenum of the rat, exposed to ultraviolet (u.v.) light in the presence of NO2 ions, responded with reversible relaxation. 2 The photorelaxation response did not seem to involve any known receptor mechanisms and was independent of any ganglionic or neuronal influences. 3 Changes in the ionic environment of the tissue showed that NA+ and Ca2+ were essential for the photorelaxation. K+ depolarized-tissue did not show the photoresponse. 4 The presence of the metabolic inhibitors, iodoacetic acid, 2,4-dinitrophenol, sodium fluoride, sodium azide or potassium cyanide, abolished the photorelaxation response. 5 It is proposed that the photorelaxation of the tissue resulted from the liberation of metabolic energy following NO2 ion-dependent absorption of u.v. light energy, which in turn, interfered with the Na+ ion movement across the cell membrane.     

beta-adrenoceptor blockade with diphenylhydantoin (DPH).

Diphenylhydantoin (DPH) (20 x 10(-6) to 80 x 10(-6) M/kg) blocked the depressor responses to isoproterenol in spinal, bilaterally vagotomized and atropine pretreated cats; depressor responses to histamine were unaffected; DPH shifted the isoproterenol concentration-response curve to the right in isolated guinea pig tracheal chain preparation, isolated rabbit ileum and isolated perfused heart of frog. The results suggest that DPH has a specific beta-adrenoceptor blocking action and the blockade appears to be competitive in nature as shown by PA2 and PA10 values.