Abuse of inhalants: a review

Inhalants, a chemically heterogeneous group of psychoactive substances found in adhesives, lighter fluids, spray paints, cleaning fluids and typewriter correction fluid, may be used by up to 10% of young people. This article reviews the health effects, epidemiology, risk of other substance use and addiction and psychiatric co-morbidity associated with the practice of inhalant use.     

Phencyclidine- and diazepam-like discriminative stimulus effects of inhalants in mice.

It has been shown that abused solvents, such as 1,1,1-trichloroethane (TCE) and toluene, share certain pharmacological properties with central nervous system depressants, such as alcohol and anesthetic vapors. Several vapors were tested for diazepam (DZ)- and phencyclidine (PCP)-like discriminative stimulus effects to further explore their pharmacological specificity. In DZ-trained mice, methoxyflurane fully substituted, and TCE produced partial substitution. Flurothyl and toluene produced no appreciable DZ-lever responding at any concentration tested. On the other hand, toluene produced concentration-related partial substitution for PCP, whereas methoxyflurane, TCE, and flurothyl did not substitute. The substitution of some of these vapors for DZ or PCP suggests that, like ethanol, the discriminative stimulus effects of abused solvents partially overlap those of N-methyl-{d}-aspartate antagonists as well as those of gamma amino butyric acid agonists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

黄金选冶技术发展述评

以国内外黄金选冶成熟技术,工艺的发展为主线,对目前工业生产上具有推广意义的技术、工艺、设备和药剂进行了综述和评价,重点介绍了具有工业发展前景的新技术、新工艺,新设备和新药剂。     

Cyclohexyl nitrite encounter

A brown glass bottle containing yellow liquid was submitted for examination for the presence of common controlled substances. While no controlled substances were detected, the liquid was identified as impure cyclohexyl nitrite, a compound of the same chemical class as amyl and butyl nitrite, which are known for their abuse potential. A bottle labeled cyclohexyl nitrite, but not confirmed by analysis, is the only known previous case submitted to this lab. The case history, examination, and analytical results are presented.     

Cultural orientation and use of cannabis and inhalants among secondary school children in Zimbabwe

A survey among 3061 secondary school children in four provinces in Zimbabwe was conducted in 1994. In the present paper, the relationships between cultural and social factors and use of inhalants and cannabis are explored. Respondents were selected by means of a two-stage sample design, first based on a complete list of schools in the four provinces and subsequently on lists of students at the randomly selected schools. Stratification was based on the identification of four different sociocultural groups. Data collection followed standardised procedures and was conducted by a research team from University of Zimbabwe. Cultural orientation was operationalised by means of a Likert-type 14-item scale on choice of media, language and music. Exploratory principal component analysis revealed a two-factor solution, representing a global or Western cultural orientation and a local or Zimbabwean cultural orientation. Drug use by older siblings and best friends represented social factors. A combined model of cultural and social variables was subject to a multiple logistic regression analysis. Results revealed that the social variables and global cultural orientation were significantly associated with increased use of both drugs, whereas a local cultural orientation was found not to be associated with use of these substances. Findings are discussed in the light of historical and cultural factors.     

Autocatalytic oxidation of hemoglobin by nitrite: a possible mechanism

Oxidation of oxyhemoglobin by nitrite ions to produce methemoglobin is one of the more employed procedures to oxidize the hemoprotein. The process takes place readily after a clear induction time. This behaviour is usually explained in terms of an autocatalytic reaction mechanism. However, the generally accepted mechanism is not autocatalytic and cannot explain the main features of the process. In the present work it is proposed that the characteristics of the process require the occurrence of a fast reaction between oxyhemoglobin and nitrogen dioxide. This process acts as a branching step, leading to the observed autocatalysis.     

Elimination of artifacts in MRCP: technical consideration

Artifacts of MR cholangiopancreatography (MRCP) include fluid-filled gastrointestinal tracts, respiratory motion artifacts, spasm of Oddi's sphincter, vascular compression of bile ducts, overlapping of various anatomical structures and bright signal of surrounding fatty tissue. In this article, various technical considerations to eliminate these artifacts were described for the better imaging analysis of MRCP. The use of high-concentration ferric ammonium citrate (Ferriseltz) is recommended to reduce bright signal of fluid-filled gastrointestinal tracts. In case of long breathhold sequences, O2-inhalation study is useful to eliminate respiratory motion artifacts. Careful attention should be paid to the spasm of Oddi's sphincter and the vascular compression of bile ducts to avoid erroneous interpretation of MRCP findings.     

Brain spatula with transparent tip: technical note

A newly developed brain spatula with transparent tip for brain retraction is introduced. The high-molecular polymer plastic material is used only for the tip of the new spatula whilst rest of the spatula is made up of the ordinary malleable metal. The transparent nature of the spatula tip helps us in observing the retracted brain vessels and cranial nerves in continuity with the main operating area. The extent of distortion as a result of the retraction can be directly observed assisting in prevention of an inadvertent injury. The new brain spatula with transparent tip is helpful for microneurosurgery under high magnification. Various shapes and sizes of the spatula can be used.     

Permanent cardiac pacemakers in children: technical considerations

Placement of permanent cardiac pacemakers in children presents technical problems that are not encountered in the adult. Problems unique to pacemaker implantation in children are related to the patient's size, the relative bulkiness of pulse generators, the lack of subcutaneous tissue, and the child's growth and long life expectancy. Based on our experience with implantation of 27 permanent cardiac pacemakers in 13 children, we have found that the use of small pulse generators, placement of epicardial leads, insertion of properitoneal pulse generators, and use of recharabeable pacemakers are satisfactory methods in children.     

MR cholangiography: technical advances and clinical applications

Magnetic resonance (MR) cholangiography is a fast, accurate, noninvasive alternative to endoscopic retrograde cholangiography (ERC) in the evaluation of biliary tract disease. Technical improvements in imaging sequences (eg, half-Fourier rapid acquisition with relaxation enhancement) and use of phased-array coils allow high-quality imaging comparable to that available with ERC. In choledocholithiasis, common bile duct stones as small as 2 mm can be detected with MR cholangiography and appear as low-signal-intensity foci within the high-signal-intensity bile. MR cholangiography may help establish the diagnosis of malignant obstruction and is useful in the evaluation of patients in whom ERC was unsuccessful or incomplete. The role of MR cholangiography in the evaluation of intrahepatic duct disease continues to evolve. MR cholangiography plays a crucial role in evaluating postsurgical biliary tract alterations and can be used to demonstrate a variety of congenital anomalies of the biliary tract (eg, aberrant ducts, choledochal cysts, pancreas divisum). In addition, intentional or incidental imaging of the gallbladder with MR cholangiography can be used to identify calculi or help determine the presence and extent of neoplastic disease.     

New stent delivery balloon: a technical note

This study reports the first clinical application of a new noncompliant balloon composed of a middle polyurethane layer sandwiched between an inner layer of polyethylene terephtalate and an outer membrane that provides for consistent even expansion. With this balloon design, the very low compliance and high pressure resistance of polyethylene terephthalate are associated with the high elasticity of polyurethane, preventing balloon damage from stent crimping and expansion and allowing a firm embedding of the stent struts. Palmaz-Schatz stent implantation was successful in 33/35 stents (94%), and the two stents that could not be advanced up to the lesion were successfully withdrawn. High pressure expansion of the stent was obtained during deployment with no balloon ruptures at inflation pressures equal or lower than 16 atmospheres (atm). Accurate positioning of the stent was facilitated by the two markers at the balloon ends and by the optimal visualization after contrast injection, even with 6 Fr guiding catheters. This new delivery system maintains the advantages of hand-crimped stents on noncompliant balloons, reducing the risk of stent loss.     

Tension-free hernioplasty: technical remarks and personal experience

The authors report their experience with 463 tension free hernioplasty procedures for inguinal and femoral hernias. The surgical technique included the insertion of both a polypropylene plug and a polypropylene mesh, and was carried out mostly in local anesthesia (84.2%) using bupivacaine 0.25% for ileoinguinal and ileohypogastric blockage and mepivacaine 0.5% for local infiltration. There was no major intraoperative complication; local postoperative complications were rare (10%) and easily managed; postoperative pain was frequently observed (66%), though mild and transient; resumption of working activity occurred within a month in 96.6% of cases; there were only 3 post-operative recurrences (respectively, at 1, 6 and 12 months). The authors conclude that the tension free hernioplasty is a simple, rapid, low-cost and effective technique, easily performed under local anesthesia.     

The custom implant impression coping: technical note

Unsupported soft tissue can collapse around a submerged implant or abutment head during the time interval between removal of the provisional prosthesis and placement of the impression material. A technique is described for accurately recording the implant or abutment position as well as the position of the soft tissue for a single tooth restoration using the provisional prosthesis as a custom implant impression coping.     

A new coated bipolar coagulator: technical note

BACKGROUND: Sometimes charring or popping occurs and the bipolar blades get stuck to the vessel. METHODS: The tips of one of the many commercially available bipolar forceps were coated in a striped manner with Teflon--50 micro in thickness. RESULTS: The new bipolar coagulator coated with Teflon reduced the incidence of tissue sticking. CONCLUSIONS: Experience with this instrument was still quite limited, but preliminary results were promising.     

Comparative epidemiology of dependence on tobacco, alcohol, controlled substances, and inhalants: Basic findings from the National Comorbidity Survey.

Studying prevalence of Diagnostic and Statistical Manual of Mental Disorders-III-Revised (DSM-III-R) drug dependence among Americans 15–54 yrs old, the authors found about 1 in 4 (24%) had a history of tobacco dependence; about 1 in 7 (14%) had a history of alcohol dependence, and about 1 in 13 (7.5%) had a history of dependence on an inhalant or controlled drug. About one third of tobacco smokers had developed tobacco dependence and about 15% of drinkers had become alcohol dependent. Among users of the other drugs, about 15% had become dependent. Many more Americans age 15–54 have been affected by dependence on psychoactive substances than by other psychiatric disturbances now accorded a higher priority in mental health service delivery systems, prevention, and sponsored research programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Accidental acute fatal sodium nitrite poisoning

OBJECTIVES: To report two patients who developed reactive arthritis in association with Staphylococcus aureus infection. METHODS: A review of the case notes of two patients. RESULTS: Two adult female patients have developed sterile arthritis in association with Staph aureus infection. The first patient has had two episodes of arthritis; the first followed olecranon bursitis, the second followed infection of a central venous catheter used for dialysis. The second patient developed sterile arthritis while being treated for pyomyositis. Both patients had a self limited arthritis and were HLA-B27 negative. CONCLUSION: Reactive arthritis may rarely follow Staph aureus infection. HLA-B27 negativity may be associated with a self limited arthritis in these cases.