Protease inhibitors: a therapeutic breakthrough for the treatment of patients with human immunodeficiency virus

As one of the largest growing classes of antiretroviral drugs, protease inhibitors are promising agents for the management of patients infected with the human immunodeficiency virus (HIV). We reviewed the literature and compared efficacy, dosing, side effects, and drug-interaction profiles of the protease inhibitors saquinavir, ritonavir, indinavir, and nelfinavir. We addressed the use of these antiprotease agents as monotherapy versus use in combination therapy with other antiretroviral medications, and the potential for HIV to develop resistance to this drug class. We also discussed therapy with dual protease inhibitors and the use of protease inhibitors in pregnant or lactating women and in pediatric patients. Finally, we examined case reports of the addition of protease inhibitors to an antiretroviral regimen that ultimately decreases or reverses opportunistic infections.

Copper radionuclides and radiopharmaceuticals in nuclear medicine

The chemistry, radiochemistry, radiobiology, and radiopharmacology of radiopharmaceuticals containing copper radionuclides are reviewed. Copper radionuclides offer application in positron emission tomography, targeted radiotherapy, and single photon imaging. The chemistry of copper is relatively simple and well-suited to radiopharmaceutical application. Current radiopharmaceuticals include biomolecules labelled via bifunctional chelators primarily based on cyclic polyaminocarboxylates and polyamines, and pyruvaldehyde-bis(N4-methylthiosemicarbazone) (PTSM) and its analogues. The chemistry of copper, of which only a fraction has yet been exploited, is likely to be applied more fully in the future.

The use of a bilobed flap in the correction of radial club hand

A new incision is described for the correction of radial club hand. By the use of a bilobed flap, redundant skin is transferred from the ulnar side of the wrist to the radial side, where there is tension as the wrist becomes straight. The flap has been shown to be safe and effective in six consecutive cases, and access to the wrist and surrounding soft tissue structures is excellent.

New techniques and instruments for lens implantation

Although most of the new techniques and new instrumentation for intraocular lens implantation are related to foldable intraocular lenses or sutured posterior chamber lenses, there are some intriguing new concepts in intraocular lens techniques unrelated to these two areas.

Tumoral calcinosis associated with congenital malformations of the hand

Two cases of tumoral calcinosis are reported in children with congenital hand malformations. After excision of large calcific masses, reconstruction was performed using a free phalangeal graft in one case and a free toe transfer in the other.

Direct DNA probe assay for Neisseria gonorrhoeae in pharyngeal and rectal specimens

The direct detection of gonococcal DNA in rectal and pharyngeal specimens was evaluated by using a DNA probe-based assay (Gen-Probe, Inc., San Diego, Calif.). Rectal (234) and pharyngeal (608) swab specimens were obtained from 249 men and 372 women attending sexually transmitted disease clinics in Las Vegas and Reno, Nevada. The prevalence of gonococcal infection by culture at the pharyngeal and rectal sites was 2.9% (16 of 548 specimens) in women and 2.7% (8 of 294 specimens) in men. No false-positive reactions were observed among the 234 rectal specimens tested. Two probe-positive, culture-negative specimens were detected among the 361 pharyngeal specimens obtained from women. Both of these samples were confirmed as Neisseria gonorrhoeae by a probe competition assay. The overall correlation of the DNA probe test with pharyngeal and rectal cultures was 99.4% (837 of 842 cultures), with a sensitivity of 87.5% (21 of 24 cultures) and specificity of 99.7% (816 of 818 cultures). The positive and negative predictive values of the DNA assay were 91.3 and 99.8%, respectively. The direct DNA probe assay provides an alternative to culture screening for rectal and/or pharyngeal gonococcal infections.

Sulcus fixation without flaps

BACKGROUND

Numerous techniques for sulcus fixation of posterior chamber implants in the absence of capsular support have been reported. All rely on partial thickness scleral flaps or the conjunctiva to prevent the requisite polypropylene knot from eroding. The author compares their success with that of a new surgical procedure. This new technique buries the knot within the eye.

METHODS

One hundred scleral-sutured, sulcus-fixated cases were studied retrospectively. Each case was performed by the author or by a resident under this direction. Suture erosion was defined as the absence of scleral or conjunctival cover on part of the polypropylene suture.

RESULTS

On 60 patients, partial thickness scleral flaps were used to protect the knot from exposure. Twelve (20%) of these patients had some degree of externalization of the suture. Of the 40 patients in whom knots were buried and no scleral flap was used, no (0%) erosion was observed.

CONCLUSION

Sulcus fixation of posterior chamber knots has been criticized for increasing the risk of endophthalmitis. The track formed by an exposed suture allows an infectious agent to pass from the external eye to the supported intraocular lens (IOL). Scleral flaps add a degree of safety, but the knot can erode after several months. The author advocates burying the knot within the eye to avoid erosion and therefore endophthalmitis.

Drafting a parenteral nutrition order form utilizing a physician assessment process

The utilization of a physician critique process in the design of a parenteral nutrition order form, encouraging a standard order option, is assessed. In the critique process, physicians from surgery, medicine, and medical intensive care teams were tasked to use the draft order form and guideline sheet to prescribe a parenteral nutrition order for a hypothetical patient. Prescriber recommendations and problems with the nutrition order form and guideline sheet directed editorial improvements. The physician assessment process is an effective means to measure utility of a draft parenteral order form and prescribing guideline sheet. By utilizing physician expertise, deficiencies inherent in such an order form may be corrected prior to implementation.

Assessing physician variability in parenteral nutrition orders given a set of patient parameters as a means of determining educational needs

Diversity of physician training and experience results in variability of physicians' assessments of total parenteral nutrition needs for patients. The Surgery, Medicine, and Medicine Intensive Care team members at the Walter Reed Army Medical Center, Washington, DC, were asked individually to prescribe a parenteral nutrition order for a hypothetical patient with a given set of characteristics and laboratory parameters. The parenteral nutrition order form used provided the options of individualized or standardized total nutrient admixture/peripheral parenteral nutrition formulas. The variability of these orders was assessed and used as a basis for medical team education and individual prescriber counselling.

Evaluation of the PACE 2 Neisseria gonorrhoeae assay by three public health laboratories

The Gen-Probe PACE 2 DNA probe assay for Neisseria gonorrhoeae was compared with conventional culture techniques in three Florida public health laboratories with 436 patients (271 females and 165 males). The prevalence rates based on culture were 19.9, 55.8, and 33.5% for females, for males, and overall, respectively. Twenty-seven probe-positive specimens gave negative culture results. Twenty of these specimens were resolved as true positives after retesting with a probe competition assay. The resolved sensitivity, specificity, positive predictive value, and negative predictive value were 99.4, 99.6, 99.4, and 99.6%, respectively.

Corneal argyrosis associated with silver soldering

We report a patient who developed corneal argyrosis secondary to occupational silver soldering. Clinically, the cornea was notable for a green-brown discoloration localized to Descemet's membrane by slit-lamp biomicroscopy. Silver particles were identified within the anterior three eighths of Descemet's membrane by light and electron microscopy and energy-dispersive x-ray microanalysis. To our knowledge, the association between corneal argyrosis and silver soldering has not been previously reported.

Urinary leukocyte esterase test: a screening method for the detection of asymptomatic chlamydial and gonococcal infections in men

The ability of a urinary dipstick leukocyte esterase test (LET) to predict culture-verified asymptomatic urethral infections of Chlamydia trachomatis and Neisseria gonorrhoeae was determined in 1095 men (aged 18-39) who presented to an urban hospital for acute general medical care. Prevalence of chlamydial and gonococcal infections were 4% and 2.5% respectively; LET sensitivity was 41% and specificity was 91%. In the youngest one-third, the prevalence of infection and LET sensitivity and specificity increased to 9%, 58%, and 93%, respectively. Higher inclusion count in chlamydia culture was also significantly correlated with younger age. This is the first study to assess LET performance as a screening test for asymptomatic disease in adult men and suggests that LET has promising accuracy in young men but is less likely to be a useful screening test in men greater than 25 years old.

Ab externo sulcus fixation

A new suturing method for sulcus fixation of posterior chamber lenses is described. This technique involves using a 28-gauge hollow-bore needle on an insulin syringe and a straight suture needle carrying 10-0 polypropylene. Both of these needles penetrate the eye wall in ab externo fashion, with measurements guiding their insertion. This technique promotes reproducible suture placement and reliable sulcus fixation of the implant.

Functional use of the Nucleus 22-channel cochlear implant in the elderly

A questionnaire was sent to 101 Nucleus 22-channel cochlear implant recipients aged 65 years and older to investigate the perceived impact of cochlear implantation on their quality of life. The questionnaire was designed to gain insight into the patient's daily use of the Nucleus implant. Sixty-seven questionnaires were returned over a 3-month period. The results of the survey showed that elderly cochlear implant patients obtained similar benefits to younger adult patients who were implanted with the same device. We believe that the results of this study will aid other centers when counseling elderly patients on the expected daily functional benefits of this device.

DNA probe confirmatory test for Neisseria gonorrhoeae

A DNA probe test for the culture confirmation of Neisseria gonorrhoeae in clinical isolates was evaluated with 156 isolates of N. gonorrhoeae and 120 isolates of nongonococcal Neisseria species, organisms representative of other genera within the family Neisseriaceae, and organisms isolated on media selective for N. gonorrhoeae. The 30-min test used a chemiluminescent DNA probe that was homologous to rRNA sequences of N. gonorrhoeae. We report here a specificity and a sensitivity of 100% with the 276 clinical isolates tested, including 43 gonococcal strains that had been misidentified by other methods.

Vertical Distribution of Water in the Atmosphere of Venus: A Simple Thermochemical Explanation

Several lines of evidence concerning the vertical abundance profile of water in the atmosphere of Venus lead to strikingly unusual distributions (the water vapor abundance decreases sharply in the immediately vicinity of the surface) or to serious conflicts in the profiles (different infrared bands suggest water abundances that are discrepant by a factor of 2.5 to 10). These data sets can be reconciled if (i) water molecules associate with carbon dioxide and sulfur trioxide to make gaseous carbonic acid and sulfuric acid in the lower atmosphere, and (ii) the discrepant 0.94-micrometer water measurements are due to gaseous sulfuric acid, requiring it to be a somewhat stronger absorber than water vapor inthis wavelength region. A mean total water abundance of 50 +/- 20 parts per million and a near-surface free water vapor abundance of 10 +/- 4 parts per million are derived.

Histologically documented transformation of benign oral melanosis into malignant melanoma: a case report

A case of histologically documented transformation of benign intraoral melanosis into malignant melanoma is presented. Because benign oral melanotic lesions can transform into malignant melanoma, all intraoral melanotic lesions should be completely excised with histologically proven free margins.

Biological effects of magnetic fields: chronic exposure of the nematode Panagrellus redivivus

The Panagrellus redivivus bioassay, an established monitor of adverse toxic effects of different environments, has been used to study the biological effects of exposure to static and time-varying uniform and gradient magnetic fields, and to time-varying magnetic field gradients superimposed on a static uniform magnetic field of 2.35 Tesla. Temporally stationary magnetic fields have no effect on the fitness of the test animals. Time-varying magnetic fields cause some inhibition of growth and maturation in the test populations. The combination of pulsed magnetic field gradients in a static uniform magnetic field also has a small detrimental effect on the fitness of the test animals.

Gonococcal urethritis diagnosed from enzyme immunoassay of urine sediment

First-catch urine specimens were obtained before clinical examination from 101 sexually active men who attended a sexually transmitted diseases clinic with a complaint of urethral discharge. Urethral swab specimens were used for preparation of smears and were then cultured on Martin-Lewis medium. Enzyme immunoassay (EIA) tests were performed on (1) uncentrifuged urine, (2) urine sediment, and (3) urine sediment diluted 1:6 with detergent buffer. Urethral cultures from 65 (64%) of the 101 men were positive for N. gonorrhoeae. EIA performed on urine sediment diluted 1:6 yielded the highest sensitivity: 98.5% (64/65). Sensitivity of EIA for uncentrifuged urine was only 66% (43/65). Specificity of all samples tested exceeded 97.2%. Overall agreement between results of EIA on diluted urine sediment and culture was 98% (99/101). Discordant culture and EIA results were unrelated to urine volume, time since prior urination, quantity of gonococcal growth on Martin-Lewis medium, duration of urine storage (less than 72 hours) before testing, or immunotype. EIA tests using urine sediment are highly sensitive and specific, and they offer an alternative means of diagnosing gonorrhea in men who refuse urethral manipulation. They also provide a means of screening men at high risk for gonorrhea who have submitted a urine specimen for other reasons.