Tattoo associated retinochoroiditis. / Retinocoroiditis asociada a tatuaje.

CLINICAL CASE: A young woman was referred to our offices with impairment of visual acuity after she received a third tattoo on her arm. Systemic medical and laboratory work-up were performed in order to exclude an infectious agent or inflammatory disease. A yellowish juxtafoveal lesion in left eye along with a plaque-like outer retinal disruption and focal pigmentary defects was assessed using multi-modal diagnostic imaging. DISCUSSION: Ophthalmologists treating uveitis should consider this uncommon association and question patients regarding tattoos and tattoo inflammation given the rise of subjects undergoing artistic tattooing.

Drug-induced liver injury. In vitro demonstration of hypersensitivity to both phenytoin and phenobarbital.

Fever, lymphadenopathy, exfoliative dermatitis, and evidence of drug-induced liver injury developed in a 16-year-old girl three weeks after beginning therapy with phenytoin and phenobarbital. This clinical syndrome can be caused by either of these structurally related drugs but has been more frequently attributed to phenytoin. In vitro studies disclosed marked reactivity of this patient's lymphocytes to concentrations of both drugs, which encompassed their measured serum levels. The demonstration of dual reactivity raises concerns about continuing administration of phenobarbital during an apparent phenytoin-induced reaction. Whether this potential risk is greater than the risk of stopping all anticonvulsant medications in a patient with a seizure disorder is not known and remains to be established.

A simple technique for the rapid enrichment of class and subclass hybridoma switch variants. A 1000-fold enrichment in half the time, for half the cost.

Switching parental hybrids in vitro to downstream switch variant clones producing more desirable monoclonal antibodies (MoAbs) requires either labor intensive and time consuming subcloning techniques, or fluorescence activated sorting of the desired clones. We tested the hypothesis that enrichment of downstream switch variant clones might be achieved by selective lysis of upstream hybridoma cells followed by expansion of the enriched downstream clone. Using a parental hybridoma with surface and secretory IgM, we attempted to enrich downstream switch variant clones producing class (IgG) and subclass (IgG1 or IgG2a) MoAbs. Enrichment of downstream IgG, IgG1 and IgG2a MoAb-producing switch variants was achieved by single or repeated antibody-dependent, complement-mediated lysis of the upstream IgM-bearing parental hybridoma cells followed by limited subcloning. Two exposures of parental hybridoma cells to lysis followed by plating at 100 cells/well enriched the frequency of switch variants up to 1235-fold, enabling the development of IgG1 or IgG2a-producing subclones exhibiting high yield antibody production. Using this protocol, production time and costs were reduced by > 50% when compared to the standard technique. This novel technique for the rapid isolation and expansion of switch variant clones should be ideal for most laboratories, particularly those without access to cell sorting capabilities.

Immunologically diagnosed malignancy in Sjögren's pseudolymphoma.

Studies of lymphocyte markers in a patient with Sjögren's syndrome who exhibited histologically benign lymphoproliferation in the lung revealed a malignant cell clone. T and B cells were quantitated according to their ability to form spontaneous rosettes with sheep erythrocytes and to fluoresce with fluorescein-conjugated antiserums, respectively. Circulating lymphocytes were 66 percent T cells (N = 58 +/- 2 per cent) and 14 percent B cells (N = 22+/- 1 percent), the latter exhibiting normal polyclonal distribution of membrane immunoglobulins. However, lymphocyte suspensions obtained from fresh lymph node and from biopsy specimens from a lymphoid lung nodule revealed 95 percent and 88 percent B cells, with 1 percent and 2 percent T cells, respectively. Moreover, when cryostat-frozen sections from both tissues were reacted with each of the heavy and light chain-specific antiserums, most cells demonstrated the presence of intracytoplasmic mu kappa immunoglobulin exclusively. Twenty-two months later, a clinically and histologically classic lymphoma developed. Repeat marker studies performed on cells freshly isolated and on frozen sections from the histologically malignant lymph node revealed persistence of the monoclonal marker on most cells.

CD20 and CD5 expression in B-chronic lymphocytic leukemia.

In order to quantitate a previously noted decrease in CD20 fluorescence intensity (FI) on B-CLL lymphocytes, binding capacities [BC x 10(3) +/- 1SD = number of antibodies bound per cell] were calculated. The mean (N = 5) BC x 10(3) +/- 1SD of CD20 reagents for normal B-PBL and B-CLL lymphocytes confirmed this observation. B-PBL and B-CLL were 56 +/- 11 and 61 +/- 14, and 19 +/- 15 and 18 +/- 16, respectively, for Leu 16 and B1. Although adequate compensation standards for the determination of CD5 and CD20 coexpression are not available, qualitatively, the density of CD5 on both normal B-PBL and B-CLL is less compared to the expression of CD5 by normal T cells. CD5 expression on B-CLL seems to be linked to the lower levels of CD20, whereas CD5 expression may appear to be absent on CLL lymphocytes expressing normal levels of CD20. Levels of CD20 in B-CLL suggest involvement of one or two genes (alleles) whose decreased expression may be linked to CD5 expression.

Reducing postischemic paraplegia using conjugated superoxide dismutase.

Paraplegia after thoracic aortic aneurysm repair has an incidence of 2.2% to 24%. Oxygen-derived free radicals after reperfusion of an ischemic spinal cord may be partly responsible for neuronal destruction. We studied the effects of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD), a free radical scavenger, as a way of increasing spinal cord tolerance to ischemia. Thirty rabbits underwent 40 minutes of aortic occlusion (a known model of paraplegia). Ten of these animals received 25,000 U/kg of PEG-SOD 24 hours before aortic occlusion and two additional doses of 10,000 U/kg, one before and one subsequent to spinal ischemia. Ten animals received superoxide dismutase in the same dosages as those receiving PEG-SOD. Ten control animals received placebo. All animals were studied for 96 hours, at which time a final neurological examination was performed and the results were recorded. Of the 10 animals treated with PEG-SOD, 2 were completely paralyzed whereas 8 had less (7) or no (1) neurological impairment. Eight of the 10 control animals and 9 of the 10 animals receiving superoxide dismutase were completely paralyzed. None of the control animals or animals receiving superoxide dismutase had a normal neurological examination (p less than or equal to 0.05). Treatment with PEG-SOD before and during occlusion increased the rabbit spinal cord tolerance to a 40-minute ischemic insult. Scavenging free radicals may lessen experimental spinal cord injury.

Denervation of transplanted porcine lung causes airway obstruction.

Lung transplantation can be complicated by a form of small airway obstruction known as bronchiolitis obliterans. We tested the hypothesis that lung denervation causes small airway obstruction in young pigs (10 +/- 1 weeks). Control pigs had an innervated native lobe, and study pigs had either a denervated native lobe or a denervated transplant lobe. Transplanted pigs received standard immunosuppression. At 10 weeks we measured isolated left lobe pulmonary mechanics. Dynamic resistance in both study groups was significantly higher than in the lobectomy group, whereas dynamic compliance in both study groups was significantly lower than in the lobectomy group. No significant difference in resistance or compliance was noted between the transplant and reimplant groups. Histologic changes consistent with rejection were noted in the transplant lobes. We conclude that the small airway obstruction noted in this model is due to operative denervation rather than to immunosuppression or rejection.

Monoclonal antibody production to human and bovine 2':3'-cyclic nucleotide 3'-phosphodiesterase (CNPase): high-specificity recognition in whole brain acetone powders and conservation of sequence between CNP1 and CNP2.

Monoclonal antibodies against human and bovine 2':3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) were generated by fusing FOX-NY myeloma cells with spleen cells from RBF/Dn mice previously immunized with the purified brain antigens. The enzyme isolated from bovine brain was quite basic, with an isoelectric point of 9.71 and both the bovine and human enzymes consisted of a closely spaced doublet at approximately 44 and 46 kDa on SDS-PAGE. Six monoclonals were were identified as strongly recognizing the enzyme on both ELISA plates and on immunoblots of whole brain protein. Four monoclonals very weakly cross-reacted with guinea pig myelin basic protein. In contrast with two previous reports, some of our monoclonal antibodies did immunostain 2 or 3 protein bands in peripheral nerve, two bands closely corresponding to those immunostained in central nervous system (CNS) myelin, the Wolfgram protein fraction and in acetone powders of whole brain. Each of the 6 monoclonals reacting strongly on immunoblots recognized the enzyme in from 2 to 5 of the species examined (human, bovine, rat, mouse and rabbit). In addition, all 6 monoclonals that immunostained the enzyme in whole brain, myelin and Wolfgram protein immunoblots recognized both CNP1 (44 kDa) and CNP2 (46 kDa). The two closely spaced protein bands observed on SDS-PAGE and previously stained on immunoblots of CNS CNPase using polyvalent rabbit anti-bovine CNPase antisera, and now different monoclonal antibodies, appear to be immunologically related and to contain highly conserved sequences.

The chronic lymphocytic leukemia antigen (cCLLa) as immunotherapy target: pharmacokinetics and biodistribution of two divalent, ricin-based immunotoxins in xenografted athymic mice.

The chronic lymphocytic leukemia (CLL) antigen (cCLLa) is potentially suitable for targeted immunotherapy given its restriction to clonal CLL cells and lack of expression by normal lymphocytes. In order to assess the pharmacokinetics and biodistribution of two potent anti-cCLLa immunotoxins (ITs) were examined in the mouse model. The IgG fraction of anti-cCLLa monoclonal antibody CLL2m was conjugated with 125I-labeled intact (RTA) or deglycosylated (dgA) ricin chain A, injected intravenously into athymic mice engrafted with cCLLa-expressing human tumors, and monitored over 120 hours. Blood concentrations of CLL2m/125I-RTA and CLL2m/125I-dgA were best fit to biexponential equations but the latter exhibited a lower alphaT1/2 and betaT1/2 (4.1 and 102 min vs 5.9 and 126 min), a smaller volume of distribution (5.1 g vs 9.7 g), and a lower blood clearance (2.2 g/hr vs 4.6 g/hr). Both ITs exhibited preferential tumor uptake that followed distinct kinetics: rising tumor uptake for 2 hrs post-injection (while tissue uptake decreased), reaching tumor/non-tumoral tissue uptake ratios up to 16.9; and slower dissociation rates of tumor- vs tissue-bound ITs (>45% vs <20% remaining tissue-bound 6 hrs post-injection, respectively). Non-specific liver uptake was not prominent for either IT. In vivo IT deconjugation reached 50% approximately 12 hours pos-injection. The pharmacokinetics and biodistribution data in the mouse model suggest that ricin-based anti-cCLLa ITs are suitable for use in human trials.

The chronic lymphocytic leukemia antigen (cCLLa) as immunotherapy target: assessment of LD50 and MTD of four ricin-based anti-cCLLa immunotoxins (ITs) in Balb/c mice.

The chronic lymphocytic leukemia (CLL) antigen (cCLLa) is a promising immunotherapy target given its disease-restricted expression, its highest prevalence among CLL surface antigens, and its lack of expression by normal T- and B-lymphocytes. The objectives of this study were to assess the 50% lethal dose (LD50) and the maximum tolerated dose (MTD) in Balb/c mice of four anti-cCLLa immunotoxins (ITs) derived from the intact monoclonal antibody (MoAb) or its Fab fraction, each conjugated to either ricin chain-A (RTA) or its deglycosylated derivative (dgA). The IgG fraction of anti-cCLLa monoclonal antibody CLL2m and its Fab fraction were conjugated to RTA or dgA to generate four ITs: IgG/RTA, IgG/dgA, Fab/RTA and Fab/dgA. Progressive concentrations of each IT (ranging between 2.60 mg/kg and 100.00 mg/kg) were injected intravenously into groups of 5 mice each. After injection, mice were monitored daily for 10 days for survival. Observed mortality data in each group were matched to those in Weil's tables for estimating LD50 (mg/kg) from the moving average interpolation method. Estimated LD50 (in mg/kg) were: IgG/RTA, 13.33; Fab/RTA, 25.53; IgG/dgA, 55.33; Fab/dgA, 55.33. Their respective MTD (mg/kg), defined as the highest dose level survived by all mice, were 8.78, 13.17, 29.63 and 29.63. Depending on the animal-to-human extrapolation method used, the calculated LD50 and MTD in humans ranged from 1.2 mg/kg and 0.8 mg/kg (IgG/RTA), to 55.6 mg/kg and 36.9 mg/kg (IgG/dgA and Fab/dgA), respectively. The following conclusions are drawn. 1. Antibody valence exerted little influence on either the LD50 or the MTD; 2. The LD50 to MTD ratios were approximately 2:1; 3. dgA-derived ITs were approximately one half as toxic as their RTA-derived counterparts; and 4. Extrapolation of LD50 and MTD mouse data to humans resulted in dose levels comparable to or exceeding those reported in most IT human trials. These data suggest the suitability of anti-cCLLa ITs for clinical immunotherapy trials.

Treatment principles for proximal and middle phalangeal fractures.

After a proximal phalangeal fracture, optimal results are obtained by methods that permit active interphalangeal joint motion and tendon gliding during fracture healing. Typical apex palmar angulation of proximal phalangeal fractures demonstrates dorsal skeletal shortening and secondary incompetence of the extensor mechanism with PIP joint extensor lag. Apex palmar deformities of the middle phalangeal fractures demonstrate similar problems with skeletal shortening resulting in loss of distal joint extension. Proximal and middle phalangeal shaft fracture deformities rotate about their flexor tendons and their fibro-osseous tunnels. Functional restoration requires accurate skeletal realignment that restores normal skeletal length necessary for extensor tendon competence. A splint that holds the wrist in slight extension and all four finger MP joints in full flexion combined with active interphalangeal joint exercises form the essential elements of postoperative care.

External fixation. Technical advances based upon multiplanar ligamentotaxis.

The principle of ligamentotaxis obtained by longitudinal traction is useful in restoring skeletal length to distal radial fractures. Using external skeletal fixation to translate the hand in radial-ulnar and dorsal-palmar directions, ligamentotaxis in two additional planes aligns and tilts the distal radial fragment and its articular surface. Following restoration of palmar tilt by palmar translation, wrist position can be adjusted into neutral or extension to help avoid finger stiffness and carpal tunnel syndrome without compromising fracture reduction.

The anatomy of the flexor digitorum superficialis relevant to tendon transfers.

The flexor digitorum superficialis is a diagastric muscle with a proximal muscle belly from which the tendons to the index, ring and little fingers arise. These tendons are not independent and are not good motors for non-synergistic transfers, such as for finger extension. The muscle and tendon to the middle finger arise separately and are therefore more suitable for non-synergistic transfers.

Distal radius fractures. Multiplanar ligamentotaxis.

Ligamentotaxis is the principle of molding fracture fragments into alignment as a result of tension applied across a fracture by the surrounding intact soft tissues. Uniplanar ligamentotaxis obtained by longitudinal traction does not always restore palmar tilt to the distal radius. Multiplanar ligamentotaxis extends the principle of uniplanar ligamentotaxis to include translation of the hand in the dorsal-palmar and the radial-ulnar planes to effect appositional and tilting alignment of the distal fragment(s) of a fractured radius. Use of an external fixator that allows adjustments in multiple planes helps restore anatomic alignment and maintain fracture reduction during healing.

Endoscopic carpal tunnel release using the single proximal incision technique.

The goal of the single incision endoscopic technique is to avoid an incision on the palmar surface of the hand. As compared with open release and the two-portal endoscopic technique for release of the carpal tunnel, this single incision technique permits the patient to return earlier to work and activities of daily living as a result of less tenderness and earlier return of strength. Safe performance of the technique requires that the surgeon have both a thorough knowledge of the anatomy of the hand and a commitment to master the technical details of the surgical approach. Because the technique is of value strictly to view and divide the TCL, patient selection requires careful preoperative evaluation to exclude those carpal tunnels with pathology that requires direct inspection or surgical treatment. In a prospective study with the redesigned point of entry blade assembly that allows a view of the blade's entry into the ligament, no device-related complications occurred. In considering a surgical approach for endoscopic carpal tunnel release, the authors feel that it is important to recognize the value of an "open" proximal surgical incision designed to directly view the plane between the finger flexor synovium and the deep surface of the TCL. Stab wound "portals" that are widely used in arthroscopic surgery are inadequate for endoscopic carpal tunnel releases. The device and the procedure are designed to obtain an unobstructed view of the underside of the TCL and divide it completely. Additional long-term prospective studies are needed to define the comparative recurrence rates of open versus single incision endoscopic carpal tunnel release surgeries.

Treatment of comminuted distal radius fractures: an approach based on pathomechanics.

Following dorsally displaced fractures of the distal radius, the classic position of immobilization is with the wrist flexed and in ulnar deviation. This is not the position of function and entails morbidity in the form of finger stiffness, which may require prolonged rehabilitation. We treated 20 consecutive, comminuted, intraarticular distal radial fractures using a new external fixation system with the wrist in a neutral to extended position, thereby promoting metacarpophalangeal joint flexion by relatively relaxing the finger extensor tendons. Supplemental pin fixation was used in eight cases. Most patients were performing active digital motion on the day of surgery and 95% maintained functional finger motion during treatment. All fractures healed uneventfully. Palmar tilt was restored in 55% of patients in spite of a wrist neutral or extended position. This method of fixing distal radial fractures allows restoration of anatomy while avoiding hand stiffness.