Motor weakness and ataxia of lower limbs and abnormalities of somatosensory evoked potentials occur in many patients with the acquired immunodeficiency syndrome (AIDS). We studied 15 human immunodeficiency virus-seropositive subjects without AIDS and found no clinical neurological abnormalities. The mean latency of the brainstem auditory evoked potential (peak V) was increased, suggesting a central defect. Despite normal peripheral nerve conduction along the tibial nerve, the mean latency of the spinal cord potential of the twelfth thoracic vertebra was increased compared with normal, possibly indicating an incipient conduction defect at or near the spinal root ganglion or lumbar spinal cord.

Acquired Immunodeficiency Syndrome↗

PubMed1988

Segregation analysis of leprosy in families of northern Thailand.

Sixty-three families with multiple instances of leprosy were identified through a major leprosy treatment center in northern Thailand. Complex segregation analyses for single major genes or polygenic inheritance were performed using the maximum-likelihood routine POINTER to determine the most likely etiologic model of genetic susceptibility. Liability differences between men and women were considered in these models. When individuals were considered to be affected because they had any form of leprosy, a generalized major gene model with nearly dominant parameters on the liability scale, but additive penetrances, was found to be the most likely. When only those individuals who had tuberculoid forms of leprosy were considered to be affected, a recessive model was found to be the most likely; however, the discrimination between various models was poor. Further analyses are necessary to delineate genetic mechanisms to explain these apparently divergent results. In particular, methods of testing two locus models should be considered.

Adult↗

PubMed1988

532-nanometer green laser beam treatment of superficial varicosities of the lower extremities.

Green laser light at 532 nm was utilized in an attempt to thrombose and blanch superficial varicosities of the lower extremity in 14 patients. Selective vascular damage with sparing of overlying skin was the theoretical rationale for use of green light. Seven of the 14 patients achieved satisfactory results (total or near-total obliteration of vessels without scarring) after a 6-month period of observation.

Adult↗

PubMed1988

SPECT using Bremsstrahlung to quantify 90Y uptake in Baker's cysts: its application in radiation synovectomy of the knee.

The use of SPECT with Bremsstrahlung radiation has been investigated in studies on patients undergoing 90Y therapy for persistent synovitis of the knee. In particular, its value in the estimation of 90Y uptake into Baker's cysts was assessed and, to this end, realistic 'knee phantoms' were employed in order to calibrate for cysts of different size. Problems associated with the measurement of the extensive Bremsstrahlung spectrum and the estimation of cyst volume have been discussed. It is shown that, although the apparent volume of a cyst is markedly dependent on the chosen count rate threshold, volumes greater than about 30 ml can be estimated with reasonable accuracy using a threshold of 50%. The uptake of 90Y in cysts, measured on 3 occasions within the first 2 days in 10 patients, showed wide variation (0%-40%) between patients and was poorly related to the size of cysts on arthrograms and to the clinical response to therapy. In these studies, the ability to analyse SPECT slices provided a distinct advantage over planar imaging for discriminating between 90Y uptake in cysts and adjacent sites. Retention of 90Y in the total knee was also widely variable, with losses of 2%-38% observed 2 days after injection which, in general, were not fully accounted for by uptake in liver or lymph nodes. The changing distribution of 90Y colloid in the knee during the first two days, as observed in some patients, might explain part of the discrepancy.

Aged↗

PubMed1988

Immunocytochemistry of ovine sporozoan encephalitis and encephalomyelitis.

An indirect immunoperoxidase procedure was developed to detect Sarcocystis spp meronts in paraffin wax sections of infected ovine tissues. Ten rabbits seronegative to Sarcocystis spp and Toxoplasma gondii were injected intradermally or subcutaneously over 2 months with varying quantities (150 to 750 micrograms) of purified soluble cystozoite antigen derived from ovine heart microcysts. Serum from each rabbit was tested against paraffin wax preparations of S. ovicanis cysts, second generation S. ovicanis meronts and T. gondii cysts. Sera from three rabbits reacted with S. ovicanis meronts without any cross reaction to T. gondii antigens. Toxoplasma gondii and Sarcocystis spp-specific sera were used to identify the sporozoa in six cases of naturally-occurring ovine encephalitis or encephalomyelitis. Sarcocystosis was diagnosed in four lambs and toxoplasmosis in one lamb. The generic identity of the sporozoan in the sixth case was not established as meronts reacted with both Sarcocystis spp- and T. gondii-specific sera. The study demonstrates the value of the immunohistological technique of visualizing sparsely distributed meronts in naturally-infected tissues and shows that sporozoa of the genus Sarcocystis and T. gondii, and possibly also sporozoa the identity of which is as yet unclear, are associated with encephalitis of sheep in Britain.

Animals↗

PubMed1988

A fundamental division in the Alu family of repeated sequences.

The Alu family of repeated sequences from the human genome contains two distinct subfamilies. This division is based on different base preferences in a number of diagnostic sequence positions. One subfamily of the sequences, referred to as the Alu-J subfamily, is very similar to 7SL DNA in these positions. The other subfamily, Alu-S, can be divided further into well-defined branches of sequences. These findings revise the previous picture of the Alu family and expose their complex evolutionary dynamics. They reveal sequence variations of potential importance for the proliferation of Alu repeats and relate them to their structural features. In addition, they open the possibility of using different types of Alu sequences as natural markers for studying genetic rearrangements in the genome.

Base Sequence↗

PubMed1988

A simplified recycling model for the dosimetry of radioiodide.

Following the administration of radioiodide, a process of recycling takes place in which part of the radioiodide taken up and organified by the thyroid is subsequently released to re-enter the cycle. The convolution method has been applied to a simplified three-compartment model to predict individual cycles and overall cycling effects in the compartments and to illustrate the influence of various parameters on the effects of recycling. For example, a turnover half-time of 80 d in the thyroid is increased, as a result of recycling, to about 110 d if the thyroid uptake fraction is 0.3, and to about 153 d if the uptake increases to 0.55. An equation is derived for calculating a recycling factor based on values of the model parameters. This factor, which is common to the three compartments of the model, permits calculation of cumulated activities in the compartments allowing for the effects of recycled radioiodide. It is shown how differences in values of thyroid uptake fraction and discharge rate and of the physical half-lives of iodine radioisotopes affect the value of the recycling factor. Dose calculations for 125I, administered as radioiodide, are used to illustrate the above techniques and to examine the effects of recycling on dosimetry. Although recycling can lead to large increases in the doses to some body organs, the thyroid dose greatly exceeds the dose to any other organ and alone accounts for nearly all the effective dose equivalent.

Humans↗

PubMed1988

Tumor lysis syndrome after steroid therapy for anaphylaxis.

A 36-year-old man with mediastinal lymphoblastic lymphoma achieved complete remission with chemotherapy. After 18 months he relapsed in a leukemic phase with hematuria due to thrombocytopenia. While receiving 10 units of random donor platelets, he had anaphylaxis, for which he received epinephrine, diphenhydramine, and intravenous methylprednisolone (125 mg), causing rapid tumor lysis with hyperuricemia, hyperphosphatemia, hypocalcemia, and a rise in creatinine. Treatment with allopurinol and high-volume alkaline diuresis led to recovery of normal renal function within 72 hours. Since steroids are cytotoxic to many leukemias and lymphomas, physicians prescribing transfusions or treating anaphylaxis in cancer patients should be aware of this life-threatening potential complication.

Acute Disease↗

PubMed1988

Myelopathy in AIDS. A clinical and electrophysiological study of 23 Danish patients.

In a cross-sectional population study of Danish patients with AIDS 16 of 23 had clinical signs of neurological disease with muscle weakness or ataxia of the lower limbs as the dominant manifestation. Tibial and median nerve conduction was mildly slowed in a few patients and 15 had widening of cerebral ventricles at CT. However, all had prolonged latency of cortical evoked response following tibial nerve stimulation mainly due to slowing through the spinal cord. The prolongation of the latency of the evoked cortical responses was most pronounced in patients with lower limb ataxia and/or paresis. It is concluded that affection of the long tracts of the spinal cord are closely associated with the human immunodeficiency virus infection.

Acquired Immunodeficiency Syndrome↗

PubMed1988

Use of single photon emission computed tomography (SPECT) to study the distribution of 90Y in patients with Baker's cysts and persistent synovitis of the knee.

The presence of a Baker's cyst may diminish the therapeutic effect of intra-articular 90Y treatment to the knee joint. SPECT (single photon emission computed tomography) was used in 10 patients with Baker's cysts, treated with intra-articular 90Y for persistent synovitis of the knee, to measure the amount of radioisotope within the cyst. Comparison was made with the arthrographic appearances. The likelihood or extent of uptake into Baker's cysts of 90Y injected into the synovial cavity of the knee was not predictable from arthrograms. Deposition of 90Y in cysts was variable, ranging from little or no measurable uptake to a substantial proportion of the administered activity (40% in one case out of 10). It did not appear to relate to clinical response. The low mean uptake (6.3%) in cysts of nine out of 10 patients was probably insignificant in view of the large uncertainty in the prediction of synovial radiation dose.

Humans↗

PubMed1988

Effects of electrostatic charge on the pathogenicity of chrysotile asbestos.

Two groups of 48 rats of the AF/HAN strain were exposed for one year to respirable dust clouds of UICC chrysotile asbestos at a dose level of 10 mg/m3. One group was treated with dust carrying the normal electrostatic charge produced during dust generation, whereas the other was exposed to dust discharged by exposure to ionising radiation from a thallium-204 source. After dusting most animals were retained for their full life span. At the end of the dusting period those animals treated with normally charged dust had significantly more chrysotile retained in their lungs than animals exposed to discharged dust. Subsequently, animals treated with normally charged dust developed more pulmonary fibrosis and more pulmonary tumours. These findings suggest that the charge carried by airborne fibres should be taken into account when considering the health risks from exposure to chrysotile. Highly charged fibres are more likely to be deposited in lung tissue and thus constitute a greater hazard.

Animals↗

PubMed1988

Adjuvant cyclophosphamide, doxorubicin, and cisplatin chemotherapy for bladder cancer: an update.

Seventy-one patients received adjuvant Cytoxan (cyclophosphamide; Bristol-Myers Co, Evansville, IN), Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), and cisplatin (CISCA) chemotherapy between March 1981 and March 1986. Patients received adjuvant CISCA chemotherapy if they had pathological findings that were thought to predict for high likelihood of relapse. These included the presence of resected nodal metastases, extravesicular involvement of tumor, lymphatic/vascular permeation of the primary tumor, or pelvic visceral invasion. Sixty-two patients at a similar high risk for recurrence did not receive adjuvant CISCA chemotherapy because they refused, had medical contraindications to therapy, or were not referred for chemotherapy. Two-hundred six patients had a cystectomy performed during the same study period but had none of the poor prognostic features suggesting a high risk for relapse. Sixty-two percent of the patients receiving adjuvant chemotherapy are alive and disease-free for a mean follow-up of 118 weeks (range, 28 to 310 weeks). A survival advantage exists for the adjuvant-treated patients when compared with those with unfavorable pathological findings who did not receive adjuvant chemotherapy (70% v 37%) (P = .00012): no difference exists in long-term disease-free survival for those with favorable pathological findings (long-term disease-free survival 76%) v those who received adjuvant chemotherapy (70%) (P = .33). Adjuvant CISCA chemotherapy prolongs the disease-free survival of some patients following a cystectomy. Patients who benefitted from adjuvant CISCA chemotherapy included those with resected nodal metastases, extra-vesicular involvement of tumor, and direct invasion of the pelvic viscera. Patients not benefitting from adjuvant CISCA chemotherapy in this analysis included those with lymphatic/vascular invasion in their primary tumor as the sole manifestation of high risk for relapse.

Antineoplastic Combined Chemotherapy Protocols↗