Lichenoid skin lesions as a sign of beta 2-microglobulin-induced amyloidosis in a long-term haemodialysis patient.

We report a case of beta 2-microglobulin-induced amyloidosis. The patient was a 40-year-old man suffering from non-amyloid nephropathy, who had been treated by haemodialysis for 20 years. Lichenoid skin lesions, consisting of groups of pin-head-sized shiny papules, were present on the arms and trunk. On histological examination, amyloid deposits were present, principally in the dermal papillae, but also around the sweat ducts and hair follicles. The amyloid displayed potassium-permanganate-resistant Congo red affinity, and green birefringence under polarized light. Immunohistochemically, beta 2-microglobulin was demonstrated in the lesions, confirming that they were a manifestation of beta 2-microglobulin-associated amyloidosis. Skin lesions of this type have not been reported previously in beta 2-microglobulin-associated amyloidosis.

Latent herpes simplex virus type 1 in human vestibular ganglia.

Viral infection has been considered to be a possible pathogenesis of vestibular neuronitis, and reactivation of the herpes simplex virus (HSV) is one of the most likely causes. However, it remains unknown whether the human vestibular ganglia contain latent HSV. We examined 26 vestibular ganglia from autopsied adults in search of HSV type 1 (HSV-1). To detect HSV-1, we used polymerase chain reaction (PCR), in situ hybridization and immunohistochemical staining. HSV DNA was detected in 6 of 10 vestibular ganglia using the PCR method. However, the latency-associated transcript (LAT) of HSV-1 was negative in all of the 16 vestibular ganglia examined. No HSV antigen was detected in any of the ganglia. These results indicate that HSV-1 is latently infected in the human vestibular ganglia, and that LAT is transcribed weakly or not at all.

Detection of latent herpes simplex virus DNA and RNA in human geniculate ganglia by the polymerase chain reaction.

By using the polymerase chain reaction (PCR) we detected latent herpes simplex virus type 1 (HSV-1) in human geniculate and trigeminal ganglia obtained from autopsy cases. A pair of primers which were specific for a part of the HSV-1 thymidine kinase domain were used for detection of HSV DNA. We also examined the latency-associated transcript (LAT), known as latency-specific RNA, by means of reverse transcription-PCR with a pair of LAT-specific primers. HSV-1 DNA was detected in 16 of 17 (94%) trigeminal ganglia and in 15 to 17 (88%) geniculate ganglia of adults. We also demonstrated HSV-1 RNA derived from the LAT in both types of ganglia. These findings suggest that HSV-1 latently infects the majority of geniculate and trigeminal ganglia of adults, and that PCR and reverse transcription-PCR are useful tools for analysis of HSV latency.

Triple cancers in the urogenital area of a patient with aplastic anemia.

Three epithelial neoplastic lesions, perineal Bowenoid papulosis, uterine cervical carcinoma, and bladder transitional cell carcinoma, which occurred in a mildly immunosuppressed patient who had aplastic anemia were studied for human papillomavirus (HPV) infection. In the Bowenoid papulosis, HPV type 16 DNA was identified by polymerase chain reaction (PCR) and by in situ hybridization (ISH). In contrast, in the uterine cervical carcinoma, HPV 16 was not detected, although possibly another unidentified type of HPV in the lesion was suggested by the ISH findings. In the bladder transitional cell carcinoma, neither papillomavirus genus-specific (PGS) antigen nor HPV DNA was found.

Effects of novel synthesized retinobenzoic acid (Am-80) on adenylate cyclase and arachidonic acid release in pig epidermis.

It has been well established that the psoriatic hyperproliferative epidermis is characterized by a defective beta-adrenergic adenylate cyclase response and an increased arachidonic acid metabolism. Effects of a newly synthesized retinoid, Am-80 (4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)amino) carbamoyl]benzoic acid), on the beta-adrenergic adenylate cyclase response and on the arachidonic acid metabolism of pig epidermis were investigated. Am-80 augmented the beta-adrenergic adenylate cyclase response of the epidermis. The effect was observed at the concentrations of more than 1 microM. The maximum beta-adrenergic augmentation effect induced by Am-80 was similar to those of all-trans-retinoic acid and of hydrocortisone. Am-80 inhibited the basal arachidonic acid release as well as 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated arachidonic acid release from epidermal keratinocytes. The effect was observed at the concentrations of 50-100 microM. The inhibitory effect of Am-80 was similar to those of all-trans-retinoic acid and of hydrocortisone. Our results indicate that Am-80, a newly synthesized retinoid, reveals the beta-adrenergic adenylate cyclase response augmentation effect and the inhibitory effect on the arachidonic acid metabolism of the epidermis. These effects are consistent with a view that Am-80 is another retinoid which has significant pharmacological effects on keratinocytes.

An association of acanthosis nigricans and Crouzon syndrome.

An 11-year-old Japanese female having acanthosis nigricans associated with Crouzon syndrome is reported. Crouzon syndrome is a craniostenotic craniofacial malformation associated with premature closure of selective calvarial sutures, exophthalmos, maxillary hypoplasia, and a beak-shaped nose. It is an autosomal dominant inherited disorder. Crouzon syndrome is one of the syndromes which may be associated with acanthosis nigricans. The association of acanthosis nigricans with Crouzon syndrome is assumed to be a rare abnormality, although the true frequency is uncertain. We have reviewed the reported cases of acanthosis nigricans associated with Crouzon syndrome and characteristics were discussed.

Latent herpes simplex virus type 1 in human geniculate ganglia.

Viral infection, especially by reactivation of herpes simplex virus (HSV) has been considered to be a possible explanation for the pathogenesis of idiopathic peripheral facial nerve palsy (Bell's palsy). We investigated whether the geniculate ganglia of man contain latent HSV type 1 (HSV-1), and compared the frequency of HSV-infected ganglia and that of latently infected neurons in human geniculate ganglia and in trigeminal ganglia. From autopsy specimens of eight adults 15 geniculate ganglia and 16 trigeminal ganglia were examined by means of in situ hybridization and immunohistochemical staining. The HSV-1 genome was detected in 11 of the 15 (71%) geniculate ganglia and in 13 of the 16 (81%) trigeminal ganglia. No HSV antigen was noted in any of the ganglia. The incidence of latently infected neurons was 0.9% in the trigeminal ganglia and 5.3% in the geniculate ganglia. The difference in percentages between the two types of ganglia was significant. Our results suggest that reactivation of latent HSV in the geniculate ganglia is a probable cause of some cases of herpetic stomatitis and of idiopathic peripheral facial nerve palsy.

Digit-muscle responses evoked from multiple intracortical foci in monkey precentral motor cortex.

1. The precentral motor cortex, including the anterior bank of the central sulcus of monkey (Macaca fuscata), was systemically penetrated with microelectrodes to determine the spatial organization of the microexcitable cortical elements that can produce responses in digit muscles. 2. At 200-microns intervals on each electrode track, low-current intracortical microstimuli were delivered and the muscle responses evoked from four digit muscles were recorded. The responses, obtained with 5, 8, 15, and 25 microA, were quantified and plotted on a map displaying an unfolded view of the precentral gyrus. 3. For all four muscles studied [first interosseus, thenar, extensor digitorum communis (EDC) and flexor digitorum profundus (FDP)], the effective stimulus points evoking muscle responses at a current of 5 microA were scattered over wide areas. The low-threshold foci, largely buried in the anterior bank of the central sulcus but partly extending to a region rostral to the sulcus, were found in multiple spots separated by a few millimeters. 4. Stimulation of individual sites at a current of 5 microA often evoked responses in several different muscles. Antagonist muscles were frequently coactivated. 5. A three-dimensional display of the distribution of response magnitude evoked from the precentral cortex indicates several peaks for each digit muscle. The peaks were either sharply demarcated from surrounding areas of minimal responses or gradually shifted into regions of low-grade responses. 6. Taken together, the data suggest that the digit area of motor cortex does not have a simple organization in which each muscle is represented by a single focus. Rather, each muscle has multiple foci that have varying degrees of efficacy in producing responses and with variable overlap onto foci of other muscles.

Neuronal activity in cortical motor areas related to ipsilateral, contralateral, and bilateral digit movements of the monkey.

1. Single cell activity was studied in the precentral (PCM), premotor (PM), and supplementary (SMA) motor cortex of the monkey to compare magnitudes of activity changes in relation to ipsilateral, contralateral, and bilateral digit movements. 2. Three Japanese monkeys were trained to press a small key with the right or left hand, or with both hands, in accordance with visual instruction signals given 2.6-5.4 s before a visual movement-trigger signal. Great care was taken to train the animal to use only the required part of the limb. As a result of extensive training, electromyographic (EMG) studies revealed that muscle activities before the key press were limited to the digit and hand muscles of the limb instructed to move. No overt increase or decrease in activity was detectable in the proximal limb or body muscles in relation to the key-press movements or instructions. 3. Even though the movement was thus limited to distal forelimb, distinct ipsilateral relationships were observed in 8.2% of the task-related PCM neurons. They changed their activity before ipsilateral and bilateral (but not before contralateral) key press. 4. A majority of the neurons recorded from the digit area of PCM (mostly limited to the anterior bank of the central sulcus) exhibited a contralateral relationship; namely the activity increased or decreased before the onset of the contralateral and bilateral key-press movements. In most of them, the magnitudes of the activity changes before the contralateral and bilateral movements were similar. 5. In proximal limb and trunk areas of PCM and also in the somatosensory cortex, no neurons were found to exhibit distinct relations to any of the key-press movements. 6. In both SMA and PM, a number of neurons exhibited relationships of the type never or only rarely observed in the primary motor cortex. Thirty-seven percent of SMA and 62% of PM neurons exhibited premovement activity changes before all of the key-press movements. The movement-specific type of activity was observed in 28% of SMA and 16% of PM neurons. In these neurons, the activity changes were observed in relation to only one of the right or left key-press movements or exclusively in relation to the bilateral key press. Neuronal activity resembling the majority of the PCM neurons (contralateral type) was observed in 31% of SMA and 13% of PM neurons. 7. Instruction-induced changes in activity were more often found in the secondary than in the primary motor area.(ABSTRACT TRUNCATED AT 400 WORDS)

Relation of neurons in the nonprimary motor cortex to bilateral hand movement.

In the primate cerebral cortex there are at least two somatotopically organized, nonprimary motor fields rostral to the primary motor area. To understand the functions of these multiple motor representations we have compared the neuronal activity in each of these fields while monkeys performed a trained motor task, using right, left or both hands. In the nonprimary motor cortex, activity in a number of neurons was related to the movement the animal chose and performed, whereas in the primary motor cortex, changes in the firing of most neurons were simply related to activity in the contralateral muscles. This result indicates that the nonprimary motor cortex is involved in higher-order coding of the laterality of the motor response, implying that it exerts its motor control function at a higher hierarchical level than its counterpart in the primary motor cortex.