IRBP: preparation and characterization of site-specific monoclonal antibodies.

Interstitial retinoid binding protein (IRBP) is a 136,000 molecular weight photoreceptor cell protein which is a highly pathogenic autoantigen for the induction of experimental autoimmune uveitis (EAU). In this study we produced a series of monoclonal antibodies (MAbs) which define different epitopes in the native molecule. These MAbs were further subdivided into three distinct groups based on a radioimmunoassay, and by ELISA assay using native IRBP and synthetic peptides corresponding to its entire amino acid sequence. Group I MAbs (MAbD7-B1 and MAbC6-B4) bound to native IRBP but not to any synthetic peptides, suggesting that their antigenic epitopes are strictly conformation dependent. Group II MAbs (MAbC7-D3 and MAbG8-H4) bound weakly to multiple peptides which shared amino acid sequence similarity located within each of four homology domains indicating that these epitopes are also conformation dependent. In group III (MAbH3-B5, MAbH7-A5, and MAbB6-D12) MAb binding was localized to a specific peptide. The MAbH3-B5 binding site was further refined to amino acid positions 361 to 367 in the native molecule. MAbH3-B5 was also useful in localizing IRBP in the mouse retina by immunohistochemical techniques. The application of these MAbs in the study of EAU and interphotoreceptor transport mechanisms is discussed.     

Treatment of muscle spasticity in patients with cerebral palsy using BTX-A: a pilot study

This study was designed to verify the safety and efficacy of botulinum toxin type A (BTX-A) used as a neuromuscular block on spastic masticatory musculature of children with cerebral palsy. Six patients who had spastic-tetraplegic cerebral-palsy, aged 5 to 20 years were selected. All patients had spasticity of the jaw muscles, bruxism, lower lip trauma, limited mouth opening, and difficulties in cleaning the oral cavity. The patients were sedated under general anesthesia, while the dentist injected the masseter and temporalis muscles bilaterally with 150 and 75 units of BTX-A each. Clinical examinations were conducted at 7, 14, 30, and 90 days after the initial appointment. We found statistically significant decreases in muscle spasticity and bruxism ( p = 0.002), improved inter-incisal opening ( p = 0.002), improved oral hygiene ( p = 0.031), and less lower lip trauma ( p = 0.060) after the neuromuscular blocking.     

Retinoblastoma. A clinical, immunohistochemical, and electron microscopic case report

A 4-year, 9-month-old boy had a history of leukocoria of the right eye for approximately six months prior to admission. The other eye was normal. There was no family history of retinoblastoma. Funduscopy disclosed a large white mass extending from the nasal pars plana to the mid-pupillary zone and the posterior pole with a near total retinal detachment in the superior temporal quadrant. A B-scan ultrasound showed an echo dense area of the anterior portion of the mass. A CT scan showed intraocular tissue densities with no evidence of optic nerve involvement or extraocular extension. Immunohistochemistry of a fresh frozen portion of tumor revealed reactivity with antibodies directed against interphotoreceptor retinoid-binding-protein (IRBP), neuron-specific enolase, glial fibrillary acidic protein, S-antigen, focal reactivity with opsin, and scattered cytoplasmic staining for cyclic GMP and cyclic GMP phosphodiesterase. Biochemical analysis of fresh frozen tissue samples confirmed the presence of IRBP. Transmission electron microscopy disclosed occasional Flexner-Wintersteiner rosettes connected by zonula adherens-like junctions. These showed inner segment-like structures containing prominent mitochondria, portions of cilia and fragments of outer segment material. These data, along with the immunocytochemistry indicates a predominant neuronal nature of the tumor cells with significant photoreceptor-like differentiation.     

Variability in cardiovascular and plasma norepinephrine responses to head-up tilt in healthy human subjects.

Eight healthy, young adult males underwent three separate, 10-min 70 degrees head-up tilts (HUT) over a period of nine days, in order to assess the intra- and inter-individual variability of cardiovascular and plasma norepinephrine (NE) responses to the manoeuvre. Cardiovascular parameters and plasma NE were measured in the basal state and at 2-min intervals during the HUT. The results indicate that: (1) the intra-individual variability is a smaller component of the total variability of both cardiovascular and plasma NE responses to HUT; (2) the variability in cardiovascular parameters is smaller than that in plasma NE levels, both basal and in response to postural stress; (3) there does not appear to be any difference in variability when expressed either as the maximal or the mean response to HUT; and (4) there does not appear to be an increase in the variability of the measured parameters over the duration of the HUT.     

Clinico-microbiological study of dermatophytoses.

In the present series, 80 cases of dermatophytoses were subjected to mycological examination including microscopy and culture the mycological findings were correlated with clinical presentation of the patients. The isolation rate was 62.5 percent. Fungal culture was successful in 36.25 percent of cases, Trichophyton rubrum being the commonest etiological agent accounting for 55.18 percent of cases.     

Ictal chronology and interictal spikes predict perfusion patterns in temporal lobe epilepsy: a multivariate study.

Typical (TPP) and atypical (APP) perfusion patterns (PP) may be seen in ictal SPECT of patients with temporal lobe epilepsy (TLE). APP may pose problem in the lateralization of the epileptogenic zone (EZ). We aimed to investigate predictive variables for the occurrence of TPP and APP. Fifty-one TLE patients were submitted to successful anterior-mesial temporal lobectomy. Univariate (UVA) and multivariate (MVA) analysis were performed upon clinical data, distribution of interictal spikes, and ictal chronology of seizures. From MVA, a final predictive model (FPM) was determined to better predict TPP and APP. Forty patients showed TPP (78.5%) and 11 patients APP (21.5%). Accuracy of ictal SPECT was higher in the unilateral (UIS) than in the bilateral (BIS) interictal spikes group (P = 0.05). FPM showed that patients exhibiting BIS, with shorter proportion of the electrographic seizure occurring after completion of tracer injection, and longer clinical than EEG seizure duration had more APP (P = 0.003). Generalized tonic-clonic seizures did not result in more APP. We concluded that analysis of ictal SPECT in TLE requires the knowledge of TPP and APP, the distribution of interictal spikes on temporal lobes and the ictal chronology of seizures. BIS showed that beyond a more complex epileptogenicity and seizure propagation, they may also lead to APP.     

Extended pericranial flap and bone graft reconstruction in anterior skull base surgery.

OBJECTIVES: The objectives of this study was to establish a rationale for repairing large anterior skull base defects with an extended pericranial flap and split calvarial bone graft; to define large anterior skull base defects as those spanning the anterior cranial measuring at least 3.0 x 4.0 cm; and to describe the surgical technique and compare it with alternative strategies.Study design Thirty-four patients underwent anterior craniofacial resection of anterior skull-based tumors of varying histology with reconstruction using an extended pericranial flap and split calvarial bone graft. RESULTS: The survival of the pericranial flap and bone graft was maintained in 33 of 34 patients. There was 1 episode of postoperative cerebrospinal fluid leak, 1 episode of osteomyelitis of the bone graft and an epidural abscess, and 1 episode of asymptomatic pneumocephalus. CONCLUSION: Split calvarial bone graft with an extended pericranial flap is an effective technique for reconstructing large anterior skull base defects.     

Ki-1 Large Cell Lymphoma with Regressing Lesions in a Child

An 8-year-old boy was seen with a cutaneous Ki-1 anaplastic, large cell lymphoma with multiple lesions. Some of the lesions showed spontaneous regression. During more than seven years of disease no systemic involvement was observed, but recurrent, self-healing lesions did appear. Histopathologic examination of five lesions revealed a variety of findings, from an inflammatory infiltrate to a highly anaplastic pattern. The neoplastic cells expressed Ki-1 and leukocyte common antigens. Ultrastructurally, those cells showed ruffled indentations. The differential diagnosis includes microvillous malignant lymphoma. The patient has had a four-year follow-up without relapses.     

Salmonellosis in Goa.

During the period 1982-86, a total of 657 Salmonella strains were isolated from various clinical samples processed in the Microbiology laboratory of Goa Medical College, Bambolim, Goa. The strains were distributed amongst 23 different Salmonella serotypes. The commonest serotypes encountered were S.typhimurium (66%) and S.typhi (24%), the other serotypes were S.bareilly (5.4%), S.paratyphi B (1.2%), S.newport (1.2%) and S.chester (0.8%). Stool samples yielded the maximum Salmonella isolates of which the S.typhimurium was the highest followed by S.bareilly.     

Space time clustering of births in SIDS: do perinatal infections play a role?

The aetiology of sudden infant death syndrome (SIDS) remains uncertain; many causal pathways have been proposed. In this paper we have examined firstly the variation in the risk of SIDS with age, month of death and month of birth; and secondly the space time clustering of SIDS deaths, and, separately, space time clustering of their births. Data were obtained from the Office of Populations, Censuses and Surveys on all certified SIDS deaths in the period; children were assigned grid references for the address of birth and of death. Data on number of births were abstracted from published material. A log-linear modelling technique was used to investigate the separate effects of age, month of death and month of birth on the risk of SIDS. The Knox method was used to investigate space time clustering of deaths and of births of children who died of SIDS. Separate, statistically significant effects were found for age, month of death and month of birth. There was minor space time clustering of SIDS births and deaths at large time and space intervals, and a marked space time clustering of births in short space time intervals in the first quarter of the year. The finding of an effect of month of birth on the risk of SIDS, and of space time clustering of births suggest that a perinatal hazard--possibly of infectious origin--may play a role in the aetiology of SIDS.