Neuropsychological changes following electrical injury.

The clinical presentation of electrical injury commonly involves physical, cognitive, and emotional complaints. Neuropsychological studies, including case reports, have indicated that electrical injury (EI) survivors may experience a broad range of impaired neuropsychological functions, although this has not been clarified through controlled investigation. In this study, we describe the neuropsychological test findings in a series of 29 EI patients carefully screened and matched to a group of 29 demographically similar healthy electricians. Participants were matched by their estimated premorbid intellectual ability. Multivariate analysis of variance was used to assess group differences in the following neuropsychological domains: attention and mental speed, working memory, verbal memory, visual memory, and motor skills. EI patients performed significantly worse on composite measures of attention/mental speed and motor skills, which could not be explained by demographic differences, injury parameters, litigation status, or mood disturbance. Results suggest that cognitive changes do occur in patients suffering from electrical injury.     

Xanthogranulomatous orchitis: Review of the published work and report of one case

Xanthogranulomatous orchitis is an extremely rare inflammatory non-neoplastic destructive lesion of the testis. We report a 44-year-old man who presented with right scrotal swelling and two discharging sinuses. Testicular tumor markers were normal. Scrotal ultrasound showed heterogeneous testicular areas and irregular margin of the tunica. Surgical exploration revealed infected, unhealthy testicular tissue with necrosis and tumor-like lesion. Orchidectomy was done and histopathology showed xanthogranulomatous orchitis.     

Impaired in-vitro proliferation of hemopoietic precursors in HIV-1-infected subjects

Patients with acquired immunodeficiency syndrome (AIDS) and persistent lymphadenopathy syndrome (LAS) display significant hematological abnormalities of one or more cell lineages. In order to understand the pathophysiologic mechanisms leading to these abnormalities we studied the proliferation capacity of pluripotent and committed hemopoietic precursors using in-vitro colony assays. Anemia, leukopenia and thrombopenia were relatively frequent findings in HIV-infected subjects irrespectively of the patients' clinical status. The colony growth capacity of AIDS patients' GM-CFU and BFU-E was significantly decreased whereas no GEMM-CFU colonies could be obtained. There was no correlation between the number of BFU-E and GM-CFU colony number and the hemoglobin or the absolute number of polynuclear cells, respectively. The plating efficiency of both committed and pluripotent hematopoietic precursors from HIV infected patients could not be enhanced when additional exogenous recombinant GM-CSF, human interleukin 3 or erythropoietin were added in contrast to normal patients' cells. In addition, the impaired colony growth of these precursors could not be restored after adherent or T-cell depletion or the addition of normal allogenic irradiated adherent or/and T cells. Since this colony growth abnormality was also detected in HIV seropositive asymptomatic subjects our findings strongly suggest that the in-vitro growth of hematopoietic precursors is affected early after HIV-1 infection.     

Lack of apparent receptor reserve at postsynaptic 5-hydroxytryptamine1A receptors negatively coupled to adenylyl cyclase activity in rat hippocampal membranes.

Previous studies have demonstrated the existence of a large receptor reserve for agonists at somatodendritic 5-hydroxytryptamine1A (5-HT1A) serotonin receptors in the raphe nuclei of the rat. 5-HT1A agonists with anxiolytic properties (e.g., buspirone, gepirone, and ipsapirone) display full intrinsic activity at these receptors but are partial agonists at postsynaptic 5-HT1A receptors, which suggests that the latter sites may be devoid of a receptor reserve. In the present studies, this was directly determined by examining the relationship between receptor occupancy and response at postsynaptic 5-HT1A receptors, in rat hippocampus, mediating the inhibition of forskolin-stimulated adenylyl cyclase activity, using the method of partial irreversible receptor inactivation. Rats were treated with vehicle or the irreversible antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ), and 24 hr later hippocampi were removed for saturation analysis of [3H]8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT) binding to 5-HT1A receptors or for adenylyl cyclase assays. EEDQ (1 and 6 mg/kg) dose-dependently reduced the maximal number of [3H]8-OH-DPAT binding sites by 68.5 and 80%, respectively, without altering the Kd. Concentration-response curves were generated for inhibition of forskolin-stimulated adenylyl cyclase activity by 5-HT and the selective 5-HT1A agonist N,N-dipropyl-5-carboxamidotryptamine (DP-5-CT). EEDQ treatment dose-dependently reduced the maximal inhibitory effect of 5-HT [percentage of inhibition: control, 23.6; EEDQ (1 mg/kg), 13.4; EEDQ (6 mg/kg), 8.9], without altering either the slope factor (1.01) or the EC50 (96.4 nM). Analogous results were obtained with DP-5-CT [percentage of maximal inhibition: control, 24.1; EEDQ (1 mg/kg), 15.2; EEDQ (6 mg/kg), 10.7), again without changes in slope factor (0.89) or EC50 (9.9 nM). Analysis of double-reciprocal plots of equieffective concentrations of agonist, followed by calculation of fractional receptor occupancy, revealed a linear relationship between receptor occupancy and response for both 5-HT and DP-5-CT (i.e., an absence of receptor reserve). The receptor specificity of the effect of EEDQ was demonstrated in two ways. First, it was shown that pretreatment of rats with the selective 5-HT1A partial agonist BMY 7378 (10 mg/kg) before EEDQ afforded substantial protection (about 75%) against loss of the inhibitory effect of DP-5-CT on forskolin-stimulated adenylyl cyclase activity. Second, EEDQ did not alter the inhibition of forskolin-stimulated adenylyl cyclase activity induced by the adenosine A1 receptor agonist phenylisopropyladenosine (PIA).(ABSTRACT TRUNCATED AT 400 WORDS)     

Brain abscess in Saudi Arabia

There are significant variations among countries in the incidence of brain abscess. We report here 26 cases of brain abscess treated at the Neurosurgery Department of King Faisal University and Dammam Central Hospital Saudi Arabia over a six year period (1982–1988). This is 2.3% of total admissions to the two neurosurgery departments serving a population of approximately 1.2 million in the same period.Young males were most often affected (M/F ratio 3.3:1; 31% were less than 15 years old, 46% aged between 15–39 years, and 23% older than 40 years). Streptococcus was found to be the most common microorganism (38.4%). Mixed infection was seen in 15.3%, and sterile abscesses were found in 11.5% of the patients after aerobic and anaerobic cultures of the pus. Chronic otitis media and paranasal sinusitis predisposed the patients to abscess formation in 57.6% of the cases. The temporo-parietal area was the commonest site. Epilepsy was a complication in 30.7% of our patients, and the mortality rate was 15.3%.     

Correlation of carotid artery stump pressure with a palpable carotid artery pulse.

The carotid artery stump pressure has been used as a criterion for selective placement of a shunt during carotid endarterectomy. The purpose of our study was to correlate the carotid stump pressure with the presence or absence of a palpable pulse in the carotid stump. One hundred twenty-two consecutive patients undergoing carotid endarterectomy under general anesthesia were checked for a palpable pulse in the internal carotid stump with subsequent measurements of the stump pressure. Of these patients, 88 had a palpable pulse and a pressure greater than or equal to 44 mmHg. The remaining 34 had a absent pulse and a stump pressure of 40 mmHg or less. Shunts were not used in those patients with a palpable pulse and no history of previous stroke or contralateral carotid occlusion. There were no serious neurological complications. We conclude that the presence of a palpable pulse in the carotid stump is a sufficient criterion for performing carotid endarterectomy without a shunt in those patients with no previous history of stroke or contralateral carotid occlusion.     

Carotid Stent-Supported Angioplasty via Radiobrachial Route

Endovascular stent-supported angioplasty is a treatment option for atherosclerotic disease of the cervical internal carotid artery in high-risk patients. The traditional transfemoral approach is not suitable for patients who suffer from common femoral artery or abdominal aorta atheropathy. We report a case of carotid stent deployment using the radial route in a 68-year-old man with type B aortic dissection, having severe right internal carotid artery origin stenosis, presenting with ipsilateral retinal ischemic events. Technical aspects of carotid stenting via the radial approach are described and the related literature is discussed.     

The interferon antagonist sarcolectin in the progress of HIV-1 infection and in AIDS.

Sarcolectin (SCL) is a nonspecific stimulator of cellular DNA synthesis that was found in all animal sera tested to date. It inhibits the established interferon (IFN)-dependent antiviral state, restoring cells to their normal status. In this study, we examined the excretion/secretion of the IFN antagonist SCL in sera from healthy donors and in sera collected during different periods of human immunodeficiency virus type 1 (HIV-1) infection. We followed HIV-1-infected patients during all stages of development (seroconversion, initial and advanced phases of AIDS) and found a significant increase in SCL in sera of HIV-infected patients compared with seronegative subjects used as controls. This increase was established during seroconversion, and then the titers leveled off. In the final stage of the disease, the SCL titer increased again very significantly. We attribute this rapid rise to the virus-dependent destruction of T cells that can no longer be repaired. The high SCL level observed at this final stage, which is most predictive of the disease's progression, suggests that the action, rather than the production, of IFN is impaired.     

Receptors for neurohypophyseal hormones along the rat nephron: 125I-labelled d(CH2)5[Tyr(Me)2, Thr4, Orn8, Tyr-NH 2 9 ] vasotocin binding in microdissected tubules

A microassay was developed to measure the binding of the labelled monoiodinated analogue [1-(mercapto-,-cyclopentamethylenepropionic acid), 2-O-mithyltyrosine, 4-threonine, 8-ornithine, 9-¹²⁵I-tyrosylamide]vasotocin ¹²⁵I-d(CH₂)₅[Tyr (Me)², Thr⁴, Tyr-NH ₂ ⁹ ]OVT to isolated nephron segments microdissected from collagenase-treated rat kidneys. When determined using 1.7 nM labelled ligand at 4° C, specific binding sites (expressed at 10^–18 mol ¹²⁵I-d(CH₂)₅[Tyr (Me)², Thr⁴, Tyr-NH ₂ ⁹ ]OVT bound/mm tubule length) were found in medullary thick ascending limbs (MTAL), 1.67±0.49; cortical thick ascending limbs, 2.20±0.80; cortical collecting ducts, 2.39±0.86; outer medullary collecting ducts (OMCD), 2.54±0.53 and inner medullary collecting ducts, 5.33±0.40, whereas no specific binding could be detected in glomeruli and proximal tubules. Specific ¹²⁵I-d(CH₂)₅[Tyr (Me)², Thr⁴, Tyr-NH ₂ ⁹ ]OVT binding to OMCD was saturable with incubation time and reversible after elimination of free labelled ligand (the association and dissociation rate constants at 4° C were 1.06×10⁷ M^–1 min^–1 and 1.95×10^–2 min^–1 respectively). The stereospecificity of MTAL and OMCD binding sites was assessed in competitive experiments revealing the following recognition pattern for a series of eight vasopressin analogues:ddAVP>AVP>d(CH₂)₅-[Tyr (Me)², Thr⁴, Tyr-NH ₂ ⁹ ]OVT=AVT=OT>d(CH₂)₅[Tyr(Me)²]AVP=[Thr⁴, Gly⁷]OT>[Phe², Orn⁸]VT, whereas pharmacological concentrations of insulin and glucagon did not impair radioligand binding. These results indicate that the detected labelled binding sites might correspond mainly to physiological V₂ vasopressin receptors.