Aspergillotic aneurysm formation of cerebral artery following neurosurgical operation

A rare case of intracranial aspergillotic aneurysm following neurosurgical operation for facial spasm is presented. Severe meningitis had persisted several days prior to the subarachnoid hemorrhage which occurred on 70th postoperative day. Angiography demonstrated a fusiform aneurysm at the peduncular segment of the superior cerebellar artery on the other side of operation. As the repeated cultures of CSF were negative, the pathogenetic factor causing aneurysm formation could not be identified before second operation of aneurysmal resection. Pathological study of the specimen revealed the arterial wall being deeply invaded by aspergillotic hyphae.

Risk factors for brain abscess in patients with congenital cyanotic heart disease

Brain abscess is a serious complication of congenital cyanotic heart disease. We retrospectively evaluated the risk factors for brain abscess in 21 such patients treated between 1975 and 1990 in comparison with a control group. The mean arterial oxygen saturation, arterial partial pressure of O2, arterial blood oxygen content, and base excess in patients with brain abscess were significantly lower than in the control patients. The mean arterial partial pressure of CO2, pH, hematocrit, hemoglobin, and red blood cell content in patients with brain abscess were not significantly different. Patients with congenital cyanotic heart disease may develop minute encephalomalacia due to severe hypoxemia and increased blood viscosity resulting from compensatory polycythemia. The increased blood viscosity and reduced blood flow in the microcirculation may induce cerebral thrombosis or exaggerate minute encephalomalacia during dehydration or cardiac dysfunction, and shunted blood containing infectious organisms at such sites may be followed by focal cerebritis.

Antitumor effect of RBS (rice bran saccharide) on ENNG-induced carcinogenesis

We examined whether orally administered RBS (rice bran saccharide), prepared from rice bran by hot water extraction, increases immunocompetence, inhibits gastrointestinal carcinogenesis with N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) or shows an antitumor effect. After the administration of RBS, phytohemagglutinin (PHA)- and pokeweed mitogen (PWM)-stimulated blastogenesis of lymphocytes derived from the mesenteric lymph nodes and peripheral blood was enhanced, and the helper/suppressor T-cell ratio was elevated, and migration activity of peritoneal macrophages was also increased in rats treated continuously with ENNG. ENNG-induced gastrointestinal carcinomas were observed in 43% of those administered RBS (ENNG-RBS) as compared with 88% in the control (ENNG) and 94% in the prednisolone (PRD) group (ENNG-PRD). The 12-month survival rate of rats bearing gastrointestinal cancer was 58% in the ENNG-RBS group as compared with 25% in the ENNG group and 15% in the ENNG-PRD group. RBS prevented the reduction in immunocompetence in the course of carcinogenesis, suppressed carcinogenesis, and prolonged the survival of rats with gastrointestinal cancer. Antitumor activities of RBS are thought to be a kind of host mediated action. The growth inhibition ratio of transplantable ENNG-induced cancer in Wistar rats was 42.1% in the RBS and 51.8% in the 5-FU group. Since little is known about the potent antitumor activity of alpha-glucan, it would be interesting to consider the relationship between the structure and the biological activities of polysaccharides.

A case of histiocytic necrotizing lymphadenitis with bone marrow and skin involvement

We report a case of histiocytic necrotizing lymphadenitis (HNL) with bone marrow extension in a 29-year-old male in which many large mononuclear cells infiltrated the bone marrow and mimicked malignant lymphoma. A lymph node biopsy confirmed the diagnosis of HNL. Immunohistologically, the infiltrating cells in the bone marrow were positive for lysozyme, LeuM1, Kp-1 and T-cell markers. The cells did not show haemophagocytosis. A skin biopsy from an accompanying facial skin rash revealed a proliferation of large cells similar to those observed in affected foci of the lymph node in subcutaneous tissue. The infiltrating cells were mainly lysozyme and Kp-1-positive histiocytes, some with phagocytosis of nuclear debris but none characteristic of haemophagocytosis. Transformed T-cells were also infiltrating.

[Pharmacokinetics of epidurally administered bupivacaine during prostaglandin E1- or trimetaphan-induced hypotension]

The effects of prostaglandin E1 (PGE1) and trimetaphan (TMP) on the plasma concentrations and derived pharmacokinetic parameters of bupivacaine were studied in 14 women after its epidural administration. Patients, whose ages ranging from 35 to 60 years for mastectomy, received 50 mg of bupivacaine without epinephrine injected into the cervical epidural space during PGE1- or TMP-induced hypotension (80-90 mmHg of the systolic arterial pressure) under general anesthesia with nitrous oxide, oxygen and isoflurane 0.3-0.5%. No significant differences in pharmacokinetic parameters for the absorption and distribution of bupivacaine were found between the two groups. However, the mean elimination half-life of bupivacaine was significantly longer in patients with TMP [5.0 +/- 1.7 (SD) hr] compared with those with PGE1 (3.1 +/- 1.4 hr). The total clearance of bupivacaine was greater in patients with PGE1 (345 +/- 150 ml.min-1) compared with those with TMP (248 +/- 66 ml.min-1). The results of this pharmacokinetic study indicate that the plasma bupivacaine concentration decreases more rapidly during PGE1-induced hypotension than during TMP-induced hypotension.

Stabilization of human neutrophil NADPH oxidase activated in a cell-free system by cytosolic proteins and by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide

The superoxide-generating respiratory burst oxidase (NADPH oxidase) from human neutrophils can be activated in a cell-free system consisting of plasma membrane and cytosol by anionic amphiphiles such as sodium dodecyl sulfate and arachidonate (McPhail, L. C., Shirley, P. S., Clayton, C. C., and Snyderman, R. (1985) J. Clin. Invest. 75, 1735-1739; Curnutte, J. T. (1985) J. Clin. Invest. 75, 1740-1743; Bromberg, Y., and Pick, E. (1984) Cell. Immunol. 88, 213-221). Herein, the activity thus obtained is shown to be very labile at 37 degrees C. The rate of inactivation varied inversely with cytosol concentration. The stabilizing factor(s) was destroyed by heat and trypsin, indicating that it is protein in nature. Whereas cytosol from normal cells and from a chronic granulomatous disease patient lacking p67phox stabilized the oxidase activity, that from a chronic granulomatous disease patient lacking p47phox did not. Also, dialdehyde NADPH-treated cytosol showed no stabilizing effect, indicating that p47phox and a putative NADPH-binding component both participate in stabilization. The mechanism of inactivation was further explored by examining the stabilizing effect of agents that can act as chemical cross-linkers. Of several tested, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) was the most effective, but others that utilize different chemical mechanisms were also partially effective. EDC extended the half-life at 37 degrees C from 2 to 120 min, protected against the inactivating effects of Triton X-100 and high salt, and did not affect the Km for NADPH. Stabilization required prior activation in the presence of both cytosol and membrane; and EDC treatment of cytosol, membrane, or a mixture of the two prior to the addition of sodium dodecyl sulfate failed to induce stabilization. EDC eliminated the requirement for the continuous presence of cytosol and activator. Dialysis did not cause a loss in activity, whereas control activity was diminished with dialysis and was largely restored with added sodium dodecyl sulfate. In the absence of EDC, the separation of cytosol from the membrane fraction resulted in a significant loss of activity, which was largely restored by the addition of cytosol. However, EDC treatment allowed the isolation of a nearly fully active oxidase in the membrane fraction, the activity of which was not influenced by added cytosol. These results support a model in which the active NADPH oxidase consists of a dissociable complex among membrane and cytosolic components and indicate that the longevity of the activated state requires continuous association of these components.

Spermine down-regulates superoxide generation induced by fMet-Leu-Phe in electropermeabilized human neutrophils

Effect of spermine, a naturally occurring polyamine, was investigated on superoxide generation in intact and electropermeabilized human neutrophils. Spermine suppressed N-formyl-methionyl leucyl phenylalanine (fMLP)-induced superoxide generation in permeabilized cells by reducing the rate and shortening the duration time. The inhibition was specific for spermine comparing with its precursor amines, spermidine and putrescine. The inhibition was not observed when cells were preincubated with spermine without permeabilization. Concanavalin A-induced superoxide generation was also down-regulated by spermine in permeabilized cells, but the activation induced by non receptor-mediated agonist (dioctanoylglycerol, phorbol myristate acetate, and arachidonate) was not affected by spermine. On the other hand, GTP-gamma-S-induced activation of superoxide generation was substantially suppressed by spermine. These results indicate that spermine inhibition occurs at a step prior to protein kinase C in signal transduction or in a pathway which is independent of the kinase.

Human T-cell leukemia virus type I associated lymphadenitis

Histopathologic changes in lymph nodes were examined from ten patients with mild lymphadenopathy, a few atypical lymphocytes in their peripheral blood, skin lesions, and proviral DNA of human T-cell leukemia virus type I (HTLV-I) in their nodes. The proviral DNA of HTLV-I was detected by southern blot analysis, in situ hybridization, and/or polymerase chain reaction techniques. The lymph nodes showed preserved nodal architecture with diffuse infiltration of small to intermediate-sized lymphocytes in association with scattered transformed lymphocytes and a few immunoblast-like cells in the enlarged paracortex. The infiltrating lymphocytes were positive for CD4, but neither rearrangement nor deletion of T-cell receptors and immunoglobulin heavy chain genes was detected. Eight of ten patients received no therapy, and all patients were alive and healthy more than 5 months after the biopsies. The histologic findings resembled those of a viral infection and could be distinguished from HTLV-I associated lymphomas.

[The management of stage I lymphomas of the B-cell type with special reference to the role of radiation therapy]

Fifty-one patients with clinical stage I B-cell lymphomas were treated between 1980 and 1988. For the entire group, the actuarial 5-year survival rate and 5-year freedom from relapse rate were 78% and 64%, respectively. Primary site, tumor bulk and performance status were the prognostic factors. Twenty-three patients were intensively treated with local radiotherapy alone, because (1) they had histologically low grade (7 patients) or follicular large cell (1 patients) tumors, (2) Waldeyer's ring was the site of the primary (11 patients) or (3) the tumor was less than 4 cm in maximum diameter (4 patients). Among them, only one patient died due to lymphoma (5-year survival rate: 95%), and 19 remained disease free (5-year freedom from relapse rate: 80%). In contrast, of the remaining 23 patients treated with both radiation therapy and combination chemotherapy (VEMP or CHOP), the 5-year survival rate and 5-year freedom from relapse rate were 70% and 54%, respectively. These results suggest that high-risk patients should be treated with more aggressive combination chemotherapy as well as radiotherapy. However, low-risk patients with stage I B-cell lymphomas can be treated by local radiotherapy alone.

Immuno- and enzymehistochemical characterization of 'plasmacytoid T-cells' in formalin-fixed paraffin-embedded tissue of reactive lymph nodes

In eight (10.4%) of 77 randomly selected cases of lymphadenitis, foci of 'plasmacytoid T-cells' (PTCs) were found. We characterized the PTCs in formalin-fixed paraffin-embedded tissue by immuno- and enzymehistochemical techniques. In each case the PTCs formed nodular and patchy infiltration patterns around the high endothelial venules in the paracortex of the lymph nodes. The PTCs in half of the cases were present near the intermediary peritrabecular sinuses. The PTCs were found to be positive for CD 45 (LCA), CD 45 R (4 KB 5) and CD 43 (MT 1), but not for CD 45 RO (UCHL 1), L 26 (CD 20), myeloperoxidase, naphthol AS-D chloroacetate esterase, Mac 387, alpha-1-antichymotrypsin or S 100 protein and anti-dendritic reticulum cell antibody. Some lysozyme+ PTCs were mingled in and around the foci in each case. In five cases the PTCs showed weaker positive reactions for CD 68 (EBM 11) and HLA-DR than for T-zone macrophages and sinus histiocytes. Related to the degree of desintegration of the nodular PTC-foci increasing numbers of T- and B-lymphocytes, T-zone macrophages and interdigitating reticulum cells with HLA-DR were detected in the foci. In two cases, where there was no HLA-DR expression by PTCs, small amounts of HLA-DR in secondary lymph follicles and a decrease of HLA-DR+ T-zone macrophages and interdigitating reticulum cells were observed. Our results suggest that there is a high degree of interaction between PTCs and other cellular components in the lymph node. The PTC may represent a special type of resident macrophage with secretory capacities.

[ARDS-like reactive respiratory failure after radical operation for esophageal cancer--with reference to PMN elastase and anaphylatoxin]

In a study undertaken to elucidate the pathophysiology underlying reactive respiratory failure following surgery for esophageal cancer, postoperative esophageal cancer patients were divided into 2 groups, i.e. one with respiratory failure (defined as impairment of oxygenating capacity with a respiratory index (RI) value of 1.5 or above, lasting from more than 5 days after surgery) and the other without it, and between-group comparisons were made of respiratory & circulatory dynamics and biologic response system components, e.g., complement, anaphylatoxins and polymorphonuclear granulocytes (PMN) elastase. There were no differences between the two groups in patient's age at operation and pulmonary function test. The mean duration of endotracheal control was 5.1 days for the respiratory failure (+) group against 3.7 days for the respiratory failure (-) group. Assessments of respiratory & circulatory dynamics showed that the RI was significantly increase early in the postoperative course in the respiratory failure (+) group as compared with the respiratory failure (-) group, while the hydrostatic pressure of pulmonary circulation (pulmonary microvascular pressure (Pmv)-plasma colloid-osmotic pressure (COP] and pulmonary shunting rate (Qs/Qt) were also elevated in the former group. Among biologic response parameters, the leukocyte count, platelet count, CH5, C3, and C5 showed long-sustained decreases from the postoperative day 1 on in the repertory failure (+) group as compared to the respiratory failure (-) while PMN elastase activity and anaphylatoxin C3a were elevated from the postoperative day 1 on in the former group.(ABSTRACT TRUNCATED AT 250 WORDS)

Defective provirus form of human T-cell leukemia virus type I in adult T-cell leukemia/lymphoma: clinicopathological features

Human T-cell leukemia virus type I (HTLV-I) is associated with adult T-cell leukemia/lymphoma (ATLL). To examine the relationship between defective HTLV-I proviruses and clinicopathological features, we examined 95 patients with ATLL showing clonal integration of HTLV-I proviral DNA; 77 patients (81%) showed 1 clonal band, 15 (16%) showed 2 clonal bands, and 3 (3%) showed 3 clonal bands. In addition, the defective proviral form was detected in 28 patients (29%): 23 (30%) of the 77 with 1 clonal band, 4(27%) of the 15 with 2 clonal bands, and 1(33%) of the 3 with 3 clonal bands. The numbers of clonal bands had no association with the presence of defective proviruses. We classified the 95 patients with ATLL into four types according to clinicopathological features (smoldering leukemia, chronic leukemia, acute leukemia, and lymphoma types). The distribution of patients with the defective form was not different among these four types. The HTLV-I genomes must have integrated into the human genome DNA and been deleted partially in the cells. The defective form was kept during the clinical stage. All patients with the defective form showed defect of the gag or/and env region. No patient had a defect of the pX region. These data suggest that the pX region of HTLV-I must have played an important role in ATLL genesis.

[A case showing the infraoptic course of the anterior cerebral artery associated with anterior cerebral artery aneurysm]

A ruptured anterior cerebral artery aneurysm with anomalous right infraoptic course of the anterior cerebral artery (ACA) was reported. A 40-year old male was admitted because of SAH episode, and computerized tomography (CT) on the day of admission revealed hemorrhage in both Sylvian and interhemispheric fissures. Four-vessel angiography was performed on the same day. A saccular aneurysm was demonstrated in the region of the anterior communicating artery (ACoA), and anomalous artery, which originated from the intradural right carotid artery at the level of the right ophthalmic artery was found to be running medially and superiorly. It supplied the bilateral callosomarginal arteries and the unpaired pericallosal artery. The fenestration of the vertebral artery, duplication of bilateral superior cerebellar arteries, and an occipital artery arising from the right internal carotid artery at the C3 level were found. Surgery was performed on the first day of admission, and the anterior interhemispheric approach was selected. The anomalous branch of the right ICA ran beneath the right optic nerve, ascended between the optic nerves, and supplied the ACoA system. The left hypoplastic A1 segment entered the ACoA. However, the right A1 segment could not be found. The aneurysmal neck, situated between the bilateral callosomarginal arteries and the unpaired pericallosal artery, was clipped with Sugitas curved clip. The postoperative course was uneventful and a follow-up angiograph revealed successful obliteration of the aneurysm.

Clinicopathological study of bacterial intracranial aneurysms

The authors report the clinicopathological findings in six cases of bacterial intracranial aneurysms. All patients received appropriate high-dose antibiotics, and four were treated surgically. One patient with multiple aneurysms of the main trunks died of disseminated intravascular coagulation. Autopsy disclosed no apparent aneurysm or inflammatory cell infiltration, but a partially interrupted internal elastic lamina and thickened intima were disclosed at the angiographical aneurysm sites. These findings suggest that 1) appropriate high-dose antibiotics are effective against inoperable bacterial aneurysms in the main trunks, 2) new aneurysms may be formed in patients with cyanotic congenital heart disease, because bacterial emboli can directly reach the cerebral circulation and reimplant on the fragile arterial walls after vasculitis. Histological examination of aneurysmal walls revealed inflammatory cell infiltration after resolution of clinical endocarditis. This suggests that both appropriate high-dose antibiotic therapy and surgery should be considered in patients with distal bacterial aneurysms.

[Clinicopathological studies of three cases of cerebral aneurysms associated with systemic lupus erythematosus]

We report three cases of ruptured cerebral aneurysms associated with systemic lupus erythematosus (SLE). A 52-year-old woman (case 1) with a fifteen-year history of systemic lupus erythematosus suddenly lost consciousness. She was admitted in a state of deep coma. A computed tomography (CT) scan revealed acute hydrocephalus and diffuse subarachnoid hemorrhage in the basal, interhemispheric and bilateral Sylvian cisterns. Fifteen years prior to this admission, cerebral angiograms demonstrated no cerebral aneurysm. She underwent ventricular drainage immediately. Postoperatively, her condition did not improve, and she died on the 18th day. During the autopsy, two saccular cerebral aneurysms were found: one aneurysm was at the right middle cerebral artery bifurcation, and another one was on the anterior communicating artery, which had disruption of the internal elastic lamina and medial smooth muscle, and infiltration of inflammatory cells. In the major cerebral arteries, for example the bilateral internal carotid arteries, disruption or dissection of the internal elastic lamina, intimal fibrosis and transmural infiltration of inflammatory cells were observed. The second patient, a 36-year-old woman with a six-year history of SLE, was admitted to our hospital with sudden severe headache. A CT scan showed subarachnoid hemorrhage, and cerebral angiograms disclosed saccular cerebral aneurysms on the anterior communicating artery and the left superior cerebellar artery, and a fusiform one on the left posterior cerebral artery. Surgery was not recommended because of her multiple medical problems. Her consciousness improved gradually over 2 months. She was transferred to the department of internal medicine for treatment of renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Epstein-Barr viral genomes in carcinoma metastatic to lymph nodes. Association with nasopharyngeal carcinoma

Lymphoepithelioma of the nasopharynx is a neoplasm known to have a strong association with Epstein-Barr virus (EBV). Using the Southern blot method, polymerase chain reaction (PCR), and/or in situ hybridization, we examined lymph nodes containing metastatic carcinoma, including metastatic lymphoepithelioma, for the presence of EBV genomes in order to determine whether EBV was associated exclusively with lymphoepithelioma. All of six lymph nodes from patients with lymphoepithelioma in the neck were found to have EBV genomes using the above methods. In four of the six cases, the primary site was the nasopharynx, and in the other two no primary site was found. Four of 12 squamous cell carcinomas and one of 18 adenocarcinomas expressed the EBV genome only by PCR, but not by Southern blotting or in situ hybridization, probably due to the presence of latent EBV in lymphocytes. These results indicate that metastatic carcinoma in lymph nodes showing EBV genomes revealed by Southern blotting or in situ hybridization is lymphoepithelioma, and that the nasopharynx is very likely the primary site.

Site-specific mutagenesis using a gapped duplex vector: a study of translesion synthesis past 8-oxodeoxyguanosine in E. coli

We have constructed a gapped plasmid vector in which a single defined lesion is introduced, site-specifically, within a single-strand region. Efficiency of translesional synthesis is determined by the number of colonies recovered following transformation of E. coli. The nucleotide sequence of progeny plasmids in the gapped region of the vector reflects incorporation of bases opposite and near the lesion. The analysis detects non-mutagenic as well as mutagenic events. This system was used to establish the mutagenic potential of 2'-deoxy-7,8-dihydro-8-oxoguanosine (8-oxodG), a lesion produced by the action of active oxygen species on DNA. The presence of 8-oxodG did not affect the number of transformants recovered. Most transformants (greater than 99%) contained G:C pairs at the site of the lesion; however, a limited number of targeted G----T transversions were observed in the presence and absence of SOS induction. Base substitutions neighboring the lesion, reported for an in vitro system, were not observed. We conclude that the 8-oxodG lesion in DNA is weakly mutagenic in E. coli.

Role of cysteine residues in human NADH-cytochrome b5 reductase studied by site-directed mutagenesis. Cys-273 and Cys-283 are located close to the NADH-binding site but are not catalytically essential

Human NADH-cytochrome b5 reductase (EC 1.6.2.2) contains 4 cyteine residues (Cys-203, -273, -283, and -297). Cys-283 was previously proposed to be involved in NADH binding by chemical modification (Hackett, C. S., Novoa, W. B., Ozols, J., and Strittmatter, P. (1986) J. Biol. Chem. 261, 9854-9857). In the present study the role of cysteines in the enzyme was probed by replacing these residues by Ser, Ala, or Gly employing site-directed mutagenesis and chemical modification. Four mutants, in which 1 of the 4 Cys residues was replaced by Ser, retained comparable kcat and Km values to those of the wild type. All of these mutants were as sensitive as the wild type to treatment with SH modifiers, while a double mutant, C273S/C283S was resistant. Since inhibition by SH modifiers was protected by NADH, Cys-273 and Cys-283 were implicated to be close to the NADH-binding site. C273A and C273A/C283A mutants showed approximately one-fifth of the enzyme-FAD reduction rate of the wild type as revealed by steady-state kinetics and by stopped-flow analysis. Anaerobic titration has shown that reduction and re-oxidation processes including formation of the red semiquinone of these mutants were not significantly altered from those of the wild type. From these results it was concluded that none of the Cys residues of the enzyme are essential in the catalytic reaction, but Cys-273 conserved among the enzymes homologous to NADH-cytochrome b5 reductase homologous to NADH-cytochrome b5 reductase plays role(s) in facilitating the reaction. A difference spectrum with a peak at 317 nm, which was formerly considered to be derived from the interaction between NAD+ and Cys-283 of the reduced enzyme, appeared upon binding of NAD+ not only to the reduced wild type enzyme but also to the C273A/C283A mutant in which both of the Cys residues close to the NADH-binding site were replaced.

Exonic point mutations in NADH-cytochrome B5 reductase genes of homozygotes for hereditary methemoglobinemia, types I and III: putative mechanisms of tissue-dependent enzyme deficiency

We analyzed the NADH-cytochrome b5 reductase gene of hereditary methemoglobinemia type I and type III, by using PCR-related techniques. The mutation in type I is a guanine-to-adenine substitution in codon 57 of exon 3 of the NADH-cytochrome b5 reductase gene, and the sense of this codon is changed from arginine to glutamine. In type III the mutation is a thymine-to-cytosine transition in codon 148 of exon 5, causing leucine-to-proline replacement in type III. The former mutation abolishes the MspI recognition site. Homozygosity for the former mutation in a patient with type I was confirmed by restriction analysis of PCR-amplified fragments and by dot blot hybridization of amplified products with allele-specific oligonucleotide probes. The latter mutation generates a recognition site for MspI. Amplification of exon 5 by PCR followed by digestion with MspI revealed homozygosity for this mutation in patients with type-III. Putative mechanisms of tissue-dependent enzyme defects in hereditary methemoglobinemia are discussed.

Neurography of the brachial plexus in the thoracic outlet syndrome

Neurography of the brachial plexus was carried out in 180 patients with suspected thoracic outlet syndrome and in 30 normal subjects. In the thoracic outlet syndrome, abnormalities were found in 85% of suspected cases. Narrowing was seen in the scalenus triangle (30%), in the costoclavicular-space (75%) and at the subcoracoid level (6%). Translucent lines were present in 53%, and in 28% of the controls. After successful operation, the appearances returned to normal. Neurography was helpful in making the diagnosis and in determining the correct surgical procedure.

Mycotic (Aspergillus) arteritis resulting in fatal subarachnoid hemorrhage: a case report

A seventy-one year-old Japanese man suffering from carcinoma of the common bile duct died from subarachnoid hemorrhage secondary in intracranial mycotic arteritis (MA). Repeated cultures of the discharge from the draining tubes, the tip of intravenous hyperalimentation catheters, blood, sputum, and urine failed to grow any fungus. Autopsy disclosed MA due to Aspergillus at the terminal portion of the right internal carotid artery close to the posterior communicating artery.

In situ immunophenotype of macrophages and lymphocytes in granuloma formation of tuberculous lymphadenitis in HIV-infected and immunocompetent patients

The phenotype of inflammatory cells in lymph nodes from 16 patients with culture-proven tuberculous lymphadenitis were examined by histological and immunohistochemical techniques. Eight patients were suffering from a symptomatic HIV1 infection and 8 patients were immunocompetent individuals without positive HIV1 serology. In addition, the lymph nodes of 2 AIDS patients with Mycobacterium avium-intracellulare infection were examined using the same techniques. Characteristic granulomas with or without caseation were observed in the 8 immunocompetent and the 4 HIV1-infected patients with less marked lymphopenia of CD4+ peripheral blood lymphocytes (PBL). In lymph nodes from the other HIV1-infected patients with more severe depression of CD4+ PBL, no epithelioid cell formation was present; instead, foamy macrophages were found. The phenotype of the macrophages underwent progressive changes in parallel with the decreasing numbers of CD4+ PBL. Foamy macrophages in M. avium-intracellulare infection exhibited remarkable erythrophagocytotic activity and may represent an end-stage phenotype. They were positive for S100 protein and did not produce lysozyme or alpha-1-antichymotrypsin. They lost the antigen which was detected by monoclonal antibody Mac387 whereas positivity for HLA-DR, CD68 and KI-M8 was preserved. While many lymphocytes expressed CD25 (IL2 receptor) in cases with typical granulomas, there was no such CD25 expression in cases without epithelioid cell formation. Although granulomas have been produced in experimental animals independently of cell-mediated immune mechanisms, our results suggest that T-cell functions are necessary for epithelioid granuloma formation in human tuberculosis.

Structural role of serine 127 in the NADH-binding site of human NADH-cytochrome b5 reductase

Serine 127 of human NADH-cytochrome b5 reductase was replaced by proline and alanine by site-directed mutagenesis. The former mutation has been found in the genes of patients with hereditary deficiency of the enzyme. Both the mutant enzymes (Ser-127----Pro mutant and Ser-127----Ala mutant) were overproduced in Escherichia coli and purified to homogeneity. The two purified mutant enzymes showed indistinguishable spectral properties which differed from those of the wild-type enzyme. The mutant enzymes showed higher molecular extinction coefficients at 462 nm than that of the wild-type enzyme. Quenching of FAD fluorescence in these mutant enzymes was significantly less than that in the wild-type enzyme. Furthermore, circular dichroism spectra of the mutant enzymes were different, in both the visible and ultraviolet regions, from that of the wild-type enzyme. The spectra of the mutant enzymes in the visible region were restored to almost the same spectrum as the wild type upon reduction with NADH. Ser-127----Pro mutant and Ser-127----Ala mutant showed very low Kcat/Km (NADH) values (5 x 10(7) and 3.5 x 10(7) s-1 M-1, respectively) with cytochrome b5 as an electron acceptor, than that of the wild-type enzyme (Kcat/Km (NADH) = 179 x 10(7) s-1 M-1), while the Kcat/Km (cytochrome b5) value for each enzyme was similar. The mutant enzymes were less thermostable than the wild-type enzyme. These results indicate that serine 127 plays an important role to maintain the structure of the NADH-binding site in the enzyme.