Characterization of ionomycin as a calcium ionophore

The ionophorous properties of a new antibiotic, ionomycin, have been studied. It was found that the antibiotic is capable of extracting calcium ion from the bulk of an aqueous phase into an organic phase. The antibiotic also acts as a mobile ion carrier to transport the cation across a solvent barrier. The divalent cation selectivity order for ionomycin as determined by ion competition experiments was found to be: Ca greater than Mg greater than Sr = Ba, where the binding of strontium and barium by the antibiotic is insignificant. The antibiotic also binds La3+ to some extent, but its complexation with monovalent alkali metal ions is negligible. Measurement of the binding of ionomycin with Ca2+ indicates that ionomycin complexes and transports calcium ion in a one to one stoichiometry.

Pharmacological evaluation of cefaclor in volunteers

The plasma and urine concentrations of cefaclor were measured after oral administration of single and multiple doses to volunteers. Cefaclor was rapidly absorbed, rapidly excreted in the urine, well tolerated without toxicity, and failed to accumulate in the plasma with chronic dosing.

Radionuclide imaging in herpes simplex encephalitis

Eight patients with herpes simplex encephalitis among the 10 cases diagnosed at the University of Kansas Medical Center from 1966 to 1976 were studied with 99mTc early in their diagnostic work-up. The images were unilaterally positive in the temporal lobe area in all 8 patients. Radionuclide studies can suggest herpes simplex as the specific etiology in cases of encephalitis and can also indicate the best site for brain biopsy to confirm the diagnosis by fluorescent antibody techniques. Appropriate antiviral therapy should be instituted as soon as possible to alter the course of this destructive form of viral encephalitis.

A prospective study of tracheobronchial bacterial flora in acutely brain-injured patients with and without antibiotic prophylaxis

The authors observed prospectively 28 brain-injured patients, who required respiratory tract intubation, to determine the effect of antibiotic prophylaxis on bacterial flora, the rate of flora change, and the appearance of infection. Antibiotics not only failed to alter the rate of abnormal colonization but were associated with an earlier appearance of Gram-negative bacilli, the organisms that produced the most severe infections. Although more infections occurred in patients initially untreated with antibiotics, these infections were usually mild and caused by organisms susceptible to highly effective and relatively safe drugs. Although highly reproducible as a laboratory determination, the nitroblue tetrazolium dye test score showed no consistent relationship with the presence or absence of bacterial infection. Regular and extensive clinical and laboratory observations, including cultures of the respiratory tract helped to make the antibiotic administration in these patients specific, appropriate, and reasonable. Broad spectrum antibiotic prophylaxis does not prevent and may enhance the development of severe pulmonary infection in these patients.

Two modes of metabolic regulation of lysyl-transfer ribonucleic acid synthetase in Escherichia coli K-12

Lysyl-transfer ribonucleic acid (tRNA) synthetase activity was compared in three independently isolated Escherichia coli K-12 mutants of the enzyme S-adenosyl-L-methionine synthetase (metK mutants) and their isogenic parents. In all three cases the activity of the lysyl-tRNA synthetase was elevated two- to fourfold in the mutant strains. Glycyl-L-leucine (3 mM) usually enhanced lysyl-tRNA synthetase activity two- to threefold in wild-type cells but did not further stimulate the synthetase activity in metK mutants. By two other criteria, the lysyl-tRNA synthetase from wild-type cells grown with the peptide and from the metK mutant RG62, grown in minimal medium, were similar. These criteria are enhanced resistance to thermal inactivation and altered susceptibility to endogenous proteases when compared with the synthetase from wild-type cells grown in minimal medium. In a separate set of experiments, the activities of the lysyl-, arginyl-, seryl-, and valyl-tRNA synthetases were measured in an isogenic pair of relt and rel strains of E. coli grown in a relatively poor growth medium (acetate) and in enriched medium. In the rel+ strain the level of all four synthetases was higher (two- to fourfold) in the enriched medium as expected. In the rel strain the difference in the activities of the synthetases between the two media were diminished. In all four cases the activities of the synthetases were higher in acetate medium in the rel strain. Evidence is presented that these two modes of metabolic regulation act independently.

Hyposplenism and disseminated intravascular coagulation (DIC) in fulminant pneumococcal sepsis

A case of pneumococcal sepsis with DIC is reported. The patient had hyposplenism from thorium dioxide administration 23 years previously. Evidences of consumptive coagulopathy were verified by clinical manifestations of shock, generalized petechiae, abnormal hemostatic studies, and autopsy findings. The possible pathogenetic mechanism(s) of DIC in hyposplenism and pneumococcemia are reviewed.

Endocarditis treated with clindamycin: relapse and liver dysfunction

Clindamycin was used to treat six patients with endocarditis because of allergy to penicillin in five, and an unfavorable clinical response to methicillin in one. Only one patient had an uneventful cure with clindamycin. Two had hepatotoxicity which resolved rapidly after clindamycin was stopped. Two patients, one of whom had an aortic prosthesis, had completed four to six weeks of clindamycin therapy when clinical relapse occurred and blood cultures were again positive for a clindamycin-sensitive isolate. A fifth patient had peptostreptococcal endocarditis. Despite a favorable initial clinical and bacteriologic response, blood cultures taken on the 20th day of therapy again grew the Peptostreptococcus. This relapse pathogen had become resistant to clindamycin and was 100-fold less sensitive than the initial isolate. The few conditions in which clindamycin is indicated for therapy of bacterial endocarditis are outlined.

Characteristic early electroencephalographic changes in herpes simplex encephalitis

We review electroencephalograms taken from 17 patients with severe meningoencephalitis within seven days of onset of CNS symptoms and prior to cortical brain biopsies. All patients had CNS disease clinically compatible with the diagnosis of herpes simplex encephalitis (HSE). The diagnosis was demonstrated by the isolation of virus from the brain in five patients (group 1) but considered highly unlikely in the other 12 patients (group 2) by negative immunofluorescent studies and failure of viral isolation from the brain tissue. Abnormal but nonspecific EEGs with diffuse or focal slowing were found in all patients. Distinctive high-voltage, 1-cycle-per-2-to-3 seconds periodic sharp waves from unilateral temporal lobes were seen only in three of the five patients with virologically proved HSE but in none of the 12 patients without viral isolation. This EEG pattern is strikingly similar in all three patients, regardless of their age, and may be specific for the early diagnosis of HSE prior to brain biopsy. The EEGs of the other two patients with proved HSE did not contain such abnormalities. Athough periodic EEGs with some resemblance to those previously described may occur in other CNS disorders, their presence strongly suggests the diagnosis of HSE when recorded from patients with viral meningoencephalitis. Moreover, EEGs may help locate the best site for cerebral biopsy since maximal yield of the virus in this study was from unilateral temperoal lobes corresponding with the site of local EEG changes.

Feedback inhibition of the synthesis of an antibiotic: aurodox (X-5108)

The effect of aurodox on its own biosynthesis by Streptomyces goldiniensis was studied. It was found that addition of exogenous aurodox inhibits further accumulation of aurodox by the antibiotic-producing culture. Both long term fermentation studies with aurodox-14C and precursor incorporation studies over short time periods indicated that aurodox synthesis was regulated by feedback inhibition. The concentration of aurodox required to completely block further synthesis of the antibiotic was about 400 microng/ml. This is the same as the maximum concentration of aurodox normally accumulated by the culture used in this study. Antibiotic synthesis was inhibited not only by aurodox but also by some structural analogs of aurodox including several having no antibacterial activity. This effect was immediate and readily reversible, indicating that it could be due to inhibition of an enzyme(s) involved in the biosynthesis of aurodox.

Möbius syndrome due to brain stem tegmental necrosis

Möbius syndrome undoubtedly results from a variety of disorders affecting central or peripheral portions of appropriate cranial nerves or their target muscles. Pathological alterations observed in cranial nuclei are most often viewed as aplastic or dysplastic lesions. Two patients with Möbius syndrome with associated facial and skeletal malformations showed mineralized necrotic foci in multiple brain stem nuclei. Prenatal encephalomalacic lesions represent the pathological basis for some cases of congenital static Möbius syndrome.

Measurement of antibodies to Herpesvirus hominis by indirect immunofluorescent antibody method

Antibodies to Herpesvirus hominis (HVH) were evaluated by indirect immunofluorescent antibody (FA) method. Frozen sections of HVH infected mouse brain provided antigens for FA staining. Our data indicate that indirect FA staining is a rapid, sensitive, and reproducible method for measurement of antibodies to HVH. Indirect FA method can be applied as an additional tool for the measurement of antibodies to HVH and can be applied for epidemiological survey of HVH infections.

Recurrent conjugal neuralgia caused by Herpesvirus hominis type 2

Leg neuralgia is usually caused by nerve root irritation, and is seldom considered of viral origin. Two married couples had recurrent leg pain in a dermatome distribution. In each episode, after one to three days of neuralgia, herpetic vesicles appear on or near the genitalia. Herpesvirus hominis (HVH) was isolated from vesicles or cervix in three patients and was serologically identified as herpesvirus honinis type 2. Prolonged follow-up has not shown progression of the syndrome or any permanent neurologic damage. Treatment with topical neutral red and photoinactivation has not only reduced local lesion healing time and frequency of attacks, but it has also given prompt relief of neuralgia.

Nephropathy caused by methicillin therapy for staphylococcal septicemia

Nephropathy, eosinophilia and fever were observed in an 18-year-old man being treated for staphylococcal septicemia. Parenteral challenge with suspected sensitizing agents confirmed methicillin as the likely offender. Review of the literature relating to methicillin-induced nephropathy suggests a hypersensitivity origin for this disorder, but immunologic and ultrastructural investigation to date has failed to elucidate pathogenesis.

Use of clindamycin in patients with liver disease

Hepatotoxicity has been noted by several investigators during parenteral use of clindamycin, and some have reported that drug half-life is prolonged in the presence of liver disease. We administered 300 mg of clindamycin intravenously at 12-h intervals for 2 days to patients with acute and chronic hepatitis, cirrhosis, and controls to determine whether clindamycin will exacerbate preexisting hepatic dysfunction or whether drug excretion will be delayed in patients with liver disease as compared with controls. Exacerbation of hepatotoxicity was not found in this study. There was a small, but significant, delay in drug elimination between cirrhotics and controls, even after the first dose of clindamycin (P < 0.05); however, half-lives in all categories were in the range usually considered normal. We conclude that clindamycin can be used in liver disease in some circumstances, if proper precautions are exercised.

Suppressor T cells and host resistance to tye 111 pneumococcus after treatment with antilymphocyte serum

The antibody response to type III pneumococcal polysaccharide (SS-II) was significantly increased in mice treated with antilymphocyte serum (ALS). BALG/c mice given 0.25 ml of ALS on days -1, 0, and 1 relative to the days of immunization with 0.5 mug of SSS-II had a 20-fold increment (11,383 increased to 199,917) in the number of splenic plaque-forming cells enumerated on day 5 compared with untreated, immunized controls. This effect has been attributed to the elimination of subpopulation of thymus-derived lymphocytes (T cells) that has suppressor function. The present series of experiments relate the augmented antibody response to SSS-II in mice treated with ALS to increased host resistance after infection with Streptococcus pneumoniae, type III (Pn-II). The 50% lethal dose of Pn-III in niminnunized mice was 102 and the 100% lethal dose was 103 organisms. Mice immunized with 0.5 mug of SSS-III and challenged 5 days later with Pn-III were completely protected against a dose of up to 108 organisms. Mice treated with 0.25 ml of ALS on days -1, 0, and 1, immunized with SSS-III on day 0, and challenged with 2.5 X 10(9) Pn-III on day 5 had a mean survival time of greater than 100 h compared with 16 h for immunized non-serum-treated controls. Animals given a single injection of ALS before immunization showed no increase in resistance, whereas mice treated after immunization had significant prolongation of survival times. Untreated, immunized mice challenged with 5 X 10(9), 1 X 5 X 10(8) Pn-II survived 14 to 19 h, whereas ALS-treated animals had mean survival times of 48, 174, and 222 h, respectively. These findings suggest that immunoregulatory T cells may have a biologically significant effect in a narrow zone in which the normal host immune response is insufficient but still potentially capable of providing some additional degree of protection if suppressor cells are elimated.

Rapid diagnosis of primary influenza pneumonia

Primary influenza pneumonia is a disease of high mortality. Differentiation between a bacterial and viral etiology for the pulmonary infiltrates frequently presents a diagnostic dilemma. Rapid diagnosis is essential; and once established, the patient requires careful supportive therapy. This report describes two patients with primary influenza pneumonia complicated by severe respiratory failure. Early diagnosis of the pulmonary infiltrates was accomplished by obtaining bronchial secretions with fiberoptic bronchoscopy and staining them with influenza-A fluorescent conjugate. One patient died of the complications of this illness, despite maximal supportive therapy. The other patient survived the illness and at the time of hospital discharge was showing marked improvement in his exercise tolerance. There was subsequent gradual return of ventilation and gas transport function to normal values.

Immunofluorescent staining for the measurement of antibodies to Herpesvirus hominis

Frozen sections of Herpesvirus hominis-inoculated mouse brain provide excellent antigens for indirect immunofluorescent staining of antibodies to H. hominis in serum. Indirect immunofluorescent staining is a rapid, sensitive, and reproducible method for the measurement of antibodies to H. hominis. The method can be applied to the clinical and epidemiological studies of H. hominis infections.

Bacterial flora and infection in patients with brain injury

✓ Twenty-five patients with acute head trauma were studied prospectively for appearance of infection during hospitalization in an acute care unit. The study demonstrates: multiple changes in bacterial flora particularly in the respiratory tract, a significant morbidity due to bacterial changes in the respiratory tree, a negligible incidence of bacterial disease due to physiological monitoring procedures, and an inability to correlate changing flora with specific therapeutic or manipulative procedures except tracheostomy. Mortality correlates well with the severity of illness and indirectly with changes in bacterial flora. Despite the frequent isolation of coagulase-positive staphylococci, severity of infectious complications correlate most closely with the acquisition of gram-negative organisms in the respiratory tract.

Immunofluorescent studies of human cell cultures and chick embryos inoculated with the ameboid cell-"lipovirus" complex

Tissue culture cells of human origin (HeLa, Lich, and AV(3)) were inoculated with the AL complex. By immunofluorescent staining, AL complex antigen was detectable in the cytoplasm of infected cells as punctate fluorescent granules during the early stage and as homogeneous fluorescence during the late stage of infection. By combining fluorescence and phase-contrast microscopy, many infected cells with cytoplasmic AL complex antigen were shown to have a normal nuclear morphology indistinguishable from uninfected cells. Initiation of AL complex infection was interpreted as occurring by transfer of transmissible factor(s) from cell to cell by contact and mutiplication of such factor(s) therein. Chick embryos were susceptible to AL complex infection following allantoic or amniotic inoculations. Antigen and infectious AL complex were demonstrable in the liver, brain, intestines, lungs, and embryonic membranes. Further investigations on AL complex and its relation to human disease are suggested.