Endoscopic vacuum therapy in salvage and standalone treatment of gastric leaks after bariatric surgery

Introduction

Gastric leaks constitute some of the most severe complications after obesity surgery. Resulting peritonitis can lead to inflammatory changes of the stomach wall and might necessitate drainage. The inflammatory changes make gastric leak treatment difficult. A common endoscopic approach of using stents causes the problem of inadequate leak sealing and the need for an external drainage. Based on promising results using endoscopic vacuum therapy (EVT) for esophageal leaks, we implemented this concept for gastric leak treatment after bariatric surgery (Ahrens et al., Endoscopy 42(9):693–698, 2010; Schniewind et al., Surg Endosc 27(10):3883–3890, 2013).

Methods

We retrospectively analyzed data of 31 gastric leaks after bariatric surgery. For leak therapy management, we used revisional laparoscopy with suturing and drainage. EVT was added for persistent leaks in sixteen cases and was used in four cases as standalone therapy.

Results

Twenty-one gastric leaks occurred in 521 sleeve gastrectomies (leakage rate 4.0%), 9 in 441 Roux-en-Y gastric bypasses (leakage rate 2.3%), and 1 in 12 mini-bypasses. Eleven of these gastric leaks were detected within 2 days after bariatric surgery and successfully treated by revision surgery. Sixteen gastric leaks, re-operated later than 2 days, remained after revision surgery, and EVT was added. Without revision surgery, we performed EVT as standalone therapy in 4 patients with late gastric leaks. The EVT healing rate was 90% (18 of 20). In 2 patients with a late gastric leak in sleeve gastrectomy, neither revisional surgery, EVT, nor stent therapy was successful. EVT patients showed no complications related to EVT during follow-up.

Conclusion

EVT is highly beneficial in cases of gastric leaks in obesity surgery where local peritonitis is present. Revisional surgery was unsuccessful later than 2 days after primary surgery (16 of 16 cases). EVT shows a similar healing rate to stent therapy (80–100%) but a shorter duration of treatment. The advantages of EVT are endoscopic access, internal drainage, rapid granulation, and direct therapy control. In compartmentalized gastric leaks, EVT was successful as a standalone therapy without external drainage.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00423-021-02365-9.

Screening for maternal coeliac disease as a potential risk factor for orofacial clefts--a pilot study

There is increasing evidence that dietary folic acid deficiency in utero may increase the risk of developing the 'cleft lip with or without cleft palate' (CL±P) variant of orofacial cleft. Coeliac disease is a common cause of folic acid malabsorption, and in the majority of cases remains undiagnosed. This pilot study assessed the seroprevalence of undiagnosed coeliac disease in a cohort of mothers of infants with CL±P in the Hyderabad area of India. The seroprevalence of coeliac disease of 1.15% (95% confidence interval 0.37-2.66%) was little different from the expected figure based on published population studies, making a clinically significant association unlikely.

[Pulmonary nocardiosis with trimethoprime/sulphamethoxazole-resistant Nocardia paucivorans in a patient with no signs of immunosuppression]

This is so far the first published case report of a Nocardia paucivorans infection in an immunocompetent patient. A 54-year-old farmer was hospitalised with a history of coughing and fever for a period of five months. There was no indicator of either primary of secondary immunodeficiency in the prior medical history. A chest X-ray showed pneumonic infiltrates in the right middle und lower lobes, which progressed despite of antibiotic therapy with macrolides. A transbronchial biopsy revealed unspecific granulomatous inflammation of soft tissues. N. paucivorans - grew in cultures of sputum, bronchoalveolar lavage, and transbronchial biopsy. Oral antibiotic therapy was started with trimethoprime-sulphamethoxazole (TMP/SMX) and amoxicillin plus clavulanic acid. Susceptibility testing revealed high level resistance to TMP/SMX, which was consequently replaced by ciprofloxacin. Six months later, infiltrates had completely resolved and the patient did not report any residual clinical symptoms. The present case showed once again that nocardiosis is not limited to patients with immunodeficiencies. However, conservative combination therapy with oral antibiotics seems to be sufficiently effective for nocardiosis in the immunocompetent patient. For cases of suspected nocardiosis, a step-wise, risk-based diagnostic and therapeutic procedure is proposed.

[The ovarian hyperstimulation syndrome -- a rare differential diagnosis of a unilateral pleural effusion]

This case presentation describes a 29 year-old female who developed a severe ovarian hyperstimulation syndrome (OHSS) with ascites and a right-sided pleural effusion following in-vitro-fertilisation. A total of 4,2 l of pleural fluid was removed during 3 thoracocenteses. The symptoms as well as the fluid production ceased after 2 weeks. The OHSS is altogether a rare, but potentially life-threatening complication of in-vitro-fertilisation. Due to the well-characterized clinical setting in which the syndrome appears, there are only few differential diagnoses to consider. OHSS is likely to originate from altered capillary permeability, but its pathogenesis is not yet fully understood. Clinical symptoms usually resolve within 2 weeks of supportive therapy. In case of persistency, however, especially pulmonary embolism and infectious causes of pleural fluid production have to be excluded.

The use of commercial saponin from Quillaja saponaria bark as a natural larvicidal agent against Aedes aegypti and Culex pipiens

The larvicidal activity of commercial bark saponin extract (Sigma) from Quillaja saponaria was studied on 3rd-4th instar larvae of Aedes aegypti and Culex pipiens (vectors for dengue fever and Western Nile virus, respectively). The larvae were exposed to serial concentrations (1000, 800, 500, 300, 100, 10, 1, 0.1 and 0.01 mg/l) of the extract for 1, 3, 5, 7 and 11 days. The results indicate that commercial bark saponin is toxic, causing 100% larval mortality in A. aegypti and C. pipiens after 1 and 5 days at a dosage of 800 and 1000 mg/l, respectively. Interestingly, while bark saponins had a toxic effect on larvae there was no effect on egg hatchability in either species. The results obtained suggest that, in addition to their known activities, saponins can also serve as natural larvicidal compounds.

Inhalation of aerosolized vitamin a: reversibility of metaplasia and dysplasia of human respiratory epithelia -- a prospective pilot study

The objective of this preliminary uncontrolled study was twofold: First, to assess the feasibility of retinyl palmitate inhalation and second, to analyze the changes of metaplastic lesions of the respiratory epithelium (metaplasia or dysplasia) following retinyl palmitate inhalation. The response to a daily dose of 18.000 I.U. retinyl palmitate by inhalation over a period of 3 month was assessed in 11 subjects (9 smokers, 2 ex-smokers). Using white-light bronchoscopy combined with autofluorescence bronchoscopy, bronchial biopsies were taken before and after a 3 month-period. The biopsy samples were evaluated blind by a referee lung pathologist. The overall response rate (remission or partial remission) was 56% (95% CI 0.30 0.79; p<0.05). These data suggest that inhalation of retinyl esters could be a promising therapeutical approach for chemoprevention of lung cancer. Vitamin A; chemoprevention; lung cancer; squamous metaplasia; dysplasia; retinoids

Lymphocytes in the bronchoalveolar space reenter the lung tissue by means of the alveolar epithelium, migrate to regional lymph nodes, and subsequently rejoin the systemic immune system

Lymphocytes in the bronchoalveolar space are routinely obtained and examined in lung diseases such as asthma or sarcoidosis. In a pig model, labeled lymphocytes were found in regional lymph nodes after intrabronchial instillation, indicating that reentry of lymphocytes from the bronchoalveolar space into the body is possible. In the present study, the route and kinetics of the reentry of bronchoalveolar lymphocytes were investigated in a congenic rat model using immunohistochemistry on cryostat and semithin sections and confocal laser scanning microscopy. As early as 15 min after intratracheal instillation lymphocytes were found to leave the bronchoalveolar space by transmigration through alveolar but not bronchial epithelium and were observed in interstitial alveolar tissue. At 6 hr after intratracheal instillation, T and B lymphocytes appeared in the draining lymph nodes of the lung with an increase after 24 and 48 hr. The kinetic pattern clearly differed in nondraining lymph nodes and other organs. After 6 hr, only single cells were found in nondraining lymph nodes, spleen, and blood with a slight increase after 24 hr, and only occasionally were single cells seen in the liver, thymus, or Peyer's patches 24 and 48 hr after instillation. In conclusion, T and B lymphocytes can leave the alveolar space by reentry into the lung tissue through alveolar epithelium. They reach regional lymph nodes by means of lymphatic vessels and are then distributed all over the body to rejoin the systemic immune system. Coming into contact with environmental antigens, these lymphocytes could perform an important function in the lung immune system and might be a target for inhalative therapy.

Memnopeptide A, a novel terpene peptide from Memnoniella with an activating effect on SERCA2

The terpene peptide memnopeptide A (1), C76H108N16O18S, MW 1564, was isolated from a culture of the fungus Memnoniella echinata FH 2272 on casein peptone. The structure of the novel compound was elucidated with the aid of 2D NMR experiments and from amino acid analysis and mass spectrometric sequencing of the peptide. The compound consists of a known phenylspirodrimane subunit linked to the decapeptide Met-His-Gln-Pro-His-Gln-Pro-Leu-Pro-Pro. This proline-rich peptide is a subsequence of beta-casein. From the observed absence in the literature of any other highly significant sequence homologues, memnopeptide A can be assumed to arise from metabolic products of the fungus with direct incorporation of constituents of the nutrient medium. The formation of memnopeptide A suggests this may be a mechanism for storage of amines by the fungus. Memnopeptide A has weak antibacterial activity against gram-positive bacteria and effects half-maximal activation of sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA2) at a concentration of 12.5 microM.

State benefit design choices under SCHIP - implications for pediatric health care

This policy brief is the second in a series of reports focusing on the design of state SCHIP programs as they near full implementation. It examines the extent to which state agencies adopt conventional insurance norms or adhere to special principles of Medicaid coverage design for children in designing separately administered (or freestanding) SCHIP programs. The issue of coverage design is particularly relevant for children with low uses standardized coverage norms to limit coverage and treatment. These standardized norms take the form of across-the-board treatments and exclusions, limited definitions of medical necessity, and the use of irrebuttable, standardized treatment guidelines in determining when covered treatments will be available. All of these practices are impermissible under Medicaid, which uses exceptionally broad preventive standards to determine coverage of children; such standards favor coverage of children with low prevalence problems.

U.S. civil rights policy and access to health care by minority Americans: implications for a changing health care system

The history of health care discrimination as well as ongoing, extensive evidence of racial disparities argue for continued vigilance in the area of health care and civil rights. Under Title VI of the Civil Rights Act of 1964, individuals have challenged de facto discriminatory policies adopted by health entities receiving federal financial assistance. Title VI health litigation is difficult because of complex issues of proof as well as confounding problems of poverty and lack of health insurance that affect both claims and remedies. An analysis of cases brought under the law suggests that discrimination claims within a particular market fare better than those challenging decisions to relocate or alter the market served. This has important implications for claims involving discrimination by managed care organizations. Because the same potential for discrimination exists in the new health system of managed care, although in altered form, data collection and evaluation are warranted.

[Bronchoscopy in Germany. Cross-sectional inquiry with 681 institutions]

Bronchoscopy represents an integral part of the diagnostic tools in pulmonary medicine. Recently, it has also gained considerable attention for its therapeutic properties. To elucidate equipment, indications and procedural techniques of bronchoscopy units, a retrospective survey of 1232 hospitals and practices is conducted. 687 questionnaires are received back (response rate 56%). 681 of which are statistically evaluated. Two thirds of the physicians in charge are internists, one third are pulmonary care specialists. A total of 200,596 endoscopic procedures is included. The majority of procedures is done with an average of 3 bronchoscopists and in over 57% (388) of cases with an average number of 100 or less procedures per year. The five main indications are tumor, hemoptysis, infection or pneumonia, drainage of secretions and suspected interstitial disease. Overall complication rate amounts to 2.7% with an incidence of 4.6% minor and 0.7% major complications and a bronchoscopy-related mortality of 0.02%. The patterns seen in premedication, intra- and post-procedural monitoring, disinfection practices as well as documentation are quite heterogeneous. It is suggested to establish revised and updated standards for bronchoscopy, which should take the data collected into particular account. Those standards should provide the basis for a high level bronchological care throughout Germany.

Ala(0)-actagardine, a new lantibiotic from cultures of Actinoplanes liguriae ATCC 31048

The actagardine-producing strain Actinoplanes liguriae ATCC 31048, forms an additional lantibiotic when it is cultured on mannitol and soya meal. The new compound, Ala(0)-actagardine (1), has been isolated by solid-phase extraction followed by a two-step chromatographic separation. The molecular formula of 1 is C84H129N21O25S4. Its chemical structure was determined by 2D-NMR analysis and was further confirmed by an amino acid analysis, Edman degradation, and partial synthesis from actagardine. 1 exhibits a slightly higher biological activity than the parent compound actagardine. The synthetic analogs Lys(0)-actagardine (2) and Ile(0)-actagardine (3) demonstrate also antibacterial activities and emphasize the importance of the N-terminus for further derivatization.

Feglymycin, a novel inhibitor of the replication of the human immunodeficiency virus. Fermentation, isolation and structure elucidation

The novel peptide feglymycin has been isolated from cultures of Streptomyces sp. DSM 11171 by solid phase extraction, size exclusion chromatography and repeated reversed-phase chromatography. The molecular weight was found to be 1900.90 g/mol and the molecular formula is C95H97Nl3O30. Feglymycin contains 13 amino acids of which four are 3-hydroxyphenylglycine and five are 3,5-dihydroxyphenylglycine residues. The structure of the linear peptide has been determined by 1H and 13C NMR spectroscopy. The sequence was confirmed by the observed mass spectroscopic fragmentation pattern. As well as having weak antibacterial activity, feglymycin inhibits the replication of the human immunodeficiency virus (HIV) in vitro.

[1H-MR spectroscopy in anorexia nervosa: the characteristic differences between patients and healthy subjects]

PURPOSE

The neurophysiological and neuromorphological changes in patients with anorexia nervosa (AN) are well-known but the reason of both is still unknown. We have evaluated the usefulness of hydrogen (H1) magnetic resonance spectroscopy in anorexia nervosa.

METHOD

We investigated 15 patients with clinically diagnosed AN (ICD F50.0) and 17 controls without eating disorders. The body mass index (BMI) was 15.8 and 21, respectively. The spectroscopy was recorded on two voxels in the parieto-occipital white matter or in the thalamus with a water-suppressed STEAM-sequence. The metabolites were recorded with respect to phosphocreatine (PCr).

RESULTS

The ratio of NAA/PCr in both voxels were not significantly different when comparing patients vs. controls. Patients showed significantly higher ratios of choline-containing components (Cho) or, respectively Cho/PCr and NAA/PCr in the white matter. Distinct, but not significant differences were detected both for m-Ino and m-Ino/PCr in the parieto-occipital region and for the Cho- and m-Ino contained ratios in the thalamus.

CONCLUSION

AN is not associated with neuronal damage. The ratio of Cho/PCr and NAA/Cho may reflect the disturbance of membrane-turnover. It is possible that the increase of membrane catabolism leads to a hyperosmolar state. The change of m-Ino/PCr ratio may reflect the regulation of osmolarity.

Mulundocandin, an echinocandin-like lipopeptide antifungal agent: biological activities in vitro

Mulundocandin (MCN) is an antifungal lipopeptide which belongs to the echinocandin class of antimycotic agents. MCN exhibited good in vitro activity against Candida albicans and C. glabrata isolates with MIC ranges of 0.5-4.0 microg/ml and 2.0-4.0 microg/ml, respectively. MCN also exhibited some activity against C. tropicalis isolates (MIC range 1.0-8.0 microg/ml). However, MCN was poorly active against other non-albicans isolates and was inactive against Cryptococcus neoformans, Aspergillus species and Trichophyton. MCN appeared to exert its antifungal activity through preferential inhibition of germ tube formation (MIC-HY 0.015-0.03 microg/ml) and was typically less active on the yeast form (MIC 0.5-4.0 microg/ml). In kill-curve experiments 99.9% reductions in cell viability were observed following 8 hours exposure to MCN at 4 x MIC and 8 x MIC and after 5 hours exposure to 16 x MIC.

[Early diagnosis of bronchial carcinoma. Technical endoscopic progress--a step toward new screening concepts?]

Lung cancer is the most common neoplasm of our days. Its mortality has remained invariably high over the last decades and the search for effective preventive and therapeutic strategies is as imperative as ever. Carcinogenesis is a process requiring years until invasive malignancy has developed and hence offers a sufficient period for early detection of (pre-)malignant lesions. Now, tools seem available to achieve this goal: technical refinements advocate a reappraisal of screening methods for lung cancer. Also, apart from conventional diagnostic procedures, which are reviewed in this article, photodynamic and autofluorescence bronchoscopy deserve particular attention. Recent data, showing sensitivity for detection of premalignant lesions increased by factor 1.9 to 2.7 as compared to white light bronchoscopy, suggest markedly improved diagnostic options. With these new instruments, especially when combined with screening programs of high-risk groups, earliest possible diagnosis and successful therapeutic intervention seem a promising concept of reduction of lung cancer mortality.

The children's hour: the State Children's Health Insurance Program

The State Children's Health Insurance Program (CHIP) is the product of a series of policy and political compromises and generates numerous structural and policy issues for states. CHIP entitles states to federal financial aid to provide health assistance to targeted children, through Medicaid expansions, new program implementation, or a product of the two. States that elect to operate CHIP programs apart from Medicaid have enormous discretion under the law to determine how they will structure their programs, the services they will cover, the form that benefits will take, and the conditions of participation and consumer protections that will apply. Determining what approach to take, as well as how to respond to the choices posed by the statute, represents a major test of how states address the needs of children and families.

NGF-mediated survival depends on p21ras in chick sympathetic neurons from the superior cervical but not from lumbosacral ganglia

In rat embryonic sympathetic neurons from the superior cervical ganglia (SCG) NGF-mediated survival depends on the activation of the trkA receptor tyrosine kinase and on the activity of the intracellular plasmamembrane-anchored small G-protein p21ras. In contrast, chick sympathetic neurons derived from the more caudally located lumbosacral chain ganglia (LSCG) do not respond to activated p21ras (G12V-Ha-ras mutant). In these neurons endogenous p21ras and its downstream effector MAP kinase are activated but are not essential for NGF-dependent survival. Here we show that also in chick sympathetic neurons of the SCG permanently activated p21ras protein does promote neuron survival. Consistently, their NGF-mediated survival is sensitive to Fab fragments blocking endogenous p21ras activity. These results suggest that sympathetic neurons derived from sympathoenteric (SCG) and sympathoadrenal (LSCG) lineages differ in their requirement for p21ras in the NGF-mediated survival pathways.

The Politano-Leadbetter antireflux plasty. Investigation of complications in 245 children

From 1981 to 1988 245 children aged 2 months to 15 years underwent ureteral reimplantation in 326 renal units in our department. The VUR was primary in 180 patients (253 ureters) and 65 patients (73 ureters) showed associated pathologies. The follow-up program, including physical examination, urine sampling and isotope studies (including NMCU), was from 4 to 11 years after surgery. Intraoperative and early surgical complications were found in 29 cases, but no complications affected the late results, especially kidney function. Late complications have been observed in 15 cases, while in 10 cases reoperation because of persistent reflux (n = 4) obstruction (n = 3) and loss of kidney function (nephrectomy n = 3) was required. In 4 cases bladder stones required ESWL, and one patient developed hypertension.

Ras p21 protein promotes survival and differentiation of human embryonic neural crest-derived cells

We have previously shown that the oncogene product p21 Ras is essential for the survival and neurite outgrowth-promoting activity of nerve growth factor on cultured chick embryonic sensory, but not sympathetic neurons. In order to extend our observations to the human system and to non-neuronal cells, we introduced the oncogenic form of p21 Ras into the cytoplasm of three different types of cultured human embryonic neural crest derivatives (8th-11th gestational week): dorsal root ganglion neurons, sympathetic neurons, and adrenal chromaffin cells. These cells are dependent on nerve growth factor for survival and/or fibre outgrowth in vitro. In dorsal root ganglion neurons, p21 Ras promoted survival and fibre outgrowth which was quantitatively and qualitatively comparable to the nerve growth factor effect (84% vs. 95%, control 18%). Sympathetic neurons showed a similar effect, albeit with a higher background survival (91% vs. 93%, control 58%). On chromaffin cells, which respond to nerve growth factor with pronounced fibre outgrowth in culture, the effect of p21 Ras was again comparable to that of nerve growth factor (35% vs. 30%, control 5%). The survival and fibre outgrowth-promoting effects of p21 Ras on human embryonic dorsal root ganglion neurons, sympathetic neurons and chromaffin cells suggest an involvement of p21 Ras in the intracellular signal transduction of nerve growth factor in human neural crest-derived cell populations.

p21ras supports the survival of chick embryonic motor neurones

Various trophic factors present in muscle extract can promote the survival of cultured motor neurones. However, little is known about the signal transduction pathways used in these cells. The proto-oncogene product p21ras has been shown to play an important role in proliferative and differentiative signalling pathways. We report here that cytoplasmic introduction of its oncogenic form, p21ras(G12V), fully supports the in vitro survival of chick embryonic motor neurones. The proto-oncogenic form of p21ras also showed a dose-dependent survival effect, while a C-terminally truncated counterpart of p21ras(G12V) was ineffective. These results suggest an involvement of p21ras in signal transduction pathways leading to motor neurone survival and may be of relevance for the development of therapeutic strategies for motor neurone disease.

Active p21Ras is sufficient for rescue of NGF-dependent rat sympathetic neurons

We have examined whether p21Ras proteins can rescue nerve growth factor-deprived rat sympathetic neurons from death, to test further our hypothesis that p21Ras is a central mediator in the nerve growth factor-to-survival signalling pathway. After crosslinking [125I]nerve growth factor to live neurons, two forms of Trk (molecular weight approximately 140,000 and 115,000) were immunoprecipitated with anti-Trk antibodies. Nerve growth factor induced tyrosine phosphorylation of both Trk forms and at least two additional proteins. When these phosphorylations were prevented by staurosporine (in a protein kinase C-independent manner) the neurons died. However, neurons were rescued from death due to staurosporine treatment by intracellular loading of oncogenic Ha-Ras(val12) protein. Both Ha-Ras(val12) and cellular Ha-Ras proteins maintained survival for several days in the absence of nerve growth factor and mimicked other actions of nerve growth factor, inducing rapid c-Fos protein expression and robust neurite outgrowth. Conversely, Fab fragments of neutralizing antibodies to p21Ras which blocked the capacity of nerve growth factor to promote neuron survival were also found to inhibit the early expression of c-Fos protein in these neurons. The close correspondence observed between the timing of onset of c-Fos responsiveness and acquisition of nerve growth factor-dependence in embryonic day 17 sympathetic neurons, and the coordinate increase found in both parameters until embryonic day 19 indicates that c-Fos protein expression is a good biochemical indicator of the presence of a functional nerve growth factor-to-survival signal transduction pathway. Nevertheless, expression of c-Fos is not sufficient for survival since phorbol esters induce c-Fos with no effect on survival. These data strengthen our proposal that p21Ras proteins are crucial anti-apoptotic mediators of survival in rat sympathetic neurons by demonstrating that p21Ras is both necessary and sufficient to rescue neurons which are disabled from signalling through Trk receptors.

Chemotherapeutic activity of levofloxacin (HR 355, DR-3355) against systemic and localized infections in laboratory animals

Ofloxacin, its optical isomers levofloxacin (HR 355, DR-3355) and D-ofloxacin (DR-3354) and ciprofloxacin were administered orally to mice and rats which had systemic and localized infections. Both levofloxacin and ciprofloxacin were equally effective in treating systemic murine infections caused by staphylococci. Enterobacteriaceae or Pseudomonas aeruginosa with ED50s ranging from 0.18 to 15.8 mg/kg and 0.42 to 16.3 mg/kg respectively and both these agents were twice as effective as ofloxacin which had an ED50 0.41 to 39.7 mg/kg. In contrast, D-ofloxacin was either inactive or exhibited only modest chemotherapeutic activity against the staphylococci and the Gram-negative organisms tested. When given to mice to treat staphylococcal abscesses and lung infections due to Klebsiella pneumoniae DT-S levofloxacin was up to four times more effective and produced a more pronounced bactericidal effect against the pathogens in vivo than the reference compounds. Despite possessing a similar, if not lesser, in-vitro activity against the infecting pathogens, levofloxacin was more effective than ofloxacin and ciprofloxacin in rats with localized infections caused by Enterobacteriaceae and P. aeruginosa.

Mode of action of the lantibiotic mersacidin: inhibition of peptidoglycan biosynthesis via a novel mechanism?

Mersacidin is an antibiotic peptide produced by Bacillus sp. strain HIL Y-85,54728 that belongs to the group of lantibiotics. Its activity in vivo against methicillin-resistant Staphylococcus aureus strains compares with that of the glycopeptide antibiotic vancomycin (S. Chatterjee, D. K. Chatterjee, R. H. Jani, J. Blumbach, B. N. Ganguli, N. Klesel, M. Limbert, and G. Seibert, J. Antibiot. 45:839-845, 1992). Incubation of Staphylococcus simulans 22 with mersacidin resulted in the cessation of growth and slow lysis. Biosyntheses of DNA, RNA, and protein were not affected, whereas incorporation of glucose and D-alanine was inhibited and a regular reduction in the level of cell wall thickness was observed. Thus, unlike type A lantibiotics, mersacidin does not form pores in the cytoplasmic membrane but rather inhibits cell wall biosynthesis. Comparison with tunicamycin-treated cells indicated that peptidoglycan rather than teichoic acid metabolism is primarily affected. Mersacidin caused the excretion of a putative cell wall precursor into the culture supernatant. The formation of polymeric peptidoglycan was effectively inhibited in an in vitro assay, probably on the level of transglycosylation. In contrast to vancomycin, the activity of mersacidin was not antagonized by the tripeptide diacetyl-L-Lys-D-Ala-D-Ala, indicating that on the molecular level its mode of action differs from those of glycopeptide antibiotics. These data together with electron microscopy suggest that mersacidin acts on a novel target, which opens new perspectives for the treatment of methicillin-resistant S. aureus.

Lues maligna, or ulceronodular syphilis, in a man infected with human immunodeficiency virus: case report and review

A 30-year-old bisexual man who was infected with human immunodeficiency virus (HIV) and had a history of anaphylaxis to penicillin developed lues maligna, or ulceronodular secondary syphilis. Therapy with parenteral erythromycin failed, and he was subsequently treated with ceftriaxone following penicillin desensitization. A review of the English-language literature identified 14 cases of lues maligna reported between the early 1900s and 1988. From 1989 to 1994, an additional 12 cases (including the current case) were reported. Of those 12 cases, 11 occurred in patients who either were infected with HIV or were at high risk for HIV infection. Patients infected with HIV may be at increased risk of developing this severe form of secondary syphilis. Lues maligna should be considered in the differential diagnosis of HIV-infected patients who present with ulceronodular lesions.

Bacteremia due to fluoroquinolone-resistant Escherichia coli in two immunocompromised patients

Two patients with acute leukemia developed Escherichia coli bacteremia while receiving oral ofloxacin for antibacterial prophylaxis during profound neutropenia. The isolates were resistant to ofloxacin (MIC 25 and 12.5 micrograms/ml respectively), other fluoroquinolones and several unrelated agents. Whole cell drug accumulation studies with four different fluoroquinolones suggested major differences between drugs but only minor alterations in individual drug permeability in the two resistant isolates compared with a susceptible control strain. In a supercoiling assay using the purified DNA gyrase and plasmid pBR322, high concentrations (> or = 250 micrograms/ml) of both ofloxacin and ciprofloxacin were needed for visible inhibition of enzyme activity suggesting mutations in the DNA gyrase gene as the significant mechanism of resistance in both strains.

Involvement of ras p21 in neurotrophin-induced response of sensory, but not sympathetic neurons

Little is known about the signal transduction mechanisms involved in the response to neurotrophins and other neurotrophic factors in neurons, beyond the activation of the tyrosine kinase activity of the neurotrophin receptors belonging to the trk family. We have previously shown that the introduction of the oncogene product ras p21 into the cytoplasm of chick embryonic neurons can reproduce the survival and neurite-outgrowth promoting effects of the neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), and of ciliary neurotrophic factor (CNTF). To assess the potential signal-transducing role of endogenous ras p21, we introduced function-blocking anti-ras antibodies or their Fab fragments into cultured chick embryonic neurons. The BDNF-induced neurite outgrowth in E12 nodose ganglion neurons was reduced to below control levels, and the NGF-induced survival of E9 dorsal root ganglion (DRG) neurons was inhibited in a specific and dose-dependent fashion. Both effects could be reversed by saturating the epitope-binding sites with biologically inactive ras p21 before microinjection. Surprisingly, ras p21 did not promote the survival of NGF-dependent E12 chick sympathetic neurons, and the NGF-induced survival in these cells was not inhibited by the Fab-fragments. The survival effect of CNTF on ras-responsive ciliary neurons could not be blocked by anti-ras Fab fragments. These results indicate an involvement of ras p21 in the signal transduction of neurotrophic factors in sensory, but not sympathetic or ciliary neurons, pointing to the existence of different signaling pathways not only in CNTF-responsive, but also in neurotrophin-responsive neuronal populations.

Antibacterial activity of RU44790, a new N-tetrazolyl monocyclic beta-lactam

RU44790 belongs to a new class of synthetic monocyclic beta-lactam antibiotics which feature a bioisosteric tetrazole moiety instead of the more classical acidic functions at the N-1 position of the beta-lactam ring. Its antibacterial activity was evaluated against some 900 strains and was compared with those of other recent beta-lactam derivatives, especially aztreonam. RU44790 is endowed with potent activity against gram-negative bacteria. At less than or equal to 0.6 micrograms/ml, RU44790 inhibited 90% of all strains of the family Enterobacteriaceae with the exception of Citrobacter spp. (MIC for 90% of strains tested, 1.2 micrograms/ml). The activity was similar to that of aztreonam against strains that are normally susceptible to expanded-spectrum cephalosporins. On the other hand, the new compound was 10 to 100 times more potent than aztreonam and most of the other antibiotics tested against enterobacteria that produce chromosome-encoded or plasmid-mediated extended-spectrum beta-lactamases. Pseudomonas aeruginosa isolates were equally susceptible to both monobactams. RU44790 was inactive against staphylococci and had only marginal activity against streptococci (MIC for 50% of strains tested, 2.5 micrograms/ml). RU44790 was highly resistant to hydrolysis by various beta-lactamases, particularly cephalosporinases such as P99. The latter enzyme was also inhibited by the compound. RU44790 showed a high affinity for penicillin-binding protein 3 of Escherichia coli. The results suggest that RU44790 has good potential in the treatment of infections caused by gram-negative microorganisms.