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Background: Rickettsia helvetica, a spotted fever rickettsia, is transmitted to humans via ticks in Europe, North Africa, and Asia. The central nervous system is a crucial target for rickettsial diseases, which has been reported for 12 of the 31 species, of which R. helvetica is one. This study aimed, in an experimental model, to identify characteristics of R. helvetica infection in a mouse neuronal cell line, NSC-34., Results: NSC-34, a fusion cell line of mouse motor spinal cord neurons and neuroblastoma cells, was used as a model. Propagation of R. helvetica in neurons was confirmed. Short actin tails were shown at the polar end of the bacteria, which makes it likely that they can move intracellularly, and even spread between cells. Another protein, Sca4, which with the cell adhesion protein vinculin enables the passage of the cell membrane, was expressed during infection. No significant increase in TNFα levels was seen in the infected neurons, which is of interest because TNFα protects the host cell from infection-induced apoptotic death which is crucial for host cell survival. The bacteria were also shown to invade and grow in the cell nucleus of the neuron., Conclusions: The findings suggest that a R. helvetica infection may be harmful to NSC-34 neurons under these in vitro conditions, but the full effects of the infection on the cell need to be studied further, also on human neurons, to also understand the possible significance of this infection in relation to pathogenetic mechanisms., (© 2023. The Author(s).)

In a retrospective study, 36 patients with peripheral facial palsy were serologically evaluated for the presence of Rickettsia spp. and Borrelia spp. antibodies. All sera underwent immunofluorescence and Western blot analysis for IgG and IgM antibodies using Rickettsia helvetica and R. felis as antigens. Anti- Borrelia antibodies were detected using a commercial ELISA detecting Borrelia burgdorferi, B. afzelii and B. garinii . Three patients (8.3%) were seropositive for Rickettsia spp. with IgG titres equal to 1:128, and six patients (16.7%) had IgM titres equal to or above 1:128. All samples with IgG/IgM titres equal to or above 1:128 were confirmed by Western Blot. Four patients (11.1%) had IgG antibodies against Borrelia at a titre level normally judged to be indicative of current infection. Two of these patients had significant IgG or IgM titres for both Rickettsia spp. and Borrelia spp., indicating co-infection. In conclusion, the findings indicate current rickettsial infection or early response at about the same degree as for Lyme borreliosis in patients with facial palsy, but they need to be further examined with a larger number of patients and paired serum analyses., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Eighteen species of rickettsiae are reported to cause infections in humans. One of these is Rickettsia helvetica, which is endemic in European and Asian countries and transmitted by the tick Ixodes ricinus. Besides fever, it has been demonstrated to cause meningitis and is also associated with perimyocarditis. One of the initial targets for rickettsiae after inoculation by ticks is the macrophage/monocyte. How rickettsiae remain in the macrophages/monocytes before establishing their infection in vascular endothelial cells remains poorly understood. The main aim of the present study was to investigate the impact on and survival of R. helvetica in a human leukemic monocytic cell line, THP-1. Our results show that R. helvetica survives and propagates in the THP-1 cells. The infection in monocytes was followed for seven days by qPCR and for 30 days by TEM, where invasion of the nucleus was also observed as well as double membrane vacuoles containing rickettsiae, a finding suggesting that R. helvetica might induce autophagy at the early stage of infection. Infected monocytes induced TNF-α which may be important in host defence against rickettsial infections and promote cell survival and inhibiting cell death by apoptosis. The present findings illustrate the importance of monocytes to the pathogenesis of rickettsial disease., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Vector-borne diseases such as Lyme borreliosis and rickettsioses have been associated with ocular inflammation. Our aim was to study patients with diagnosed uveitis to evaluate serological signs of infection or exposure to these tick-borne agents. Forty-eight patients were prospectively examined with serology together with medical records and a questionnaire concerning previous exposure, diseases, and treatments. Seven patients (14.6%) showed seroconversion to Rickettsia spp. between acute and convalescent phase sera, which provides support for a positive Rickettsia diagnosis according to guidelines. The specificity was confirmed by Western blot. Additional 28 patients had stationary titres of which eight (16.6%) had 1 : 256 or higher titre in the first serum, and another 13 patients were seronegative. No epidemiological risk factor or marker could be identified. For Borrelia , only three patients showed moderate IgG titres. A control group of 100 blood donors, 60 patients with rheumatic disease, and 56 patients seeking medical care were tested of which 2.0-7.1% showed low anti- Rickettsia titres and 3.0-8.3% anti- Borrelia titres. The findings are indicative for an association between infection or exposure to Rickettsia spp. and uveitis with a seropositivity among patients with recurrent uveitis in concordance with the spread of rickettsial exposure in a tick-exposed population.

This randomized double-blind placebo controlled study assessed the vaginal colonization of lactic acid bacteria and clinical outcome. Vaginal capsules containing L gasseri LN40, Lactobacillus fermentum LN99, L. casei subsp. rhamnosus LN113 and P. acidilactici LN23, or placebos were administered for five days to 95 women after conventional treatment of bacterial vaginosis and/or vulvovaginal candidiasis. Vulvovaginal examinations and vaginal samplings were performed before and after administration, after the first and second menstruation, and after six months. Presence of LN strains was assessed using RAPD analysis. LN strains were present 2-3 days after administration in 89% of the women receiving LN strains (placebo: 0%, p < 0.0001). After one menstruation 53% were colonized by at least one LN strain. Nine percent were still colonized six months after administration. Ninety-three percent of the women receiving LN strains were cured 2-3 days after administration (placebo: 83%), and 78% after one menstruation (placebo: 71%) (ns). The intervention group experienced less malodorous discharge 2-3 days after administration (p = 0.03) and after the second menstruation (p = 0.04), compared with placebo. In summary, five days of vaginal administration of LN strains after conventional treatment of bacterial vaginosis and/or vulvovaginal candidiasis lead to vaginal colonization, somewhat fewer recurrences and less malodorous discharge., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

In samples obtained during the autopsies of 2 patients with sarcoidosis, genetic material from Rickettsia helvetica was detected by polymerase chain reaction, and histologic and immunohistochemical examination (using 3 different antibodies) of the polymerase chain reaction-positive tissues showed different degrees of granuloma formation and presence of rickettsia-like organisms predominantly located in the endothelium and macrophages. Electron microscopic examination clearly identified and demonstrated rickettsia-like organisms within the granuloma, with findings suggestive of ongoing infection. Immunogold labeling with Proteus OX-19 antiserum showed that the gold markers were localized to the rickettsia-like organisms. Paraffin-embedded biopsy specimens from 30 patients with confirmed sarcoidosis were also reexamined, and 26 specimens were judged to be positive for rickettsia-like organisms by histologic and immunohistochemical examination. In a specimen from 1 patient, rickettsia-like organisms also were demonstrated and identified by transmission electron microscopy. These results support the hypothesis that rickettsiae may contribute to a granulomatous process, as is seen in sarcoidosis.

In the present study further characterization of the amplified sequence of the citrate synthase gene of the spotted fever group Rickettsia isolated from Ixodes ricinus ticks in Sweden showed that it has 100% homology with the deposited sequence of the citrate synthase gene of Rickettsia helvetica. The restriction fragment length polymorphism (RFLP) pattern of an amplified 382-bp product of the citrate synthase sequence, defined by primers RpCS877 and RpCS1258, yielded fragments for our isolate that could be visualized as a double band that migrated at approximately 44 bp, another double band at 85 bp, and a single band at nearly 120 bp after digestion with the restriction enzyme AluI. When calculating a theoretical PCR-RFLP pattern of the sequence of the citrate synthase gene of R. helvetica from the known positions where the AluI enzyme cuts, we arrived at the same pattern that was obtained for our isolate, a pattern distinctly different from the previously published PCR-RFLP pattern for R. helvetica. Investigation of 125 living I. ricinus ticks showed a higher prevalence of rickettsial DNA in these ticks than we had found in an earlier study. Rickettsial DNA was detected by amplification of the 16S rRNA gene, for which a seminested primer system consisting of two oligonucleotide primer pairs was used. Of the 125 ticks, some were pooled, giving a total of 82 tick samples, of which 20 were found to be positive for the rickettsial DNA gene investigated. When considering the fact that some of the positive samples were pooled, the minimum possible prevalence in these ticks was 20 of 125 (16%) and the maximum possible prevalence was 46 of 125 (36.8%). These prevalence estimates conform to those of other studies of spotted fever group rickettsiae in hard ticks in Europe.

An alpha-2 proteobacterium, previously unknown as determined by its phylogenetic characteristics and the DNA sequence of its 16S rRNA gene, was isolated from a patient who presented an unusual clinical picture, including high remitting fever and multiorgan involvement. The bacterium was detected in multiple plasma samples, obtained during the acute phase of the disease, after cocultivation in cell culture media. Electron microscopy of the organism showed a three-layer laminar cell wall and electron-dense granules within the cytoplasm, as well as a polar flagellum. By means of PCR followed by sequencing of amplified 16S ribosomal DNA fragments, the bacterium was found to differ from all species for which ribosomal sequence information is available. It is here provisionally named the Rasbo bacterium. At a subsequent relapse, the bacterium was identified in pericardial fluid both by PCR/sequencing and by direct electron microscopy. At a second relapse, it was again cultured from plasma. After in vitro adaptation to solid media, the MICs of various antibiotics could be determined. A transient immunoglobulin M (IgM) but no IgG response to the bacterium was found by an indirect immunofluorescence test, as well as by an immobilization test during the acute phase of the disease.

A spotted fever group rickettsia isolated from the common tick, Ixodes ricinus, was genetically characterized by PCR and genomic sequencing. This study was performed with nymphal and adult ticks collected in southern and central Sweden. I. ricinus is the only North European tick species of medical importance which is regularly collected from humans. No species of the genus Rickettsia has previously been found in Scandinavian ticks, nor has any case of domestic rickettsial infection in humans or animals been reported. According to the nucleotide sequencing, the present Rickettsia sp. belongs to the spotted fever group of rickettsiae. Ticks are the most common arthropod reservoirs and vectors of the rickettsiae of this group. Among 748 ticks investigated, 13 (1.7%) were positive for a Rickettsia sp. Borrelia burgdorferi was detected in 52 (7%) of the ticks, a prevalence similar to or somewhat lower than that previously been recorded in other Swedish studies. There was no evidence of ehrlichial or chlamydial DNA in these ticks. The Rickettsia sp. was further characterized by 16S ribosomal DNA (rDNA) sequencing and restriction fragment length polymorphism (RFLP). The 16S rDNA sequencing resulted in a sequence identical to that described for Rickettsia helvetica, but the pattern obtained with RFLP of the citrate synthetase gene diverged from previously known patterns. The rickettsial agent of one tick which was positive by PCR was confirmed by transmission electron microscopy. The morphology of this rickettsia was similar to that of the spotted fever and typhus group rickettsiae. This represents the first documented isolate of a Rickettsia sp. from Swedish ticks.

Objective: The cure rate after treatment of bacterial vaginosis (BV) differs in various investigations, but most studies report a cure rate of 70% after 1 month., Methods: A long-term observation study after successful treatment of BV has been undertaken. The original study was a treatment study of BV and included 50 patients., Results: We were able to identify 44 of the original 50 patients. The mean follow-up time was 6.9 years (range 4.7-9 years). During this time, 21 women (48%) had been free of BV while 23 women had had relapses. There was no difference in the use of broad-spectrum antibiotics, episodes of candida vaginitis, bleeding disturbances, family planning method, development of cervical intraepithelial neoplasia (CIN), or gynecological operations between women with and without relapses. The women with relapses had had a new sexual contact more often during the observation period than women without relapses. There was no difference in hydrogen peroxide production of the lactobacilli among women with or without relapses, and survival analysis shows that most relapses occur during the first year after treatment., Conclusions: If patients are successfully treated, half of the patients will stay cured indicating that treatment is of benefit. Most relapses occur during the first year. Our results indicate that the etiology of BV might have something to do with new sexual contacts.

Background: Sixteen cases of sudden unexpected cardiac death, 15 males and one female, are known to have occurred among young Swedish orienteers from 1979 to 1992, of which seven cases occurred between 1989 and 1992. This is considered to be indicative of an increased death rate., Results: Histopathological evaluation showed myocarditis in a higher than expected proportion of cases. In one such case, which we studied before the sudden unexpected death occurred, the victim had suffered a Chlamydia pneumoniae infection verified by serology, and a nucleotide sequence was found in the heart and lung by means of the polymerase chain reaction (PCR) that hybridized with a probe specific for that organism. Male Swedish orienteers do not, however, seem to have an increased rate of exposure to this agent. No further sudden unexpected deaths among young orienteers have occurred over the past 3.5 years. At the beginning of that period, attempts were made to modify training habits and attitudes.

Objective: The production of hydrogen peroxide (H2O2) from different strains of lactobacilli in the vagina has been proposed to play one of the most important protective roles in the vaginal defense system. New data have, however, suggested that Döderlein's bacteria, with the morphological appearance of long lactobacilli, have a low production of H2O2 . The purpose of the present study was to correlate the morphology of lactobacilli with the incidence of infection following legal abortion., Methods: Seven hundred sixty-nine women with lactobacilli but without Chlamydia trachomatis or bacterial vaginosis in their vaginal wet smears who were to undergo legal abortions were divided into 6 different groups according to the morphological appearance of the lactobacilli. The postoperative infection rates in these different groups were compared. A phenotypic classification of some of the lactobacilli was performed., Results: The presence of Döderlein's bacteria compared with a mixed flora of lactobacilli increased the risk of postoperative infection 3 times [relative risk (RR) = 3.0; 95% confidence interval (CI), 1.5-6.3]. After a logistic regression analysis, the only independent risk factors were the presence of Döderlein's bacteria and earlier gestational age., Conclusions: We found that the lactobacilli regarded as commensal organisms and "normal, healthy lactobacilli" in the vagina were present in only 18% of these women and that their presence might be hazardous. Therefore, we must reconsider our concept of the "normal" lactobacilli in the vaginal wet smears of healthy women.

Primers specific to conserved and variable regions in the 16S rRNA sequence were selected from the partially sequenced 16S rRNA genes of Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, S. agalactiae, and Staphylococcus epidermidis. The PCR assay was divided into two DNA amplifications. The first resulted in a general bacterial amplicon, and the second resulted in a species-specific amplicon. The high specificity of the PCR assay was documented after testing bacteria of 28 different species (133 strains). A total of 304 clinical cerebrospinal fluid samples, including 125 samples from patients with bacterial meningitis, were assayed to investigate the diagnostic sensitivity and specificity for bacterial meningitis. The assay showed high sensitivity (0.94) and specificity (0.96) with the clinical samples, although some false results were obtained, the reasons for which are discussed. With agarose gel electrophoresis for detection of the PCR products, the detection limit for meningococci in cerebrospinal fluid was 3 x 10(2) CFU/ml.

A litCon mutation in Escherichia coli TU6 results in exclusion of bacteriophage T4 during the late, morphogenetic stage of its development at low temperatures. DNA was synthesized continuously in the infected cells, but less than 10% of the DNA made by 90 min after infection was packaged into DNAase-resistant particles, few viable phage were formed, and the cells lysed poorly. The exclusion could be relieved by conditions leading to elevated levels, determined immunologically, of the E. coli Rho protein (believed to be involved in regulation of T4 transcription), or chromosomally encoded E. coli GroEL (a chaperone known to be involved in phage assembly), or by supplying GroEL in trans from a plasmid. The two suppressing proteins appeared to act independently of each other. GroEL-suppression restored packaging to normal levels, perhaps by preventing GP23 from activating the host Lit protein; in addition DNA synthesis was delayed and reduced and cell lysis enhanced, demonstrating involvement of GroEL in both these processes. Rho suppression was less efficient. Since both transcription-termination-proficient and transcription-termination-deficient Rho suppressed, the results raise the possibility that Rho has a role during T4 development not directly involving transcription regulation.

There is need for integrated systems that provide rapid and sensitive diagnosis of Chlamydia trachomatis. Here we describe for the first time that specific antibodies to a C. trachomatis surface protein can be used for magnetic recovery of bacteria directly from crude urine samples. The combination of immunomagnetic separation (IMS), where the bacterial cells are both purified and concentrated, with a colorimetric PCR assay makes the method sensitive and suitable for routine clinical screening in microtiter format. No filtrations, centrifugations, extractions, or electrophoretic techniques are required throughout the whole procedure. Using magnetic beads as the solid phase, the colorimetric detection of immobilized amplified nucleic acids (DIANA) also allow direct DNA sequencing of positive samples for more detailed analysis. Of the 27 urine samples analyzed, eight were found to be positive using this method. Only five out of these eight were determined to be positive by cell culture.

60 women with bacterial vaginosis were entered into a double blind, placebo-controlled treatment trial with lyophilized Lactobacillus acidophilus. The lactobacilli used were producing H2O2. Immediately after completion of treatment, 16 out of 28 women who were treated with lactobacilli had normal vaginal wet smear results, in comparison to none of the 29 women treated with placebo. All women harboured Bacteroides at inclusion. Bacteroides was eliminated from the vagina of 12 out of 16 healthy women after treatment. Only three of the women who received the Lactobacillus suppository were free of bacterial vaginosis after the subsequent menstruation.

The diagnostic criteria of bacterial vaginosis (BV) and the prevalence of Mobiluncus spp as detected by monoclonal antibodies were investigated in all new women patients attending the sexually transmitted disease (STD) clinic in Uppsala during a four month period. Of 455 patients, 164 fulfilled the generally accepted criteria for BV, but in 57 of them simultaneous infection with a recognised pathogen was diagnosed. BV was thus the only clinical diagnosis in 107 (24%) of the women. The sniff test and clue cells in the wet smear were the two criteria most relevant for the diagnosis of BV. The sniff test was positive in 95% (156) of the 164 patients with BV and negative in all other cases. The corresponding figure for the clue cells was 98% (160 of 164), but clue cells were also detected in 19 patients without BV. Though 99% (162) of women with BV had a vaginal pH of more than 4.5, so did 83 women without BV. Only 59% (96) of women fulfilling the criteria of BV had a characteristic discharge. Mobiluncus spp were present in 20% (90) of the 455 women and in 50% (53) of the 107 women with BV only. Of the 90 Mobiluncus spp isolates, M curtisii comprised 44% (40), M mulieris 34% (31), and both strains together 21% (19). Mobiluncus spp were detected with monoclonal antibodies in 35 women who had no motile curved rods on wet smear microscopy. Furthermore, Mobiluncus spp were often detected in women infected with recognised pathogens, as well as in a few women without signs of genital infection.

Campylobacter pylori was identified with immunoperoxidase staining and a mouse monoclonal antibody directed against C. pylori in gastric biopsy specimens from 24 patients with gastritis. C. pylori was not found in gastric biopsy specimens from six subjects with histologically normal mucosa. The monoclonal antibody, which was reactive with a surface protein of approximately 20 kilodaltons, was found to be specific for C. pylori, and the immunoperoxidase staining proved to be more sensitive and rapid than culture in detecting the organism. In the tissue specimens where C. pylori was detected with the monoclonal antibody, there was a strong expression of class II transplantation antigens on the epithelial cells and an increased number of T lymphocytes. These findings indicate that C. pylori may initiate local immune responses.

The simultaneous occurrence of Mobiluncus spp in the vagina and rectum was studied in women attending a sexually transmitted diseases (STD) department. Of 43 women with bacterial vaginosis (BV), 32 had Mobiluncus spp in the vagina and 23 in the rectum. In 20 women the same Mobiluncus species was found concomitantly in the vagina and the rectum. Mobiluncus spp were found in the rectum only in two women with BV, one with candidal vaginitis, and one healthy woman. In a treatment study of 23 women, BV was cured in nine out of 10 treated with metronidazole and six out of 13 treated with tetracycline. After treatment Mobiluncus spp persisted in the vaginas of two out of 19 women and in the rectums of two out of 10.