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The guinea pig was the original animal model developed for investigating spotted fever rickettsiosis (SFR). This model system has persisted on account of the guinea pig's conduciveness to tick transmission of SFR agents and ability to recapitulate SFR in humans through clinical signs that include fever, unthriftiness, and in some cases the development of an eschar. The guinea pig is the smallest animal model for SFR that allows the collection of multiple blood and skin samples antemortem for longitudinal studies. This unit provides the basic protocols necessary to establish, maintain, and utilize a guinea pig-tick-Rickettsia model for monitoring the course of infection and immune response to an infection by spotted fever group Rickettsia (SFGR) that can be studied at biosafety level 2 (BSL-2) and arthropod containment level 2 (ACL-2); adaptations must be made for BSL-3 agents. The protocols cover methods for tick feeding and colony development, laboratory infection of ticks, tick transmission of Rickettsia to guinea pigs, and monitoring of the course of infection through clinical signs, rickettsial burden, and immune response. It should be feasible to adapt these methods to study other tick-borne pathogens. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Tick transmission of SFGR to guinea pigs Support Protocol 1: Laboratory infection of ticks by injection Alternate Protocol 1: Needle inoculation of SFGR to guinea pigs Basic Protocol 2: Monitoring the course of guinea pig rickettsial infection: clinical signs Basic Protocol 3: Monitoring the course of guinea pig rickettsial infection: collection of biological specimens Support Protocol 2: Guinea pig anesthesia Basic Protocol 4: Monitoring rickettsial burden in guinea pigs by multiplex qPCR Basic Protocol 5: Monitoring guinea pig immune response to infection: blood leukocytes by flow cytometry Basic Protocol 6: Monitoring immune response to guinea pig rickettsial infection: leukocyte infiltration of skin at the tick bite site by flow cytometry Basic Protocol 7: Monitoring the immune response to guinea pig rickettsial infection: antibody titer by ELISA Support Protocol 4: Coating ELISA Plates Alternate Protocol 2: Monitoring immune response to guinea pig rickettsial infection: antibody titer by immunofluorescence assay.

Members of the genus Rickettsia range from nonpathogenic endosymbionts to virulent pathogens such as Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever. Many rickettsiae are considered nonpathogenic because they have been isolated from ticks but not vertebrate hosts. We assessed the ability of three presumed endosymbionts: Rickettsia amblyommatis, Rickettsia bellii, and Rickettsia montanensis, to infect a guinea pig animal model. These species were chosen because of their high prevalence in respective tick vectors or published reports suggestive of human or animal pathogenicity. Following intraperitoneal (IP) inoculation of cell culture suspensions of R. rickettsii, R. amblyommatis, R. bellii, or R. montanensis into guinea pigs, animals were monitored for signs of clinical illness for 13 days. Ear biopsies and blood samples were taken at 2- to 3-day intervals for detection of rickettsial DNA by PCR. Animals were necropsied and internal organ samples were also tested using PCR assays. Among the six guinea pigs inoculated with R. amblyommatis, fever, orchitis, and dermatitis were observed in one, one, and three animals respectively. In R. bellii-exposed animals, we noted fever in one of six animals, orchitis in one, and dermatitis in two. No PCR-positive tissues were present in either the R. amblyommatis- or R. bellii-exposed groups. In the R. montanensis-exposed group, two of six animals became febrile, two had orchitis, and three developed dermatitis in ears or footpads. R. montanensis DNA was detected in ear skin biopsies collected on multiple days from three animals. Also, a liver specimen from one animal and spleen specimens of two animals were PCR positive. The course and severity of disease in the three experimental groups were significantly milder than that of R. rickettsii. This study suggests that the three rickettsiae considered nonpathogenic can cause either subclinical or mild infections in guinea pigs when introduced via IP inoculation.

The Amblyomma maculatum Koch group of ixodid ticks consists of three species: A. maculatum, A. triste, and A. tigrinum. However, since Koch described this group in 1844, the systematics of its members has been the subject of ongoing debate. This is especially true of A. maculatum and A. triste; recent molecular analyses reveal insufficient genetic divergence to separate these as distinct species. Further confounding this issue is the discovery in 2014 of A. maculatum group ticks in southern Arizona (AZ), USA, that share morphological characteristics with both A. triste and A. maculatum. To biologically evaluate the identity of A. maculatum group ticks from southern Arizona, we analyzed the reproductive compatibility between specimens of A. maculatum group ticks collected from Georgia (GA), USA, and southern Arizona. Female ticks from both Arizona and Georgia were mated with males from both the Georgia and Arizona Amblyomma populations, creating two homologous and two heterologous F1 cohorts of ticks: GA ♀/GA ♂, AZ ♀/AZ ♂, GA ♀/AZ ♂, and AZ ♀/GA ♂. Each cohort was maintained separately into the F2 generation with F1 females mating only with F1 males from their same cohort. Survival and fecundity parameters were measured for all developmental stages. The observed survival parameters for heterologous cohorts were comparable to those of the homologous cohorts through the F1 generation. However, the F1 heterologous females produced F2 egg clutches that did not hatch, thus indicating that the Arizona and Georgia populations of A. maculatum group ticks tested here represent different biological species.

The human Fc-gamma receptors (FcγRs) link adaptive and innate immunity by binding immunoglobulin G (IgG). All human low-affinity FcγRs are encoded by the FCGR2/3 locus containing functional single nucleotide polymorphisms (SNPs) and gene copy number variants. This locus is notoriously difficult to genotype and high-throughput methods commonly used focus on only a few SNPs. We performed multiplex ligation-dependent probe amplification for all relevant genetic variations at the FCGR2/3 locus in >4,000 individuals to define linkage disequilibrium (LD) and allele frequencies in different populations. Strong LD and extensive ethnic variation in allele frequencies was found across the locus. LD was strongest for the FCGR2C-ORF haplotype (rs759550223+rs76277413), which leads to expression of FcγRIIc. In Europeans, the FCGR2C-ORF haplotype showed strong LD with, among others, rs201218628 (FCGR2A-Q27W, r 2 = 0.63). LD between these two variants was weaker (r 2 = 0.17) in Africans, whereas the FCGR2C-ORF haplotype was nearly absent in Asians (minor allele frequency 2 = 0.08) in Europeans. We evaluated the importance of ethnic variation and LD in Kawasaki Disease (KD), an acute vasculitis in children with increased incidence in Asians. An association of rs1801274 with KD was previously shown in ethnically diverse genome-wide association studies. Now, we show in 1,028 European KD patients that the FCGR2C-ORF haplotype, although nearly absent in Asians, was more strongly associated with susceptibility to KD than rs1801274 in Europeans. Our data illustrate the importance of interpreting findings of association studies concerning the FCGR2/3 locus with knowledge of LD and ethnic variation.

Ehrlichia ewingii is the causative agent of human and canine granulocytic ehrlichiosis. Since its discovery in 1970, little work has been done to characterize the pathogen or study the transmission dynamics due to the inability to grow the agent in vitro. The aim of this study was to assess the suitability of multiple cell lines and media formulations for propagation of E. ewingii in cell culture. In this study, we present an overview of attempts to isolate E. ewingii from the buffy coat of goats naturally infected by Amblyomma americanum ticks, as well as a methodology for maintaining the pathogen for up to 16 weeks in culture. The most promising results were seen with HL-60 cells differentiated by the addition of 1.5% DMSO to the media and supplemented with 8 mM l-glutamine. Cultures were passaged multiple times, and fluorescence and morulae were observed by indirect fluorescent antibody test and Diff-Quik staining. It is our hope that this information will provide a foundation for future attempts to propagate and maintain E. ewingii in cell culture.

The Ehrlichia muris-like agent (EMLA) is a newly recognized human pathogen found in Wisconsin and Minnesota. Ecological investigations have implicated both the blacklegged tick, Ixodes scapularis, and the white-footed mouse, Peromyscus leucopus, as playing roles in the maintenance of EMLA in nature. The work presented here shows that I. scapularis is an efficient vector of EMLA in a laboratory mouse model, but that Dermacentor variabilis, another frequent human biting tick found in EMLA endemic areas, is not. Additionally, I. scapularis larvae are able to acquire EMLA through co-feeding with infected nymphs. As EMLA only persists in mouse blood for a relatively short period of time, co-feeding transmission may play an important role in the maintenance of EMLA in ticks, and subsequently may play a role in limiting the geographic distribution of this pathogen in areas where co-feeding of larvae and nymphs is less common.

The human Fc-gamma receptors (FcγRs) link adaptive and innate immunity by binding immunoglobulin G (IgG). All human low-affinity FcγRs are encoded by the FCGR2/3 locus containing functional single nucleotide polymorphisms (SNPs) and gene copy number variants. This locus is notoriously difficult to genotype and high-throughput methods commonly used focus on only a few SNPs. We performed multiplex ligation-dependent probe amplification for all relevant genetic variations at the FCGR2/3 locus in >4,000 individuals to define linkage disequilibrium (LD) and allele frequencies in different populations. Strong LD and extensive ethnic variation in allele frequencies was found across the locus. LD was strongest for the FCGR2C-ORF haplotype (rs759550223+rs76277413), which leads to expression of FcγRIIc. In Europeans, the FCGR2C-ORF haplotype showed strong LD with, among others, rs201218628 (FCGR2A-Q27W, r2 = 0.63). LD between these two variants was weaker (r2 = 0.17) in Africans, whereas the FCGR2C-ORF haplotype was nearly absent in Asians (minor allele frequency

Tickborne rickettsial diseases continue to cause severe illness and death in otherwise healthy adults and children, despite the availability of low-cost, effective antibacterial therapy. Recognition early in the clinical course is critical because this is the period when antibacterial therapy is most effective. Early signs and symptoms of these illnesses are nonspecific or mimic other illnesses, which can make diagnosis challenging. Previously undescribed tickborne rickettsial diseases continue to be recognized, and since 2004, three additional agents have been described as causes of human disease in the United States: Rickettsia parkeri, Ehrlichia muris-like agent, and Rickettsia species 364D. This report updates the 2006 CDC recommendations on the diagnosis and management of tickborne rickettsial diseases in the United States and includes information on the practical aspects of epidemiology, clinical assessment, treatment, laboratory diagnosis, and prevention of tickborne rickettsial diseases. The CDC Rickettsial Zoonoses Branch, in consultation with external clinical and academic specialists and public health professionals, developed this report to assist health care providers and public health professionals to 1) recognize key epidemiologic features and clinical manifestations of tickborne rickettsial diseases, 2) recognize that doxycycline is the treatment of choice for suspected tickborne rickettsial diseases in adults and children, 3) understand that early empiric antibacterial therapy can prevent severe disease and death, 4) request the appropriate confirmatory diagnostic tests and understand their usefulness and limitations, and 5) report probable and confirmed cases of tickborne rickettsial diseases to public health authorities.

Panola Mountain Ehrlichia (PME) has been suggested as an emerging pathogen of humans and dogs. Domestic goats and white-tailed deer (Odocoileus virginianus) are also susceptible and likely serve as reservoirs. Experimentally, both the lone star tick (Amblyomma americanum (L.)) and the Gulf Coast tick (Amblyomma maculatum Koch) can transmit PME among deer and goats. In the current study, we detected PME in adult wild-caught A. maculatum from the United States and Amblyomma variegatum (F.) from the Caribbean and Africa. This significantly expands the range, potential tick vectors, and risk for exposure to PME.

The human FCGR2/3 locus contains highly homologous genes encoding the five major receptors for IgG (Fc-gamma receptors, FcγRs). In two prior GWAS on Kawasaki disease (KD), a SNP in FCGR2A (131H>R; rs1801274) was identified to be associated with disease susceptibility. However, the FCGR2/3 locus contains multiple single nucleotide polymorphisms (SNPs) and copy number variations (CNVs), which were not covered by the detection platforms used in the GWAS. In this study we therefore focused on further fine-mapping of this locus to investigate the association of the different genetic variations with KD susceptibility. A highly accurate and validated multiplex ligation-dependent probe amplification (MLPA) assay was used to analyze all functionally relevant SNPs and CNVs within this locus. In a genetic association study involving case-control and family-based testing with 1028 patients with KD, the previous finding of FCGR2A-131H as a susceptibility marker for KD was confirmed (OR 1.16; 95%CI 1.08-1.32, meta-P = 0.01). In addition, we found a novel significant association of the FCGR2C-ORF haplotype with susceptibility to KD (OR 1.34; 95% confidence interval 1.11-1.62, meta-P = 0.003). FCGR2C-ORF leads to the expression of an extra, functionally activating FcγR (i.e. FcγRIIc) on myeloid cell types and NK cells. Being absent in Asian individuals, the FCGR2C-ORF haplotype only contributed to KD susceptibility in European subjects, independent of the established association with FCGR2A-H131R. We did not find any significant association of CNV of the locus with susceptibility to KD. Our data point to an important role of the activating FcγRs in KD pathology. We hypothesize that the identified functional SNPs might alter the balance between the activating and inhibitory FcγRs leading to unbalanced inflammation and KD.

We describe an infant with trisomy of (5)(p10p13.1) resulting from a de novo marker chromosome. The marker's origin was identified by chromosome microdissection and reverse in situ hybridization. The clinical findings are compared to those of other partial and complete 5p duplications. This case further defines the critical region of 5p trisomy syndrome to proximal 5p.

We construct a separable metric space E in R 3 for which both the small and large compactness degrees cmp E= Cmp E=1 and the compactness deficiency def E=2 . This improves on the example in R 4 given by R. Pol (1992) as a counterexample to the well-known conjecture of J. de Groot.

We studied the prevalence of Borrelia burgdorferi and the agent of human granulocytic ehrlichiosis (HGE) among questing nymphal and adult Ixodes scapularis ticks of the same generation and the infectivity of wild white-footed mice for ticks feeding on them. The prevalence of B. burgdorferi infection in host-seeking ticks increased less than twofold from nymphal (31% to 33%) to adult (52% to 56%) stage, and 52% of white-footed mice were infected. Prevalence of the agent of HGE increased 4.5- to 10.6-fold from nymphal (1.5% to 1.8%) to adult stage (7.6% to 19.0%), while only 18% of mice were infectious to ticks. B. burgdorferi infection was more common in mouse-fed ticks than in ticks collected from vegetation, whereas the agent of HGE was half as common in mouse-fed ticks as in ticks collected from vegetation. The different prevalence in nature of these pathogens in ticks suggests that their maintenance cycles are also different.

The intensity of Borrelia burgdorferi transmission in nature is dependent upon the efficiency of acquisition of spirochetes by larval Ixodes scapularis Say (= I. dammini Spielman, Clifford, Piesman & Corwin). White-footed mice infected with B. burgdorferi were infested weekly for 5 consecutive weeks with 25 or 250 larval I. scapularis. Prevalence of infection in nymphs derived from larvae fed at high density (25.0–38.9%) was consistently higher than in nymphs derived from larvae fed at low density (6.7–23.5%). Spirochete prevalence in nymphal I. scapularis populations in nature may be influenced by larval population density.

We describe a brother and sister with a unique combination of skeletal findings including camptodactyly (phalangeal dislocations), facial anomalies, neonatal respiratory problems, and feeding problems due to poor suck. Metaphyseal splaying, osteopenia, endosteal bone apposition, campomelia, and multiple fractures characterize the other skeletal abnormalities. The parents are first cousins once removed and are unaffected. These cases appear to represent a previously undescribed autosomal recessive disorder.

The X-linked developmental mouse mutations bare patches (Bpa) and striated (Str) may be homologous to human X-linked dominant chondrodysplasia punctata (CDPX2) and incontinentia pigmenti (IP2), respectively, based on their genetic mapping and clinical phenotypes. Bpa and Str have been localized to an overlapping critical region of 600 kb that demonstrates conserved gene order with loci in human Xq28 between DXS1104 and DXS52. As part of efforts to isolate the genes involved in these disorders, we have begun to develop a comparative transcription map spanning this region in both species. Using techniques of cross-species conservation and hybridization, exon trapping, and cDNA selection we have identified four known genes or members of gene families--caltractin, a member of the gamma-aminobutyric acid (GABAA) receptor gene family, a member of the melanoma antigen gene (MAGE) family, and several members of the murine-specific, X-linked lymphocyte regulated gene (Xlr3) family. Trapped exons and, in some cases, longer cDNAs have been isolated for potentially 7-9 additional genes. One cDNA demonstrates highly significant homology with members of the Krüppel family of zinc finger transcription factors. A second novel cDNA demonstrates homology at the 3' end of the predicted amino acid sequence to a LIM domain consensus. Gene order appears conserved among those cDNAs determined to be present in both human and mouse. Three of the murine transcripts appear to be present in multiple copies within the Bpa/Str critical region and could be associated with a predisposition to genomic rearrangements. Reverse transcriptase PCR (RT-PCR) and Northern analysis demonstrate that several of the transcripts are expressed in mid-gestation murine embryos and neonatal skin, making them candidates for the Bpa and Str mutations and their respective homologous human disorders.

Eosinophilia-myalgia syndrome (EMS) is a recently described clinical entity that has been ascribed to taking over-the-counter preparations of the amino acid L-tryptophan. We describe 4 patients with EMS, 3 of whom presented with eosinophilic fasciitis, and we review the epidemiology of EMS reported in Maryland and discuss the possible pathophysiology of the disease. EMS should be considered in the differential diagnosis of severe myalgia, eosinophilia, and eosinophilic fasciitis.

Laboratory mice, Mus musculus (L.), BALB/c strain, were assessed for their ability to develop resistance to repeated infestation by Amblyomma americanum (L.) ticks. Mice were infested five consecutive times with A. americanum nymphs. No decrease in tick viability was seen after five infestations, suggesting that BALB/c mice do not develop immune-mediated resistance to A. americanum. In contrast, tick viability was significantly reduced in the second infestation of a New Zealand White rabbit, a laboratory animal known to develop resistance to A. americanum.

We describe a newborn with a novel interstitial deletion of the long arm of chromosome 17 [del (17) (q23.2q24.3)] who died on day of life 17 during a recurrent apneic episode. Her phenotype included severe growth retardation, multiple facial anomalies, maldeveloped oralpharyngeal structures, and digital and widespread skeletal anomalies. This patient's phenotype was compared to two other reported patients with deletion 17q with minor clinical overlap consistent with a unique deletion. © 1995 Wiley-Liss, Inc.

Agents of Lyme disease (Borrelia burgdorferi) and human granulocytic ehrlichiosis (Ehrlichia phagocytophila) are perpetuated in a natural cycle involving the black-legged tick (Ixodes scapularis) and its vertebrate hosts. Using I. scapularis nymphs as the mode of infectious challenge, we studied how infection with one pathogen in white-footed mice (Peromyscus leucopus) affects their ability to acquire the other agent and subsequently to infect larvae, which these agents would do in nature. Two groups of mice were infected with either B. burgdorferi or E. phagocytophila. One week later, B. burgdorferi-infected mice were challenged with E. phagocytophila, and E. phagocytophila-infected mice were challenged with B. burgdorferi. Simultaneously, two control groups of uninfected mice were infected with each agent from the same tick cohorts used on the first groups of mice. Uninfected I. scapularis larvae were fed on all mice for xenodiagnosis at weekly intervals lasting 2 months. For the B. burgdorferi challenge, all control and E. phagocytophila-infected mice acquired B. burgdorferi. However, fewer xenodiagnostic larvae acquired B. burgdorferi from mice with mixed infections compared with mice infected with B. burgdorferi only. For the E. phagocytophila challenge, all five control mice acquired E. phagocytophila, but only two of five mice infected with B. burgdorferi subsequently acquired E. phagocytophila. Consequently, mice with both infections produced fewer xenodiagnostic ticks infected with E. phagocytophila than mice infected with E. phagocytophila only. Thus, a primary infection with either B. burgdorferi or E. phagocytophila in mice inhibited transmission of a second agent, suggesting interference between these two agents.

The agents of Lyme disease ( Borrelia burgdorferi ) and human granulocytic ehrlichiosis ( Ehrlichia phagocytophila ) are both transmitted by the tick Ixodes scapularis . In nature, ticks are often infected with both agents simultaneously. We studied whether previous infection with either Borrelia or Ehrlichia in ticks would affect acquisition and transmission of a second pathogen. Ehrlichia -infected I. scapularis nymphs were fed upon Borrelia -infected mice, and Borrelia -infected I. scapularis nymphs were fed upon Ehrlichia -infected mice. The efficiency with which previously infected nymphal ticks acquired a second pathogen from infected hosts was compared to that of uninfected ticks. An average of 51% ± 15% of ticks acquired Ehrlichia from infected mice regardless of their prior infection status with Borrelia . An average of 85% ± 10% of ticks acquired Borrelia from infected mice regardless of their prior infection status with Ehrlichia . Also, we assessed the efficiency with which individual nymphs could transmit either agent alone, or both agents simultaneously, to individual susceptible hosts. An average of 76% ± 9% of Borrelia -infected ticks and 84% ± 10% of Ehrlichia -infected ticks transmitted these agents to mice regardless of the presence of the other pathogen. There was no evidence of interaction between the agents of Lyme disease and human granulocytic ehrlichiosis in I. scapularis ticks. The presence of either agent in the ticks did not affect acquisition of the other agent from an infected host. Transmission of the agents of Lyme disease and human granulocytic ehrlichiosis by individual ticks was equally efficient and independent. Dually infected ticks transmitted each pathogen to susceptible hosts as efficiently as ticks infected with only one pathogen.

Infection with Ehrlichia phagocytophila in white-footed mice is transient and followed by a strong immune response. We investigated whether the presence of acquired immunity against E. phagocytophila precludes white-footed mice from further maintenance of this agent in nature. Mice were infected with E. phagocytophila via tick bite and challenged either 12 or 16 weeks later by Ixodes scapularis nymphs infected with the same agent. Xenodiagnostic larvae fed upon each mouse simultaneously with challenging nymphs and 1 week thereafter. Ticks were tested for the agent by PCR, and the prevalence of infection was compared to that in ticks that fed upon nonimmune control mice. Only 30% of immunized mice sustained cofeeding transmission of E. phagocytophila between simultaneously feeding infected and uninfected ticks, compared to 100% of control mice. An average of 6.3% of xenodiagnostic ticks acquired Ehrlichia from previously immunized mice when fed 1 week after the challenge, compared to 82.5% infection in the control group. Although an immune response to a single infection with E. phagocytophila in white-footed mice provided only partial protection against reinfection with the same agent, the majority of mice were rendered reservoir incompetent for at least 12 to 16 weeks. Immunity acquired by mice during I. scapularis nymphal activity in early summer may exclude a large proportion of the mouse population from maintaining E. phagocytophila during the period of larval activity later in the season.

Vector competence of Ixodes scapularis Say and Dermacentor variabilis Say for the agent of human granulocytic ehrlichiosis (HGE) was compared. Five white-footed mice, Peromyscus leucopus Rafinesque, were inoculated intra-peritoneally with blood from a mouse infected with the agent of HGE. Approximately 100 I. scapularis and D. variabilis larvae were placed on each mouse and allowed to feed to repletion. Fed larvae were collected, separated according to species and allowed to molt to nymphs. Twenty-six per cent of I. scapularis (34/131) and 11% of D. variabilis (11/96) tested positive for the agent of HGE by polymerase chain reaction (PCR) after molting to nymphs. Positive I. scapularis nymphs transmitted the agent of HGE to P. leucopus mice in 5 of 5 trials. In contrast, the positive D. variabilis nymphs did not transmit the agent of agent of HGE in any of 6 trials. In a 2nd experiment, 3 P. leucopus mice were infested with I. scapularis nymphs that were infected with the agent of HGE. All 3 mice became infected with the agent of HGE and approximately 300 D. variabilis larvae were placed on each mouse and allowed to feed to repletion. Larvae were collected and allowed to molt to nymphs as before. Approximately 8% (5/60) of the nymphs became positive for the agent of HGE as determined by PCR. Twenty-five of these nymphs were then placed on each of 9 P. leucopus mice and allowed to feed to repletion. Evidence of transmission was not observed in any of 9 mice exposed to D. variabilis nymphs. These results demonstrate that although I. scapularis is a competent vector of the agent of the HGF, D. variabilis is not.

Mutations in transcriptional regulator ATRX establish the functional significance of a PHD-like domain.

We present a patient with severe idiopathic aplastic anemia with no previous chromosomal abnormalities who developed trisomy 21 and monosomy 7 during treatment with intravenous (i.v.) cyclosporine. The abnormal karyotype disappeared when the drug was changed to the oral form. This cytogenetic aberration, previously unreported in association with cyclosporine, may reflect either a direct drug effect or the emergence of a hidden myelodysplastic cell clone subject to preferential survival during immunosuppression.

The inclusion and polymerization of the diene monomers 2,3-dimethylbutadiene, isoprene, trans-piperylene, trans-2-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, chloroprene, 1,3-cyclohexadiene, 2,3-di-dimethylbutadiene/isoprene, isoprene/trans-piperylene, and isoprene/butadiene within the tunnels of clathrates formed by tri(o-phenylenedioxy)cyclotriphosphazene have been achieved. The polymerizations were accomplished by 60 Co γ-irradiation. All the polymers obtained by this technique resulted from 1,4-addition

An epidemic of acute prolonged febrile respiratory disease affecting nine of 19 workers on a Maryland State bridge maintenance crew was diagnosed as histoplasmosis by serologic testing in all and by isolation of the organism in one. In our investigation, it was revealed that work on a particular bridge was associated with disease. Culture of bat guano from the site two months later revealed H. capsulatum. Four previously uninfected epidemiologic investigators also became ill with histoplasmosis following collection of soil and bat guano. This outbreak reveals that bats and bat guano are a source of histoplasmosis, suggests that only brief exposure is necessary for acute infection and reemphasizes that histoplasmosis is not confined to the midwestern states.

• A patient with features of a focal encephalitis was found to have isolated cerebral phycomycosis. No risk factors for phycomycosis were present, and the diagnosis was made by brain biopsy.

Die aus dimeren Cyclopentadienyldicarbonyl-Ru oder -Fe durch Reduktion mit Na/K-Legierung in THF gebildeten monomeren Anionen reagieren mit Hexafluorocyclotriphosphazen (II) unter Substitution von einem oder zwei Fluoriden zu den Produkten (I) bzw. (III).