Prevalence and genetic characterization of a Babesia microti-like species in the North American river otter (Lontra canadensis).

A 4.5-month-old, male, North American river otter (Lontra canadensis) from Athens-Clarke County, Georgia, USA being temporarily housed at a rehabilitation facility, presented with a three-day history of lethargy, anorexia, and severe anemia. Antemortem blood smears revealed intraerythrocytic piroplasms. Supportive care and antiparasitic treatments were initiated, but the animal died three days following presentation. Gross necropsy revealed yellow discoloration of all adipose tissue throughout the carcass and a mildly enlarged, diffusely yellow to pale orange liver. Microscopically, moderate, centrilobular hepatocellular degeneration and necrosis were observed, consistent with hypoxia secondary to apparent hemolytic anemia. Piroplasms were frequently observed in red blood cells in histologic sections. The nearly full-length 18S rRNA gene sequence (1588 bp) was identical to a previously described piroplasm from North American river otters from North Carolina. Phylogenetically, based on the 18S rRNA gene sequence, the otter Babesia sp. was in a sister group with a clade that included several strains of Babesia microti-like species including Babesia sp. from badgers (Meles meles), Babesia vulpes, and Babesia sp. from raccoons (Procyon lotor). To better understand the distribution and genetic variability of this Babesia species, otters from four states in the eastern U.S. and California were tested. Overall, 30 of 57 (53%) otters were positive for Babesia sp. None of four otters from California were positive, but prevalences in eastern states were generally high, 5/9 (55%) in Georgia, 7/14 (50%) in South Carolina, 10/17 (59%) in North Carolina, and 8/13 (62%) in Pennsylvania). Partial 18S rRNA gene sequences from all populations were identical to the clinical case sequence. No Babesia sensu stricto infections were detected. There were six unique COI sequences (937 bp) detected in 18 positive otters. The most common lineage (A) was detected in 12 of 18 (67%) samples from Georgia, North Carolina, South Carolina, and Pennsylvania. Lineage B was found in two otters and the remaining lineage types were found in single otters. These six lineages were 99-99.8% similar to each other and were < 88% similar to related parasites such as B. vulpes, B. microti-like species of raccoons, B. microti, and B. rodhaini. Phylogenetically, the Babesia sp. of otters grouped together in a well-supported clade separate from a sister group including B. vulpes from fox (Vulpes vulpes) and domestic dogs. In conclusion, this report demonstrates that this piroplasm is a potential pathogen of North American river otters and the parasite is widespread in otter populations in the eastern United States.

Contractile proteins in pericytes. I. Immunoperoxidase localization of tropomyosin.

In these studies we have compared the relative amounts and isoforms of tropomyosin in capillary and postcapillary venule pericytes, endothelial cells, and vascular smooth muscle cells in four rat microvascular beds: heart, diaphragm, pancreas, and the intestinal mucosa. The results, obtained by in situ immunoperoxidase localization, indicate that (a) tropomyosin is present in capillary and postcapillary venule pericytes in relatively high concentration; (b) the tropomyosin content of pericytes appears to be somewhat lower than in vascular smooth muscle cells but higher than in endothelia and other vessel-associated cells; and (c) pericytes, unlike endothelia and other nonmuscle cells, contain detectable levels of tropomyosin immunologically related to the smooth muscle isoform. These results and our previous findings concerning the presence of a cyclic GMP-dependent protein kinase (Joyce, N., P. DeCamilli, and J. Boyles, 1984, Microvasc. Res. 28:206-219) in pericytes demonstrate that these cells contain significant amounts of at least two proteins important for contraction regulation. Taken together, the evidence suggests that pericytes are contractile elements related to vascular smooth muscle cells, possibly involved, as are the latter, in the regulation of blood flow through the microvasculature.

Contractile proteins in pericytes. II. Immunocytochemical evidence for the presence of two isomyosins in graded concentrations.

This paper describes the localization of isomyosins in the pericytes of four rat microvascular beds: heart, diaphragm, pancreas, and the intestinal mucosa, by use of immunoperoxidase techniques and IgGs specific for either nonmuscle or smooth muscle isoforms. Based on the semiquantitative nature of the peroxidatic reaction, we concluded that the amount and distribution of these isoforms vary with the microvascular bed and also with vascular segments within the same bed. In the pericytes of small capillaries, nonmuscle isomyosin is the predominant form, whereas the smooth muscle isomyosin is present in very low concentration. A reversed relationship is found in the pericytes associated with larger capillaries and postcapillary venules. These results, taken together with previous findings on actin (Herman, I., and P. A. D'Amore, 1983, J. Cell Biol. 97:278a), tropomyosin (Joyce, N. C., M. F. Haire, and G. E. Palade, 1985, J. Cell Biol. 100:1379-1386), and cyclic GMP-dependent protein kinase (Joyce, N., P. DeCamilli, and J. Boyles, 1984, Microvasc. Res. 28:206-219), indicate that pericytes contain proteins essential for contraction in higher concentration than any other cells associated with the microvasculature, except smooth muscle cells. Pericytes appear to be, therefore, cells differentiated for a contractile function within the microvasculature.

Viral antibody titers. Comparison in patients with multiple sclerosis and rheumatoid arthritis.

Higher titers of antibodies to measles virus envelope antigens, hemolysin and hemagglutinin, Epstein-Barr virus (EBV) capsid antigen and nuclear antigen, and rubella virus hemagglutinin were demonstrated in serum samples of patients with multiple sclerosis and rheumatoid arthritis than in age- and sex-matched control subjects. A significant correlation was observed between antibodies to measles and rubella viruses both in patients with multiple sclerosis and rheumatoid arthritis, but such a correlation was not observed between antibodies to EBV and measles or rubella viruses. Whether elevated levels of antibodies to EBV are due to reactivation of the virus, or elevated levels of antibodies to all the enveloped viruses result from cross-reactions between viruses and host tissue, or perhaps reflect defects in immunoregulation, needs further investigation.

The use of indirect immunofluorescence to evaluate the gel filtration method of fractionating human immunoglobulins.

The indirect immunofluorescent technique has been shown to be a more sensitive method than either immunoelectrophoresis or gel filtration for testing the efficacy of the gel filtration method in fractionating human immunoglobulins. It has been confirmed that IgM fractions of some sera from patients with multiple sclerosis, contain antibody which reacts with measles virus-infected tissue culture cells.

Increased incidence of IgM class smooth muscle antibody in patients after renal transplantation.

Autoantibodies were examined in 70 patients with renal failure, before acceptance on a hemodialysis program, during the program, and up to 3 months after renal transplantation. Smooth muscle antibody (SMA) in the IgM class was detected in 76% of the patients after transplantation compared with 14% before transplantation. This increase was significant at the 5% level. Furthermore, two groups of patients were distinguished on the basis of a 4-fold or greater increase or no demonstrable increase in the titer of IgM SMA after transplantation. Rejection episodes occurred more frequently amongst patients from this former group (67%) compared with the latter group (35%).

Transient expression of the basic helix-loop-helix protein NSCL-2 in the mouse cerebellum during postnatal development.

The spatio-temporal expression of the basic helix-loop-helix transcription factor NSCL-2 was analyzed in the postnatal development of the murine brain by in situ hybridization. We found that NSCL-2 is transiently expressed in the cerebellum. NSCL-2 was found exclusively in the premigratory zone of the external granule layer where postmitotic neurons undergo initial stages of neuronal differentiation. NSCL-2 expression was not detected in mature neurons. This pattern of expression suggests that NSCL-2 is critical for the onset of neuronal differentiation, but not for the maintenance of the differentiated state.

Antibodies specific for measles virus envelope antigens and autoantibodies in patients with chronic active hepatitis.

Distinctly increased levels of antibodies to measles virus envelope antigens haemolysin and haemagglutinin were found in the sera of patients with chronic active hepatitis compared with a normal control group, using immunofluorescence and functional tests. Similarly, a higher incidence of smooth muscle antibody of both IgG and IgM classes was observed in the patients and an important correlation was found between haemolysin antibodies specific for measles virus and smooth muscle antibody of IgG and IgM classes. In contrast, there was no such correlation between the virus specific haemolysin antibodies and antinuclear antibodies. The increased levels of antibodies to measles virus envelope antigens and of autoantibodies may reflect defects in immunoregulation rather than persistent infection with measles virus.

Diversity of autoantibodies in patients with antimitochondrial antibody and their diagnostic value.

A retrospective analysis of clinical and laboratory features of 102 patients, whose sera contained antibody to mitochondria, showed that primary biliary cirrhosis was diagnosed in 50% of them. Immunofluorescence showed that the sera of the patients with primary biliary cirrhosis all had the M2 antimitochondrial antibody staining pattern. A new staining pattern, designated M2(1), which could be mistaken for the M2 pattern, was not found in any patients with either primary biliary cirrhosis or chronic active hepatitis. Other serological variables such as antibody to mitochondria in IgM class, to multiple nuclear dots, and to the XR antigen, were associated with primary biliary cirrhosis, and taken in association with antimitochondrial antibody of M2 type, contribute to the diagnosis of the disease.

Xerox telecopier transmission of fetal monitor tracings: a 4-year experience.

A telephone consultation system using the Xerox 400 Telecopier has been established to transmit fetal monitor data to a tertiary center from regional hospitals with limited experience in interpreting this data. This report reviews a 4-year experience with this consultative device, discusses both the advantages and disadvantages of such a program, and recommends the establishment of similar services in other tertiary centers. We believe that the establishment of such services can be of diagnostic and therapeutic benefit to inexperienced medical personnel when first confronted with the concept of fetal monitoring. Hopefully, by so doing, hospital use of fetal monitoring will increase.

Distribution of measles antigen and immunoglobulin-containing cells in the CNS in subacute sclerosing panencephalitis (SSPE) and atypical measles encephalitis.

The immunoperoxidase technique has been used to study the distribution of measles virus antigen and immunoglobulin (Ig)-containing cells within the CNS, in 5 cases of subacute sclerosing panencephalitis (SSPE) and 1 case of atypical measles encephalitis. Measles virus antigen was demonstrated within the brain in all cases, and in the spinal cord in 1 case of SSPE. Ig-containing cells were also demonstrated in all cases, the proportions of the different light and heavy chain types varying somewhat from case to case. In SSPE IgG constituted the major and IgA the principal minor heavy chain demonstrated. In all cases of SSPE there was significant excess of light-chain-containing over heavy-chain-containing cells. In the case of atypical measles encephalitis there was a paucity of Ig-containing cells and a relatively high proportion (39%) of these contained IgM. The case of atypical measles encephalitis differed from those of SSPE also in the presence of multinucleate giant cells, some of which contained measles virus antigen.

Three-dimensional architecture of identified cerebral neurosecretory cells in an insect.

The organization of identified neurosecretory cell groups in the larval brain of the tobacco hornworm, Manduca sexta, was investigated immunocytologically. Computer-assisted three-dimensional reconstruction was used to examine the architecture of the neurosecretory cell groups. The group III lateral neurosecretory cells (L-NSC-III) which produce the prothoracicotropic hormone are located dorsolaterally in the protocerebrum and extend axons medially that decussate to the contralateral lobe prior to exiting the brain through the nervi corporis cardiaci I + II. The group IIa2 medial neurosecretory cells (M-NSC IIa2) are located anteriorly in the medial dorsal protocerebrum. The axons of these cells also exit the brain via the contralateral nervi corporis cardiaci I + II. However, their axons traverse a different pathway through the brain from that of the L-NSC III axons. Each of the cell groups possesses elaborate dendrites with terminal varicosities. The dendrites can be classified into specific fields based upon their location and projection pattern within the brain. The dendrites for these two neurosecretory cell groups overlap in specific regions of the protocerebral neuropil. After the axons of these neurosecretory cells exit the brain through the retrocerebral nerve, they innervate the corpus allatum where they arborize to form neurohemal terminals in strikingly different patterns. The L-NSC III penetrate throughout the glandular structure and the M-NSC IIa2 terminals are restricted to the external sheath. A third group of cerebral neurosecretory cells, the ventromedial neurons (VM) which stain with the monoclonal antibody to prothoracicotropic hormone in Manduca, are located anteriorly in the medial region of the brain. The axons of these cells do not exit the brain to the retrocerebral complex, but rather pass through the circumesophageal connectives and ventral nerve cord. These neurons appear to be the same VM neurons that produce eclosion hormone. One dendritic field of the L-NSC III terminates in close apposition to the VM neurons. The distinct morphologies of these neurosecretory cell groups in relation to other cell groups and the distribution of neuropeptides within the neurons suggest that insect neurosecretory cells, like their vertebrate counterparts, may have multiple regulatory roles.

Gliadin antibody detection in gluten enteropathy.

Circulating antigliadin antibody has been described in patients with gluten enteropathy although the prevalence varies in different studies. It has been suggested that the investigation for antigliadin antibody might be useful as a screening test. The object of the present study was to evaluate two different techniques for assaying these antibodies - an indirect immunofluorescent method and an enzyme-linked immunosorbent assay (ELISA). Antibodies were assayed in the sera of 102 patients in whom jejunal biopsies were also obtained. The specificity of both tests was greater than 95%, and the correlation between the presence of antibody and histology was significant (p < 0.005), though the sensitivity of each test was less than 70%.

Clinical and laboratory characteristics of patients with speckled pattern antinuclear antibodies.

Fifty patients whose sera contained a speckled antinuclear antibody (ANA) were interviewed and examined to determine if there was any relationship between their clinical manifestations and the presence of certain serological markers. The results suggest that speckled ANA is usually found in patients with definite connective tissue diseases, but a significant minority have incomplete or early stages of these diseases. Characterisation of the antibody to extractable nuclear antigen (ENA) and other serological markers does not normally assist in making a clinical diagnosis, but the detection of a speckled ANA should prompt further investigation and careful follow-up.