PubMed Health⌕ Search

Biomedical subjects

F Guscetti

Publications and source records attributed to F Guscetti.

At least 19 recordsLinked to original sources

Synaptophysin: an immunohistochemical marker for animal dysautonomias.

Equine and feline dysautonomias are characterized histopathologically by degenerating neurons with chromatolysis, pyknotic and sometimes eccentric nuclei, and loss of Nissl substance in the peripheral autonomic ganglia. Because it may be difficult to distinguish pathological from post-mortem changes in affected ganglia by histopathological examination, synaptophysin was evaluated as an immunohistochemical marker. Degenerating neurons showed strong intracytoplasmic labelling indicating abnormal accumulation of synaptophysin. It was concluded that synaptophysin immunohistochemistry is a helpful tool for detecting degenerating neurons in equine (grass sickness) and feline (Key-Gaskell syndrome) dysautonomias.

Animals↗

Overt fatal and chronic subclinical Encephalitozoon cuniculi microsporidiosis in a colony of captive emperor tamarins (Saguinus imperator).

The course of an infection with the microsporidian Encephalitozoon cuniculi in a colony of captive emperor tamarins (Saguinus imperator) is described. In two litters, the infection was associated with overt disease and death of all infants. Immunohistochemistry for E. cuniculi showed generalized infections, and histopathologic evaluation revealed systemic vasculitis and disseminated mixed inflammatory cell infiltration with and without necrosis in several organs. Serologically, some of the juvenile animals presented with high titres for Encephalitozoon, while the adults had low titres. The E. cuniculi "dog strain" was identified by molecular means for the first time in Europe. The origin of the infection appeared to be a pair of breeding adults that originated from the US. Our data suggest that the organism persisted over years in the colony, and that subclinically infected animals most likely were involved in perpetuating the infection. Efforts should be made to ascertain if this microorganism is present in other captive populations of this endangered monkey species and to prevent its further spreading.

Animals↗

Ocular manifestation of disseminated Mycobacterium simiae infection in a cat.

Disseminated mycobacterial disease was diagnosed in an eight-year-old domestic shorthaired cat, with involvement of the skin, lungs, lymph nodes and one eye. Mycobacterium simiae was cultured from skin biopsies on solid agar and in liquid media. This organism is known to cause pulmonary, cutaneous or disseminated infection in human patients with acquired immunodeficiency syndrome but has never been encountered as a pathogen in companion animals. Combination treatment with rifampicin, enrofloxacin and clarithromycin resulted in complete clinical remission within six months, with no side effects. No recurrence was observed in a 22-month follow-up period.

Animals↗

Experimental infection of pregnant ewes with enteric and abortion-source Chlamydophila abortus.

Two groups of pregnant ewes were experimentally infected oronasally in midpregnancy. A faecal and an abortion-source isolate of Chlamydophila abortus were used. They were derived from a healthy ewe from a flock with no history of abortion, and from an aborted foetus in a farm with enzootic abortion. As assessed by modified Ziehl-Neelsen (MZN) staining, egg culture, antigen ELISA, the Clearview test and immunohistochemistry, inoculation resulted in placental and/or foetal infection in all ewes. Histopathology revealed placentitis in two and four ewes inoculated with the enteric or abortion-source isolate, respectively, in addition, these samples were immunohistochemically positive for chlamydial antigen. All six ewes infected with the enteric isolate and five of seven ewes infected with the abortion-source isolate showed evidence for a serological response by an indirect ELISA or CFT. Neither chlamydiae nor lesions were detected in the placentae and lambs of the uninfected control ewes, which remained seronegative. Our results suggest that enteric C. abortus can be associated with placental and foetal lesions in sheep.

Abortion, Veterinary↗

Primary ciliary dyskinesia with situs inversus totalis, hydrocephalus internus and cardiac malformations in a dog.

A nine-month-old golden retriever bitch was presented with exercise intolerance and recurrent nasal discharge. Based on clinical, radiographic and ultrasonographic examination, a diagnosis of rhinitis, situs inversus totalis and tricuspid valve insufficiency was established. The results of video- and electron microscopy studies of the respiratory epithelium were compatible with primary ciliary dyskinesia (PCD). However, no evidence of a primary ultrastructural defect of the cilia was found. The dog was euthanased because of the poor prognosis. At necropsy, a hydrocephalus internus and a subaortic stenosis were additionally diagnosed. PCD, in combination with situs inversus, has been previously reported in golden retrievers, but without a concomitant hydrocephalus internus. Furthermore, concomitant occurrence of internal cardiac malformation and PCD has not previously been reported in the dog.

Animals↗

Identification of focal adenomyosis as a uterine lesion in two dogs.

A focal uterine adenomyosis is described in two bitches. In both cases, the uterus showed knobbly enlargements of 4 to 8 cm in diameter, which resulted in distinct clinical symptoms. Other pathological changes of the uterus were not present. One bitch was presented because of a history of vaginal discharge of several months' duration. Radiographs, as well as ultrasonography, revealed a soft tissue lesion at the cervix. The other bitch showed a marked reduction in its general condition and a sudden onset of a tense abdomen. Radiologically, a lesion of soft tissue opacity was observed in the mid-abdomen and was seen to originate from the left uterine horn during exploratory laparotomy. A torsion of the lesion was present, which explained the clinical signs in this second case.

Animals↗

Experimental enteric infection of gnotobiotic piglets with a Chlamydia psittaci strain of avian origin.

The pathogenicity of a Chlamydia psittaci isolate of pigeon origin was assessed using a litter of gnotobiotic piglets. At 3 days of age, six piglets were inoculated intragastrically with egg-grown chlamydiae, the remaining six pigs were sham-inoculated. The animals were observed for clinical signs, and they were killed and necropsied sequentially between 4 and 15 days of age. Clinical manifestations consisted of slight softening of the faeces between 6 and 10 days post-inoculation (DPI). Immunohistochemistry revealed chlamydial replication predominantly in the small intestine, initially within villous enterocytes, after 4 DPI mostly in the lamina propria. Histopathology showed villous atrophy and increased numbers of inflammatory cells in the gut up to 6 DPI. Chlamydial stages of normal morphology were identified within enterocytes using transmission electron microscopy. An enzyme-linked immunosorbent assay (ELISA) run on faecal samples revealed shedding of chlamydial antigen from 3 until 11 DPI. Systemic dissemination of Chlamydia occurred to a limited extent according to polymerase chain reaction and immunohistochemistry results of several extraintestinal organs. Corresponding histopathological changes were minimal. Sera of all pigs were negative for anti-chlamydial antibodies using a complement fixation test. In conclusion, inoculation of this isolate in gnotobiotic piglets resulted in a productive enteric infection with mild lesions, weak systemic dissemination, and faecal shedding, indicating the pig as a potential host for avian chlamydiae.

Animals↗

Feline infectious pneumonia: a short literature review and a retrospective immunohistological study on the involvement of Chlamydia spp. and distemper virus.

A short literature review of feline infectious pneumonia, feline Chlamydia and Paramyxoviridae is presented. In a retrospective study (from 1987 to 1996) 245 cases of feline pneumonia or conjunctivitis/rhinitis were investigated: histological diagnoses and aetiologies were compared; all lungs were examined immunohistologically for the occurrence of chlamydia and of canine distemper virus (CDV), but neither pathogen could be demonstrated. The results confirm previous reports indicating that feline chlamydia is not a primarily pulmonary pathogen and that CDV is not a causative agent of pneumonia in cats as it is in large felids. The review provides a summary of the known causes and pathology of infectious pneumonia in cats (in order of frequency), although some remain aetiologically uncertain. It focuses on chlamydia and distemper virus - a recognized and as yet unknown cause of feline pneumonia. The role and especially the frequency of chlamydia as a cause of feline pneumonia are controversial but distemper virus, known to cause pneumonia in dogs and large felids, has not as yet been demonstrated in cats. The aims of the retrospective study were to determine the occurrence of chlamydia in 245 cases of feline pneumonia or conjunctivitis/rhinitis, and to investigate the presence of CDV in these lungs.

Animals↗

Evidence for a parasite-mediated inhibition of abomasal acid secretion in sheep infected with Ostertagia leptospicularis.

The acid secretory capacity of the abomasal mucosa was studied in sheep experimentally infected with Ostertagia leptospicularis. The acidity of the abomasal contents, permanently recorded by a pH probe located inside the abomasum, decreased markedly to mean levels between pH 5 and 6. Subcutaneous administration of histamine or carbachol successfully stimulated acid secretion (pH 3.4). The results indicate that the abomasal mucosa harboured a population of functional parietal cells which were also identified immunohistochemically (H(+)/K(+)-ATPase). Ultrastructural investigation before stimulation revealed that the majority of these cells was in a resting state. Despite high serum gastrin levels, the acid secretion was blocked either at the level of the parietal cell or the enterochromaffin-like cell by an unknown factor, possibly mediated by the parasites. This is the first report of a parietal cell dysfunction associated with a nematode infection in the abomasum. It is suggested that the parasites induce changes in their environment which favour their survival and/or increase their reproduction.

Abomasum↗

No association of Chlamydia with abortion.

Case reports and serological work have raised the possibility that chlamydias can infect the placenta and thus harm the fetus. We investigated the involvement of Chlamydia in a series of 195 unselected cases of spontaneous abortion or miscarriage. Formalin-fixed placental tissues from all cases were examined immunohistochemically, for the presence of chlamydial lipopolysaccharide, as well as histopathologically. A serum sample was collected from 187 of the patients for detection of anti-chlamydial antibodies by microimmunofluorescence. All placental sections were negative for chlamydial antigen. Serological findings indicated that 8 patients had been in contact with C. trachomatis, 15 patients with C. pneumoniae, and none with C. psittaci. A few cases of perivillitis or intervillitis were detected, but none exhibited the intracytoplasmic inclusions typical of C. psittaci. Although these results are negative a search for Chlamydia in abortion materials should be encouraged.

Abortion, Spontaneous↗

Experimental Chlamydia psittaci serotype 1 enteric infection in gnotobiotic piglets: histopathological, immunohistochemical and microbiological findings.

The enteric pathogenicity of the ovine C. psittaci serotype 1 isolate S26/3 was assessed using a litter of gnotobiotic piglets. In one group, eight piglets were inoculated at 3 days of age; at 10 days, two of these were re-inoculated. In a second group, six animals were mock-inoculated at 3 days of age as negative controls; subsequently, at 10 days, three of these piglets were inoculated with C. psittaci. The animals were observed for clinical signs, killed and necropsied sequentially between 4 and 17 days of age. At necropsy, specimens were collected for histopathology, immunohistochemistry and serology. Clinical manifestations consisted of sporadic slight softening of faeces observed between 8 and 12 days post inoculation (d.p.i.) in pigs inoculated at 3 days of age and between 4 and 6 d.p.i. in those inoculated at day 10. Histopathological changes were minimal and inconsistent and occurred almost exclusively in the small intestine in pigs of 15 days of age and older; they consisted of a slight shortening of villi, of a small number of tongue-shaped villi and of villous fusions. Immunohistochemistry revealed small numbers of chlamydial inclusions in the small intestinal enterocytes of only five pigs, all killed within 5 d.p.i. An ELISA run on faecal samples collected daily after inoculation from six of the pigs showed that chlamydial antigen was excreted in the faeces. In pigs inoculated at 3 days, chlamydial antigen was detected inconsistently before, and consistently after 9 d.p.i. Pigs inoculated at 10 days excreted antigen consistently after inoculation until the end of their observation period (8 d.p.i.). Infective chlamydiae were detected from the faeces of inoculated piglets using Vero cell cultures. Sera of all pigs were negative for anti-chlamydial antibodies using a complement fixation test. In conclusion, enteric pathogenicity of C. psittaci serotype 1 in a litter of gnotobiotic piglets proved minimal. The results, therefore, indicate that serotype 1 C. psittaci is not likely to cause enteric disease in conventionally reared pigs. Nevertheless, a potential role of swine in the epidemiology of this agent should be considered with regard to spread of Chlamydia to other species.

Animals↗

Immunohistochemical detection of porcine epidemic diarrhea virus compared to other methods.

An immunohistochemistry method using formalin-fixed tissues, a direct immunofluorescence method using cryostat sections, an enzyme-linked immunosorbent assay (ELISA), and a PCR method were compared for diagnosis in a litter of weaned pigs that had been experimentally inoculated with wild-type porcine epidemic diarrhea virus (PEDV) and killed between 6 and 60 h after onset of diarrhea. The immunohistochemistry method proved to be as reliable as direct immunofluorescence for diagnosis of PEDV in tissues collected postmortem. The good reliability of ELISA for investigating clinical samples was confirmed, whereas the PCR method used was ineffective.

Animals↗

Ultrasonographic examination of the abomasum of 50 cows.

The purpose of this study was to determine the position, appearance and dimensions of the abomasum of 50 healthy cows by ultrasonography. The ventral abdominal region caudal to the xiphoid process was examined with a 3.5 MHz linear transducer. The abomasum could be visualised from both sides and from the ventral midline of 47 of the cows. The abomasum could be clearly differentiated from adjacent organs because of its contents, which appeared as a heterogeneous, moderately echogenic structure with echogenic stippling. However, the wall of the abomasum appeared, if at all, as a narrow echogenic line. Parts of the abomasal folds were visible occasionally as echogenic structures within the abomasum. Slow movement of the feed in the abomasum was also often visualised. The pylorus was positively identified in only one cow. The cranial margin of the abomasum was situated up to 15 cm caudal to the xiphoid process. The abomasum was between 7.4 and 42.9 cm long, and its maximal extent, measured from the ventral midline to the left, was from 5.0 to 26.0 cm in the cranial region and from 5.0 to 16.0 cm in the caudal region. From the ventral midline to the right, it was from 5.0 to 33.0 cm in the cranial region and from 28.0 to 36.0 cm in the caudal region. The minimal dorsoventral dimension of the abomasum ranged from 0.7 to 7.2 cm, and its maximal dorsoventral dimension ranged from 3.6 to 11.1 cm.

Abomasum↗

Chlamydiae in porcine abortion.

Formalin-fixed, paraffin-embedded fetal livers and lungs from 139 cases of swine abortion were investigated retrospectively for chlamydiae by means of immunohistochemistry. Using a genus-specific antibody, chlamydial antigen was found in eight livers obtained from five (3.6%) abortion cases from different herds. All lung sections were negative. Chlamydiae were also labeled in five of the eight positive livers using a monoclonal antibody against immunotype 1 of Chlamydia psittaci; the remaining three livers were negative. No reactivity was seen using an antibody specific for C. trachomatis. Chlamydiae should be considered a cause of abortion in sows in Switzerland. Porcine abortigenic strains identified in this study differed immunologically from intestinal strains (known to be mainly C. trachomatis) but shared similarities with abortigenic chlamydiae of ruminants.

Abortion, Septic↗

Intestinal Chlamydia in finishing pigs.

Gut and blood samples from 119 finishing pigs derived from 11 farms were collected during routine slaughter at an abattoir. Sections of formalin-fixed, paraffin-embedded tissues were labeled immunohistochemically using genus-specific, mouse monoclonal antibody against chlamydial lipopolysaccharide; goat polyclonal antiserum against the major outer membrane protein of Chlamydia trachomatis; and mouse monoclonal antibody against the ovine abortion subtype of C. psittaci. Gut samples from 33 of 111 (29.7%) individual pigs stained positive with the genus-specific monoclonal antibody, and of these 30 of 32 (93.7%) also reacted with the C. trachomatis-specific antiserum. Labeled inclusions were restricted to mature enterocytes of the large intestine in 33 of 111 cases. Infection of small intestinal enterocytes was noted in only one of 82 ileal samples. The blood samples were tested for antichlamydial antibodies by enzyme-linked immunosorbent assay (ELISA) and complement fixation test (CFT). With ELISA, 95 of the 115 sera tested (82.6%) yielded positive antichlamydial reactions. With CFT, 34 of the 119 sera tested (28.6%) were unequivocally positive (> or = 1:10, 100% binding), and 10 (7.6%) yielded doubtful positive reactions (1:10, 50-75% binding). Positive ELISA and CFT titers showed poor agreement (kappa = 0.112), whereas the agreement between positive findings by immunohistochemical labeling and CFT was fair (kappa = 0.205).

Animals↗

[Endoparasite infection in stray and abandoned dogs in southern Switzerland].

At their entry into the animal domicile, "La Stampa", in Lugano (canton Tessin), 217 stray dogs and 154 unwanted dogs were examined for infections with intestinal parasites, filariae, Babesia and Leishmania. The following techniques were used for detection of intestinal parasites: combined sedimentation-flotation, MIFC technique and scotch tape adherence test. Prevalences of helminth egg excretion in stray dogs and in unwanted dogs, respectively, were as follows: 34% and 22% for Trichuris, 17% and 14% for Toxocara, 3% and 5% for hookworms, 4% and 0% for taeniids. Dipylidium, Toxascaris and Capillaria were diagnosed sporadically. Samples positive for taeniids were further tested for the presence of Echinococcus coproantigens in a sandwich ELISA: one of 9 dogs was strongly positive. This dog was euthanized for security reasons and upon dissection, 11 Taenia hydatigena and more than 10,000 gravid Echinococcus granulosus worms were found. Microfilariae were detected in the blood of 3 stray dogs and one unwanted dog by the Difil-test. In all 4 cases the infective species was Dirofilaria immitis as confirmed by morphology, acid phosphatase activity analysis of microfilariae and by detection of specific antigens in blood plasma by ELISA. Specific antibodies against antigen of Leishmania infantum could not be detected in any of these dogs by ELISA. However, 3 stray dogs had specific antibodies against antigen of Babesia canis as demonstrated by IFAT.

Animals↗

[Neoplasms originating from large granular lymphocytes in a dog and cats].

Clinical, cytological and pathological findings in three cases of large granular lymphoma in a dog and two cats are presented. These tumors consist of large granular lymphocytes, which have been in part classified as natural killer cells, based on their phenotype and functional aspects. It is likely that such tumors are more frequent than commonly appreciated, because they are only recognized as such in cytological preparations or in electron microscopy.

Animals↗