Biomedical subjects

K R Mittal

Publications and source records attributed to K R Mittal.

At least 55 records · Page 3Linked to original sources

PubMed1993

Contralateral ovary in unilateral ovarian carcinoma: a search for preneoplastic lesions.

Contralateral ovaries from patients with unilateral ovarian carcinoma were examined and compared to ovaries from age-matched control patients without ovarian carcinoma. The number of inclusion cysts were increased in ovaries from patients with ovarian carcinoma compared to the controls (p < 0.01). In addition, inclusions from cases with ovarian carcinoma showed serous differentiation more frequently than the controls (p < 0.01; odds ratio = 10.0; 95% confidence interval = 1.2-78.1). An age-related increase in the number of inclusion cysts was seen in the study group but not in the control group. These findings support a role of surface inclusion cysts in the genesis of ovarian carcinoma.

Adult↗

PubMed1993

Flow cytometric DNA ploidy and quantitative histopathology in partial moles.

This study quantitates morphologic changes seen in partial moles and hydropic abortuses in an attempt to find a correlation with DNA content. Thirty-two products of conception were studied. Fifteen were diagnosed as definitive partial moles (DPM), and 17 had changes suggestive of a partial mole (SPM). We determined DNA ploidy by flow cytometry and quantitatively analyzed the following microscopic features: villous edema and sclerosis, central cistern formation, villous blood vessels, trophoblastic proliferation, and trophoblastic inclusions. No single pathologic feature significantly correlated with DNA content, even though triploid cases showed more inclusions than diploid cases (8.3 versus 7.2 on the average per ten x 100 fields). An overall diagnosis of DPM did correlate with ploidy; 12 of 18 triploid cases (67%) compared with only three of 13 diploid cases (23%) had been previously diagnosed as DPM (p < 0.05). Flow cytometric DNA ploidy estimates DNA content and cannot determine chromosomal origin. It is possible that detailed cytogenetic studies of moles compared with abortuses may show a significant correlation of the proportion of paternal chromosomes, morphologic changes, and the risk of persistent gestational trophoblastic disease.

Abortion, Incomplete↗

PubMed1993

Comparison of isolation methods for the recovery of Bordetella bronchiseptica and Pasteurella multocida from the nasal cavities of piglets.

Nasal swabs from 241 piglets from 12 herds with clinical atrophic rhinitis and 283 piglets from 14 herds without clinical atrophic rhinitis were examined for the presence of Bordetella bronchiseptica and/or Pasteurella multocida. For B. bronchiseptica, swabs were streaked on three selective media. Blood agar supplemented with cephalexin was the most satisfactory selective culture medium for the isolation of B. bronchiseptica. For P. multocida, swabs were also streaked on three selective media. Mice were also used for isolation of P. multocida from the nasal cavities of pigs. The mouse inoculation test was not found to be the definitive test for the isolation of P. multocida. A significant number of P. multocida strains were avirulent in the mouse model. The modified Knight medium (without potassium tellurite) was the best single method for isolating P. multocida. However, a combination of mouse passage and direct culture on selective media increased the rate of isolation. There was no marked difference in the prevalence of B. bronchiseptica or P. multocida in swine herds with or without clinical atrophic rhinitis. Both capsular types A and D were present in the nasal cavities of the pigs with or without clinical atrophic rhinitis.

Animals↗

PubMed1993

Evaluation of counterimmunoelectrophoresis for serotyping Actinobacillus pleuropneumoniae isolates and detection of type-specific antigens in lungs of infected pigs.

A rapid, simple, and accurate counterimmunoelectrophoresis technique was developed for serotyping cultures of Actinobacillus pleuropneumoniae as well as for detection of their type-specific antigens in the lung tissues of infected pigs. The counterimmunoelectrophoresis test correctly identified all of the reference antigens and more than 99% of 1,200 field isolates of A. pleuropneumoniae representing the 12 established serotypes within 1 h. Counterimmunoelectrophoresis and coagglutination tests did not differ broadly in sensitivity from each other. Both procedures were more rapid and more sensitive than immunodiffusion and indirect hemagglutination tests. A total of 355 lung tissue samples (130 lungs of pigs that died because of acute respiratory problems, 125 lungs of pigs from herds with chronically infected pleuropneumonia, and 100 lungs from apparently healthy pigs at the slaughterhouse) were examined for the presence of A. pleuropneumoniae type-specific antigens by counterimmunoelectrophoresis, coagglutination, and immunodiffusion tests. A. pleuropneumoniae type-specific antigen was found in all 55 samples from which the bacteria had earlier been isolated and in 27 specimens in which they had not been found. Detection of antigen in the lung tissues by coagglutination and counterimmunoelectrophoresis tests was found to be much simpler and much more rapid than conventional culture isolation. Both counterimmunoelectrophoresis and coagglutination tests were found extremely useful in the diagnosis of acute cases of porcine pleuropneumonia. However, these techniques were able to detect only some of the chronically infected carrier pigs.

Actinobacillus Infections↗

PubMed1993

Squamous cell carcinoma in HIV-positive patients under age 45.

Eight patients 45 years of age and under (range, 29 to 45) with squamous cell carcinoma of the head and neck and infection with the human immunodeficiency virus are reported. Primary tumor sites include nasopharynx, oral cavity, oropharynx, and larynx. Probes for the human papillomavirus were positive in two of the patients. Therapy consisted of surgery followed by radiation therapy in five patients, surgery alone in one patient, and radiation therapy in the remaining two patients. Follow-up ranged up to 2 years and revealed four deaths, three patients alive without disease, and one patient recently posttreatment with residual disease. The significance of the presence of the human papillomavirus in these individuals remains to be determined. The incidence of squamous cell carcinoma of the head and neck under age 45 is low, and whether there may be a higher incidence in HIV-positive patients cannot be determined from this small series.

Adult↗

PubMed1993

Detection of Actinobacillus pleuropneumoniae in the porcine upper respiratory tract as a complement to serological tests.

Attempts were made to isolate Actinobacillus pleuropneumoniae from the nasal cavities and tonsils of 442 healthy pigs from 15 herds. Samples were streaked onto different media formulations. Serum samples were assayed for antibodies to A. pleuropneumoniae by enzyme-linked immunosorbent assay and complement fixation test. Actinobacillus pleuropneumoniae was isolated from the nasal cavities only in 24 pigs, from tonsils only in 90 pigs, and from both the nasal cavities and the tonsils in 11 pigs. A PPLO medium supplemented with lincomycin, bacitracin and crystal violet allowed recovery of A. pleuropneumoniae from more animals than a tryptic soy agar medium from both sites. Incubation of plates in an enriched CO2 atmosphere did not affect the recovery rate. Actinobacillus pleuropneumoniae belonging to serotypes 1, 2, 3, 5a, 5b, 7, 8, 10 and 12 were isolated, and, in several herds, more than one serotype were recovered. Serotypes of A. pleuropneumoniae were isolated from nine herds which were found seronegative to these. The isolation of A. pleuropneumoniae from the upper respiratory tract can be useful for detection of carrier pigs and complements serological screening.

Actinobacillus Infections↗

PubMed1993

Rapid development of lymphoma following liver transplantation in a recipient with hepatitis B and primary hemochromatosis.

We report a case of a posttransplant lymphoproliferative disorder (PTLD) which presented in a liver allograft shortly after transplantation. The patient, who had been transplanted because of cirrhosis due to primary hemochromatosis and chronic hepatitis B infection (HBV), developed early recurrent HBV in the graft, and 2 months after transplantation, liver biopsies showed a malignant large-cell lymphoma. The neoplastic cells demonstrated Epstein-Barr virus DNA by in situ hybridization. The patient died 3.5 months posttransplant due to liver failure. At autopsy, the liver showed nodules of malignant lymphoma, massive hepatic necrosis, and iron overload, but no evidence of rejection. This report suggests that the grafted liver can be the site of PTLD in recurrent HBV and hemochromatosis.

Adult↗

PubMed1992

Lymphoma of ovary with stromal luteinization, presenting as secondary amenorrhea.

A case of primary lymphoma of the ovary with extensive stromal luteinization is presented. Immunohistochemical markers that work satisfactorily in fixed tissues allowed a diagnosis of B cell lymphoma to be made on formalin-fixed tissue sections. Immunohistochemical analysis of frozen tissue and genotypic analysis confirmed the diagnosis of B cell lymphoma. By electron microscopy two populations of cells, including large atypical lymphoid cells and luteinized stromal cells, were identified. Presentation with amenorrhea and resumption of menstrual periods after removal of the tumor suggested the possibility of functional activity in the luteinized stromal cells. Stromal luteinization has not been previously described in primary ovarian lymphoma.

Adult↗

PubMed1992

Serological characterization of Actinobacillus pleuropneumoniae strains isolated from pigs in Quebec.

A total of 3306 isolates of A. pleuropneumoniae originating from lung tissues of pigs that died of acute pleuropneumonia and 140 isolates recovered from tonsils or nasal cavities of apparently healthy pigs from chronically infected herds were serotyped. Various serotyping methods, such as slide agglutination, tube agglutination, ring precipitation, coagglutination, immunodiffusion, indirect hemagglutination and counterimmunoelectrophoresis either alone or in combination were used. The techniques used for serotyping continued to evolve during the last 10 years depending on the problem encountered in serotyping. Antisera prepared in rabbits against formalinized whole cell suspensions of reference strains of A. pleuropneumoniae of serotypes 1 to 12 were employed for serotyping. Serotype 1 was predominant ranging from 55 to 87% from year to year during the last 10 years with an average prevalence of 68%. Serotype 5 was second in prevalence ranging from 9 to 30% with a mean of 23%. Both subtypes of serotype 5 (5a and 5b) were present in Quebec. Serotypes 3, 6, 7, 8, 10 and 12 were isolated in small numbers together accounting for about 9%. Serotypes 4, 9 and 11 were not present. Cross-reactions were observed among isolates of serotypes 3, 6 and 8, and 1, 9 and 11 and were easily differentiated from each other by quantitation of type and group specific antigens by coagglutination and immunodiffusion tests. Serotypes 1, 5 and 7 were isolated most frequently from tonsils of pigs from chronically infected herds. Prevalence of different serotypes in different countries has also been reviewed.

Actinobacillus Infections↗

PubMed1992

Patterns of keratin 19 expression in normal, metaplastic, condylomatous, atrophic, dysplastic, and malignant cervical squamous epithelium.

Keratin 19 (K-19) expression has been strongly correlated with dysplasia in oral epithelium. Expression of K-19 was evaluated by immunoperoxidase staining in formalin-fixed normal ectocervical tissue, normal endocervical tissue, cervical dysplasia, squamous metaplasia, atrophic epithelium, cervical condylomas, and invasive carcinoma to determine if a correlation of K-19 expression with dysplasia was present in the cervical epithelium. Uniform expression of K-19 was seen in endocervical epithelium and in the basal layer of normal ectocervical epithelium in all areas where these epithelia were present. Cervical dysplasia without associated condylomatous changes showed increased expression of K-19 in suprabasal epithelium, corresponding to the level of immature cells. Squamous metaplasia was characterized by scattered cells with increased staining (patch-quilt pattern). There was considerable overlap in the patterns of K-19 expression in dysplastic and metaplastic epithelium. Thus K-19 staining pattern could not be used as a distinctive marker for dysplasia in the cervical epithelium. Atrophic epithelium showed a characteristic uniform but low-level expression of K-19 in suprabasal areas. This pattern may be of diagnostic use in differentiating atrophic lesions from dysplasia. Condylomas showed focal loss of K-19 in the basal layer, suggesting induction of premature differentiation in the basal layer by human papillomavirus infection. Invasive carcinomas showed variable patterns. K-19 is a marker of immature cervical squamous epithelium, with generally distinctive but sometimes overlapping patterns of expression in various diagnostic categories.

Atrophy↗

PubMed1992

Superficial nuclear enlargement without koilocytosis as an expression of human papillomavirus infection of the uterine cervix: an in situ hybridization study.

Nuclear enlargement of the superficial cervical epithelial cells in the absence of koilocytosis is frequently observed. The purpose of this study was to investigate whether this change represents human papillomavirus (HPV) infection. We reviewed 257 cervical biopsies with the diagnosis of "suggestive of condyloma," mild or moderate dysplasia, or both. Of the 257 consecutive biopsies, 23 fulfilled the two criteria: the superficial cells had a nuclear diameter of at least twice that of the basal nuclei, and complete absence of koilocytosis was seen. Parallel sections from each paraffin block were hybridized with biotinylated probes for HPV 6/11, 16/18, and 31/35/51 under high-stringency conditions. The cases that were negative at high-stringency conditions were then hybridized under low-stringency conditions with a mixture of the three HPV probes. Twelve of the 23 cases (52.17%) were positive for HPV, including one positive for HPV 16/18 in one area and for HPV 31/35/51 in another area, four positive for HPV 31/35/51, two positive for HPV 16/18, two positive for HPV 6/11, and three positive for HPV probe mixture at low-stringency conditions. The positive in situ hybridization was located predominantly in the enlarged nuclei in the superficial layers. In conclusion, HPV infection can be expressed as nuclear enlargement in the superficial layers of the cervical epithelium in the absence of koilocytosis.

Cell Nucleus↗

PubMed1992

Characterization of Pasteurella multocida from nasal cavities of piglets from farms with or without atrophic rhinitis.

A total of 137 strains of Pasteurella multocida isolated from the nasal tracts of pigs with and without clinical atrophic rhinitis (AR) were studied for their biochemical, antigenic, and toxigenic characteristics. There were no major biochemical differences among the P. multocida isolates. Capsular antigen types A and D were both present in the nasal cavities of the pigs with or without clinical AR. However, the prevalence of type D was higher on farms with pigs with AR. Types A and D with different somatic antigens could both be present in the same pig. There was no correlation between somatic types and/or capsular types with the clinical AR status of the pigs on the farm. Toxigenic isolates were found only in pigs which had a problem of clinical AR, and a great majority of these isolates belonged to type D. Since there was a high level of heterogeneity of the strains in the P. multocida population on a farm, several strains should be characterized before the diagnosis of AR could be excluded on the basis of the absence of isolation of rhinopathogenic P. multocida strains.

Animals↗

PubMed1991

Cloacogenic carcinoma of the anal canal and associated viral lesions. An in situ hybridization study for human papilloma virus.

Five cases of cloacogenic carcinoma were analyzed for microscopic human papilloma virus (HPV)-induced changes and with in situ hybridization technique for HPV types 6/11, 16/18 and 31/35/51. Four of the five cases showed epithelial foci of koilocytotic atypia. HPV type 16/18 was present in four of the five cases. The surface epithelium in two of the four cases with koilocytotic changes showed HPV type 16/18. HPV type 6/11 was seen in surface epithelium in one case in which invasive carcinoma showed HPV type 16/18. This double infection with double morphologic expression could mean that the same behavioral pattern (anal intercourse) may contribute to both anal condyloma and carcinoma and, although patients with condyloma are at risk for carcinoma, condyloma may not be the precursor lesion in all cases with coexistent condyloma and carcinoma. Because of the similarity between pathogenesis of anal and cervical carcinomas, a periodic cytologic screening of anal mucosa could be indicated in populations at risk: homosexual men, patients with condyloma, women having dysplasia or carcinoma of the uterine cervix, and patients with immunosuppressive disorders.

Aged↗

PubMed1991

Factors involved in immunity against Actinobacillus pleuropneumoniae in mice.

Active and passive immunization studies in mice were undertaken to examine the protective efficiency of vaccines prepared from different components of Actinobacillus pleuropneumoniae, or combinations thereof. Subcutaneous immunization using either washed formalinized whole cells, capsular polysaccharide, lipopolysaccharide or purified hemolysin I (105 kDa protein) partially protected mice against intranasal challenge with a lethal dose of homologous or heterologous A. pleuropneumoniae serotypes. However, full protection was obtained if the formalinized whole cells were supplemented with purified hemolysin. Similar protection was obtained when mice were immunized simultaneously with a sublethal dose of live cells by the intranasal route and with formalinized whole cells subcutaneously. Passive immunization using rabbit hyperimmune serum against formalinized whole cells provided almost total protection whereas hyperimmune serum against capsular polysaccharide, lipopolysaccharide or hemolysin alone provided only a partial protection. Cell mediated immunity as detected by the foot pad test may not be implicated significantly in the protein against acute A. pleuropneumoniae infection. However, humoral immune response seems to play an important role in protection. All the antigenic components examined may contribute to the protection to some extent. However, heat-labile components such as hemolysin and outer membrane proteins may play a crucial role in protection against acute challenge infection.

Actinobacillus Infections↗

PubMed1991

Biochemical and serological characterization of Campylobacter cryaerophila.

Sixty-two isolates of Campylobacter cryaerophila were recovered from aborted porcine and bovine fetuses, from porcine, bovine, and equine feces, and from different tissues of a dead piglet. Phenotypic characterization was carried out on all isolates, and the results were compared with those obtained with the reference strains of C. cryaerophila, C. jejuni, C. coli, C. laridis, and C. hyointestinalis. The ability of C. cryaerophila strains to grow under aerobic conditions at 16 degrees C was found to be most useful in differentiating them from strains of other Campylobacter species. Studies were undertaken to develop a serotyping system for C. cryaerophila on the basis of the Lior serotyping system for C. jejuni and C. coli by use of a tube agglutination test with formalinized whole-cell (FWC) and boiled whole-cell (BWC) antigens. Antisera against 18 strains of C. cryaerophila were produced in rabbits. Thirty-five percent of C. cryaerophila strains were typed with the FWC suspension as an antigen, and 61% were typed with the BWC suspension as an antigen. None of the C. cryaerophila strains tested autoagglutinated in saline. BWC antigens of C. jejuni, C. coli, and C. laridis cross-reacted with C. cryaerophila, whereas FWC antigens did not cross-react. Neither FWC nor BWC antigens of C. hyointestinalis reacted with C. cryaerophila antisera.

Agglutinins↗

PubMed1991

Cross-reactivity and antigenic heterogeneity among Actinobacillus pleuropneumoniae strains of serotypes 4 and 7.

Actinobacillus pleuropneumoniae strains of serotypes 4 and 7 were studied for their antigenic properties by means of agglutination, coagglutination, indirect hemagglutination, immunodiffusion, and counterimmunoelectrophoresis tests. Strains of serotype 4 showed cross-reactivity with those of serotype 7 in various serological tests. Serotype 7 strains were antigenically heterogeneous and shared common antigens with several other serotypes. By using boiled whole-cell saline extract as the antigen in the immunodiffusion test, serotype 7 strains could be divided into four subgroups. Subgroup I strains did not have antigens in common with other serotypes, whereas subgroup II strains had antigens in common with serotype 4; subgroup III strains had antigens in common with serotype 10, and subgroup IV had antigens in common with serotypes 1, 9, and 11. The indirect hemagglutination test using unheated whole-cell saline extract as the antigen detected serotype-specific activity. Quantification of serotype-specific and group-specific antigens by coagglutination and immunodiffusion tests was found useful for identifying strains that belonged to serotype 4 or 7.

Actinobacillus↗

PubMed1990

Seroprevalence of Actinobacillus (Haemophilus) pleuropneumoniae serotype-1 infection in swine herds in Quebec.

Seroprevalence of Actinobacillus (Haemophilus) pleuropneumoniae serotype-1 infection was evaluated in pigs on 7 farms in Quebec. Commercial cross-bred herds A to G, ranging from 110 to 235 sows and infected with A pleuropneumoniae serotype-1 were selected. Five pigs/litter were selected at random and were identified (group 1). Blood samples were obtained from group-1 pigs at 2 to 4, 14, 28, 42, and 56 days of age. Blood also was obtained from group-1 pigs remaining in the postweaning unit at 70 days of age, and from 20 to 40 sows 1 to 3 times. To determine prevalence of seropositive pigs in all age groups for the entire study period in herds C to G, blood samples were obtained from 20 pigs/age group (group 2) selected at random at 28, 42, and 56 days of age at each visit. Group-1 pigs were included when they reached 28, 42, and 56 days of age. Pigs were serologically monitored in herds A and B for 3 months and in herds C to G for 5 to 6 months. Serologic status of pigs at 2 to 4 days of age was not statistically associated with status at 42 days (P = 0.6293) and at 56 days (P = 0.3098) of age for the same pigs. Therefore, seronegative pigs 2 to 4 days old did not seroconvert earlier than did those with detectable maternal antibodies at 2 to 4 days old. Only about 50% of the 70-day-old pigs were seropositive at 56 days. Seemingly, pigs seroconverted late in the postweaning period.(ABSTRACT TRUNCATED AT 250 WORDS)

Actinobacillosis↗

PubMed1990

Studies on the interactions of two different serotypes of Actinobacillus pleuropneumoniae.

In vitro and in vivo interactions of various field strains of Actinobacillus pleuropneumoniae of serotypes 1, 2, 5 and 7 were studied. There was no influence of one serotype over the other when strains belonging to two serotypes were cultivated together in vitro. In vivo interactions showed predominance of serotype 1 over other serotypes when a strain of serotype 1 was inoculated together with a strain of serotype 2 or 5 in mice. Serotype 1 strain remained predominant irrespective of whether it was inoculated before or after the inoculation of serotype 2 strain. The mortality caused by the inoculation of two strains was higher than the mortality caused by a single strain. Early mortality was observed on inoculation of strains of serotype 2, 5 or 7 along with a strain of serotype 1. Both serotypes could be detected in the blood on cultural examination of mice infected with mixed serotypes.

Actinobacillosis↗