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Biomedical subjects

A Ranki

Publications and source records attributed to A Ranki.

At least 55 records · Page 3Linked to original sources
PubMed1997

Erythema elevatum diutinum in association with coeliac disease.

Erythema elevatum diutinum (EED) has been described in association with several immunological or infectious diseases. We describe a female patient who presented with clinically and histologically typical EED in whom previously undiagnosed coeliac disease was found. Appearance of EED lesions was preceded by widespread joint pains. In extensive laboratory tests, the only abnormal findings were an elevated erythrocyte sedimentation rate (ESR) and decreased haemoglobin and folic acid levels. Later, IgA and IgG type antireticulin and antigliadin antibodies were detected. Serum total IgA was elevated but no paraproteinaemia was found. In lesional skin, granular deposits of IgA and C3 were seen at the dermo-epidermal junction. A duodenal biopsy revealed total villous atrophy. Dapsone treatment was partly effective but complete healing of the EED lesions was achieved only after the introduction of a strict gluten-free diet. The patient has now remained symptom-free on the diet for 1.5 years.

Celiac Disease↗
PubMed1997

Photosensitivity in lupus erythematosus, UV photoprovocation results compared with history of photosensitivity and clinical findings.

Photosensitivity, one of the presenting symptoms in lupus erythematosus (LE), is still poorly defined and varying prevalence figures have been reported. The possibility of a coexisting photodermatosis, especially polymorphous light eruption (PLE), has often not been taken into account. We report the results of ultraviolet A (UVA) and B (UVB) photoprovocation tests in 67 clinically photosensitive patients who had confirmed discoid LE (DLE), systemic LE (SLE) or subacute cutaneous LE (SCLE). The results are compared with a detailed history of photosensitivity and with clinical and serological findings. A pathological photoprovocation reaction, graded as weak, moderate or strong, was induced with either UVA or UVB in 69% of patients with LE, in 100% of those with SCLE, in 70% of those with SLE and in 64% of those with DLE, but in none of 14 controls. Only 16% of the pathological reactions were strong and long-lasting, resembling LE lesions, while 48% were moderate or weak and transient, clinically like PLE. Fifty-three per cent of the provocation reactions which were biopsied showed a PLE-like histology or a non-specific inflammatory reaction, and most of them were clinically moderate or weak reactions of short duration. In the remaining, mostly clinically strong or long-lasting reactions, the histology was consistent with LE. A history of sunlight sensitivity did not predict a pathological photoprovocation result but a positive association between the presence of SSA/Ro or SSB/La antibodies and a pathological photoprovocation reaction was found. We have shown that PLE coexists with LE and that both PLE- and LE-like lesions can be induced with UV radiation in LE patients.

Adolescent↗
PubMed1996

Interleukin-10 gene expression induced by HIV-1 Tat and Rev in the cells of HIV-1 infected individuals.

The role of cytokines in the regulation and function of the immune system is of great importance. In human immunodeficiency virus (HIV) infection, with progressive deterioration of cell-mediated immune response, cytokines are dysregulated. We have therefore investigated cytokine mRNA expression in type-1 and type-2 helper T cells of HIV-seropositive (HIV+) individuals, stimulated with mitogen (leukoagglutinin) and HIV-1 Tat and Rev peptides, previously found to induce proliferative T-cell responses in these individuals. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect interleukin 2 (IL-2), interferon gamma (IFN-gamma), IL-4, and IL-10 mRNAs. There was no difference in the mRNA expression of these cytokines when the cells of HIV-infected or noninfected individuals were polyclonally stimulated with the mitogen, as all cytokine mRNAs were detected in both groups. Baseline cytokine expression of unstimulated cells was, however, different in these two groups: the cells of HIV+ persons did not show comparable expression of mRNAs to HIV-seronegative (HIV+) individuals. When the cells of HIV+ individuals were stimulated with the peptides, 70% of the cases showed IL-10 mRNA expression, 20% IFN-gamma, and 10% IL-2, with no detection of IL-4 mRNA in any of the cases. Our results thus show that HIV-specific T-cell antigens induce production of IL-10 in HIV-infected individuals. The increase in IL-10 demonstrated here may have a role in hyperactivation of B cells, as well as in immunosuppression of T cells often seen in HIV-infected individuals.

Actins↗
PubMed1996

The international epidemiology of disseminated Mycobacterium avium complex infection in AIDS. International MAC Study Group.

OBJECTIVE: To determine rates of disseminated Mycobacterium avium complex (MAC) infection among AIDS patients in developed and developing countries, and to determine whether different rates reflect differences in exposure or immunity, or both. DESIGN: Prospective cohort study. SETTING: University hospitals and outpatient AIDS programs. METHODS: HIV-infected subjects with CD4 counts < 200 x 10(6)/l were interviewed and had CD4 lymphocyte counts, blood cultures for mycobacteria (baseline and at 6 months), and skin tests with purified protein derivative (PPD) and M. avium sensitin. RESULTS: Among 566 study patients rates of disseminated MAC were 10.5-21.6% in New Hampshire, Boston and Finland compared to 2.4-2.6% in Trinidad and Kenya (P < 0.001). PPD skin test reactions > or = 5 mm were present in 20% of patients from Kenya compared to 1% at other sites (P < 0.001). Among patients from the United States and Finland, multiple logistic regression indicated that occupational exposure to soil and water was associated with a decreased risk of disseminated MAC, whereas the following were associated with an increased risk of disseminated MAC: low CD4 count, swimming in an indoor pool, history of bronchoscopy, regular consumption of raw or partially cooked fish/shellfish and treatment with granulocyte colony-stimulating factor. CONCLUSIONS: Rates of disseminated MAC in AIDS are higher in developed than developing countries and are due to both differences in exposure and differences in immunity. These data provide a rationale for prevention of MAC through both active immunization and reduction in exposure to the organism.

AIDS-Related Opportunistic Infections↗
PubMed1996

Simultaneously detected aberrant p53 tumor suppressor protein and HPV-DNA localize mostly in separate keratinocytes in anogenital and common warts.

The E6 oncoprotein of human papillomavirus (HPV) is known to inactivate the control function on cell cycle exerted by p53 tumor suppressor protein in vitro by binding to p53 and thus facilitating the degradation of p53. We have applied a simultaneous in situ demonstration method for detecting p53 protein and HPV-DNA on formalin-fixed tissue sections, and investigated the in vivo interrelationship of p53 protein and HPV-DNA. Immunohistochemical staining for p53 protein with polyclonal and monoclonal antibodies, recognizing both wild-type (wt) and mutated p53 protein, was performed first and in situ DNA hybridization (ISH) for HPV types 6/11 or 16/18 with digoxigenin-labelled probes thereafter. 47% (25/53) of 48 histologically confirmed primary or recurrent condylomata acuminata (CA), 2 Bowenoid papulosis (BP) and 3 common wart (CW) biopsies, positive for HPV 6/11 or HPV 16/18 DNA, showed keratinocytes immunopositive for p53 protein. Of these, 11 lesions with abundant numbers of p53-positive cells were further analyzed with the double method. Signals for abnormal p53 protein and HPV-DNA were detected in separate cell nuclei in all biopsies and, additionally, in the same cell nuclei in 3 biopsies (1 BP, 1 CA, 1 CW). Usually the p53 positivity localized more basally in the epidermis than HPV-DNA, although p53- and HPV-positive keratinocytes were always located closely. The findings were similar for HPV-types 6/11 and 16/18. Our finding of both p53 and HPV-6/11 signals in the same cell nuclei may indicate complexing of p53 and low-risk HPV's without degradation of p53. Our results show abnormal p53 expression in HPV-infected skin lesions, and suggest that p53 protein is susceptible to aberrations even in the cells in the vicinity of productive HPV infection. However, it is not yet fully understood how HPV interferes with p53 protein in these cells.

Adult↗
PubMed1995

Helper and cytotoxic T cell responses of HIV type 1-infected individuals to synthetic peptides of HIV type 1 Rev.

In cell-mediated immunity T cells recognize peptide fragments of the antigenic protein in association with major histocompatibility complex (MHC) proteins. Synthetic 9- to 16-mer peptides have been widely used to identify the region(s) of a protein that act as T cell epitope. Here, we report antigenic peptides identified on HIV-1 regulatory protein Rev. Four synthetic peptides (amino acids 9-23, 25-39, 33-48, and 41-56) were first shown to stimulate T helper (Th) cell proliferation in peripheral blood lymphocytes (PBLs) derived from HIV-seropositive (HIV+) individuals. The same peptides induced cytotoxic T lymphocyte (CTL) activities toward the autologous target cells incubated with the peptides. Both responses were specific to the HIV infection as HIV-seronegative (HIV-) control individuals showed no significant proliferative or cytotoxic activity. The proliferating cells were CD4+ T cells, and CTL activity was mediated by CD8+ human leukocyte antigen (HLA)-restricted T cells. The identification of peptides containing epitopes that can induce both Th and CTL responses to regulatory proteins of HIV-1 in infected individuals might be important for vaccine development against AIDS. Since early regulatory proteins of HIV are expressed by the infected cells before the initiation of the synthesis of structural proteins, a CTL response against these proteins could destroy the infected cells before the release of infectious virions.

Amino Acid Sequence↗
PubMed1995

Abundant expression of HIV Nef and Rev proteins in brain astrocytes in vivo is associated with dementia.

OBJECTIVE: To relate the expression of HIV regulatory proteins and HIV-specific mRNA in the brain cells of infected individuals with clinical neurological disease. DESIGN: Formalin-fixed postmortem brain tissue from 14 HIV-infected adult patients, with previous repeated neurological and neuroradiological examinations, was studied by immunohistochemical and molecular biological methods. Samples from non-infected brains served as controls. METHODS: Immunohistochemistry with monoclonal antibodies (MAb) was combined with in situ RNA hybridization. Target cells were identified with MAb to glial fibrillary acidic protein (GFAP; astrocytes), CD68 (activated macrophages) and Ricinus communis agglutinin (RCA-1; microglia, endothelial cells). For HIV, a panel of MAb against HIV Nef, Tat, Rev and Env proteins or probes specific for all classes of mRNA (nef), for singly or non-spliced mRNA (env) and for non-spliced mRNA (gag/pol) were used. RESULTS: Nef protein was detected in subcortical or subpial astrocytes in seven out of 14 samples, and in multinucleated giant cells in two cases. Gag/pol or env mRNA-expressing astrocytes were detected in four cases. In four out of five cases studied, HIV Rev, but not Tat, was also expressed in astrocytes. Six out of the seven patients with Nef-positive astrocytes had suffered from moderate to severe dementia. The patient with most rapidly progressing severe dementia showed extensive HIV mRNA expression together with Nef and Rev expression in astrocytes. CONCLUSION: In adult human brain, astrocytes are infected by HIV and preferentially express HIV Nef and Rev proteins but are also sometimes productively infected. Astrocyte infection is associated with moderate to severe dementia which agrees with recent knowledge on the housekeeping activities of astrocytes and their eventual role in learning and memory.

AIDS Dementia Complex↗
PubMed1995

Relation of p53 tumor suppressor protein expression to human papillomavirus (HPV) DNA and to cellular atypia in male genital warts and in premalignant lesions.

Functional disturbance of p53 tumor suppressor protein contributes to uncontrolled cell growth. Human papillomavirus (HPV) E6 oncoproteins bind to wild-type p53 and abrogate its function. Our objective was to elucidate the relation of aberrant p53 protein expression to HPV DNA and cellular atypia in male genital warts and premalignant lesions. Immunohistochemically detectable p53 protein expression was studied in 35 male anogenital warts with low-level or no keratinocyte atypia (histologically confirmed condylomata acuminata), in 25 lesions with bowenoid papulosis (BP; carcinoma in situ) histology, and in 10 non-condyloma lesions using immunostaining with three established antibodies recognizing full-length wild-type accumulated p53 protein, or its conformational mutants. HPV DNA specific for HPV 6/11, 16/18, or 31/33/35 was identified by in situ hybridization or by polymerase chain reaction (PCR) - based amplification. Both nuclear and cytoplasmic keratinocyte immunostaining for p53 protein was detected in 41% of condylomata with no keratinocyte atypia and in 42% of condylomata with slight nuclear atypia or with bowenoid papulosis histology. No association of aberrant p53 expression with any specific HPV type or with HPV DNA was observed. Normal skin and some other penile dermatoses were negative for p53 immunostaining. In the follow-up biopsies of 16 BP patients, treated with CO2 laser, recurrence of atypia was seen exclusively in lesions initially positive for both HPV DNA and p53 protein. Our results show that a few cells in male genital warts even with no cellular atypia may express abnormally sequestered or loss-of-function p53 protein, and that concomitant presence of any type of HPV DNA is associated with recurrencies or progression of premalignant changes.

Bowen's Disease↗
PubMed1994

Zidovudine reduces intrathecal immunoactivation in patients with early human immunodeficiency virus type 1 infection.

OBJECTIVE: To evaluate the effect of zidovudine on human immunodeficiency virus type 1 (HIV-1)-associated central nervous system infection in Centers for Disease Control and Prevention stage II or III disease. DESIGN: In an open-ended trial, patients received 500 mg of zidovudine twice a day for 12 months. Lumbar punctures, neurological, neuropsychological, and neuroradiological examinations were repeatedly performed during the trial period and were compared with pretrial values. In 11 patients post-trial neurological follow-up of 10 to 20 months was performed. PATIENTS: Initially, 14 volunteers with stage II or III disease and intrathecal synthesis of HIV-1-specific antibodies were enrolled. Additionally, patients had slight neuropsychological disturbance or brain atrophy unrelated to other agents than HIV-1. Two patients dropped out because of poor compliance. MAIN OUTCOME MEASURES: Intrathecal and systemic immune and virological responses, cognitive performance, and brain images were repeatedly monitored. RESULTS: After 6 weeks of zidovudine therapy, initial low-grade pleocytosis and elevated levels of beta 2-microglobulin, both in cerebrospinal fluid and in serum samples, declined. Intrathecal HIV-1 antibody synthesis could no longer be detected in half of the patients after 12 months of zidovudine therapy. Patients with defective cognition transiently improved cognitive speed and flexibility after 6 months of therapy. Slight atrophic brain changes, however, remained unchanged. CONCLUSIONS: Zidovudine reduces intrathecal immuno-activation and transiently improves cognitive functioning in HIV-1-infected subjects who show evidence of central nervous system involvement by HIV-1 but are otherwise asymptomatic.

Adult↗
PubMed1994

Expression kinetics and subcellular localization of HIV-1 regulatory proteins Nef, Tat and Rev in acutely and chronically infected lymphoid cell lines.

Information concerning the expression kinetics and subcellular localization of HIV regulatory proteins is of importance in understanding the viral pathogenesis and may be relevant for drug and vaccine development, as well. We have used combined immunocytochemistry and in situ hybridization to study firstly, the order of expression of regulatory HIV-1 proteins Nef, Rev and Tat in relation to non-spliced and spliced mRNA expression and secondly, the subcellular localization of these proteins in acutely and chronically infected human T-cell lines. We used monoclonal antibodies against HIV-1 Nef, Tat, Rev and gp160, and RNA probes reacting either with all mRNAs (nef) or only with the full-length mRNA (gag-pol). In acutely infected MT-4 and H9 cells, four distinct phases of infection could be defined. In the first phase lasting from 0 to 6 h post-infection, only incoming virus could be demonstrated by gp160 immunocytochemistry. During the second, regulatory phase (6-9 h), abundant cytoplasmic expression of Nef, Rev and Tat proteins and a positive in situ RNA hybridization with the nef probe was seen, while the in situ hybridization with full-length mRNA probe and immunohistochemistry for gp160 were still negative. The productive phase (12-48 h) was characterized by abundant expression of full-length mRNA and gp160, and by the nuclear localization of Nef and Tat proteins. In contrast, an antibody that recognized the RRE binding region of the Rev protein localized Rev in the cytoplasm both during the regulatory and productive phase. During the fourth, cytopathic phase, the expression of mRNA or viral proteins decreased and the regulatory proteins studied were again mainly localized in the cytoplasm. Based on the results, we speculate that HIV Nef may function as a nuclear factor, and that Tat is possibly bound by cellular proteins before its transport to the nucleus.

Cell Death↗
PubMed1994

A sex comparison of rates of new AIDS-defining disease and death in 2554 AIDS cases. AIDS in Europe Study Group.

OBJECTIVES: To compare the development rate of new AIDS-defining diseases between 566 women and 1988 men with AIDS who were infected with HIV via the same routes (mainly by sharing drug injecting equipment and heterosexual sex). DESIGN: Information on patient follow-up after AIDS diagnosis was obtained by retrospectively reviewing case notes. METHODS: The 2554 men and women were followed from the time of AIDS diagnosis as part of the multicentre AIDS in Europe study, which examined AIDS cases diagnosed at 52 centres in 17 European countries between 1979 and 1989. Incidence of AIDS-defining diseases and demographic variables were recorded for all patients and CD4 lymphocyte count at the time of AIDS diagnosis for approximately half the patients. RESULTS: Only toxoplasmosis and herpes simplex virus ulceration showed statistically significant differences in occurrence rate between women and men [relative risks (RR), 1.51 and 3.44; 95% confidence interval (CI), 1.51 1.09-2.08 and 3.44 1.92-6.23, respectively] which remained after adjusting for imbalances in other variables. For both diseases, the additional absolute rate in women was approximately three per 100 person-years at risk. Survival after AIDS diagnosis was also similar between the two sexes (RR, 0.96; 95% CI, 0.86-1.08). CONCLUSION: There appears to be little difference between women and men in the clinical course of AIDS.

AIDS-Related Opportunistic Infections↗
PubMed1994

Successful amplification of DNA specific for Finnish Borrelia burgdorferi isolates in erythema chronicum migrans but not in circumscribed scleroderma lesions.

Early diagnosis of Borrelia burgdorferi infection, hampered by the absence of detectable antibodies in most patients with erythema chronicum migrans is important to prevent late-stage neurologic, rheumatologic, and skin disorders. Furthermore, B. burgdorferi has been claimed to be the causative agent in localized scleroderma (morphea). We used PCR amplification to search for B. burgdorferi outer surface protein OspA-specific sequences in DNA obtained from lesional skin biopsies on Finnish patients with clinically suspect erythema chronicum migrans, lymphocytoma, morphea, or with diverse skin manifestations and persistent high antibodies to B. burgdorferi flagellar antigen. Seronegative patients with other skin lesions served as controls. The amplicons obtained with primers specific for B. burgdorferi type strain B31 ospA sequence did not hybridize to the corresponding probes, and thus the DNA amplified from a Finnish B. burgdorferi erythema chronicum migrans skin isolate was sequenced. This 98-nucleotide sequence of ospA (332-429) showed 11% to 14% nucleotide divergence compared with the North American type strain (B31), several European strains, and an East Siberian tick strain. The sequence was almost identical (99%) to a Swedish isolate from acrodermatitis chronica atrophicans. Using oligonucleotides specific for the Finnish strain, a positive polymerase chain reaction-based hybridization was obtained in six of seven untreated erythema chronicum migrans patients infected in Finland or in Estonia, and in the lymphocytoma patient. Only two of the erythema chronicum migrans patients had IgG or IgM antibodies to flagellin. However, all seven morphea lesions as well as the other lesions were polymerase chain reaction negative. Polymerase chain reaction-based hybridization of B. burgdorferi OspA gene from skin-derived DNA thus provides a sensitive and specific diagnostic tool. In conditions not unequivocally known to be caused by B. burgdorferi, like in morphea, this assay was negative. We also demonstrate that peri-Baltic B. burgdorferi isolates show homology in their OspA genes but differ from geographically more distant isolates.

Antibodies, Bacterial↗
PubMed1994

Polymorphism of the tumor necrosis factor genes in patients with dermatitis herpetiformis.

In 18 patients with dermatitis herpetiformis (DH) of whom 16 were HLA-DR3 positive and 14 had the HLA-B8, -DR3 haplotype, the frequencies of known mutations of the tumor necrosis factor alpha (TNF-alpha) and TNF-beta genes were investigated using restriction fragment length polymorphism analysis and the single-strand conformational polymorphism technique. In DH, the phenotype frequency (28%) and allele frequency (0.58) of the rare TNF-beta allele TNFB*1 were significantly increased (normal control 12.4% and 0.37). For the TNF-alpha promoter/enhancer polymorphism, the rare allele TNF2 was more frequent in DH patients (11%, 0.47) compared to controls (2%, 0.16). Since functional studies have associated the rare TNFB*1 and TNF2 alleles with a higher secretion of TNF upon activation in vitro, the predominance of these two 'high-response' TNF alleles in DH patients may represent a genetic basis for the chronic inflammatory response in the skin and mucosal tissues of patients with DH.

Alleles↗
PubMed1993

HIV-1 specificity of cerebrospinal fluid and serum IgG, IgM, and IgG1-G4 antibodies in relation to clinical disease.

The reactivities of intrathecal and serum IgG and IgM, and IgG1-4 subclass antibodies to various HIV-1 proteins were assessed by immunoblotting at various stages of HIV-1 infection. All patients were examined neurologically including CT and/or MRI, and with HIV-1-specific and nonspecific tests of the cerebrospinal fluid (CSF). In early infection, the occurrence of anti-gag antibodies in both CSF and serum was higher than that of anti-pol antibodies among all IgG subclasses (P < 0.05). Also in late infection, anti-gag IgG1 response was most frequent (P < 0.04), while anti-gag IgG3 and IgG4 reactivities predominated over similar anti-pol antibodies (P < 0.05, respectively). Of anti-pol reactivities, in the CSF of subjects at early infection anti-p32 IgG and IgG1 antibodies were more frequent than in patients at late stages (P < 0.015). In late infection, however, the occurrence of anti-p64 IgM and IgG2-4 antibodies of both CSF and serum was higher than at early stages (P = 0.014). Regarding anti-env response, in patients with advanced infection, the CSF and serum IgG subclass reactivity against gp120 was restricted to IgG1. The CSF of individual patients with HIV encephalopathy showed a higher or similar occurrence of polyisotypic anti-gag and anti-pol IgG3 antibodies than corresponding serum. These results indicate association between declining frequency of anti-pol p32 and anti-env gp120 antibodies and severity of HIV-1 disease.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS Dementia Complex↗
PubMed1993

Evidence of previous infection with Mycobacterium avium-Mycobacterium intracellulare complex among healthy subjects: an international study of dominant mycobacterial skin test reactions.

Skin tests with 0.1 mL of intermediate-strength Mycobacterium tuberculosis purified protein derivative (PPD) and 0.1 mL of Mycobacterium avium sensitin were conducted on 484 healthy subjects from diverse geographic sites. Reactions of > or = 5 mm to one antigen that exceeded the reaction to the other by > or = 3 mm were considered M. avium- or PPD-dominant. PPD-dominant reactions were more frequent at sites where routine Bacille Calmette-Guérin immunization is done or where there are high rates of tuberculosis: New Hampshire, 2%; Boston, 7%; Finland, 14%; Trinidad, 26%; and Kenya, 28%. However, rates of M. avium-dominant reactions ranged from 7% to 12% at all sites. Analysis of dominant reactions based on a more stringent 10-mm minimum reaction size showed similar trends. These data suggest that exposure to MAC is similar in developed and developing countries but that broad mycobacterial immunity is greater in developing countries and may contribute to the lower rates of disseminated MAC infections in AIDS in these areas.

Adult↗