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Biomedical subjects

R A Bhatti

Publications and source records attributed to R A Bhatti.

At least 19 recordsLinked to original sources
PubMed1999

The projection of the cervical disc and uncinate process on the posterior aspect of the cervical spine.

BACKGROUND: Surgical techniques of foraminotomy for decompression of the cervical nerve have been well described in the literature. Excessive resection of the facet joint and laminae may decrease segmental stability and increase scar formation. How much bony resection is adequate to remove a soft or hard disc herniation is not known. No studies regarding this subject are available. METHODS: Thirty-nine adult dry bone spines from C3 to C7 were used and four measurements on each vertebra were taken in this study. The first three measurements included the vertical distances between the superior borders of the lamina and the vertebral body measured at the midline of the laminae, the middle of the lamina, and the lamina-facet junction, respectively. The fourth was the horizontal distance between the medial most border of the superior facet and the tip of the uncinate process. RESULTS: No significant differences between male and female specimens were found in any measurements in this study. The mean vertical distances from the superior border of the lamina inferior to the superior border of the vertebral body measured at the three points for all levels were approximately 1-3 mm, although the standard deviations for those were relatively high. The tip of the uncinate process was located from 2 mm at C3 to 1 mm at C6 medial to the medial most border of the superior facet, and then changed to be located 1 mm lateral to the medial most border of the superior facet. CONCLUSIONS: This study suggests that a semicircular laminotomy placed on the inferior aspect of the lamina above may be adequate for a lateral soft disc herniation because the inferior border of the disc is higher than the superior border of the inferior lamina, whereas a traditional foraminotomy is needed for a hard disc pathology.

Adult↗
PubMed1997

Metastatic behavior of prostatic tumor as influenced by the hematopoietic and hematogenous factors.

Metastasis represents a hallmark of the tumor cell's escape from normal cellular behavior to acquired invasive and migratory style. Metastasis of prostate cancer (Pca) depends upon the interplay of a series of hematogenous and hematopoietic factors. We investigated the role of some of those factors implicated in the dissemination process in two separate sublines of adenocarcinoma of the prostate. Our data revealed that (1) the urokinase plasminogen activator activity was significantly higher in R3327-AT3, an aggressive metastatic tumor, as compared to R3327-G, a nonmetastatic tumor of the prostate, (2) the concentration of platelets decreased, and the platelet-aggregating activity increased significantly when the platelets were reacted with exogenous aggregating agents and tumor effusions to suggest that activation of the hemostatic system could protect tumor cells from immunosurveillance and facilitate the process of hematogenous dissemination, and (3) transferrin, which has been reported to have a growth-promoting effect on Pca, did not show any appreciable effect on tumor growth but did alter the level of in vitro adherence which possibly could lead to better attachment and increased invasive behavior of tumor cells.

Adenocarcinoma↗
PubMed1996

Potential role of platelets and coagulation factors in the metastasis of prostatic cancer.

One of the common surgical procedures used in the management of prostate cancer is transurethral resection of the prostate in which the possibility of the escape of tumor cells and their encounter with the hemostatic system is reported to contribute to the threat of hematogenous dissemination. We are reporting about the role of the hemostatic system involving the platelets and coagulation factors in the dissemination process in a tumor model carrying Dunning's R3327 AT3 adenocarcinoma of the prostate whose metastatic behavior is similar to that of human prostatic cancer. Our data revealed that the number of circulating platelets dropped and their aggregation activity increased in tumor-bearing rats as compared to controls. Normal platelets when treated with tumor effusions and reacted with the exogenous aggregating agent collagen exhibited a significant increase in the aggregating activity suggesting that the tumor and its microenvironment were capable of activating the hemostatic system. Out of eight coagulation factors measured only factors XI and XII were significantly decreased in tumor-bearing rats. The role of platelets in the metastatic process is discussed.

Adolescent↗
PubMed1985

The effect of low-dose cyclophosphamide and immunologic exposure upon growth of established Dunning R-3327-G subline rat prostate adenocarcinomas.

Utilizing the Dunning rat prostate adenocarcinoma, a low dose of cyclophosphamide (CY), 30 mg/kg, administered either alone or following diethylstilbestrol (DES) therapy, was as effective as higher levels of CY (100 mg/kg) in ability to initiate tumor regression. A lower dose (10 mg/kg) of CY was initially ineffective. Animals which had been injected with tumor an additional 10 days prior to initiation of CY treatment were apparently more responsive to this mode of chemotherapy. The effect of this additional 10 days of immunologic exposure supports the belief that the activity of CY is augmented by the presence of immunologic competence. All animals which responded favorably toward therapy utilizing CY, alone or in combination with DES, were similarly able to reject subsequent tumor challenges. It is thought that low-dose CY may reduce the immunosuppressive effects observed with higher levels and presumably preserve the helper T cell population necessary to mount secondary immune responses.

Adenocarcinoma↗
PubMed1985

Effect of transfer factor on tumor-associated immunity and tumor growth of the Dunning R-3327G rat prostate adenocarcinoma.

Of importance in the design and application of improved or new modalities of treatment are their evaluation on relevant animal models. In the case of prostate cancer (PCa) the Dunning R-3327 rat prostate adenocarcinoma (PCa), and its variant sublines, is one such experimental tumor model of its human counterpart. In a preliminary study, the effect of transfer factor (TF), one form of passive immunotherapy, on tumor-associated immunity (TAI) and tumour growth and histology of the G subline (a poorly differentiated, fast-growing, androgen sensitive, and poorly metastatic tumour of the Dunning R-3327 rat PCa) has been evaluated. TF prepared from the leukocytes of tumor-bearing animals and nontumor-bearing animals referred to as sensitized (STF) and unsensitized (UTF), respectively, had no significant effect on TAI or tumor size. The only noticeable effect of TF in this study was the presence of variable and moderate lymphocytic infiltrates, necrosis, and degenerative-type cells in tumors of animal recipients of STF. The failure to observe significant differences in TAI among tumor bearing and nontumor bearing animals raises doubt in part, of the immunogenicity of the G subline tumor and its appropriateness, at least for subsequent immunological studies. Further factors considered in this regard, are questions of tumor load, including the possible need for the use of adjuvant, and the parameters and sensitivity of immune responsiveness selected for evaluation and immunocompetency. Subsequent evaluation of the effect of TF on other more immunogenic variant sublines of the Dunning R-3327 rat tumor may yet provide further and more useful information.

Adenocarcinoma↗
PubMed1983

Cell-mediated immunity in prostatic cancer and its diagnostic relevancy.

Cell-mediated immunity (CMI) in prostatic cancer patients to presumptively identified prostatic tumour-associated antigens (TAA) was further evaluated in this study by tube leukocyte adherence inhibition in 504 patients with and without prostatic cancer. Peripheral blood leukocytes from 210 of 312 (67%) prostatic cancer patients possessed significant reactivity to extracts of malignant prostate. However, significant reactivity to malignant prostate was also observed in 89 of 192 (46%) controls comprised of patients with other than carcinoma of the prostate [including 91 patients with benign prostatic hypertrophy of which 46 (51%) possessed significant reactivity to malignant prostate] and healthy adults. With the exception of a significant difference in the reactivity between stage A vs stage C patients, there was no significant correlation between the level of reactivity to malignant prostate and the stage of disease. Had CMI to presumptively identified prostatic TAA been employed as an adjunctive diagnostic criterion to detect prostatic cancer, 191 (38%) of the 504 patients in this study would have been incorrectly diagnosed. The results of this study emphasize the critical need in attempting to delineate tumour-directed immunity from possible concomitant sensitization to tissue- and species-specific antigens for the identification, isolation and physicochemical characterization of what previously have been referred to as presumptively or putatively identified prostatic TAA.

Adenocarcinoma↗
PubMed1982

Immunodiagnosis of prostate cancer: an evaluation of cell-mediated immunity.

Leukocyte adherence inhibition (LAI), a suggested in vitro correlate of cell-mediated immunity, was employed to identify patients with various stages of adenocarcinoma of the prostate on the basis of their degree of reactivity to prostatic tumor-associated antigens. Eighty-one percent of the patients and 56% of the controls were identified correctly. The efficiency of LAI was based on the sensitivity and specificity of the test. Our data revealed the absence of any correlation between patients' clinical stage of the disease and their in vitro reactivity to prostatic tumor-associated antigens.

Aged↗
PubMed1980

Suppression of cytophilic antibody ('arming' factor) in the sera of patients with prostatic cancer by human seminal plasma.

The 'arming' of normal peripheral blood leukocytes (PBL) by cytophilic antibody in the sera of prostatic cancer patients is suppressed by pretreatment of PBL with normal human seminal plasma (HuSPl). Suppression of cytophilic antibody by HuSPl extends the spectrum of immunologic reactions on which SPl has an immunosuppressive effect and may provide further insight into the possible role of SPl in the natural history of prostatic cancer.

Adult↗
PubMed1980

Effect of human seminal plasma on tumour-associated immunity in patients with adenocarcinoma of the prostate.

Tumour-associated antigen-induced leukocyte adherence inhibition has been used as an in vitro criterion for evaluating the effect of normal human seminal plasma (HuSePl) on cell-mediated anti-tumour-associated immunity in patients with adenocarcinoma of the prostate. Significant (P < 0.01) suppression from the reactivity obtained with unincubated patients' leukocytes to allogenic extracts of malignant prostatic tissue ranging from 16 to 80% was observed in 22 of 25 patients (88%) following preincubation of their leukocytes with HuSePl. The observed suppression of tumour-associated immunity in the presence of HuSePl provides further evidence for the suppressive activity of SePl on a range of in vitro immune response in normal murine and human hosts. It is suggested that these results, together with those demonstrating experimental prostatic cancer from sensitization by spermatozoa and the relationship of prostatic cancer to repression of sexual activity, provide preliminary evidence of the possible participation of SePl as contributory to the natural history of prostatic cancer.

Adenocarcinoma↗
PubMed1980

Suppression of tumor-associated immunity by human seminal plasma and its possible role in the natural history of prostatic cancer.

The immunosuppressive properties of the hormonal and/or secretory milieu or tumor-elaborated factors (in the case of carcinoma) of the prostate have been hypothesized as contributory to the natural history of prostatic cancer. The effect of normal human seminal plasma (HuSP1) on immunity to tumor-associated antigens in patients with prostatic cancer has been evaluated by leukocyte adherence inhibition, a suggested in vitro correlate of cellular immunity. Significant (p less than 0.01) suppression of immunity to malignant prostate ranging from 16 to 80% of the level of reactivity obtained with unincubated patients' leukocytes was observed in 22 (88%) of 25 patients following preincubation of their leukocytes with HuSP1. Suppression of tumor-associated immunity by HuSP1 provides further evidence to studies by other demonstrating SP1 suppression of a range of immune responses in normal murine and human hosts. In addition to the possible biological implications of the immunosuppressive properties of SP1, e.g., as directed toward preservation of the species, whereby under normal conditions tolerance to spermatozoa in the male tract and in the female tract, following coitus, is maintained, it is hypothesized on the basis of collation of studies demonstrating experimental prostatic cancer from sensitization by spermatozoa and the relationship of prostatic cancer to repression of sexual activity, that SP1 may play a significant role in the natural history of prostatic cancer.

Adenocarcinoma↗
PubMed1979

Effect of human seminal plasma on tumour-associated immunity in prostatic cancer. A preliminary report.

Evidence of significant suppression of tumour-associated immunity in patients with prostatic cancer by human seminal plasma (HuSPl) has been observed. Collation of the immunosuppressive property of HuSPl in this and previous studies, together with recent studies demonstrating experimental induction of prostatic cancer by spermatozoa and the relationship of prostatic cancer to sexual activity are suggestive of an etiologic role for SPl in prostatic cancer.

Adenocarcinoma↗
PubMed1979

Further evaluation of the effect of estrogen on tumor-associated immunity in prostatic cancer.

Reactivity of leukocytes to allogeneic extracts of malignant prostate from patients with prostatic cancer, as evaluated by antigen-induced leukocyte-adherence inhibtion, was significantly suppressed in the presence of diethylstilbestrol diphosphate. The observed suppression of tumor-associated immunity in the presence of exogenous estrogen provides further evidence supporting earlier studies that demonstrated estrogenic suppression of nonspecific cellular responsiveness, as evaluated by phytohemagglutinin-induced lymphocytic blastogenesis, and for the initally suggested concern over the efficacy of estrogenic therapy and its adverse effect on host cell-mediated immunologic responsiveness.

Antigens, Neoplasm↗
PubMed1979

Arming of normal leukocytes with sera from patients with adenocarcinoma of the prostate.

A tumor-associated antigen-induced leukocyte adherence inhibition assay was used to evaluate the effect of serum from patients with adenocarcinoma of the prostate on the antitumor reactivity of normal leukocytes. Peripheral blood leukocytes from 53 normal (control) subjects were armed with serum from 22 patients with localized (Stage A) and metastatic (Stage D) prostatic cancer and reacted with allogenic extract of malignant prostate as specific tumor-associated antigen. Leukocytes pre-treated with serum from patients with Stage A cancer show significantly stronger responses to malignant prostate than do those pretreated with serum from patients with Stage D cancer, which induced little or no response. This may be attributed to an "arming factor" present in the sera of patients with an initial stage of prostatic cancer which appears to be capable of sensitizing normal leukocytes and making them specifically reactive to tumor extract. The specificity of arming with individual and pooled patient's sera was delineated by the use of extracts from other genitourinary tumors.

Adenocarcinoma↗