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Biomedical subjects

H S Juneja

Publications and source records attributed to H S Juneja.

At least 55 records · Page 3Linked to original sources
PubMed1988

In-vivo and in-vitro association between leukemic cells and marrow stromal cells: a murine model.

Several reports indicate that marrow stromal cells are conducive to development of both myeloid and lymphoid leukemic cell lines in vitro. We present data on an in-vitro/in-vivo murine model that establishes that: (i) murine LL cell lines (L5178Y, P388 and L1210) invade the bone marrow when injected via the tail vein; (ii) degree of marrow invasion by LL can be determined quantitatively; (iii) there is a close association or adherence between MSC and LL cells in vivo; and (iv) in-vitro adherence of murine LL cells to MSC can be quantitated. This in-vitro/in-vivo murine model will be helpful in deciphering the importance of heterotypic adherence between marrow stromal cells and leukemic cells in vivo.

Animals↗
PubMed1987

Involvement of prostaglandin A1 in interrupting early pregnancy in Syrian golden hamsters.

The effects of a single administration of authentic prostaglandin A1 intravaginally in early pregnant hamsters were investigated. A single dose of 1 mcg/animal given on day 4 of pregnancy inhibited the appearance of embryonic swellings when observed on day 8 of pregnancy. A significant fall (p less than 0.01) in FSH with a rise (p less than 0.03) in prolactin concentration in the serum and no change in LH levels were observed. The pituitary content of prolactin showed a significant decrease (p less than 0.0006) with no change in FSH and LH contents. Progesterone concentration in the serum was markedly reduced (p less than 0.002), along with that of the ovaries (p less than 0.01). The decline in progesterone concentration coincided with the absence of corpora lutea and the embryos. However, no change in ovarian weights was observed. These results indicate the contragestive potential of prostaglandin A1. It appears to act as a luteolytic agent by disrupting the luteotropic complex (FSH:prolactin ratio).

Animals↗
PubMed1987

Androstane therapy to treat aplastic anaemia in adults: an uncontrolled pilot study.

During the past 9 years, 43 adult patients with severe aplastic anaemia have been treated with a combination of 3 alpha etiocholanolone and nandrolone decanoate in an uncontrolled pilot study. Eleven patients were considered acute and the remainder as chronic severe aplasia. 50% (22 patients) had a haematopoietic recovery and 40% have had a sustained remission varying from 1.5 to 8 years. Three patients who did not respond to 3 alpha etiocholanolone had a haematologic response when treated with the isomer 3 beta etiocholanolone. The recovery did not appear to be associated with age or duration of marrow aplasia. In view of the reproducible chemical structure of these androstanes, we believe this group of steroids should be evaluated further in the treatment of severe aplastic anaemia.

Acute Disease↗
PubMed1987

Abnormality of platelet size and T-lymphocyte proliferation in an autosomal recessive form of dyskeratosis congenita.

Dyskeratosis congenita (DC) is a rare familial hematologic disorder that has various modes of inheritance. We have studied 2 siblings with DC. 1 sibling had thrombocytopenia, which responded to therapy with nandrolone decanoate and oxymetholone. Platelets were abnormally small, which indicates that a qualitatively abnormal megakaryocytopoiesis is a feature of DC. Myeloid and erythroid progenitors in specimens of the blood and bone marrow from both siblings were either absent or greatly reduced in numbers. The qualitatively abnormal megakaryocytopoiesis, and the quantitative abnormality of hematopoietic progenitor cells committed to myelopoiesis and erythropoiesis, indicates involvement of the pluripotent stem cell in DC. Cytogenetic studies of the bone marrow and peripheral blood lymphocytes from these patients showed normal karyotypes, a normal sister chromatid exchange frequency, and a rapid proliferation of peripheral T lymphocytes, a feature of the disorder that has not been reported previously.

Blood Platelets↗
PubMed1987

Acute monoblastic leukemia with a single chromosomal rearrangement involving breakpoints on chromosomes 8 and 16, 46, XX, t(8;16)(p11;p13).

We report a case of acute nonlymphoblastic leukemia (M5) with a rare cytogenetic abnormality involving chromosomes 8 and 16, t(8;16)(p11;p13). The leukemic blasts were determined to be monocytic by cytochemical and immunochemical studies. Morphological changes of the leukemic cells in response to phorbol myristate acetate further supported their identification as monocytic in nature. This chromosomal abnormality has apparently been reported only thrice in the literature. Translocation (8;16)(p11;p13), though rare, may be of primary importance in the process of leukemogenesis in some cases of histiocytic/monocytic malignancies.

Acute Disease↗
PubMed1987

Auer rod-like inclusions in prolymphocytic leukemia.

Auer rod-like inclusions (ARLI) can be seen in B cell malignancies but are very rare in prolymphocytic leukemia (PLL). Prolymphocytes with ARLI from a patient with PLL were examined using cytochemical and immunochemical techniques and transmission electronmicroscopy (EM). The lymphoblastic cells gave a positive reaction with antibodies to the gamma heavy chains and kappa light chain. On EM the ARLI were 1-2 micron long, consisting of election-dense crystalline matrix, with a periodicity of 60 A and contained within a single unit membrane. The production of IgG by PLL cells with ARLI has not been previously reported. It is emphasized that in PLL the lymphoblasts can have inclusions resembling Auer rods. Cytochemical and immunochemical studies should be done to avoid a misdiagnosis of acute nonlymphoblastic leukemia.

Aged↗
PubMed1987

Age-related release of prolactin by the pituitary and the pituitary-hypothalamic complex in vitro: an attempt to describe the development of the hypothalamic prolactin-inhibiting and -releasing activities in male rats.

We have recently demonstrated that the pituitary hypothalamic complex (PHC) is a good model for studying interactions between the hypothalamus and pituitary in vitro. The amount of prolactin secreted by the PHC is an index of prolactin secreted by the pituitary in the presence of hypothalamic control, while the amount released by the whole pituitary alone is an index of prolactin secreted in the absence of hypothalamic control. The amount of prolactin secreted by the PHC has been regarded as an index of hypothalamic prolactin-releasing activity (HPRA), while the difference in the amounts of prolactin secreted by the whole pituitary and the PHC is the hypothalamic prolactin-inhibiting activity (HPIA). Attempts were made to correlate HPRA and HPIA to the development of serum concentrations of prolactin from days 7 to 77 in male rats. The HPRA increased steadily from days 7 to 56, decreased significantly on day 63 and thereafter remained unchanged until day 77. The HPIA was low on days 7 and 14 and increased steadily up to day 49, with no further significant variations. The developmental patterns of HPRA and HPIA were comparable up to day 49. Serum concentrations of prolactin increased significantly until day 28 and remained fairly constant until day 49. The weight of the pituitary gland increased from 1.0 +/- 0.03 mg (mean +/- S.E.M.) on day 7 to 7.76 +/- 0.32 mg on day 63 and remained unchanged thereafter. The weight of the hypothalamic islet was 31.5 +/- 2.88 mg on day 7, 34.83 +/- 1.45 mg on day 14 and 50.4 +/- 4.01 mg on day 21. After day 21 the weights of the hypothalamic islets were not significantly altered, except on day 49. It was concluded that serum concentrations of prolactin are regulated by interaction or competition between HPRA and HPIA at the level of the pituitary.

Aging↗
PubMed1986

Role of marrow stromal cells in the establishment of a transformed lymphoblastic B-cell line from a normal human subject.

A monoclonal human B-lymphoblastoid cell line (UTMB-460) arose spontaneously from the bone marrow of a normal healthy woman who was seropositive for an EB-virus infection. Chromosomally, the UTMB-460 cells are near tetraploid, with a specific translocation (8;9) (p11.2; p24), and have surface IgMk. The UTMB-460 cells are resistant to killing in vitro by spontaneous and rIFN alpha 2 and rIL-2 stimulated NK cells from the patient and other normal subjects, but are killed by lymphokine activated killer cells. The index patient has not developed leukemia/lymphoma during the follow-up interval of 22 months. The growth of UTMB-460 cells is supported by undefined growth factors in FCS and by BCGF in the absence of FCS. rIL-2 stimulates DNA synthesis by UTMB-460 cells. The UTMB-460 cells were adherent to the normal MSC in the primary culture and show specific heterotypic adherence to normal MSC when compared to skin fibroblasts. In addition, 6/6 normal marrow stromal cells and 4/6 normal skin fibroblasts induced growth of colonies from UTMB-460 cells. These data suggest that MSC interacted with the transformed cells (UTMB-460) in vitro and played a critical role in the establishment of the UTMB-460 cell line.

Adult↗
PubMed1986

The choice of a model for studying the hypothalamus-pituitary interactions in vitro.

Comparative studies on the release of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin (Prl) by the whole pituitary, pituitary plus hypothalamus and pituitary-hypothalamus complex (PHC) were undertaken to choose an appropriate model for studying the hypothalamus-pituitary interactions in vitro and to relate the importance of the intact neural connections between pituitary and hypothalamus on hypothalamus-pituitary interactions. Also the effect of including dopamine (DA) at 1 X 10(-7) mol/1 in these different in vitro systems on the release of LH, FSH and Prl was investigated. The pituitary released increasing amounts of LH and FSH at 2, 4 and 6 h but the amount of Prl released remained unchanged. The rates of release of LH, FSH and Prl by the pituitary were different and were characteristic of each hormone. Co-incubation of pituitary with hypothalamus stimulated the release of LH and FSH but inhibited the release of Prl. Pituitary-hypothalamus complex behaved almost identical to behaved almost identical to pituitary plus hypothalamus system. Inclusion of 1 X 10(-7) M DA in the incubation medium stimulated the release of LH (80%) but inhibited the release of Prl (71%) by PHC. FSH was unaffected. DA had no significant effect on the release of LH, FSH and Prl by pituitary and pituitary plus hypothalamus systems. It is suggested that PHC is the system of choice for studying hypothalamus-pituitary interactions in vitro.

Animals↗
PubMed1986

Ontogeny of serum and pituitary gonadotrophins in male rats treated with low doses of 5 alpha-dihydrotestosterone.

The effect of s.c. daily injections of 10 or 1000 ng 5 alpha-dihydrotestosterone (DHT)100 g body weight from birth to day 21, or from days 26 to 117 of age, on the changes in concentration of serum and pituitary gonadotrophins was investigated in male rats. Treatment with 10 ng DHT from days 1 to 21 depressed serum FSH, but not LH, at day 7, while 1000 ng DHT depressed both serum LH and FSH. Treatment with both doses of DHT reduced pituitary levels of LH and FSH at day 7, with FSH being more depressed than LH. Treatment with 10 ng DHT from days 26 to 117 increased serum FSH from days 82 to 117, while 1000 ng DHT did not have this effect. Treatment with 1000 ng, but not 10 ng, DHT between days 26 and 117 reduced pituitary levels of LH and FSH at day 40. Rats treated with the two doses of DHT from days 26 to 117 showed a difference in the responsiveness of the pituitary to LH-releasing hormone (LHRH). Treatment with 10 ng DHT enhanced LHRH-induced release of LH without affecting FSH release, while 1000 ng DHT depressed LHRH-induced release of FSH but not of LH. These findings support the view that DHT may play a modulatory role in the ontogeny of serum gonadotrophins and the responsiveness of the pituitary to LHRH during the onset of puberty in the male rat.

Animals↗
PubMed1985

Normal human marrow stromal cells induce clonal growth of human malignant T-lymphoblasts.

The effect of marrow stromal cells (MSC) on the clonal growth of a human malignant T-lymphoblast (MTL) cell line was investigated in a bilayer culture system. The MSC consistently stimulated clonal growth of MTL, and no stimulatory humoral factor was present in the medium conditioned by the MSC. These observations and other reports suggest that marrow stromal cells may provide a microenvironment in vivo that is not only conducive to the growth of malignant lymphoblasts, but may actually enhance proliferation of malignant T-lymphoblasts in the bone marrow.

Alkaline Phosphatase↗
PubMed1985

Effect of castration and steroid treatment on the release of gonadotropins by the rat pituitary-hypothalamus complex in vitro.

Comparative in vitro studies on the release of LH and FSH by pituitary-hypothalamus complex (PHC) with intact portal plexus and whole pituitary (PI) from adult male rats showed that PHC released LH at a greater rate and in larger amounts than PI. PHC and PI released FSH in comparable amounts and rates. Attempts were made to correlate serum gonadotropin levels to that released by PHC and PI at 1, 3, 7, 14, 21 and 46 days of post-castration (PC). Sham operated animals served as controls. Castration increased serum LH and FSH levels but in different profiles. CPHC and CPI (PHC and PI from castrated rats) released less LH than NPHC and NPI (PHC and PI from sham operated controls) till day 14 PC after which CPHC and CPI released more LH than NPHC and NPI respectively. Castration abolished the intrinsic capacity of PHC to secrete more LH than PI. CPHC and CPI secreted significantly less FSH than NPHC and NPI at 1, 3 and 7 days PC. At days 14 and 21 of post-castration PCNCP or CPI and NPHC or NPI released similar amounts of FSH. Administration of 5 alpha-dihydrotestosterone (DHT, 1 mg/rat/day) or estradiol valerate (EV, 1 microgram/rat/day) immediately following castration prevented the rise in serum LH and FSH but increased the amounts of LH and FSH released by CPHC and CPI. The treatment caused a marked stimulation of FSH released by CPI.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Basophil function in patients with chronic myelogenous leukaemia.

We have compared the release of histamine from basophils isolated from six patients with chronic myelogenous leukaemia (CML) and seven normal controls. No differences were noted in the release induced by rabbit anti-human IgE. However, basophils from CML patients released less than 20% of their intracellular histamine when challenged with the anaphylatoxin C5a at a concentration that caused greater than 50% release from normal basophils. Furthermore, basophils from CML donors showed a significantly lower release in the presence of the calcium ionophore A23187. These results suggest that basophils from CML patients have an inherent defect.

Basophils↗
PubMed1985

Functionally abnormal marrow stromal cells in aplastic anemia.

We studied the myeloid colony-stimulating activity (CSA) of marrow stromal cells (MSC) derived from normal subjects and patients with aplastic anemia, acute leukemia, and other myeloproliferative disorders. CSA of the MSC was determined in a bilayer system. Feeder layers with varying numbers of MSC (10(4) to 2 X 10(5)) were used. Of 40 MSC tested, 39 stimulated myeloid colony formation by the normal target marrow mononuclear cells. The optimal concentration of MSC exhibiting the maximal stimulation of myeloid progenitors (CFU-GM) varied with different MSC. MSC from normal subjects and from patients with acute leukemia and myeloproliferative disorders were potent stimulators of CFU-GM differentiation. In contrast, MSC from patients with aplastic anemia had poor CSA, suggesting that the marrow microenvironment is functionally abnormal in aplastic anemia.

Anemia, Aplastic↗
PubMed1984

Studies on the effects of low doses of 5 alpha-dihydrotestosterone (DHT) on the basal levels of serum gonadotropins and the sensitivity of the pituitary to luteinizing hormone releasing hormone (LHRH) in adult male rats.

Investigations were undertaken to study the effect of administering s.c. 10, 25, 50, 100, 500 and 1000 ng DHT/rat/day to normal adult male rats, for six weeks, on the basal levels of serum gonadotropin and the sensitivity of the pituitary to LHRH. The control group received olive oil. Animals were weighed and bled via cardiac puncture before the beginning of the treatment and weekly thereafter. After the last bleeding rats were injected intracardially 200 ng LHRH/rat and killed 15 min later. Blood, pituitary and testes were collected. Data were analyzed with respect to the control group and with respect to day zero of the treatment. DHT failed to produce a persistent effect on the serum gonadotropin. 10 and 500 ng DHT suppressed FSH levels significantly on days 21 and 7, respectively. 25, 50, 100 and 1000 ng DHT stimulated the release of FSH on day 42. 10 ng DHT reduced the levels of LH on day 14 of the treatment. 10, 25 and 50 ng DHT increased the sensitivity of the pituitary to release more LH in response to LHRH while 100, 500, 1000 ng DHT inhibited LHRH induced release of FSH. DHT at all doses tested failed to affect intrapituitary levels of LH and FSH. 10, 500 and 1000 ng DHT reduced the weights of the pituitaries as compared to the control group. The data demonstrate effects of DHT which are transient on the basal release of gonadotropins but are more persistent and differential on the sensitivity of the pituitary to LHRH.

Animals↗
PubMed1984

Effect of varying photoperiods on mammary morphology, DNA synthesis, and hormone profile in female rats.

A clear positive correlation between circulating levels of prolactin (Prl) and morphologic development as well as DNA synthetic index in the mammary gland was established in young virgin Holtzman rats exposed to constant light from birth. The observed elevated level of circulating Prl by virtue of its morphogenic and mitogenic properties induced changes in mammary epithelium [numerous actively differentiating terminal end buds into alveolar buds (AB)] highly susceptible for the action of 7,12-dimethylbenz[a]anthracene [(DMBA) CAS: 57-97-6]. Conversely, substitution treatment with melatonin in such a model caused a significant decrease in both Prl and 17 beta-estradiol (E2) levels as well as in the morphologic and DNA synthetic pattern of the mammary gland. Administration of 2-bromo-alpha- ergocryptin in these animals caused a significant decrease in the plasma level of Prl (without affecting the level of E2) and a decrease in the density of AB and in DNA synthesis. These changes impaired the mammary gland responsiveness to DMBA as seen from the significant decrease in the incidence of mammary carcinoma.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1984

The effect of dexamethasone on the growth of bone marrow fibroblasts in aplastic anemia.

To study the characteristics of the microenvironment of human bone marrow, fibroblasts derived from normal and aplastic anemia bone marrow aspirates or core biopsies were grown in culture. Normal bone marrow fibroblasts had a slow logarithmic phase of growth (8 days) with doubling times of 2 to 3 days. Aplastic anemia bone marrow fibroblasts had a rapid logarithmic phase of growth (5 to 6 days) and doubling times of 1 day. Dexamethasone (1 X 10(-8) M) stimulated the growth of normal fibroblasts. Growth of fibroblasts derived from aplastic anemia marrows was, however, inhibited by dexamethasone. Specific binding sites for the hormone were present in the normal fibroblasts (Bmax: 460-770 fmole/mg protein) whereas in the aplastic anemia fibroblasts the amount was very low (Bmax 27-215 fmole/mg protein). These observations suggest that in aplastic anemia, the bone marrow fibroblast, a cell constituent of the marrow microenvironment, has the capacity to develop and grow in vitro. However, this cell is different from normal bone marrow fibroblasts in its growth characteristics and response to dexamethasone.

Anemia, Aplastic↗