Disruption of epithelial gamma delta T cell repertoires by mutation of the Syk tyrosine kinase

Chimeric mice in which lymphocytes are deficient in the Syk tyrosine kinase have been created. Compared with Syk-positive controls, mice with Syk -/- lymphocytes display substantial depletion of intraepithelial gamma delta T cells in the skin and gut, with developmental arrest occurring after antigen receptor gene rearrangement. In this dependence on Syk, subsets of intraepithelial gamma delta T cells are similar to B cells, but distinct from splenic gamma delta T cells that develop and expand in Syk-deficient mice. The characteristic associations of certain T-cell receptor V gamma/V delta gene rearrangements with specific epithelia are also disrupted by Syk deficiency.

Neurologic sequelae in high risk infants--a three year follow up

OBJECTIVE

To determine the neurologic sequelae in high risk infants.

DESIGN

A three year longitudinal follow up.

SETTING

Inborn and outborn infants discharged from the Neonatal Special Care Unit (NSCU) of a referral hospital.

METHODS

High risk infants were identified for follow up using predetermined risk criteria. A detailed neurodevelopmental examination was done 3 monthly in the first year and 6 monthly subsequently. The Amiel-Tison Method, Bayley Scales of Infant Development and Raval's Scale for social maturity were used. EEG was done in children with seizures. Hearing and ophthalmic assessments were done at 6 months.

RESULTS

Three hundred and thirty six high risk infants and 70 normal control infants came for regular follow up. Out of these, 16 (4.8%) had cerebral palsy and 11 had associated mental retardation. Six other children had mental retardation without motor problems. None of the children in the control group had any neurological problems. Sensorineural hearing loss was present in 5 (1.5%) children while 1 subject had corfical blindness. Three children with cerebral palsy had infantile myoclonus, nine had generalized seizures and one child had a focal seizure. The incidence of seizure disorders was 3.9%.

CONCLUSIONS

The incidence of major handicap in our study was low. Many of the risk factors which caused adverse outcome, could have been prevented by good antenatal and perinatal care.

Altered expression of the developmentally regulated NFI gene family during phorbol ester-induced differentiation of human leukemic cells

The nuclear factor I (NFI) family of transcription/replication proteins is required for the cell type-specific expression of a number of cellular and viral genes. There are four evolutionarily conserved NFI genes (NFI-A, -B, -C and -X) that encode DNA-binding proteins of similar or identical DNA-binding specificity. To address the role of this family of highly conserved transcription/replication proteins in cell differentiation and development, we have assessed the expression of NFI proteins (by DNA binding) and mRNAs of each of the four NFI genes during the in vitro differentiation of several human leukemic cell lines. These cell lines differ in their pattern of differentiation upon exposure to the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA). In K562 and OCI/AML-3 cells, the levels of the four NFI mRNAs and the mobility of NFI-DNA complexes present in nuclear extracts changed during treatment with TPA. The TPA-induced change in mobility of NFI-DNA complexes in OCI/AML-3 cells was blocked by an inhibitor of protein synthesis, cycloheximide. These changes in NFI protein and mRNA expression appear to be cell type-or lineage-specific since no changes were seen during the TPA-induced differentiation of HL-60 or U937 cells. These studies indicate that although their DNA-binding specificities are similar, the proteins encoded by the four NFI genes may differ in their biological functions and play distinct roles in hematopoietic development.

Evaluating efficiency of bone marrow harvest and its manipulation--role of CD 34 positivity

We evaluated harvested marrow cells for total nucleated cells (27.49 x 10(9)), absolute 'lymphocyte' count (6.29 x 10(9)) and CD 34 positive cells (3.57 x 10(9)). The same parameters were studied after in vitro manipulation to remove RBCs and plasma. Reinfused WBCs contained 12.87 x 10(9) nucleated cells, 4.25 x 10(9) absolute 'lymphocyutes' and 3.34 x 10(9) CD 34 positive cells. The corresponding figures for loss during in vitro manipulation (tubing, RBCs and plasma) are 14.62 (53.18%), 2.04 (32.43%) and 0.23 x 10(9) (6.44%) cells respectively. Therefore CD 34 positivity may be a better indicator of total yield, loss during manipulation and reinfusion of hemopoietic progenitor cells in bone marrow transplantation.

Drosophila nonmuscle myosin II is required for rapid cytoplasmic transport during oogenesis and for axial nuclear migration in early embryos

The X-linked Drosophila gene spaghetti squash (sqh) encodes the regulatory light chain of nonmuscle myosin II. To assess the requirement for myosin II in oogenesis and early embryogenesis, we induced homozygous germline clones of the hypomorphic mutation sqh1 in otherwise heterozygous mothers. Developing oocytes in such sqh1 germline clones often failed to attain full size due to a defect in ‘dumping’, the rapid phase of cytoplasmic transport from nurse cells. In contrast to other dumpless mutants described to date, sqh1 egg chambers showed no evidence of ring canal obstruction, and no obvious alteration in the actin network. However the distribution of myosin II was abnormal. We conclude that the molecular motor responsible for cytoplasmic dumping is supplied largely, if not exclusively, by nurse cell myosin II and we suggest that regulation of myosin activity is one means by which cytoplasmic transport may be controlled during oocyte development. The eggs resulting from sqh1 clones, though smaller than normal, began development but exhibited an early defect in axial migration of cleavage nuclei towards the posterior pole of the embryo, in a similar manner to that seen in early cleavage eggs in which the actin cytoskeleton is disrupted. Thus both nurse cell dumping and axial migration require a maternally supplied myosin II.

Cardiac malformation in neonatal mice lacking connexin43

Gap junctions are made up of connexin proteins, which comprise a multigene family in mammals. Targeted mutagenesis of connexin43 (Cx43), one of the most prevalent connexin proteins, showed that its absence was compatible with survival of mouse embryos to term, even though mutant cell lines showed reduced dye coupling in vitro. However, mutant embryos died at birth, as a result of a failure in pulmonary gas exchange caused by a swelling and blockage of the right ventricular outflow tract from the heart. This finding suggests that Cx43 plays an essential role in heart development but that there is functional compensation among connexins in other parts of the developing fetus.

Detection of psychiatric morbidity in gynecology patients by two brief screening methods

Psychiatric morbidity was studied in 100 women attending gynecological outpatient and inpatient set-ups using two brief screening instruments: the General Health Questionnaire, 12 items, and the Present State Examination, ten short questions. Psychiatric morbidity was detected in 36% and was found to be higher in women with uterine prolapse and infections but not in those with menstrual irregularities (p < 0.001). The commonest psychiatric symptoms detected in this population were worrying (50%), aches and pains (51%), depression (50%) and disturbances of biological function (51%). The commonest diagnoses were neurotic depression (70%) and adjustment disorders (23%). The screening instruments used were found to be simple, sensitive, specific, with high identification indices and easy to administer.

Estrogen receptor mutations in tamoxifen-resistant breast cancer

Clinical resistance to antiestrogens like tamoxifen is a major problem in the treatment of hormone-dependent breast cancers. Since the estrogen receptor plays a central role in mediating the effects of estrogens and antiestrogens, we hypothesized that mutations in the estrogen receptor could be one mechanism by which breast tumors evolve from a hormone-dependent to a hormone-independent phenotype. The eight exons of the estrogen receptor complementary DNA from 20 tamoxifen-resistant and 20 tamoxifen-sensitive tumors were screened by Single Strand Conformation Polymorphism (SSCP), and the variant conformers were sequenced to identify the nucleotide changes. A 42-base pair replacement was found in exon 6 of a tamoxifen-resistant tumor. A single base pair deletion in exon 6 of a tamoxifen-resistant metastatic tumor but not in the primary tumor was detected in another case. If translated, both these mutations could generate truncated receptors with an intact DNA-binding domain and a defective hormone-binding domain that could constitutively activate transcription of previously estrogen-responsive genes. The remaining 18 of 20 tamoxifen-resistant tumors did not contain mutations in any of the 8 exons of the estrogen receptor complementary DNA. These results suggest that mutations in the estrogen receptor occur at a low frequency and do not account for most estrogen-independent, tamoxifen-resistant breast tumors.

Invasive bladder cancer and uremia: dilemma in management

Invasive bladder cancer presenting with uremia is a rare phenomenon. The management of these sick patients becomes problematic since one does not know how aggressive the treatment should be and what possible outcome to expect. In this retrospective review of 117 patients with invasive bladder cancer we describe 8 patients with uremia, and discuss our management strategy and prognosis.

Disposition of salmeterol xinafoate in laboratory animals and humans

The disposition of [14C]salmeterol xinafoate, a new inhaled beta 2-adrenoceptor agonist with both bronchodilator and antiinflammatory activity, has been studied in laboratory animals and humans following intravenous and oral administration. [14C]Salmeterol was rapidly absorbed in animal species and humans with Cmax observed within 2 hr. Cmax was similar for normalized oral dose level in mice, rats, and rabbits. In dogs, Cmax was higher and reflected the greater oral bioavailability in this species. The plasma t1/2, after intravenous administration, was 5 hr in rats and 2 hr in dogs. The volume of distribution of salmeterol was significantly greater than total body water in both rats (40 liters/kg) and dogs (6 liters/kg) and indicated high tissue uptake of the compound. Plasma clearance was high in rats (95 ml/min/kg) and dogs (30 ml/min/kg). Radioactive drug-related material was widely distributed throughout body tissues in rats. The highest concentrations were present in kidney, liver, gastrointestinal tract, pituitary, lung, heart, and bone marrow. Transfer of radioactive drug-related material across the placental barrier or into milk, studied in rats, was low. In all species the majority of an oral or intravenous dose (55-75%) was excreted in feces. Biliary excretion in rats and dogs accounted for 53% (0-27 hr) and 40% (0-8 hr) of an oral dose, respectively, indicating good absorption across the gastrointestinal tract. Enterohepatic circulation was significant in rats. Salmeterol was cleared predominantly by metabolism in animals and humans.(ABSTRACT TRUNCATED AT 250 WORDS)

Hysteroscopic assessment of abnormal uterine bleeding in users of the intrauterine contraceptive device

Sixty users of the IUD who complained of abnormal menstrual blood loss were evaluated by hysteroscopy, and the findings were compared with a matched group who had this investigation for "missing strings". Submucous fibroids and endometritis were more frequent in the study group whereas malposition of the IUD was commoner in the controls (p < 0.05).

Surgery for post-hysterectomy vaginal prolapse

Nine cases treated by surgery for post-hysterectomy vaginal prolapse are reviewed. The mean time between presentation and the antecedent hysterectomy was 12.8 years. Two patients who had abdominal sacral colpopexy alone developed recurrence of prolapse. Additional culdoplasty and colposuspension improved the cure rate but prolonged the mean operating time. Restoration of vaginal anatomy and function is best achieved with the combined operation.

Diagnostic hysteroscopy

Diagnostic hysteroscopy was performed on 100 patients. The most frequent indication was abnormal uterine bleeding. In premenopausal women, submucous fibroids were the main findings and in post-menopausal women, 59 per cent had an atrophic endometrium. Precise localization of the missing intrauterine contraceptive devices was achieved in all cases. Hysteroscopy improved diagnostic accuracy and reduced the need for blind curettage.