Biomedical subjects

D G Wood

Publications and source records attributed to D G Wood.

At least 19 recordsLinked to original sources

PubMed1990

Patellofemoral malalignment: a report of 68 cases treated by proximal and distal patellofemoral reconstruction.

A series of 68 knees were reviewed retrospectively at an average of 56 months following surgical treatment for patellar dislocation and subluxation. Fifty-three knees in 48 patients were assessed both subjectively by questionnaire and objectively by examination, and 15 knees were evaluated by questionnaire only. All cases were treated by a proximal and distal reconstruction as described by Trillat (1964). The surgery was performed by one surgeon (MC) and reviewed independently (DW). The results were excellent in 48 knees (71 per cent), good in 12 (17 per cent) and poor in 8 (12 per cent). In no patient had there been any further episodes of dislocation. We consider this a straightforward procedure producing consistent correction of patellofemoral instability with a low morbidity.

Adolescent↗

PubMed1990

Vertical transmission of human immunodeficiency virus is correlated with the absence of high-affinity/avidity maternal antibodies to the gp120 principal neutralizing domain.

Many, but not all, infants born to mothers infected with the human immunodeficiency virus (HIV) are infected in utero. We have now shown that mothers who have high-affinity/avidity antibodies directed toward the principal neutralizing domain (PND) of gp120 are less likely to transmit HIV to their children. An ELISA that preferentially measures the level of the biologically functioning, high-affinity/avidity antibodies against PND is described. In a retrospective study of 15 maternal/neonatal serum samples, the assay correctly identified the 4 uninfected and the 11 HIV-infected infants. Other clinical and laboratory parameters such as p24 antigen, phytohemagglutinin mitogenic index, and absolute surface antigen T4+ cell counts did not accurately predict HIV fetal transmission. In addition to introducing a promising diagnostic tool, this study provides the in vivo evidence that protective antibodies may prevent infection by HIV.

Amino Acid Sequence↗

PubMed1989

Selective alteration of constitutive hepatic cytochrome P-450 enzymes in the rat during parenteral hyperalimentation.

Decreased drug metabolism and hepatic cytochrome P-450 levels have been shown previously to occur in rats receiving total parenteral nutrition (TPN) compared to animals receiving the same hyperalimentation solution enterally (TEN). In the present studies, animals received a 7-day infusion of a 25% glucose-2.75% crystalline amino acid solution via a catheter in the jugular vein or stomach; hepatic microsomal levels of four major constitutive cytochromes P-450 were determined subsequently by immunoquantitation and correlated with metabolism of selected substrates biotransformed by these enzymes. TPN resulted in a marked decrease in apoprotein of two constitutive cytochromes P-450, P-450UT-A and P-450PCN-E, compared to TEN experiments (for P-450UT-A, 11.0 +/- 1.8 vs 44.7 +/- 6.5% of total cytochrome P-450 measured by CO-difference spectra, P greater than 0.001; for P-450PCN-E, 15.4 +/- 4.4 vs 30.2 +/- 7.6%, P less than 0.01), but apoprotein levels of two other constitutive cytochromes P-450, P-450PB-C and P-450UT-F, showed relatively little change. Concordant reductions in metabolism of benzphetamine, ethylmorphine and erythromycin were seen in TPN animals. While the mechanisms responsible for these selective changes in the synthesis and function of individual cytochromes P-450 remain to be elucidated, altered gene transcription due to differences in portal blood composition elicited by intravenous versus enteral feeding is a possible hypothesis. These studies also provide information which should be valuable in designing studies to probe further the clinical question of whether TPN induces significant alterations in human drug metabolism.

Animals↗

PubMed1988

Ovarian function in the elephant: luteinizing hormone and progesterone cycles in African and Asian elephants.

Serum samples were collected weekly for 3 yr from two female African elephants, for 18 mo from two other female African elephants, and for 2 yr from two female Asian elephants. Animals were not sedated at the time of blood collection. Ovarian cycles, characterized by changes in progesterone and immunoreactive luteinizing hormone (ILH) concentrations, averaged 15.9 +/- 0.6 wk (N = 25) for African females and 14.7 +/- 0.5 wk for Asian females (N = 10). The length of the active luteal phase averaged 10.0 +/- 0.3 wk for African elephants (range 8-14 wk) and 10.6 +/- 0.6 wk for Asian females (range 9-13 wk). Interluteal phases were 5.9 +/- 0.6 wk for African females and 4.2 +/- 0.5 wk for Asian females. One African female (Maliaca) had two extended interluteal phases, both occurring between the months of February and May. Excluding these two periods, there were no differences in the length of the ovarian cycle or the length of the luteal phase between species of elephant. Serum progesterone in both species ranged from less than 50 pg/ml to 933 pg/ml. Average progesterone concentrations during the luteal phase were significantly lower in African elephants compared with Asian elephants (328 +/- 13, N = 30 cycles vs. 456 +/- 23, N = 14 cycles; p less than 0.001). ILH ranged from nondetectable to 11.6 ng/ml. These data suggest that the length of the ovarian cycle in the African elephant is about 16 wk and confirm that the length of the ovarian cycle in the Asian elephant is about 15 wk.

Animals↗

PubMed1970