Effect of Gibberellic Acid on the Radiation-stunted Seedlings of Maize

Summary

Maize seeds of the single cross WF 9 × 38?11 were irradiated with pile neutrons with doses ranging from 1 × 10¹² Np to 5 × 10¹⁴ Np and then treated with gibberellic acid (GA). In one set of experiments the seeds were soaked in GA for 24 hours and raised in sand. In another set they were sprouted in water, and seedlings with a 2–3 cm root-length were from then grown on in GA solution. It was evident from both these experiments that GA can reverse the stunting of seedlings caused by radiation.     

Clinical aspects of the AIDS dementia complex in relation to histopathological and immunohistochemical variables

To correlate cerebral histopathological and immunohistochemical changes in the neuroclinical features of the AIDS dementia complex (ADC), autopsy results of 28 ADC patients were related, in a retrospective analysis, to scores on a standardised neurological examination performed at neurologic onset. From a histopathological point of view, the cases were classified as follows: 9 cases of HIV leucoencephalopathy (HIVL; diffuse myelin damage and rare microglial nodules), 7 cases of HIV encephalitis (HIVE; several microglial nodules and no myelin damage) and 12 cases of mixed HIVL and HIVE (HIVL-E). The groups differed significantly with respect to symptoms and CD4 count at neurologic onset, survival and neurological impairment. Immunohistochemically, the interstitial component (p24-positive cells scattered singly within the white matter) was significantly more prevalent in HIVL, and the micronodular component (p24-positive cells confined within microglial nodules) in HIVE. Neurological damage was worse in cases with a high prevalence of interstitial component or a low prevalence of micronodular component. HIVE, HIVL and HIVL-E are distinct clinical forms of ADC. Neurological impairment is related to white matter damage.     

Voltage-gated Ca2+ channel Ca(V)1.3 subunit expressed in the hair cell epithelium of the sacculus of the trout Oncorhynchus mykiss: cloning and comparison across vertebrate classes

Full-length sequence (>6.5 kb) has been determined for the Ca(V)1.3 pore-forming subunit of the voltage-gated Ca(2+) channel from the saccular hair cells of the rainbow trout (Oncorhynchus mykiss). Primary structure was obtained from overlapping PCR and cloned fragments, amplified by primers based on teleost, avian, and mammalian sources. Trout saccular Ca(V)1.3 was localized to hair cells, as evidenced by its isolation from an epithelial layer in which the hair cell is the only intact cell type. The predicted amino acid sequence of the trout hair cell Ca(V)1.3 is approximately 70% identical to the sequences of avian and mammalian Ca(V)1.3 subunits and shows L-type characteristics. The trout hair cell Ca(V)1.3 expresses a 26-aa insert in the I-II cytoplasmic loop (exon 9a) and a 10-aa insert in the IVS2-IVS3 cytoplasmic loop (exon 30a), neither of which is appreciably represented in trout brain. The exon 9a insert also occurs in hair cell organs of chick and rat, and appears as an exon in human genomic Ca(V)1.3 sequence (but not in the Ca(V)1.3 coding sequence expressed in human brain or pancreas). The exon 30a insert, although expressed in hair cells of chick as well as trout, does not appear in comparable rat or human tissues. Further, the IIIS2 region shows a splice choice (exon 22a) that is associated with the hair cell organs of trout, chick, and rat, but is not found in human genomic sequence. The elucidation of the primary structure of the voltage-gated Ca(2+) channel Ca(V)1.3 subunit from hair cells of the teleost, representing the lowest of the vertebrate classes, suggests a generality of sensory mechanism for Ca(V)1.3 across hair cell systems. In particular, the exon 9a insert of this channel appears to be the molecular feature most consistently associated with hair cells from fish to mammal, consonant with the hypothesis that the latter region may be a signature for the hair cell.     

Radioisotope blood volume measurement in uncontrolled retroperitoneal haemorrhage induced by a transfemoral iliac artery puncture

Standard-of-care, large volume crystalloid infusion, in the setting of uncontrolled bleeding, has been challenged and it is not known if fluid resuscitation increases retroperitoneal hemorrhage. We developed an experimental model of retroperitoneal haemorrhage to correlate haemodynamic and metabolic alterations with the blood volume loss. Anaesthetised, spontaneously breathing dogs (17.1+/-0.56 kg) were randomised to unilateral (UL, n=11) or bilateral (BL, n=11) iliac artery puncture, using a metallic device introduced through the femoral arteries and followed for 120 min. Initial and final blood volumes were determined using radioactive tracers, 99mTC and 51Cr, respectively. UL was associated with a stable arterial pressure and a moderate decrease in cardiac output and oxygen delivery. BL induced an abrupt and sustained decrease in mean arterial pressure, from 131.9+/-5.9 to 88.6+/-10.8 mmHg, and a much greater reduction in cardiac output, oxygen delivery and consumption than UL throughout the experiment. Total retroperitoneal blood loss after BL was 36.8+/-3.2 ml/kg, while after UL was 25.1+/-3.4 ml/kg (P=0.0262). We conclude that a transfemoral bilateral iliac artery puncture produces a clinically relevant model of uncontrolled retroperitoneal haemorrhage, with hypotension and low flow state, while a unilateral iliac artery lesion causes a compensated shock state.     

Use of the trans-abdominal rectus abdominis flap in sacrum surgery

The authors describe the method used to reconstruct the posterior wall of the pelvis using a flap taken from the rectus abdominis muscle after resection of the sacrum to treat neoplasm.