PubMed HealthSearch

Biomedical subjects

G S Ross

Publications and source records attributed to G S Ross.

14 recordsLinked to original sources

An ethylene-related cDNA from ripening apples.

We report the isolation of a ripening-related apple cDNA which is complementary to a mRNA which may be involved in ethylene production. Poly(A)+ RNA was extracted from cortical tissue of ripe apple fruit (Malus domestica Borkh cv. Golden Delicious) and a cDNA library constructed in the plasmid vector pSPORT. The library was screened with pTOM13, a tomato cDNA clone thought to code for ACC oxidase in that fruit. An apple cDNA clone (pAP4) was isolated and sequenced. The 1182 bp cDNA insert includes an open reading frame of 942 bp, and shows strong homology with reported tomato and avocado sequences, both at the nucleic acid and amino acid levels. The polypeptide has a calculated molecular mass of 35.4 kDa and a calculated pI of 5.15. In apple cortical tissue, expression of pAP4-complementary RNA increased with ethylene production by the fruit during ripening. Expression was also enhanced in both ethylene-treated and wounded fruit.

Amino Acid Sequence

Myocardial infarction associated with inappropriate use of topical cocaine as treatment for epistaxis.

A case of a 57-year-old man with hypertension and stable angina, on aspirin therapy, who was treated for epistaxis with intranasal cocaine, and who subsequently suffered a non-Q wave myocardial infarction is reported. Of note, the cocaine was administered in a manner which differs from that advocated in standard references. Specifically, intranasal packing soaked with 4% cocaine was left in place with continuous nasal mucous membrane contact over 5 to 6 hours. The authors speculate that myocardial infarction occurred on the basis of coronary artery spasm. This case should alert practitioners to myocardial ischemia occurring as a complication of the therapeutic use of intranasal cocaine for the treatment of epistaxis.

Administration, Intranasal

Clinical prediction of Pneumocystis pneumonia.

Pneumocystis carinii pneumonia is often difficult to diagnose in an ambulatory care setting. Previous reports have identified elements of the clinical history, physical examination, and clinical testing that are useful predictors of P carinii pneumonia. We analyzed published data on these predictors and measured them against methodologic standards for clinical prediction rules. Variables with high negative or positive predictive value for P carinii pneumonia, low error rates, or compelling biologic credibility were then selected to develop an untested clinical prediction rule for P carinii pneumonia. We suggest that dyspnea, oral lesions, chest roentgenographic examination, and pulse oximetry may be used to select patients requiring sputum testing and/or bronchoscopy for the diagnosis of P carinii pneumonia. The role of pulse oximetry in the diagnosis of P carinii pneumonia merits further study.

Dyspnea

An acquired hemorrhagic disorder from long-acting rodenticide ingestion.

A 62-year-old man who presented with gross hematuria was found to have a severe and prolonged coagulopathy. The workup involved mixing studies, which suggested an acquired factor deficiency, and specific factor assays, which demonstrated isolated defects in vitamin K-dependent factors. With vitamin K deficiency excluded, and serum warfarin levels undetectable, so-called superwarfarin ingestion was suspected. This diagnosis was subsequently proved by biochemical evidence (an increase in the serum vitamin K epoxide-vitamin K ratio) and compatible history. This case illustrates how a logical workup can lead to a diagnosis of superwarfarin ingestion, even without a history of such an ingestion. New serum assays for specific superwarfarins are also mentioned. This case report should increase clinicians' awareness of long-acting rodenticide ingestions.

4-Hydroxycoumarins

Investigation of bovine viral diarrhea virus infections in a range beef cattle herd.

Bovine viral diarrhea virus (BVDV) infections resulting in clinical disease developed in calves, despite vaccination of dams and high maternal BVDV antibody titers in calves. Eight persistently infected (PI) calves born to immunocompetent dams were identified in the herd. Neutralizing BVDV antibody titers of PI calves had decreased greatly by the time the calves were 1 to 2 months old. Antibody titers of PI calves decreased more rapidly than antibody titers of calves that were not PI. Reduced antibody titers in PI calves allowed detection of BVDV in serum specimens of all PI calves by the time they were 8 weeks old. Persistent infection in suspect calves was detectable serologically and was confirmed by virologic examination of serum specimens 4 months after weaning, when the calves were 9 months old. Growth rates were reduced in viremic calves.

Animals

Survival and outcome of infants weighing less than 800 grams at birth.

This study reports on two aspects of outcome in a sample of infants whose birth weights ranged from 500 to 799 gm. First, maternal and early neonatal variables were analyzed by means of stepwise logistic regression. Five-minute Apgar score and initial pH were the only variables that predicted mortality at p less than or equal to 0.05. Second, the surviving infants were examined at ages ranging from 17 months to 7 years. The majority (72%) had neurologic and/or developmental examinations in the suspect or abnormal range and required rehabilitation or early intervention services.

Body Constitution

Organ hypertrophy and responses of colon microbial populations of growing swine to high dietary protein.

Thirty-two castrated male crossbred growing pigs (average initial wt 26.9 kg) were used to determine the effect of a high level of dietary protein (37%) compared with a normal level of protein (15%) on enterobacteria and Campylobacter sp. inhabitation in the large intestine and on visceral organ hypertrophy and the interrelationships between these two factors. Pigs were kept in pairs (eight pens of two pigs/diet) and fed their respective diets and libitum. Eight pigs (two pens of two pigs fed each diet) were killed at wk 4, 8, 12 and 16 without fasting. Fecal samples were obtained every 2 wk from animals scheduled for necropsy at 16 wk, and colon contents were obtained from all pigs at necropsy; samples were enumerated individually for enterobacteria and Campylobacter sp. Weights of heart, lungs, liver, kidneys, perirenal fat and empty stomach, small intestine and large intestine were recorded at necropsy. Stomach, cecum and proximal colon were sectioned for histopathologic examination. Daily body weight gain was depressed by high dietary protein, but liver and kidneys were heavier in the high protein group than in controls at each time interval. Mild lymphoid hyperplasia of Peyer's patches in the small intestine in some pigs in both groups was indicative of antigenic stimulation but not of pathologic significance. There was no effect of diet on counts of enterobacteria or Campylobacter sp. in feces or colon contents during the 16-wk experiment. We conclude that the hypertrophic response of the tissues of growing pigs to high dietary protein is not the result of the presence of Campylobacter sp. or enterobacteria in the colon contents.

Animals

Transient global amnesia triggered by mild head trauma.

In 9 patients, aged 11 to 28 years, minor head injury triggered an amnesic attack grossly disproportionate to the degree of trauma. During these attacks, patients were unable to form new memories for 2 to 24 hours, had extensive retrograde amnesia, voiced repetitive queries and were disorientated for time, but were otherwise intact neurologically. We suggest that these episodes were attacks of transient global amnesia triggered by the mild blows to the head. We also suggest that they constitute a previously unrecognized variety of traumatic migraine.

Adolescent

The use of percent volume analysis in Coulter sizing of cells in gynecologic cytopathologic cell suspensions.

The Coulter Counter model TA II was evaluated as a gynecologic cytodiagnostic tool. The instrument produces particle size histograms as plots of percent volume versus particle volume in 16 channels with each channel corresponding to twice the volume of the next lower channel. Cell volume distributions were obtained using cell suspensions from patients with cervicitis, inflammation, dysplasia or carcinoma and were compared with those from normal subjects. Although this method is superior to other methods of volume distribution analysis, it does not satisfy the stringent requirements of a cervical cancer mass screening method.

Cell Count