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C Ross

Publications and source records attributed to C Ross.

At least 37 records · Page 2Linked to original sources
PubMed1998

Phylogenetic analysis of anthropoid relationships.

The relationships of anthropoids to other primates are currently debated, as are the relationships among early fossil anthropoids and crown anthropoids. To resolve these issues, data on 291 morphological characters were collected for 57 taxa of living and fossil primates and analyzed using PAUP and MacClade. The dental evidence provides weak support for the notion of an adapid origin for anthropoids, the cranial evidence supports the tarsier-anthropoid hypothesis, and the postcranial evidence supports a monophyletic Prosimii and a monophyletic Anthropoidea. Combining these data into a single data set produces almost universal support for a tarsier-anthropoid clade nested within omomyids. Eosimias and Afrotarsius are certainly members of this clade, and probably basal anthropoids, although the Shanghuang petrosal may not belong to Eosimias. The tree derived from the combined data set resembles the tree derived from the cranial data set rather than the larger dental data set. This may be attributable to relatively slower evolution in the cranial characters. The combined data set shows Anthropoidea to be monophyletic but the features traditionally held to be anthropoid synapomorphies are found to have evolved mosaically. Parapithecines are the sister taxon to crown anthropoids; qatraniines and oligopithecids are more distantly related sister taxa. There is support for a relationship of a Tarsius + Anthropoidea clade with either washakiines on Uintanius. These elements of tree topology remain fairly stable under different assumptions sets, but overall, tree topology is not robust. Previously divergent hypotheses regarding anthropoid relationships are attributable to the use of restricted data sets. This large data set enables the adapid-anthropoid hypothesis to be rejected, and unites Tarsius, Anthropoidea and Omomyiformes within a clade, Haplorhini. However, relationships among these three taxa cannot be convincingly resolved at present.

Animals↗
PubMed1998

Isolation of parvalbumin isotypes by preparative HPLC techniques.

Parvalbumins are highly stable Ca2+ binding proteins, present in large quantities in the sarcoplasmic reticulum in the white muscle of most lower vertebrates and fish. The properties of these proteins make them promising antigens for the use as a specific biomarker for fish species identification. Parvalbumin isotypes were isolated, on a preparative scale level, by use of size exclusion chromatography (SEC) and anion exchange HPLC. The utility of this technique, with regard to maximizing purified isotypes, is discussed.

Animals↗
PubMed1997

Increased in vivo antibody activity against interferon alpha, interleukin-1alpha, and interleukin-6 after high-dose Ig therapy.

High-avidity antibodies against interferon alpha (IFN alpha), interleukin-1alpha (IL-1alpha), and IL-6 have been demonstrated in preparations of normal human IgG, and in vivo modulation of these cytokines may therefore account for immunomodulatory and anti-inflammatory effects of high-dose intravenous IgG therapy. We have investigated the in vivo recovery and the effect on serum cytokine levels of antibodies to IFN alpha, IL-1alpha, and IL-6 infused with IgG preparations. Fifteen treatment series of 0.4 g IgG/kg/d were administered over 3 days to eight patients with autoimmune diseases. All IgG preparations contained variable amounts of antibodies binding to 125I-labeled human IFN alpha2A, -IL-1alpha, and -IL-6, and the contents of these molecules correlated with increased levels in serum anticytokine activities after IgG infusion. The infused anti-IL-1alpha antibody activity was fully recovered, whereas the recovery of anti-IFN alpha2A antibodies was significantly reduced. Serum antiviral activities were significantly reduced after IgG therapy (before, 0 to 5.6 IU/mL; after, 0 to 0.6 IU/mL). In contrast, enzyme-linked immunosorbent assay (ELISA) showed no significant reduction in the serum levels of IL-6 (before, 1 to 70 pg/mL; after, 2 to 55 pg/mL), and the levels of IL-1alpha were consistently below the detection limit (<30 pg/mL). In conclusion, increased levels of antibodies to IFN alpha2A, IL-1alpha, and IL-6 occurred in patients receiving IgG and this reduced the serum antiviral activity.

Adult↗
PubMed1997

alpha 1-adrenoceptor-mediated negative inotropy of adrenaline in rat myocardium.

1. The effect of alpha- and beta-adrenoceptor stimulation on isotonic contraction was investigated on right ventricular papillary muscles of the rat, stimulated at a rate of 0.5 Hz. 2. Adrenaline (0.5 microM) induced a slight but significant negative inotropic effect: shortening decreased from 0.137 +/- 0.058 to 0.122 +/- 0.059 muscle lengths (mean +/- S.D.; -11%, P < 0.0001) and maximum shortening velocity from 2.9 +/- 1.2 to 2.7 +/- 1.3 muscle lengths s-1 (-7%, P < 0.025). 3. The negative inotropic effect of adrenaline was enhanced after blocking the beta-adrenoceptors with 50 microM atenolol. On the other hand, exposure to adrenaline after blocking the alpha-adrenoceptors with 50 microM phentolamine resulted in an increase in shortening as well as in maximum shortening velocity. 4. Stimulation of the beta-adrenoceptors with 0.5 microM isoprenaline caused marked positive inotropic effects, whereas stimulation of the alpha 1-adrenoceptors with 0.5 microM phenylephrine regularly resulted in a long-lasting decrease in shortening and maximum shortening velocity. 5. 1,2-Dioctanoyl-sn-glycerol (1,2-DOG) and adrenaline induced an activation of protein kinase C (PKC) with translocation of this enzyme from the cytosol to the sarcolemma. 6. Activation of PKC with 10 microM 1,2-DOG and 0.5 microM adrenaline was accompanied by a decrease in shortening and maximum shortening velocity. Inhibition of PKC with 0.1 microM staurosporine abolished the negative inotropic effect of adrenaline. 7. From these results we conclude that a low dose of adrenaline stimulates not only beta-but also alpha-adrenoceptors and that the observed negative inotropic effect of adrenaline is mediated by alpha 1-adrenoceptors, linked to the diacylglycerol-PKC signal transduction pathway.

Animals↗
PubMed1997

Anthropoid origins.

Recent fossil discoveries have greatly increased our knowledge of the morphology and diversity of early Anthropoidea, the suborder to which humans belong. Phylogenetic analysis of Recent and fossil taxa supports the hypotheses that a haplorhine-strepsirrhine dichotomy existed at least at the time of the earliest record of fossil primates (earliest Eocene) and that eosimiids (middle Eocene, China) are primitive anthropoids. Functional analysis suggests that stem haplorhines were small, nocturnal, arboreal, visually oriented insectivore-frugivores with a scurrying-leaping locomotion. A change from nocturnality to diurnality was the fundamental adaptive shift that occurred at the base of the tarsier-eosimiid-anthropoid clade. Stem anthropoids remained small diurnal arborealists but adopted locomotor patterns with more arboreal quadrupedalism and less leaping. A shift to a more herbivorous diet occurred in several anthropoid lineages.

Adaptation, Biological↗
PubMed1997

A comparison of osteoarthritis and rheumatoid arthritis: diagnosis and treatment.

Arthritis is one of the most common chronic illnesses managed in primary care. Osteoarthritis and rheumatoid arthritis are two common types the provider must distinguish between in terms of diagnosis and treatment. Osteoarthritis, the most common form, typically occurs in people more than 60 years of age and involves cartilage destruction. Signs and symptoms are local and include cool, bony joints and arthralgia that worsens with weight bearing. Treatment includes acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), exercise, and joint arthroplasty in severe cases. Rheumatoid arthritis is a systemic disease that results in symmetrical joint inflammation along with constitutional symptoms such as fatigue and depression. Current treatment recommendations include early use of disease modifying anti-rheumatic drugs along with NSAIDs. The key to arthritis management is early diagnosis and treatment to prevent further joint destruction and maximize functional ability.

Aged↗
PubMed1997

Testosterone replacement in older hypogonadal men: a 12-month randomized controlled trial.

A decline in testicular function is recognized as a common occurrence in older men. However data are sparse regarding the effects of hypogonadism on age-associated physical and cognitive declines. This study was undertaken to examine the year-long effects of testosterone administration in this patient population. Fifteen hypogonadal men (mean age 68 +/- 6 yr) were randomly assigned to receive a placebo, and 17 hypogonadal men (mean age 65 +/- 7 yr) were randomly assigned to receive testosterone. Hypogonadism was defined as a bioavailable testosterone <60 ng/dL. The men received injections of placebo or 200 mg testosterone cypionate biweekly for 12 months. The main outcomes measured included grip strength, hemoglobin, prostate-specific antigen, leptin, and memory. Testosterone improved bilateral grip strength (P < 0.05 by ANOVA) and increased hemoglobin (P < 0.001 by ANOVA). The men assigned to testosterone had greater decreases in leptin than those assigned to the control group (mean +/- SEM: -2.0 +/- 0.9 ng/dL vs. 0.8 +/- 0.7 ng/dL; P < 0.02). There were no significant changes in prostate-specific antigen or memory. Three subjects receiving placebo and seven subjects receiving testosterone withdrew from the study. Three of those seven withdrew because of an abnormal elevation in hematocrit. Testosterone supplementation improved strength, increased hemoglobin, and lowered leptin levels in older hypogonadal men. Testosterone may have a role in the treatment of frailty in males with hypogonadism; however, older men receiving testosterone must be carefully monitored because of its potential risks.

Aged↗
PubMed1997

Given diabetes, is fat better than thin?

OBJECTIVE: To evaluate the association between BMI and mortality in women and men with type II diabetes. RESEARCH DESIGN AND METHODS: Fasting plasma glucose (FPG), height and weight measurements, and medical history were obtained from 4,483 community-dwelling adults, aged 40-79 years, in 1972-1974. A total of 373 persons with either a history of diabetes or FPG > or = 7.77 mmol/l were studied. Subjects were grouped into four sex-specific weight categories based on U.S. population data. Vital status after 14 years was known for 99.9% of the patients studied. Cox models were used to assess relative survival by weight category. RESULTS: Diabetic men and women of average weight had the lowest mortality. A J-shaped relative risk curve by weight category was found, with a poorer survival rate for those who were thin, overweight, or obese. This effect was not explained by early mortality or cigarette smoking. CONCLUSIONS: Being thin may not provide a mortality benefit for diabetic men and women. Average weight appears to be desirable.

Adult↗
PubMed1997

Report of the Northern California Conference for Guidelines on Aid-in-Dying: definitions, differences, convergences, conclusions.

In September 1996, the Stanford University Center for Biomedical Ethics convened a conference entitled "Comprehensive Care of the Terminally Ill: The Northern California Consensus Development Conference for Guidelines on Aid-in-Dying." The regionally based, multidisciplinary conference gathered people from a variety of disciplines and diverse perspectives on physician aid-in-dying. This report documents important points of convergence, disagreement, and uncertainty that emerged from the conference and provides commentary on crucial issues: the definition of terminal illness, ensuring adequate palliative care, psychiatric challenges, coping with family pressures, the doctor-patient relationship, the managed care context, the role of ethics committees, and institutional challenges. Should physician aid-in-dying become a legal practice in California, the report will provide guidance to health care organizations, health professionals, and public policy officials engaged in local or state guideline or policy development.

California↗
PubMed1997

Teaching cardiopulmonary resuscitation in a developing country: using Nicaragua as a model.

This article discusses the experience of teaching cardiopulmonary resuscitation (CPR) within a cross-cultural context. The purpose of the two CPR programs, to both the physicians and nurses at the Ministry of Health and the faculty at the UPOLI School of Nursing, were to "train the trainer" using these health professionals to become trainers in the area of CPR.

Cardiopulmonary Resuscitation↗
PubMed1996

Complexes of HIV-1 reverse transcriptase with inhibitors of the HEPT series reveal conformational changes relevant to the design of potent non-nucleoside inhibitors.

Crystal structures of HIV-1 reverse transcriptase (RT) complexed with a range of chemically diverse non-nucleoside inhibitors (NNIs) have shown a single pocket in which the inhibitors bind and details of the inhibitor-protein interactions. To delineate the structural requirements for an effective inhibitor, we have determined the structures of three closely related NNIs which vary widely in their potencies. Crystal structures of HIV-1 RT complexed with two very potent inhibitors, MKC-442 and TNK-651, at 2.55 angstroms resolution complement our previous analysis of the complex with the less effective inhibitor, HEPT. These structures reveal conformational changes which correlate with changes in potency. We suggest that a major determinant of increased potency in the analogues of HEPT is an improved interaction between residue Tyr181 in the protein and the 6-benzyl ring of the inhibitors which stabilizes the structure of the complex. This arises through a conformational switching of the protein structure triggered by the steric bulk of the 5-substituent of the inhibitor pyrimidine ring.

Antiviral Agents↗
PubMed1996

Surgical management of brachioaxillary-subclavian vein occlusion.

OBJECTIVE: The possibility of using RING PTFE graft as venous bypass to preserve arteriovenous graft function and reduce upper extremity swelling. METHODS: Twenty-two patients with stenosis/occlusion of the brachial-axillary-subclavian vein segment in haemodialysis patients (n = 19) and patients with penetration injury (n = 3) who were not candidates for balloon angioplasty were treated with ring PTFE venous bypass in renal patients and jugular to axillary vein transposition for trauma patients and followed for 10-87 months (mean 31) using venography, Doppler analysis and Duplex scanning. RESULTS: There was no death or neurologic deficit resulting from the venous bypass. Resolution of swelling occurred in 8-48 h. 19/22 (86%) of the bypasses and 3/3 transpositions remained patent after a mean follow-up of 31 months (10-87) months. The attrition was due to AV graft occlusion (n = 2) and infection requiring graft removal (n = 1). CONCLUSIONS: Ring PTFE graft is an acceptable venous bypass for brachial-axillary-subclavian stenosis/occlusion to reduce arm swelling and preserve the function of AV grafts in patients with lesions not amendable with balloon angioplasty or thrombolytic therapy. Jugular-axillary transposition is inappropriate for renal patients.

Adult↗
PubMed1996

Nurses performing embryo transfer: successful outcome of in-vitro fertilization.

This prospective study demonstrates the feasibility and outcome of embryo transfer performed by nursing staff with medical cover available. Of 771 patients who had embryo transfer, 679 (88%) had their embryo transfer performed by a nurse. In 92 cases (12%) a doctor performed the embryo transfer, either as the first operator, or having been brought in to assist the nurse who experienced difficulty. The pregnancies per transfer for nurse transfer was 246/679 (36%) and where a doctor performed the transfer 20/68 (29%). These data show a high comparable success rate when a nurse performed the embryo transfer, and a low incidence of direct medical involvement.

Embryo Transfer↗
PubMed1996

Risk factors for nephropathy and cardiovascular disease in diabetic Northern Minnesota American Indians.

Although complications of diabetes are common among Southwest American Indians, little is known about diabetes and associated risk factors for nephropathy and cardiovascular disease in other genetically distinct tribes. We conducted a retrospective analysis of 665 diabetic patients at two Chippewa Indian reservations in northern Minnesota to evaluate the prevalence of risk factors for diabetic nephropathy and cardiovascular disease. In 79 patients, a more detailed study was carried out, including an assessment of renal function and urinary albumin excretion (UAE). The overall prevalences of proteinuria and hypertension were 47.9% and 62.6%, respectively. Proteinuria was observed more often in hypertensive than in non-hypertensive patients (55.2% vs 44.4%, p < 0.05), and in patients with diabetes for longer than 10 years (57% vs 40% for diabetes less than 10 years, p < 0.05). Although hypercholesterolemia (total cholesterol > or = 200 mg/dl) was observed in 54% of patients, there was no relationship between hypercholesterolemia and proteinuria. In the 79 patients studied in more detail, UAE was greater in hypertensive patients compared to non-hypertensive patients (606 +/- 15600 mg/24h vs 101 +/- 157 mg/24 h, p < 0.05), and in patients with diabetes for 10 years or longer compared to patients in the first decade of disease (748 +/- 1732 mg/24 h vs 96 +/- 171 mg/24 h, p < 0.05). Hypercholesterolemia and elevated LDL-cholesterol (> 130 mg/dl) were observed in 56% and 49% of patients, respectively, but were not associated with increased UAE. In contrast, hypertriglyceridemia (> 250 mg/dl) was associated with an elevated UAE (932 +/- 2150 mg/24 h vs 245 +/- 735 mg/24h, p < 0.05). Increased lipoprotein(a) was found in patients with overt albuminuria. In summary, the prevalence of risk factors for diabetic nephropathy and associated cardiovascular disease is high in Chippewa American Indians in northern Minnesota. Although detecting abnormal UAE may be useful in identifying high-risk patients who may benefit from early intervention, traditional risk factors such as hypercholesterolemia may not explain the risk associated with increased UAE.

Adolescent↗
PubMed1996

Cryptococcal meningitis in AIDS--need for early diagnosis.

Cryptococcal meningitis is the most common opportunistic fungal infection in patients with Acquired Immunodeficiency Syndrome (AIDS) contributing to the increased morbidity and mortality. This important infection in AIDS seems to be under diagnosed in India. We discuss the clinical features, laboratory diagnosis and therapy of seven cases of cryptococcal meningitis detected in our hospital. Diagnosis was established in all cases by identification of the fungus in cerebrospinal fluid (CSF) by India Ink preparation and positive fungal culture in CSF and/or Blood. Six patients were treated with Amphotericin B and Flucytosine. Two were cured and have not relapsed on suppressive therapy. Two died during treatment. Two were lost to follow up. All the three patients who died had positive fungal culture in blood and CSF. Presence of Cryptococcemia in Cryptococcal meningitis is an indicator of poor prognosis. A high index of clinical suspicion and routine mycological surveillance essential to identify this infection.

AIDS-Related Opportunistic Infections↗