Influence of glucose, alcohol and glycerol on galactose tolerance in man

Six volunteers were given 0.5 g galactose/kg body weight alone (A) or with 0.5 g glucose/kg (B) or with 0.5 g glycerol/kg body weight (C). Meals A and B were also given 15 min after ingestion of 300 mg ethanol/kg body weight. Glycerol did not influence the serum galactose response to galactose. Glucose reduced the serum galactose response as was expected. Administration of alcohol prior to a galactose test meal increased the mean area under the serum galactose response curve (p less than 0.01); when glucose was given with galactose after alcohol ingestion, the serum galactose response was significantly reduced (p less than 0.01) when compared to the serum galactose response to galactose after alcohol, but remained higher than after the galactose and glucose test meal. Glucose, therefore, can reduce the effect of alcohol on galactose levels but alcohol can abolish the effect of glucose on galactose metabolism.

The influence of straining maneuvers on the pressor response during isometric exercise

Experiments were performed to determine to what extent increments in esophageal and abdominal pressure would have on arterial blood pressure during fatiguing isometric exercise. Arterial blood pressure was measured during handgrip and leg isometric exercise performed with both a free and occluded circulation to active muscles. Handgrip contractions were exerted at 33 and 70% MVC (maximum voluntary contraction) by 4 volunteers in a sitting position and calf muscle contractions at 50 and 70% MVC with the subjects in a kneeling position. Esophageal pressure measured at the peak of inspirations did not change during either handgrip or leg contractions but peak expiratory pressures increased progressively during both handgrip and leg contractions as fatigue occurred. These increments were independent of the tensions of the isometric contractions exerted. Intra-abdominal pressures measured at the peak of either inspiration or expiration did not change during inspiration with handgrip contractions but increased during expiration. During leg exercise, intraabdominal pressures increased during both inspiration and expiration, reaching peak levels at fatigue. The arterial blood pressure also reached peak levels at fatigue, independent of circulatory occlusion and tension exerted, averaging 18.5-20 kPa (140-150 mm Hg) for both handgrip and leg contractions. While blood pressure returned to resting levels following exercise with a free circulation, it declined by only 2.7-3.8 kPa after leg and handgrip exercise, respectively, during circulatory occlusion. These results indicate that straining maneuvers contribute 3.5 to 7.8 kPa to the change in blood pressure depending on body position.

Restorative dentistry. Clinical applications

Restorative techniques for human teeth have been used and refined for centuries. Most of these techniques can be applied with few modifications to restore diseased or damaged teeth in animals. The results can be both functionally sound and cosmetically pleasing.

The Edgecombe County High Blood Pressure Control Program: the process of medical care and blood pressure control

As part of the Edgecombe County High Blood Pressure Control Program, a medical record review was conducted within a multispecialty private group practice in the county. The purposes of the review were to assess the relationship between the process of medical care and blood pressure control and to explore the variation in level and impact of medical care by race and sex. At the end of a three-year period, 41 percent of 628 hypertensive patients from the practice had uncontrolled diastolic blood pressure (DBP), as defined by Hypertension Detection and Follow-up Program criteria. The percentage of uncontrolled hypertensives ranged from 53 percent for black men to 34 percent for white women. Hypertensive patients whose physicians were more aggressive in their use of antihypertensive drug therapy were more likely to be controlled. The effect of the level of physician drug aggressiveness tended to be more pronounced for blacks than for whites. Differences by race in exposure to and efficacy of aggressive drug treatment may influence racial variation in blood pressure control.

Endodontics

It is known that pets with broken teeth or teeth with other diseases of the pulp suffer considerable pain and frequent infection. To ignore these problem teeth would not only be inhumane, it would risk chronic infection, abscessation, and tooth loss. Although extraction of these teeth is sometimes necessary, the procedure is often difficult to perform and painful for the animal. The resultant tooth loss is cosmetically displeasing and, frequently, there is compromise in function. The endodontic treatment of these teeth, on the other hand, is relatively easy to perform. It almost always results in immediate cessation of pain and will usually allow the tooth to remain functional for the lifetime of the pet.

Feline dental disease

Periodontal disease and chronic gingivitis/stomatitis are the most common feline dental diseases. With routine dental care and increased emphasis on home oral hygiene, these diseases can be controlled. Cats can be seen with a number of other dental disorders, and improved treatment methods such as restorations of early subgingival resorptive lesions, endodontic therapy, and orthodontic therapy can be performed successfully. More study and research are necessary about the gingivitis/stomatitis syndrome and subgingival resorptive lesions so that improved prevention and treatment recommendations can be made.

Cyclical gonadotrophin and progesterone secretion in women with minimal endometriosis

Concentrations of LH, FSH, oestradiol (E) and progesterone (P) were measured in serum of 12 women with minimal endometriosis and otherwise unexplained infertility. Values were compared with those on corresponding days relative to the pre-ovulatory LH peak (Day 0) in six fertile women. Three women exhibited cycle profiles of LH, FSH, E and P indistinguishable from those in the control group. In the remaining nine women cycle profiles for FSH and follicular phase profiles for LH were normal but eight exhibited a delay in P secretion and reduced total P output. LH concentrations were elevated during the early luteal phase in five subjects, two of whom had a second LH surge. These data suggest that luteal dysfunction and abnormal secretory patterns for LH may be contributory to infertility associated with endometriosis.

The value of hepatic ultrasound and biochemical liver tests in screening for liver metastases

The records of 92 patients with a known diagnosis of extrahepatic cancer who had undergone hepatic ultrasound, biochemical liver tests (alkaline phosphatase, SGOT, lactic dehydrogenase, and bilirubin levels), and subsequent liver biopsy or autopsy within a 6-week period were reviewed. The sensitivity, specificity, and accuracy of the ultrasound and biochemical tests in the detection of metastatic liver disease were calculated. Although there was no significant difference in the sensitivity of either examination, the ultrasound demonstrated higher specificity and accuracy than the biochemical liver tests. The high sensitivity of hepatic ultrasound prevailed even in patients with normal biochemical liver tests. The sensitivity of hepatic ultrasound was significantly lower in patients with lymphoma compared with patients with colorectal cancer (50% v 100%, P less than .05). Notable incidental extrahepatic findings were reported in 25% of the ultrasound examinations. In institutions skilled in sonography, hepatic ultrasound may be a superior tool in the detection of liver metastases in most solid tumors, excluding lymphoma, and offers the additional advantage of simultaneous biliary tract and perihepatic visualization.

Extracellular proteolysis: developmentally regulated activity during chick spinal cord histogenesis

The present study was performed to identify at which stages during spinal cord histogenesis the extracellular proteolysis (i.e. the plasmin-generating system) is expressed by the developing tissue. We report that the embryonic chick spinal cord in the course of its histogenesis produces the protease, plasminogen activator. Specific activity of plasminogen activator in the developing embryo was monitored daily, in whole cords (from day 4 until hatching) and in the ventral and dorsal halves of the cord (6-17 days) and was biochemically determined by the fibrinolytic assay. The enzyme-specific activity of the developing cord was found to be very low at early embryonic stages when neuroblasts proliferate and it is markedly enhanced (14-fold at its maximal level) at later stages when the neurons are postmitotic and only the glial cells proliferate. The pattern of plasminogen activator specific activities does not remain at a constant level: it appears to be developmentally regulated, since it is decreased and enhanced during 3 temporal stages of the spinal cord histogenesis. These coincide with the stages when a transient increase in cell proliferation, presumably of glia, was monitored as determined daily by the spinal cord DNA content (microgram DNA/mg protein). Furthermore, on days 7-9 of embryonic age, the two halves of the cord differ in their plasminogen activator specific activities; activity levels of the ventral halves were found to be higher than their dorsal counterparts with significant difference on day 7. These correspond with the well-established differentiation gradient in the ventral-to-dorsal axis of the cord.(ABSTRACT TRUNCATED AT 250 WORDS)

Metaphyseal dysostosis and congenital nystagmus in a male infant with the fragile X syndrome

A 14-month-old male with congenital nystagmus, sparse scalp hair, protuberant ears, developmental delay, and radiologic manifestations of mild metaphyseal dysostosis was coincidentally found to have the fra(X) chromosome in 67% of analyzed metaphases. This observation underscores the need for fra(X) analyses in children with developmental deficit of unknown cause.

Sperm survival studies in peritoneal fluid from infertile women with endometriosis and unexplained infertility

Peritoneal fluid (PF) volume and sperm survival (motility and velocity) were studied in PF from women with unexplained infertility, infertile women with endometriosis and fertile women without endometriosis using a laser light scattering technique. PF volume was significantly larger in the group of women with unexplained infertility (P less than 0.025) and in infertile women with endometriosis (P less than 0.003) when compared with fertile women. There was a significant reduction in the percentage motile sperm in women with unexplained infertility (P less than 0.001) and in infertile women with endometriosis when compared with fertile women (P less than 0.001). In infertile women with endometriosis a positive correlation was observed between peritoneal fluid volume and reduction in the percentage of motile sperms (P less than 0.01).

Changes in isometric function following rhythmic exercise

Seven male subjects exercised for 1, 3, 10 and 20 min on a cycle ergometer at 20, 60 and 80% VO2max, and then held to fatigue a sustained contraction of the quadriceps at 40% maximal voluntary contraction in order to determine what influence various levels of dynamic exercise would have on isometric function of the same group of muscles. Muscle temperature was measured before and within 15 s of the completion of the cycling to determine whether changes in muscle temperature might influence the subsequent isometric performance. Isometric endurance was shorter as the severity of the cycling increased beyond 20% VO2max, and as the duration of cycling increased up to 10 min. There were discrete linear relationships between muscle temperature and isometric endurance associated with cycling at 60% and 80% VO2max. There was a direct inverse relationship between quadriceps strength after cycling and muscle temperature, yet a significant reduction in strength occurred only after cycling at 80% VO2max. These results suggest that the encroachment on endurance and strength are controlled by different mechanisms. The heart rates during the isometric contractions were dependent on the preceding rhythmic exercise and decreased after exercise at 60 or 80% VO2max. In contrast, the blood pressure always increased during the isometric contractions, reaching similar values at the point of fatigue, regardless of the severity of the previous rhythmic exercise. These data provide additional evidence that separate mechanisms control changes in heart rate and blood pressure.

Sympathetic control of the forearm blood flow in man during brief isometric contractions

Experiments were performed to assess the possible neurally mediated constriction in active skeletal muscle during isometric hand-grip contractions. Forearm blood flow was measured by venous occlusion plethysmography on 5 volunteers who exerted a series of repeated contractions of 4 s duration every 12 s at 60% of their maximum strength of fatigue. The blood flows increased initially, but then remained constant at 20-24 ml X min(-1) X 100 ml(-1) throughout the exercise even though mean arterial blood pressure reached 21-23 kPa (160-170 mm Hg). When the same exercise was performed after arterial infusion of phentolamine, forearm blood flow increased steadily to near maximal levels of 38.7 +/- 1.4 ml X min(-1) X 100 ml(-1). Venous catecholamines, principally norepinephrine, increased throughout exercise, reaching peak values of 983 +/- 258 pg X ml(-1) at fatigue. Of the vasoactive substances measured, the concentration of K+ and osmolarity in venous plasma also increased initially and reached a steady-state during the exercise but ATP increased steadily throughout the exercise. These data indicate a continually increasing alpha-adrenergic constriction to the vascular beds in active muscles in the human forearm during isometric exercise, that is only partially counteracted by vasoactive metabolites.

Effect of clonidine and naloxone on the pressor response during contraction of cat hind-limb muscles

The possible involvement of an adrenergic-endorphin system in the mediation of the pressor response to isometric muscular contraction was studied in cats. Fatiguing contractions of the gastrocnemius and plantaris muscles caused an increase in the mean arterial blood pressure by 35 to 70 mmHg. Intravenous infusion (30 micrograms X kg-1) as well as intracisternal injection (2.5 micrograms) of clonidine-HCl eliminated the pressor response to muscular contraction. In both sets of experiments, the mean blood pressure remained at the resting level throughout the duration of the isometric contraction. Injection of naloxone (0.5 mumol X litre-1) into the cisterna magna did not alter the resting blood pressure and did not affect the rise in mean arterial pressure during muscle contractions. Intracisternal injection of naloxone (0.5 mumol X litre-1) prior to an intracisternal injection of clonidine (2.5 micrograms) did not alter the resting blood pressure but effectively antagonised the anti-pressor effects of clonidine during fatiguing isometric contractions. These data may indicate that activation of muscle "ergoreceptor" afferents (group III and IV fibres) during muscular contraction may cause an increase in the arterial blood pressure by interfering with an inhibitory adrenergic-endorphinergic pathway in the brainstem.

Anaphylatoxin C5a modulation of an alpha-adrenergic receptor system in the rat hypothalamus

C5a anaphylatoxin injected via implanted cannulae into the perifornical region of the hypothalamus stimulated eating in sated rats. C5a also attenuated carbamyl choline-induced drinking, and carbamyl choline inhibited C5a-induced eating, a mutual inhibition characteristic of the adrenergic-cholinergic interactions at this site. The increased food intake induced by C5a was also reversed by phentolamine, an alpha-adrenergic antagonist. Granulocytes infiltrating as a result of C5a-mediated leukotaxis did not arrive at the site in time to influence C5a activity. We propose that C5a in some way activates an alpha-adrenergic receptor system in the hypothalamus, and that anaphylatoxins could mediate neuropsychiatric symptoms sometimes associated with immune complex diseases affecting the central nervous system.

Effect of immune complex-forming reactants on catecholamine-modulated behaviors in the rat hypothalamus

Injection of immune complex-forming reactants via implanted cannulae to the perifornical hypothalamus stimulated eating in sated rats and increased the eating response to exogenous norepinephrine (NE). Immune complex-induced eating was not seen after carbamyl choline injection, and immune complex treatment had no effect on water intake under any of the test conditions. The effects of immune complex activity occurred only 6 hours after administration, a time associated with heavy polymorphonuclear leukocyte infiltration of the cannula site. Immune complex activity mimics that following NE injection of this site. Because the immune complex-forming reactants are not specific to any neural antigen, we propose that their effects are indirectly mediated by anaphylatoxins produced by activation of the complement cascade.

The Edgecombe County High Blood Pressure Control Program: III. Social support, social stressors, and treatment dropout

In a hypertension prevalence survey of a stratified random sample of 1,000 households, 2,030 adults (aged 18 years and over) were interviewed and information on psychosocial variables collected. Among 359 hypertensives, there was a consistent relationship between indicators of difficulty in the social environment and dropout from treatment in women. Compared to those who remained in treatment, women who dropped out can be characterized as having less social support on the job, having less perceived spouse approval (if married), having a lower level of perceived access to supportive resources, and being more likely to report feeling pushed most or all of the time if they are homemakers. Relationships between indicators of social support and dropout from treatment in men were found only with support on the job, and for White men, with perceived friend approval.

Supports, stressors, and depressive symptoms in low-income mothers of young children

We investigated the association of social supports and stresses with depressive symptoms in a sample of 111 predominantly low-income mothers of young children. The prevalence of high depressive symptoms, as measured by the Center for Epidemiologic Studies--Depression Scale (CES-D), was 48 per cent. Among unmarried women, everyday stressors were strongly associated with depressive symptoms, while life events were weakly related. Associations between these variables were not found for married women. Comparing the relative importance of two different types of support--the quality of primary intimate relationships, and the social network--only the quality of the husband-intimate relationship was associated with CES-D scores among married women, whereas the social network demonstrated a moderate, inverse association with CES-D scores among unemployed women.

An examination of predictor variables for child compliance and noncompliance

The purpose of this study was to examine the antecedents of child compliance and noncompliance. Both maternal and child behaviors served as predictors. Fifty-six clinic-referred children and their mothers served as subjects. Data were collected in the home setting by independent observers. Four multiple regression analyses were performed. The results indicated that the behavior immediately preceding child compliance or noncompliance typically was the best predictor. Furthermore, the antecedents for child compliance and noncompliance differed. For maternal antecedents, the type of command that served as the best predictor for child compliance and noncompliance differed; however, the final predictor equation was similar for the two types of child behaviors. For child antecedents, compliance was best predicted by compliance and noncompliance was best predicted by noncompliance. The results were discussed in terms of Patterson's coercion hypothesis.

The Edgecombe County (NC) High Blood Pressure Control Program: II. Barriers to the use of medical care among hypertensives

As the initial step in a five-year project to improve control of high blood pressure in Edgecombe County, North Carolina, a survey was conducted in 1980 to determine the prevalence of hypertension and to identify factors which might constitute barriers to the use of medical care by hypertensives. This report summarizes the findings for the 539 hypertensives identified through the baseline survey. In general, Black hypertensives reported more access problems than Whites. Within race, however, males and females differed very little on selected measures of potential access to medical care. Among women, lower scores on potential access were strongly associated with being untreated, whereas for men, concerns about the safety of anti-hypertensive drug therapy were associated with being unaware. On a summary measure of the actual use of medical care in response to symptoms, both male and female treated hypertensives scored higher than their untreated counterparts. The implications of these and other findings for community-based blood pressure control activities are discussed.

Valproic acid-induced hyperammonemia in mentally retarded adults

All individuals receiving valproic acid therapy in an institution for the mentally retarded were evaluated for hyperammonemia. Of these 19 adults, 6 had persistent and 5 others had intermittent hyperammonemia. The hyperammonemic patients were asymptomatic, except that 2 had occasional lethargy. Hyperammonemia was detected more often in younger adults and in those treated with multiple anticonvulsants, especially phenytoin. Valproate-induced hyperammonemia is probably the result of depletion of mitochondrial acetyl CoA and decreased production of N-acetylglutamate, the obligatory activator of the first enzyme of the urea cycle, carbamyl phosphate synthetase I. Anticonvulsant-mediated microsomal enzyme induction may also contribute.

The Edgecombe County High Blood Pressure Control Program: I. Correlates of uncontrolled hypertension at baseline

To guide the planning of a multifacetted hypertension control program in Edgecombe County, North Carolina, a baseline survey of a stratified (by township) random sample of 1,000 households was conducted. All adults (greater than or equal to 18 years) were interviewed and had their blood pressures (BP) measured. Five hundred thirty-nine individuals, 27 per cent of the survey population, had diastolic BP greater than or equal to 90 mm Hg or were receiving anti-hypertensive drug therapy. The 539 hypertensives were divided into seven subgroups reflecting successive stages in the control of hypertension based on the awareness, treatment, and control of their hypertension. Unaware hypertensives were further subdivided into three groups according to the recency of their last BP check, and those aware but untreated were subdivided by whether they had previously received treatment. The seven subgroups of hypertensives were compared, separately for women and men, with respect to sociodemographic characteristics, health behaviors, and health status. In general, the progression from undetected hypertension to treatment and control appeared to be associated with being older, female, and White. This progression was further associated with greater educational levels and higher family incomes among women and increasing self-reported morbidity among men. The implications for intervention of these and other described associations are discussed.

Nurses with doctoral degrees: education and employment characteristics

Selected education and employment characteristics of nurses with doctorates were examined. Data were obtained in late 1979 and 1980 about three time periods in the 1,964 respondents' careers: (a) doctoral study, (b) first position, and (c) current position if different from first position. Of the nurses studied, 76% completed doctoral programs in the 1970s. Education was the major field of study most frequently reported, followed by social/behavioral sciences and nursing; federal monies were the major source of financial support. Nurses with doctorates were hired in their first position primarily for teaching in baccalaureate and higher degree programs in nursing with a sizable shift to administrative roles in academia among those reporting current positions different from first positions, Only 6% to 8% of doctorally prepared nurses were hired primarily for the conduct of research in either first or current position.

Psychopharmacological activity of anaphylatoxin C3a in rat hypothalamus

C3a anaphylatoxin injected into the perifornical hypothalamic region of sated rats increased the eating response to norepinephrine and the drinking response to carbamyl choline but had no effect on food or water intake in sated, saline control animals. This potentiation of drug-stimulated intakes was reversible by intrahypothalamic injection of catecholamine receptor antagonists haloperidol and phentolamine. We propose that C3a acts as a catecholamine agonist in the central nervous system. The results suggest that C3a may play a role in mediating the neuropsychiatric manifestations associated with immune complex formation or deposition in the central nervous system.

Possible source of adenosine triphosphate released from rat myocytes in response to hypoxia and acidosis

Ventricular cells from adult rats were isolated enzymatically and used as a model system for determining what factors affect the release of adenosine triphosphate (ATP) from myocardial cells. The enzyme systems used to isolate cells were trypsin:collagenase; hyaluronidase:collagenase and dispase:collagenase. Adenosine triphosphate was released in greater amounts in response to hypoxia from cells freed by each of the enzymatic procedures. This occurred while the intracellular concentration of ATP remained constant. Experiments were then performed to determine whether the conditions that occur during myocardial ischaemia or hypoxia altered the release of ATP. Cells suspended in either oxygenated or anoxic buffer at a pH of 6.8 released a significantly lower amount of ATP than cells suspended in either condition at pH 7.4. To test the possibility that ATP was released from nucleotide-protein-Ca2+ complexes located in the sarcolemma, artificial disruption of these structures was carried out. Incubation of oxygenated cells with the chelating agent, ethyleneglycol-bis (B-aminoethyl ether)-N, N-tetraacetic acid (EGTA), stimulated the release of ATP in a hyperbolic relationship while incubation of anoxic cells with ethylenediamine tetraacetate (EDTA) stimulated the release of ATP in such a way that the pattern of release followed a sigmoid response with maximal amounts of ATP, 995 +/- 55 pmol.mg-1 protein, occurring in the presence of 0.1 to 2.0 mmol.litre-1 EDTA. By incubating cells with radioactive EDTA, there was no indication that EDTA entered the cells. No release of ATP above control levels occurred when EDTA was chelated with Ca2+ before being applied to isolated cells. These data suggest that the source of ATP found extracellularly may have been nucleotide-protein-Ca2+ complexes located in the sarcolemma, and further support the role of ATP as a coronary vasodilator during hypoxic conditions.

The influence of glucose on serum galactose levels in man

To investigate the effect of simultaneous glucose and galactose administration on serum galactose levels in man, volunteers were given a standard galactose meal of 0.5 g galactose/kg BW alone and with various body weight related glucose loads and with fructose; lactose was also given to a group of volunteers. Two groups of subjects received the standard galactose meal alone and with a simultaneous intravenous infusion of glucose or insulin. There was a marked individual variation in the serum galactose response to the standard galactose meal, the maximum galactosemia ranged from 0.23 to 4.56 mmole/L. Peroral glucose suppressed the serum galactose response to galactose producing significant reductions in the mean area under the serum galactose response curves. At a glucose intake of 0.15 g/kg by-32 +/- 14.3%, 0.50 g/kg BW -69 +/- 5.93% and at 0.75 g/kg BW -75 +/- 4.93%. Ingestion of glucose with galactose did not increase galactose loss in the urine. Lactose produced similar serum galactose, glucose and insulin responses to those seen after administration of equal quantities of galactose and glucose as monosaccharides. Fructose did not affect serum galactose levels when given with the standard galactose meal. Intravenous glucose produced a significant reduction of 56 +/- 14.1% in the mean area under the galactose response curve [p less than 0.01], whereas intravenous insulin did not affect the serum galactose response to peroral galactose.

Campylobacter enteritis: a large outbreak traced to commercial raw milk

From April 24 to May 11, 1981, an outbreak of approximately 200 cases of Campylobacter jejuni enteritis occurred in Arizona in persons who drank one brand of unpasteurized milk. Two cohort studies showed that households with members who drank raw milk reported diarrheal illness significantly more frequently than those in which no one drank raw milk (P=.003 and P=.001; relative risk 4.70 and 3.85, respectively). Of 19 serotyped C jejuni organisms isolated from persons who drank raw milk from the implicated dairy, 18 were of a single serotype.C jejuni was not detected in the milk or the milk filters cultured a week after the outbreak, but fecal excretion of Campylobacter of multiple serotypes was higher in the dairy herd that produced the implicated raw milk (48 percent) than in control herds (16 percent).

Is Peyronie's disease iatrogenic?

Three cases of Peyronie's disease are described, in which the condition is associated with hypertension and atherosclerosis. Another common factor is the use of beta-blocking agents in their treatment. A plea is made for an urgent review of the aetiology of Peyronie's disease bearing in mind the possibility of an iatrogenic cause.

The Angelman ("happy puppet") syndrome

We report studies of six patients with the Angelman "Happy Puppet" syndrome and compare the data with those from previous reports. The results confirm the classic findings of severe mental retardation, "puppet-like" gait, characteristic craniofacial abnormalities, and frequent episodes of laughter and suggest that this syndrome is more common than previously thought. Computerized axial tomographs of the brain demonstrating unilateral cerebellar atrophy in one patient constitute the first direct evidence of cerebellar abnormalities in this syndrome.

Metabolic effects produced in baboons associated with the ingestion of diets based on lactose hydrolysate

Diets containing 80% by weight carbohydrate provided by lactose hydrolysate (prepared by two different techniques), sucrose or glucose were given to baboons for 10-week periods. Fasting blood samples were taken regularly and the serum was assayed for galactose, glucose, insulin, triglyceride and cholesterol. The body weight of the animals was recorded. During both lactose hydrolysate dietary periods the mean fasting serum galactose concentration increased whereas the fasting serum glucose level fell initially. The fasting serum glucose concentration rose with both the glucose and the sucrose diets. The fasting serum triglyceride concentration of the female baboons increased significantly during both periods of ingestion of lactose-hydrolysate-based diets whereas the glucose and sucrose diets did not produce a significant effect. The sucrose diet produced a consistent increase in the mean triglyceride level of the male baboons. The mean serum cholesterol fell in the male and female baboons during all four diets.

A genetic locus responsible for salmonella susceptibility in BSVS mice is not responsible for the limited T-dependent immune responsiveness of BSVS mice

BSVS mice are known to be highly susceptible to salmonella infection. We have shown that the bulk of the difference in susceptibility between BSVS and salmonella-resistant A/J mice is the result of a genetic difference at a single locus not closely linked to H-2, Igh-C, or Hbb, and not X-linked. We have backcrossed the A/J allele at this locus into BSVS mice for 8 successive generations and have demonstrated that the salmonella resistance afforded by this allele is not the result of a restoration of the generalized poor T-dependent responsiveness of BSVS mice. The salmonella resistance locus we have examined with these 2 strains is probably the same as the Ity locus described by others.

A genetic locus responsible for salmonella susceptibility in BSVS mice is not responsible for the limited T-dependent immune responsiveness of BSVS mice

BSVS mice are known to be highly susceptible to salmonella infection. We have shown that the bulk of the difference in susceptibility between BSVS and salmonella-resistant A/J mice is the result of a genetic difference at a single locus not closely linked to H-2, Igh-C, or Hbb, and not X-linked. We have backcrossed the A/J allele at this locus into BSVS mice for 8 successive generations and have demonstrated that the salmonella resistance afforded by this allele is not the result of a restoration of the generalized poor T-dependent responsiveness of BSVS mice. The salmonella resistance locus we have examined with these 2 strains is probably the same as the Ity locus described by others.

The blood flow through the "resting" arm during hand-grip contractions

These experiments were designed to add information about the control of the circulation in the contralateral arm during isometric hand-grip contractions. The existing evidence came from two laboratories and was in conflict. The most recent data claimed that there is an inevitable increase in blood flow through the contralateral arm and that it is neurogenically controlled, while some degree of electromyographic activity was not associated with an increase in the blood flow. In the present experiments, the blood flow and the oxygen uptake over the arm were first "calibrated" against the electromyographic activity during isometric contractions at known low tensions. In steady state conditions, there were direct, linear relationships between all four measurements. The "calibrated" arm then became the contralateral (resting) arm, while strong isometric contractions were held by the other hand. Of 12 subjects examined, half showed no increase in blood flow or electromyographic activity. The other six subjects all showed some muscular activity (electromyogram) in the contralateral arm which was always associated with an increase in blood flow and oxygen uptake. Not all those findings fitted the "calibration" closely; the problems of this approach are discussed.

Rat neural antigen-2 (RAN-2): a cell surface antigen on astrocytes, ependymal cells, Müller cells and lepto-meninges defined by a monoclonal antibody

We have immunized mice with enriched populations of cultured rat astrocytes and fused their spleen cells with NS-1 myeloma cells to generate antibody-secreting hybridomas. We have isolated two stable hybridoma clones which secrete monoclonal IgG2 antibodies that react with the surface of the great majority of rat astrocytes in culture. We have studied one of these antibodies in indirect immunofluorescence assays and show that it binds to the surface of rat ependymal cells, retinal Müller cells and leptomeningeal cells as well as to astrocytes, but not to cultured neurones, oligodendrocytes, Schwann cells, microglia or various non-neural cells. The antigen defined by this monoclonal antibody is protease-sensitive and rat-specific and we have called it rat neural antigen-2 (Ran-2). We also show that isolated rat ependymal cells and cultured rat Müller cells do not express other neural cell-type-specific markers, such as tetanus toxin receptors, rat neural antigen-1 (Ran-1), galactocerebroside or glial fibrillary acidic protein (GFAP). Nor do these cells express cell surface Fc receptors for IgG, phagocytose latex beads or make detectable amounts of the Thy-1 or fibronectin glycoproteins.

Measurement of forearm blood flow by venous occlusion plethysmography: influence of hand blood flow during sustained and intermittent isometric exercise

The requirement for using an arterial occlusion cuff at the wrist when measuring forearm blood flows by plethysmography was tested on a total of 8 subjects at rest and during and after sustained and intermittent isometric exercise. The contribution of the venous effluent from the hand to the forearm flow during exercise was challenged by immersing the arm in water at 20, 34, and 40 degrees C. Occlusion of the circulation to the hand reduced the blood flow through the resting forearm at all water temperatures. There was an inverse relationship between the temperature of the water and the proportion in the reduction of forearm blood flow upon inflation of the wrist-cuff, ranging from 45 to 19% at 20 degrees to 40 degrees C, respectively. However, during sustained isometric exercise at 10% of the subjects maximum voluntary contraction (MVC) there was no reduction in the measured forearm flow when an arterial occlusion cuff was inflated aroung the wrist. Similarly, there was no alteration in the blood flow measured 2 s after each of a series of intermittent isometric contractions exerted at 20% or 60% MVC for 2 s whether or not circulation to the hand was occluded nor of the post-exercise hyperemia following 1 min of sustained contraction at 40% MVC. These results indicate that a wrist-cuff is not required for accurate measurement of forearm blood flows during or after isometric exercise.

The control of blood flow through human forearm muscles following brief isometric contractions

1. The blood flow through the forearm was measured 2 sec after single, brief isometric hand-grip contractions. The tension and duration of those contractions varied from 10 to 100% of the maximal voluntary contraction (m.v.c.) and from 2 to 12 sec, respectively. 2. The blood flow increased linearly with tension up to about 60% m.v.c. but further increases in tension, up to 100% m.v.c., did not elicit higher blood flows than were found at 60% m.v.c. The same relationship between tension and the resultant blood flow held for all durations of contractions, from 2 to 12 sec. The blood flow immediately after (2 sec) contractions at a given tension increased linearly with the duration of the contraction, from 2 to 12 sec. Maximal exercise blood flow was approached only in response to the longest contractions (12 sec) at tensions of 60% m.v.c. or higher. 3. Brief alterations (2--5 sec) of transmural pressure across blood vessels did not result in a significant change of blood flow, either in the resting forearm or when the vessels were dilated by brief, isometric contractions. When the tension was applied or released either rapidly or gradually ('ramp' contractions) there was no correlation between the rate of change of stretch on arterial vessels and the resultant blood flow. However, there was a direct relationship between a force--time integral (duration of contraction x peak tension) and blood flow. All these results make it clear that changes in blood flow in the forearm elicited by brief isometric contractions are not the result of a myogenic reflex but are metabolically induced. 4. Successive contractions exerted at 60% m.v.c. for 4 sec induced a blood flow of 21.2 +/- 1.6 ml.min-1.100 ml.-1 when a rest interval of 8 sec was allowed between the contractions. Blood flows remained constant at this submaximal level, even when muscular fatigue was induced, and when there was an accompanying large increase in blood pressure. 5. Isometric muscular activity by the contralateral arm which resulted in fatigue, associated with a large increase in mean blood pressure, did not alter the level of vasodilation that was induced by brief, isometric contractions in the 'test' arm. 6. It is suggested that the vasodilatation in response to intermittent isometric contractions is the result of metabolic vasodilatation of distal segments and continued sympathetic vasoconstriction of the proximal segments of the forearm vascular bed.