Segmental definition--Part IV. Updating the differential for somatic and visceral inputs.

The first three parts of this series presented a standardized method of motion testing for motor behaviors specific to segmental dysfunction. When applied to clinical research studies, analysis of these palpatory data differentiated viscero-somatic from somato-somatic reflex manifestations in the thoracic region of subjects with renal dysfunction and/or hypertension. This update for the differential adds new observations regarding palpable findings, specifically at the spinal levels where linkage of costal and vertebral motion asymmetries identified the presence of increased visceral inputs. At each level, the examiner can make a simple comparison for accord in response to two sidebending motion tests in the seated position, one introduced through the shoulders and trunk and one through the head and neck. Lack of accord is a distinctive characteristic of the linked spinal/costal site of visceral input. Also, with regard to linkage sites, behavioral responses to motion tests introduced through the lower extremities suggest new applications for manipulative intervention. The new descriptive clinical data about segmental motion behaviors described in this report provide a basis for new questions in neuromusculoskeletal research.

Clinical biomechanic correlates of cervical dysfunction: Part 4. Altered regional motor behavior.

The present study examined organizational patterns of individual muscular contributions to head and neck motion. Previous studies of asymptomatic subjects with cervical motor asymmetry identified significant kinematic and myoelectric alterations. The current study evaluated 34 asymptomatic subjects categorized as to symmetry group based on initial palpatory test comparing regional motion responses of the head and neck to sidebending right and left. Electromyographic techniques were used to study muscular activity, indicating contraction frequency for each muscle monitored during active and passive test motions. Subjects with diagnosed regional motion asymmetry exhibited a significantly altered organization of electrically active and electrically silent muscles. Their pattern of muscle contraction was compromised just as frequently in the passive as in the active phases of motion. A positive sign of motion asymmetry on physical examination of the cervical region alerts the physician early to the presence of significant dysfunction in motor organization for efficient head/neck movement. The adaptive motor patterning in dysfunction can occur before the appearance of subjective pain.

Cloning and tissue distribution of the Aplysia Na+ channel alpha-subunit cDNA.

Voltage-gated Na+ channels generate the depolarizing inward current that is critical for the initiation and conduction of action potentials. To study the roles of Na+ channels in neuronal signaling, we have begun the molecular analysis of Na+ channels in Aplysia californica. We have isolated cDNAs that encode a neuronal Na+ channel alpha-subunit, which we have named SCAP1. DNA sequence analysis of the SCAP1 cDNA revealed an open reading frame that predicts a protein of 1,993 amino acids, which is highly similar to other members of the Na+ channel alpha-subunit gene family. RNase protection assays carried out on various Aplysia tissues indicated that SCAP1 is expressed predominantly in the nervous system. All of the nonneuronal tissues tested were negative with the exceptions that low levels of expression were observed in ovotestis and parapodium, probably due to the presence of small numbers of neurons within these tissue preparations. Southern blot hybridization at reduced stringency indicated that the genome of Aplysia contains more than one Na+ channel alpha-subunit gene.

Standardization of the hospital record for osteopathic structural examination: Part 2. Effects of an educational intervention on documentation of palpatory and structural findings and diagnosis.

The purpose of this two-part study was to develop and test an instructional videotape for use in the osteopathic hospital setting; to standardize a procedure for documentation of palpatory and structural findings and diagnoses; and to examine the program's influence on the correlation of palpable and structural findings with a diagnostic impression of somatic dysfunction. To that end, the authors analyzed results of a survey of the medical records of 20 osteopathic training hospitals. Patients' charts were randomly pulled before and after house staff who performed admitting hospital examinations viewed an educational videotape. The videotape emphasized that the structural and palpatory screening examination should simply answer the question, "Is there a problem in the musculoskeletal system?" Chi-square analysis was used to evaluate the frequency of documentation of altered structural findings (structure, motion, tissue changes) and the diagnostic impression of somatic dysfunction and their correlation. Based on more than 300 reviewed charts, the authors found that the frequency of documentation of structural and palpatory examination was not significantly altered after house staff viewed the videotape. A sequence of hospital-based instruction in osteopathic principles and practices has been initiated at more than 50 osteopathic medical institutions, and the problems related to continuing medical education and clinical research in osteopathic medicine are discussed.

Clustered voltage-gated Na+ channels in Aplysia axons.

Clustering of voltage-gated Na+ channels is critical for the fast saltatory conduction of action potentials in vertebrate myelinated axons. However, the mechanisms responsible for the generation and maintenance of Na+ channel clustering are not well understood. In this study we have raised an antibody against the cloned SCAP-1 voltage-gated Na+ channel of the marine invertebrate Aplysia californica and used it to examine Na+ channel localization in Aplysia ganglia and in cultured Aplysia sensory neurons. Our results show that there is a large cytoplasmic pool of Na+ channels in the soma of Aplysia neurons. Furthermore, we show that Na+ channels in Aplysia axons are not homogeneously distributed but, rather, are present in distinct clusters. Theoretical considerations indicate that Na+ channel clustering may enhance action potential conduction. We propose that clustered Na+ channels may be a fundamental property of many axons, and perhaps of many membranes that conduct Na(+)-dependent action potentials.

Risk of chromosomal abnormalities, with emphasis on live-born offspring of young mothers.

In a large public urban hospital obstetrics service with > 123,000 deliveries in a 10-year period (1980-89), the frequencies (0.12%) of any type of chromosomal abnormality and of trisomy syndromes were analyzed for maternal age-related risk, by logistic regression. Focusing on very young gravidas, we found that in the study period there were 9,332 births (7.5% of all deliveries) to mothers < or = 16 years old. Estimated risks of chromosomal abnormalities among offspring associated with very young maternal age (9-16 years) were similar to those age-associated risks of mothers 20-29 years old. Risks of chromosomal abnormalities increase with advancing maternal age and are independent of ethnicity.

Changes in presence of a segmental dysfunction pattern associated with hypertension: Part 2. A long-term longitudinal study.

The short-term portion of this study (part 1) showed an association between somatic dysfunction and the regulation of blood pressure. To study long-term relationships, follow-up examinations were made of 61 subjects studied 3 to 10 years earlier. They were heterogeneous Family Practice Clinic patients with a mean age of 45 years. By methods used in part 1 and in our previous studies of systemic interactions, palpatory examination was done to support presence or absence of a C6T2T6 pattern of segmental motion dysfunctions, and blood pressure status was established by the medical history. The C6T2T6 pattern persisted in 16 of 16 subjects with grade 2 or greater hypertension and 4 of 9 normotensive subjects who had shown the pattern initially. At follow-up, the pattern first appeared in 7 subjects who had hypertension previously diagnosed and who remained hypertensive; the pattern disappeared in 5 normotensive subjects who remained normotensive. The C6T2T6 pattern's long-term persistence in hypertensive subjects and changes in its presence corresponding to the subjects' hypertensive status indicate an important relationship between this pattern of segmental motion dysfunctions and disturbances in regulation of blood pressure.

Changes in presence of a segmental dysfunction pattern associated with hypertension: Part 1. A short-term longitudinal study.

A statistically significant pattern of segmental components of somatic dysfunction associated with a history of high blood pressure was investigated for change after an interval of 4 to 8 months. The volunteer subjects, from an inner-city ambulatory clinic, included normotensive, borderline hypertensive, and hypertensive persons. A standardized palpatory examination determined whether there were specific motion asymmetries centered at spinal segments C6, T2, and T6 and confirmed by mirror-image motion asymmetries in adjacent segments. Blood pressure measurements and diagnosis of hypertension followed American Heart Association standards. The repeated presence of the pattern in subjects with a history of hypertension was statistically significant. Presence of the pattern in normotensive subjects, however, appeared to be random. The subjects' histories during the study period revealed no influence of antihypertensive medications, major accidents, or illness on the patterns' continuing presence in subjects requiring medical control of their hypertension.

Standardization of the hospital record for osteopathic structural examination: recording of musculoskeletal findings and somatic dysfunction diagnosis.

The diagnosis of somatic dysfunction is supported by the recording of positive musculoskeletal findings (altered structure, motion, tissue). We conducted a national survey to assess the status of the documentation of this relationship in the hospital setting. The 26 participating osteopathic training hospitals submitted 719 admitting physical examination forms, of which 417 (58%) met study criteria (adult patients on medicine or surgical service with a musculoskeletal examination documented on the chart). On 234 charts (56%), at least one positive finding was recorded but no diagnosis of somatic dysfunction was stated. Of 14 charts with a diagnosis of somatic dysfunction, 10 had a positive musculoskeletal finding recorded. The relationship between positive musculoskeletal findings and somatic dysfunction is not being documented on osteopathic training hospital admitting physical examination forms. Proper documentation of a somatic dysfunction diagnosis and related positive musculoskeletal findings will enable multisite research on the relationship between somatic dysfunction and other health problems documented on the hospital medical record. A multiple data collection system that is workable, reliable, and reproducible was developed as a result of this study.

Acute dietary PCPA treatment decreases the KD of brain [3H]5-HT binding in rainbow trout, Oncorhynchus mykiss, fed a high carbohydrate diet.

Two experiments were conducted to determine the effect of dietary PCPA on brain [3H]5-HT binding in rainbow trout. [3H]5-HT binding was quantitatively similar to that observed in mammalian species. Dietary treatment with PCPA had no effect on the Bmax of [3H]5-HT binding in either experiment while the KD was decreased in Experiment 1. These results demonstrate that [3H]5-HT binding affinity is increased following short term inhibition of 5-HT synthesis by PCPA in rainbow trout.

Reliability of birth certificate reporting of congenital anomalies.

Birth certificates comprise an important source of data on the prevalence of genetic conditions and for monitoring possible teratogens in the population. Investigators have found wide variability (12 to 100%) in the accuracy of reporting. In a large public hospital, of those congenital anomalies detected at birth, only 5.4% were recorded on the birth certificate. This is one of the lowest rates ever reported. An underreporting correction factor may be applied if congenital anomalies are distributed randomly with respect to reporting status, and the rate of reporting is sufficient to comprise a valid sample for estimating a correction factor (that is, 20% or more reported). In this study, factors such as numbers or types of anomalies, race, infant birthweight, or estimated gestational age did not significantly influence the rate of birth certificate reporting. Thus, our data satisfied the first but not the second criterion for derivation of a correction factor. In conducting epidemiologic studies, birth certificate data should be used with: (1) great caution; (2) a system of validation with the medical record to estimate the degree of underreporting and to derive a correction factor; and (3) a priori knowledge that underreporting of congenital anomalies on this document is highly prevalent.

Effect of feeding and fasting on plasma tryptophan and tryptophan to large neutral amino acid ratio, and on brain serotonin turnover in rainbow trout,Oncorhynchus mykiss.

Two time-course experiments were conducted to determine the effect of feeding and fasting on the plasma ratio of tryptophan (trp) to the large neutral amino acids (LNAA), (trp/LNAA ratio) and brain serotonin (5-HT) turnover in rainbow trout,Oncorhynchus mykiss. Trout were fasted overnight or for 3 days and were then either fed or continued to be fasted for up to a further 3 days. Changes in plasma trp, plasma trp/LNAA ratio, brain trp, brain 5-HT, brain 5-hydroxyindoleacetic acid (5-HIAA) and brain 5-HIAA/5-HT ratio were determined over time. Feeding decreased the plasma trp/LNAA ratio, brain trp and the brain 5-HIAA/5-HT ratio. In addition, in fish sampled over 3 days, there appeared to be a rhythm in plasma trp and the brain 5-HIAA/5-HT ratio which was independent of feeding. These results indicate that in rainbow trout, feeding is a sufficient physiological event to decrease brain 5-HT turnover. Furthermore, feeding-independent changes in the brain 5-HIAA/5-HT ratio, which were evident in fasted fish sampled over 3 days, also suggest an additional, non-feeding-related modulator(s) of brain 5-HT turnover in rainbow trout.

HIV prevalence in pregnant intravenous drug users in Dallas, Texas.

Information available regarding the prevalence of human immunodeficiency virus (HIV) in pregnant women indicates that the primary risk factor for infection is intravenous drug use. At Parkland Memorial Hospital in Dallas, Texas, approximately 4.7% of pregnant women reported using intravenous drugs. The estimated prevalence of HIV infection among pregnant intravenous drug users at this hospital was 3.3%. This is similar to the HIV infection rates reported for nonpregnant parenteral drug-using populations in other areas of the southwestern United States, suggesting that there may be a lower rate of endemic infection in this region of the country.

Clinical biomechanic correlates for cervical function: Part III. Intermittent secondary movements.

Parts I and II of this study compared kinematic and myoelectric data for two groups of asymptomatic subjects classified as having symmetric or asymmetric motor response to a palpatory test for cervical sidebending. Kinematic data revealed that asymmetric subjects had limited mobility for primary and secondary motions. Myoelectric activity was slow to be initiated in the asymmetric subjects, and reduced in time and strength of contraction. Part III addresses additional specific kinematic data concerning three-dimensional orientations of the head; however, these data were accumulated throughout the paths of movement, not just at their end points as in our previous work. Although asymmetric subjects had demonstrated significantly reduced range of motion, paths of the more minor secondary axes did not differ significantly between groups. As with previous data (Part I and II), active and passive movements were undifferentiated; this degree of likeness in even minor aspects of the motor performance continues to indicate the remarkable similarities that can exist between primary movements directed and guided by trained physicians and those actively controlled by patients themselves. Part III completes a study of cervical motor behavior in which a passive gross motion test distinguished an asymmetric group with subclinical motor behavior that has measurable kinematic and myoelectric correlates.

Nomograms for rapid estimation of intravascular intrauterine exchange transfusion.

Fetal exchange transfusion is complicated by the fact that vascular access must be maintained while the number of exchanges needed to achieve a desired post-transfusion hematocrit is calculated. A rapid method for estimating the number of exchange transfusions would greatly simplify fetal exchange transfusion for blood group isoimmunization. In this report, we present a graphic method for determining the number of exchange transfusions necessary to achieve a post-transfusion hematocrit of 45%, using a nomogram for 5- and 10-mL exchange transfusion volumes.

Patterns of multiple substance abuse during pregnancy: implications for mother and fetus.

This paper describes patterns of drug use such as choice of drug, other substances abused, and route of administration in 174 women who reported methamphetamine, cocaine, heroin, or "Ts and blues" abuse during pregnancy. Seventy-five percent (130/174) reported using more than one drug. Other than tobacco, alcohol and cocaine were the drugs most frequently used in combination with other drugs (7% to 53% and 12% to 54% of the time, respectively). The extent of polydrug use observed in this study emphasizes (1) the difficulty in ascribing adverse maternal or fetal health effects to single substances, and (2) the potential for interaction effects due to multiple substance abuse.

Effect of dietary tryptophan on plasma and brain tryptophan, brain serotonin, and brain 5-hydroxyindoleacetic acid in rainbow trout.

In order to determine the effect of dietary tryptophan level on plasma and brain tryptophan, brain serotonin, and brain 5-hydroxyindoleacetic acid levels, juvenile rainbow trout (Salmo gairdneri) were raised for 16 weeks on semipurified diets containing 0.06%, 0.16%, 0.21%, 0.26%, 0.39%, or 0.59% tryptophan. After 14 weeks, feed intake was depressed in fish fed the diets containing 0.06% or 0.16% tryptophan. No further differences in feed intake were noted between the remaining treatments. In addition, body weight was lower in fish fed diets containing 0.06%, 0.16%, or 0.21% tryptophan compared with fish fed higher levels. After 16 weeks of feeding the test diets, plasma tryptophan levels were found to be directly related to dietary tryptophan levels. Similarly, increased dietary levels of tryptophan resulted in increased brain levels of tryptophan, serotonin, and 5-hydroxyindoleacetic acid. These results demonstrate that in rainbow trout, as in mammals, altered dietary levels of tryptophan result in alterations in plasma and brain tryptophan, brain serotonin, and brain 5-hydroxyindoleacetic acid.

Blood lead levels and growth status of children.

Several studies have shown that elevated blood lead (Pb) levels in children are associated with decreased growth. Among 139 children aged 1 to 10 years (66 male, 73 female) who attended a Pb clinic in Dallas, Texas, growth was decreased by 1.6 cm in height, 1.4 kg in weight, and 0.6 cm in head circumference for each 10 µg/dl increase in blood Pb. Consistent with previously reported effects of Pb, several clinical symptoms (hearing deficit, dental problems, hyperactivity) were increased in frequency among children with high blood Pb levels (X̄Pb = 34.6 µg/dl ± 5.6) compared to the children in the low Pb level group (X̄Pb = 11.9 µg/dl ± 3.3). Interestingly, pica was significantly increased in frequency among children in the high Pb group, indicating oral consumption of non-food matter was a major source of Pb intoxication. These results suggest that increased Pb level is an important risk factor for growth deficits in children.