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J McCormick

Publications and source records attributed to J McCormick.

At least 37 records · Page 2Linked to original sources
PubMed1999

Differential processing of neuropeptides influences Drosophila heart rate.

Peptides that play critical physiological roles are often encoded in precursors that contain several structurally-related gene products. Differential processing of a precursor by cell-specific processing enzymes can yield multiple messengers with diverse distributions and activities. We have reported the isolation of SDNFMRFamide, DPKQDFMRFamide, and TPAEDFMRFamide from adult Drosophila melanogaster. The peptides are encoded in the FMRFamide gene and have a common C-terminal FMRFamide but different N-terminal extensions. In order to investigate the processing of the FMRFamide polypeptide protein precursor, we generated antisera to distinguish among the structurally-related neuropeptides. Utilizing a triple-label immunofluorescent protocol, we mapped the distribution of the peptides. Each peptide has a unique, non-overlapping cellular expression pattern in neural tissue suggesting that the precursor is differentially processed. In order to identify a biological activity of the peptides, we established an in vivo heart rate assay. SDNFMRFamide decreases heart rate but DPKQDFMRFamide and TPAEDFMRFamide do not, indicating that the N-terminal residues are critical for this activity. SDNFMRFamide immunoreactivity is present in the aorta, implying that SDNFMRFamide acts locally to affect heart rate; DPKQDFMRFamide and TPAEDFMRFamide antisera do not stain cardiac tissue. Our data support the conclusion that Drosophila contains cell-specific proteolytic enzymes to differentially process a polypeptide protein precursor resulting in unique expression patterns of structurally-related, yet functionally distinct neuropeptides.

Analysis of Variance↗
PubMed1999

Basketball injuries in a rural area.

This study was conducted to determine the frequency and nature of basketball injuries occurring in a rural setting. More than 6000 patients with sports-related injuries presented to a rural emergency department between June 1, 1988 and June 1, 1994. Of these patients, 1189 (19% of the total) were injured playing basketball. A chart abstraction form was utilized to retrospectively review injuries noting demographics, types and sites of injuries, as well as referral and treatment plans. Approximately two-thirds (66.4%) of those injured were males, with most injuries (53%) occurring during school-related activities. Almost four-fifths (78%) of injuries occurred between the ages of 10 and 19. The ankle (33.1%) was the body site most commonly injured, followed in frequency by finger injuries (19.3%), sprains and strains, which accounted for the majority (55%) of injuries. The most common mechanism of injury was recorded in which no contact with other players occurred (37.4%). The vast majority (99%) of injuries were managed as outpatients. The majority of cases (72%) were expected to recover within 2 weeks. Similarities were noted regarding sites of injury and age of distribution of patients when compared to the previous studies.

Adolescent↗
PubMed1998

High-altitude cerebral edema evaluated with magnetic resonance imaging: clinical correlation and pathophysiology.

CONTEXT: Because of its onset in generally remote environments, high-altitude cerebral edema (HACE) has received little scientific attention. Understanding the pathophysiology might have implications for prevention and treatment of both this disorder and the much more common acute mountain sickness. OBJECTIVES: To identify a clinical imaging correlate for HACE and determine whether the edema is primarily vasogenic or cytotoxic. DESIGN: Case-comparison study. SETTING: Community hospitals accessed by helicopter from mountains in Colorado and Alaska. PATIENTS: A consecutive sample of 9 men with HACE, between 18 and 35 years old, 8 of whom also had pulmonary edema, were studied after evacuation from high-altitude locations; 5 were mountain climbers and 4 were skiers. The control group, matched for age, sex, and altitude exposure, consisted of 3 subjects with high-altitude pulmonary edema only and 3 who had been entirely well at altitude. Four patients with HACE were available for follow-up imaging after complete recovery. MAIN OUTCOME MEASURES: Magnetic resonance imaging (MRI) of the brain during acute, convalescent, and recovered phases of HACE, and once in controls, immediately after altitude exposure. RESULTS: Seven of the 9 patients with HACE showed intense T2 signal in white matter areas, especially the splenium of the corpus callosum, and no gray matter abnormalities. Control subjects demonstrated no such abnormalities. All patients completely recovered; in the 4 available for follow-up MRI, the changes had resolved entirely. CONCLUSIONS: We conclude that HACE is characterized on MRI by reversible white matter edema, with a predilection for the splenium of the corpus callosum. This finding provides a clinical imaging correlate useful for diagnosis. It also suggests that the predominant mechanism is vasogenic (movement of fluid and protein out of the vascular compartment) and, thus, that the blood-brain barrier may be important in HACE.

Adult↗
PubMed1998

Outbreak of Crimean-Congo haemorrhagic fever in Quetta, Pakistan: contact tracing and risk assessment.

In December 1994 in a private hospital in Quetta, Pakistan, 3 health-workers contracted Crimean-Congo haemorrhagic fever (CCHF) after surgery on a bleeding patient who later died. We conducted a retrospective study to determine transmission risks among contacts. Fifty contacts gave blood for antibody tests and answered questions about exposure. Two of four people exposed percutaneously and one of five with cutaneous exposure contracted CCHE The person with cutaneous exposure was a surgeon who tore his glove during surgery and noted blood on his hand but no cut. There were no anti-CCHF antibodies or CCHF cases among persons whose skin came into contact with body fluids other than blood (0/4), who had skin-to-skin contact (0/16) with patients or were physically close to them (0/21). Three index case relatives reported that although 10 family members had cutaneous exposure, none developed CCHF. The family refused blood tests. CCHF transmission in resource-constrained settings can be limited by focusing on avoiding health worker contact with blood.

Disease Outbreaks↗
PubMed1997

Dromyosuppressin and drosulfakinin, two structurally related Drosophila neuropeptides, are uniquely expressed in the adult central nervous system.

Drosophila myosuppressin (TDVDHVFLRFamide; DMS) and sulfakinin (FDDYGHMRFamide; DSK) have similar C-terminal structures. To determine the neuronal expression patterns of these structurally related peptides, we have generated DMS- and DSK-specific antisera to multiple antigenic peptides and performed double-label immunochemistry with antisera raised on different animals of the same species host animal. Our data indicate that DMS and DSK staining patterns in the adult central nervous system are unique and nonoverlapping.

Amino Acid Sequence↗
PubMed1997

Multiple antigenic peptides designed to structurally related Drosophila peptides.

We have isolated TDVDHVFLRFamide (DMS), FDDYGHMRFamide (DSK), and DPKQDFMRFamide from Drosophila melanogaster. These peptides, structurally related by a common C-terminus -XRFamide, where X = L or M, are encoded by three different genes. To determine cellular expression, we have generated antisera to multiple antigenic peptides and performed double-label immunofluorescence using antisera raised in the same species host animal. Our results indicate that DMS and DSK immunoreactive materials have unique, non-overlapping expression patterns, while DMS and DPKQDFMRFamide immunoreactive materials colocalize in two superior protocerebrum neurons, and DSK and DPKQDFMRFamide immunoreactive materials colocalize in one superior protocerebrum neuron, one subesophageal ganglion neuron, and three thoracic ganglia neurons.

Animals↗
PubMed1997

The multiple meanings of long-term gastrostomy in children with severe disability.

Although the physiological implications of long-term gastrostomy for children with severe disability are well documented in the nursing literature, little is known about the psychosocial effect of this technological intervention. This study documents and interprets the perspective of expert nurses and parents to reveal conflictual social processes associated with gastrostomy decision-making and the intense moral dilemma that these processes create. The findings suggest that gastrostomy denotes multiple meanings for parents and health care providers, and that an appreciation for these meanings can have a significant positive impact on nursing care for these children and their families.

Attitude of Health Personnel↗
PubMed1997

Examination-induced distress in a public examination at the completion of secondary schooling.

BACKGROUND: The context for this study was the Higher School Certificate examination in New South Wales, Australia. AIMS: The main research aim was to investigate the association between the Higher School Certificate, the reported distress and anxiety levels of the adolescent students who prepare for and sit for the examination, and various other internal and environmental variables. SAMPLE: The random sample consisted of 445 students in their last two years of secondary schooling, with approximately equal numbers of males and females from a diverse range of ethnic backgrounds. METHODS: Analysis was carried out using principal components analysis and multiple regression. RESULTS: The most significant contribution to distress associated with the examination was made by the personality trait, anxiety proneness. Lower socio-economic status, self-confidence, academic and verbal self-concepts and perceived ability to cope were also found, to a lesser extent, to be associated with increased distress. The interactions sex with ethnic background and year with ethnic background were of particular interest. Students who were male and had an English speaking background, and students in year 11 who had an English speaking background were least likely to experience distress than others in the context of the examination. CONCLUSIONS: Whilst results must be treated with caution, particular groups of students potentially vulnerable to distress were identified and directions for future research indicated.

Adolescent↗
PubMed1997

Peritoneovenous shunts in patients with intractable ascites: palliation at what price?

Intractable ascites carries great morbidity by affecting appetite, mobility, and quality of life. Peritoneovenous shunts (PVSs) are utilized to abate intractable ascites, although long-term efficacy is unestablished. Thirty male and 18 female cirrhotics, 55 +/- 12 (standard deviation) years of age, failed multiple large-volume paracenteses and diuretic therapy before undergoing PVS. Data were collected until death or the present time. Nine patients (19%) are alive and palliated, four with working shunts [average follow-up (ave. f/u), 30 months] and five without shunts (ave. f/u, 19 months). Thirty-two (67%) patients died: 18 palliated with functional shunts (survival time, 4.4 +/- 5.7 months), 8 unpalliated with dysfunctional shunts (ave. f/u, 3.9 +/- 4.5 months), 4 unpalliated with shunts removed (ave. f/u 5.5 +/- 4.7 months), and 2 with unknown shunt function at death. Function was lost to occlusion in 26 patients, infection in 9, and ligation for disseminated intravascular coagulation in 3. Thirteen patients underwent 18 shunt replacements. At death/present time, 22 (46%) patients were palliated with functioning shunts. Seven patients were lost to follow-up. PVSs provide palliation for intractable ascites short term, but commonly occlude within 1 year. Despite palliation, complications with PVSs are high, and survival is limited.

Ascites↗
PubMed1996

Synthesis and activity of a novel series of 3-biarylquinuclidine squalene synthase inhibitors.

Quinuclidines with a 3-biaryl substituent are a new class of potent, orally active squalene synthase (SQS) inhibitors. Variants around these rigid structures indicate key structural requirements for cationic SQS inhibitors. Thus the lower in vitro potency found for quinuclidines bearing 3-substituents, which did not overlay the biphenyl group of 3-(biphenyl-4-yl)-3-hydroxyquinuclidine (2) (IC50 = 16 nM, rat microsomal SQS), implied a directional requirement for the 3-substituent. Similarly, the lower potency of the 3-terphenyl analogue 6 (IC50 = 370 nM) indicated size constraints for this substituent. In compounds with a linking group between the quinuclidine and biphenyl ring, linking groups of lower lipophilicity were less well tolerated (e.g., 17, CH2CH2, IC50 = 5 nM vs 19, NHCO, IC50 = 1.2 microM). Replacement of the distal phenyl ring of 2 with a more polar pyridine heterocycle caused a reduction in in vitro potency. In general, good in vivo activity in the rat was restricted to 3-hydroxy analogues, with the 3-[4-(pyrid-4-yl)phenyl] derivative 39 (IC50 = 161 nM) showing the best inhibition (following oral dosing) of cholesterol biosynthesis from mevalonate (ED50 = 2.7 mg/kg).

Animals↗
PubMed1996

Gait training efficacy using a home-based practice model in chronic hemiplegia.

OBJECTIVE: The efficacy of a home practice model for gait training was evaluated in 18 hemiplegic subjects 2.3 years (range, 1 to 5) after stroke. DESIGN: Uncontrolled case series. SETTING: Referral center. SUBJECTS: Patients at least 1 year poststroke referred to an outpatient rehabilitation program. INTERVENTION: Patients were taught home programs in two or more 2- to 5-day blocks averaging 35 physical therapy (PT) contact hours (range, 9.5 to 62.5); training extended over a mean of 22 months (range, 10 to 65). Training emphasized weight bearing, balance, segmental control, stretching, and bracing. MAIN OUTCOME MEASURES: Gait changes were measured using the newly developed Wisconsin Gait Scale (WGS). The patient-rated Falls Efficacy Scale (FES) was administered before and after training to 8 subjects, and the Health Status Questionnaire (HSQ) was retrospectively administered to all subjects to appraise subjective pretraining to posttraining changes and current psychological status. RESULTS: The average WGS score significantly improved (p < .05). Patients perceived that gait training increased the quality of their functional activities (p < .05). In a subset of patients, the FES showed that fear of falling was decreased (p < .05). Perception of well-being was comparable to a normative nonstroke reference population except for physical functioning. Compared to the only other published series (using traditional outpatient programming), the current model was of comparable cost. CONCLUSION: Despite the literature indicating a plateau in mobility function by 6 months after stroke, postacute training of gait in hemiplegic subjects using a home-based training model results in improved gait and the perception of improved function. Additionally, we provide validation for the newly developed Wisconsin Gait Scale, an instrument of gait measurement that may assist in comparing outcomes.

Activities of Daily Living↗
PubMed1996

Football injuries in a rural area.

This study was conducted to analyze the frequency and characteristics of football injuries in a rural hospital setting and compare it to the national data. More than 6,000 patients with a sport-related injury presenting to the emergency medicine department at the Marshfield Clinic between June 1, 1988 and June 1, 1994 were collected prospectively. Eight hundred forty-three (14% of total) patients sustained football-related injuries. A chart abstraction form was then used to retrospectively review football injuries documenting types, sites, and mechanism of injury, along with demographic aspects. The peak age sustaining football injuries was 17 years old (17.5%). Most of the football injuries occurred during school activities (73.7%). The most common site injured was the finger (16.5%), followed by the knee (15.7%). Sprains/strains were the most common diagnosis representing 40.2% of injuries overall. The most common mechanism resulting in a football-related injury was as a result of being blocked or tackled (52.7%). Surgery was required on 4.9% of individuals injured while playing football. Most patients (69.7%) were expected to recover from their injury within 14 days. There were more injured football players from our area in the age group 15 to 24 years as compared to the national data available. Diagnosis, site injured, and mechanism of injury from our study were comparable to other national publications. Prospective studies are needed to address the problem of football-related injuries. Such studies would require a multidiscipline team of experts.

Adolescent↗
PubMed1995

Management and prognosis of adenocarcinoma of the appendix.

PURPOSE: Adenocarcinoma of the appendix is a rare neoplasm, and controversies persist regarding management. The purpose of this study was to identify prognostic factors and define management strategies for patients with adenocarcinoma of the appendix. METHODS: A retrospective case series was conducted at three medical school teaching hospitals over a 20-year period from 1972 to 1992. Overall survival was determined by the actuarial life table method. Comparisons of prognostic factors were made using exact nonparametric log-rank tests. RESULTS: Thirteen patients were diagnosed during the study period. Median age was 62 years. There were five males and eight females. The disease was not suspected in any patient preoperatively. Seventy-seven percent of patients had metastatic disease at presentation. Second primary malignancies were found in 15 percent of patients. Thirty-eight percent of female patients had synchronous ovarian lesions. Median survival was 22 months, with an estimated five-year survival of 43 percent (95 percent confidence interval, 22-84 percent). Patients with colonic histology had significantly worse survival than patients with mucinous histology (P = 0.0093). Patients with carcinomatosis had a significantly worse survival than noncarcinomatosis patients (P = 0.0078). Patients who underwent right hemicolectomy had a better prognosis for survival than appendectomy patients, but the difference was not statistically significant. CONCLUSIONS: Carcinoma of the appendix is very difficult to diagnose preoperatively, and most patients are not identified until disease is advanced. Good prognostic factors include mucinous histology and the absence of carcinomatosis. Right hemicolectomy appears to be a reasonable option, although its superiority to appendectomy alone has not been definitively proven. High frequency of ovarian metastases in women suggests a role for bilateral oophorectomy. In addition, a complete work-up of the patient for a synchronous malignancy, especially in the gastrointestinal tract, should be considered.

Adenocarcinoma↗