Factors affecting adherence to a high-risk surveillance protocol among patients with Li-Fraumeni syndrome

BACKGROUND

High-risk surveillance for patients with Li-Fraumeni syndrome (LFS) has shown a stage shift and improved overall survival, but is demanding. Our objective was to evaluate surveillance adherence in a population of patients with LFS presenting for high-risk care.

METHODS

A retrospective analysis of surveillance adherence of adult patients with LFS at a single institution was performed. Adherence was defined by the duration from initial University of Virginia (UVA) LFS clinic visit to the time of first missed surveillance test. Two-sample t-tests and ANOVA tests were used to identify factors associated with duration of adherence.

RESULTS

A total of 42 patients were evaluated in the UVA LFS clinic between 2017 and 2021. Of these, 21 patients met inclusion criteria. At the time of review, 6 patients (29%) were up to date with high-risk surveillance recommendations. The mean duration of adherence was 17 months. Female sex was found to be associated with longer duration of adherence (mean 21 mo vs. 3.5 mo for males, p = 0.02). A personal history or active diagnosis of cancer was also associated with increased adherence (p = 0.02). However, neither age (p = 0.89), geography (p = 0.84), or known family history of LFS (p = 0.08) were associated with duration of adherence.

CONCLUSION

Female sex as well as a personal history of cancer were associated with longer duration of adherence to recommended high-risk surveillance among patients with LFS. Identification of barriers to surveillance will be essential moving forward to increase adherence and promote early detection of cancer, thereby reducing the morbidity and mortality of LFS.

Bloom syndrome in a Mexican American family with rhabdomyosarcoma: evidence of a Mexican founder mutation

Bloom syndrome is a rare autosomal recessive disorder with less than 300 cases reported in the literature. Bloom syndrome is characterized by chromosome instability, physical stigmata, growth deficiency, immunodeficiency, and a predisposition to cancer, most commonly leukemias, although solid tumors are reported as well. Bloom syndrome occurs in multiple ethnic groups with a higher incidence in persons of Ashkenazi Jewish origin. Few patients of Hispanic ethnicity have been reported. We report here a Mexican American family with a BLM pathogenic variant, c.2506_2507delAG, previously reported in a single patient from Mexico. In this family of four siblings, three have phenotypic features of Bloom syndrome, and BLM gene mutation was homozygous in these affected individuals. Our proband developed a rhabdomyosarcoma. Analysis of surrounding markers in the germline DNA revealed a common haplotype, suggesting a previously unrecognized founder mutation in the Hispanic population of Mexican origin.

Evaluation of breast screening strategies in a high risk breast and ovarian cancer clinic

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BRCA mutation carriers are more likely to be diagnosed with breast cancer compared to high-risk non-BRCA carriers.

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MRI was able to effectively identify DCIS in the BRCA population.

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In BRCA mutation carriers younger than 40, there were no MRI occult cancers found.

Recent data suggest that BRCA mutation carriers younger than 40 may not benefit from mammography in addition to MRI. Our objective was to evaluate screening modalities utilized in a high-risk population. Clinicopathologic data were abstracted for patients followed in a high risk clinic from 2007 to 2017. Descriptive statistics were calculated and associations between categorical variables were evaluated using chi-square tests. 631 women comprised the study population; 496 patients had no known mutation (79%), 128 (20%) had a BRCA mutation, and 7 patients had other deleterious mutations. BRCA mutation carriers were more likely to have cancers diagnosed after mammogram callbacks (p = 0.0046) and biopsies (p = 0.0026) compared to non-BRCA mutation carriers. BRCA mutation carriers were also more likely to have cancers diagnosed after biopsies following screening MRI (p = 0.045). 13 BRCA patients were diagnosed with cancer (average age 51). Of the cancers diagnosed after abnormal MRI, 3 were DCIS; all 3 patients had a normal mammogram 4–6 months prior. In those found after abnormal mammogram (n = 6), follow up MRI was performed in 4 cases; all demonstrated the lesion. Three patients were diagnosed younger than 40, 1 on mammogram and 2 on MRI. The patient diagnosed on mammogram had no prior MRI and the lesion was seen on follow-up MRI. Interval screening MRI identified DCIS in BRCA patients with a previous normal mammogram and cancers diagnosed on mammogram were all identified on follow-up MRI. These findings support further evaluation of MRI alone until age 40 in BRCA mutation carriers.

Mechanisms to increase cascade testing in hereditary breast and ovarian cancer: Impact of introducing standardized communication aids into genetic counseling

AIM

Precancer identification of women with hereditary breast and ovarian cancer (HBOC) could prevent 20% of these ovarian cancers. The objective was to determine whether standardized Facing Our Risk of Cancer Empowered (FORCE) materials are acceptable, improve knowledge of HBOC and increase disclosure to family members.

METHODS

A prospective cohort of women with breast or ovarian cancer was identified prior to genetic testing. Subjects completed a baseline knowledge survey and were provided three communication aids. Knowledge, acceptability and communication to family members were reassessed at 6 months and compared to a retrospective cohort who had undergone genetic testing for breast or ovarian cancer prior to the intervention. The primary outcome was increase in HBOC knowledge, requiring 20 pre- and postknowledge scores to detect a 10% difference.

RESULTS

Forty women were enrolled. The median age at cancer diagnosis was 50 years and 55% had a family history of breast or ovarian cancer. Though subjects found the resources acceptable, knowledge scores did not improve after their use. Disclosure rates were of no different between cohorts (83% preintervention vs 77% postintervention, P = 0.26) though there was an increase in deleterious mutation carriers, 0% (0/6) preintervention vs 100% (22/22) postintervention. Rates of subsequent testing in relatives were low in both preintervention and postintervention cohorts (0% vs 4.5%).

CONCLUSION

Inclusion of standardized communication tools is acceptable to patients. Knowledge did not improve after their use. In deleterious mutation carriers, disclosure rates increased postintervention.

Beyond BRCA: Review of Hereditary Syndromes Predisposing to Breast Cancer

The majority of our hereditary breast cancer genes incur not only an increased risk for breast cancer but for other malignancies as well. Knowing whether an individual carries a pathogenic variant in a hereditary breast cancer gene can affect not only screening for the patient but for his or her family members as well. Identifying and appropriately testing individuals via multigene panels allows for risk reduction and early surveillance in at-risk individuals. Radiologists can serve as first-line identifiers of women who are at risk of having an inherited predisposition to breast cancer because they are interacting with all women receiving routine screening mammograms, and collecting family history suggestive of the presence of a mutation. We outline here the 11 genes associated with high breast cancer risk discussed in the National Comprehensive Cancer Network Genetic/Familial High-Risk: Breast and Ovarian (version 3.2019) as having additional breast cancer screening recommendations outside of annual mammography to serve as a guide for breast cancer screening and risk reduction, as well as recommendations for surveillance of nonbreast cancers.

Cases and evidence for panel testing in cancer genetics: Is site-specific testing dead?

Historically in cancer genetic counseling, when a pathogenic variant is found which explains the cancers in the family, at risk family members are offered site-specific testing to identify whether or not they have the previously identified pathogenic variant. Factors such as turnaround times, cost, and insurance coverage all made site-specific testing the most appropriate testing option; however, as turnaround times and costs have substantially dropped and the recognition of double heterozygous families and families with nontraditional presentations has increased, the utility of site-specific testing should be questioned. We present four cases where ordering site-specific testing would have missed a clinically relevant pathogenic variant which raises the question of whether or not site-specific testing should be regularly used in cancer genetic testing.

Cholecystectomy: Safe or Not Safe to Drain?

The aim of this study was to determine whether drains influenced the size of subhepatic collections following cholecystectomy, and if these had any affect on complications.

Eighty-five patients undergoing cholecystectomy had either no drain, a narrow bore suction drain or an open corrugated drain. Subhepatic fluid collections were measured by real time ultrasound on the first and fifth postoperative days, and thereafter if necessary. The volumes of fluid drained were also measured and clinical complications recorded. The subhepatic collections were, on average, the same whether a drain was used or not. Drains produced volumes considerably in excess of any subhepatic collection measured, but they did not appear to warn of biliary leakage. More complications (28%) were seen in the drained group compared with the undrained group (10.5%), and furthermore, the complications did not seem to occur in relation to the larger collections. One patient who had had a corrugated drain correctly placed developed biliary peritonitis.

We suggest that drainage of simple cholecystectomy is unnecessary and, if an open drain is used, potentially dangerous.

Current and future role of genetic screening in gynecologic malignancies

The world of hereditary cancers has seen exponential growth in recent years. While hereditary breast and ovarian cancer and Lynch syndrome account for the majority of mutations encountered by gynecologists, newly identified deleterious genetic mutations continue to be unearthed with their associated risks of malignancies. However, these advances in genetic cancer predispositions then force practitioners and their patients to confront the uncertainties of these less commonly identified mutations and the fact that there is limited evidence to guide them in expected cancer risk and appropriate risk-reduction strategies. Given the speed of information, it is imperative to involve cancer genetics experts when counseling these patients. In addition, coordination of screening and care in conjunction with specialty high-risk clinics, if available, allows for patients to have centralized management for multiple cancer risks under the guidance of physicians with experience counseling these patients. The objective of this review is to present the current literature regarding genetic mutations associated with gynecologic malignancies as well to propose screening and risk-reduction options for these high-risk patients.

Thorascopic sympathectomy performed using laser

INTRODUCTION

Thorascopic sympathectomy is accepted as an effective treatment for palmar hyperhidrosis, facial blushing and to a lesser extent for digital ischaemia and axillary hyperhidrosis.

PATIENTS AND METHODS

Data were collected retrospectively on patients undergoing thorascopic sympathectomy at St Peter's Hospital between 1987 and 2006. Patients were followed up by telephone interview.

RESULTS

A total of 233 thorascopic sympathectomy procedures were performed by a single operator in 123 patients. Ages ranged from 9-71 years and 75 were women. In patients, 105 had a bilateral and 13 a unilateral procedure, 5 patients had a bilateral procedure performed in two stages. In 6 upper limbs, the procedure could not be done. Overall, 110 patients (90%) had the procedure performed for palmar hyperhidrosis, 8 (6%) for facial blushing and in 5 (4%) patients the operation was performed for digital ischaemia with tissue loss. There were no deaths and all patients were discharged on day 1 following the procedure. Complications included bleeding (2), pulmonary oedema (1) and failed procedure (2); however, no incidences of Horner's syndrome occurred. Only 40 of 123 (32.5%) patients gave follow-up information. Of this small group, 33 of 40 (83%) were cured, 4 of 40 (10%) were better, 2 of 40 (5%) were unchanged and 1 patient was worse. Only 22 out of 40 (55%) of these patients were troubled by compensatory sweating, with only 4 of 40 (10%) reporting this as a major problem.

CONCLUSIONS

Thorascopic sympathectomy is safe and can be carried out as a single bilateral procedure in the majority of cases. The laser allows the use of a single port, requires less dissection than surgical or clipping techniques, is more precise than diathermy and may be less likely to cause a Horner's syndrome.

Bovine kidney tissue/biological fluid correlation for penicillin

Penicillin is one of the most commonly misused drugs in steers and dairy cows. In the US, at slaughter the tolerance is 50 ng/g in kidney and other edible tissues. If the tolerance is exceeded, the carcass may not be used for human food. A preslaughter test for penicillin in an easily accessible biological fluid is needed to predict if the concentration of penicillin is below tolerance in the kidney before the bovine is slaughtered. In this study, 12 steers were injected three times with the approved dose (7000 IU) of penicillin at 12-h intervals. Blood and urine samples were collected at intervals after the final dose of penicillin. At each sampling point, one kidney biopsy sample was collected by laparoscopic surgery in the live animal. Another kidney sample was collected at slaughter. Correlations between plasma and kidney concentrations and between urine and kidney concentrations were determined. These correlations predict with 95% confidence that 99% of the animals will have kidney tissue below penicillin tolerance when the plasma concentration of penicillin is below 0.4 ng/mL and/or the urine penicillin concentration is below 140 ng/mL.

Looking for long-term mnemonic effects on serial recall: the legacy of Simonides

We investigated three issues with respect to the long-term serial recall of adults. First, retention interval was manipulated to obtain uncontaminated measures of long-term serial recall. Second, we compared serial recall of concrete and abstract nouns to determine how these materials might interact with various learning strategies over time. Third, control group participants were asked to describe the learning strategies used, allowing a comparison of technical mnemonic techniques with the spontaneously generated strategies of adults. We found that the delayed recall performance of participants who spontaneously used organizational or imagery-based strategies was comparable to that of those instructed in the method of loci and pegword technique. Word concreteness did not interact with any other variable. These results are discussed with regard to their implications for serial learning in educational settings.

Linguistic cues and memory for synthetic and natural speech

Past research has demonstrated that there are cognitive processing costs associated with comprehension of speech generated by text-to-speech synthesizers, relative to comprehension of natural speech. This finding has important performance implications for the many applications that use such systems. The purpose of this study was to ascertain whether certain characteristics of synthetic speech slow on-line, real-time cognitive processing. Whereas past research has focused on the phonemic acoustic structure of synthetic speech, we manipulated prosodic, syntactic, and semantic cues in a task requiring participants to recall sentences spoken either by a human or by one of two speech synthesizers. The findings were interpreted to suggest that inappropriate prosodic modeling in synthetic speech was the major source of a performance differential between natural and synthetic speech. Prosodic cues, along with others, guide the parsing of speech and provide redundancy. When these cues are absent or inaccurate, the additional burden placed on working memory may exceed its capacity, particularly in time-limited, demanding tasks. Actual or potential applications of this research include improvement of text-to-speech output systems in warning systems, feedback devices in aerospace vehicles, educational and training modules, aids for the handicapped, consumer products, and technologies designed to increase the functional independence of older adults.

Functional ability assessment: guidelines for the workplace

Short- and long-term disability certification is required in all Western countries for extended time away from work. The Americans With Disabilities Act mandates that medical providers use rational thought and justifiable criteria when evaluating an employee's "fitness for duty". In order to facilitate employment/disability decisions, physicians must now serve as an advisor to the employer. Both the employer and the physician are legally obligated to carefully justify any recommendations for placement or exclusion from the workplace. We propose a uniform methodology that both physicians and employers could use together to determine the performance capability of an individual with a temporary or permanent impairment or disability in terms of essential job functions as defined under the Americans With Disabilities Act.

Outpatient management of deep vein thrombosis

OBJECTIVE

To assess whether patients with deep vein thrombosis (DVT) could be satisfactorily treated on an outpatient basis with low molecular weight (LMW) heparin and warfarin.

DESIGN

A 22 month prospective study of adults attending St Peter's Hospital accident and emergency department with DVT.

RESULTS

1093 patients were referred and assessed; 160 were venogram positive, of which 159 patients between the ages of 22 and 89 years of age have now been treated with LMW heparin as outpatients. Direct liaison with community nurses has minimised the impact on general practitioner workload.

CONCLUSIONS

1272 bed days were saved during this period (an estimated 320,000 pounds). The outpatient treatment of thromboembolism has been shown to be effective and safe.

'To bead or not to bead?'

In subcuticular wound closure, the use of anchorage beads or knots to maintain opposition of wound edges is a common practice, but can lead to complications. One hundred and one abdominal subcuticular wound closures (44 vertical and 57 transverse) were prospectively studied and assessment of wound swelling was made by measuring the length of exposed suture at both ends of the wound, on successive days postoperatively. Results showed progressive reduction in the exposed suture length. We would suggest that if anchorage beads are used with subcuticular sutures then they should not be pulled tight as postoperative wound swelling will cause the beads to be drawn into the wound often resulting in a troublesome ulcer(s) at the end(s) of the wound.

Alcohol and adolescents

Alcohol use has persisted over time as the number one drug problem among youth in the United States. Many primary care physicians underestimate the seriousness and prevalence of teenage alcohol use. The epidemiology of alcohol use among adolescents is discussed, as are its dangers and society's attitude toward drinking. The effects of alcohol on adolescents are listed. Several types of alcoholism are discussed.

The effect of intravenous ranitidine and metoclopramide on behavior, cognitive function, and affect

Both ranitidine and metoclopramide produce neuropsychiatric side effects. Concomitant use of these drugs preoperatively may produce adverse behavioral and emotional changes. Therefore, in 123 unpremedicated patients undergoing tubal occlusion, behavior, cognitive function, and affect were studied before and after a 2-min intravenous injection of placebo (n = 30), ranitidine 50 mg (n = 32), metoclopramide 10 mg (n = 30), or both ranitidine 50 mg and metoclopramide 10 mg (n = 31). Cognitive function was evaluated by the responses to 11 statements devised to assess attitude toward anesthesia and surgery. Affect was assessed by the word chosen out of 11 word-pairs as best describing the feelings at the time. After ranitidine injection, one patient seemed restless and five seemed drowsy. The changes were associated with subjective feelings of agitation (P < 0.05) and restlessness (P < 0.05). After metoclopramide injection, 6 (20%) developed akathisia, 13 (43.3%) seemed restless, and 8 (26.7%) seemed drowsy. The changes were associated with subjective sensation of jumpiness (P < 0.01) and discomfort (P < 0.05). When both ranitidine and metoclopramide were injected, 10 (32.3%) developed akathisia, 4 (12.4%) seemed restless, and 11 (35.5%) seemed drowsy. The changes were associated with subjective feelings of agitation (P < 0.05), jumpiness (P < 0.05), restlessness (P < 0.01), and upset (P < 0.05). Akathisia, a side effect of metoclopramide, seemed to be more prominent when ranitidine was added.

Is the hot appendix really hot?

The skin temperature in the right and left iliac fossae was recorded in 100 patients who were referred with a provisional diagnosis of acute appendicitis. This was not found to be a reliable aid in diagnosis of acute appendicitis nor an indicator to the need for surgery in patients with right iliac fossa pain.

Women and specialty choice: why not anesthesiology?

The number of women in all medical specialties increased during the 1970s and 1980s. Anesthesiology residency programs experienced unprecedented growth from 1980 to 1986. We reviewed statistics published by the American Medical Association to investigate the relationship between the increase in female residents in all specialties compared to that for individual specialties including anesthesiology, pathology, surgery, pediatrics, obstetrics/gynecology, radiology, internal medicine, and psychiatry. We found an above average rate of growth for female residents in gynecology, pediatrics, and internal medicine; pathology, radiology, psychiatry, surgery, and anesthesiology showed a below average rate of growth. Studies have shown a correlation between gender and choice of specialty. Factors influencing the differences in choice and the decrease in the percentage of women choosing anesthesiology are unknown.

Confirmation of oxytetracycline, tetracycline and chlortetracycline residues in milk by particle beam liquid chromatography/mass spectrometry

A method using particle beam liquid chromatography/mass spectrometry was developed for the confirmation of oxytetracycline, tetracycline and chlortetracycline residues in bovine milk. This method is one of the first to apply particle beam technology to the confirmation of animal drug residues in food products for regulatory purposes. The milk is centrifuged, using molecular weight cut-off filters to remove components of 25,000 daltons and above from the milk. The filtrate is passed through a C-18 sample preparation cartridge which retains the tetracyclines. After the columns are washed with water, the tetracyclines are eluted with 0.1 M oxalic acid in methanol and concentrated. The compounds are separated on a Novapak C-18 column with a methanol-oxalic acid-acetonitrile mobile phase. Negative chemical ionization with selective ion monitoring is used to identify the tetracyclines. The procedure was used to confirm the presence of each tetracycline at 100 ng ml-1 in fortified and incurred milk samples.

Retrograde femoral angioplasty: a new technique

Percutaneous transluminal angioplasty cannot be used for lesions of the superficial femoral artery when the origin of the vessel is occluded. A new technique, retrograde femoral angioplasty, is described in which angioplasty is performed from below via the exposed popliteal artery. In four out of six patients retrograde femoral angioplasty was successfully completed, and three of the four vessels remain patent up to 1 year later. The method provides an alternative to the femoropopliteal bypass graft in some patients.

Small bowel function after aortic surgery

One cause of post-operative morbidity in the elective repair of abdominal aortic aneurysms is the development of a paralytic or 'adynamic' ileus. In a series of 20 consecutive patients undergoing such a procedure, the maintenance of small bowel motility and absorptive capacity in the immediate post-operative period was assessed using barium sulphate and xylose passed down a naso-duodenal tube sited at the time of surgery. This simple study demonstrated that small bowel function was preserved in all cases, and hence that patients could be fed enterally via naso-duodenal tube (in particular using very low residue formulae) rather than using costly parenteral regimens, should an ileus persist.

Light reflection rheography: an effective non-invasive technique for screening patients with suspected deep venous thrombosis

Light reflection rheography is a simple non-invasive technique for assessing venous function in the leg. One hundred and twenty-four patients referred for venography with a clinically suspected deep venous thrombosis were investigated by light reflection rheography to determine the accuracy of the technique in diagnosing acute thrombosis. In half of the patients venography confirmed a deep venous thrombosis. Light reflection rheography had a sensitivity of 92 per cent and a specificity of 84 per cent in detecting acute thrombosis. The technique had a negative predictive value of 92 per cent in selecting those patients with no thrombosis. Light reflection rheography can be performed at the bedside or in the radiography department which makes it a suitable technique for screening patients with suspected deep venous thrombosis.

Stroke volume measurements by electrical bioimpedance and echocardiography in healthy volunteers

To evaluate the validity of three equations for estimation of thoracic electrical field size in a new bioimpedance algorithm, stroke volume (SV) as calculated by these equations was compared with that calculated by Doppler echocardiography in 48 healthy volunteers, both lean and obese. When the volume of electrically participating tissue was estimated from body height (modified Sramek) or body height corrected for body habitus (Sramek-Bernstein), there was considerable variation between bioimpedance and Doppler stroke volumes. When the volume of electrically participating tissue was estimated from the actual measurement of the height of the thorax and the circumference at the base of the thorax, the variation in SV differences decreased substantially (Sramek equation), although still considerable for clinical use, and there was no relationship between SV thus obtained and body habitus. Analysis of calculated stroke indices derived by our Doppler echocardiographic standard, as compared with values in the literature, revealed a systematic underestimation. We conclude that the original Sramek equation systematically underestimates SV by 15% to 20%, and the modified Sramek and Sramek-Bernstein equations systematically underestimates SV by 15% to 20%, and the modified Sramek and Sramek-Bernstein equations systematically overestimate SV in females by about 15%, but provide SV values in males in the predicted range. Further studies on the current assumption that the electrical field size is a truncated cone may improve precision of the bioimpedance method.

Pseudomembranous colitis after abdominal aortic aneurysm repair

We report three patients who developed pseudomembranous colitis following aortic aneurysm resection. Colonic ischaemia can occur after such surgery and ischaemic colonic mucosa is known to be more susceptible to damage by bacteria and their toxins. This colonic ischaemia together with the antibiotic prophylaxis used may render aortic aneurysm patients susceptible to pseudomembranous colitis. It is important to distinguish pseudomembranous from ischaemic colitis in these patients as specific and effective drug therapy can be given to those with the pseudomembranous type.

Self protection in surgery: the use of double gloves

This study assesses the perforation rate of single and double gloves and thus the extent to which double gloving protects the surgeon from diseases transmissible from the patient. We have also investigated whether double gloving offers the patient extra protection by reducing wound sepsis. Two hundred adult hernia repairs were performed, the first 100 single gloved and the second 100 double gloved. Glove perforation rates were not significantly different between single gloves and the outer of the double gloves. Although 46 of 400 outer gloves were perforated there were only 15 inner glove perforations and only eight of these matched the outer perforations. The percentage of operations in which the latex protective barrier was breached was reduced from 31 per cent when the surgeon wore single gloves to 8 per cent with double gloves. Wound sepsis was not increased by glove perforation nor reduced by double gloving. While careful technique remains mandatory we conclude that double gloving offers increased protection to the surgeon operating on high risk infectious cases.

Bile leaks after simple cholecystectomy

Drains after cholecystectomy are used commonly to avoid biliary leaks and subsequent peritonitis. Thirty-five patients who had had cholecystectomy without drainage underwent 99mTc-labelled dimethylphenylcarbamoylmethyliminodiacetic acid (HIDA) and ultrasound scans the morning after surgery. Biliary leaks detected by positive HIDA scans occurred in 11 patients. Subhepatic fluid collections were seen on 20 ultrasound scans. There was no relation between biliary leaks and subhepatic collections. Many of the collections were not seen on the HIDA scan, suggesting that they contained blood and not bile. Many of the patients with bile leaks showed no fluid collection. Clinical complications were few and evenly distributed between those with positive and negative scans. We conclude that bile leaks are not an occasional event but occur after 31 per cent of undrained cholecystectomies and that these bile leaks remain clinically unimportant.

Simultaneous determination of oxytetracycline, tetracycline, and chlortetracycline in milk by liquid chromatography

A simple, rapid procedure is described for the simultaneous quantification of 3 tetracycline drugs in bovine milk. Samples are prepared by dilution with an EDTA/phosphate buffer solution and filtration through a molecular weight cutoff filter. Analytes are concentrated on-column using a reverse-phase gradient elution system of oxalic acid, acetonitrile, and methanol. The limits of quantitation are approximately 15-50 ng/mL and the limits of detection are 10-20 ng/mL, depending on the compound. For oxytetracycline, over the range 50-1200 ng/mL, the average recovery and intralaboratory coefficient of variation were 97% and 4.1%, respectively. Over the same range, these parameters were, respectively, 97% and 5.0% for tetracycline, and 89% and 6.4% for chlortetracycline. The applicability of this procedure is demonstrated by separation and detection of incurred tetracycline residues in milk from treated animals.

Peripheral somatic sensory neuropathy and skin galvanic response in the feet of patients with diabetes

The relationship between abnormality in the peripheral sympathetic nervous system (skin galvanic response) and in the peripheral somatic sensory nerve fibers was studied in the lower extremities of 51 patients with diabetes. Deficits in temperature and pain sensations (the small sensory nerve fibers) were related to abnormal sympathetic nervous function (temperature sensation, p less than 0.001; pain sensation, p less than 0.05). The deficits in temperature sensation, in particular, predicted abnormal sympathetic nervous function reliably and vice versa. There was no relationship between deficits in touch and vibration sensations (the large sensory nerve fibers) and abnormal sympathetic nervous function. There was a relationship between skin galvanic response and RR-variation (p less than 0.01). However, abnormality in RR-variation was not related to the deficits in any of the four sensory modalities.

Surgical glove perforation

In a study to investigate the incidence and significance of surgical glove perforation, bacterial contamination of surgeons' hands and gloves before and after operation was measured and the gloves tested for damage. Perforations were found in 74 of 582 gloves (12.7 per cent) and occurred in 34.5 per cent of operations. Glove perforation did not influence bacterial counts on the surgeons' hands or on the outside of their gloves. A separate clinical study of 100 adult hernia repairs gave no evidence that perforation increased wound sepsis. After standard pre-operative hand preparation, glove perforations are of no clinical significance to the patient, but their high incidence should alert surgeons to the need for protection against pathogens transmissible during surgery, such as hepatitis B and the human immunodeficiency virus. Protection of the surgeon is the main indication for preoperative change of damaged gloves.

Sulfamethazine blood/tissue correlation study in swine

Seventy market-weight hogs (90 to 113 kg) were used in a feeding study to determine the correlation of serum sulfamethazine concentrations with sulfamethazine concentrations in liver and muscle at time of slaughter. Test groups were fed medicated feeds prepared from commercial medicated premixes containing 110 g of sulfamethazine/metric ton for 30 days. Fifteen days before hogs were slaughtered, test groups were given maintenance feeds containing 1.1 to 13.9 g of sulfamethazine/metric ton and were fed these diets until slaughtered. Comparison of data from positive- and negative-control groups indicated that total withdrawal of sulfamethazine in the feed was not necessary for the liver to contain less than the allowed tolerance of 0.1 mg of sulfamethazine/kg of liver at slaughter. Feed concentrations of up to 2 g of sulfamethazine/metric ton could be tolerated in withdrawal feeds before liver sulfamethazine values exceeded 0.1 mg/kg of liver. Serum/tissue sulfamethazine ratios were erratic in hogs given 1.1 to 2.7 g of sulfamethazine/metric ton, but became less variable in hogs given greater than 5.7 g/metric ton. Feed concentrations greater than 8 g of sulfamethazine/metric ton produced values greater than 0.1 mg/kg of muscle and values of about 0.4 mg/kg of liver. When serum sulfamethazine concentrations alone were used as a predictor for tissue sulfamethazine values, 100% of the liver values exceeded 0.10 mg/kg of liver when sulfamethazine in serum was greater than 0.45 mg/L. However, 57.4% of samples having serum concentrations between 0.10 and 0.45 mg/L had associated sulfamethazine values greater than 0.1 mg/kg of liver. All hogs having serum sulfamethazine concentrations less than 0.1 mg/L had sulfamethazine concentrations less than 0.1 mg/kg of liver.

Methotrexate toxicity in a patient receiving trimethoprim-sulfamethoxazole

A 61-year-old patient with rheumatoid arthritis receiving treatment with methotrexate developed bone marrow hypoplasia after treatment with trimethoprim-sulfamethoxazole. The bone marrow recovered after stopping methotrexate.

Gold vs D-penicillamine double blind study and followup

We undertook a controlled random double-blind comparing gold and penicillamine. Of the 50 patients with rheumatoid arthritis entered into the study, 34 completed the protocol. We found no significant differences in the clinical results, laboratory variables, or toxicity. Longterm followup of 55 months revealed that a significant number of patients were no longer on either drug. The notable exceptions were those who were felt to be in remission from either drug, and remained on gold, or penicillamine. No toxicity from penicillamine involving known immunological aberration has thus far been encountered.

Quantitative thin layer chromatographic multi-sulfonamide screening procedure: collaborative study

A thin layer chromatographic procedure suitable for detection of multiple sulfonamides at 0.1 ppm was studied in an interlaboratory collaborative study. Sulfamethazine, sulfadimethoxine, and sulfaquinoxaline were variously analyzed in liver and muscle tissues from swine, turkey, and duck. The average recovery for all drugs across all tissues was 95%. The corresponding repeatability and reproducibility were 7.7% and 10.5%, respectively.

Quantitative thin layer chromatographic multi-sulfonamide screening procedure

In-situ optical scanning of fluorescamine derivatives on thin layer silica gel plates provides a rapid method for the determination of multiple sulfonamides at levels below 0.1 ppm. Sample preparation is minimal. Homogenized liver or muscle is extracted with ethyl acetate and then back-extracted into 0.2M glycine buffer. After pH adjustment, the extract is washed with hexane and extracted with methylene chloride. The organic phase is evaporated to dryness and reconstituted in methanol. Pre-adsorbent layer silica gel plates are used for chromatography. The method has been applied to residues of sulfamethazine, sulfadimethoxine, sulfathiazole, sulfaquinoxaline, and sulfabromomethazine in cattle, swine, turkey, and duck tissues.