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J W Patterson

Publications and source records attributed to J W Patterson.

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

Cutaneous phaeohyphomycosis due to Cladophialophora bantiana.

We present a case of cutaneous infection due to Cladophialophora bantiana, an agent of phaeohyphomycosis. The patient developed a nodule with pustule formation on the dorsum of the left hand; no trauma was reported. The lesion was successfully treated with itraconazole and surgical excision. Histopathologically, there was a blastomycosis-like tissue reaction pattern. Pigmented organisms were readily identified in tissue sections, and the cultural characteristics were those of Cladophialophora bantiana. This organism, known primarily for intracerebral involvement, can rarely produce cutaneous and subcutaneous infection. Immunosuppression should be suspected but is not always clinically apparent, as was demonstrated by our case.

Aged↗
PubMed1999

Extraparotid Warthin's tumor.

Warthin's tumor (papillary cystadenoma lymphomatosum) is a well-known benign tumor of the parotid gland. Extraparotid tumors occasionally arise in the cervical region, where they may well be seen by the dermatologist. The following is a case report of an extraparotid Warthin's tumor encountered in a dermatology practice, with a review of the important clinical and histopathologic features of this tumor.

Adenolymphoma↗
PubMed1999

Rapid oral hydration results in hydronephrosis as demonstrated by bedside ultrasound.

STUDY OBJECTIVE: To determine whether vigorous oral hydration (20 mL/kg) causes hydronephrosis as determined by bedside ultrasound. METHODS: We conducted a prospective laboratory trial in 35 healthy volunteers weighing less than 90 kg and between the ages of 18 and 50 years. The right kidney of the volunteers was scanned by emergency physicians at time 0 both before and after voiding, and the volunteers then drank 20 mL/kg of bottled water. The kidney was scanned in the transverse and sagittal planes both before and after voiding at 60 and 90 minutes after completion of the water load. The scans were interpreted by a physician trained and credentialed in emergency ultrasound, blinded to the volunteers' identity, the time of the scan, and the volume of urine voided by the subject. Images were rated as to the degree of hydronephrosis according to literature-established criteria, as follows: grade 0=no hydronephrosis, grade 1=mild, grade 2=moderate, and grade 3=severe hydronephrosis. RESULTS: Hydronephrosis was present in 3 (8.6%) of the 35 subjects at time 0 (prehydration), 24 (68.6%) at 60 minutes, and 20 (57.1%) at 90 minutes. Overall, hydronephrosis occurred at least once in 28 (80%) of the 35 subjects after oral hydration compared with 3 (8.6%) of the 35 subjects before hydration. Hydronephrosis was found to be significantly related to forced hydration for all posthydration times (60 minutes, 90 minutes, and 60+90 minutes combined) versus prehydration time 0 (P <.001). CONCLUSION: Without prior fluid intake, even mild degrees of hydronephrosis were relatively uncommon, and seen in only 8.6% of study patients. In the presence of vigorous oral hydration, however, mild or moderate hydronephrosis is a frequent occurrence seen at least once in 80% of our study of healthy volunteers after hydration. Caution is warranted in this setting when interpreting mild or moderate hydronephrosis found on bedside ultrasound by emergency physicians.

Adolescent↗
PubMed1999

A comparison of melanin bleaching and azure blue counterstaining in the immunohistochemical diagnosis of malignant melanoma.

Distinguishing heavily pigmented melanocytes from melanophages on routine hematoxylin and eosin slides can be difficult. Melanin bleaching with potassium permanganate solution is a traditional means of removing melanin from tissues and can be used before immunohistochemical staining to remove any pigment that might be confused with the brown chromogen diaminobenzidine. Azure B stains melanin granules green-blue, easily contrasts with diaminobenzidine, and may be used as a counterstain on unbleached sections after immunohistochemical staining. To our knowledge, studies comparing melanin bleaching with azure B counterstaining in the immunohistochemical evaluation of malignant melanomas have not been performed. Paraffin sections from 33 heavily pigmented malignant melanomas were bleached with a 3.0-g/L potassium permanganate solution, immunohistochemically stained for S-100 and HMB-45, and counterstained with hematoxylin. Unbleached sections were similarly stained for S-100 and HMB-45 and counterstained with azure B. To establish optimal permanganate concentrations, a variable number of sections were bleached with lower permanganate concentrations ranging from 0.125 to 2.5 g/L. S-100 antigenicity was preserved at all permanganate concentrations, whereas HMB-45 antigenicity was abolished at concentrations of 0.5 g/L and greater. At permanganate concentrations from 0.125 to 0.5 g/L, both antigenicities were preserved; however, melanin was incompletely removed. Complications of bleaching included tissue damage and loss of cytologic detail. Positive immunohistochemical staining was observed in azure B counterstained sections. Azure B stained melanin greenblue and was easily distinguished from the brown diaminobenzidine chromogen, regardless of the antibody tested. Neither tissue damage nor loss of cytologic detail was observed. We conclude that the use of azure B counterstaining is superior to permanganate bleaching in the histologic evaluation of heavily pigmented cutaneous malignant melanomas.

Antigens, Neoplasm↗
PubMed1998

Familial multiple blue nevi.

The blue nevus most commonly presents as a solitary blue nodule. Four histologic variants of blue nevus have been described. Rarely, multiple blue nevi blue nevi may occur in a single person. Only 1 case of familial multiple blue nevi has been described.

Adolescent↗
PubMed1998

Pilomatricoma: an alarming presentation.

Pilomatricoma is an uncommon, benign growth with origination from the hair matrix that may have several clinical presentations and is frequently misdiagnosed. This case of a rapidly growing pilomatricoma in a 26-year-old was particularly deceptive, generating a differential diagnosis, principally of malignant tumors. The typical features, variants, histogenesis, differential diagnosis, and therapy are reviewed.

Adult↗
PubMed1997

Nonpigmented dysplastic melanocytic nevi.

BACKGROUND: Dysplastic melanocytic nevi (DMN) are thought to represent a clinical and histologic bridge between common pigmented nevi and superficial spreading malignant melanoma. The following clinical criteria for DMN were established to aid in the proper identification of these lesions: irregular perimeter, size exceeding 5 mm in diameter, background erythema, and variegated color (shades of browns, tans, blacks, and reds). Histologic features include basilar melanocytic proliferation with nuclear atypia, a patchy lymphocytic infiltrate with concentric eosinophilic fibroplasia, and lamellar fibroplasia. To our knowledge, there have been no previously reported cases of uniformly nonpigmented DMN. OBSERVATIONS: A 31-year-old brown-haired, browneyed white woman with no personal or family history of either DMN or melanoma presented for evaluation of numerous, discrete, nonindurated, 2- to 5-mm-diameter, nonpigmented macules and slightly elevated papules that had appeared in a truncal distribution over the course of several years. Microscopic examination of these lesions showed lentiginous epidermal hyperplasia and disordered proliferation with variable cellular atypia of intraepidermal melanocytes. CONCLUSIONS: Nonpigmented, nonindurated, macular or slightly elevated papular lesions may represent nevi with features of dysplasia. In light of the significant risk of malignant melanoma that is associated with pigmented varieties of dysplastic nevi, it is essential that clinicians consider nonpigmented DMN in the differential diagnosis of entities that present as hypopigmented macules.

Adult↗
PubMed1996

Structure-activity relationships for inhibition of inosine monophosphate dehydrogenase by nuclear variants of mycophenolic acid.

Structure-activity relationships in the region of the phthalide ring of the inosine monophosphate dehydrogenase inhibitor mycophenolic acid have been explored. Replacement of the lactone ring with other cyclic moieties resulted in loss of potency, especially for larger groups. Replacement of the ring by acyclic substituents also indicated a strong sensitivity to steric bulk. A phenolic hydroxyl group, with an adjacent hydrogen bond acceptor, was found to be essential for high potency. The aromatic methyl group was essential for activity; the methoxyl group could be replaced by ethyl to give a compound with 2-4 times the potency of mycophenolic acid in vitro and in vivo.

Animals↗
PubMed1996

Ultrastructural changes in skeletal muscle mitochondria in gram-negative sepsis.

Energy metabolism during sepsis is incompletely understood, but alterations in mitochondrial structure and function appear important. We measured time-dependent changes in mitochondrial structure during sepsis using serial skeletal muscle biopsies in anesthetized baboons injected with 10(10) CFU/kg of live Escherichia coli (LD(100)). Skeletal muscle biopsies were taken before bacterial challenge (0 h controls) and at 12 h, 24 h, and death. By qualitative electron microscopy, the organelles became enlarged with distorted cristae and developed electron lucent areas within the matrix. With advanced injury the inner membrane became fragmented. Quantitative morphometric analysis showed a 50% increase in mean cristal membrane surface density by 24 h (p < .05) accompanied by a 100% increase in intermembrane space (p < .01). Matrix volume density decreased progressively (p < .01). These changes in mitochondrial ultrastructure occur within 12 h after the onset of the bacterial insult. This damage, including destruction or reorganization of both membrane and matrix proteins, is severe enough to compromise oxidative metabolism in muscle in Gram-negative sepsis.

Animals↗
PubMed1995

Effect of CBC results on ED management of women with lower abdominal pain.

Recent studies have suggested that the results of complete blood counts (CBCs) are neither sensitive nor specific in diagnosing abdominal pain, but no study has attempted to determine whether CBC results actually influence the management of ED patients. This study attempted to determine whether CBC results in women with lower abdominal pain affect ED disposition or diagnosis. One hundred women between the ages of 15 and 45 with lower abdominal pain presenting to a community hospital ED with an annual census of 45,000 were enrolled in this prospective study. Before review of the CBC results but after review of all other studies, the ED physician recorded a presumptive diagnosis and indicated whether consultation and/or admission were warranted. After the results of the CBC were reviewed, these factors were reassessed. Patient management or ED diagnosis was affected in two cases (2%; 95% confidence interval 0% to 7%), one resulting in appropriate discharge and one resulting in unnecessary admission. It was concluded that in young women with abdominal pain CBC results rarely affect clinical decision-making.

Abdominal Pain↗
PubMed1995

Comparison of transthecal digital block and traditional digital block for anesthesia of the finger.

STUDY OBJECTIVE: To compare the newly described transthecal (TT) and traditional (TD) methods of digital block anesthesia with regard to length of time to achieve anesthesia and pain during infiltration. DESIGN: Prospective, randomized, controlled, blinded study. PARTICIPANTS: Healthy adult paid volunteers. INTERVENTIONS: Each subject received a TT block on one hand and a TD block on the opposite hand. All blocks were performed by the same investigator and were rated by an evaluator who was blinded to the technique that was used. Time to loss of pin-prick sensation was measured, and the pain of the procedure was recorded by the subject on a 10-cm visual-analog scale. RESULTS: A total of 162 blocks (81 TT and 81 TD) were performed in 31 different subjects. All blocks were successful. Mean time to anesthesia for TT block was 188 seconds compared with 152 seconds for the TD block (P < .01). Mean analog pain score was slightly higher for TT block than for TD block (1.7 versus 1.4, P = .02). CONCLUSION: TT block is clinically equal to the TD method in terms of time to anesthesia and visual-analog pain score.

Adolescent↗
PubMed1994

Effects of hydrogen peroxide oxidation and calcium channel blockers on the equatorial potassium current of the frog lens.

Hydrogen peroxide, in concentrations of 10-1000 microM, produces two major changes in the current-voltage relationships associated with the equatorial potassium current of the lens. First, the resting and reversal potentials become more negative than they were prior to treatment with hydrogen peroxide and second, the membrane resistance related to the equatorial current is decreased. The shift in the resting and reversal potentials is in the opposite direction from that produced by ouabain. Based on the Nernst equation, the shift in the reversal potential suggests that there is an increase in the concentration of potassium in the lens. The 86Rb uptake and efflux are increased. These observations suggest that hydrogen peroxide stimulates the Na,K-pump. The decrease in membrane resistance is inhibited by 100 microM of quinine, a calcium-dependent potassium channel blocker, and does not decrease in a calcium-free medium. This suggests that the decrease in resistance may be secondary to an increase in lenticular calcium. These effects of hydrogen peroxide are similar to those of p-chloromercuriphenylsulfonate (pCMPS), a nearly impermeant sulfhydryl binding agent, and suggest that permeant hydrogen peroxide may increase calcium influx by acting on sulfhydryl groups on the outer surface of lens membranes. Verapamil, a calcium channel blocker, is reported to prevent cataract formation. D600, the methoxy analogue of verapamil, is a calcium channel blocker that increases the resistance associated with the equatorial current in the presence and absence of hydrogen peroxide. The gadolinium ion has a similar effect. Thus, D600 and Gd3+ partially counteract the reduction in membrane resistance produced by 50 microM hydrogen peroxide.

Animals↗
PubMed1994

Cutaneous malacoplakia.

Indurated, erythematous plaques of the left arm and left flank developed in a 69-year-old white man with multiorgan failure from Escherichia coli sepsis. Cutaneous malacoplakia was diagnosed. Intravenous antibiotic therapy resulted in resolution of the malacoplakia and the E. coli sepsis.

Aged↗
PubMed1994

Evaluation of an interactive computer video tutorial on malignant melanoma.

We evaluated medical student reaction to a computer-assisted interactive tutorial on malignant melanoma, a pigmented skin cancer. The tutorial was programmed for use with IBM Infowindow Touchscreen systems which integrate full-color video images from laser videodisc with text and graphics from a personal computer. Second-year medical students at the Medical College of Virginia responded to a questionnaire and rated both the content and the process of learning with this method more highly than presentation of similar content from textbooks.

Attitude↗