Vasomotor dysfunction in carpal tunnel syndrome

Little attention has been paid to small-fiber dysfunction in carpal tunnel syndrome (CTS) although its symptoms are common. This study investigates vasomotor dysfunction, which is controlled by small nerve fibers, in patients with CTS compared with control subjects. Vasomotor function was quantified by measuring, with laser Doppler velocimetry, skin vasoconstriction induced by a eutectic mixture of local anesthetic (EMLA) cream over digit tips 3, 4, and 5. Hands with CTS (n = 32) compared with controls (n = 19) demonstrated significantly reduced vasoconstriction in digits 3 and 4, but not digit 5. A blood flow ratio (digit 3/5) of less than 0.73 identified CTS in 69% with 68% specificity. Testing for vasomotor dysfunction in CTS allows for more comprehensive neurophysiological testing, which is heavily biased towards large nerve fibers.     

Magnetic resonance imaging to determine the distribution of a vaginal gel: before,during, and after both simulated and real intercourse

To provide effective contraception and protection against sexually transmitted disease, vaginal gels should maximally cover the cervical os and the vaginal epithelium before, during and after intercourse. To non-invasively monitor the intravaginal distribution of an applied intravaginal gel, we performed high-resolution magnetic resonance imaging (MRI) of the female pelvis before, during and after both real and simulated sexual intercourse. We sought to determine whether simulated intercourse with a plastic phallus could be used as a surrogate for real intercourse for such experiments.

Dilute gadolinium chelate solution was mixed with Gynol-II gel and introduced intravaginally to volunteer female human subjects using a conventional applicator. MRI was performed at 1.5 Tesla with a surface coil. Imaging of the female pelvis was performed: (1) immediately after insertion of the gel; (2) during real intercourse with a male partner (2 subjects) or simulated intercourse with a plastic phallus (4 subjects); and (3) after completion of real or simulated intercourse. Subjects were studied after application of both 3 mL and 5 mL of vaginal gel. Measurements of gel thickness covering the vaginal mucosa were made digitally using electronic calipers.

The bolus of gel is initially located in the upper vaginal canal, superior to the urogenital diaphragm. Both real and simulated intercourse dramatically increases the spread of gel to the lower vagina. The cervix appears to be adequately covered with gel both before and after intercourse. Increasing the volume of the gel increases initial vaginal mucosal coverage but also increases leakage from the introitus. No statistically significant differences in vaginal mucosal coverage were found between patients having undergone real vs. simulated intercourse, or on post-intercourse scans of 3 mL versus 5 mL. MRI is a sensitive, reproducible means of tracking the spread of intravaginal medications.     

Magnetic resonance imaging of prostate cancer

Management of carcinoma of the prostate has traditionally been guided by digital rectal examination, and by laboratory data such as serum prostate-specific antigen (PSA) level and histopathologic tumor grade. The introduction of the endorectal coil has improved the ability of magnetic resonance imaging (MRI) to contribute to staging and treatment planning of prostate cancer, especially in cases of confined or locally invasive disease. Exciting research in the fields of magnetic resonance spectroscopy (MRS) and MR-guided intervention of the prostate may soon expand the role of MRI in the diagnosis and treatment of prostate cancer. This article reviews current MRI techniques, the MRI features of prostate cancer, the role and efficacy of MRI in prostate carcinoma staging, and the current and future uses of MR spectroscopy and MR-guided prostate brachytherapy.     

Ethnicity and treatment response in schizophrenia: a comparison of 3 ethnic groups

BACKGROUND: Numerous cultural and ethnic factors may directly and indirectly influence treatment outcome in schizophrenia. The present study compared the response to antipsychotic treatment in 3 ethnic groups of patients with schizophrenia. METHOD: Fifty black, 63 mixed descent, and 79 white patients with DSM-IV-diagnosed schizophrenia or schizophreniform disorder who were participants in multinational clinical drug trials were assessed by means of the Positive and Negative Syndrome Scale (PANSS). Treatment response was measured by the change in PANSS total scores and the change in positive, negative, and general psychopathology subscale scores from baseline to 6 weeks. Also, the percentage of responders (defined as > or = 40% reduction in PANSS total scores) was calculated for each group. RESULTS: Baseline PANSS scores differed significantly, being higher for black and mixed descent patients. Mixed descent patients showed the greatest mean +/- SD percentage reduction in PANSS total score (29.4 +/- 21.6) followed by black (28.4 +/- 14.7) and white (11.4 +/- 27.6) patients. Analysis of covariance revealed a significant effect of ethnicity on the reduction in PANSS total scores (p < .0001). The numbers of responders were 20 mixed descent (32%), 12 black (24%), and 7 white (9%) patients (p = .002). CONCLUSION: Significant ethnic differences in acute antipsychotic treatment response are demonstrated by this study. Factors such as diet, nutritional status, body mass, and substance use could be important, as well as genetically determined ethnospecific pharmacokinetic and pharmacodynamic differences. Delayed help-seeking may account for the higher baseline scores in the black and mixed descent patients.     

Factors that affect National Resident Matching Program rankings of medical students applying for radiology residency

RATIONALE AND OBJECTIVES: A study was performed to determine which factors most influence the program rank lists of U.S. medical students applying for radiology residency and which sources of information about residency programs these medical students value most highly. MATERIALS AND METHODS: Questionnaires were mailed to the 516 U.S. medical students who applied to the authors' radiology residency program in the 2001 National Resident Matching Program match. Respondents were asked to evaluate 23 factors that may have affected their rank lists, on a five-point Likert scale. For data interpretation, factors were categorized as being either within, somewhat within, or outside the control of the program director. Respondents were also asked to evaluate eight potential sources of information about residency programs. RESULTS: The response rate was 23.3% (120 of 516). The three most important factors affecting rank lists were the perceived happiness of current residents within the program, the geographic location of the program, and the academic reputation of the department. Four of the five factors that scored most highly were judged to be outside the program director's control. The most important sources of information were the interview day and personal interactions with residents currently in the program. Program Web sites were rated more highly than the written materials provided. CONCLUSION: Medical students applying for radiology residency use many sources of information and weigh many factors in making their program rank lists. Many of the most influential factors are outside the direct control of the program director.     

Mammographic parenchymal patterns and self-reported soy intake in Singapore Chinese women.

The study aimed to investigate whether self-reported dietary variables were associated with mammographic parenchymal patterns, which have been shown to predict risk of breast cancer. Among the 3,421 women, ages 45-74 years, common to two independent population-based cohorts, mammographic parenchymal patterns and current dietary habits were assessed for 406 randomly chosen participants. Logistic regression methods were used to compare dietary and other lifestyle profiles between subjects classified as displaying high (cases) and low risk (controls) parenchymal patterns. After adjustment for energy intake and other potential confounders, dietary soy protein intake was inversely related to risk of high-risk parenchymal pattern (odds ratio, 0.41; 95% confidence interval, 0.18-0.94, highest versus lowest quartile of intake). Similarly, the highest versus lowest quartile of dietary soy isoflavone intake was significantly related to low-risk parenchymal patterns (odds ratio, 0.44; 95% confidence interval, 0.20-0.98). The association between high soy intake and a reduced risk of mammographic parenchymal patterns that are associated with high breast cancer risk may have important implications in breast cancer prevention.     

Efficacy of herpes simplex virus thymidine kinase in combination with cytokine gene therapy in an experimental metastatic breast cancer model

Immunotherapy in combination with suicide gene therapy for breast cancer was tested using a metastatic animal model. Subcutaneous injection of the nonimmunogenic breast cancer cell line 4T1 in BALB/C mice gave rise to tumors in 100% of mice with both micrometastases and macrometastases in the lung. We used the herpes simplex virus thymidine kinase (HSV-TK) gene along with the cytokine genes granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-2 (IL-2) to determine their effect on tumor regression and inhibition of lung metastasis. Adenoviral (AV) vectors carrying these transgenes, in separate constructs, were used in this study. Intratumoral administration of AV-TK followed by 10 days of ganciclovir treatment resulted in a delay in tumor growth and, in some cases, in a low to moderate reduction in tumor volume. Inclusion of either GM-CSF or IL-2 gene with HSV-TK resulted in a slightly greater reduction in tumor volume, although these data were not significantly different from those obtained for TK treatment alone. However, when both cytokine genes were combined with TK, a substantial reduction in tumor growth was observed compared with HSV-TK alone (P < .02). Tumor weight data also exhibited superior efficacy of TK/GM-CSF/IL-2 treatment when compared with animals treated with TK gene only (P < .01). More importantly, TK/GM-CSF/IL-2 combination gene therapy induced a significant reduction in lung metastasis compared with any other treatment groups in the 4T1 model (P < .001 between TK GM-CSF/IL-2 versus TK only). Surgical excision of primary tumors after TK/GM-CSF/IL-2 plus ganciclovir treatment resulted in anti-metastatic activity that was similar to that observed for animals in which no surgery was performed. Survival analysis showed a significant difference between animals treated with AV-TK/GM-CSF/IL-2 and animals treated with TK only at 35 days after virus injection (P < .01). Immunophenotypic data suggest infiltration of lymphocytes within the tumor microenvironment in TK- and cytokine gene-treated animals. Thus, the overall data presented here demonstrate that TK gene therapy in combination with GM-CSF and IL-2 gene-mediated immunotherapy strategies have important implications in the treatment of breast cancer.