Functionally distinct regions for spatial processing and sensory motor integration in the planum temporale

There has been much debate recently over the functional role played by the planum temporale (PT) within the context of the dorsal auditory processing stream. Some studies indicate that regions in the PT support spatial hearing and other auditory functions, whereas others demonstrate sensory-motor response properties. This multifunctionality has led to the claim that the PT is performing a common computational pattern matching operation, then routing the signals (spatial, object, sensory-motor) into an appropriate processing stream. An alternative possibility is that the PT is functionally subdivided with separate regions supporting various functions. We assess this possibility using a within subject fMRI block design. DTI data were also collected to examine connectivity. There were four auditory conditions: stationary noise, moving noise, listening to pseudowords, and shadowing pseudowords (covert repetition). Contrasting the shadow and listen conditions should activate regions specific to sensory-motor processes, while contrasting the stationary and moving noise conditions should activate regions involved in spatial hearing. Subjects (N = 16) showed greater activation for shadowing in left posterior PT, area Spt, when the shadow and listen conditions were contrasted. The motion vs. stationary noise contrast revealed greater activation in a more medial and anterior portion of left PT. Seeds from these two contrasts were then used to guide the DTI analysis in an examination of connectivity via streamline tractography, which revealed different patterns of connectivity. Findings support a heterogeneous model of the PT, with functionally distinct regions for sensory-motor integration and processes involved in auditory spatial perception.     

Regional and Voxel‐Wise Comparisons of Blood Flow Measurements Between Dynamic Susceptibility Contrast Magnetic Resonance Imaging (DSC‐MRI) and Arterial Spin Labeling (ASL) in Brain Tumors

The objective of the current study was to evaluate the regional and voxel‐wise correlation between dynamic susceptibility contrast (DSC) and arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) measurement of cerebral blood flow (CBF) in patients with brain tumors. Thirty patients with histologically verified brain tumors were evaluated in the current study. DSC‐MRI was performed by first using a preload dose of gadolinium contrast, then collecting a dynamic image acquisition during a bolus of contrast, followed by posthoc contrast agent leakage correction. Pseudocontinuous ASL was collected using 30 pairs of tag and control acquisition using a 3‐dimensional gradient‐echo spin‐echo (GRASE) acquisition. All images were registered to a high‐resolution anatomical atlas. Average CBF measurements within regions of contrast‐enhancement and T2 hyperintensity were evaluated between the two modalities. Additionally, voxel‐wise correlation between CBF measurements obtained with DSC and ASL were assessed. Results demonstrated a positive linear correlation between DSC and ASL measurements of CBF when regional average values were compared; however, a statistically significant voxel‐wise correlation was only observed in around 30‐40% of patients. These results suggest DSC and ASL may provide regionally similar, but spatially different measurements of CBF.     

Neurologic emergencies: case studies

During the past 2 decades, the world has witnessed a significant improvement in the understanding of the pathogenesis and treatment of neurologic diseases, which presents emergencies. Every day neurologists are consulted for patients who present with neurologic emergencies to the emergency departments. In this article, we present a series of case reports about patients with acute neurologic and psychiatric problems and discuss their management briefly.     

Endoscopic Management of Adnexal Masses

Background:

The laparoscopic management of suspicious adnexal masses and early ovarian malignancies is discussed with the aim of maintaining accepted oncologic treatment principles. Comparative survival data of patients with gynecological malignancies managed by laparoscopy or laparotomy are still very scarce and the survival of cancer patients must not be compromised by new techniques. It is time to closely analyze laparoscopy and determine if it has a positive impact on the diagnosis and treatment of ovarian malignancies. In this paper we will address the following points:

• 1) Which ovarian cysts can be surgically treated by laparoscopy (pelviscopy)?
• 2) Is staging laparoscopy an accepted technique?
• 3) Is laparoscopy, as a second-look procedure, of benefit?
• 4) Is laparoscopic staging, together with histologic tissue sampling, adequate surgical technique in inoperable ovarian cancer with ascites and peritoneal carcinomatosis?
• 5) Does endoscopic biopsy of ovarian cancer stage Ia change the destiny of a patient into ovarian cancer Ic?

Data Base:

The above questions are analyzed based on our experience with the laparoscopic treatment of 1,225 patients with ovarian cysts and 165 ovarian cancer patients stage I to IV treated immediately by laparotomy during the years 1992-1995.

Conclusions:

Ovarian cystic tumors with no signs of malignancy can be dealt with by laparoscopic means with the option of immediate conversion to laparotomy or within one week if an ovarian malignancy is diagnosed. Today sampling laparoscopic lymphadenectomy of both pelvic and para-aortic is feasible and adequate. On a curative level, the number of lymph nodes to be resected has yet to be determined. The adnexa can be extracted from the abdominal cavity with bag extraction without the danger of spillage. The uterus can be removed transvaginally with laparoscopic assisted vaginal hysterectomy (LAVH). We must be cautious to advocate laparoscopy for ovarian cancer. However, it is an excellent tool when used as a staging procedure. A careful preoperative screening of the patient and an exact definition of existing cysts with imaging techniques allows us to frequently apply laparoscopic surgery for ovarian cysts, leaving only readily detectable cancer cases for laparotomy. Many gynecological oncologists employing staging and second-look procedures for ovarian cancer agree that initiating a case with laparoscopy may preclude laparotomy for many patients. Tumor propagation by performing a biopsy in FIGO stage Ia ovarian cancer patients does not occur if the patient receives adequate radical surgical treatment within one week. According to the reports of Sevelda et al. and Dembo et al., the degree of differentiation and the existence of ascites are more relevant to decreasing the five-year survival rate of patients with ovarian cancer stage I than the rupture of capsule or penetration of the tumor.^16,17A dependency on the first two parameters was found in these two large statistical studies.As the question of endoscopic operations for adnexal mass is predominantly put for the sanitation of small ovarian tumors (ovarian tumors with solid particles in the cysts can be put into the section of primary laparotomies) there remains a wide field of indications for the laparoscopic treatment of adnexal mass and ovarian cysts with benign indications. For many young patients with non-malignant ovarian lesions such as endometriosis, benign cysts, benign cystic proliferations and fibromas, a laparotomy can be avoided and these lesions treated by laparoscopy.     

Spontaneous Reversal of P‐Glycoprotein Expression in Multidrug Resistant Cell Lines*

Abstract: Increased expression of P‐glycoprotein encoded by the mdr‐1 gene is a well‐characterised mechanism for resistance to cancer chemotherapeutic drugs in cell lines. However, the P‐glycoprotein expression after removal of the selection pressure has not fully been elucidated. The stability of P‐glycoprotein expression in the presence (+) and absence (?) of vincristine (30 or 150 nM) was studied in multidrug resistant K562 cell lines (VCR30+, VCR150+, VCR30? and VCR150?) for 11 months. The P‐glycoprotein protein and mdr‐1 mRNA levels were determined at regular intervals using flow cytometry and real‐time PCR, respectively. Chemosensitivity to a panel of antineoplastic drugs was measured using an MTT assay. The presence of vincristine (VCR30+ and VCR150+) resulted in high and stable levels of P‐glycoprotein and mdr‐1 mRNA during the whole period compared to wild type. As for the VCR30? and VCR150? subcultures, the expressions of P‐glycoprotein and mdr‐1 mRNA were stable for five months, and then the levels decreased rapidly. Concomitantly, the sensitivity to drugs known as P‐glycoprotein substrates was restored. In conclusion, resistant cells growing in the presence of the inducing drug have a stable P‐glycoprotein expression and resistance level, but removing the inducing drug may result in a sudden and rapid lowering of P‐glycoprotein and mdr‐1 mRNA levels as long as five months after drug withdrawal.     

Incidence,survival, pathology,and genetics of adult Latino Americans with glioblastoma

Latino Americans are a rapidly growing ethnic group in the United States but studies of glioblastoma in this population are limited. We have evaluated characteristics of 21,184 glioblastoma patients from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. This SEER data from 2001 to 2011 draws from 28% of the U.S. population. Latinos have a lower incidence of GBM and present slightly younger than non-Latino Whites. Cubans present at an older age than other Latino sub-populations. Latinos have a higher incidence of giant cell glioblastoma than non-Latino Whites while the incidence of gliosarcoma is similar. Despite lower rates of radiation therapy and greater rates of sub-total resection than non-Latino Whites, Latinos have better 1 and 5 year survival rates. SEER does not record chemotherapy data. Survivals of Latino sub-populations are similar with each other. Age, extent of resection, and the use of radiation therapy are associated with improved survival but none of these variables are sufficient in a multivariate analysis to explain the improved survival of Latinos relative to non-Latino Whites. As molecular data is not available in SEER records, we studied the MGMT and IDH status of 571 patients from a UCLA database. MGMT methylation and IDH1 mutation rates are not statistically significantly different between non-Latino Whites and Latinos. For UCLA patients with available information, chemotherapy and radiation rates are similar for non-Latino White and Latino patients, but the latter have lower rates of gross total resection and present at a younger age.