Unit responses to moving stimuli in area 18 of the cat

In paralyzed cats units were recorded from the peripheral projection on area 18. Of 46 cells, 71% responded to moving visual stimuli. From this sample 91% responded to velocities ranging from 5 to 400 degrees·sec⁻¹. Within this group, two classes of neurons could be distinguished.

The first class had small receptive fields and responded repetitively to a moving grating. They had low spontaneous activity and were located in the superficial cortical layers. Random pattern movement elicited no response.

The second class had large receptive fields and higher spontaneous activity. These neurons, found in the deeper layer of the cortex, responded better to slits than to grating. Responses to random pattern motion reached 50–100% of grating motion responses.

A similar distinction holds for fast movement sensitive neurons of area 17. The identification of both these classes with simple and complex cells is discussed.     

The influence of metoclopramide on the composition of human breast milk.

The breast milk prolactin (PRL) has been claimed to play a role in the control of electrolyte composition of the milk. Since metoclopramide has been shown to increase milk production in humans, we have made an attempt to investigate the production, the PRL and sodium concentrations in milk with (group I) and without (group II) maternal metoclopramide treatment (5 days, 30 mg/day). Both groups consisted of 11 mothers and their full-term newborn infants. The daily milk production was significantly higher in the treated group (276.4 +/- 36.6 vs 150.9 +/- 25.3 ml/day, p less than 0.01). The PRL measured by RIA was similar in the milk samples of the metoclopramide treated and control groups (80.5 +/- 17.7 vs 90.7 +/- 27.3 ng/ml). The sodium concentration in the milk of mothers taking metoclopramide was 22.1 +/- 1.6 mmol/l and 24.3 +/- 3.2 mmol/l in the control group (p = 0.59). On the 5th postnatal day the plasma PRL of the newborns of mothers treated with metoclopramide does not differ from the values of the control babies (29.8 +/- 2.6 vs 30.7 +/- 2.4 ng/ml) indicating that the amount of metoclopramide transferred into the milk has no apparent influence on the hypothalamo-hypophyseal axis of the neonate. In conclusion: the maternal metoclopramide treatment augments the milk production without having any effect on the PRL and sodium concentration of human "mature" milk.     

The ascending median raphe projections are mainly glutamatergic in the mouse forebrain

The median raphe region (MRR) is thought to be serotonergic and plays an important role in the regulation of many cognitive functions. In the hippocampus (HIPP), the MRR exerts a fast excitatory control, partially through glutamatergic transmission, on a subpopulation of GABAergic interneurons that are key regulators of local network activity. However, not all receptors of this connection in the HIPP and in synapses established by MRR in other brain areas are known. Using combined anterograde tracing and immunogold methods, we show that the GluN2A subunit of the NMDA receptor is present in the synapses established by MRR not only in the HIPP, but also in the medial septum (MS) and in the medial prefrontal cortex (mPFC) of the mouse. We estimated similar amounts of NMDA receptors in these synapses established by the MRR and in local adjacent excitatory synapses. Using retrograde tracing and confocal laser scanning microscopy, we found that the majority of the projecting cells of the mouse MRR contain the vesicular glutamate transporter type 3 (vGluT3). Furthermore, using double retrograde tracing, we found that single cells of the MRR can innervate the HIPP and mPFC or the MS and mPFC simultaneously, and these double-projecting cells are also predominantly vGluT3-positive. Our results indicate that the majority of the output of the MRR is glutamatergic and acts through NMDA receptor-containing synapses. This suggests that key forebrain areas receive precisely targeted excitatory input from the MRR, which is able to synchronously modify activity in those regions via individual MRR cells with dual projections.     

The permeability of oral leukoplakia

The significant increase in oral cancer mortality necessitates further research on the mechanisms of tumorigenesis. It was the aim of this study to compare the permeability, lipid composition and histopathological characteristics of oral leukoplakia with non-lesional specimens of the same region in 30 cases as well as 11 specimens originating from healthy control buccal mucosa. The permeability (Kp) of tissue biopsies to tritiated nitrosonornicotine was determined in a continuous through-flow perfusion system, lipids were extracted and identified by thin-layer chromatography, and thickness of epithelium and keratin layer assessed by histopathological methods. Results of the measurements showed that the permeability to the tobacco carcinogen, nitrosonornicotine for leukoplakic tissue was higher than for normal control buccal specimens. Non-lesional areas of buccal mucosa, adjacent to leukoplakias, showed hyperplasia and significantly higher permeability values than both leukoplakic and normal buccal control mucosa. The lipid content of the non-lesional sites was intermediate between the increased values of the leukoplakic lesion and of normal control mucosa. The data strongly suggest that the presence of tobacco in the oral cavity may bring about generalized changes even in regions that do not show leukoplakia.     

Preferential associations between oral clefts and other major congenital anomalies

Objectives: To identify preferential associations between oral clefts (CL = cleft lip only, CLP = cleft lip with cleft palate, CP = cleft palate) and nonoral cleft anomalies, to interpret them on clinical grounds, and, based on the patterns of associated defects, to establish whether CL and CLP are different conditions. Design And Settings: Included were 1416 cleft cases (CL = 131, CLP = 565, CP = 720), among 8304 live- and stillborn infants with multiple congenital anomalies, from 6,559,028 births reported to the International Clearinghouse for Birth Defects Surveillance and Research by 15 registries between 1994 and 2004. Rates of associated anomalies were established, and multinomial logistic regressions applied to identify significant associations. Results: Positive associations with clefts were observed for only a few defects, among which anencephaly, encephaloceles, club feet, and ear anomalies were the most outstanding. Anomalies negatively associated with clefts included congenital heart defects, VATER complex (vertebral defects, imperforate anus, tracheoesophageal fistula, and radial and renal dysplasia), and spina bifida. Conclusion: The strong association between all types of clefts and anencephaly seems to be attributable to cases with disruptions; the association between CP and club feet seems to be attributable to conditions with fetal akinesia. Some negative associations may depend on methodologic factors, while others, such as clefts with VATER components or clefts with spina bifida, may depend on biological factors. The different patterns of defects associated with CL and CLP, indicating different underlying mechanisms, suggest that CL and CLP reflect more than just variable degrees of severity, and that distinct pathways might be involved.     

Impact of parenchymal loss on renal function after laparoscopic partial nephrectomy under warm ischemia

Purpose

To elucidate the impact of renal parenchymal loss and the ischemic reperfusion injury (RI) on the renal function after laparoscopic partial nephrectomy (LPN) under warm ischemia (WI).

Methods

Thirty-five patients with a single polar renal mass ≤4 cm and normal contralateral kidney underwent LPN. Transperitoneal LPN with WI using en bloc hilar occlusion was performed. The total differential renal function (T-DRF) using ^99mTc-dimercaptosuccinic acid was evaluated preoperatively and postoperatively over a period of 1 year. A special region of interest (ROI) was selected on the non-tumorous pole of the involved kidney, and was compared with the same ROI in the contralateral kidney. The latter comparison was defined as partial differential renal function (P-DRF). Any postoperative decline in the P-DRF of the operated kidney was attributed to the RI. Subtraction of the P-DRF decline from the T-DRF decline was attributed to the parenchymal loss caused by the resection of the tumor and suturing of the normal parenchyma.

Results

The mean WI time was 22 min, and the mean weight of resected specimen was 18 g. The mean postoperative eGFR declined to 87 ml/min/1.73 m² from its baseline mean value of 97 ml/min/1.73 m² (p value = 0.075). Mean postoperative T-DRF and P-DRF of the operated kidney declined by 7 and 3 %, respectively.

Conclusions

After LPN of small renal mass, decline in renal function is primarily attributed to parenchymal loss caused by tumor resection and suturing of the normal parenchyma rather than the RI.