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M Conley

Publications and source records attributed to M Conley.

44 records · Page 3Linked to original sources

The laminar organization of the lateral geniculate body and the striate cortex in the tree shrew (Tupaia glis).

The organization of geniculostriate projections in Tupaia was studied using three separate methods, anterograde transport from the lateral geniculate, retrograde transport from the striate cortex, and reconstruction of single geniculostriate axons. The results show that each layer of the lateral geniculate body has a unique pattern of projections to the striate cortex, and each pattern consists of a major and a minor target. The two ipsilateral layers project to thin subtiers of layer IV: the major target of geniculate layer 1 is the top of IVa; the major target of geniculate layer 5 is the base of IVb. The minor target of layer 1 is the major target of layer 5. Two of the contralateral layers can be matched to the ipsilateral layers. Layers 1 and 2 are a matched pair and project to IVa; layers 4 and 5 are a matched pair and project to IVb. Thus, projections of a matched pair overlap. The remaining two contralateral layers, 3 and 6, project chiefly to cortical layer III. Layer 3 projects to layers IIIb and I and seems to be the counterpart of the parvocellular C layers in the cat and the intercalated layers in primates. Layer 6 projects to the base of IIIc in a zone contiguous with IVa. This contiguity raises the issue of whether the base of IIIc might actually be a part of layer IV. If this were the case, the two tiers of layer IV which are separated by a conspicuous cleft might be considered two subdivisions of layer IVb.

Afferent Pathways↗

Culture of Plasmodium falciparum: the role of pH, glucose, and lactate.

Yields of P. falciparum in intraerythrocytic in vitro cultures were maximized when extracellular pH was maintained between 7.2 and 7.45, and extracellular lactate was kept below 12 mM. Host erythrocytes metabolized 4.6 +/- 1.5 microM glucose/10(9) RBC/24 hr and produced 7.9 +/- 1.8 microM lactate/10(9) RBC/24 hr. Asynchronous parasite cultures used 122 +/- 34 microM glucose/10(9) parasitized RBC/24 hr and produced 143 +/- 47 microM lactate/10(9) parasitized RBC/24 hr. Synchronous cultures that were 80 to 100% ring forms after 24 hr in culture exhibited significantly lower glycolysis per 10(9) parasitized RBC than cultures that were 0 to 25% ring forms after 24 hr. The percent of glucose utilization accounted for by lactate production by parasites was significantly less than that of uninfected erythrocytes. These optimum ranges and metabolic rates can be used in the development of parasite culture techniques.

Animals↗

Retinal ganglion cell projections to individual layers of the lateral geniculate body in Galago crassicaudatus.

The genus Galago provides an unique opportunity to study the relation between layers of the lateral geniculate body and classes of retinal ganglion cells. In the present experiments HRP was restricted to individual layers of the lateral geniculate body with the following results: After injections of the magnocellular layers, layers 1 and 2, labeled retinal ganglion cells ranged in size from 8 to 20 micrometers. After injections of the parvocellular layers, layers 3 and 6, labeled retinal ganglion cells ranged in size from 6 to 12 micrometers. After injections involving layers 4 and 5, which layers contain only very small, pale cells, labeled retinal ganglion cells ranged in size from 5 to 14 micrometers. Thus, the very largest ganglion cells were labeled only after injections of magnocellular layers 1 and 2, while small and medium retinal ganglion cells were labeled after HRP injections in every layers of the lateral geniculate body. Because the magnocellular layers actually contain a mixture of large, medium, and small-sized cells, we suggest that retinal ganglion cells of different size-classes project to geniculate relay cells of the corresponding size-class.

Animals↗

Different distribution of large and small retinal ganglion cells in the cat after HRP injections of single layers of the lateral geniculate body and the superior colliculus.

Retinal ganglion cells were labeled with HRP after injecting single layers of GL or single strata within the stratum griseum superficiale (SGS). Only small cells were labeled after injecting small cell C layers and upper SGS. Only large cells were labeled after injecting lower SGS. Small and large cells were labeled after injecting medial interlaminar nucleus (MIN) and layers A and A1.

Animals↗

Optokinetic nystagmus in the domestic pigeon. Effects of foveal lesions.

Using both binocular and monocular viewing conditions, optokinetic nystagmus (OKN) frequency-velocity functions were measured before and after ophthalmic laser-produced retinal lesions. With binocular viewing conditions, the range of effective pattern velocities and the upper velocity threshold increased by 20--30 degrees/sec in subjects with both foveas lesioned, and by 12 degrees/sec in a subject with only a single foveal lesion. Subjects with parafoveal lesions showed no change in postlesion binocular OKN response functions. Prelesion monocular OKN functions were obtained for both temporal-to-nasal (T-N) and nasal-to-temporal (N-T) directions of pattern movement. T-N OKN functions were similar to those obtained with binocular viewing but N-T movement elicited OKN over a much narrower range of stimulus velocites. Lesions of the foveal area appeared to have little effect on N-T OKN functions, although an increase in N-T upper velocity thresholds was obtained from at least one eye in 4 of 5 animals. Thus, lesions of the foveal and parafoveal area do not impair, and may actually facilitate, OKN in the pigeon.

Animals↗

Spectrum of pulmonary sequestration.

Bronchopulmonary sequestration was diagnosed in 17 patients ranging in age from newborn to 64 years. The sequestration was intralobar in 14 patients and extralobar in 3. The spectrum of symptoms could be divided into three patterns: no symptoms (6 patients), respiratory problems (8 patients), and cardiovascular problems (3 patients). Cardiovascular problems usually manifest themselves in the first few weeks or months of life and often have a respiratory component. In older patients the sequestration is first manifested by recurrent pulmonary infections or, if it remains uninfected, an asymptomatic density on chest roentgenogram. The definitive diagnostic study is arteriography. Operative treatment for the intralobar variety consists of segmental resection or, if the inflammatory process is more extensive, lobectomy. An extralobar sequestration may simply be excised.

Adolescent↗