The morphology of Oreopithecus bambolii pollical distal phalanx.

Oreopithecus bambolii is a Late Miocene ape from Italy, first described in the late 19th century. Its interpretation is still highly controversial, especially in reference to its hand proportions and thumb morphology. In this study, the authors provide detailed descriptions of the available Oreopithecus pollical distal phalanx (PDP) specimens, as well as bivariate and multivariate morphometric analyses in comparison with humans, extant apes, selected anthropoid monkeys, and available Miocene PDP specimens.

Middle phalanx skeletal morphology in the hand: can it predict flexor tendon size and attachments?

Specific sites on the palmar diaphysis of the manual middle phalanges provide attachment for the flexor digitorum superficialis (FDS) tendon. It has been assumed in the literature that lateral palmar fossae on these bones reflect locations for these attachments and offer evidence for relative size of the flexor tendon. This assumption has led to predictions about relative FDS muscle force potential from sizes of fossae on fossil hominin middle phalanges.

Neural pattern in the human pollical distal phalanx.

A morphological study of the neural pattern in the human ungual region of the pollical distal phalanx was carried out on eight male cadavers. The dissections showed a palmar neural arrangement consisting of four designated ungual nerves, two proximal and two distal, for each of the ulnar and radial palmar digital nerves at the lateral sides of the thumb. This neural configuration was associated with the compartmentalization of its ungual pulp, the difference between the type of sensory receptors within the ungual pulp, the overlapping of the tactile composition at the thumb tip, seen clinically after laceration of one of the palmar digital nerves, and the sensory supply to the nail bed in the dorsal portion of the thumb.

Pollical oblique ligament in humans and non-human primates.

A morphological study of the oblique ligament in the thumb is presented. The ligament was consistently described in human specimens and compared with dissections of non-human primates from different species. The oblique ligament was found in some, but not all, specimens in each of the following species examined: chimpanzee, orangutan, gibbon, anubis baboon, hamadryas baboon, squirrel monkey, lemur and marmoset.

Comparative morphology of the pollical distal phalanx.

Functional analysis of human pollical distal phalangeal (PDP) morphology is undertaken to establish a basis for the assessment of fossil hominid PDP morphology. Features that contribute to the effectiveness of grips involving the distal thumb and finger pulp areas include: 1) distal thumb interphalangeal joint morphology, facilitating PDP conjunct pronation with flexion; 2) differentiation of a proximal, mobile pulp region from a distal, stable pulp region, providing for firm precision pinch grips and precision handling of objects; and 3) asymmetric attachment of the flexor pollicis longus (FPL) tendon fibers, favoring PDP conjunct pronation. A proportionately larger size of the ulnar vs.

Comparison of binding and removal of remnants of triglyceride-rich lipoproteins of intestinal and hepatic origin by rat liver in vitro.

Chylomicrons were isolated from intestinal lymph and very low-density lipoproteins (VLDL) from the perfusate of isolated perfused livers. In vivo the initial phase of clearance of these particles was very rapid. Chylomicrons appeared to be cleared more quickly than VLDL (t1/2 = 3.

Characterization of chylomicron remnant binding to rat liver membranes.

The binding of chylomicron remnants to rat liver membranes was investigated using radioiodinated lipoproteins. The specific activity of binding increased in parallel with increased enrichment in plasma membrane markers. The yield of receptor activity, however, decreased with enrichment.

3-hydroxy-3-methylglutaryl coenzyme A reductase from rat intestine: subcellular localization and in vitro regulation.

The subcellular localization of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in rat intestine was reinvestigated. Highly enriched fractions of endoplasmic reticulum and mitochondria were prepared from mucosal cells. The highest specific activity of HMG-CoA reductase was located in the endoplasmic reticulum fraction with recovery of 25% of the total activity.

Studies on the mechanisms of the rapid modulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase in intact liver by mevalonolactone and 25-hydroxycholesterol.

A rapid, biphasic inhibition of rat hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase (mevalonate:NADP+ oxidoreductase (CoA-acylating), EC 1.1.1.

Rat liver acyl-coenzyme A:cholesterol acyltransferase: its regulation in vivo and some of its properties in vitro.

To gain insight into the role of the enzyme acyl-coenzyme A:cholesterol acyltransferase (ACAT) in cellular cholesterol homeostasis, its regulation in rat liver was investigated both in vivo and in vitro. In vitro assay conditions were optimized and some properties of the microsomal enzyme in vitro was also studied. Arrhenius plots of microsomal ACAT activity showed discontinuities at about 28-29 degrees C and 16-17 degrees C.

Median nerve entrapment syndrome in the proximal forearm.

Median nerve compression in the proximal forearm is relatively uncommon. This study reviews 71 cases over a 20 year period. Of the 71 in this series, 51 were treated surgically.

A reconsideration of the ischiorectal fossa.

The ischiorectal fossae of one fresh and 47 preserved cadaver specimens were dissected to elucidate its fascial boundaries, neurovascular relationships, spatial orientation, and possible functions. Based upon measurements of approximately half of the dissected specimens, a three-dimensional model of the ischiorectal fossa was developed to clarify visually its fascial relationships and orientation within the perineum. Seven fetal specimens were also dissected for comparative purposes.

A systematic study of the oblique retinacular ligament of the human finger: its structure and function.

A dissection of 14 preserved and two fresh human hands, a total of 64 fingers, all from different individuals, showed the oblique retinacular ligament to vary incompleteness and to be functionally present in only 40 to 50% of the specimens, except for the ulnar side of the ring finger where it was present in over 90%. When present, it was made taut by flexion of the distal phalanx, regardless of the postition of the proximal interphalangeal joint. Excision of the ligament when present or in its absence in these fingers, did not alter the coordinated motion of the interphalangeal joints produced by traction on the extrinsic flexors and the lateral bands.

The pronator quadratus in motions and in stabilization of the radius and ulna at the distal radioulnar joint.

Based upon the findings of dissections of 15 forearms and clinical observations in patients with disturbed architecture of the distal radioulnar joint, the pronator quadratus was found to be composed of two heads. A superficial head originated from the ulna and passed transversely to its insertion into the radius. It averaged 5.

3-Hydroxy-3-methylglutaryl coenzyme A reductase from rat liver. Its purification, properties, and immunochemical studies.

3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase, EC 1.1.1.

The fascia of the distal phalanx.

The anatomy of the distal phalanx of the human finger was studied in preserved and fresh specimens and the fascia was related to associated structures as a mechanism for prehension. Particular attention was directed to the lateral interosseous ligaments of the distal phalanx and their possible function during gripping with the digital pulp.

A study of the flexor digitorum superficialis tendon in flexion and extension at the proximal interphalangeal joint.

Using a physical model to represent the detailed morphology of the flexor digitorum superficial tendon, the functions of the fibrous arrangement of this tendon in the human fingers were studied for flexion and extension of the proximal interphalangeal joint. In extension of the joint, the fibrous pattern acted as a dynamic ligament for the joint. In flexion, the arrangement of fiber bundles of the tendon contributed to tha balanced distribution of forces across the joint's surfaces and for mechanical interplay with the deep long flexor tendon in the region of the joint.

A study of the flexor digitorium superficialis tendon in flexion and extension at the proximal interphalangeal joint.

Using a physical model to represent the detailed morphology of the flexor digitorium superficial tendon, the functions of the fibrous arrangement of this tendon in the human fingers were studied for flexion and extension of the proximal interphalangeal joint. In extension of the joint, the fibrous pattern acted as a dynamic ligament for the joint. In flexion, the arrangement of fiber bundles of the tendon contributed to the balanced distribution of forces across the joint's surfaces and for mechanical interplay with the deep long flexor tendon in the region of the joint.