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CAPÍTULO II: MARCO TEÓRICO

2.2 FUNDAMENTACIÓN TEÓRICA

2.2.10 Herramientas para la gestión financiera de empresas

This variant is one of the three polymorphic

variants, besides Albumins Mexico and Makiritare, to be

of Amerindian origin.

The dispersion of this variant is from the

Canadian and North American Indians [Naskapi, Montagnais,

Sioux, Athabascan (Navajo, Apache) and Shoshonean (Hopi)]

to Eskimos from Alaska and Labrador. Indians from the

middle and south USA, South Americans nor Africans,

Asians, Oceonics and Caucasians have yet to be found with

this variant. The discovery of this variant in so many

tribes have proven anthropological links, for example,

between the English-speaking, Anglican Naskapis and the

French-speaking, Roman Catholic Montagnais, both of whom

are Algonkian-speaking tribes. One plausible explanation

for its polymorphism is inbreeding through several generations

The genetic distribution of Albumin Naskapi on

Table 1.3 shows the heterozygotic frequency to be 8.48% and

the homozygous frequency as 0.36%.

This variant segretates genetically with Gc-1 140

phenotypes and the site of mutation is located between 8

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residues 330 and 446 . This is on the B-turns of albumin

(Fig. 1.4) of Domain II, in between the high affinity binding

sites of bilirubin (Section 1.5.2.3 ) and on one of 164 secondary binding sites for medium chain fatty acids

It is not known if bindingsof these ligands are impaired.

An identical allomorph is albumin Mersin found

in high frequency amonst the Eti Turks of south eastern

TABLE 1.3 The genetic distribution of albumin Naskapi

Tribe Number AlNa/Na AiA/Na AlA/A

Naskapi (Canada) 203 1 54 148

Montagnais (Canada) 128 2 19 207

Sioux (N. America) 160 0 2 158

Athabashan (USA & Canada) 230 1 11 218

Eskimos (Labrador) 124 0 3 121

Eskimos (Canada & USA) 262 0 4 258

Total 1,107 4 93 1,010

% of Total 100 0.36 8.48 91.23

Adapted from Blumberg .

and 9.7% in Tarsus. This discovery of its similarities to

albumin Naskapi is anthropologically interesting because

it strongly suggests the ancestry of these Indians to be 89 from Mongoloid populations in Central and/or Eastern Asia

181 Albumin Naskapi binds more bromophenol blue

34

and thyroxine more tighly than albumin A. Both albumins

55

bind linolenic acid, linoleic acid and haemoglobin

181

equally well . Only albumin A binds riboflavin and

warfarin55. Reaction of penicillin with heterozygous

Albumin Naskapi produces four bands15.

1.6.2.9.4 Albumin Maku

This widely distributed variant is found in

tribes living in the Southern borders of Venezuela and

Brazil5111. The original sighting was in a captured Maku

woman and her three near relatives living among the

in two other individuals in adjacent north central Brazil

(Makiritare-2) and in the trihybrid population of Northern

Brazil (Belem III)303.

The migration of this variant is faster than

Albumin Naskapi at shorter (5-6 hr.) length of electrophoresis,

but this is reversed at longer (19 hr+) running times30

probably because Albumin Naskapi is able to bind more

charged ions during the longer running time to increase

its relative mobility.

1.6.2.9.5 Albumin Syracuse

This was found in a family of Swiss German descent.

Minimal separation was obtained on electrophoresis at

pH 8.6 but the variant separated well on cellulose acetate

. „ c .242

at pH 5.4

1.6.2.10 Dimeric Albumins

1.6.2.10.1 Warao

This dimer was found on two natives of British

Guyana11 and in five familial members of a Warao tribe living 12

in the Orinoco delta . This tribe is thought to originate

from the Andes and blood group-typing detected Karib or

Arawak Indian phenotypes.

This dimer constitutes 30% of the total albumin

content and can be separated easily into monomers by

heating at 56°C for 30 min. Susceptibility to dimerisation

may characterise this variant.

Its electrophoretic mobility is close to a^-

globulin on cellulose acetate and close to the fast-moving

a2~globulin in starch gel. It can be distinguished from

European dimers in the pH 6.0, but not in the 5.0 and

61

1.6.2.10.2 Albumin Makiritare

This dimer is found amongst the Makiritare and

the Piaroa tribes of Venezuela, and rhe Trio and Wajana

of Surinam. The average gene frequency is 0.014, arising

from a total of 41 affected individuals, out of 1,461 members on o of the four tribes: Makiritare, Warao, Trio and Wajana .

This hereditary dominant variant is also thought to be

alike Albumin Warao found in the Warao of Venezuela and 297

Wapishana of Guyana

1.6.2.10.3 Albumin Yanomama

This variant originates from the Yanomamo

Indians living in South Venezuela and Northern Brazil. They

separate on electrophoresis at pH 5.0 and 6.9 showing a 298

slight separation of monomers from dimers

1.6.2.10.4 Albumin dimers in Sweden, USA and Wales

Five carriers were found amongst some orthopaedic

patients in a Swedish clinic although a connection between

this hereditary anomoly with orthopaedics is unproven.

A large number of affected individuals were found in nine

of the 24 relatives of a proband, including a brother who

was homozygous.

The albumin dimer found in a healthy American

Negro carrier and 6 members of his family of nine1^7

could be dissociated into monomers after reduction and

.v . .. 136 alkylation

The electrophoretic mobility of the Welsh

dimer, which was the first reported case of hereditary 91

dimers is similar to a dimer found in the USA, except

that they differed in binding of alkaline haematin and

b

2

11 spanning three generations.

1.6.3 Non-hereditary transient bisalbuminemia

1.6.3.1 Introduction

Transient bisalbuminemia is a rarer phenomenon than

hereditary bisalbuminemia with about 50 reported cases from

1948 to 1979. It can be easily recognised as it appears in

lesser quantities than normal albumin during acute illness

as a fast (anodic) band adjacent to the normal allotype.

It usually disappears before complete recovery from illness

is secured. The fast band can be induced by ligand binding

or by pancreatic diseases.

Unlike hereditary bisalbuminemia, the drug- and

enzyme-induced forms are not usually clear distinct bands

. . . . 215

m vivo or in vitro, except within certain limits . Both albumins are usually immunochemically similar and

investigation of familial albumin excludes the hereditary

factor.

The initial reports of transient persistant

double albumins were by Glatthaar11*5 , Sandor22^,

42 > 274

Brodenstein and Rau and is reviewed by Tarnoky and

Porta215.

1.6.3.2 By Pancreatic Diseases

A fast albumin component was observed in a

47 year old woman with subacute pancreatitis with

hyperamylasemia. The concentration of the fast component

was later recognised to be directly proportional to the

serum amylase level. It constituted less than 50% of

the total serum albumin, even when the serum amylase 245

63

However, with the report of a aase of bisalbu-

minemia associated with chronic pancreatitis which was

indifferent to the level of amylase was reported, Lamotte- 155

Barillon suggested structural modification of albumin A

by trypsin.

Pancreatic enzymes were later shown to cause

formation of a more anodic component by limited proteolysis

of albumin A in a clinical case of pancreatitis with

hyperamylasemia. The same effect could be reproduced

in vitro by the limited action of chymotrypsin with carboxypeptidase A and B and elastasis-carboxypeptidase

A and B on albumin A. Trypsin acts merely to activate

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