Identification of a parathyroid hormone in the fish Fugu rubripes.

A PTH gene has been isolated from the fish Fugu rubripes. The encoded protein of 80 amino acid has the lowest homology with any of the PTH family members. Fugu PTH(1-34) had 5-fold lower potency than human PTH(1-34) in a mammalian cell system. INTRODUCTION: Parathyroid hormone (PTH) is the major hypercalcemic hormone in higher vertebrates. Fish lack parathyroid glands, but there have numerous attempts to identify and isolate PTH from fish. MATERIALS AND METHODS: Polymerase chain reaction (PCR) was performed with primers based on preliminary data from the Joint Genome Institute database. PCR amplification was performed on genomic DNA isolated from Fugu rubripes. PCR products were purified and DNA was sequenced. All sequence was confirmed from more than one independently amplified PCR product. Multiple sequence alignments were carried out, and the percentage of identities and similarities were calculated. An unrooted phylogenetic tree, using all the known PTH and PTH-related protein (PTHrP) amino acid sequences, was determined. Synthetic peptides were tested in a biological assay that measured cyclic adenosine 3',5'-monophosphate formation in UMR106.1 cells. Rabbit polyclonal antisera specific for N-terminal human PTHrP and one rabbit polyclonal antiserum specific for N terminus hPTH were used to test the cross-reactivity with fPTH(1-34) in immunoblots.     

Ultrastructural changes in the rat kidney following fetal exposure to ethanol.

Previous studies have implicated renal ultrastructural abnormalities in the pathogenesis of tubular dysfunction in fetal alcohol syndrome. Scanning electron microscopic studies were performed to examine the role of glomerular and tubular structural changes in this syndrome. Pregnant Sprague-Dawley rats were fed a liquid diet in which ethanol constituted 35% of the total caloric content or pair-fed an isocaloric control diet from gestational day 8 to the day of birth. After delivery, offspring were housed with the dam and left undisturbed until 18 days of age when they were weaned and given free access to standard chow diet and water. At random, kidneys from 11 offspring of ethanol-fed (E) rats and 7 pair-fed control (C) rats were fixed by in vivo retrograde perfusion at 90 days of age for ultrastructural studies. The E rats showed cytoplasmic mitochondrial atrophy and vacuolar structures of the epithelial cells of the distal tubules and collecting ducts not seen in C rats. No obvious difference was found in the glomerular, proximal tubule, or loop of Henle architecture between the two groups. These findings suggest that rats prenatally exposed to ethanol have renal ultrastructural abnormalities that may be important in the genesis of functional disturbances.     

Phase reversal of biomechanical functions and muscle activity in backward pedaling

Computer simulations of pedaling have shown that a wide range of pedaling tasks can be performed if each limb has the capability of executing six biomechanical functions, which are arranged into three pairs of alternating antagonistic functions. An Ext/Flex pair accelerates the limb into extension or flexion, a Plant/Dorsi pair accelerates the foot into plantarflexion or dorsiflexion, and an Ant/Post pair accelerates the foot anteriorly or posteriorly relative to the pelvis. Because each biomechanical function (i.e., Ext, Flex, Plant, Dorsi, Ant, or Post) contributes to crank propulsion during a specific region in the cycle, phasing of a muscle is hypothesized to be a consequence of its ability to contribute to one or more of the biomechanical functions. Analysis of electromyogram (EMG) patterns has shown that this biomechanical framework assists in the interpretation of muscle activity in healthy and hemiparetic subjects during forward pedaling. Simulations show that backward pedaling can be produced with a phase shift of 180 degrees in the Ant/Post pair. No phase shifts in the Ext/Flex and Plant/Dorsi pairs are then necessary. To further test whether this simple yet biomechanically viable strategy may be used by the nervous system, EMGs from 7 muscles in 16 subjects were measured during backward as well as forward pedaling. As predicted, phasing in vastus medialis (VM), tibialis anterior (TA), medial gastrocnemius (MG), and soleus (SL) were unaffected by pedaling direction, with VM and SL contributing to Ext, MG to Plant, and TA to Dorsi. In contrast, phasing in biceps femoris (BF) and semimembranosus (SM) were affected by pedaling direction, as predicted, compatible with their contribution to the directionally sensitive Post function. Phasing of rectus femoris (RF) was also affected by pedaling direction; however, its ability to contribute to the directionally sensitive Ant function may only be expressed in forward pedaling. RF also contributed significantly to the directionally insensitive Ext function in both forward and backward pedaling. Other muscles also appear to have contributed to more than one function, which was especially evident in backward pedaling (i.e. , BF, SM, MG, and TA to Flex). We conclude that the phasing of only the Ant and Post biomechanical functions are directionally sensitive. Further, we suggest that task-dependent modulation of the expression of the functions in the motor output provides this biomechanics-based neural control scheme with the capability to execute a variety of lower limb tasks, including walking.     

The catalytic rate constant. Effect of acetone on acidic hydrolysis of ester cyclohexyl acidacetylomethyl (AmMC)

The catalytic rate constants k(HCl) were established for hydrolysis of beta-lactam moiety in AmMC using equation k(obs) = k(H2O) + k(HCl)[HCl]. The estimate the effect of aceton the relation log k(HCl) = log kD + k Z(mu)/D was applied. The rate constant increases with the decrease of dielectric constant of the solvent.     

Kinetics and mechanism of degradation of some 2-sulfanilamidopyrimidine derivatives. Part 2. Log k--pH profile for sulfadimidine autoxidation.

The overall first order rate constants for the reaction of degradation of sulfadimidine (kobs. = kOX+kh) in the presence of the air oxygen were determined from the measurements of absorbance in 0-1 M HCl at 243 nm, using "the feathering technique". The apparent first order rate constants for autoxidation of sulfadimidine at 403, 411 and 418 K, in the pH range 2-0--9-2 were calculated from the equation kOX = kobs. -- kh, where kh are the rate constants for hydrolysis carried out under nitrogen. The rate of sulfadimidine autoxidation is a function of concentration of the undissociated form (kOX = kOX-fHA). The thermodynamic parameters of the reaction: Ha, deltaHNo., deltaSNo. and logA were determined for the specific rate constant of autoxdiation (kOX).     

Anxiety and depression and their influence on the quality of life after total hip replacement: preliminary report

Objective. The study investigated health-related quality of life in relation to mental status (anxiety and depression) and demographic factors in patients before and after total hip replacement due to osteoarthrosis. Methods. The SF-36, HADS, socio-demographic data questionnaire was delivered to a group of 184 subjects (108 females, 76 males) at the mean age at the time of surgery of 59 years. Questionnaires were delivered to the subjects 2 weeks before the surgery and 6 months after the operation (by mail). Results. Patients after hip replacement showed significant improvement in health-related quality of life in most domains of SF-36 score and summary scale of PCS (Physical Component Summary Scale) and MCS (Mental Component Summary Scale). They also showed improvement in mental status. Elderly patients were more likely to show worse score in MCS and PCS before and after surgery. BMI (body mass index) was correlated only with preoperative PCS. Mental status was associated with postoperative PCS and MCS. Patients who were satisfied with the results of the surgery showed higher PCS and MCS score. Conclusion. Hip replacement surgery brings significant improvement to the quality of life. Age and mental status of those patients influence markedly their postoperative performance.     

Tissue-resident T cells lose their SIP_1 exit visas

CD8 T cells play critical roles in controlling intracellular pathogensand tumors. To accomplish this the small number of antigen-inexperienced naive CD8 T cells that are capable of recognizing the antigen of interest must first become primed. These initial activaion events occur while the responding T cells are sequestered within lymph nodes, but many of the cells subsequently egress into the periphery and migrate into other organs where they can fulfill their principle mission of identifying and eliminating infected or malignant target cells.